Comparison of perioperative outcomes and complications between intracorporeal, extracorporeal, and hybrid ileal conduit urinary diversion during robot-assisted radical cystectomy: a comparative propensity score-matched analysis from nationwide multi-institutional study in Japan.

BACKGROUND: To investigate the impact of different urinary diversion (UD) techniques on the peri- and postoperative complications of robot-assisted radical cystectomy (RARC) with ileal conduit. METHODS: We retrospectively analyzed 373 patients undergoing RARC with ileal conduit at 11 institutions in Japan between April 2018 and December 2021. Propensity score weighting was performed to adjust for confounding factors such as age, sex, body mass index, performance status, American Society of Anesthesiologists score, previous abdominal surgery, neoadjuvant chemotherapy, and preoperative high T stage (≥ cT3) and high N stage (≥ cN1). Perioperative complications were then compared among three groups: extracorporeal, intracorporeal, and hybrid urinary diversion (ECUD, ICUD, and HUD, respectively). RESULTS: A total of 150, 68, and 155 patients received ECUD, HUD, and ICUD, respectively. Bowel reconstruction time and UD time were significantly shorter in the ECUD group (p < 0.001), and console time was significantly longer and blood loss was significantly higher in the ICUD group (p < 0.001). For postoperative complications (Clavien-Dindo Classification grade ≥ 3), surgical site infection (p = 0.004), pelvic abscess (p = 0.013), anastomotic urine leak (p = 0.007), and pelvic organ prolapse (p = 0.011) significantly occurred in the ECUD group. For all grades, ileus was more common in the HUD group, whereas anastomotic stricture was more common in the ECUD group compared with the other groups (p < 0.05). CONCLUSIONS: Severe complications did not increase after HUD and ICUD compared with ECUD; however, console time tended to be longer and blood loss was slightly higher during RARC.

Evaluation of the Characteristics of Ovarian Endometriomas in Patients with Endometriosis: Efficacy of a Low-Dose Estrogen/Progestogen Combination.

OBJECTIVES: Approximately 17-44% of women diagnosed with endometriosis have ovarian endometriomas (cysts). Although ovarian endometriomas may adversely affect quality of life and work performance, the associations among patient characteristics, cyst size, and pain in women with endometriosis have not yet been reported. Thus, the objective of this study was to assess the association among age, cyst size, and pain in women with ovarian endometriomas. DESIGN: This was a retrospective secondary analysis of pooled data from six randomized clinical trials on the use of low-dose estrogen/progestogen drugs for endometriosis. PARTICIPANTS/MATERIALS, SETTING, AND METHODS: Data on 491 patients enrolled in four randomized and two nonrandomized trials between 2003 and 2017 were pooled. None of the participants had undergone surgical treatment before trial participation. We examined differences in dysmenorrhea score, menstrual pain score, analgesic score, and pelvic pain, as measured using a visual analog scale (VAS), by age and endometrioma size. RESULTS: The mean dysmenorrhea, menstrual pain, and analgesic scores were 4.2, 2.2, and 2.0, respectively. The mean VAS for pelvic pain was 55, which decreased significantly with an increase in age. Age was not associated with endometrioma size, including volume and maximum diameter, or dysmenorrhea score. Additionally, endometrioma volume and maximum diameter were not associated with menstrual pain, analgesic score, or pelvic pain. LIMITATIONS: The details of past treatment history were not available; therefore, these could not be considered in the analysis. Additionally, the assessment of pain is heavily influenced by psychological factors, making it difficult to assess the true extent of pain. CONCLUSIONS: Endometrioma size was not associated with dysmenorrhea or pelvic pain measured using the VAS.

Prognostic factors for employment outcomes in patients with a history of childhood-onset drug-resistant epilepsy.

Objective: The employment outcomes of childhood-onset drug-resistant epilepsy (DRE) has not been studied enough. The aim of this retrospective cohort study is to investigate the employment outcomes of childhood-onset DRE in June 2022 and identify the risk factors associated with non-employment. Materials and methods: The sample consisted of 65 participants ≥18 years of age with a history of childhood-onset DRE. Fifty participants (77%) were salaried employees and 15 participants (23%) were non-employed. Clinical and psychosocial information were evaluated for calculating the relative risk (RR) of non-employment. Results: Regarding medical factors, lower IQ [RR, 0.645; 95% confidence interval (CI), 0.443-0.938; p = 0.022] was positively associated with employment. In contrast, age at follow-up (RR, 1.046; 95% CI, 1.009-1.085; p = 0.014); number of ASMs at follow-up (RR, 1.517; 95% CI, 1.081-2.129; p = 0.016); use of medications such as phenobarbital (RR, 3.111; 95% CI, 1.383-6.997; p = 0.006), levetiracetam (RR, 2.471; 95% CI, 1.056-5.782; p = 0.037), and topiramate (RR, 3.576; 95% CI, 1.644-7.780; p = 0.001) were negatively associated with employment. Regarding psychosocial factor, initial workplace at employment support facilities (RR, 0.241; 95% CI, 0.113-0.513; p < 0.001) was positively associated with employment. In contrast, complication of psychiatric disorder symptoms (RR, 6.833; 95% CI, 2.141-21.810; p = 0.001) was negatively associated with employment. Regarding educational factor, graduating schools of special needs education (RR, 0.148; 95% CI, 0.061-0.360; p < 0.001) was positively associated with employment. Conclusions: Specific medical, psychosocial, and educational factors may influence the employment outcomes of childhood-onset DRE. Paying attention to ASMs' side effects, adequately preventing the complications of psychiatric disorder symptoms, and providing an environment suitable for each patient condition would promote a fine working status for people with childhood-onset DRE.

Identifying risk factors for adverse events of pyridoxal phosphate in infantile epileptic spasms syndrome.

INTRODUCTION: Infantile epileptic spasms syndrome (IESS) is characterized by epileptic spasms, regardless of hypsarrhythmia on electroencephalogram or neurodevelopmental delay. In Japan, pyridoxal 5'-phosphate (PLP) is often used as the first-line treatment for IESS because it is effective in a certain number of patients. Although several studies have reported serious adverse events following PLP treatment, no study has investigated the risk factors for such occurrences. OBJECTIVE: To investigate adverse events associated with PLP therapy for the treatment of IESS and to identify the associated risk factors. MATERIALS AND METHODS: We retrospectively evaluated adverse events in 59 patients with IESS at Tottori University Hospital between January 1995 and September 2022. We subsequently collected and analyzed their clinical data and analyzed the risk factors associated with each adverse event. The cutoff values and relative risk (RR) were analyzed for items with significant associations with adverse events. RESULTS: Twenty-seven (51.9%) participants experienced adverse events, including vomiting in 16 participants (59.3%), elevated liver enzyme levels in 15 participants (55.6%), and rhabdomyolysis in two participants (3.4%). No significant differences were observed between the non-adverse events group and the overall adverse events group, as well as between the non-adverse events group and the vomiting group, in terms of the factors examined. However, when comparing the non-adverse events group with the group with elevated liver enzyme levels, age at PLP treatment showed a negative correlation, whereas PLP dose showed a positive correlation with elevated liver enzyme levels. The cutoff dose was 40 mg/kg/day (73.3% sensitivity and 60.7% specificity), and the cutoff age was 9 months (100% sensitivity and 40.0% specificity). RRs of doses ≥40 mg/kg/day and age <9 months were 2.6 and 3.6, respectively. CONCLUSIONS: Adverse events of PLP therapy, including vomiting, elevated liver enzymes, and rhabdomyolysis, were observed in approximately half of the participants. Age under 9 months and a dose ≥40 mg/kg/day were identified as risk factors for elevation of liver enzymes on PLP treatment in infants with IESS, with rhabdomyolysis can occur in the younger or higher dose cases.

Prediction model for long-term seizure and developmental outcomes among children with infantile epileptic spasms syndrome.

Introduction: Children with infantile epileptic spasms syndrome (IESS) are likely to experience poor outcomes. Researchers have investigated the factors related to its long-term prognosis; however, none of them developed a predictive model. Objective: This study aimed to clarify the factors that influence the long-term prognosis of seizures and their development and to create a prediction model for IESS. Materials and methods: We conducted a retrospective cohort study enrolling participants diagnosed with IESS at the Tottori University Hospital. We examined the seizure and developmental status at 3 and 7 years after the IESS onset and divided the participants into favorable and poor outcome groups. Subsequently, we analyzed the factors associated with the poor outcome group and developed a prediction model at 3 years by setting cutoff values using the receiver operating characteristic curve. Results: Data were obtained from 44 patients with IESS (19 female patients and 25 male patients). Three years after epileptic spasms (ES) onset, seizure and development were the poor outcomes in 15 (34.9%) and 27 (61.4%) patients, respectively. The persistence of ES or tonic seizures (TS) after 90 days of onset, moderate or severe magnetic resonance imaging abnormalities, and developmental delay before IESS onset were significantly associated with poor outcomes. Seven years after the onset of ES, seizures and development were the poor outcomes in 9 (45.0%) and 13 (72.2%) patients, respectively. We found that no factor was significantly associated with poor seizure outcomes, and only developmental delay before IESS onset was significantly associated with poor developmental outcomes. Our prediction model demonstrated 86.7% sensitivity and 64.3% specificity for predicting poor seizure outcomes and 88.9% sensitivity and 100% specificity for predicting poor developmental outcomes. Conclusion: Our prediction model may be useful for predicting the long-term prognosis of seizures and their development after 3 years. Understanding the long-term prognosis during the initial treatment may facilitate the selection of appropriate treatment.

Efficacy of indocyanine green systemic administration for bile leak detection after hepatectomy: a protocol for a prospective single-arm clinical trial with a historical control group.

INTRODUCTION: Bile leakage (BL) after hepatectomy cannot always be detected with conventional methods; moreover, BL cannot be completely prevented. Recently, navigation procedures with indocyanine green (ICG) have been reported. Furthermore, we previously reported the possibility of detecting BLs with high sensitivity during hepatectomy by administering ICG into the bloodstream, which is quickly excreted in the bile. This study aims to verify whether detecting and addressing ICG leakage from the hepatic dissection plane using an ICG camera can reduce the bilirubin concentration in the drainage fluid, and consequently, the incidence of BL. METHODS AND ANALYSIS: This prospective single-centre non-randomised single-arm trial will be conducted with historical controls. Overall, 85 patients will be enrolled, including 40 and 45 in the ICG and historical control groups, respectively. In the ICG group, 10 mg/2 mL of ICG will be transvenously or transportally administered during liver surgery. After its uptake by liver cells and excretion into bile, it will be visualised using a camera following the completion of hepatectomy, and the site of ICG leakage will be sutured. Moreover, we will record the number of bile leak spots detected by the naked eye and ICG camera. The primary endpoint of the study will be the total bilirubin concentration in the drain fluid on postoperative day 3, and we will determine whether the concentration differs significantly between the ICG and historical control groups. The results of our study will be used to suggest whether intraoperative ICG administration and evaluation at the hepatic dissection plane can be widely used in liver surgery for more reliable detection of BL and consequent reduction of biliary fistula. ETHICS AND DISSEMINATION: The protocol was approved by the Certified Review Board of Tottori University Hospital (approval number: 21C002). Findings from this trial will be published in peer-reviewed journals and presented at academic conferences. TRIAL REGISTRATION NUMBER: jRCTs061210043.

Molecular and functional characterization of an evolutionarily conserved CREB-binding protein in the Lymnaea CNS.

In eukaryotes, CREB-binding protein (CBP), a coactivator of CREB, functions both as a platform for recruiting other components of the transcriptional machinery and as a histone acetyltransferase (HAT) that alters chromatin structure. We previously showed that the transcriptional activity of cAMP-responsive element binding protein (CREB) plays a crucial role in neuronal plasticity in the pond snail Lymnaea stagnalis. However, there is no information on the molecular structure and HAT activity of CBP in the Lymnaea central nervous system (CNS), hindering an investigation of its postulated role in long-term memory (LTM). Here, we characterize the Lymnaea CBP (LymCBP) gene and identify a conserved domain of LymCBP as a functional HAT. Like CBPs of other species, LymCBP possesses functional domains, such as the KIX domain, which is essential for interaction with CREB and was shown to regulate LTM. In-situ hybridization showed that the staining patterns of LymCBP mRNA in CNS are very similar to those of Lymnaea CREB1. A particularly strong LymCBP mRNA signal was observed in the cerebral giant cell (CGC), an identified extrinsic modulatory interneuron of the feeding circuit, the key to both appetitive and aversive LTM for taste. Biochemical experiments using the recombinant protein of the LymCBP HAT domain showed that its enzymatic activity was blocked by classical HAT inhibitors. Preincubation of the CNS with such inhibitors blocked cAMP-induced synaptic facilitation between the CGC and an identified follower motoneuron of the feeding system. Taken together, our findings suggest a role for the HAT activity of LymCBP in synaptic plasticity in the feeding circuitry.

Efficacy of Tokishakuyakusan add-on therapy with low-dose oral contraceptive pills on endometriosis patients with dysmenorrhea.

AIM: Tokishakuyakusan (TSS) is representative of popular Kampo medicines for Japanese women to treat dysmenorrhea, irregular menstruation and menopause. Current hormonal treatments and low-dose oral contraceptives (OCs) used as a first-choice drug for primary symptoms, however, have a high incidence of adverse events without improving patients' satisfaction. We evaluated the efficacy of TSS as additional treatment on the quality of life (QOL) of patients taking OCs with reduced therapeutic satisfaction. METHODS: Twelve patients treated with OCs for endometriosis were enrolled. TSS (7.5 g/day) in combination with OCs were given for three menstrual cycles. The main outcome was the degree of QOL assessed using the Endometriosis Health Profile-30 (EHP-30). Secondary outcomes were the Menstrual Distress Questionnaire (MDQ), patient's satisfaction using a Likert scale and cold feeling-visual analogue scale (VAS). RESULTS: In EHP-30, significant changes by TSS with OCs in each menstrual cycle were not found, although the scores for pain and emotional well-being tended to decrease. In MDQ, water retention in the premenstrual phase was improved. With regard to cold feeling-VAS, 61.6 mm at pretreatment decreased to 31.3 mm at the endpoint. Average Likert scale values after TSS treatment declined from 4.3 to 2.6. Cold feeling and patient's satisfaction have improved. CONCLUSION: Although the influence of TSS add-on therapy on QOL was moderate, possible improvement of cold feeling and menstruation-related symptoms was suggested.

Peri-operative efficacy and long-term survival benefit of robotic-assisted radical cystectomy in septuagenarian patients compared with younger patients: a nationwide multi-institutional study in Japan.

BACKGROUND: To determine the peri-operative safety and oncological value of robotic-assisted radical cystectomy (RARC) for older and younger patients in an initial Japanese RARC series. METHODS: We retrospectively analyzed the demographics, complications, peri-operative and oncological outcomes of 253 consecutive patients with bladder cancer who underwent RARC at 34 institutions in Japan between April 2009 and March 2017. The patients were assigned to groups according to ages at surgery of < 70 (younger; n = 125) and ≥ 70 (older; n = 128) years. RESULTS: Mean Charlson comorbidity index (p = 0.045) and the incidence of a history of previous abdominal surgery (p = 0.002) were significantly higher, whereas a history of neoadjuvant chemotherapy (p = 0.028) and neobladder (p < 0.001) were significantly lower in the older group. Mean total operative time was significantly shorter (p = 0.019) and mean estimated blood loss (p = 0.013) was significantly lower in the older group. Post-operative Grade ≥ II complications were comparable at 0-30, 31-90 and 91 days after surgery despite urinary tract associations. Rates of positive surgical margins and mean numbers of removed lymph nodes were comparable between the two groups. Although 5-year overall survival rates were significantly lower (p = 0.03) for older patients, 5-year cancer-specific (p = 0.10) and recurrence-free survival rates were comparable (p = 0.20) between the groups. CONCLUSION: Using RARC potentially allows the application of less invasive procedures and cancer control for septuagenarian patients that are equivalent to those for younger patients.

The efficacy and safety of dydrogesterone for treatment of dysmenorrhea: An open-label multicenter clinical study.

AIMS: Dydrogesterone is a retro-progesterone preparation widely used for over a half century. We sought to evaluate the efficacy and safety of dydrogesterone in Japanese women with dysmenorrhea. METHODS: This study was conducted as an open-label, single-arm, multicenter study. One dydrogesterone 5-mg tablet (Duphaston) was administered orally twice daily for 21 days from the 5th to 25th day of each menstrual cycle. A total of 44 (safety analysis) and 31 patients (efficacy analysis) were enrolled. Total dysmenorrhea score, dysmenorrhea subscale scores, dysmenorrhea visual analog scale, severity of menstruation-related lower abdominal pain, low back pain, headache, and nausea/vomiting, basal body temperature, and serum estradiol and progesterone levels were evaluated. RESULTS: Baseline of the total dysmenorrhea score was 4.61, which went down over time following the administration of dydrogesterone, and the decrease was statistically significant at and after 2nd cycle of menstruation. Mean change from baseline at the final evaluation point was -1.84 (P < 0.001). Severity of menstruation-related lower abdominal pain, low back pain, headache, and nausea/vomiting, in the evaluated menstruation cycles tended to decrease over time. Basal body temperature showed a biphasic pattern in 70% at baseline, 50% in 2nd menstruation cycle, and 61% in 5th menstruation cycle, and at least half of the patients may have had ovulation during the treatment. Incidence of adverse drug reactions was 31.8%, and the most common adverse event was metrorrhagia. CONCLUSION: Dydrogesterone is efficacious, safe, and clinically beneficial in patients with dysmenorrhea, thereby indicating that dydrogesterone can be considered as a treatment option for patients with dysmenorrhea.

Pharmacological effects of cannabinoids on learning and memory in Lymnaea.

Cannabinoids are hypothesized to play an important role in modulating learning and memory formation. Here, we identified mRNAs expressed in Lymnaeastagnalis central nervous system that encode two G-protein-coupled receptors (Lymnaea CBr-like 1 and 2) that structurally resemble mammalian cannabinoid receptors (CBrs). We found that injection of a mammalian CBr agonist WIN 55,212-2 (WIN 55) into the snail before operant conditioning obstructed learning and memory formation. This effect of WIN 55 injection persisted for at least 4 days following its injection. A similar obstruction of learning and memory occurred when a severe traumatic stimulus was delivered to L. stagnalis In contrast, injection of a mammalian CBr antagonist AM 251 enhanced long-term memory formation in snails and reduced the duration of the effects of the severe traumatic stressor on learning and memory. Neither WIN 55 nor AM 251 altered normal homeostatic aerial respiratory behaviour elicited in hypoxic conditions. Our results suggest that putative cannabinoid receptors mediate stressful stimuli that alter learning and memory formation in Lymnaea This is also the first demonstration that putative CBrs are present in Lymnaea and play a key role in learning and memory formation.

Two Strains of Lymnaea stagnalis and the Progeny from Their Mating Display Differential Memory-Forming Ability on Associative Learning Tasks.

The pond snail Lymnaea stagnalis learns and forms long-term memory (LTM) following both operant conditioning of aerial respiratory behavior and classical conditioning of taste aversive behavior. In the present study, we examined whether there are interstrain differences in the ability to form LTM following these two types of conditioning. A strain of Lymnaea (TC1) collected in Alberta, Canada exhibits superior memory-forming ability following aerial respiratory operant conditioning compared to a laboratory-reared strain of Lymnaea from Netherlands known as the Dutch strain. We asked whether the offspring of the Canadian TC1 and Dutch snails (i.e., filial 1 (F1) cross snails) would have the superior memory ability and found, rather, that their memory ability was average like the Dutch snails. That is, the Canadian TC1 snails have superior ability for LTM formation following aerial respiratory operant conditioning, but the Dutch and the generated F1 cross have average ability for memory forming. We next examined the Canadian TC1, Dutch and F1 cross snails for their ability to learn and form memory following conditioned taste aversion (CTA). All three populations showed similar associative CTA responses. However, both LTM formation and the ratio of good-to-poor performers in the memory retention test were much better in the Dutch snails than the Canadian TC1 and F1 cross snails. The memory abilities of the Canadian TC1 and F1 cross snails were average. Our present findings, therefore, suggest that snails of different strains have different memory abilities, and the F1 cross snails do not inherit the memory ability from the smart strain. To our knowledge, there have been a limited number of studies examining differences in memory ability among invertebrate strains, with the exception of studies using mutant flies.

Strain-specific differences of the effects of stress on memory in Lymnaea.

Stress alters the ability to form, recall and maintain memory according to the Yerkes-Dodson/Hebb (YDH) law. The effects of environmentally relevant stressors, such as low environmental calcium and crowding, on learning and memory have previously been described in a laboratory-reared 'average' strain of Lymnaea stagnalis (i.e. the Dutch strain) as well as two strains of freshly collected L. stagnalis with enhanced memory formation abilities (i.e. 'smart' snails). Here, we use L. stagnalis to study the effects of other environmentally relevant stressors on memory formation in two other strains of freshly collected snails, one 'smart' and one 'average'. The stressors we examined are thermal, resource restriction combined with food odour, predator detection and, for the first time, tissue injury (shell damage). We show that the same stressor has significantly different effects on memory formation depending on whether snails are 'smart' or 'average'. Specifically, our data suggest that a stressor or a combination of stressors act to enhance memory in 'average' snails but obstruct memory formation in 'smart' snails. These results are consistent with the YDH law and our hypothesis that 'smart' snails are more easily stressed than 'average' snails.

Cerebral Giant Cells are Necessary for the Formation and Recall of Memory of Conditioned Taste Aversion in Lymnaea.

The pond snail Lymnaea stagnalis can acquire conditioned taste aversion (CTA) as a long-term memory. CTA is caused by the temporal pairing of a stimulus, such as sucrose (the conditioned stimulus; CS), with another stimulus, such as electric shock (the unconditioned stimulus; US). Previous studies have demonstrated changes in both cellular and molecular properties in a pair of neurons known as the cerebral giant cells (CGCs), suggesting that these neurons play a key role in CTA. Here we examined the necessity of the pair of CGC somata for the learning, memory formation and memory recall of CTA by using the soma ablation technique. There was no difference in the feeding response elicited by the CS before and after ablation of the CGC somata. Ablation of the CGC somata before taste-aversion training resulted in the learning acquisition, but the memory formation was not observed 24 h later. We next asked whether memory was present when the CGC somata were ablated 24 h after taste-aversion training. The memory was present before performing the somata ablation. However, when we tested snails five days after somata ablation, the memory recall was not present. Together the data show that: 1) the somata of the CGCs are not necessary for learning acquisition; 2) the somata are necessary for memory formation; and 3) the somata are necessary for memory recall. That is, these results demonstrate that the CGCs function in the long-term memory of CTA in Lymnaea.

SR-16234, a Novel Selective Estrogen Receptor Modulator for Pain Symptoms with Endometriosis: An Open-label Clinical Trial.

Background: SR-16234 is a selective estrogen receptor modulator (SERM) structurally different from approved SERM and has been reported to have estrogen receptor (ER) α antagonistic activity and strong affinity with a weak partial agonistic activity to ERß receptor. SR-16234 showed strong inhibitory effects on transplanted endometrial cysts in the endometriosis model of rat and mouse. In this clinical trial, efficacy and safety of SR-16234 have been evaluated in endometriosis patients. Methods: This trial was an open-label single arm clinical trial. Ten patients with dysmenorrhea and pelvic pain associated with endometriosis and adenomyosis were enrolled in this trial, and received 40 mg of SR-16234 once daily for 12 weeks. The primary endpoint was the visual analogue scale (VAS) of pelvic pain. The secondary endpoints included dysmenorrhea score, pelvic pain score, objective observations (stiffness of Douglas' pouch, limitation of uterine movement, size of ovarian chocolate cysts, thickness of endometrium, and serum CA125 concentration) and safety. Results: After oral administration of SR-16234 40 mg for 12 weeks, there were statistically significant decreases in pelvic pain VAS, total pelvic pain score, total dysmenorrhea score, stiffness of Douglas' pouch, limitation of uterine movement compared with the baseline values. Conclusion: The present trial suggested that a selective estrogen receptor modulator could be used for treatment of pain associated with endometriosis for the first time.

Qualitatively different memory states in Lymnaea as shown by differential responses to propranolol.

Mixed results with the synthetic ß-adrenergic receptor blocker, propranolol, have been reported in human populations with regards to its therapeutic efficacy for PTSD treatments targeting the memory reconsolidation process. Stress alters the ability to form and maintain memory, but whether the causal neuronal mechanisms underling memory formation in PTSD are similar to normal memory is not clear. Here, we use Lymnaea to study the effects of combinations of stressors on the quality of the formed memory state. We show reactivation dependent pharmacologic disruption of reconsolidation using propranolol in Lymnaea; specifically, we show that only certain memories created under conditions of a combination of stressors are susceptible to disruption. Our data suggest that phenotypically similar memories may be molecularly diverse, depending on the conditions under which they are formed. Applied to human PTSD, this could account for the mixed results in the literature on disrupting reconsolidation with propranolol.

Heat stress enhances LTM formation in Lymnaea: role of HSPs and DNA methylation.

Environmentally relevant stressors alter the memory-forming process in Lymnaea following operant conditioning of aerial respiration. One such stressor is heat. Previously, we found that following a 1 h heat shock, long-term memory (LTM) formation was enhanced. We also had shown that the heat stressor activates at least two heat shock proteins (HSPs): HSP40 and HSP70. Here, we tested two hypotheses: (1) the production of HSPs is necessary for enhanced LTM formation; and (2) blocking DNA methylation prevents the heat stressor-induced enhancement of LTM formation. We show here that the enhancing effect of the heat stressor on LTM formation occurs even if snails experienced the stressor 3 days previously. We further show that a flavonoid, quercetin, which inhibits HSP activation, blocks the enhancing effect of the heat stressor on LTM formation. Finally, we show that injection of a DNA methylation blocker, 5-AZA, before snails experience the heat stressor prevents enhancement of memory formation.

Training Lymnaea in the presence of a predator scent results in a long-lasting ability to form enhanced long-term memory.

Lymnaea exposed to crayfish effluent (CE) gain an enhanced ability to form long-term memory (LTM). We test the hypothesis that a single CE exposure and operant conditioning training leads to long lasting changes in the capability of snails to form LTM when tested in pond water four weeks later. We trained both juvenile and adult snails with a single 0.5 h training session in CE and show that LTM was present 24 h later. Snails trained in a similar manner in just pond water show no LTM. We then asked if such training in CE conferred enhanced memory forming capabilities on these snails four weeks later. That is, would LTM be formed in these snails four weeks later following a single 0.5 h training session in pond water? We found that both adult and juvenile snails previously trained in CE one month previously had enhanced LTM formation abilities. The injection of a DNA methylation blocker, 5-AZA, prior to training in adult snails blocked enhanced LTM formation four weeks later. Finally, this enhanced LTM forming ability was not passed on to the next generation of snails.

An automated learning apparatus for classical conditioning of Lymnaea stagnalis.

BACKGROUND: The pond snail Lymnaea stagnalis is capable of taste avoidance classical conditioning (TAC) with sucrose as the conditional stimulus (CS) and mechanical prodding as the unconditional stimulus (US). After successful training, feeding behavior is significantly suppressed in response to CS presentation. NEW METHOD: An automated apparatus is described for the training of multiple snails up to 10 snails at the same time. The new apparatus employs an electrical shock obtained from a 9-V dry cell to deliver a consistent and effective current amplitude of 0.4µA (i.e., the US). RESULTS: Using this apparatus, 10 snails can be conditioned simultaneously. We found that the optimal parameters to result in both short (STM) and long-term memory (LTM) were 15 paired presentations of the CS and US with a 5-min inter-trial interval (ITI) and 0.2-s current duration. However, both STM and LTM were observed with other ITIs tested. Successful TAC with only a single pairing of the CS-US occurred with a CS of 100mM sucrose solution for 60s followed by a US of 9V with 0.4µA for 5s. COMPARISON WITH EXISTING METHOD: The use of automated training apparatus for TAC will enable us to better examine the relationship between strength of CS and US.