Comparing the Efficacy of Fosnetupitant, an NK1 Receptor Antagonist in CDDP-Based Regimens, with That of Fosaprepitant and Aprepitant: A Retrospective Observational Study.

Existing antiemetic therapy against emetic-risk agents across malignancies 24 h post-dose in the acute period in cisplatin (CDDP)-based regimens yields a satisfactory complete response (CR) rate of ≥90%. However, the control rate after 24 h in the delayed period is unsatisfactory. This study compared the efficacy of fosnetupitant (F-NTP), a neurokinin 1 receptor antagonist, with that of fosaprepitant (F-APR) and aprepitant (APR) in the treatment of patients with cancer at high emetic risk due to chemotherapy. In this retrospective case-control study involving patients receiving cisplatin-containing regimens and neurokinin 1 receptor antagonists, patients were divided into three groups based on prophylactic antiemetic therapy: F-NTP, F-APR, and APR. The CR rate was evaluated for each period up to 168 h and further subdivided into acute (0-24 h), delayed (24-120 h), overall (0-120 h), and beyond-delayed (120-168 h) periods. Eighty-eight patients were included in the F-NTP group, 66 in the F-APR group, and 268 in the APR group. The CR rates at 0-168 and 120-168 h after cisplatin administration were significantly higher in the F-NTP group than in the F-APR and APR groups. After adjusting for confounding factors, F-NTP use was an independent factor in the multivariate analysis. Prophylactic antiemetic therapy, including F-NTP, was effective and well-tolerated during the delayed period. The efficacy of F-NTP in managing chemotherapy-induced nausea and vomiting was superior to those of F-APR and APR during the study period.

A Comparative Study of the Antiemetic Effects of α2-Adrenergic Receptor Agonists Clonidine and Dexmedetomidine against Diverse Emetogens in the Least Shrew (Cryptotis parva) Model of Emesis.

In contrast to cats and dogs, here we report that the α2-adrenergic receptor antagonist yohimbine is emetic and corresponding agonists clonidine and dexmedetomidine behave as antiemetics in the least shrew model of vomiting. Yohimbine (0, 0.5, 0.75, 1, 1.5, 2, and 3 mg/kg, i.p.) caused vomiting in shrews in a bell-shaped and dose-dependent manner, with a maximum frequency (0.85 ± 0.22) at 1 mg/kg, which was accompanied by a key central contribution as indicated by increased expression of c-fos, serotonin and substance P release in the shrew brainstem emetic nuclei. Our comparative study in shrews demonstrates that clonidine (0, 0.1, 1, 5, and 10 mg/kg, i.p.) and dexmedetomidine (0, 0.01, 0.05, and 0.1 mg/kg, i.p.) not only suppress yohimbine (1 mg/kg, i.p.)-evoked vomiting in a dose-dependent manner, but also display broad-spectrum antiemetic effects against diverse well-known emetogens, including 2-Methyl-5-HT, GR73632, McN-A-343, quinpirole, FPL64176, SR141716A, thapsigargin, rolipram, and ZD7288. The antiemetic inhibitory ID50 values of dexmedetomidine against the evoked emetogens are much lower than those of clonidine. At its antiemetic doses, clonidine decreased shrews' locomotor activity parameters (distance moved and rearing), whereas dexmedetomidine did not do so. The results suggest that dexmedetomidine represents a better candidate for antiemetic potential with advantages over clonidine.

Torsade de pointes secondary to long QT syndrome after intragastric balloon placement. A rare but severe complication.

The obesity pandemic is becoming one of the most prevalent diseases nowadays. There is a wide spectrum of treatment, ranging from hygienic-dietary measures to bariatric surgery. Endoscopic intragastric balloon placement is becoming increasingly more frequent, due to its technical simplicity, safety and short-term success(1). Although complications are rare some can be severe, so pre-endoscopic evaluation must be carried out carefully. A 43-year-old woman with a history of grade I obesity (BMI 32.7) had an Orbera® intragastric balloon implanted successfully. After the procedure she presented frequent nausea and vomiting, partially controlled with antiemetics. She attended the Emergency Department(ED) with a persistent emetic syndrome - oral intolerance and short-term loss of consciousness(syncope), for which she was admitted. Lab tests showed metabolic alkalosis with severe hypokalemia(K+ 1.8mmol/L), so fluid therapy was initiated for hydroelectrolytic replacement. During the patient's stay in the ED, two episodes of polymorphic ventricular tachychardia "Torsades de Pointes" (PVT-TDP) occurred, leading to cardiac arrest and requiring electrical cardioversion to restore sinus rhythm, in addition to a temporary pacemaker placement. Telemetry showed a corrected QT interval of >500ms, compatible with Long QT Syndrome(LQTS). Once the patient was hemodynamically stabilized a gastroscopy was performed. The intragastric balloon located in the fundus was removed using an extraction kit, puncturing and aspirating 500ml of saline solution, and extracting the collapsed balloon without any complications. The patient achieved an adequate oral intake afterwards, and no recurrence of emetic episodes were noticed. Previous ECGs revealed a prolonged QT interval and a genetic study confirmed a congenital type 1 LQTS. Treatment was initiated with beta-blockers and a bicameral automatic defibrillator was implanted in order to prevent recurrences. Intragastric balloon placement is generally a safe procedure, serious complications present in 0.70% of cases(2). It is essential to have a proper pre-endoscopic evaluation, including patient's medical history and comorbidities. Episodes of PVT-TDP may present precipitated by certain medications (eg. metoclopramide) or hydroelectrolytic imbalances (eg, hypokalemia)(3). A standardized evaluation of ECG before intragastric balloon placement may be useful to prevent these rare but serious complications.

The toxicological spectrum of the Bacillus cereus toxin cereulide points towards niche-specific specialisation.

Most microbes share their environmental niches with very different forms of life thereby engaging in specialised relationships to enable their persistence. The bacterium Bacillus cereus occurs ubiquitously in the environment with certain strain backgrounds causing foodborne and opportunistic infections in humans. The emetic lineage of B. cereus is capable of producing the toxin cereulide, which evokes emetic illnesses. Although food products favouring the accumulation of cereulide are known, the ecological role of cereulide and the environmental niche of emetic B. cereus remain elusive. To better understand the ecology of cereulide-producing B. cereus, we systematically assayed the toxicological spectrum of cereulide on a variety of organisms belonging to different kingdoms. As cereulide is a potassium ionophore, we further tested the effect of environmental potassium levels on the action of cereulide. We found that adverse effects of cereulide exposure are species-specific, which can be exacerbated with increased environmental potassium. Additionally, we demonstrate that cereulide is produced within an insect cadaver indicating its potential ecological function for a saprophytic lifestyle. Collectively, distinct cereulide susceptibilities of other organisms may reflect its role in enabling competitive niche specialization of emetic B. cereus.

Bacillus cereus: A review of "fried rice syndrome" causative agents.

"Fried rice syndrome" originated from the first exposure to a fried rice dish contaminated with Bacillus cereus. This review compiles available data on the prevalence of B. cereus outbreak cases that occurred between 1984 and 2019. The outcome of B. cereus illness varies dramatically depending on the pathogenic strain encounter and the host's immune system. B. cereus causes a self-limiting, diarrheal illness caused by heat-resistant enterotoxin proteins, and an emetic illness caused by the deadly toxin named cereulide. The toxins together with their extrinsic factors are discussed. The possibility of more contamination of B. cereus in protein-rich food has also been shown. Therefore, the aim of this review is to summarize the available data, focusing mainly on B. cereus physiology as the causative agent for "fried rice syndrome." This review emphasizes the prevalence of B. cereus in starchy food contamination and outbreak cases reported, the virulence of both enterotoxins and emetic toxins produced, and the possibility of contaminated in protein-rich food. The impact of emetic or enterotoxin-producing B. cereus on public health cannot be neglected. Thus, it is essential to constantly monitor for B. cereus contamination during food handling and hygiene practices for food product preparation.

2023 updated MASCC/ESMO consensus recommendations: prevention of nausea and vomiting following high-emetic-risk antineoplastic agents.

PURPOSE: This systematic review updates the MASCC/ESMO recommendations for high-emetic-risk chemotherapy (HEC) published in 2016-2017. HEC still includes cisplatin, carmustine, dacarbazine, mechlorethamine, streptozocin, and cyclophosphamide in doses of > 1500 mg/m2 and the combination of cyclophosphamide and an anthracycline (AC) in women with breast cancer. METHODS: A systematic review report following the PRISMA guidelines of the literature from January 1, 2015, until February 1, 2023, was performed. PubMed (Ovid), Scopus (Google), and the Cochrane Database of Systematic Reviews were searched. The literature search was limited to randomized controlled trials, systematic reviews, and meta-analyses. RESULTS: Forty-six new references were determined to be relevant. The main topics identified were (1) steroid-sparing regimens, (2) olanzapine-containing regimens, and (3) other issues such as comparisons of antiemetics of the same drug class, intravenous NK1 receptor antagonists, and potentially new antiemetics. Five updated recommendations are presented. CONCLUSION: There is no need to prescribe steroids (dexamethasone) beyond day 1 after AC HEC, whereas a 4-day regimen is recommended in non-AC HEC. Olanzapine is now recommended as a fixed part of a four-drug prophylactic antiemetic regimen in both non-AC and AC HEC. No major differences between 5-HT3 receptor antagonists or between NK1 receptor antagonists were identified. No new antiemetic agents qualified for inclusion in the updated recommendations.

Emetic risk classification and evaluation of the emetogenicity of antineoplastic agents-updated MASCC/ESMO consensus recommendation.

PURPOSE: Our goal was to identify new anticancer agents approved by the US Food and Drug Administration (FDA) and the European Medical Agency (EMA) since the 2016 MASCC/ESMO antiemetic update and classify their emetic potential. METHODS: The MASCC/ESMO Expert Panel classified the emetogenicity of the identified new antineoplastic agents based on nonsystematic reviews of randomized controlled trials, analysis of product labeling, and evaluation of emetic classification in other international guidelines and informal consensus. The emetogenic classification system for oral anticancer agents was revised into two emetic risk categories (minimal-low; moderate-high) to be consistent with the system reported by ASCO (American Society of Clinical Oncology) in their 2017 guideline update. The previously employed four emetic risk classification categories for intravenously administered antineoplastic agents were retained for this update. RESULTS: From June 2015 to January 2023, 107 new antineoplastic agents (44 intravenously administered and 63 orally administered agents) were identified. The reported incidence of vomiting varied significantly across studies for many agents, especially for oral anticancer agents. CONCLUSION: The MASCC/ESMO Expert Panel acknowledges the limitations of our efforts to classify the emetic potential of anticancer agents, especially the imprecision associated with oral agents. However, we have attempted to provide a reasonable approximation of the emetic risk associated with new antineoplastic agents by searching the available literature and reviewing other available international antiemetic guidelines.

2023 Updated MASCC/ESMO Consensus Recommendations: prevention of radiotherapy- and chemoradiotherapy-induced nausea and vomiting.

PURPOSE: Radiotherapy and chemoradiotherapy-induced nausea and vomiting (RINV and C-RINV) are common and distressing, and there is a need for guidance for clinicians to provide up to date optimal antiemetic prophylaxis and treatment. Through a comprehensive review of the literature concerning RINV and C-RINV, this manuscript aims to update the evidence for antiemetic prophylaxis and rescue therapy and provide a new edition of recommendations for the MASCC/ESMO antiemetic guidelines for RINV and C-RINV. METHODS: A systematic review of the literature including data published from May 1, 2015, to January 31, 2023, was performed. All authors assessed the literature. RESULTS: The searches yielded 343 references; 37 met criteria for full article review, and 20 were ultimately retained. Only one randomized study in chemoradiation had the impact to provide new recommendations for the antiemetic guideline. Based on expert consensus, it was decided to change the recommendation for the "low emetic risk" category from "prophylaxis or rescue" to "rescue" only, while the drugs of choice remain unchanged. CONCLUSION: As for the previous guideline, the serotonin receptor antagonists are still the cornerstone in antiemetic prophylaxis of nausea and vomiting induced by high and moderate emetic risk radiotherapy. The guideline update provides new recommendation for the management of C-RINV for radiotherapy and concomitant weekly cisplatin. To avoid overtreatment, antiemetic prophylaxis is no longer recommended for the "low emetic risk" category.

2023 updated MASCC/ESMO consensus recommendations: controlling nausea and vomiting with chemotherapy of low or minimal emetic potential.

PURPOSE: Review the literature to update the MASCC guidelines from 2016 for controlling nausea and vomiting with systemic cancer treatment of low and minimal emetic potential. METHODS: A working group performed a systematic literature review using Medline, Embase, and Scopus databases between June 2015 and January 2023 of the management of antiemetic prophylaxis for anticancer therapy of low or minimal emetic potential. A consensus committee reviewed recommendations and required a consensus of 67% or greater and a change in outcome of at least 10%. RESULTS: Of 293 papers identified, 15 had information about managing systemic cancer treatment regimens of low or minimal emetic potential and/or compliance with previous management recommendations. No new evidence was reported that would change the current MASCC recommendations. No antiemetic prophylaxis is recommended for minimal emetic potential therapy, and single agents recommended for low emetic potential chemotherapy for acute emesis, but no prophylaxis is recommended for delayed emesis. Commonly, rescue medication includes antiemetics prescribed for the next higher level of emesis. CONCLUSION: There is insufficient data to change the current guidelines. Future studies should seek to more accurately determine the risk of emesis with LEC beyond the emetogenicity of the chemotherapy to include patient-related risk assessment.

2023 updated MASCC/ESMO Consensus recommendations: Prevention of nausea and vomiting following moderately emetic risk antineoplastic agents.

PURPOSE: Review the literature to update the MASCC guidelines from 2015 for controlling nausea and vomiting with systemic cancer treatment of moderate emetic potential. METHODS: A systematic literature review was completed using Medline, Embase, and Scopus databases. The literature search was done from June 2015 to January 2023 of the management of antiemetic prophylaxis for anticancer therapy of moderate emetic potential. RESULTS: Of 342 papers identified, 19 were relevant to update recommendations about managing antiemetic prophylaxis for systemic cancer treatment regimens of moderate emetic potential. Important practice changing updates include the use of emetic prophylaxis based on a triple combination of neurokinin (NK)1 receptor antagonist, 5-HT3 receptor antagonist, and steroids for patients undergoing carboplatin (AUC ≥ 5) and women < 50 years of age receiving oxaliplatin-based treatment. A double combination of 5-HT3 receptor antagonist and steroids remains the recommended prophylaxis for other MEC. Based on the data in the literature, it is recommended that the administration of steroids should be limited to day 1 in moderately emetogenic chemotherapy regimens, due to the demonstration of non-inferiority between the different regimens. More data is needed on the emetogenicity of new agents at moderate emetogenic risk. Of particular interest would be antiemetic studies with the agents sacituzumab-govitecan and trastuzumab-deruxtecan. Experience to date with these agents indicate an emetogenic potential comparable to carboplatin > AUC 5. Future studies should systematically include patient-related risk assessment in order to define the risk of emesis with MEC beyond the emetogenicity of the chemotherapy and improve the guidelines for new drugs. CONCLUSION: This antiemetic MASCC-ESMO guideline update includes new recommendations considering individual risk factors and the optimization of supportive anti-emetic treatments.

Potential of Thymus and Activation-Regulated Chemokine (TARC) as a Prognostic Biomarker of Food Protein-Induced Enterocolitis Syndrome (FPIES) Caused by Egg Yolk.

BACKGROUND: Several recent studies have reported egg yolk-associated food protein-induced enterocolitis syndrome (FPIES) in Japan. We previously reported the usefulness of post-emetic thymus and activation-regulated chemokine (TARC) levels for the diagnosis and evaluation of symptom severity in FPIES caused by solid foods including egg yolk. However, there are no studies on the usefulness of TARC as a prognostic biomarker. OBJECTIVE: The aim of the study was to evaluate the post-emetic TARC levels, clinical symptoms, and post-index event results of the egg yolk oral food challenge test (OFC), and retrospectively investigate predictive factors of the subsequent OFC result. METHOD: This retrospective study included 12 patients with egg yolk FPIES. The following long-term management protocol for egg yolk FPIES was mandatory for study inclusion: Patients visited the emergency department, met the diagnostic criteria of FPIES, and underwent an egg yolk OFC 6-12 months after complete elimination of egg yolk. If the result of the OFC was positive, the patient underwent the OFC every year until it was negative. We analyzed a total of 20 episodes (12 department visits and eight positive OFCs). The blood test data, including post-emetic TARC level and symptom severity, were compared between the next-OFC-positive group and the next-OFC-negative group. In addition, tolerance development over follow-up was analyzed. RESULTS: The median (range) ages of the next-OFC-positive and negative groups were 11 (6-33) and 10 (7-21) months, respectively. The median (range) serum TARC (pg/mL) level was 5,208 (2,009-8,147) in the next-OFC-positive group, which was significantly higher (p = 0.004) than that in the next-OFC-negative group, which was 1,803 (905-3,754). There were no significant differences in other hematological results. The next-OFC-positive group had greater severity compared to the next-OFC-negative group (p = 0.026). The remission rate was approximately 30% at 24 months and 80% at 36 months. CONCLUSION: Post-emetic TARC levels may predict the short-term prognosis of egg yolk FPIES after approximately 1 year and could be useful for the management of egg yolk FPIES.

Certified nurse specialists in cancer nursing and prophylactic antiemetic prescription for chemotherapy patients.

PURPOSE: The prevention of chemotherapy-induced nausea and vomiting (CINV), a common chemotherapy side effect, should be attempted by oncology nurses. Certified nurses could be certified nurse specialists in cancer nursing (CNSCNs), who have high-level graduate education, or certified nurses in cancer chemotherapy nursing (CNCCNs), who have short-term training. The relationship between these certifications and compliance with the CINV prevention guidelines has not been investigated. We aimed to evaluate the association between certified nurse staffing and prescription of prophylactic antiemetic drugs for chemotherapy patients with high emetic risk. METHODS: We used health service utilisation data for cancer patients diagnosed in 2016 from 474 hospitals nationwide in Japan and a list of certified nurses published by the Japanese Nurse Association. Patients receiving highly emetic chemotherapy were included. A multilevel mixed-effect logistic regression analysis was conducted to estimate the prescription of prophylactic antiemetic drugs associated with CNSCN and/or CNCCN staffing. RESULTS: Data of 46,306 patients were analysed. Overall, 68.4% and 94.0% of the patients received chemotherapy at hospitals with CNSCNs and CNCCNs, respectively. Small cell lung cancer, non-small cell lung cancer, breast cancer, and oesophageal cancer were positively associated with the prescription of recommended antiemetic drugs. CNSCNs was significantly associated with the prescription of prophylactic antiemetic drugs, while CNCCNs was positively but non-significantly associated with antiemetic prescriptions. CONCLUSION: This study is the first to demonstrate that CNSCN placement was significantly associated with prescribing antiemetic drugs recommended by clinical guidelines. Patients are likely to receive appropriate supportive care with the proper placement of CNSCNs.

FLOT (a chemotherapy regimen for gastric/esophagogastric junction cancer): to be treated as a highly emetogenic regimen or a moderately emetogenic one? Comparison of the emetogenic potential of FLOT versus FOLFOX and TAC regimens.

PURPOSE: The current study aimed at investigating the efficacy of aprepitant-containing triple antiemetic regimen in FLOT (fluorouracil + leucovorin + oxaliplatin + docetaxel) recipients as well as the emetogenic potential of FLOT regimen, through comparison of nausea and vomiting rates in a moderately emetogenic chemotherapy, FLOT, and a highly emetogenic chemotherapy recipients. STUDY: Patients planned to receive one of FLOT, FOLFOX (fluorouracil + leucovorin + oxaliplatin/moderate-emetic risk), or TAC (docetaxel + doxorubicin + cyclophosphamide/high-emetic risk) regimens were recruited. All patients were treated with the same triple antiemetic regimen containing aprepitant. RESULTS: A total of 165 chemotherapy-naïve patients (52 FLOT recipients) were eligible to enter the study. At the end of day 5, "complete response" (primary efficacy endpoint) was achieved by 84.6%, 63.5%, and 61.5% of the FLOT-receiving patients in acute, delayed, and overall phases, respectively. A significant difference was seen among the odds of FLOT recipients and FOLFOX recipients concerning "complete response" achievement in delayed (p = 0.014) and overall (p = 0.017) phases, "no emesis" in delayed (p = 0.018) and overall (p = 0.010) phases, and also "complete protection" in acute (p = 0.023), delayed (p = 0.009), and overall (p = 0.006) phases; however, the difference between the odds of FLOT recipients and TAC recipients, in relation to achieving these endpoints, was insignificant. FLOT group showed significantly faster time-to-antiemetic regimen failure and time-to-first emetic episode in comparison with the FOLFOX group, which was insignificant in comparison with the TAC group. CONCLUSION: According to the findings, FLOT has to be considered as a high-emetic-risk regimen; provided that, as recommended by the antiemetic guidelines towards better management of delayed nausea and vomiting induced by highly emetogenic regimens, executing clinical trials concerning the efficacy of continuing dexamethasone on days 2-4 in aprepitant-containing triple antiemetic regimen schedule is required.

A retrospective study on chemotherapy-induced nausea and vomiting in highly/moderately emetogenic chemotherapy: incidence and prescribing practice.

BACKGROUND: Chemotherapy-induced nausea vomiting (CINV) is a common and significant problem in oncology patients and rated as one of cancer chemotherapy's most distressing side effects. The objectives of this study are to describe the incidence of CINV in highly and moderately emetogenic chemotherapy-treated patients and the prescribing pattern of CINV prophylaxis. METHODS: This retrospective, cross-sectional single-center study randomly collected data on demographics, CINV episodes, and prescribing patterns for adult oncology patients receiving intravenous highly or moderately emetogenic chemotherapy (HEC/MEC) between January and December 2019. RESULTS: A total of 419 randomly selected records of HEC/MEC recipients with 2388 total chemotherapy cycles were included. The mean age was 53.6 ± 12.6 years old. The majority was female (66%), Malay (54.4%), diagnosed with cancer stage IV (47.7%), and with no comorbidities (47%). All patients were prescribed with IV granisetron and dexamethasone before chemotherapy for acute prevention, whereas dexamethasone and metoclopramide were prescribed for delayed prevention. Aprepitant was not routinely prescribed for the prevention of CINV. CINV incidence was 57% in the studied population and 20% in the total cycle. This study found a significant association between CINV incidence with performance status and cisplatin-based chemotherapy (OR = 3.071, CI = 1.515-6.223, p = 0.002; OR = 4.587, CI = 1.739-12.099, p = 0.02, respectively). CONCLUSION: CINV incidence was rather high per patient but relatively low per cycle. Most patients were prescribed with dual regimen antiemetic prophylaxis. IMPACT: This study provides evidence that there was suboptimal use of recommended agents for CINV, and there is a clear need for further improvements in CINV management.

Cost-effectiveness analysis of NEPA, a fixed-dose combination of netupitant and palonosetron, for the prevention of highly emetogenic chemotherapy-induced nausea and vomiting: an international perspective.

PURPOSE: The aim of this study was to assess the cost-effectiveness of NEPA, a fixed-dose combination of oral netupitant (300 mg) and palonosetron (0.5 mg), compared to available treatments in Spain after aprepitant generic introduction in the market, and to discuss results in previously performed analyses in different wordwide settings. METHODS: A Markov model including three health states, complete protection, complete response at best and incomplete response, was used to evaluate the cost-effectiveness of NEPA versus common treatment options in Spain during 5 days after chemotherapy. Incremental costs including treatment costs and treatment failure management cost as well as incremental effects including quality adjusted life days (QALDs) and emesis-free days were compared between NEPA and the comparator arms. The primary outcomes were cost per avoided emetic event and cost per QALDs gained. RESULTS: NEPA was dominant (more effective and less costly) against aprepitant combined with palonosetron, and fosaprepitant combined with granisetron, while, compared to generic aprepitant plus ondansetron, NEPA showed an incremental cost per avoided emetic event of €33 and cost per QALD gained of €125. CONCLUSION: By most evaluations, NEPA is a dominant or cost-effective treatment alternative to current antiemetic standards of care in Spain during the first 5 days of chemotherapy treatment in cancer patients, despite the introduction of generics. These results are in line with previously reported analyses throughout different international settings.

Beyond the Psychoactive Effects of Ayahuasca: Cultural and Pharmacological Relevance of Its Emetic and Purging Properties.

The herbal preparation ayahuasca has been an important part of ritual and healing practices, deployed to access invisible worlds in several indigenous groups in the Amazon basin and among mestizo populations of South America. The preparation is usually known to be composed of two main plants, Banisteriopsis caapi and Psychotria viridis, which produce both hallucinogenic and potent purging and emetic effects; currently, these are considered its major pharmacological activities. In recent decades, the psychoactive and visionary effect of ayahuasca has been highly sought after by the shamanic tourism community, which led to the popularization of ayahuasca use globally and to a cultural distancing from its traditional cosmological meanings, including that of purging and emesis. Further, the field of ethnobotany and ethnopharmacology has also produced relatively limited data linking the phytochemical diversity of ayahuasca with the different degrees of its purging and emetic versus psychoactive effects. Similarly, scientific interest has also principally addressed the psychological and mental health effects of ayahuasca, overlooking the cultural and pharmacological importance of the purging and emetic activity. The aim of this review is therefore to shed light on the understudied purging and emetic effect of ayahuasca herbal preparation. It firstly focuses on reviewing the cultural relevance of emesis and purging in the context of Amazonian traditions. Secondly, on the basis of the main known phytochemicals described in the ayahuasca formula, a comprehensive pharmacological evaluation of their emetic and purging properties is presented.

Detection of Bacillus cereus as a causative agent of emetic food poisoning by an unconventional culture procedure.

Bacillus cereus is known to cause two types of food poisoning: emetic and diarrhoeal. Both diseases are usually self-limiting; however, severe cases have been reported, presenting with acute liver failure and encephalopathy, including rarely fatal cases of vomiting. Clinical laboratories do not routinely test for B. cereus in patients with gastrointestinal disease. Therefore, B. cereus causing food poisoning goes undetected. We report a successful isolation of emetic B. cereus from a patient with food poisoning who presented with severe vomiting, fulminant hepatic failure, and acute encephalopathy, by a non-conventional method. Initially, stool specimens from the patients were routinely cultured to identify the causative organisms of food poisoning. No foodborne pathogens were detected in this study. In contrast, additional clinical and epidemiological information strongly suggested food poisoning by emetic B. cereus. Consequently, we allowed Drigalski agar medium smeared with patient stool specimens to stand at room temperature (approximately 25 °C) for 9 days. After 9 days, mixed bacteria grown on the medium were inoculated onto mannitol egg yolk polymyxin (MYP) agar plates, a selective medium for B. cereus. Typical colonies of B. cereus developed on MYP agar plates. The isolated B. cereus had a cereulide-producing genetic locus (ces) gene encoding the emetic toxin cereulide. The method used in this case study was unique. This method is easy to apply after obtaining an additional clinical and epidemiological information, and this method will improve the diagnostic rate of severe B. cereus food poisoning. This will contribute to the advancement of therapeutics in the future.

Impact of a Novel PagR-like Transcriptional Regulator on Cereulide Toxin Synthesis in Emetic Bacillus cereus.

The emetic type of foodborne disease caused by Bacillus cereus is produced by the small peptide toxin cereulide. The genetic locus encoding the Ces nonribosomal peptide synthetase (CesNRPS) multienzyme machinery is located on a 270 kb megaplasmid, designated pCER270, which shares its backbone with the Bacillus anthracis toxin plasmid pXO1. Although the ces genes are plasmid-borne, the chromosomally encoded pleiotropic transcriptional factors CodY and AbrB are key players in the control of ces transcription. Since these proteins only repress cereulide synthesis during earlier growth phases, other factors must be involved in the strict control of ces expression and its embedment in the bacterial life cycle. In silico genome analysis revealed that pCER270 carries a putative ArsR/SmtB family transcription factor showing high homology to PagR from B. anthracis. As PagR plays a crucial role in the regulation of the protective antigen gene pagA, which forms part of anthrax toxin, we used a gene-inactivation approach, combined with electrophoretic mobility shift assays and a bacterial two-hybrid system for dissecting the role of the PagR homologue PagRBc in the regulation of cereulide synthesis. Our results highlight that the plasmid-encoded transcriptional regulator PagRBc plays an important role in the complex and multilayered process of cereulide synthesis.

From cis-Lobeline to trans-Lobeline: Study on the Pharmacodynamics and Isomerization Factors.

Lobeline is an alkaloid derived from the leaves of an Indian tobacco plant (Lobelia inflata), which has been prepared by chemical synthesis. It is classified as a partial nicotinic agonist and has a long history of therapeutic usage ranging from emetic and respiratory stimulant to tobacco smoking cessation agent. The presence of both cis and trans isomers in lobeline is well known, and many studies on the relationship between the structure and pharmacological activity of lobeline and its analogs have been reported. However, it is a remarkable fact that no studies have reported the differences in pharmacological activities between the two isomers. In this article, we found that different degrees of isomerization of lobeline injection have significant differences in respiratory excitatory effects in pentobarbital sodium anesthetized rats. Compared with cis-lobeline injections, the respiratory excitatory effect was significantly reduced by 50.2% after administration of injections which contained 36.9% trans-lobeline. The study on the influencing factors of isomerization between two isomers shown that this isomerization was a one-way isomerism and only converted from cis to trans, where temperature was the catalytic factor and pH was the key factor. This study reports a new discovery. Despite the widespread use of ventilators, first-aid medicines such as nikethamide and lobeline has retired to second line, but as a nonselective antagonist with high affinity for a4b2 and a3b2 nicotinic acetylcholine receptors (nAChRs). In recent years, lobeline has shown great promise as a therapeutic drug for mental addiction and nervous system disorders, such as depression, Alzheimer disease and Parkinson disease. Therefore, we suggest that the differences between two isomers should be concerned in subsequent research papers and applications.

Histamine release from intestinal mast cells induced by staphylococcal enterotoxin A (SEA) evokes vomiting reflex in common marmoset.

Staphylococcal enterotoxins (SEs) produced by Staphylococcus aureus are known as causative agents of emetic food poisoning. We previously demonstrated that SEA binds with submucosal mast cells and evokes mast cell degranulation in a small emetic house musk shrew model. Notably, primates have been recognized as the standard model for emetic assays and analysis of SE emetic activity. However, the mechanism involved in SEA-induced vomiting in primates has not yet been elucidated. In the present study, we established common marmosets as an emetic animal model. Common marmosets were administered classical SEs, including SEA, SEB and SEC, and exhibited multiple vomiting responses. However, a non-emetic staphylococcal superantigen, toxic shock syndrome toxin-1, did not induce emesis in these monkeys. These results indicated that the common marmoset is a useful animal model for assessing the emesis-inducing activity of SEs. Furthermore, histological analysis uncovered that SEA bound with submucosal mast cells and induced mast cell degranulation. Additionally, ex vivo and in vivo pharmacological results showed that SEA-induced histamine release plays a critical role in the vomiting response in common marmosets. The present results suggested that 5-hydroxytryptamine also plays an important role in the transmission of emetic stimulation on the afferent vagus nerve or central nervous system. We conclude that SEA induces histamine release from submucosal mast cells in the gastrointestinal tract and that histamine contributes to the SEA-induced vomiting reflex via the serotonergic nerve and/or other vagus nerve.