Animal Surgery Research Articles

Possible implications of animal models for the assessment of visceral pain.

Acute pain, provoked generally after the activation of peripheral nociceptors, is an adaptive sensory function that alerts the individual to avoid noxious stimuli. However, uncontrolled acute pain has a maladaptive role in sensory activity leading to development of a chronic pain state which persists even after the damage is resolved, or in some cases, in the absence of an initial local acute injury. Huge numbers of people suffer from visceral pain at least once during their life span, leading to substantial health care costs. Although studies reporting on the mechanism of visceral pain are accumulating, it is still not precisely understood. Therefore, this review aims to elucidate the mechanism of visceral pain through an evaluation of different animal models and their application to develop novel therapeutic approaches for treating visceral pain. To assess the nociceptive responses in viscera, several visceral pain models such as inflammatory, traction, stress and genetic models utilizing different methods of measurement have been devised. Among them, the inflammatory and traction models are widely used for studying the visceral pain mechanism of different disease conditions and post‐operative surgery in humans and animals. A hapten, 2,4,6‐trinitrobenzene sulfonic acid (TNBS), has been extensively used as an inflammatory agent to induce visceral pain. The traction model seems to cause a strong pain stimulation and autonomic reaction and could thus be the most appropriate model for studying the underlying visceral pain mechanism and for probing the therapeutic efficacies of various anesthetic and analgesics for the treatment of visceral pain and hyperalgesia.

Validation of Training and Acquisition of Surgical Skills in Veterinary Laparoscopic Surgery: A Review.

At present, veterinary laparoscopic surgery training is lacking in experiences that provide a controlled and safe environment where surgeons can practice specific techniques while receiving experts' feedback. Surgical skills acquired using simulators must be certified and transferable to the operating room. Most models for practicing laparoscopic skills in veterinary minimally invasive surgery are general task trainers and consist of boxes (simulators) designed for training human surgery. These simulators exhibit several limitations, including anatomic species and procedural differences, as well as general psychomotor training rather than in vivo skill recreation. In this paper, we review the existing methods of training, evaluation, and validation of technical skills in veterinary laparoscopic surgery. Content includes global and specific scales, and the conditions a structured curriculum should meet for improving the performance of novice surgeons during and after training. A focus on trainee-specific assessment and tailored-technical instruction should influence training programs. We provide a comprehensive analysis of current theories and concepts related to the evaluation and validation of simulators for training laparoscopic surgery in small animal surgery. We also highlight the need to develop new training models and complementary evaluation scales for the validation of training and acquisition of basic and advanced skills in veterinary laparoscopic surgery.

Experience of Practicing Veterinarians with Supervising Final-Year Students and New Graduates in Performing Desexing Surgeries

With increasing pressure on university teaching hospital caseloads, veterinary students are increasingly being taught basic desexing skills during their final-year extramural rotations or as new graduates in practice. A cross-sectional survey of New Zealand veterinarians was conducted to elicit information about their experiences supervising these cohorts. Of the 162 respondents who had supervised at least one final-year veterinary student, only 95 (58.6%) allowed students to perform desexing surgeries and the most common procedures they allowed students to perform were cat neuters (96%) followed by cat spays (64%), dog neuters (63%), and dog spays (24%). The time needed to supervise students, the liability of students operating on client-owned animals, and students' poor basic instrument, tissue, and suture handling skills were cited as major deterrents. Breaks in sterility and dropped pedicles were the most frequently reported complications, although these still occurred only occasionally or rarely. Of the 101 respondents who had supervised at least one new graduate, all but one provided surgical mentoring. It took an average of 3.3 dog neuters, 8 dog spays, 2.4 cat neuters, and 4.7 cat spays before respondents were comfortable letting new graduates perform surgery unassisted. Respondents generally expected new graduates to perform dog spays in under 60 minutes, cats spays and dog neuters in under 30 minutes, and cat neuters in under 10 minutes. Although most respondents agreed that students needed more hands-on experience with live animal surgery, the main clinical skills deficiencies identified were ones that could easily be trained and practiced on simulated models.

Common Sources of Pre-, Peri- and Post Surgical Site Infections (SSI) in Dogs during Clinical Students’ Surgical Practice

Surgical site infections (SSI) are important complication of Veterinary surgery. Pre, intra-, and post-surgical procedures are considered to be associated with SSI. An attempt to characterize veterinary SSI in small animal surgery practical was made. 15 dogs were grouped into 5 groups (with each group consisting of 3 dogs), in which skin-defect correction, caudectomy, cystotomy, orchidectomy, or ovariohysterectomy were performed by veterinary students under the guidance of qualified surgeons. Blood samples were obtained pre- and post-surgery. 120 swabs were taken from the following sites; students’ or surgeons’ hands (pre-/post-scrubbing), surgical tables, dog skin, random areas on surgical packs, kennels, and floors of surgical theatre. The microorganisms isolated were as follows; Staphylococcus aureus, Klebsiella spp, Micrococcus luteus, Enterobacter spp, and Bacillus subtilis, with Klebsiella being the highest. Leukocytosis, neutrophilia, monocytosis, increased bands, leukocytopenia, neutropenia, and lymphopenia were observed, with all being signs of infection. This study showed that the sources of SSI were numerous, including the followings; the dogs’ skin microflora, the students’ hands, surgical theater, surgical team, and the kennel. Proper scrubbing techniques should be adopted and maintained. The sterile field created should be kept and proper disinfection of the kennel should be ensured before returning the dogs after surgery.

Effect of a Spay Simulator on Student Competence and Anxiety

Spay simulation has gained attention at colleges of veterinary medicine that seek to utilize low-cost models in lieu of more cost-prohibitive high-fidelity devices or cadaveric specimens. A spay simulator was developed to provide veterinary students at the University of Florida College of Veterinary Medicine a reusable, inexpensive, and error-enabled device for self-practice in anticipation of a live canine ovariohysterectomy. Seventy-four students were recruited, half of whom participated in spay simulation training. A survey was designed to capture students' state and trait anxiety, as well as their self-assessed perceived levels of competence, confidence, and knowledge of anatomy, before and after their live animal surgery. During the live surgical laboratories, surgical competencies were assessed using the Objective Structured Assessment of Technical Skills (OSATS) for operative performance. We hypothesized that the spay simulation training group would have higher reported levels of competence, confidence, and knowledge of anatomy. Additionally, students enrolled in spay simulation training were expected to exhibit a lower level of post-operative anxiety and higher OSATS scores compared with the control group. Results demonstrated a significant increase in perceived anatomical knowledge and improvement in perceived competence level following spay simulation training as compared with the control group. Areas of no difference included perceived confidence, OSATS scores, and overall level of anxiety. The results of this study demonstrate that this low-fidelity spay simulator has a unique place in student surgical training, producing novice surgeons with increased perceived competence and knowledge of anatomy following spay simulation training and live animal surgery.

A starting kit for training and establishing in vivo electrophysiology, intracranial pharmacology, and optogenetics

BackgroundIn accordance with the three R principles of research, animal usage should be limited as much as possible. Especially for the training of entry-level scientists in surgical techniques underlying opto- and electrophysiology, alternative training tools are required before moving on to live animals. We have developed a cost-effective rat brain model for training a wide range of surgical techniques, including, but not limited to optogenetics, electrophysiology, and intracranial pharmacological treatments. ResultsOur brain model creates a realistic training experience in animal surgery. The success of the surgeries (e.g. implantation accuracy) is readily assessable in cross sections of the model brain. Moreover, the model allows practicing electrophysiological recordings as well as testing for movement or light related artefacts. Comparison with Existing Method(s)The surgery and recording experience in our model closely resembles that in an actual rat in terms of the necessary techniques, considerations and time span. A few differences to an actual rat brain slightly reduce the difficulty in our model compared to a live animal. Thus, entry level scientists can first learn basic techniques in our model before moving on to the slightly more complex procedures in live animals. ConclusionsOur brain model is a useful training tool to equip scientist who are new in the field of electrophysiology and optogenetic manipulations with a basic skill set before applying it in live animals. It can be adapted to fit the desired training content or even to serve in testing and optimizing new lab equipment for more senior scientists.

Predicting the duration of surgery and procedures in a veterinary referral center.

To evaluate the ability of veterinary personnel to predict the duration of surgery and associated procedures in a referral center. Prospective observational study. Experienced surgeons (ES; n = 2, board certified for 10+ years), inexperienced surgeons (IS; n = 2, residency completed, not board certified), anesthesia animal health technicians (AAHT; n = 3) and surgery animal health technicians (SAHT; n = 2). Surgeons and technicians predicted surgery duration (skin incision to final stitch/staple) and total procedure duration (TPD; from induction of anesthesia to extubation). Predictions were compared to actual durations with Bland-Altman plots to assess agreement (accuracy) as indicated by bias (mean of observed differences) and limits of agreement (LOA; bias ±1.96 SD). All groups underestimated TPD. Experienced surgeons predicted their own TPD more accurately (bias -20.1 ± 30.4 minutes [±SD]) and more consistently (narrower LOA) than IS for their own TPD (-40.1 ± 41.0 minutes). Experienced surgeon TPD predictions by AAHT were more accurate than those by ES (bias -16.0 ± 28.9 minutes, LOA 5% narrower). Inexperienced surgeon TPD predictions by AAHT were less consistent (wider LOA) than those by IS. Own surgery duration predictions by surgeons were similar in magnitude (ES surgery duration [ESSD] 8.3 ± 18.3, IS surgery duration [ISSD] surgery duration -7.9 ± 27.2 minutes), with greater consistency by ES (LOA 30% narrower). Anesthesia animal health technician predictions were similar to those of surgeons (ESSD 3.0 ± 19.3, ISSD -9.0 ± 28.7 minutes). Surgery animal health technician predictions were similar to those of AAHT for ESSD but were less accurate for ISSD. Surgery duration was more accurately predicted than TPD, which was most accurately predicted by anesthesia technicians. Surgical procedure planning should involve personnel best able to predict total procedure durations; in this case, anesthesia technicians. Accurate planning will promote efficient operating room and personnel use.

An Overlooked Entities in Small Animal Surgery: Splenic Disorders

An Overlooked Entities in Small Animal Surgery: Splenic Disorders

Biological characteristics of dynamic expression of nerve regeneration related growth factors in dorsal root ganglia after peripheral nerve injury.

The regenerative capacity of peripheral nerves is limited after nerve injury. A number of growth factors modulate many cellular behaviors, such as proliferation and migration, and may contribute to nerve repair and regeneration. Our previous study observed the dynamic changes of genes in L4-6 dorsal root ganglion after rat sciatic nerve crush using transcriptome sequencing. Our current study focused on upstream growth factors and found that a total of 19 upstream growth factors were dysregulated in dorsal root ganglions at 3, 9 hours, 1, 4, or 7 days after nerve crush, compared with the 0 hour control. Thirty-six rat models of sciatic nerve crush injury were prepared as described previously. Then, they were divided into six groups to measure the expression changes of representative genes at 0, 3, 9 hours, 1, 4 or 7 days post crush. Our current study measured the expression levels of representative upstream growth factors, including nerve growth factor, brain-derived neurotrophic factor, fibroblast growth factor 2 and amphiregulin genes, and explored critical signaling pathways and biological process through bioinformatic analysis. Our data revealed that many of these dysregulated upstream growth factors, including nerve growth factor, brain-derived neurotrophic factor, fibroblast growth factor 2 and amphiregulin, participated in tissue remodeling and axon growth-related biological processes Therefore, the experiment described the expression pattern of upstream growth factors in the dorsal root ganglia after peripheral nerve injury. Bioinformatic analysis revealed growth factors that may promote repair and regeneration of damaged peripheral nerves. All animal surgery procedures were performed in accordance with Institutional Animal Care Guidelines of Nantong University and ethically approved by the Administration Committee of Experimental Animals, China (approval No. 20170302-017) on March 2, 2017.

Successful treatment of cutaneous solid type adenocarcinoma with cryosurgery in a Pekingese dog

The aim of this study is to defined the treatment of cutaneous solid type adenocarcinoma in a Pekingese dog using cryotherapy. A 3.5 years old intact female Pekingese dog was referred to the small animal surgery clinic. The first neoplasm localization was dorsal to the vulva and the others were bilateral to the vulva. The shape of the nodules were circular. The nodule diameters were 1.8, 1.5, and 1.2 cm. In cross section, the nodules were whitish-yellow in colour, of solid consistency, and characterized by thickening of the skin. The probe-based cryosurgical system was used for cryoablation, using local anesthetic as the interface for uniform freezing. Based on histopathological features, the dog was diagnosed with solid type perianal adenocarcinoma. In conclusion, cryosurgery can be a potent alternate treatment for pleasant, nodular perianal cutaneous adenocarcinoma in animals, particularly those not suited for operation, or whose owners refuse to have them undergo operation.

When your duty of care extends beyond the patient to the client

![Graphic][1] Emma Huntley is a fourth-year veterinary student studying at the University of Surrey. She has a special interest in small animal surgery and hopes to pursue a career in...

A survey of criteria used to evaluate applications for small animal surgery residency positions.

To determine attributes of applicants to small animal surgery residency programs (SRP) that are considered important, favorable, or detrimental according to surgeons at SRP registered with the American College of Veterinary Surgeons (ACVS). Online survey. Residency-trained surgeons at ACVS-registered SRP. An online survey was advertised to eligible surgeons. Respondents anonymously provided information about their professional backgrounds and SRP interview practices and rated candidate attributes in terms of importance during application screening and favorable or detrimental effects during selection or ranking. Responses were compared by respondent practice setting and sex. Surveys were completed by 148 of 289 (51%) invited surgeons. Male and female surgeons were equally represented, and 61% worked in academia. Most respondents' SRP offered in-person interviews, typically to a select applicant group from whom residents were ultimately chosen. Letters of recommendation were the most influential factor in all phases of application review, particularly when respondents knew the writers. Other critical attributes were academic record, internship reputation, research activity, and indices of interpersonal skills. Nearly all respondents considered multiple prior unsuccessful applications detrimental. Academic respondents emphasized academic performance and academic internships; private practice respondents valued personal contact with applicants and surgical specialty internships. Responses did not differ by self-identified gender. Surgery residency program surgeons preferred first- or second-time applicants with excellent academic credentials, specific internship and research experiences, and letters of support from trusted colleagues as well as strong interpersonal skills. Prospective residents can use this information to assess their candidacies, identify potential weaknesses, and prepare competitive applications.

Application of the flipped classroom based on micro-class in animal surgery teaching: An case study of debridement course

Objective To investigate the application of the flipped classroom based on micro-class versus traditional class in animal surgery teaching, and to provide new thinkings for animal surgery teaching. Methods A total of 120 undergraduates from Navy Medical University were randomly divided into control group (class A) and experimental group (class B). The students in class A received traditional teaching, and those in class B received flipped classroom teaching. Questionnaire survey and course assessment were performed after teaching, and a comparative analysis was also performed. Results The self-assessment survey showed that 88.3%, 73.3%, 71.6%, 48.3%, and 73.3% of the students in class A (traditional teaching) filled in the questionnaire with Very Helpful and Helpful, while 91.7%, 85.0%, 83.3%, 78.3%, and 75.0% of the students in class B (flipped classroom teaching) filled in with Very Helpful and Helpful; class B gave better overall evaluation of teaching model than that of class A. The mean total score of class B was 0.91, higher than that of class A (8.43 vs. 7.52, P<0.05), and the mean total score of examination papers in class B was 10.92, higher than that in class A (101.13 vs. 90.21, P<0.05). Conclusion Flipped classroom based on micro-class could improve the teaching effect of debridement course on animal surgery and increase students' self-learning ability. Key words: Micro-class; Flipped classroom; Animal surgery; Debridement

Faculty Perspectives Regarding Day One-Ready Examination Items.

The objective of this mixed-methods, cross-sectional study was to evaluate faculty perspectives regarding Day One-Ready (DOR) content on examination questions given to students at a veterinary medical college and to elucidate whether differing viewpoints on what information constitutes DOR knowledge exist among different veterinary disciplines. Twelve faculty members at a veterinary medical college from three different disciplines (small animal internal medicine, surgery, and primary care) reviewed examination questions given to veterinary students, answered the questions, and stated whether they tested DOR information. After elimination of items not answered by all respondents and after reviewing for question quality, 103 questions remained for analysis. An evaluator from each discipline participated in a discussion about DOR content. Of the questions, 30% were unanimously considered to assess DOR information. No association was found between type of question (medicine, surgery, uncategorized) and whether it was considered DOR. Primary care doctors assessed more questions as testing DOR information than either type of specialist. Questions answered correctly were more likely to be assessed as DOR. During discussion, themes identified with DOR information included common conditions, practical diagnostics, critical knowledge, and discriminating between differential diagnoses. Specialists and primary care doctors differed in their assessment of DOR questions. Veterinary faculty should carefully consider whether examination questions contain DOR information and are appropriate for testing knowledge of the entry-level veterinarian.

Inhalant Self-Administration of Methamphetamine: The Most Similar Model to Human Methamphetamine Addiction

Background: Methamphetamine (meth) is recognized as a highly addictive psychostimulant. Currently, there are no available treatments for meth abuse, and no animal model of meth self-administration has been proposed to represent human meth self-administration. Objectives: We aimed to develop a model to study meth self-administration through inhalation in rats. Methods: Rats were placed in an inhaler apparatus (designed specifically for this purpose) for 15 min per day over two weeks. There were two levers in the cage. Pressing the passive lever had no outcomes. Whereas, for each active lever pressing, an infusion pump delivered 50 μL of meth or distilled water within two seconds. Meth was evaporated on a hot plate adjacent to the rat cage. After loading the drug over the hot plate, the blower fan was run, and the vaporized drug was blown by the fan into the rat cage. Then, meth-induced conditioned place preference and locomotor activity were assessed following 14 days of meth inhalation. The serum concentration of meth was also determined by gas chromatography-mass spectrometry. Results: In this model, the self-administration of meth through inhalation significantly increased locomotor activity, conditioned place preference, and plasma level of meth. Conclusions: We can conclude that the self-administration of meth through inhalation is a novel and effective route of self-administration. Our new protocol presents a promising tool for examining drug-seeking/taking behaviors and neural consequences in a noninvasive approach to reduce the stress of surgery and injection in laboratory animals and increase the validity of animal experiments.

Retalho em avanço de padrão subdérmico para reconstrução de focinho após lesão traumática em canino: relato de caso

Reconstructive plastic surgery in companion animals is increasing in surgical blocks. Pedicle skin flaps on the face of dogs and cats are of difficult execution, making it challenging for the surgeon. The objective of this work is to report a skin reconstruction of a dog's face after trauma. A male dog of unknown breed, presenting trauma of unknown cause with total loss of snout and part of incisive bone, was attended at the Veterinary Hospital of the Federal University of Para, Brazil. Emergency care was performed and the animal was referred for surgical debridement of the lesion and posterior plastic correction. A subcutaneous facial advancement flap was used to cover the wound, demonstrating that this is a good option in this region due to the low elasticity of the skin. There were no intercurrences in the postoperative period and the animal presented good functional and cosmetic results.

ALDH1A3 Regulations of Matricellular Proteins Promote Vascular Smooth Muscle Cell Proliferation.

SummaryVascular smooth muscle cell (VSMC) proliferation promotes intimal hyperplasia (IH) in occluding vascular diseases. Here we identified a positive role of ALDH1A3 (an aldehyde dehydrogenase) in this pro-IH process. The expression of ALDH1A3, but not that of 18 other isoforms of the ALDH family, was substantially increased in cytokine-stimulated VSMCs. PDGF(BB) stimulated VSMC total ALDH activity and proliferation, whereas ALDH1A3 silencing abolished this effect. ALDH1A3 silencing also diminished the expression of two matricellular proteins (TNC1 and ESM1), revealing a previously unrecognized ALDH1A3 function. Loss-of-function experiments demonstrated that TNC1 and ESM1 mediated ALDH1A3's pro-proliferative function via activation of AKT/mTOR and/or MEK/ERK pathways. Furthermore, ALDH inhibition with disulfiram blocked VSMC proliferation/migration in vitro and decreased TNC1 and ESM1 and IH in angioplasty-injured rat carotid arteries. Thus, ALDH1A3 promotes VSMC proliferation at least partially through TNC1/ESM1 upregulation; dampening excessive ALDH1A3 activity represents a potential approach to IH mitigation.

Intestinal surgery in small animals: historical foundations, current thinking, and future horizons.

Intestinal wounds require precise closure after intestinal biopsy, enterotomy, or enterectomy in small animals. Preexisting factors such as intra-abdominal sepsis and hypoalbuminemia as well as poor surgical technique increase the risk of intestinal dehiscence, with considerable negative impact on patient morbidity and mortality. Live dog studies have demonstrated the dangers of mucosal eversion especially in the septic abdomen. Approximating patterns preserve luminal diameter, heal optimally, and have equal bursting strength compared with inverting patterns after 24 hours. Simple interrupted and simple continuous suture patterns and disposable skin staples are established alternatives for manual wound closure. Knotless quilled suture currently used in laparoscopic gastropexy techniques shows bursting strength equal to monofilament sutures in dog cadaveric intestine. Dehiscence rates with hand sewn vs titanium automated stapling anastomosis are similar in uncomplicated cases; however, auto stapling devices may be the preferred method of anastomosis when preexisting abdominal sepsis is present and when patient size allows it. Regardless of the technique, current standard of care involves leak testing and omental wrapping, followed by early postoperative feeding. The past decade has ushered in an exciting new era of laparoscopic assisted techniques that have the potential to reduce postoperative pain and patient morbidity. An understanding of these applications will establish the future of minimally invasive small animal intestinal surgery for veterinary specialists. In summary, surgeons have a variety of methods at their disposal for optimal clinical outcome in small animal intestinal surgery.

Fundamental principles of rehabilitation and musculoskeletal tissue healing.

ObjectiveTo review fundamental principles of tissue healing and physical rehabilitation as they apply to dogs recovering from cranial cruciate ligament (CCL) surgery.Study designInvited Review.Sample populationNone.MethodsA multidisciplinary group of specialists in small animal surgery, rehabilitation/sports medicine, and human physical and occupational therapy reviewed the currently available evidence for rehabilitation post‐CCL surgery. Because current evidence is limited, this group proposes guidelines for rehabilitation after CCL surgery based on the fundamental principles of tissue healing and physical therapy.ResultsThis Review proposes four fundamental principles of small animal physical rehabilitation based on the foundations of tissue healing and patient‐centric and goal‐oriented therapy. Postoperative rehabilitation programs should be designed such that patient progress is based on individual assessment according to the degree of tissue healing, strength, and achievement of functional goals. Therapists must fully understand phases of tissue healing, reassess the patient frequently, and use clinical reasoning skills to progress treatment appropriately for the individual patient.ConclusionUntil more robust evidence is available to guide treatment protocols, fundamental principles of rehabilitation should ideally be adhered to when providing rehabilitation, including after CCL surgery.Clinical significanceWhile this Review specifically addresses post‐CCL surgery rehabilitation, these fundamental principles should be applied broadly to animals enrolled in rehabilitation programs.

Evaluation of waste anesthetic gas surveillance program and isoflurane exposures during animal and human surgery

Prolonged occupational exposure to waste anesthetic gases may have the potential to cause adverse health effects. Workplace exposure surveillance programs are intended to reduce health risk by evaluating exposures to waste anesthetic gases during surgical procedures. Both the personal breathing-zone and area measurements are used to assess occupational exposure in the operating theater. Direct-reading instruments provide real-time measurements and are useful for identifying leaks and evaluating on-the-spot corrective actions. Passive diffusion monitors quantify occupational exposures over time during surgery. The aim of this study was to evaluate a waste anesthetic gas surveillance program to understand occupational exposures and further improve data collection strategy. For this study, 76 survey reports from 2012 through 2014 were retrospectively reviewed to assess occupational exposures to isoflurane in 58 unique procedural rooms operated by the National Institutes of Health. The surveys included industrial hygiene assessments performed during animal and human surgical procedures. The survey reports were evaluated qualitatively and data from these reports was transcribed for quantitative analysis. Variations in sample strategy were observed between surveys and were attributed to ambiguity in the written surveillance program. The study also evaluated the relationship between isoflurane concentrations and sampling method, sampling location, patient type, or scavenging method. Isoflurane exposures were significantly higher among procedures performed on rodents compared to the patients with a large body mass (humans, non-human primates, and swine) (P < 0.05) and in procedures using the charcoal canister exhaust system compared with the central vacuum exhaust system. In addition, individuals performing the surgical procedure experienced elevated occupational exposures measured by both direct-reading instrument and passive diffusion monitors, that is, exposure was significantly higher as measured at the breathing-zone compared with any area within the room (P < 0.05). The study identified several inconsistencies and shortcomings in the surveillance program. Isoflurane concentrations measured during rodent procedures requires further review of work practices and engineering controls. Overall, the findings provide insights to further improve data collection, monitoring, and control of isoflurane exposures.