Chemical Injury Research Articles

Occupational hazards of Indian shrimp farm workers

The paper reviews a range of global aquaculture health and safety literature to inform and contribute to the development of a socio-economic profile of Indian shrimp farm workers including the occupational hazards and injuries they face. In addition, 60 shrimp farm workers were interviewed from each of the states of Andhra Pradesh, Maharashtra, Gujarat and Tamil Nadu. The study revealed that all shrimp farm workers were male, 58% were migrants, and ages ranged from 23 to 53 years with work experience of 5 to 24 years. Few workers (14%) had no formal schooling and many had secondary-level education. Reported physical hazards were high (93%) followed by biological (82%), chemical (77%), ergonomic (71%) and psycho-social (71%) hazards. The majority of physical injuries reported related to slips, falls and cuts (51%), electric shocks (44%), sunburn (41%), dehydration/headaches (40%) and fractures (27%). Approximately 30%–39% had some chemical injury with skin infections/breathing problems. Indian shrimp farm workers face similar occupational hazards and injuries to shrimp farm workers in other countries. The occupational health and safety of shrimp farm workers should be integrated into the concept of ‘One Health’ to ensure aquaculture sustainability and safe, meaningful and good quality employment to workers.

Ocular Chemical Injuries in Western Saudi Arabia: A Study of the Public's Level of Knowledge and Experience.

Chemical burns are potentially blinding eye injuries and are serious ocular emergencies that necessitate prompt evaluation and treatment. This study aimed to evaluate the knowledge and experience of the current practice of ocular chemical injuries among the general population in western Saudi Arabia. An electronic self-administrated structured survey was distributed among citizens using social media channels in November 2022. This survey includes 929 participants from western Saudi Arabia. Most of the participants were more than 20 years old (82.7%), while females represented 82.7%. Most participants reported an inadequate level of awareness about previous hearing of ocular chemical injury terms compared with their level of knowledge, in which the majority (56.62%) showed a good level of understanding. Female participants, participants 20 years old or older, and Saudis corresponded significantly with a good level of knowledge (p-values <0.001, <0.00, and 0.025, respectively). This study showed a fair level of knowledge compared to awareness, which can be improved by further national studies in the Saudi region. We recommend expanding the studies' findings and developing suitable interventions, like health awareness campaigns about ocular chemical damage and prompt corrective measures.

SENSITIVITY OF BACTERIAL STRAINS ISOLATED IN CASES OF COW MASTITIS TO ANTIBIOTICS AND ESSENTIAL OILS

Mastitis is an inflammatory reaction of the udder caused by microorganisms, chemical or mechanical injuries. Bacterial mastitis, caused by several types of bacteria, is divided into two main groups: contagious mastitis caused by Staphylococcus aureus, Streptococcus agalactiae, Streptococcus dysgalactiae, Mycoplasma bovis and mastitis caused by the ubiquitous bacteria Escherichia coli, Pseudomonas aeruginosa or Proteus spp. Currently, instead of using antibiotics, new strategies are being sought to reduce this clinical health problem. The aim of this study is to determine the sensitivity of bacterial strains causing mastitis to antibiotics and essential oils of oregano (Origanum compactum, Origanum majorana) and thyme (Thymus serpyllum). Mammary gland secretion samples, obtained by mechanical and manual methods, from dairy cows from the Kalesija and Gradačac areas were used. A total of 200 samples from dairy cows in different periods of lactation and age were examined. Mastitis control included determining somatic cells count in milk with the California mastitis test, or counting somatic cells on the Fossomatik apparatus, after which all samples with an increased number of somatic cells were microbiologically tested. Based on the obtained results, it can be concluded that there are justified reasons why the use of essential oils should be considered as an alternative to the use of antibiotics in the therapy of animals suffering from mastitis.

Targeting Ca2+-dependent pathways to promote corneal epithelial wound healing induced by CISD2 deficiency

Chronic epithelial defects of the cornea, which are usually associated with severe dry eye disease, diabetes mellitus, chemical injuries or neurotrophic keratitis, as well as aging, are an unmet clinical need. CDGSH Iron Sulfur Domain 2 (CISD2) is the causative gene for Wolfram syndrome 2 (WFS2; MIM 604928). CISD2 protein is significantly decreased in the corneal epithelium of patients with various corneal epithelial diseases. Here we summarize the most updated publications and discuss the central role of CISD2 in corneal repair, as well as providing new results describing how targeting Ca2+-dependent pathways can improve corneal epithelial regeneration. This review mainly focuses on the following topics. Firstly, an overview of the cornea and of corneal epithelial wound healing. The key players involved in this process, such as Ca2+, various growth factors/cytokines, extracellular matrix remodeling, focal adhesions and proteinases, are briefly discussed. Secondly, it is well known that CISD2 plays an essential role in corneal epithelial regeneration via the maintenance of intracellular Ca2+ homeostasis. CISD2 deficiency dysregulates cytosolic Ca2+, impairs cell proliferation and migration, decreases mitochondrial function and increases oxidative stress. As a consequence, these abnormalities bring about poor epithelial wound healing and this, in turn, will lead to persistent corneal regeneration and limbal progenitor cell exhaustion. Thirdly, CISD2 deficiency induces three distinct Ca2+-dependent pathways, namely the calcineurin, CaMKII and PKCα signaling pathways. Intriguingly, inhibition of each of the Ca2+-dependent pathways seems to reverse cytosolic Ca2+ dysregulation and restore cell migration during corneal wound healing. Notably, cyclosporin, an inhibitor of calcineurin, appears to have a dual effect on both inflammatory and corneal epithelial cells. Finally, corneal transcriptomic analyses have revealed that there are six major functional groupings of differential expression genes when CISD2 deficiency is present: (1) inflammation and cell death; (2) cell proliferation, migration and differentiation; (3) cell adhesion, junction and interaction; (4) Ca2+ homeostasis; (5) wound healing and extracellular matrix; and (6) oxidative stress and aging. This review highlights the importance of CISD2 in corneal epithelial regeneration and identifies the potential of repurposing venerable FDA-approved drugs that target Ca2+-dependent pathways for new uses, namely treating chronic epithelial defects of the cornea.

Pseudonictitating Membrane

A 69-year-old man presented with a membrane over the bulbar conjunctiva in his right eye (OD), encroaching cornea from the temporal side, and freely movable over the conjunctival and corneal surface (A). Extraocular movements were free. The patient had no history of pain, foreign body sensation, lacrimation, chronic illness, prior hospitalization, trauma, adverse drug reaction, or chemical injury. The Schirmer’s test showed normal tear film production. The patient had cataracts in both eyes, otherwise, anterior segment and fundus findings were normal. Uncorrected visual acuity was 6/36 OD and 6/18 in the left eye (OS). Intraocular pressure was 16 mmHg OD and 15 mmHg OS, respectively. Image of OD with membrane in (B) primary gaze, (C) down and out position, and (D) up and inwards (Magnified version of Figure A-D is available online at www.aaojournal.org).

High-Strength Cell Sheets and Vigorous Hydrogels from Mesenchymal Stem Cells Derived from Human Embryonic Stem Cells.

Natural cell derivates, including cell sheets (CSs) and matrix gels, have opened new opportunities to probe questions in tissue engineering and regenerative medicine. However, the potential of CSs and hydrogels generated by current protocols is still limited by the challenges of heterogeneity and weak mechanical properties. Here, we developed a 21 day long-term serum-free culture system for human embryonic stem cell (hESC)-derived immunity-and-matrix-regulatory cells (IMRCs). The CSs formed with IMRCs (IMRC-CSs) have a much greater secretion capacity for the extracellular matrix (ECM) and stronger mechanical properties than umbilical cord-derived MSCs, with a ten thousand-fold increase in elastin, a higher elastic modulus of 1500 kPa, a thicker structure of 20.59 μm, and a higher fiber count per square millimeter. The IMRC-CSs could promote corneal chemical injury repair and could be turned into injectable temperature-sensitive hydrogels for uterine adhesion repair via a decellularization process. In summary, we have established a high-strength CS platform using human pluripotent stem cells for the first time, providing a facile and scalable engineering approach for regenerative medicine.

Using PROKERA® to treat ocular chemical injury caused by animal health disinfectant

&lt;p&gt;OMNICIDE&amp;reg;是一種廣效型動物消毒劑，主要成分包含戊二醛(glutaraldehyde)以及苯扎氯銨(cocobenzyl dimethyl ammonium chloride)。動物消毒劑引起的眼表化學性灼傷在過往的文獻中並未被提及過。在此，我們報告一位57歲的男性，因為誤點動物消毒劑至右眼，造成大範圍結膜水腫，角膜上皮缺損，以及輪狀部缺血，符合Dua分類的第三級。除了傳統的藥物治療外，我們利用角膜生物敷料PROKERA&amp;reg;來穩定眼表發炎反應及促進角膜上皮生長。在治療之後的追蹤過程，角膜上皮完全恢復且患者的視力亦獲得改善。&lt;/p&gt; &lt;p&gt;&amp;nbsp;&lt;/p&gt;&lt;p&gt;OMNICIDE&amp;reg; is a broad-spectrum animal health disinfectant containing glutaral-dehyde and cocobenzyl dimethyl ammonium chloride. Ocular chemical injury caused by animal health disinfectant has never been described in the previous literature. Herein, we presented a 57-year-old man who mis-instilled animal health disinfectant into his right eye. Extensive conjunctival chemosis, large corneal epithelial defect, and limbal ischemia were noted in his right eye with Dua classification grade III. In addition to the conventional medical therapy, we used the biologic corneal bandage device, PROKERA&amp;reg;, to stabilize the ocular surface inflammation and promote corneal re-epithelialization. The corneal epithelial defect healed completely, and the visual acuity improved and remained stable during the follow-up period.&lt;/p&gt; &lt;p&gt;&amp;nbsp;&lt;/p&gt;

Bleach-Induced Chemical Sinusitis and Orbital Cellulitis Following Root Canal Treatment

The authors describe an unusual case of chemical sinusitis and orbital cellulitis secondary to a sodium hypochlorite accident in a patient who had just undergone root canal treatment. The patient presented with acute, progressive symptoms of unilateral maxillary sinusitis, facial cellulitis and orbital cellulitis which began hours after root canal treatment on the ipsilateral side. He was admitted to hospital under the care of the Otorhinolaryngology team and reviewed regularly by the Ophthalmologists. He underwent Endoscopic Sinus Surgery during his hospital stay. The intraoperative findings revealed necrotic sinus mucosa and slough within the involved maxillary sinus, which were suggestive of chemical burn injury induced by the highly alkaline sodium hypochlorite solution used during root canal treatment. He was treated postoperatively with regular nasal toilet, culture-directed antibiotics and topical ocular pressure-lowering eyedrops. He displayed a slow recovery with eventually no orbital sequelae, but experienced persistent cheek numbness three months post-injury. Severe chemical sinusitis with orbital cellulitis secondary to sodium hypochlorite accident is a rare complication of root canal treatment, with potentially severe consequences. It can present with symptoms similar to complicated acute bacterial sinusitis. Otorhinolaryngologists and dental surgeons should maintain a high index of suspicion when managing a patient post-root canal treatment with symptoms of unilateral sinusitis, facial cellulitis, orbital cellulitis and even airway compromise. This would allow prompt intervention before sight or life-threatening complications set in.

Chemical injury for a sexual attack on a minor person: the question of the amendment of other criminal legal measures

In connection with the increase in the number of cases of violent acts related to sexual crimes, some countries have adopted legislation that provides for the use of chemical castration as a criminal-legal measure of a medical nature. The positions of defenders and opponents of the use of this method are analyzed, and the effectiveness of chemical castration as a means of preventing repeated crimes is also investigated. This topic is relevant for justice, medicine and the public, as it concerns serious issues of human rights and the ethics of using medical methods for law enforcement purposes. It can be argued that the introduction of chemical castration will be appropriate to counter the pandemic of sexual crimes against minors, but this issue has many acute angles. It is important not to level the voluntary nature of this procedure by depriving the person of the right to choose. The basis for castration must be a socially dangerous act, the harmful consequences of which must be commensurate with the interference with the normal reproductive activity of a person. Some studies have shown that chemical castration can reduce the risk of repeat crimes related to sexual activity. However, other studies indicate that chemical castration is not a universal means of preventing recidivism, and its effectiveness depends on the specific situation. New research also focuses on the ethical aspects of using chemical castration, including the issues of informed patient consent, possible side effects, and the duration of castration. In addition, it examines whether chemical castration can be used as an alternative to punishment, as is commonly done in criminal law situations. In our opinion, chemical castration is an innovation in the criminal legal field of Ukraine. But it needs thorough discussion and testing in practice. We investigated the issue of sexual crimes against particularly vulnerable persons and followed the changes made to the criminal legislation of Ukraine in recent years.

COMPARISON IN CORNEAL COLLAGEN STRUCTURE BETWEEN 20% PLATELET RICH PLASMA AND 20% AUTOLOGOUS SERUM THERAPY POST NATRIUM HIDROKSIDA EXPOSURE

Objective to compare therapy response between 20% PRP and AS 20% on cornea post sodium hydroxide exposure on collagen structure. Methods this is a true experimental study with post test only design on 18 New Zealand white rabbits. Sample were divided randomly to two groups, each with 9 rabbits. The right eye of each rabbit were exposed to alkali injury with 1N NaOH under general anesthesia. First group was given 20% PRP eyedrops and 20% AS for the second group. And the end of the 7 day periode, all rabbits were euthanized and enucleated to obtain histopthological data. Collagen density, collagen thickness and keratosit cell were evaluated. The result will be analyzed, ratio scale data will be tested with independent T- test, and ordinal scaled data will be tested with Mann-Whitney test. Result The collagen density in the 20% PRP group shows 88.9% grade 2 and 44.4 % grade 2 for the 20% AS group. The collagen thickness in the 20% PRP group is 55.41 and 67.62 for the 20% AS group. The keratosit cell count in the 20% PRP group are 54.56 and 45.47 in the 20% AS group. There is significant difference in the collagen density between 20% PRP and 20% AS treatment (p= 0.066). There is significant difference in the collagen thickness between 20% PRP and 20% AS treatment (p= 0,224). There is significant difference in the keratosit cell count between 20% PRP and 20% AS treatment (p= 0,227). Conclusion From the statistik analysis shows that there is no significant difference in corneal collagen structure between 20% PRP and 20% AS therapy post natrium hidroksida exposure, from our study there is no significant better corneal healing parameters in post alkali chemical ocular injury with 20% PRP eyedrops compare to 20% AS eyedrops.

Ocular Trauma in Children at Women and children Hospital (Hospital Wanita Dan Kanak-Kanak), Sabah, Malaysia

Ocular trauma is a significant health problem in paediatric age group. This study is to evaluate the demographics, etiology, management and visual outcome of paediatric ocular trauma in Sabah. This is a retrospective review of all ocular trauma occurring in the paediatric age group from age 12 years old and below from January to December 2014 at Hospital Wanita Dan Kanak-Kanak, Sabah. Medical records were reviewed and the data was examined based on Birmingham Eye Trauma Terminology (BETT) system. Incomplete case notes were excluded from the study. A total of 37 cases were accumulated during the study period. All the paediatric ocular trauma cases were admitted and accounted for 13.4% of the total paediatric eye ward admission. However, 4 cases were excluded from the study as the medical records were incomplete. There were 26(78.8%) males while 7(21.2%) female children with a ratio male: female of 3.7: 1. There were 31(93.9%) unilateral ocular injury cases while only 2(6.1%) bilateral injury caused by chemical injury. The most common type of ocular trauma was closed globe injury totaling 24 (72.7%) cases. Trauma caused by blunt object contributed to the highest mode of injury 15 (45.5%) of cases. Open globe injuries which had poor visual outcome accounted for 9 (27.3%) cases. Most of patients required surgical treatment 21(63.6%) while 12(36.4%) cases treated non-surgically. In conclusion, ocular trauma was more common in male and pre-school age group. The main aetiology was blunt injury. Most of the cases treated surgically. Poorer visual outcome was observed in open globe injury.

An atypical presentation of sympathetic ophthalmia following chemical ocular burns

BackgroundSympathetic ophthalmia is a rare disease that can present as bilateral granulomatous uveitis after a penetrating trauma or surgery in one eye.FindingsWe report a case of a 47-year-old male with history of decreased vision in the right eye, six months after sustaining severe chemical injury in the left eye. He was diagnosed with sympathetic ophthalmia and was treated with corticosteroids and long-term immunosuppressive therapy, leading to complete resolution of intraocular inflammation. Final visual acuity was 20/30 at one year of follow up.ConclusionsSympathetic Ophthalmia following chemical ocular burns is extremely uncommon. It can present as a diagnostic and therapeutic challenge. It warrants early diagnosis and management.

715 Ocular Complications of Facial Burns in the Pediatric Population

Abstract Introduction Pediatric burns commonly involve the face and periocular areas, with a risk of impairing vision. The aim of this study is to characterize ocular injuries in burn patients and identify the patients at most risk of ocular complications. Methods This study is a retrospective review within a single academic, urban pediatric burn center. All burn patients under 18 years of age admitted from January 2010 to December 2020 with periorbital or ocular involvement were included. Variables analyzed included patient demographics, burn characteristics, presence of ophthalmology consultation, ocular exam findings, follow up time period, and early and late ocular complications. Results In the study period, 2,781 patients were admitted to our burn center, 300 of whom had facial burns involving the eyes and/or eyelids. Etiologies of burn injuries were as follows: 112 (37.5%) scald, 80 (26.8%) flame, 35 (11.7%) contact, 31 (10.4%) chemical, 28 (9.4%) grease, and 13 (4.3%) friction. Overall, 70.9% of patients with ocular burns received an ophthalmology consult. Of these patients, 61.5% had periorbital swelling and 39.8% had corneal injuries. Of the 207 patients who were followed as inpatients by ophthalmology, only 61 (29.5%) presented for a follow-up visit, as recommended, 6 of which had serious ocular sequelae including ectropion, entropion, symblepharon, and corneal decompensation, and 4 of whom had a firework-related injury. Conclusions While burns involving the ocular surface and eyelid margins are infrequent overall, they can lead to long-term sequelae. Ophthalmology consultation is critical, particularly in the setting of chemical and firework-related injury. As ocular and periocular burns can cause immediate as well as delayed sequelae, ophthalmologic evaluation is a key component of assessment. Applicability of Research to Practice This paper characterizes ocular injuries in pediatric patients with facial burn injuries and identifies patients most at risk for ocular complications. We believe this will be valuable for many burn researchers and clinicians in order to better identify patients who could benefit from ophthalmologic evaluation and those at risk for both immediate as well as delayed sequelae from periocular burns.

Lipoxin A4 (LXA4) Reduces Alkali-Induced Corneal Inflammation and Neovascularization and Upregulates a Repair Transcriptome.

To investigate the anti-inflammatory and anti-angiogenic effects of the bioactive lipid mediator LXA4 on a rat model of severe corneal alkali injury. To induce a corneal alkali injury in the right eyes of anesthetized Sprague Dawley rats. They were injured with a Φ 4 mm filter paper disc soaked in 1 N NaOH placed on the center of the cornea. After injury, the rats were treated topically with LXA4 (65 ng/20 μL) or vehicle three times a day for 14 days. Corneal opacity, neovascularization (NV), and hyphema were recorded and evaluated in a blind manner. Pro-inflammatory cytokine expression and genes involved in cornel repair were assayed by RNA sequencing and capillary Western blot. Cornea cell infiltration and monocytes isolated from the blood were analyzed by immunofluorescence and by flow cytometry. Topical treatment with LXA4 for two weeks significantly reduced corneal opacity, NV, and hyphema compared to the vehicle treatment. RNA-seq and Western blot results showed that LXA4 decreased the gene and protein expression of pro-inflammatory cytokines interleukin (IL)-1β and IL-6 and pro-angiogenic mediators matrix metalloproteinase (MMP)-9 and vascular endothelial growth factor (VEGFA). It also induces genes involved in keratinization and ErbB signaling and downregulates immune pathways to stimulate wound healing. Flow cytometry and immunohistochemistry showed significantly less infiltration of neutrophils in the corneas treated with LXA4 compared to vehicle treatment. It also revealed that LXA4 treatment increases the proportion of type 2 macrophages (M2) compared to M1 in blood-isolated monocytes. LXA4 decreases corneal inflammation and NV induced by a strong alkali burn. Its mechanism of action includes inhibition of inflammatory leukocyte infiltration, reduction in cytokine release, suppression of angiogenic factors, and promotion of corneal repair gene expression and macrophage polarization in blood from alkali burn corneas. LXA4 has potential as a therapeutic candidate for severe corneal chemical injuries.

Cicatricial Entropion in Chronic Cicatrizing Conjunctivitis: Potential Pathophysiologic Mechanisms and Long-Term Outcomes of a Modified Technique.

The purpose of this study was to assess the long-term outcomes of severe cicatricial entropion repair with mucous membrane grafting in patients with chronic cicatrizing conjunctivitis and report histopathological changes in the eyelid margin area. Prospective interventional study included 19 patients with severe cicatricial entropion with trichiasis (N = 20 eyelids; 19 upper and 1 lower eyelid) who underwent anterior lamellar recession (with back cuts) and mucous membrane grafting cover for bare anterior tarsus, lid margin, and 2 mm of marginal tarsus, and had a minimum 6 months of follow-up. The anterior lamella and metaplastic eyelid margins were sent for routine Haematoxylin and Eosin and special staining with Masson trichrome stain. The etiologies were chronic Stevens-Johnson syndrome (N = 6), chemical injury (N = 11), and drug-induced pseudopemphigoid (N = 2). Five eyes had undergone entropion correction in the past, and 9 had electroepilation for trichiasis. Entropion was well corrected (without residual trichiasis) in 85% of eyelids with primary surgery. The etiology-wise success rates were 100% for Stevens-Johnson syndrome, 72.7% for chemical injury, and 100% for drug-induced pseudopemphigoid. Three eyelids with failure belonged to chemical injury, and trichiasis in these eyes could be managed with subsequent interventions except in 1 case. All eyelids had no entropion at a mean follow-up of 10.8 months (range, 6-18). Histopathological evaluation of anterior lamella (N = 10) and eyelid margins revealed significant fibrosis in subepithelial, perimysium (muscle of Riolan), and perifollicular areas. Anterior lamellar recession combined with mucous membrane grafting achieves good cicatricial entropion correction except in eyes with chemical injury. The eyelid margins in these eyes have persistent inflammation, and fibrosis involving lash follicles.

Evaluating the Knowledge, Readiness, and Satisfaction Level of Emergency Medical Service Personnel after an Online Chemical Mass Casualty Response Training Program

Introduction:Compared to trauma-based injuries, chemical injuries can inflict widespread and persistent injuries to exposed victims. Emergency medical services (EMS) personnel are vulnerable to chemical injuries. Specialized training is required, including zone setup, personal protective equipment (PPE), decontamination, and antidote use, beyond simple advanced trauma life support. The purpose of this study is to evaluate the educational effectiveness of the online chemical-mass casualty incident response education module (C-MCIREM) for EMS personnel.Method:This study is a retrospective pre-and post-test comparison. Subjects were EMS personnel who enrolled in the C-MCIREM program at the EMS Korea online conference between August 27, 2021 and September 5, 2021. Subjects provided demographic data and completed pre-course and post-course knowledge tests and self-assessments of readiness, as well as a satisfaction survey after the course. For readiness and satisfaction surveys, an 11-point Likert scale was used. The Wilcoxon Rank Sum test was used to compare the two samples.Results:A total of 322 respondents were enrolled. Two-hundred (62.1%) responded that they were most motivated to take the course because of curiosity about the subject. The median pre-course knowledge score was 57/100 (47, 66) and the post-knowledge score was 80/100 (66, 91) (p&lt;0.001). Participants stated they felt their readiness to provide triage, treatment, transport, decontamination, to select correct antidotes, and to use correct PPE (all p&lt;0.001) increased. 90.4% stated they were satisfied with the course. Participants were overall satisfied with the use of the online format (7.71/10 SD 2.05), and were willing to recommend the training to other EMS providers (7.63/10 SD 2.1).Conclusion:The online C-MCIREM program showed high satisfaction with a significant increase in knowledge and self-assessed readiness to respond to a chemical mass casualty incident.

Evaluating the Educational Effectiveness of Hospital Healthcare Providers after Chemical Mass Casualty Response Training Program

Introduction:Chemical exposures can cause direct and indirect injuries to responding medical personnel. Therefore, hospital healthcare providers should be provided with disaster response training that includes identification of chemical hazards, establishment of the hazard zone, personal protective equipment use, decontamination, and chemical injury antidote use. This study evaluates the educational effectiveness of the chemical-mass casualty incident response education module (C-MCIREM) for hospital healthcare providers.Method:This was a retrospective quasi-experimental study. Subjects were hospital providers who enrolled in the C-MCIREM program between May 1, 2021, and July 26, 2022. Subjects were hospital providers from Bucheon, Mokpo, Iksan, Jeonju, and Dae-gu cities in South Korea. Subjects completed pre, post, and three-month knowledge retention and self-assessments of readiness tests, as well as evaluations on tabletop exercises (TTX), and a satisfaction survey (11-point Likert) after the course. The instructors scored teamwork measures via standardized evaluations on TTX throughout the course. The K-paired Sample Friedman test was used to compare samples.Results:127 respondents were enrolled. The median knowledge score rose from 51/100 (39, 66) to 85.5/100 (73.75, 90) with a median retention score of 74/100 (64, 88) (p&lt;0.001). Participants felt their readiness to respond increased in all facets (all p&lt;0.001) on the post and retention test for the MCI situation. All three hospital teams showed significant increases in teamwork between the median of the 1st and 4th TTX as 27/100 (23.5, 29) and 69/100 (66.75, 69.5) (p&lt;0.05). Participants were overall satisfied (9.1/10 SD 1.13) and would recommend the training to others (9.15/10 SD 1.2).Conclusion:C-MCIREM participants had high satisfaction with a significant increase and persistence in knowledge, improved teamwork, and self-assessed readiness to respond to a chemical mass casualty incident.

Chronic Pelvic Pain Develops in Sensory Neuron Conditional Asic3 Null Mice Subjected to Chemical Injury

Sensitization of primary afferents is an important underlying mechanism for visceral hypersensitivity and pain. We investigated the contribution of acid-sensing ion channels (ASICs) in sensory neurons to the development of pain in a model of chemical-induced cystitis. ASICs are assembled as heterotrimers in bladder sensory neurons; however, the deletion of the ASIC3 subunit results in a loss-of-function phenotype with sensory neurons unable to discharge action potentials in response to acidification. In this study, conditional sensory neuron Asic3 knockout (KO) mice ( Asic3 fl/fl ;Avil-Cre +/- ) and control littermates ( Asic3 fl/fl ;Avil-Cre -/- ) received cyclophosphamide (CYP) (IP 80 mg/kg), or saline, every other day for five days. Experimental observations were made after one day (acute) or 14 days (chronic) after the last dose of CYP. In the acute setting, both control and conditional Asic3 KO mice treated with CYP exhibited an irritated bladder phenotype with a high number of voiding events of small volume. However, voiding activity normalized in both groups within two weeks of receiving CYP. In contrast, conditional Asic3 KO mice treated with CYP developed pelvic allodynia that persisted for at least two weeks, whereas control mice had no pain phenotype. In the chronic setting, no apparent edema or inflammatory cells were observed in bladders of control or conditional Asic3 KO mice, indicating that the pelvic allodynia seen in conditional Asic3 KO mice treated with CYP is likely driven by abnormal functioning of the nervous system and not by inflammation. To assess whether, in the chronic setting, the referred pelvic allodynia seen in conditional Asic3 KO mice treated with CYP is caused by sensitized primary afferents, we examined the firing evoked by sustained suprathreshold electrical stimulation of acutely isolated bladder sensory neurons. Sensory neurons were classified based of the sensitivity of the action potential to tetrodotoxin (TTX), as TTX-resistant (TTX-R) or TTX-sensitive (TTX-S). Strikingly, ~ 40% (11/17) of the bladder sensory neurons with TTX-R action potentials from conditional Asic3 KO mice treated with CYP exhibited aberrant firing (i.e., sensitization) in response to suprathreshold stimulation, compared to 3% (1/33) in control mice. These findings indicate that the pelvic allodynia seen in conditional Asic3 KO mice is driven in part by sensitized bladder afferents. Taken together, our studies support the notion that ASICs operate at the nerve terminals to modulate nociceptor excitability and sensitization. This is the full abstract presented at the American Physiology Summit 2023 meeting and is only available in HTML format. There are no additional versions or additional content available for this abstract. Physiology was not involved in the peer review process.

1623 Deconstructing chemical injury response in skin with clinical and bioinformatic data.

1623 Deconstructing chemical injury response in skin with clinical and bioinformatic data.

A Rare Case of a Second-Degree Chemical Burn due to Successive Contacts of Acidic Wart Removal Solution and Paint Solution

Introduction: Chemical burns are an uncommon form of burn injury, accounting for 2.1% to 6.5% of all burn centre admissions. We presented one rare case of a second degree chemical burn due to successive contacts of acidic wart removal solution and paint mixture solution. Case: A 38-year-old male with chemical burn on both feet due to reckless usage of a self-purchased wart removal solution, and accidental contact with paint mixture solution. Our surgeon author diagnosed a superficial partial thickness (second-degree) chemical burn on this patient, and performed surgical debridement followed by hyaluronic-enhanced silver sulfadiazine topical dressing to provide antimicrobial protection to the wound and topical petrolatum-based ointment to maintain moist environment for the wound and the periwound. Our team also gave Ceftaroline, a cephalosporin for serious infections of the skin and tissues below the skin, intravenously. Result: One day after the surgical procedure, the wound dimensions were slightly more extensive than the initial size due to extensive debridement and necrotomy. All wounds produced no or minimal exudate, showed no slough nor pus inside the granulation area, and no swelling nor maceration in the periwound area. The fifth day after the surgical procedure, the wound on the lateral side of patient’s right foot was almost completely covered by epithelialization. The wound on the sole of patient’s right foot was about 70-80% covered by epithelialization, and the wound on the sole of patient’s left foot was also about 70% covered by epithelialization. Discussion: Topical solution for wart removal consists of many chemicals agents (i.e. salicylic acid and acetic acid) and its application should strongly be under guidance and monitoring by physician due to its potential to harm human bodies and trigger chemical burn injury in varying degrees. Paint mixture is usually safe, risks no or minimal harms when in contact with skin, however it can provide a more difficult scenario and consequently a more extensive cleansing during the wound debridement procedure. Immediate decontamination and adequate dilution through massive irrigation is a major determinant of burn severity after chemical injury. Application of 1% silver sulfadiazine topical antibiotics enhanced with 0.2% hyaluronic acid for moisturizer displayed significant improvement for the burn wound healing. Conclusion: Knowing exactly what type of chemical substance in contact with the skin and tissues that caused the chemical burn injury is as equally important as the comprehensive management itself. For acidic burn injuries, a proper and sometimes extensive necrotomy procedure is mandatory to provide a good tissue regeneration.