Clinical presentation and management of atypical hemolytic uremic syndrome in Latin America: a narrative review of the literature.

INTRODUCTION: Comprehensive information about atypical hemolytic uremic syndrome (aHUS) is relatively scarce outside of Europe and North America. This narrative review assembles available published data about the clinical presentation and management of aHUS in Latin America. AREAS COVERED: A search conducted in February 2023 of the MEDLINE (from inception), Embase (from inception), and LILACS/IBECS (1950 to 2023) databases using search terms 'atypical hemolytic uremic syndrome' and 'Latin America' and their variations retrieved 51 records (full papers and conference abstracts) published in English, Spanish, or Portuguese. After de-duplication, manual screening of titles/abstracts and addition of author-known articles, 25 articles were included of which 17 (68%) are full papers. All articles were published during the years 2013-2022. Articles include cohort studies, a registry analysis, and case reports from Argentina, Brazil, Chile and Columbia. Overall, Latin American patients with aHUS present the classic epidemiological, clinical, and genetic characteristics associated with this condition as described in other world regions. Depending on the country and time of reporting, aHUS in Latin America was treated mainly with plasma therapy and/or eculizumab. Where reported, eculizumab substantially improved aHUS-related outcomes in almost all adult and pediatric patients. EXPERT OPINION: Eculizumab has dramatically altered the natural course of aHUS, improving prognosis and patient outcomes. Addressing economic challenges and investing in healthcare infrastructure will be essential to implement strategies for timely detection and early treatment of aHUS in Latin America.

Immediate effect of hallux valgus surgery on the biomechanical behavior of the first ray.

BACKGROUND: The surgical treatment of hallux valgus (HV) deformity has been the subject of countless publications but few focus on the altered windlass mechanism or analyze the biomechanical behavior immediately after surgery. METHODS: Patients treated for HV between January and March 2023 were included. The surgery consisted of a L-reverse first metatarsal osteotomy. To analyze the windlass mechanism we record two different measurements; the isolated first metatarsophalangeal joint (MTPJ) dorsiflexion angle (IDA) and dynamic plantarization of the first metatarsal head when performing first MTPJ dorsiflexion imprinting a mark on a modeling foam. RESULTS: A total of 30 patients diagnosed with symptomatic HV were included. In all patients, a change in the IDA angle was evident, being overall statistically significant. About modeling foam imprinted mark, all measurements, in all planes of space, had a clear tendency to increase, which turned out to be statistically significant (p < 0.001). CONCLUSIONS: An altered windlass mechanism may be successfully recovered immediately after hallux valgus deformity surgery. This could be evinced by an indirect measurement analyzing the imprint of the head of the first metatarsal in a modeling foam and the IDA. LEVELS OF EVIDENCE II: None.

Influence of laparoscopic surgery on the outcomes of radical cystectomy within a multimodal rehabilitation protocol.

INTRODUCTION AND OBJECTIVE: The implementation of Enhanced Recover After Surgery (ERAS) multimodal rehabilitation protocols in radical cystectomy has shown to improve outcomes in hospital stay and complications. The aim of this analysis is to evaluate the impact of laparoscopic surgery on radical cystectomy within a multimodal rehabilitation program. MATERIAL AND METHODS: The study was carried out in a third level center between 2011 and 2020 including patients with bladder cancer submitted to radical cystectomy according to an ERAS (Enhanced Recovery After Surgery) protocol and the Spanish Multimodal Rehabilitation Group (GERM) with 20 items to be fulfilled. RESULTS: A total of 250 radical cystectomies were performed throughout the study period, 42.8% by open surgery (OS) and 57.2% by laparoscopic surgery (LS). The groups are comparable in demographic and clinical variables (p > 0.05). Operative time was longer in the LS group (248.4 ±â€¯55.0 vs. 286.2 ±â€¯51.9 min; p < 0.001). However, bleeding was significantly lower in the LS group (417.5 ±â€¯365.7 vs. 877.9 ±â€¯529.7 cc; p < 0.001), as was the need for blood transfusion (33.6% vs. 58.9%; p < 0.001). Postoperative length of stay (11.5 ±â€¯10.5 vs. 20.1 ±â€¯17.2 days; p < 0.001), total and major complications were also significantly lower in this group (LS). The readmission rate was lower in the LS group but not significantly (36.4% vs. 29.4%; p = 0.237). The difference between 90-day mortality in both groups was not statistically significant (2.8% LS vs. 4.3% OS; p = 0.546). The differences were maintained in the multivariate models. CONCLUSIONS: Laparoscopic surgery within a multimodal rehabilitation program increases operative time but significantly decreases intraoperative bleeding, transfusion requirements, postoperative length of stay, and complications.

Clast shape-fabric analysis: A comprehensive and efficient methodology to measure particle-orientation data in solid and loose volcaniclastic deposits.

Fabric analysis is essential for understanding the evolution of volcaniclastic deposits. Here we present a comprehensive and efficient methodology, called "Clast shape-fabric analysis," which is part of the Quantitative Textural Analysis (QTA). This methodology combines high-resolution image analysis techniques with geospatial data processing tools. The fabric of a deposit refers to the three-dimensional orientation of the particles with respect to space, where the degree of iso-orientation of the major axes of the particles is taken into account. The process begins with the collection of oriented samples in the field. Then, in the laboratory, the samples are processed to obtain high-resolution images. The final stage involves the analysis of these images using the FabricS program, which combines image processing techniques and circular statistics. An application of the method was made at the Joya Honda Maar in Mexico, where shape-fabric analysis was used to identify the emission centers of pyroclastic materials. In summary, the "Clast shape-fabric analysis" is a reliable, low-cost and high-potential methodology that can be applied in several geoscientific disciplines and other areas of scientific research.•New Methodology for shape-fabric analysis is presented.•The methodology involves field work, laboratory work and image analysis.•Identification of particle orientations in volcaniclastic deposits.

Purinergic system in cancer stem cells.

Accumulating evidence supports the idea that cancer stem cells (CSCs) are those with the capacity to initiate tumors, generate phenotypical diversity, sustain growth, confer drug resistance, and orchestrate the spread of tumor cells. It is still controversial whether CSCs originate from normal stem cells residing in the tissue or cancer cells from the tumor bulk that have dedifferentiated to acquire stem-like characteristics. Although CSCs have been pointed out as key drivers in cancer, knowledge regarding their physiology is still blurry; thus, research focusing on CSCs is essential to designing novel and more effective therapeutics. The purinergic system has emerged as an important autocrine-paracrine messenger system with a prominent role at multiple levels of the tumor microenvironment, where it regulates cellular aspects of the tumors themselves and the stromal and immune systems. Recent findings have shown that purinergic signaling also participates in regulating the CSC phenotype. Here, we discuss updated information regarding CSCs in the purinergic system and present evidence supporting the idea that elements of the purinergic system expressed by this subpopulation of the tumor represent attractive pharmacological targets for proposing innovative anti-cancer therapies.

Volatilome Analysis of Soursop Fruits for the Determination of Kairomone Components That Attract the Annonaceae Fruit Weevil (Optatus palmaris Pascoe).

Soursop possesses the largest fruit size of the Annona genus. However, this species is threatened by the Annonaceae fruit weevil (Optatus palmaris), which can cause the destruction of whole soursop fruits. Recently, the potential of semiochemicals for the management of this insect is highlighted, and its aggregation pheromone has been elucidated. This pheromone works well only when mixed with soursop volatiles. Thus, the aim of this research was to determine specific kairomone components to potentiate the aggregation pheromone of this Annonaceae fruit weevil. This task was carried out via volatilome analysis of soursop fruits, which was correlated with the biological activity of the identified volatiles. The GC-MS analysis of aroma collections of mature soursop fruits and flowers, determined using multivariate data analysis, confirmed a volatile differentiation between these organs. The volatile variation between fruits and flowers was reflected in weevils' preference for mature fruits instead of flowers. Moreover, weevils' response to soursop fruits increased with more mature fruits. This was correlated with volatile changes throughout the phenological stages of soursop fruits. The two volatiles most correlated with weevils' attraction were benzothiazole and (E)-ß-caryophyllene. These volatiles only evoked a response when mixed and potentiated the attraction of the aggregation pheromone. Thus, these two volatiles are active kairomone components with the potential for being used in combination with the aggregation pheromone of Annonaceae fruit weevils in field trials.

Immunohistochemical evaluation of fibrin/fibrinogen, d-dimers, and intravascular thrombosis in brains of dogs with meningoencephalitis of unknown origin.

Granulomatous meningoencephalitis (GME) and necrotizing encephalitides (NE) are the most common immune-mediated inflammatory diseases of the central nervous system in dogs. Activation of the fibrinolytic system in multiple sclerosis, a similar immune-mediated disease affecting the central nervous system in humans, seems to be related to disease progression. The aim of this study was to identify fibrin/fibrinogen and D-dimer deposition, as well as presence of intravascular thrombosis (IVT) in brains of dogs with a diagnosis of GME or NE. Immunohistochemical studies using antibodies against fibrin/fibrinogen and D-dimers were performed. Statistical analyses were performed to determine whether there were differences in the presence and location of fibrin/fibrinogen, D-dimers deposits, and IVT between GME and NE. Samples from sixty-four dogs were included in the study: 32 with a diagnosis of GME and 32 with a diagnosis of NE. Fibrin/fibrinogen depositions were detected in all samples and d-dimers were detected in 43/64 samples. IVT was present in 29/64 samples, with a significantly higher score in samples from dogs with NE than in samples from dogs with GME (P = 0.001). These data support hemostatic system activation in both diseases, especially NE. This finding might be related to the origin of the necrotic lesions seen in NE, which could represent chronic ischemic lesions. Further studies are needed to investigate the association between vascular lesions and the histopathological differences between GME and NE and the hemostatic system as a potential therapeutic target.

Effects of different obesogenic diets on joint integrity, inflammation and intermediate monocyte levels in a rat groove model of osteoarthritis.

Introduction: Obesogenic diets aggravate osteoarthritis (OA) by inducing low-grade systemic inflammation, and diet composition may affect OA severity. Here, we investigated the effect of diet on joint damage and inflammation in an OA rat model. Methods: Wistar-Han rats (n = 24) were fed a chow, a high-fat (HF) diet, or a high-fat/high-sucrose (HFS) for 24 weeks. OA was induced unilaterally 12 weeks after the diet onset by groove surgery, and compared to sham surgery or no surgical intervention (contralateral limb). Knee OA severity was determined by OARSI histopathology scoring system. At several timepoints monocyte populations were measured using flow cytometry, and joint macrophage response was determined via CD68 immunohistochemistry staining. Results: Groove surgery combined with HF or HFS diet resulted in higher OARSI scores, and both HF and HFS diet showed increased circulating intermediate monocytes compared to chow fed rats. Additionally, in the HFS group, minimal damage by sham surgery resulted in an increased OARSI score. HFS diet resulted in the largest metabolic dysregulation, synovial inflammation and increased CD68 staining in tibia epiphysis bone marrow. Conclusion: Obesogenic diets resulted in aggravated OA development, even with very minimal joint damage when combined with the sucrose/fat-rich diet. We hypothesize that diet-induced low-grade inflammation primes monocytes and macrophages in the blood, bone marrow, and synovium, resulting in joint damage when triggered by groove OA inducing surgery. When the metabolic dysregulation is larger, as observed here for the HFS diet, the surgical trigger required to induce joint damage may be smaller, or even redundant.

Congenital mature orbital teratoma: A case report.

Teratomas are gonadal or extragonadal neoplasms, derived from the three embryonic tissues, composed of germ cells of the neuroectoderm, mesoderm and ectoderm. Congenital orbital teratoma (OCT) commonly affects the left orbit, primarily affecting women over men at a ratio of 2:1. We present the case of a female patient of 9 days of extrauterine life with a left mature congenital orbital teratoma. The orbit and oculoplastic service performed an orbital exenteration and total resection of the tumor mass.

Trap-Assisted Complexes in Cold Atom-Ion Collisions.

We theoretically investigate the trap-assisted formation of complexes in atom-ion collisions and their impact on the stability of the trapped ion. The time-dependent potential of the Paul trap facilitates the formation of temporary complexes by reducing the energy of the atom, which gets temporarily stuck in the atom-ion potential. As a result, those complexes significantly impact termolecular reactions leading to molecular ion formation via three-body recombination. We find that complex formation is more pronounced in systems with heavy atoms, but the mass has no influence on the lifetime of the transient state. Instead, the complex formation rate strongly depends on the amplitude of the ion's micromotion. We also show that complex formation persists even in the case of a time-independent harmonic trap. In this case, we find higher formation rates and longer lifetimes than in Paul traps, indicating that the atom-ion complex plays an essential role in atom-ion mixtures in optical traps.

Midbrain and pons MRI shape analysis and its clinical and CSF correlates in degenerative parkinsonisms: a pilot study.

OBJECTIVES: To conduct brainstem MRI shape analysis across neurodegenerative parkinsonisms and control subjects (CS), along with its association with clinical and cerebrospinal fluid (CSF) correlates. METHODOLOGY: We collected demographic and clinical variables, performed planimetric and shape MRI analyses, and determined CSF neurofilament-light chain (NfL) levels in 84 participants: 11 CS, 12 with Parkinson's disease (PD), 26 with multiple system atrophy (MSA), 21 with progressive supranuclear palsy (PSP), and 14 with corticobasal degeneration (CBD). RESULTS: MSA featured the most extensive and significant brainstem shape narrowing (that is, atrophy), mostly in the pons. CBD presented local atrophy in several small areas in the pons and midbrain compared to PD and CS. PSP presented local atrophy in small areas in the posterior and upper midbrain as well as the rostral pons compared to MSA. Our findings of planimetric MRI measurements and CSF NfL levels replicated those from previous literature. Brainstem shape atrophy correlated with worse motor state in all parkinsonisms and with higher NfL levels in MSA, PSP, and PD. CONCLUSION: Atypical parkinsonisms present different brainstem shape patterns which correlate with clinical severity and neuronal degeneration. In MSA, shape analysis could be further explored as a potential diagnostic biomarker. By contrast, shape analysis appears to have a rather limited discriminant value in PSP. KEY POINTS: • Atypical parkinsonisms present different brainstem shape patterns. • Shape patterns correlate with clinical severity and neuronal degeneration. • In MSA, shape analysis could be further explored as a potential diagnostic biomarker.

The chemistry of AlF and CaF production in buffer gas sources.

In this work, we explore the role of chemical reactions on the properties of buffer gas cooled molecular beams. In particular, we focus on scenarios relevant to the formation of AlF and CaF via chemical reactions between the Ca and Al atoms ablated from a solid target in an atmosphere of a fluorine-containing gas, in this case, SF6 and NF3. Reactions are studied following an ab initio molecular dynamics approach, and the results are rationalized following a tree-shaped reaction model based on Bayesian inference. We find that NF3 reacts more efficiently with hot metal atoms to form monofluoride molecules than SF6. In addition, when using NF3, the reaction products have lower kinetic energy, requiring fewer collisions to thermalize with the cryogenic helium. Furthermore, we find that the reaction probability for AlF formation is much higher than for CaF across a broad range of kinetic temperatures.

Considerations for Radiation Safety Professionals to Prepare and Respond to the Next Pandemic.

ABSTRACT: The Health Physics Society's stated mission is "excellence in the science and practice of radiation safety." Why, then, should we discuss disease outbreaks, epidemics, and pandemics with radiation safety professionals? The answer is simple: all workers are impacted by infectious diseases-and, as safety professionals, we will inevitably be called upon to prepare for and respond to these events. The COVID-19 pandemic has disrupted every facet of life, including home, school, work, and leisure. Moreover, virtually all radiation safety professionals have been impacted by the pandemic either personally, academically, or professionally. Even if radiation safety professionals were not involved directly with COVID-19 response, they were impacted by school closures, remote schooling and work, testing regimes, temperature screenings, vaccination programs, and so forth. However, many radiation safety professionals have been intimately involved in COVID-19 response through activities such as the deployment of personal protective equipment, directional airflow verification for isolation areas, disinfection and decontamination efforts, the design and layout of testing and vaccine centers, and in many other ways. Yet, it is likely that many radiation safety professionals have not received formal training in epidemiology, disease control, or other related topics, and thus may not be attuned to the key aspects to consider when the next pandemic emerges-and it will.

The impact of COVID-19 upon student radiographers and clinical training in Latin America.

INTRODUCTION: This study aimed to identify the impact of the COVID-19 pandemic upon radiography education across Latin American countries. METHODS: A survey containing 20 questions was circulated to radiography students, across 13 universities in 11 countries of Latin America using Google Forms. The survey contained open and closed questions. Answers were analysed with descriptive statistics and the methodology of interpretative phenomenological analysis for the open answers. RESULTS: Of the 1310 responses only 23.9% (n = 313) of students reported attending clinical placements and from this cohort only 8.9% (n = 28) became infected with COVID-19. In response to how the pandemic had impacted upon the students' academic progression, the most common topic in the open answers was "Concerns about the lack of clinical training", mentioned by 629 students. Students in middle and later years of their radiography education expressed the greatest concern about future clinical placements. Almost all radiography students (95.2%/n = 1247) indicated that their main concerns regarding COVID-19 infection while undertaking clinical placements was in relation to the risk of infecting their families as most students stated they cohabited with relatives (86.6%/n = 1134). CONCLUSION: Compared to European findings co-habitation trends increased anxiety related to infection and impacted their mental health. Students expressed concern about the quality of education they were receiving during the pandemic and access to resources to facilitate on-line learning was inadequate. Socio-economic and internet connectivity factors specific to Latin America were identified and these issues need to be addressed if on-line education is required in the future. IMPLICATIONS FOR PRACTICE: The COVID-19 pandemic has impacted Latin America and this study identifies the implications for radiography students related to their clinical and academic training and highlights factors which require consideration to support radiography students as the pandemic continues.

Spectroscopic characterization of the a3Π state of aluminum monofluoride.

Spectroscopic studies of aluminum monofluoride (AlF) have revealed its highly favorable properties for direct laser cooling. All Q lines of the strong A1Π â† X1Σ+ transition around 227 nm are rotationally closed and thereby suitable for the main cooling cycle. The same holds for the narrow, spin-forbidden a3Π â† X1Σ+ transition around 367 nm, which has a recoil limit in the µK range. We here report on the spectroscopic characterization of the lowest rotational levels in the a3Π state of AlF for v = 0-8 using a jet-cooled, pulsed molecular beam. An accidental AC Stark shift is observed on the a3Π0, v = 4 ← X1Σ+, v = 4 band. By using time-delayed ionization for state-selective detection of the molecules in the metastable a3Π state at different points along the molecular beam, the radiative lifetime of the a3Π1, v = 0, J = 1 level is experimentally determined as τ = 1.89 ± 0.15 ms. A laser/radio frequency multiple resonance ionization scheme is employed to determine the hyperfine splittings in the a3Π1, v = 5 level. The experimentally derived hyperfine parameters are compared to the outcome of quantum chemistry calculations. A spectral line with a width of 1.27 kHz is recorded between hyperfine levels in the a3Π, v = 0 state. These measurements benchmark the electronic potential of the a3Π state and yield accurate values for the photon scattering rate and for the elements of the Franck-Condon matrix of the a3Π-X1Σ+ system.

Pelvic and inguinal single-site approach: PISA technique. New minimally invasive technique for lymph node dissection in penile cancer.

OBJECTIVES: To describe our initial experience with a new minimally invasive inguinal and pelvic single-access laparoscopic approach, for performing lymph node dissection (LND) in penile cancer: the Pelvic and Inguinal Single Access (PISA) technique. MATERIAL AND METHODS: 10 patients with different penile squamous cell carcinoma stages (cN0 and ≥pT1G3 or cN1/cN2) were operated by means of the PISA technique, between 2015-2018. Intraoperative frozen section analysis was carried out routinely and if ≥2 inguinal nodes (pN2) or extracapsular nodal extension (pN3) are detected, ipsilateral pelvic LND was performed sequentially as a single-stage procedure and using the same surgical incisions. VARIABLES: 30-day PCs, estimated blood loss (EBL), transfusion rate, operative time, time to drainage removal, and length of hospital stay (LOS). Medians and ranges of values for selected variables were reported as descriptive statistics. RESULTS: Inguinal LND was bilateral in all cases, and pelvic LND was required in 40%. Total operative time was 120-170 min and median EBL was 66 (30-100) cc. No blood transfusion was required. No intraoperative complications were noted, and postoperative complications rate was 40% (10% major complications-symptomatic inguinal lymphocele). Median LOS was 5.8 (3-10) days. Median time to inguinal drain removal was 4.7 days. Mean number of lymph nodes removed by inguinal LND: 10.25 (8-14). Limited volume retrospective experience from a referral center with short follow-up. Outcomes reported may not be reproducible by surgeons with less experience and skills. CONCLUSIONS: PISA is a novel, minimally invasive single-site surgical approach to one stage bilateral inguinal/pelvic LNDs for penile cancer showing a low rate of major complications.

The Trend in Costs of Tertiary-Level Neonatal Intensive Care for Neonates Born Preterm at 220/7-286/7 Weeks of Gestation from 2010 to 2019 in Canada.

OBJECTIVE: To describe the trend in costs over 10 years for tertiary-level neonatal care of infants born 220/7-286/7 weeks of gestation during an ongoing Canadian national quality improvement project. STUDY DESIGN: Clinical characteristics, outcomes, and third-party payor costs for the tertiary neonatal care of infants born 220/7-286/7 weeks of gestation between the years 2010 and 2019 were analyzed from the Canadian Neonatal Network database. Costs were estimated using resource use data from the Canadian Neonatal Network and cost inputs from hospitals, physician billing, and administrative databases in Ontario, Canada. Cost estimates were adjusted to 2017 Canadian dollars (CAD). A generalized linear mixed-effects model with gamma regression was used to estimate trends in costs. RESULTS: Between 2010 and 2019, the number of infants born <24 weeks of gestation increased from 4.4% to 7.7%. The average length of stay increased from 68 days to 75 days. Unadjusted average ± SD total costs per neonate were $120 717 ± $93 062 CAD in 2010 and $132 774 ± $93 161 CAD in 2019. After adjustment for year, center, and gestation, total costs and length of stay increased significantly, by $13 612 CAD (P < .01) and 8.1 days (P < .01) over 10 years, respectively; whereas costs accounting for LOS remained stable. CONCLUSIONS: The total costs and length of stay for infants 220/7-286/7 weeks of gestation have increased over the past decade in Canada during an ongoing national quality improvement initiative; however, there was an increase in the number and survival of neonates at the age of periviability.

Observation of Chemical Reactions between a Trapped Ion and Ultracold Feshbach Dimers.

We measure chemical reactions between a single trapped ^{174}Yb^{+} ion and ultracold Li_{2} dimers. This produces LiYb^{+} molecular ions that we detect via mass spectrometry. We explain the reaction rates by modeling the dimer density as a function of the magnetic field and obtain excellent agreement when we assume the reaction to follow the Langevin rate. Our results present a novel approach towards the creation of cold molecular ions and point to the exploration of ultracold chemistry in ion molecule collisions. What is more, with a detection sensitivity below molecule densities of 10^{14} m^{-3}, we provide a new method to detect low-density molecular gases.

Homogenizing the Teaching of Engaged Medical Examinations to Large Numbers of Students: the Experience of the Digital Rectal Examination.

This project aims to complement and homogenise the teaching of indications and technique of digital rectal examination (DRE) through the use of simulators, and subsequently analysed the level of satisfaction with the training and skills acquired. The students were distributed into small groups. One of the workshop's coordinators synthesised indications and procedures of DRE. A teaching video was made with all the contents and was distributed between the trainers. During the workshop, trainers explained the indications and the method of performing the DRE. Then, the selected clinical cases were presented, followed by the DRE by specific simulators. Once the students had completed each exploration, the trainers explained each case and discussed it with students. The following week, an anonymous questionnaire was given to participants to evaluate the workshop. Of the 232 participating students, 53 (23%) responded to the questionnaire. The overall level of satisfaction was higher than 98% (score 4-5), reaching 100% in the evaluation of the practical contents, and 93% of the students would recommend the continuity of the workshop in the next courses. The DRE workshop was well received among medical students, with a high degree of voluntary participation and response rate to the subsequent survey. With this project, we have achieved a greater homogenisation of teaching within the subject of Urology, and greater confidence for the students when facing their future clinical practice.

Determination of the temperature causing a nociceptive response in the tail of albino BALB/c mice.

INTRODUCTION: Designs for determining nociceptive response in rodents are of great use in neurology and experimental neuroscience. Immersing mice's tails in warm water is one of the most widely used procedures to evaluate this response; however, a wide range of temperatures are used in different studies. Knowing the temperature that produces a powerful nociceptive response in the tail of BALB/c mice is extremely useful. METHODS: Eight 2-month-old male BALB/c mice were used. A 14-cm high beaker was filled with water up to 13cm. The animals' tails were immersed in the container with a starting temperature of 36°C. The water temperature was raised in 1°C increments until we identified the temperatures that produced nociceptive responses. That response was determined by counting the time taken before the mouse shook its tail to remove it from the water. RESULTS: Six of the 8 mice began shaking their tails at the temperature of 51°C. All animals removed their tails from the water at the temperatures of 54°C, 55°C, and 56°C, taking a mean time of 8.54, 7.99, and 5.33seconds, respectively. ANOVA applied to the response times for each of the 3 temperatures indicated revealed a value of F=2.8 (P=.123). CONCLUSIONS: The response time was statistically similar for the temperatures of 54°C, 55°C, and 56°C; however, the data were less dispersed for the latter temperature.