Inflammatory, hemostatic, and clinical changes in a baboon experimental model for heatstroke

2005 ◽  
Vol 98 (2) ◽  
pp. 697-705 ◽  
Author(s):  
A. Bouchama ◽  
G. Roberts ◽  
F. Al Mohanna ◽  
R. El-Sayed ◽  
B. Lach ◽  
...  
Keyword(s):  
Heat Stress ◽  
Rectal Temperature ◽  
Tissue Injury ◽  
Systolic Arterial Pressure ◽  
Lactic Dehydrogenase ◽  
Papio Hamadryas ◽  
Control Group ◽  
Improve Outcome ◽  
Baboon Model ◽  
Neurological Morbidity

The mortality and neurological morbidity in heatstroke have been attributed to the host's inflammatory and hemostatic responses to heat stress, suggesting that immunomodulation may improve outcome. We postulated that an experimental baboon model of heatstroke will reproduce human responses and clinical outcome to allow testing of new therapeutic strategies. Eight anesthetized juvenile baboons ( Papio hamadryas) were subjected to heat stress in an incubator maintained at 44–47°C until rectal temperature attained 42.5°C (moderate heatstroke; n = 4) or systolic arterial pressure fell to <90 mmHg (severe heatstroke; n = 4) and were allowed to recover at room temperature. Four sham-heated animals served as a control group. Rectal temperature at the end of heat stress was 42.5 ± 0.0 and 43.3 ± 0.1°C, respectively. All heat-stressed animals had systemic inflammation and activated coagulation, indicated by increased plasma IL-6, prothrombin time, activated partial thromboplastin time, and D-dimer levels, and decreased platelet count. Biochemical markers and/or histology evidenced cellular injury/dysfunction: plasma levels of thrombomodulin, creatinine, creatine kinase, lactic dehydrogenase, and alanine aminotransferase were increased, and varying degrees of tissue damage were present in liver, brain, and gut. No baboon with severe heatstroke survived. Neurological morbidity but no mortality was observed in baboons with moderate heatstroke. Nonsurvivors displayed significantly greater coagulopathy, inflammatory activity, and tissue injury than survivors. Sham-heated animals had an uneventful course. Heat stress elicited distinct patterns of inflammatory and hemostatic responses associated with outcome. The baboon model of heatstroke appears suitable for testing whether immunomodulation of the host's responses can improve outcome.

Analysis of the Inflammatory and Hemostatic Changes and Their Relation to Outcomes in an Experimental Model of Heatstroke in Baboons.

Blood ◽  
2004 ◽  
Vol 104 (11) ◽  
pp. 1033-1033
Author(s):  
George Roberts ◽  
Veronique Olliver ◽  
Sylvie Chollet-Martin ◽  
Fallah Al-Mohanna ◽  
Rafat El-Sayed ◽  
...  
Keyword(s):  
Heat Stress ◽  
Endothelial Cell ◽  
Plasminogen Activator ◽  
Rectal Temperature ◽  
Protein C ◽  
Room Temperature ◽  
Papio Hamadryas ◽  
Control Group ◽  
Improve Outcome ◽  
Baboon Model

Abstract The mortality and neurologic morbidity in heatstroke have been attributed to the host inflammatory and hemostatic responses to heat stress, with the corollary that immunomodulating them may improve outcome. We aimed to examine whether an experimental baboon model of heatstroke will reproduce these responses and clinical outcomes similar to that in humans, thereby providing a model for testing new therapeutic strategies. Eight anesthetized juvenile baboons (Papio hamadryas) were subjected to heat stress in an incubator where the environmental temperature was maintained at 44.2±1.5°C until rectal temperature attained 42.5°C (moderate heatstroke; n=4) or systolic arterial pressure fell to &lt; 90 mmHg, (severe heatstroke; n=4). Animals were then allowed to recover at room temperature. Four sham-heated baboons served as a control group. Plasma IL-6, global coagulation tests and molecular markers of coagulation and fibrinolysis as well as endothelial cell activation/injury were determined at baseline, end of heat exposure or onset of heatstroke (T+0), then at T+1, +2, +3, +12, and +36 hours. The rectal temperature at the end of heat stress was 42.5±0.0 and 43.3±0.2°C for moderate and severe heatstroke respectively. All heat stressed animals had systemic inflammation, and activation of coagulation at onset of heatstroke, indicated by increased plasma IL-6 (345±67 vs 280±130 vs 24±15pg/ml, mean ± SD for severe, moderate and control group respectively, ANOVA-repeated measurements; p&lt;0.001) and thrombin-antithrombin complexes (TAT) levels, 48 ±21 vs 13± 5 vs 6.6±0.9 ng/ml; p&lt;0.01). Tissue factor pathway inhibitor (TFPI) levels were significantly elevated and protein C was decreased but this was not statistically significant. Early activation of fibrinolysis was evidenced by significantly increased D-dimer and tissue plasminogen activator (tPA) levels. Plasminogen activator inhibitor (PAI) was undetectable at onset of heatstroke and at anytime thereafter. No evidence of early endothelial cell injury/activation, as assessed by soluble thrombomodulin (TM), was noted. No baboons with severe heatstroke survived. Neurological morbidity, but no mortality was observed in animals with moderate heatstroke. During passive cooling at room temperature (T+0 to T+3hr), non-surviving animals displayed a different pattern, with significantly greater coagulopathy (peak or nadir levels of TAT, TFPI, and Protein C were 493±66 vs 18±8.6 ng/ml, 64±44 vs 7.2±3.2 ng/ml and 23±11 vs 62±8%), inflammatory activity (IL6, 1770±466 vs 320±76 pg/ml) and endothelial injury (TM, 46±16 vs 9.2±3.2ng/ml) than survivors. Sham heated animals had an uneventful course. These data show that heat stress elicits different patterns of inflammatory and hemostatic responses that were associated with outcome. Additionally, the data suggests that experimental baboon model of heatstroke is suitable for testing whether immunomodulation of the host responses can improve outcome.

scholarly journals Infrared thermography to assess thermoregulatory reactions of buffaloes supplemented with antioxidant and dense energy source in summer season

2021 ◽  
Vol 23 (3) ◽  
pp. 243-248
Author(s):  
YALLAPPA M. SOMAGOND ◽  
S. V. SINGH ◽  
ADITYA DESHPANDE ◽  
PARVENDER SHEORAN ◽  
V. P. CHAHAL
Keyword(s):  
Heat Stress ◽  
Body Temperature ◽  
Infrared Thermography ◽  
Rectal Temperature ◽  
Control Group ◽  
Group I ◽  
Close Relationship ◽  
Region Temperature ◽  
Cortisol Levels ◽  
Lower Magnitude

Twenty-four lactating buffaloes were chosen and subsequently divided into 4 groups i.e. group-I (control), group-II (supplemented astaxanthin at 0.25 mg kg-1 BW/day), group-III (prill fat at 100 g day-1), and group-IV (combination). Surface body temperature at different anatomical regions of buffaloes was recorded using infrared thermography (IRT), rectal temperature using a digital thermometer, and cortisol hormone by ELISA kit at the fortnightly interval. Forehead region temperature showed a higher correlation (0.390) with THI compared to other anatomical regions. The change in surface body temperature was positively correlated with THI and cortisol levels. The increase in the IRT temperature at different anatomical sites of buffaloes was at a lower magnitude in treatment groups compared to the control group. Udder surface temperature was higher in peak lactation and high producing buffaloes. Forehead region temperature showed a close relationship with rectal temperature and cortisol levels of buffaloes. According to the research findings, astaxanthin and prill fat can be used in ameliorating heat stress. Infrared thermography (non-invasive method) of the forehead and udder can be used as indicators for measuring the heat stress and production levels of buffaloes, respectively.

scholarly journals Effect of Saccharomyces boulardii Supplementation on Performance and Physiological Traits of Holstein Calves under Heat Stress Conditions

Animals ◽  
2019 ◽  
Vol 9 (8) ◽  
pp. 510 ◽  
Author(s):  
Lee ◽  
Kacem ◽  
Kim ◽  
Peng ◽  
Kim ◽  
...  
Keyword(s):  
Heart Rate ◽  
Heat Stress ◽  
Cortisol Level ◽  
Water Consumption ◽  
Rectal Temperature ◽  
Saccharomyces Boulardii ◽  
Feed Additive ◽  
Control Group ◽  
Holstein Calves ◽  
Linear Effects

The objective of this study was to determine the effects of Saccharomyces boulardii CNCM I-1079 (SB) as a feed additive on performance, diarrhea frequency, rectal temperature, heart rate, water consumption, cortisol level, and fecal bacteria population in Holstein calves (28 ± 1.6 days of age, body weight of 45.6 ± 1.44 kg, n = 16) under thermal neutral (TN) and heat stress (HS) conditions. During the TN period for 21 days (d 1 to 21), calves receiving SB showed quadratic or linear effects compared to the control group, showing higher dry matter intake (DMI, p = 0.002), and water consumption (p = 0.007) but lower frequency of fecal diarrhea (p = 0.008), rectal temperature (p < 0.001), heart rate (p < 0.001), and fecal microbiota at 21 day (Escherichia coli, p = 0.025; Enterobacteriaceae, p = 0.041). Meanwhile, calves exposed to HS for 7 days (d 22 to 28) receiving SB showed quadratic or linear effects compared to the control group, showing higher DMI (p = 0.002) but lower water consumption (p = 0.023), rectal temperature (p = 0.026), and cortisol level (p = 0.014). Our results suggest that live SB is useful in the livestock industry as an alternative to conventional medication (especially in times of suspected health problems) that can be added to milk replacer for young dairy calves experiencing HS.

scholarly journals Mitigating heat stress of dairy cows bred in a free-stall barn by sprinkler systems coupled with forced ventilation

2017 ◽  
Vol 48 ◽  
Author(s):  
Alessandro D'Emilio ◽  
Simona M.C. Porto ◽  
Giovanni Cascone ◽  
Marco Bella ◽  
Marco Gulino
Keyword(s):  
Heat Stress ◽  
Treatment Group ◽  
Dairy Cows ◽  
Respiration Rate ◽  
Rectal Temperature ◽  
Sprinkler System ◽  
Climatic Conditions ◽  
Control Group ◽  
Forced Ventilation ◽  
Cooling Systems

This paper presents the results of a research study which had the objective of investigating the effect of a sprinkler system coupled with forced ventilation on the heat stress of dairy cows bred in a free stall barn without paddock. To this aim, an experiment was carried out inside a free-stall dairy house equipped with two different cooling systems: a fogging system associated with forced ventilation in the resting area and a sprinkler system associated with forced ventilation in the feeding alley. The experiment regarded two adjacent pens of the barn and was constituted by three different trials carried out in the following periods: 27th June – 7th July (P1), 25th July – 4th August (P2), 24th August – 3rd September (P3). The experimental protocol of each trial required that the treatment group was housed in one pen where the two cooling systems were always activated following an established timetable, whereas the control group was housed in the other pen, where the sprinkler system associated with forced ventilation was always deactivated. Climatic parameters were measured inside each pen of the barn and outside. Then, thermal humidity index (THI) was calculated. Rectal temperature and respiration rate of a sample of dairy cows were monitored each day during the three periods considered (P1, P2 and P3). During the three trials the cows of both groups were subjected to climatic conditions that resulted in average daily THI values between 72.8 and 74.7, corresponding to mild or moderate heat stress. However, during daytime, air temperature and relative humidity reached values corresponding to a severe heat stress, as attested by the maximum THI values that were higher than or very close to 80. Furthermore, it was observed that the sprinklers do not influence the microclimatic conditions. However, the physiological parameters values of the treatment group were always significantly lower than the corresponding ones of the control group. Specifically, the system especially influenced the respiration rate that, in the treatment group, was close to 50 breath/min, while in the control group it reached 70 breath/min. The sprinkler system had more limited effects on rectal temperature that, however, in the treatment group was significantly lower than in the control group (38.7°C to 38.8°C vs 39.1°C 39.4°C) in all the three periods of the experiment. These results show that the sprinkler system could be useful to mitigate heat stress in dairy cows.

scholarly journals PO-251 Aerobic physical training in cool environment protects rat brain against oxidative damage during rest and exercise in heat through the increased expression level of HSP70

2018 ◽  
Vol 1 (5) ◽  
Author(s):  
Dalei Wang
Keyword(s):  
Heat Stress ◽  
Motor Cortex ◽  
Oxidative Damage ◽  
Rat Brain ◽  
Rectal Temperature ◽  
Physical Training ◽  
Heat Exposure ◽  
Exhaustive Exercise ◽  
Control Group ◽  
Cool Environment

Objective The purpose of the study was to explore the mechanism underlying physical training in cool environment (20˚C) improving tolerance to exercise-heat stress. Methods Rats were randomly divided into aerobic exercise group(AE group) and control group (C group). Rats of AE group undertook 5 weeks aerobic physical training in cool environment, rats of C group were kept sedentary. Through Western blotting method, the expression of HSP70 in rats motor cortex of both groups was detected. The hydroxyl radical scavenging capacity (HRSC), malondialdehyde (MDA), superoxide dismutase (SOD) activity, xanthine oxidase (XOD) and glutathion peroxidase (GPX) in rat motor cortex were detected immediately after 1h heat exposure or exhaustive exercise in heat (38-40 ˚C). The exhaustion time and changes of rectal temperature during exhaustive exercise were recorded. Results Results showed that, the HSP70 expression of AE group is higher than C group (P<0.05). After 1h heat exposure or exhaustive exercise, the XOD and MDA of AE group are all lower than C group (P<0.05). The HRSC, SOD and GSH-PX of AE group are all higher than C group (P<0.05). At 30, 45 and 60 min time point, the rectal temperature of AE group are all lower than C group (P<0.05). The exhaustion time of AE group is higher than C group(P<0.05). Conclusions Our results suggest that the enhanced expression of HSP70 and the decreased rise rate of core temperature, may result in the lower oxidative damage in rat brain, this may be one important factor for physical training in cool environment improving tolerance to exercise-heat stress.  

scholarly journals Effects of cooled floor pads combined with chilled drinking water on behavior and performance of lactating sows under heat stress

2021 ◽  
Vol 99 (3) ◽  
Author(s):  
Y Zhu ◽  
L J Johnston ◽  
M H Reese ◽  
E S Buchanan ◽  
J E Tallaksen ◽  
...  
Keyword(s):  
Drinking Water ◽  
Heat Stress ◽  
Respiration Rate ◽  
Rectal Temperature ◽  
Time Budget ◽  
Video Recording ◽  
Lactating Sows ◽  
Before And After ◽  
And Performance ◽  
Drinking Frequency

Abstract This study was conducted to evaluate whether cooled floor pads combined with chilled drinking water could alleviate negative impacts of heat stress on lactating sows. Thirty sows (Landrace × Yorkshire, Parity = 1 to 6) were housed in individual farrowing stalls in two rooms with temperatures being controlled at 29.4°C (0700–1900 hours) and 23.9°C (1900–0700 hours). Sows in one room (Cool), but not in the other room (Control) were provided cooled floor pads (21–22°C) and chilled drinking water (13–15°C). Behavior of sows (15 sows/treatment) was video recorded during farrowing, and days 1, 3, 7, 14, and 21 after farrowing. Videos were viewed continuously to register the birth time of each piglet, from which total farrowing duration and birth intervals were calculated. The number of drinking bouts and the duration of each drinking bout were registered for each sow through viewing videos continuously for 2 h (1530–1730 hours) each video-recording day. Postures (lying laterally, lying ventrally, sitting, and standing) were recorded by scanning video recordings at 5-min intervals for 24 h each video-recording day, and time budget for each posture was calculated. Rectal temperature and respiration rate were measured for all sows the day before and after farrowing, and then once weekly. Sow and litter performance was recorded. Data were analyzed using the Glimmix procedure of SAS. The cooling treatment did not affect sow behavior or litter performance. Sows in the Cool room had lower rectal temperature (P = 0.03) and lower respiration rate (P &lt; 0.001), consumed more feed (P = 0.03), tended to have reduced weight loss (P = 0.07), and backfat loss (P = 0.07) during lactation than sows in the Control room. As lactation progressed, sows increased drinking frequency (P &lt; 0.001) and time spent lying ventrally (P &lt; 0.0001), standing (P &lt; 0.001), and sitting (P &lt; 0.0001), and decreased time spent lying laterally (P &lt; 0.0001) in both Cool and Control rooms. While cooled floor pads combined with chilled drinking water did not affect sow behavior, they did alleviate heat stress partially, as indicated by decreased rectal temperature, respiration rate, weight, and backfat loss, and increased feed intake in lactating sows.

scholarly journals Evaluation of Three Formulations of Essential Oils in Broiler Chickens under Cyclic Heat Stress

Animals ◽  
2021 ◽  
Vol 11 (4) ◽  
pp. 1084
Author(s):  
Jared Ruff ◽  
Guillermo Tellez ◽  
Aaron J. Forga ◽  
Roberto Señas-Cuesta ◽  
Christine N. Vuong ◽  
...  
Keyword(s):  
Heat Stress ◽  
Essential Oils ◽  
Broiler Chickens ◽  
Bone Mineralization ◽  
Body Core Temperature ◽  
Control Group ◽  
Group 4 ◽  
Body Core ◽  
Cyclic Heat ◽  
Group 2

The objective of the present research was to assess the dietary supplementation of three formulations of essential oils (EO) in chickens under heat stress (HS). Day-of-hatch Cobb 500 chicks (n = 500) were randomly distributed into four groups: 1. HS control + control diets; 2. HS + control diets supplemented with 37 ppm EO of Lippia origanoides (LO); 3. HS + control diets supplemented with 45 ppm LO + 45 ppm EO of Rosmarinus officinalis (RO) + 300 ppm red beetroot; 4. HS + 45 ppm LO + 45 ppm RO + 300 ppm natural betaine. Chickens that received the EO showed significant (p < 0.05) improvement on BW, BWG, FI, and FCR compared to control HS chickens. Average body core temperature in group 3 and group 4 was significantly (p < 0.05) reduced compared with the HS control group and group 2. Experimental groups showed a significant reduction in FITC-d at 42 days, a significant increase in SOD at both days but a significant reduction of IFN-γ and IgA compared with HS control (p < 0.05). Bone mineralization was significantly improved by EO treatments (p < 0.05). Together these data suggest that supplemental dietary EO may reduce the harmful effects of HS.

scholarly journals PSV-13 Genetic parameters and quantitative trait loci for heat stress related traits in sheep

2020 ◽  
Vol 98 (Supplement_3) ◽  
pp. 163-164
Author(s):  
Devin R Jacobs ◽  
Claudia E Silvera-Rojas ◽  
Jennifer M Bormann ◽  
Terry A Gipson ◽  
Arthur L Goetsch ◽  
...  
Keyword(s):  
Heat Stress ◽  
Quantitative Trait Loci ◽  
Rectal Temperature ◽  
Quantitative Trait ◽  
Fixed Effects ◽  
Univariate Analysis ◽  
Average Daily Gain ◽  
The United States ◽  
Nucleotide Polymorphisms ◽  
Trait Loci

Abstract Greater selection emphasis has been placed on efficiency than on fitness in livestock populations over the last several decades. Heat stress is a concern in production systems due to the negative effects on production, reproduction, and immunity. The objective of the study was to estimate variance components and identify quantitative trait loci (QTL) for heat stress related traits in sheep. A total of 125 Dorper, Katahdin, and St. Croix ewes originating from four regions of the United States were selected for the experiment. Animals were separated into four trials due to facility limitations. Data were collected for each trial over four consecutive two-week periods in an environmentally controlled facility with targeted heat load index (HLI) for daytime/nighttime of 70/70, 85/77, 90/77, and 95/81. Body weight was collected three times per week and rectal temperature was collected weekly. Black globe temperature and humidity were measured every 15 minutes. Animals were genotyped using the Illumina OvineSNP50 BeadChip. After quality control, 49,396 effective single nucleotide polymorphisms were included in the univariate analysis performed with the BLUPF90 suite of programs. Fixed effects in the models included region of origin, breed, trial, and age as a covariate. Traits analyzed included rectal temperature at 95 HLI (RT95), feed intake at 95 HLI (FI95), and average daily gain for the period for HLI between 90 and 95 (ADG). Heritabilities for RT95, FI95, and ADG were 0.35, 0.10, and 0.10, respectively. Largest effect QTL were identified on chromosomes 23, 9, and 6 for RT95, chromosomes 9, 2, and 20 for FI95, and chromosomes 6, 1, and 5 for ADG. Many of the regions identified have also been associated with weight and carcass traits in other studies, but few had obvious connections to the heat stress related response. In conclusion, results suggest selection could improve heat tolerance in sheep.

scholarly journals Effects of Sprinkler Flow Rate on Physiological, Behavioral and Production Responses of Nili Ravi Buffaloes during Subtropical Summer

Animals ◽  
2021 ◽  
Vol 11 (2) ◽  
pp. 339
Author(s):  
Musa Bah ◽  
Muhammad Afzal Rashid ◽  
Khalid Javed ◽  
Talat Naseer Pasha ◽  
Muhammad Qamer Shahid
Keyword(s):  
Heat Stress ◽  
Milk Yield ◽  
Flow Rate ◽  
Rectal Temperature ◽  
Latin Square ◽  
Flow Rates ◽  
Group Water ◽  
Humidity Index ◽  
Daily Milk Yield ◽  
Daily Milk

Water buffaloes wallow in water to combat heat stress during summer. With the decreasing reservoirs for wallowing, the farmers use sprinklers to cool the buffaloes in Pakistan. These sprinklers use a large quantity of groundwater, which is becoming scarce. The objective of the current study was to determine the effect of different sprinkler flow rates on the physiological, behavioral, and production responses of Nili Ravi buffaloes during summer. Eighteen buffaloes were randomly subjected to three sprinkler flow rate treatments in a double replicated 3 × 3 Latin square design. The flow rates were 0.8, 1.25, and 2.0 L/min. During the study, the average afternoon temperature humidity index was 84.6. The 1.25 and 2.0 L/min groups had significantly lower rectal temperature and respiratory rates than the 0.8 L/min group. Water intake was significantly higher in the 0.8 L/min group. Daily milk yield was higher in the 1.25 and 2.0 L/min groups than in the 0.8 L/min group. These results suggested that the sprinkler flow rates > 0.8 L/min effectively cooled the buffaloes. The sprinkler flow rate of 1.25 L/min appeared to be more efficient, as it used 37.5% less water compared to the 2.0 L/min.

Wetting and the physiological responses of grain-fed cattle in a heated environment

2004 ◽  
Vol 55 (3) ◽  
pp. 253 ◽  
Author(s):  
John B. Gaughan ◽  
M. Shane Davis ◽  
Terry L. Mader
Keyword(s):  
Heat Stress ◽  
Experimental Design ◽  
Rectal Temperature ◽  
Environmental Conditions ◽  
Dry Matter ◽  
Physiological Responses ◽  
Dry Matter Intake ◽  
Metabolic Responses ◽  
Hot Days ◽  
Carry Over

A controlled crossover experimental design was used to determine the effect of altered water sprinkling duration on heifers subjected to heat stress conditions. Heifers were subjected to 3 days of thermoneutral conditions followed by 3 days of hot conditions accompanied by water sprinkling between 1300 and 1500 h (HOT1–3). Then on the following 2 days (HOT4–5), environmental conditions remained similar, but 3 heifers were sprinkled between 1200 and 1600 h (WET) and 3 were not sprinkled (NONWET). This was followed by a 1-day period (HOT6) in which environmental conditions and sprinkling regimen were similar to HOT1–3. Rectal temperature (RT) was collected hourly, and respiration rate (RR) was monitored every 2 h on HOT Days 2, 4, 5, and 6. Dry matter intake and rate of eating were also determined. Sprinkling reduced RR and RT (P < 0.01) of all heifers during HOT1–3. During HOT4–5, WET heifers had lower (P < 0.05) RT than NONWET from 1300 to 700 h and lower RR from 1400 to 2000 h. Dry matter intake of NONWET heifers was reduced by 30.6% (P < 0.05) during HOT4–5 and by 51.2% on HOT6. On HOT4–5 the dry matter intakes of WET heifers were similar to intakes under thermoneutral conditions. During HOT6, RT was again reduced following sprinkling in all heifers. Comparison of RT and RR of NONWET and WET heifers on HOT1–3 v. HOT6 revealed that under similar environmental conditions, NONWET heifers had increased RT, partially due to carry-over from HOT4–5. However, NONWET heifers had 40% lower feed intake but tended to have lower RR on HOT6 v. HOT1–3. Only RR of WET heifers was greater on HOT6, possibly a result of switching from a 4-h back to a 2-h sprinkling period, while maintaining a 62% greater intake (5.80 v. 3.58 kg/day) than NONWET heifers during this time. Results suggest that inconsistent cooling regimens may increase the susceptibility of cattle to heat stress and elicit different physiological and metabolic responses.

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