Of bone and ice

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This content does not have an English version. This content does not have an Arabic version. See more conditions. First aid Fractures broken bones. Sections Basics Resources. Products and services. Thank you for subscribing Our Housecall e-newsletter will keep you up-to-date on the latest health information. Sorry something went wrong with your subscription Please, try again in a couple of minutes Retry.

Show references Marx JA, et al. General principles of orthopedic injuries. Philadelphia, Pa. Accessed Jan. Millman M. Cuts, scrapes and wounds. Rochester, Minn. What to do in a medical emergency: Broken bones. American College of Emergency Physicians. Overview of fractures. Merck Manual Professional Version. Bone anabolism and catabolism are altered in different exercise types, and mechanical or metabolic stimuli ultimately lead to different bone outcomes Proia et al.

For instance, resistance and impact exercise, such as high-impact jumping with enough ground reaction forces GRFs Nguyen, ; Proia et al. The mechanism behind changes in bone metabolism caused by exercise is complex, and the influencing factors include age, sex, nutrition, genetics, training status, and the characteristics of the specific exercise stimulus Dolan et al.

Nevertheless, monitoring of bone re modeling markers e. Despite a broad range of exercise types having been investigated with regard to the response of bone metabolism Vainionpaa et al. Specifically, cold exposure may have synergistic effects when occurring in combination with exercise to cause certain metabolic perturbations, such as adrenergic humoral stimulation and adipose tissue browning Doubt, ; Jett et al. Additionally, cold exposure can also cause changes in bone metabolism and morphology through increasing sympathetic tone and augmenting brown adipose tissue BAT Robbins et al.

It is generally accepted that activation of the sympathetic nervous system SNS by cold stress damages the bone architecture Kajimura et al. Actually, the majority of studies suggest that cold exposure contributes to bone loss by inhibiting osteogenesis and enhancing osteoclastic metabolism Patel et al. In contrast, some data demonstrate a positive association between cold stress and bone metabolism.

For instance, in vitro studies showed that hypothermia could upregulated the key osteoblast transcription factor runt-related transcription factor 2 Runx2 and osterix expression, resulting in the enhancement of osteoblasts bone formation Aisha et al. Similarly, effects of cold exposure on bone repair and bone formation were also observed through in vivo studies Galliera et al. Taking these findings together, both exercise and cold exposure cause bone metabolic responses, but there are currently major gaps in our understanding of the combined effect of them on bone, especially in the dynamic processes in the human body.

IS is the most common cold exercise in cold regions. As such, in the present study, IS was chosen to evaluate the response of bone metabolism to severe cold exercise. The aim of this study is to investigate the variations in circulating bone metabolism markers after IS. To address the study goals, we conducted an observational study. The subjects were IS enthusiasts, not newcomers to the sport, aged over 40 years who volunteered to participate in the study.

The exclusion criteria included: 1 a failure to provide written informed consent; 2 mental illness or an inability to cooperate with the examination; 3 a history of cardiovascular or cerebrovascular diseases, such as myocardial infarction, serious arrhythmia, or stroke; 4 a diagnosis of osteoporosis; 5 the use of anti-osteoporosis drugs, such as bisphosphonates; and 6 any health risks potentially associated with the study. A total of 87 ice swimmers 90 ice swimmers volunteered to participate, however, three participants who failed to complete the study were excluded enrolled in this study.

These 87 individuals were women and men who were recruited from Liaoyang and Shenyang cities, Liaoning Province, in northeast China. The research process was as previously described Mu et al. Briefly, all participants were divided into three groups, and each group performed the exercise session at a different place and on a different day. The three research times were the winter swimming bases of the Liaoyang ice swimmers on January 12, , and in Shenyang on January 26 and February 16, The length of the three study lanes was different, but they were all 25—30 meters.

On the day of the IS, no participants were required to fast, and all underwent the following in sequence: had blood drawn 30 min before IS , performed warm-up preparations onshore, performed IS h, according to their own typical IS schedule; swimming time and distance were not mandated , went ashore to perform exercises to recover the body temperature, and then had blood drawn again 30 min after IS.

These recovery exercises usually included rope skipping, running, and push-ups. It is important to note that IS is a mixed sport including warm up and recovery temperature resistance exercise and swimming. We asked the participants to perform IS according to their own IS distance and time habits on the first day, and reported the distance and time on the questionnaire for the second day.

The swimming speed of each participant was different when they were in cold water; however, most participants reported that they took 2—3 min to swim a circle 50—60 m , and The study protocol was approved by Shengjing Hospital Ethics Committee of China Medical University and written informed consent was obtained from all participants. The participants were barefoot and wore only underclothes during the height and body weight measurements.

Body mass index BMI was calculated as body weight divided by height squared. To reduce the likelihood of error, the same experienced operator performed all scans in accordance with standardized procedures. The coefficient of variation was under 1. The T-score was estimated from the lowest measured BMD value. In accordance with the criteria of the World Health Organization WHO , a T score above —1 was considered normal, a score between —1 and —2.

Detailed questionnaires were completed by all of the participants. The data recorded included age, sex, previous fracture history, history of hip fracture in the parents, current smoking status, administration of adrenocortical hormone, history of rheumatoid arthritis, history of secondary osteoporosis, and alcohol consumption. Blood samples were collected by trained nurses between approximately h and h. The data were analyzed for normality by the Shapiro—Wilk test.

Normally distributed data of continuous variables are presented as mean and standard deviation. Non-normally distributed data of continuous variables are presented as median and first quartile to third quartile. Data of categorical variables are presented as numbers and percentages.

The t -test, Mann—Whitney U test, or chi-squared test was used to evaluate differences in population characteristics between men and women according to the type of variable. The paired samples t -test or the Wilcoxon signed-rank test was used to evaluate differences in serum bone metabolism markers between before and after IS according to the type of variable. P for trend was calculated by entering the median value of each category of osteoporosis as a continuous variable.

Spearman correlation coefficient analysis was performed to determine the correlations among bone metabolism markers, and between bone metabolism markers and bone mass density status variables. Table 1 show the characteristics of the 72 male and 15 female ice swimmers participating in this study. None of the female participants smoked or drank alcohol.

The women had significantly lower spine and femoral neck BMC and BMD, while they had a significantly higher risk of major osteoporotic fracture than men. In all subjects, IS-induced changes in serum bone metabolism markers are reported in Table 2. Table 2. Variations of bone metabolism characteristics responses to ice swimming.

Six 6. One 1. Before IS, the numbers of those with hypophosphatemia, normal blood phosphorus, and hyperphosphatemia were 9 Meanwhile, after IS, no subjects had hypophosphatemia and the number of cases with hyperphosphatemia increased to 5 5. The baseline levels pre-IS and changes of serum bone metabolism markers were grouped according to the osteoporosis criteria, as shown in Table 4 , and Supplementary Tables 3 — 7.

Among the changes of bone metabolism markers, there were no associations between osteoporosis status and the changes of bone metabolism markers in response to IS in the total and male populations Table 4 and Supplementary Table 6. In addition, the correlations of bone metabolism markers with bone status parameters are presented in Supplementary Tables 8 — Table 4.

The differences in bone metabolism characteristics among the normal bone mass, osteopenia, and osteoporosis groups. The correlations of biomarkers among all subjects are presented in Figure 1 and Table 5. Figure 1. In the present study, we chose IS as a representative exercise performed in severe cold to explore the changes of bone metabolism upon cold exercise in humans.

We recruited 87 ice swimmers, making this the largest IS study to have been performed. Finally, there were significant correlations among the bone metabolism markers, suggesting potential links between them. Here, we report that regular IS exercise, involving a warm-up outdoors, 2—3 min of IS, and recovery exercise, could significantly increase PTH levels. In that study, the process of IS was similar to ours, but the subjects spent more time in ice water 10—15 min. Although the evidence is limited, the similar results shown for the different study cohorts indicate that the PTH changes after IS may not be a coincidence and perhaps could be the synergistic effect of exercise and cold stress.

Numerous studies have shown that exercise increases PTH secretion Lombardi et al. However, PTH has also been observed to exhibit a marked increase despite no change or a rise in calcium concentration during exercise Scott et al. Specifically, cold stress could amplify the responses involving the above factors, for instance, catecholamine, during exercise by activating the SNS Kvetnansky et al. The magnitudes of PTH, calcium, and phosphorus changes may have clinical significance.

In this regard, we classified PTH, blood calcium, and phosphorus according to their clinical reference ranges, and found that the proportions of subjects with hyperparathyroidemia and hypercalcemia increased, meanwhile the proportion of subjects with hypophosphatemia decreased and that with hyperphosphatemia increased. Consequently, ice swimmers need to be warned of IS induced hyperparathyroidemia, hypercalcemia, and hyperphosphatemia as potential cardiovascular health risks. In addition, some drugs can affect serum PTH levels, for instance, the osteoporosis drugs bisphosphonate and denosumab increase the PTH level, while teriparatide decreases its level Lombardi et al.

Hence, IS plus bisphosphonate or denosumab may intensify hyperparathyroidism to exacerbate the health risk associated with IS. Bone re modeling markers BMM are products of bone proteins or cells and represent dynamic bone processes involved in bone anabolism and catabolism Dolan et al.

Generally, acute vigorous exercise activates osteoclastic metabolism, while bone anabolism appears to be largely unresponsive to this Dolan et al. In contrast, the evidence on BMM changes due to cold exposure is limited. This is somewhat confusing as, theoretically, PTH is elevated and catecholamines are secreted by SNS activation under cold exercise stress Kvetnansky et al. However, the PTH axis and SNS are intricately related and little is known about the effect of both signal activations on bone metabolism in humans.

However, these hypotheses need to be confirmed. Osteocalcin is a non-collagenous protein mainly synthesized by osteoblasts Hauschka et al. It participates in the regulation of mineralization and is considered as an osteogenic marker Brown et al. We speculate that osteogenic mineralization lags behind bone resorption and that the use of a single sampling point may have led to time-specific changes being missed, impacting on the observed findings.

On the other hand, it is worth noting that osteocalcin plays important extra-skeletal roles, such as in glucose metabolism, fat metabolism, and muscle activity Lee and Karsenty, ; Lombardi et al. Thus, besides bone metabolism, changes in osteocalcin may represent metabolic reactions. However, we did not observe responsiveness to osteocalcin during the short recovery window after regular IS exercise.

The basal bone metabolism levels and changes in bone metabolism markers following IS may be related to bone conditions. In this regard, we investigated the relationship between bone metabolism markers and bone status parameters. This indicates that different bone status, particularly combined with sex differences, can affect the variations in the levels of some bone metabolism markers caused by IS.

These results suggest that age is also an important impact factor in bone response to IS. It is well documented that PTH exerts biphasic effects on skeletal homeostasis, with continuous hyperparathyroidism being catabolic, while intermittent treatment boosts bone formation Wein and Kronenberg, In contrast, some data suggested that cold exposure inhibits bone anabolism and leads to bone loss Patel et al. Simultaneously, our results show a divergence between PTH elevation and a decline in bone turnover.

Thus, the question arises of what outcomes of IS impact on bone health. We attempted to use multivariate analysis to determine the relationships of IS frequency and years with bone status and metabolism parameters. This suggests the skeletal alterations by the IS-induced perturbation of bone metabolic markers are ultimately unclear in the current study, and further research is warranted to answer the above question.

We analyzed the relationship between our body composition data detection method reported previously, Mu et al. This study had several limitations. First, we only investigated bone metabolism markers once after IS, but such single sampling results would fail to capture any dynamic changes of bone metabolism, and would also miss the overall bone remodeling process during the recovery period after IS. Second, we did not correct for plasma volume shifts, which are known to occur during exercise or upon changes in the ambient temperature Kargotich et al.

The present study conducted in a group of ice swimmers showed significant alterations in bone metabolic markers after IS. In particular, PTH showed marked increases after IS, the underlying mechanisms of which may involve variations in physiological factors e. Finally, although the differences in bone conditions may affect the changes of some bone metabolism markers caused by IS, the impact of long-term IS on the skeletal system is still unclear, which needs to be clarified by more strictly controlled, long-term studies that consider age and sex.

Nonetheless, this study expands our understanding of the profile of bone metabolism changes upon cold exercise. The raw data supporting the conclusions of this article will be made available by the authors, without undue reservation. The studies involving human participants were reviewed and approved by Shengjing Hospital Ethics Committee of China Medical University.

SM interpreted the results and wrote the manuscript. All authors have read and approved the final manuscript, and agreed with the order of the presentation of the authors. The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest. All claims expressed in this article are solely those of the authors and do not necessarily represent those of their affiliated organizations, or those of the publisher, the editors and the reviewers.

Any product that may be evaluated in this article, or claim that may be made by its manufacturer, is not guaranteed or endorsed by the publisher. Aisha, M. Short-term moderate hypothermia stimulates alkaline phosphatase activity and osteocalcin expression in osteoblasts by upregulating Runx2 and osterix in vitro.

Cell Res. Barry, D. Acute calcium ingestion attenuates exercise-induced disruption of calcium homeostasis. Sports Exerc. Bauer, D. Boden, S. Calcium homeostasis. North Am. Google Scholar. Bouassida, A. Parathyroid hormone and physical exercise: a brief review. Sports Sci. Brown, E. Calcium, magnesium and the control of PTH secretion. Bone Miner. Brown, J.

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No, it couldn't. She doesn't negotiate with terrorists, she kills them. It's just like she said - she's not him. And to be okay with a living man who thinks her life full of misery was for the greater good, she doesn't want. So she had to get him out of the way, not without a little manipulation on her part.

The kiss was not entirely a scheme of distraction, it was gratitude for those kind and sincere words of understanding on his part, as well as goodbye. She hoped he understood that. Of course, killing didn't bring her any obvious relief, but at least everyone is free and decides their own fate. Loneliness had always been her friend. In the midst of countless apocalypses, it would have been foolish to have developed any kind of attachment when it had always threatened her in every possible way, whether desperately craving one last satisfaction before imminent doom or a distraction from her primary mission.

But it was so strange with Loki, his words of admiration on Lamentis-1 prompted her to feel seen for the first time, as if he saw the real her, not her role as Loki, the villain and deceiver she was supposed to play by TVA rules. The gentle touch of her hand and that look by the lake. She had never had that before. She was scared. What if it was all a hoax? What if the whole thing was a sham just to use her to get to the man behind the curtain and seize power? Isn't that what makes Loki a Loki?

Deception, lies, and manipulation. After a lifetime of running, trusting anyone but herself would be akin to giving a dagger a blade to herself. It's just like he said - love is a dagger. And like a complete fool she did, she fell in love with him. Which made his betrayal hurt more in her chest, where her heart bled. But she was wrong. He was sincere when he said it wasn't about the throne. She could tell by his eyes - they were the mirror of his soul, just like hers.

But she's not a good person, she doesn't deserve the care he wants to give her. All she wants is to fill that aching void in her soul with the death of her tormentor. She needs that. Without it, she will simply fade away. She wakes up with a sob, her side aching where she was last hit by that modified minuteman. She assumed that one of the variants of He Who Remains had already managed to take over the TVA, but her long search for Loki there led nowhere.

When Sylvie opened her eyes, she saw the light of the fire reflecting off the surface of the ice cave. How did she get here? She crouched sharply and found that she was covered by the fur pelt of some unknown beast. What the hell.

Without making a loud sound, she stood up, peering into the darkness of the cave. A blizzard was barely audible howling in the background. Her words were followed by the creaking sound of ice, as if someone, not without undue caution, was rising from the ice. She could not see the figure of the creature in the darkness of the cave, but she could hear it approaching her with creaky steps. Her heart pounded in her chest with fear of the unknown.

Trying to hide the uncertainty in her voice, she says, "I warn you that I know how to fight. Come out with your hands up! From the depths came a voice: "And this is the attitude you give to the owners of the house in which you now find yourself? Despite the warmth of the cave, a cold sweat broke out at the sound of that voice. She knows that voice. It belongs to the man she left behind. But it can't be true, from what she heard from him, being on Jotunheim would be last on his wish list.

It could only be possible with one option. Interrupting her thoughts, a mysterious figure emerged from the shadows. Her soul went to her heels when she saw his face, but only covered in blue and several feet taller than her acquaintance.

It reflected the light of the cave fire, while his red eyes stared at her. Sylvie shrieked in surprise and backed up until her back was against the cool surface of the icy wall. Has the box of the Casket of Ancient Winters been returned to Jotunheim?

She knew little of the thing due to her age, but her father had told her that it had once been a symbol of her people. The heart of its magic. With false confidence, she squared her shoulders and, with a lift of her chin, blurted out: "Well, in that case, I have to go.

Turning to leave the cave, she staggered away. She should stay away from all versions of this idiot, at least for the health of her unhealed heart. But fate often ignores her wishes, she would make sure of that as she approached the exit behind which a veritable blizzard unfolded.

Even in her Jotun form she will not be able to pass this blizzard, visibility is zero. After swallowing a swear word, she goes back inside. Her "new" acquaintance bestows upon her a mocking smile. I thought you were in a hurry to go somewhere," he sits down beside the fire across from her. He corrected: "Saved you, yes," Loki pointed to the pelt that was still on the floor. She raised an eyebrow at him, but still sat down. Showing her vulnerability was not in her nature.

Loki chuckles. This gave me an idea on how to unlock the secrets of the dragons. I stacked up some wood and netherrack into a large pile and placed the largest of the eggs onto it. Once the egg was atop the pile, I lit the pile afire, and the wood and netherrack around the egg burst into flames.

After waiting for around a short time, I could not see any difference with the egg. I thought of removing the egg and looking for another method of hatching the egg, but I remembered that dragons are large beings that require a large amount of energy. Deciding not to be hasty, I let the egg sit on the perpetual fire for three days. My decision was very successful! After taking down one of the more monstrous ice dragons I had found in a cavern, I noticed that the beast was guarding its own clutch of eggs.

These eggs were a multitude of faded colours, all coated with shiny scales. While moving the eggs to a safer location near my home, I noticed that these eggs were much colder than those of a chicken or other bird. I poured some buckets of water into a small pond and placed the largest of the eggs onto it. Once the egg was in the pond, I filled the pond around the egg in order to cool it down. I thought of removing the egg and looking for another method of hatching the egg, but I remembered that dragons are large beings that require a great amount of time to grow.

Deciding not to be hasty, I let the egg sit in the lake for three days. The egg formed ice around itself and in a few days hatched! I am now in possession of a young dragon. Dragon scales are one of the most common items that can be recovered from dead beasts. They can be crafted into suits of armour, which are very durable.

The second most common loot one can receive are dragon bones. Dragon bones are used in many recipes, but are mostly for crafting tools and weapons. These recipes usually involve the use of wither bone instead of sticks. Wither bone can be gathered from black skeletons in the nether. Wither bone can also be made into wither bone shards, which replace flint when making dragon bone arrows. Dragon flesh can also be harvested from dragons. This meat cannot be cooked, and has different effects based on what type of dragon it came from.

The fire dragon flesh will smite its eater, and ice dragon flesh can slow its consumer to a halt. All flesh sates as much as cooked beef. Dragon hearts can only be dropped once by each corpse. I currently am not aware of their purpose. Dragon skulls are also only dropped once from bodies. These large bones are used to make command staffs and can be placed on the ground.

They can also be put onto banners for a dragon shape. Dragon blood, both fire and ice variants, certainly have very magical properties. However, these properties are certainly elusive, and I must research more into them. It seems that now dragon bones and scales can be safely compacted into large cubes for storage. I predict that consolidating such a large mass of magical presence in a block could have unforeseen uses.

The magical aura of dragon bones and dragon scales definitely has some powerful properties, as is well known. When combined with stone, they become indestructible to dragon frost and flame. It appears there are several constructs that can be made with dragonforge bricks. It is also known that there are ice dragon variants as well.

Once you have acquired a dragon forge core, a dragon forge input, 8 dragon bone blocks, and 17 dragon forge bricks, you can construct the dragon forge itself. There are 3 layers. Construct the forge by placing first layer, then a second layer on top of first layer, then a third layer above second layer. Once the forge is complete, it will need some sort of power. This can be achieved either by building the structure close to a tame dragon, or capturing a wild dragon using chains.

Chains can be created to capture wild dragons and any other monster. They can be tied to the walls. Dragons will destroy most walls, like cobblestone walls, so those who wish to power their furnace with a dragon need dragon bone wall.

To properly power a forge, one must place the chained or tame dragon directly in front of the aperture. Then the dragon will begin to breathe flame or frost as long as there are valid items in the forge. Most items, when placed in a forge, will be turned to ash or dragon ice respectively. But placing an iron ingot and dragon blood fire blood for fire forges, ice blood for ice forges will result in a powerful alchemical metal. The result is a metal known as dragonsteel.

Dragonsteel is one of the strongest and most versatile materials known to man. It can be made into tools, armour, and dragon armour. Keep in mind that dragon forges can be constructed with ice dragons in mind, to create Ice dragonsteel using the sheer cold of their frost breath. Fire dragonsteel sets attackers aflame for up to 15 seconds and deals a large amount of knockback.

Ice dragonsteel freezes target into a giant block of ice. Both types of dragonsteel deal high amounts of damage and can easily dispatch a large dragon. Dragonsteel armour also provides increased protection against dragon breath attacks. So the legends are true. Such beasts such as the one this entry focuses on do exist.

Very well. I shall try as well as I can describe such a beast and its activities. The appearance of the beast is obviously reptilian. However, it is much larger than the average reptile; Individuals I have seen range from the size of a pig to 25 blocks! There are even rumours of larger dragons, sleeping in ancient crypts under the earth. Another notable feature they possess is the ability of flight. This is indicated by the development of large wings, used in aviation.

Although the beasts seem sluggish at first, they can lift off and fly swiftly after prey. Perhaps the most dangerous aspect about them is their ability to produce fire from their mouths. They use this power to cook their prey alive.

Male fire dragons have patterned wings and collect more valuable loot, whereas females have curved horns. Simply creating fire is not the only way fire dragons dispatch their prey. They also have many attacks. Younger dragons are less effective in this attack, while larger ones can scorch nearby terrain, inflicting massive amounts of damage. The dragon can also build up a blast of flames into a solidified block.

Only older dragons are capable of this attack. This is the main attack of the fire dragon. It is powerful, and quick, but is not usually instantly deadly. However, the dragon has a rarer melee attack: shaking its prey to death. In this attack, the dragon picks up its target in its mouth, and rapidly shakes it in order to severely injure its prey. The dragon also has a final melee attack, in which it builds up a kinetic force in its tail to slam into its target. This attack is very effective, but it takes a while to build up.

They can also beat their wings to push prey back. Taking down a dragon of any stage is not a very easy task. Since fire dragons use elemental ranged attacks, it would be smart thinking to use protective potions and long range weaponry. If you want to take down one of these beasts, try and avoid flames, and watch for charge up behaviour for many attacks.

Another thing one should note about fire dragons is their different life stages. In the earliest stage, the dragon is unable to spout flames and is limited to biting attacks. Once it is in its second stage, it can breathe weak flames and do mild amounts of damage.

The most notable development of the third stage is the gaining of the fire charge attack, which can deal large amounts of damage. Stage 3 dragons are also the most common type of dragons found in nature. Stage 4 is generally more powerful and cannot be found in roosts. Stage 5 produces a truly terrifying animal. They follow all the other rules of a stage 4 dragon, except much more powerful and deadly. They are incredibly rare, and it is unheard of for a single soul to defeat one. There are even rumours of larger dragons, sleeping in ancient crypts under the ice.

Perhaps the most dangerous aspect about them is their ability to produce ice breath from their mouths. They use this power to freeze their prey alive. Male ice dragons have patterned wings and collect more valuable loot, whereas females have curved horns.

Simply creating ice breath is not the only way ice dragons dispatch their prey. Younger dragons are less effective in this attack, while larger ones can freeze nearby terrain, inflicting massive amounts of damage. The dragon can also build up a blast of ice into a solidified block.

This is the main attack of the ice dragon. Since ice dragons use elemental ranged attacks, it would be smart thinking to use protective potions and long range weaponry. If you want to take down one of these beasts, try and avoid ice blasts, and watch for charge up behaviour for many attacks. Another thing one should note about ice dragons is their different life stages. In the earliest stage, the dragon is unable to spout blasts and is limited to biting attacks.

Once it is in its second stage, it can breathe weak frost and do mild amounts of damage. The most notable development of the third stage is the gaining of the ice charge attack, which can deal large amounts of damage.