AIM:To investigate the stress-induced apoptosis of natural killer(NK)cells and the changes in their killing activity in mouse livers.METHODS:A restraint stress model was established in mice.Flow cytometry was employed...AIM:To investigate the stress-induced apoptosis of natural killer(NK)cells and the changes in their killing activity in mouse livers.METHODS:A restraint stress model was established in mice.Flow cytometry was employed to measure the percentage of NK cells and the changes in their absolute number in mouse liver.The cytotoxicity of hepatic and splenic NK cells was assessed against YAC-1 target cells via a 4 h 51Cr-release assay.RESULTS:The restraint stress stimulation induced the apoptosis of NK cells in the liver and the spleen,which decreased the cell number.The number and percentage of NK cells in the spleen decreased.However,the number of NK cells in the liver decreased,whereas the percentage of NK cells was significantly increased.The apoptosis of NK cells increased gradually with prolonged stress time,and the macrophage-1(Mac-1)+NK cells were more susceptible to apoptosis than Mac-1-NK cells.Large numbers of Mac-1-NK cells in the liver,which are more resistant to stress-induced apoptosis,were observed than the Mac-1-NK cells in the spleen.The stress stimulation diminished the killing activity of NK cells in the spleen was significantly decreased,but the retention of numerous Mac-1-NK cells in the liver maintained the killing ability.CONCLUSION:Significant stress-induced apoptosis was observed among Mac-1+NK cells,but not Mac-1-NK cells in the mouse liver.Stress stimulation markedly decreased the killing activity of NK cells in the spleen but remained unchanged in the liver.展开更多
In a series of our recent studies, stress was found to induce simultaneously hypothermia and hyperglycemia. These conditions are beneficial to obtain prompt force which depends on the glycolysis pathway and to escape ...In a series of our recent studies, stress was found to induce simultaneously hypothermia and hyperglycemia. These conditions are beneficial to obtain prompt force which depends on the glycolysis pathway and to escape emergency. Since we have noticed that such conditions resemble the internal environment seen in some cancer patients, it was investigated whe- ther such conditions were accompanied with other patients. We selected patients with early and advanced cancer. Body temperature and other parameters including blood gas contents were examined. A difference was seen in body temperature, namely, many patients showed hypothermia, irrespective of cancer stages. Fur- ther characterization of other parameters show- ed that hypothermia and hyperglycemia existed in many patients. They had immunosuppressive state and anemia. Blood gas analysis showed that oxygen contents were low and carbon dioxide contents were high in patients. These results suggest a possibility that the internal environment seen in patients is responsible to induce onset of disease and to maintain their cell growth, because cancer cells have an energy system of predominant glycolysis. Although hypothermia, hypoxia and hyperglycemia are important to activate the glycolysis pathway and to escape from emergency, such responses suppress the mitochondrial pathway for long span and may result in carcinogenesis.展开更多
The di-zhen (DZ) is an ancient type of acupuncture needle with a history dating back more than 2000 years. Unlike modern acupuncture needles, the DZ is not inserted subcutaneously, and is safely and commonly used at t...The di-zhen (DZ) is an ancient type of acupuncture needle with a history dating back more than 2000 years. Unlike modern acupuncture needles, the DZ is not inserted subcutaneously, and is safely and commonly used at the bedside. The mechanisms underlying its effects are not known. In this study, we measured sublingual and cutaneous body temperature, pulse rate, oxygen pressure (PO2), oxygen saturation (sO2) and carbon dioxide pressure (PCO2) before and after DZ application in 25 healthy male volunteers. Serum levels of catecholamines (adrenaline, noradrenaline and dopamine) and white blood cells (WBCs;ratio and number) were traced for one week. Soon after DZ application, pulse rate, body temperature, PO2 and sO2 all decreased. The serum levels of adrenaline and noradrenaline increased, indicating sympathetic dominance, and the number of granulocytes was elevated. One week after DZ application, the number of lymphocyte increased. We therefore suggest that DZ affects body temperature, pulse rate, catecholamine secretion and immune function by inducing transient sympathetic dominance via actions on the autonomic nervous system. These effects are similar to the effects observed with modern needles, which are inserted subcutaneously. Therefore, we consider DZ treatment to be advantageous and safe in modern clinical practice, especially in post-surgical and terminal care, as it avoids the issues with infection and tissue damage sometimes seen with modern acupuncture needles.展开更多
The di-zhen (DZ) is an ancient type of acupuncture needle with a history dating back to more than 2000 years. Unlike modern acupuncture needles, the DZ is not inserted subcutaneously and is considered to be safe for c...The di-zhen (DZ) is an ancient type of acupuncture needle with a history dating back to more than 2000 years. Unlike modern acupuncture needles, the DZ is not inserted subcutaneously and is considered to be safe for common use, even at the bedside of terminally ill patients. In this case study, DZ application was selected and applied 14 times on a 92-year-old patient who had suffered severe oliguria along with administration of diuretics. Urine volume increased 12 out of 14 times following DZ treatment;however, the other two times it was ineffective. To investigate the reason and the differences in effective/ineffective DZ application, two internal conditions (effective vs ineffective) were compared by analyzing daily nursing reports (vital signs such as blood pressure, urine volume and body temperature) and weekly clinical data (including renal, liver and immune function, urea nitrogen, creatinine, ALT, AST, the ratio and number of leukocytes, erythrocytes). DZ application increased urine volume via a transient modification of the autonomic nervous system when internal homeostasis was maintained. Aging populations, who often have several diseases and medications, are rapidly increasing in developed countries. Therefore, the study and application of DZ may contribute to a reduction in medical costs, which have been rapidly and heavily expanding recently.展开更多
Many women track their daily basal body temperature (BBT), an important factor in reproductive status, as a part of fertility self-management. This study involved 135 patients who had undergone conventional infertilit...Many women track their daily basal body temperature (BBT), an important factor in reproductive status, as a part of fertility self-management. This study involved 135 patients who had undergone conventional infertility treatment;they had weekly acupuncture treatment and we assessed BBT, menstrual cycle, menstrual period and menstrual bleeding amount pre- and post-treatment. We also analyzed the rate of insufficient description of reproductive parameters, comparing patients who had delivered a baby with those who had a miscarriage and those who did not become pregnant. Menstrual cycle and period did not show notable changes pre- and post-acupuncture treatment in all groups. Menstrual bleeding amount decreased in the no-pregnancy group. There was a suggestion that acupuncture decreased very long menstrual cycle (e.g. bimonthly) to monthly. The insufficient description rate of menstrual bleeding amount was high in all groups. Weekly discussion about monitoring reproductive parameters could improve patients’ awareness in self-management. To prevent miscarriage patients needed psychological and medical advice for careful self-management in pregnancy and menstrual cycle.展开更多
We studied the efficiency of acupuncture for patients who were unable to give birth though they had experienced conventional infertility treatment for more than 2 years by medical specialists. We then investigated cha...We studied the efficiency of acupuncture for patients who were unable to give birth though they had experienced conventional infertility treatment for more than 2 years by medical specialists. We then investigated characteristics of difficult pregnancy cases with measurement of body temperature and observation of basal body temperature (BBT) charts. Thirty-three patients had acupuncture every week for more than 2 years and 17 of them delivered. At the same time, their cutaneous body temperature was measured at five locations. Moreover, patients and acupuncturists had a weekly discussion of the patient’s BBT chart. The delivery group showed more balanced and higher cutaneous body temperatures than the miscarriage and no pregnancy groups. The delivery group showed a smooth increase in the BBT chart while the miscarriage group showed a specific pattern in shifting temperatures from low to high zones. Acupuncture might suppress excess sympathetic dominance, which induced hyperthermia as well as interruption of pregnancy. Additionally, weekly discussion and medical advice could help patients. However, further study of males, healthy women, or larger, comparative studies exploring the social and cultural background of other countries were needed to add support to these factors.展开更多
The importance of sleep has been described in proverbs such as “the early bird catches the worm”. However, there are few scientific reports on the effects of early rising. Therefore, early risers (Group E) and late ...The importance of sleep has been described in proverbs such as “the early bird catches the worm”. However, there are few scientific reports on the effects of early rising. Therefore, early risers (Group E) and late risers (Group L) were compared and the number and ratio of leukocytes, body temperature, glucose and its associated hormones were studied. Furthermore, each group was divided into two groups by the duration of sleep and the following four groups were compared: early risers with short sleep (Group E-S);early risers with long sleep (Group E-L);late risers with short sleep (Group L-S);and late risers with long sleep (Group L-L). Then, compared with Group L, Group E showed lower numbers and ratio of granulocytes and a higher ratio of lymphocytes showing parasympathetic nerve dominance. Group E showed higher levels of glucose and its related hormones than Group L, indicating sympathetic nerve dominance. Compared with Groups E-S and L-S, Groups E-L and L-L showed lower glucose and cortisol levels, respectively. These results indicated that early rising might affect leukocyte subsets, and adequate duration of sleep could decrease levels of glucose via modification of the autonomic nervous system.展开更多
Physicians often observe patients’ complexion (their natural skin color) as an indicator of health. The complexion may depend on the internal environment, however, very few researchers studied its evidence. We previo...Physicians often observe patients’ complexion (their natural skin color) as an indicator of health. The complexion may depend on the internal environment, however, very few researchers studied its evidence. We previously reported various benefits of a mild hyperthermia treatment on human health using the nano-mist sauna (NMS), including acceleration of gas exchange (O2 and CO2) in the venous blood, enhancement of immunity, and the modulation of autonomic nervous system. However, the effects of NMS on skin appearance are unknown. There is a historical and widespread belief that mild hyperthermic treatments such as hot springs are good for improving skin appearance. However, the effect of NMS on the skin appearance has not been examined. In the present study, we examined the color of venous blood using the CIELAB (a color space specified by the French Commission internationale de l’éclairage) method, and then compared the color changes before and after NMS stimulation. Next, we examined correlations of blood gas parameters with color elements of the venous blood, which are highly dependent on oxygen. Our results suggest that the colors and appearance of the face depend on the internal environment, because there are numerous vessels under the skin. Thus, the color of the venous blood may provide medical evidence of changes in complexion. This new method may be useful for assessment of medical complexion by physicians, for use in determining internal health based on skin color information.展开更多
The objective of this study was to determine how traditional Japanese style bathing could promote good health. Using healthy volunteers, we assessed body temperature (core and cutaneous), red blood cells, white blood ...The objective of this study was to determine how traditional Japanese style bathing could promote good health. Using healthy volunteers, we assessed body temperature (core and cutaneous), red blood cells, white blood cells (WBCs), venous blood gas parameters (PO2, SO2, PCO2, TCO2, HCO3, and pH), weight loss (which may indicate sweat volume), and the time until sweating before and after bathing. We simultaneously conducted a double-blind clinical trial using a bath additive group and a control group to investigate the effect of a bath additive on the same parameters. We found that bathing increased the core and cutaneous body temperature, as well as PO2, SO2, and blood pH. All of the subjects also showed increases in heart rate and weight loss (sweat volume). After bathing, the number and ratio of granulocytes increased while the number and ratio of lymphocytes decreased. These results tended to be emphasized in the bath additive group;however, significant between-group differences were not detected. Our results indicated that bathing improved blood circulation and had a modulatory effect on the autonomic nervous system. This suggested that traditional Japanese style bathing might contribute to good health and longevity;however, additional larger-scale studies were needed to confirm or refute this conclusion.展开更多
The internal environment in tumor-bearing mice was investigated in detail. When EL-4 lymphoma cells (5 × 106 cells/mouse) were intraperitoneally inoculated into C57BL/6 mice, approximately 70% of the mice died by...The internal environment in tumor-bearing mice was investigated in detail. When EL-4 lymphoma cells (5 × 106 cells/mouse) were intraperitoneally inoculated into C57BL/6 mice, approximately 70% of the mice died by day 24. In this regard, the internal environment was compared between control mice, surviving mice and tumor-bearing mice which died. The most prominent sign was hypothermia (<34?C from day 16) seen in tumor-bearing mice which died. Control mice and surviving mice did not show such hypothermia (around 38?C). Other changes, including anemia and lymphocytopenia, were also seen in tumor-bearing mice which died, but not in control mice and surviving mice. Immunological study revealed that NKT cells, which have been previously identified to be the major effector lymphocytes against EL-4 cells, almost disappeared, especially in the liver of tumor-bearing mice which died. These results suggest that a specific internal environment might be required for continuous tumor growth in vivo. Such internal environmental factors include hypothermia, ane- mia and severe immunosuppression.展开更多
Body temperature is an important clinical indicator of health and illness. Many studies of human body temperature have been conducted;however, there are no studies that compare the body temperatures of humans and othe...Body temperature is an important clinical indicator of health and illness. Many studies of human body temperature have been conducted;however, there are no studies that compare the body temperatures of humans and other homeothermic animals. Twenty-six homeothermic animal species, including humans, were selected and characteristics of their internal environment were studied based on previous reports. The studied species were divided into two groups based on habitat (eight aquatic and eighteen terrestrial species) and three groups based on diet (carnivores, herbivores, and omnivores). Body temperatures, erythrocyte counts, and lymphocyte percentages were compared between species and between groups. Our results showed that carnivores had lower body temperatures and erythrocyte numbers than herbivores, and lower lymphocyte ratios than both herbivores and omnivores. Aquatic mammals that experienced a second adaptation event during their evolutionary process had lower body temperatures and lymphocyte ratios than terrestrial animals. These results suggest that excessive adaptation induced by stress or a change in environment may result in relative hypothermia and lymphocytopenia, features that aquatic mammals with stressful evolutionary backgrounds share with human cancer patients. However, our study is based on analysis of previous observations and reports, and further research (e.g., larger-scale studies) is needed to support this hypothesis.展开更多
基金Supported by The National Natural Science Foundation of China,No.30671899,No.30540012
文摘AIM:To investigate the stress-induced apoptosis of natural killer(NK)cells and the changes in their killing activity in mouse livers.METHODS:A restraint stress model was established in mice.Flow cytometry was employed to measure the percentage of NK cells and the changes in their absolute number in mouse liver.The cytotoxicity of hepatic and splenic NK cells was assessed against YAC-1 target cells via a 4 h 51Cr-release assay.RESULTS:The restraint stress stimulation induced the apoptosis of NK cells in the liver and the spleen,which decreased the cell number.The number and percentage of NK cells in the spleen decreased.However,the number of NK cells in the liver decreased,whereas the percentage of NK cells was significantly increased.The apoptosis of NK cells increased gradually with prolonged stress time,and the macrophage-1(Mac-1)+NK cells were more susceptible to apoptosis than Mac-1-NK cells.Large numbers of Mac-1-NK cells in the liver,which are more resistant to stress-induced apoptosis,were observed than the Mac-1-NK cells in the spleen.The stress stimulation diminished the killing activity of NK cells in the spleen was significantly decreased,but the retention of numerous Mac-1-NK cells in the liver maintained the killing ability.CONCLUSION:Significant stress-induced apoptosis was observed among Mac-1+NK cells,but not Mac-1-NK cells in the mouse liver.Stress stimulation markedly decreased the killing activity of NK cells in the spleen but remained unchanged in the liver.
文摘In a series of our recent studies, stress was found to induce simultaneously hypothermia and hyperglycemia. These conditions are beneficial to obtain prompt force which depends on the glycolysis pathway and to escape emergency. Since we have noticed that such conditions resemble the internal environment seen in some cancer patients, it was investigated whe- ther such conditions were accompanied with other patients. We selected patients with early and advanced cancer. Body temperature and other parameters including blood gas contents were examined. A difference was seen in body temperature, namely, many patients showed hypothermia, irrespective of cancer stages. Fur- ther characterization of other parameters show- ed that hypothermia and hyperglycemia existed in many patients. They had immunosuppressive state and anemia. Blood gas analysis showed that oxygen contents were low and carbon dioxide contents were high in patients. These results suggest a possibility that the internal environment seen in patients is responsible to induce onset of disease and to maintain their cell growth, because cancer cells have an energy system of predominant glycolysis. Although hypothermia, hypoxia and hyperglycemia are important to activate the glycolysis pathway and to escape from emergency, such responses suppress the mitochondrial pathway for long span and may result in carcinogenesis.
文摘The di-zhen (DZ) is an ancient type of acupuncture needle with a history dating back more than 2000 years. Unlike modern acupuncture needles, the DZ is not inserted subcutaneously, and is safely and commonly used at the bedside. The mechanisms underlying its effects are not known. In this study, we measured sublingual and cutaneous body temperature, pulse rate, oxygen pressure (PO2), oxygen saturation (sO2) and carbon dioxide pressure (PCO2) before and after DZ application in 25 healthy male volunteers. Serum levels of catecholamines (adrenaline, noradrenaline and dopamine) and white blood cells (WBCs;ratio and number) were traced for one week. Soon after DZ application, pulse rate, body temperature, PO2 and sO2 all decreased. The serum levels of adrenaline and noradrenaline increased, indicating sympathetic dominance, and the number of granulocytes was elevated. One week after DZ application, the number of lymphocyte increased. We therefore suggest that DZ affects body temperature, pulse rate, catecholamine secretion and immune function by inducing transient sympathetic dominance via actions on the autonomic nervous system. These effects are similar to the effects observed with modern needles, which are inserted subcutaneously. Therefore, we consider DZ treatment to be advantageous and safe in modern clinical practice, especially in post-surgical and terminal care, as it avoids the issues with infection and tissue damage sometimes seen with modern acupuncture needles.
文摘The di-zhen (DZ) is an ancient type of acupuncture needle with a history dating back to more than 2000 years. Unlike modern acupuncture needles, the DZ is not inserted subcutaneously and is considered to be safe for common use, even at the bedside of terminally ill patients. In this case study, DZ application was selected and applied 14 times on a 92-year-old patient who had suffered severe oliguria along with administration of diuretics. Urine volume increased 12 out of 14 times following DZ treatment;however, the other two times it was ineffective. To investigate the reason and the differences in effective/ineffective DZ application, two internal conditions (effective vs ineffective) were compared by analyzing daily nursing reports (vital signs such as blood pressure, urine volume and body temperature) and weekly clinical data (including renal, liver and immune function, urea nitrogen, creatinine, ALT, AST, the ratio and number of leukocytes, erythrocytes). DZ application increased urine volume via a transient modification of the autonomic nervous system when internal homeostasis was maintained. Aging populations, who often have several diseases and medications, are rapidly increasing in developed countries. Therefore, the study and application of DZ may contribute to a reduction in medical costs, which have been rapidly and heavily expanding recently.
文摘Many women track their daily basal body temperature (BBT), an important factor in reproductive status, as a part of fertility self-management. This study involved 135 patients who had undergone conventional infertility treatment;they had weekly acupuncture treatment and we assessed BBT, menstrual cycle, menstrual period and menstrual bleeding amount pre- and post-treatment. We also analyzed the rate of insufficient description of reproductive parameters, comparing patients who had delivered a baby with those who had a miscarriage and those who did not become pregnant. Menstrual cycle and period did not show notable changes pre- and post-acupuncture treatment in all groups. Menstrual bleeding amount decreased in the no-pregnancy group. There was a suggestion that acupuncture decreased very long menstrual cycle (e.g. bimonthly) to monthly. The insufficient description rate of menstrual bleeding amount was high in all groups. Weekly discussion about monitoring reproductive parameters could improve patients’ awareness in self-management. To prevent miscarriage patients needed psychological and medical advice for careful self-management in pregnancy and menstrual cycle.
文摘We studied the efficiency of acupuncture for patients who were unable to give birth though they had experienced conventional infertility treatment for more than 2 years by medical specialists. We then investigated characteristics of difficult pregnancy cases with measurement of body temperature and observation of basal body temperature (BBT) charts. Thirty-three patients had acupuncture every week for more than 2 years and 17 of them delivered. At the same time, their cutaneous body temperature was measured at five locations. Moreover, patients and acupuncturists had a weekly discussion of the patient’s BBT chart. The delivery group showed more balanced and higher cutaneous body temperatures than the miscarriage and no pregnancy groups. The delivery group showed a smooth increase in the BBT chart while the miscarriage group showed a specific pattern in shifting temperatures from low to high zones. Acupuncture might suppress excess sympathetic dominance, which induced hyperthermia as well as interruption of pregnancy. Additionally, weekly discussion and medical advice could help patients. However, further study of males, healthy women, or larger, comparative studies exploring the social and cultural background of other countries were needed to add support to these factors.
文摘The importance of sleep has been described in proverbs such as “the early bird catches the worm”. However, there are few scientific reports on the effects of early rising. Therefore, early risers (Group E) and late risers (Group L) were compared and the number and ratio of leukocytes, body temperature, glucose and its associated hormones were studied. Furthermore, each group was divided into two groups by the duration of sleep and the following four groups were compared: early risers with short sleep (Group E-S);early risers with long sleep (Group E-L);late risers with short sleep (Group L-S);and late risers with long sleep (Group L-L). Then, compared with Group L, Group E showed lower numbers and ratio of granulocytes and a higher ratio of lymphocytes showing parasympathetic nerve dominance. Group E showed higher levels of glucose and its related hormones than Group L, indicating sympathetic nerve dominance. Compared with Groups E-S and L-S, Groups E-L and L-L showed lower glucose and cortisol levels, respectively. These results indicated that early rising might affect leukocyte subsets, and adequate duration of sleep could decrease levels of glucose via modification of the autonomic nervous system.
文摘Physicians often observe patients’ complexion (their natural skin color) as an indicator of health. The complexion may depend on the internal environment, however, very few researchers studied its evidence. We previously reported various benefits of a mild hyperthermia treatment on human health using the nano-mist sauna (NMS), including acceleration of gas exchange (O2 and CO2) in the venous blood, enhancement of immunity, and the modulation of autonomic nervous system. However, the effects of NMS on skin appearance are unknown. There is a historical and widespread belief that mild hyperthermic treatments such as hot springs are good for improving skin appearance. However, the effect of NMS on the skin appearance has not been examined. In the present study, we examined the color of venous blood using the CIELAB (a color space specified by the French Commission internationale de l’éclairage) method, and then compared the color changes before and after NMS stimulation. Next, we examined correlations of blood gas parameters with color elements of the venous blood, which are highly dependent on oxygen. Our results suggest that the colors and appearance of the face depend on the internal environment, because there are numerous vessels under the skin. Thus, the color of the venous blood may provide medical evidence of changes in complexion. This new method may be useful for assessment of medical complexion by physicians, for use in determining internal health based on skin color information.
文摘The objective of this study was to determine how traditional Japanese style bathing could promote good health. Using healthy volunteers, we assessed body temperature (core and cutaneous), red blood cells, white blood cells (WBCs), venous blood gas parameters (PO2, SO2, PCO2, TCO2, HCO3, and pH), weight loss (which may indicate sweat volume), and the time until sweating before and after bathing. We simultaneously conducted a double-blind clinical trial using a bath additive group and a control group to investigate the effect of a bath additive on the same parameters. We found that bathing increased the core and cutaneous body temperature, as well as PO2, SO2, and blood pH. All of the subjects also showed increases in heart rate and weight loss (sweat volume). After bathing, the number and ratio of granulocytes increased while the number and ratio of lymphocytes decreased. These results tended to be emphasized in the bath additive group;however, significant between-group differences were not detected. Our results indicated that bathing improved blood circulation and had a modulatory effect on the autonomic nervous system. This suggested that traditional Japanese style bathing might contribute to good health and longevity;however, additional larger-scale studies were needed to confirm or refute this conclusion.
文摘The internal environment in tumor-bearing mice was investigated in detail. When EL-4 lymphoma cells (5 × 106 cells/mouse) were intraperitoneally inoculated into C57BL/6 mice, approximately 70% of the mice died by day 24. In this regard, the internal environment was compared between control mice, surviving mice and tumor-bearing mice which died. The most prominent sign was hypothermia (<34?C from day 16) seen in tumor-bearing mice which died. Control mice and surviving mice did not show such hypothermia (around 38?C). Other changes, including anemia and lymphocytopenia, were also seen in tumor-bearing mice which died, but not in control mice and surviving mice. Immunological study revealed that NKT cells, which have been previously identified to be the major effector lymphocytes against EL-4 cells, almost disappeared, especially in the liver of tumor-bearing mice which died. These results suggest that a specific internal environment might be required for continuous tumor growth in vivo. Such internal environmental factors include hypothermia, ane- mia and severe immunosuppression.
文摘Body temperature is an important clinical indicator of health and illness. Many studies of human body temperature have been conducted;however, there are no studies that compare the body temperatures of humans and other homeothermic animals. Twenty-six homeothermic animal species, including humans, were selected and characteristics of their internal environment were studied based on previous reports. The studied species were divided into two groups based on habitat (eight aquatic and eighteen terrestrial species) and three groups based on diet (carnivores, herbivores, and omnivores). Body temperatures, erythrocyte counts, and lymphocyte percentages were compared between species and between groups. Our results showed that carnivores had lower body temperatures and erythrocyte numbers than herbivores, and lower lymphocyte ratios than both herbivores and omnivores. Aquatic mammals that experienced a second adaptation event during their evolutionary process had lower body temperatures and lymphocyte ratios than terrestrial animals. These results suggest that excessive adaptation induced by stress or a change in environment may result in relative hypothermia and lymphocytopenia, features that aquatic mammals with stressful evolutionary backgrounds share with human cancer patients. However, our study is based on analysis of previous observations and reports, and further research (e.g., larger-scale studies) is needed to support this hypothesis.
