Effect of Auriculotherapy on the Plasma Concentration of Biomarkers in Individuals with Knee Osteoarthritis.

Knee osteoarthritis (KOA) is one of the most frequent noncommunicable diseases with pain associated symptoms and affects the musculoskeletal system. Various forms of treatment can be indicated, and nonpharmacological treatment is also an available option for the management of KOA individuals. For instance, auriculotherapy (AT) is one possible procedure associated with the Traditional Chinese Medicine for dealing with KOA. It is believed that the concentration of certain biomarkers could be altered in individuals with KOA after AT. The aim of this study was to evaluate the effect of AT on plasma concentration of biomarkers in KOA individuals. This intervention is a controlled trial. Twenty-one subjects were grouped in two groups and submitted to AT with the stimulation of the Shen Men, kidney, and knee points in the treatment group or different points in the control group, once a week for 5 weeks. Blood was collected before the beginning of protocols and a week after the last session. Kolmogorov-Smirnov and Wilcoxon tests were performed, and a p ≤ 0.05 was considered statistically significant. Hematological parameters did not show any significant variation between the control group and treated group. Concerning the biochemical parameters, a significant reduction of direct bilirubin (from 43.31 ± 22.10 to 21.21 ± 5.30 µmol/L, p = 0.003), aspartate aminotransferase (from 0.48 ± 0.16 to 0.38 ± 0.09 µKat/L, p = 0.010), and triglycerides (from 7.04 ± 2.90 to 5.45 ± 2.57 mmol/L, p = 0.008) in the treated group was obtained. In conclusion, the analysis of results suggests that AT might be a useful intervention for the management of KOA individuals.

Symptoms of long-term exposure to moxa smoke in acupuncturists: a correlation analysis.

OBJECTIVE: To investigate the effects of long-term exposure to moxa smoke on acupuncturists and to consider the association between physical symptoms and gender, age, secondhand smoke (SHS) exposure, and the duration of exposure. METHODS: A self-report, web-based questionnaire was used to evaluate the effects of moxa smoke on acupuncturists. Logistic regression was used to analyze the relationship between physical symptoms and possible correlative factors. RESULTS: A total of 858 questionnaires were analyzed. The data showed that 42.42% of acupuncturists had been exposed to moxa smoke for 5-10 years. The most frequent symptom was tearing (32.98%) and the least frequent symptom was asthma (5.24%). Logistic regression analysis showed that female acupuncturists were slightly more susceptible to cough and tearing than males (cough: OR: 1.583, 95% CI: 1.079, 2.321, P = 0.019; tearing: OR: 1.519, 95% CI: 1.094, 2.108, P = 0.013). Acupuncturists aged over 25 years reported a slightly lower incidence of eye itchiness than those aged under 25 years (26-40 years: OR: 0.604, 95% CI: 0.379, 0.965, P = 0.035; over 40 years: OR: 0.330, 95% CI: 0.114, 0.958, P = 0.042). Ophthalmodynia occurred less in acupuncturists aged 26-40 years (OR: 0.591, 95% CI: 0.359, 0.970, P = 0.038) than in those younger than 25 years. The only association between prevalence of symptoms and tobacco use and SHS exposure was that smokers had a lower occurrence of phlegm in the throat (OR: 0.579, 95% CI: 0.392, 0.856, P = 0.006). Shortness of breath was less frequent in participants exposed to moxa smoke for more than 5 years (5-10 years: OR: 0.400, 95% CI: 0.204, 0.785, P = 0.008; 11-20 years: OR: 0.392, 95% CI: 0.178, 0.864, P = 0.02), but a slightly higher incidence of eye itchiness was found in those with over 20 years of moxa exposure (OR: 4.200, 95% CI: 1.344, 3.128, P = 0.014). CONCLUSION: The most frequent symptom of moxa smoke exposure in acupuncturists was tearing. The association of symptoms with age and duration of exposure to moxa smoke were rather complicated; hence, care should be taken in drawing conclusions about the safety of moxa smoke based solely on its potentially harmful ingredients.

Regulating the Balance of Th17/Treg via Electroacupuncture and Moxibustion: An Ulcerative Colitis Mice Model Based Study.

AIM: To investigate the relationship between the effects of electroacupuncture/moxibustion and the balance of Th17/Treg in treating ulcerative colitis (UC) and to preliminary compare the effects of the above two methods. METHODS: DSS-induced UC mice were treated by electroacupuncture and moxibustion. Disease activity index (DAI) was scored; intestinal pathological structure and ultrastructure were observed. The levels of IL-2, IL-6, IL-10, IL-17A, IL-17F, and TGF-ß in plasma were measured by ELISA. The percentages of Treg and Th17 in spleen lymphocytes were analyzed by flow cytometry. Also, the expressions of TLR2, TLR4, RORγt, and FOXP3 in the distal colon were detected by immunohistochemistry or western blot. RESULTS: Both electroacupuncture and moxibustion can relieve UC. These effects are further supported by ELISA results. In addition, the ratio of Treg and Th17 in spleen lymphocytes and the expression of TLR2 and TLR4 are significantly improved. Also, the expression of RORγt and FOXP3 in distal colon were improved. Besides, the effect of moxibustion is better than that of electroacupuncture on TLR2, TLR4, and FOXP3 expression (P < 0.05). CONCLUSION: Both electroacupuncture and moxibustion may ameliorate UC by regulating the balance of Th17/Treg. Whether moxibustion has better efficacy than electroacupuncture needs further study.

Laser stimulation of the acupoint 'Zusanli' (ST.36) on the radiopharmaceutical biodistribution in Wistar rats.

Laser used to stimulate acupoints is called laser acupuncture (LA). It is generally believed that similar clinical responses to manual acupuncture can be achieved. Here we analysed the effects of the laser (904 nm) at the 'Zusanli' acupoint (ST.36) of the stomach meridian on the biodistribution of the radiopharmaceutical Na(99m)TcO4. Wistar rats were divided into control (CG) and experimental groups (EG). The EG were exposed daily to the laser (904 nm) at ST.36 with 1 joule/min (40 mW/cm(2)) for 1 min. The animals of the CG were not exposed to laser at all. On the 8th day after LA, the animals were sedated and Na(99m)TcO4 was administered. After 10 min, the animals were all sacrificed and the organs removed. The radioactivity was counted in each organ to calculate the percentage of radioactivity of the injected dose per gram (%ATI/ g). Comparison of the %ATI/g in EG and CG was performed by Mann-Whitney test. The %ATI/g was significantly increased in the thyroid due to the stimulation of the ST.36 by laser. It is possible to conclude that the stimulation of ST.36 does lead to biological phenomena that interfere with the metabolism of the thyroid.

Revealing Potential Biomarkers of Functional Dyspepsia by Combining 1H NMR Metabonomics Techniques and an Integrative Multi-objective Optimization Method.

Metabonomics methods have gradually become important auxiliary tools for screening disease biomarkers. However, recognition of metabolites or potential biomarkers closely related to either particular clinical symptoms or prognosis has been difficult. The current study aims to identify potential biomarkers of functional dyspepsia (FD) by a new strategy that combined hydrogen nuclear magnetic resonance ((1)H NMR)-based metabonomics techniques and an integrative multi-objective optimization (LPIMO) method. First, clinical symptoms of FD were evaluated using the Nepean Dyspepsia Index (NDI), and plasma metabolic profiles were measured by (1)H NMR. Correlations between the key metabolites and the NDI scores were calculated. Then, LPIMO was developed to identify a multi-biomarker panel by maximizing diagnostic ability and correlation with the NDI score. Finally, a KEGG database search elicited the metabolic pathways in which the potential biomarkers are involved. The results showed that glutamine, alanine, proline, HDL, ß-glucose, α-glucose and LDL/VLDL levels were significantly altered in FD patients. Among them, phosphatidycholine (PtdCho) and leucine/isoleucine (Leu/Ile) were positively and negatively correlated with the NDI Symptom Index (NDSI) respectively. Our procedure not only significantly improved the credibility of the biomarkers, but also demonstrated the potential of further explorations and applications to diagnosis and treatment of complex disease.

The mechanism of auriculotherapy: a case report based on the fractal structure of meridian system.

BACKGROUND: Chinese meridian system of acupuncture has recently been deciphered as the fractal continuum of neurovascular bundles and its smaller branches. The corresponding acupuncture mechanism of therapeutics has been attributed to the magneto-electric inductive effects of the meridian system via chaotic wave of nerve innervations and blood flow. Hence, based on the proposed theory, the important sensory organ of the ears should be able to exert its influence on visceral organs and peripheral limbs. This investigation aims to verify if such a possible correlation exists between an external region of the ear and the muscle of biceps brachii in the French auriculotherapy. MATERIALS AND METHODS: A region between the points of elbow and shoulder in the scaphoid fossa (upper arm), was chosen. Before the recording of surface electromyograms (EMGs), of the muscle of biceps brachii, two subjects were asked to carry out maximum voluntary isometric contractions (MVICs), of the arm. In addition, the same volunteers would be served as control group. Consequently, each subject was required to perform the three treatments of control, sham, and acupressure in random order. EMG signals were recorded for later analysis. RESULTS: Results indicate that the acupressure with finger at a specific point which bears possibly with a somatopic relation to the biceps brachii muscle can, in a man, modify the response of the EMGs associated with the corresponding muscle while the response of the acupressure of a sham point has different responses. Moreover, the MVIC parameters were higher in acupressure treatment than those of control and sham treatments for both subjects. CONCLUSION: In conclusion, the analysis of the findings permits us to speculate that the stimulation with the fingers in the scaphoid fossa of the ear presents electromyographic responses related to the biceps brachii muscle. Hence, the mechanism of French auriculotherapy could be derived from the same principle as that of the Chinese acupuncture.

The meridian system and mechanism of acupuncture: a comparative review. Part 3: Mechanisms of acupuncture therapies.

The human body is a hierarchical organism containing many levels of mutually interacting oscillatory systems. From the viewpoint of traditional Chinese medicine, health is a state of harmony emergent from the interactions of these systems and disease is a state of discord. Hence, human diseases are considered as disturbed functions rather than changed structures. Indeed, the change from normal to abnormal structure may be beneficent rather than maleficent. For example, when one kidney becomes twice the normal size following the destruction of the other kidney, it is good and not bad for us because we might be dead otherwise. Therefore, in Part 3 of this three-part series, emphasis is mainly laid on the acupuncture mechanisms of treating disturbed physiological functions rather than disordered structures. At first, the basic tenets of conventional neuroscience and cardiology are reevaluated so that clear understanding of how nervous and cardiovascular systems work together can be obtained. Then, the general principles of diagnosis and treatment in traditional Chinese medicine from the integrative perspective of complex dynamic systems are proposed. Finally, mechanisms of acupuncture therapies for treating 14 different categories of disorders will be elucidated via the magneto-electric inductive effects of the meridian system.

The meridian system and mechanism of acupuncture--a comparative review. Part 2: mechanism of acupuncture analgesia.

In traditional Chinese medicine (TCM), pain is never merely a sign of discomfort. It is usually an integral part of a particular disease or physiological malfunction. Thus pain should not be treated in isolation since it will disappear as soon as its cause is identified and removed. Hence, in this Part 2 of a three-part series, initially, clinical pathologies in modern medicine and TCM are compared. Then, the pain pathophysiologies of these two schools of thought are reviewed. In addition, certain unique features of acupuncture effects that any valid mechanism must account for are outlined. Finally, various mechanisms of acupuncture analgesia are reviewed. One plausible mechanism based on the meridian system of Part 1, i.e., the chaotic wave theory of fractal continuum in terms of the neurovascular network, is also proposed. It contends that the injury current due to acupuncture at an acupoint will trigger electromagnetic inductive effects so that the impedances of correlated neurovascular bundles are drastically changed. Two consequent scenarios are possible. (1) If the impedance of the meridian hugely mismatches with that of the brain after acupuncture, then the traveling wave of pain signal will be largely reflected back and only partially transmitted to the brain, hence pain relief can be achieved. (2) If the impedance of the meridian entirely matches that of the pain source after acupuncture, then the pain source would appear to be nonexistent to the brain, hence analgesia can be achieved. The former mechanism can be used to explain the relief for chronic pain and the latter one for acute pain. It is believed that the proposed mechanisms via match or mismatch of the impedances can explain how the acupuncture works not only in the treatment of pain, but also in various other therapies of Part 3.

The meridian system and mechanism of acupuncture-a comparative review. Part 1: the meridian system.

In traditional Chinese medicine (TCM), acupuncture has been used to heal various diseases and physiologic malfunctions in clinical practice for more than 2500 years. Due to its efficacy, acupuncture has been recommended by the World Health Organization in 1980 as an effective alternative therapy for 43 different disorders. Over the past few decades, various theories of the meridian system and mechanisms have been proposed to explain how acupuncture might work. Most of these mechanisms, however, cannot yet explain conclusively why acupuncture is efficacious in treating so many different diseases. A plausible mechanism has been unavailable until recently. This is the first of a three-part series that aims to provide a comparative review of the aforementioned topics. Part 1 reviews the current indications for acupuncture, basic concepts of TCM, and the essence of the meridian system. To establish a mathematically rigorous framework of TCM, the chaotic wave theory of fractal continuum is proposed. This theory is then applied to characterize the essence of the meridian system. Parts 2 and 3 will review the possible mechanisms of acupuncture analgesia and acupuncture therapies, respectively, based on biochemical, bioelectromagnetic, chaotic wave, and neurophysiologic approaches. It is sincerely hoped that this series of review articles can promote an understanding of the meridian system and acupuncture mechanisms to help patients in a logical and passionate way.

Physiological rhythms, dynamical diseases and acupuncture.

Physiological rhythms are ubiquitous and essential to our life. They usually interact with one another and also with the outside environment. Disappearance of normal rhythms and emergence of abnormal rhythms are called dynamical diseases. In this article, we will first review the current knowledge on the genesis of physiological rhythms. Then, models of rhythmic interactions among themselves and with external stimuli will be reviewed. Particular emphasis will be placed on the methods that can diagnose abnormal rhythms. Finally, treatment of dynamical diseases will be discussed. It turns out that the models of fractional Brownian motion and fractional Gaussian noise based on dynamical systems have the potential to become biomarkers in differentiating and evaluating normal from abnormal physiological rhythms in dynamical diseases. Meanwhile, in order to explain how acupuncture works, a feasible model of meridians based on communication networks is also included.

The cooperative phenomenon of autonomic nervous system in urine storage for Wistar rats.

The fractal dimension (FD) and spectral frequencies of physiological signals are two important indices in the study of physiological functions and dynamical diseases. The first index can be used to characterize the intensity and the second the rhythms of signals embedded in seemingly random data. Recent studies using both indices verified that synergic co-activations of bladder and external urethral sphincter (EUS) of Wistar rats were present during the voiding of urine. In this study, the primary aims were to (1) examine if the involved muscles in the lower urinary tract would be under similar coactivations during the urine storage phase, and (2) characterize quantitatively the sympathetic and parasympathetic nerve activities simultaneously. Eighteen experiments were performed on six intact adult female Wistar rats and then the electromyogram of EUS and cystometrogram of bladder were analyzed. Results indicated that the EUS did not contain any significant spectral frequencies in the storage phase. Furthermore, its FDs (1.5918 +/- 0.0157) indicated that no appreciable amount of signal intensities was observed in the EUS. On the other hand, the bladder exhibited parasympathetic frequency of 8 Hz with signal-to-noise ratio (SNR) = 19.9001 decibel (dB) for group mean, and sympathetic frequency of 19 Hz with SNR = 22.8330 dB for group mean. In addition, its FDs (1.4796 +/- 0.0092) indicated relatively persistent intensities during storage, as compared to that of EUS (1.5918 +/- 0.0157) with statistical significance (P < 0.01). We concluded that the EUS was not activated during the phase of storage. The bladder was under the cooperative, not antagonistic, sympathetic and parasympathetic nerve activities with discernible rhythmic frequencies and persistent intensities.

Dynamic performance evaluation on the synergy of micturition in spinal cord-injured female rats under pharmacological effects.

Recently, a temporal "coherent" fractal structure and synchronization of rhythms were proposed as two essential indicators for efficient voiding during micturition in female rats. The former was correlated with the intensity and the latter the frequency of physiological signals embedded in random noise. Studies using both indices confirmed that synergic co-activations of bladder and external urethral sphincter (EUS) of female rats were present during the voiding of urine. Therefore, it would be interesting to investigate if these two criteria could be used in the performance evaluation of pharmacological effects on spinal cord-injured rats during micturition. In this paper, the primary goals were to (1) examine if the involved muscles in the lower urinary tract would be under similar synergic co-activations during the administration of capsaicin (CAP) and resiniferatoxin (RTX), and (2) characterize quantitatively the differences of their nervous responses simultaneously. A total of 62 micturition experiments were performed on sixteen spinal cord-injured adult female Sprague-Dawley rats, and then the electromyograms of EUS and cystometrograms of bladder were analyzed. Results based on the aforementioned criteria indicated that the synergy of bladder and EUS during micturition by using RTX was better than that of the CAP. Furthermore, the residue urine volumes for rats under the former treatment were smaller than those of the rats under the latter treatment. Consequently, we concluded that the administration of RTX was more effective than CAP in facilitating voiding in the spinal cord-injured rats.

Effects of acupuncture at Neiguan (PC 6) on electroencephalogram.

The aim of this study was to investigate if there were any effects on the electroencephalogram (EEG) of human brain by the manual stimulation of Neiguan (PC 6) acupuncture site. In this paper, two groups of six healthy male volunteers of ages 27.6 +/- 14.2 (mean +/- SD) and 28.5 +/- 13.0 (mean +/- SD) and no neurological disease participated in this study. A digital storage of 12-channel EEG recorder was used and spectral analyses of the data set of 18 trials were obtained before, during, and after sham/ manual acupuncture. To minimize artefacts, all data were collected with the subjects alert but eyes closed. No significant changes (P > 0.05) were obtained for the sham acupuncture group. As for the manual acupuncture group, the needle was inserted perpendicularly into the PC 6 acupuncture site and manually stimulated about 15 to 30 seconds to achieve De Qi sensation. Needles were left in place for 30 min and then removed. Analysis of the EEG data due to acupuncture was compared to the baseline data and changes were obtained. First, all trials had an increase in the amplitude and power of the alpha band during manual acupuncture (P < 0.05) when compared with the baseline data. Secondly, in the mean time, the frequency peaks in alpha band of 12-channels were all synchronized with much smaller standard deviation (P < 0.01). Thirdly, the manual acupuncture effects of higher power and synchronized frequencies persisted for at least 10 minutes after the experiment (P < 0.05) and did not disappear immediately for all 18 experiments. Finally, we hypothesized that the higher power and synchronized rhythms in brain oscillations may have to do with autonomic nervous system.

Effects of acupuncture at Neiguan (PC 6) of the pericardial meridian on blood pressure and heart rate variability.

The aims of this study were to investigate (i) if and when the blood pressure would rise or fall and (ii) the associated changes of human heart rate variability (HRV) by manual stimulation of the Neiguan (PC 6) acupuncture site. In this paper, two groups of six healthy male volunteers with ranges of ages 20-56 and 20-55 and with no neurological diseases participated in this study. In order to minimize artefacts, the electrocardiogram (ECG) and radial arterial pulse pressure wave were collected with the subjects alert but eyes closed before, during, and after sham/manual acupuncture. No statistically significant changes (P > 0.05) were found in the sham acupuncture group. As for the manual acupuncture group, the needle was inserted into the PC 6 acupoint and manually stimulated about 15 to 30 seconds to achieve De Qi sensation. Needles were left in place for 30 min and then removed. Analysis of the data due to acupuncture was then compared with the baseline values. Results indicate that the blood pressures of different subject can either rise (P < 0.01) or fall (P < 0.01). To further determine the indicator for one subject who exhibited both rise and fall of blood pressures, 7 more trials were given conducted with the same protocol until statistically significant results were obtained (P < 0.01). We found that his change of blood pressure was highly correlated (p = -0.94 and -0.99 for rise and fall, respectively) with the ratio of the magnitude of pulse pressure to that of the dicrotic notch in the local radial pulse wave (P < 0.01). As to the heart rate variability (HRV) spectra, significant changes in the low frequency (LF) and very low frequency (VLF) ranges were also detected. These results indicate that the autonomic innervations of heart have been modified. However, the information on the power of LF, high frequency (HF), and LF/HF of HRV are not conclusive to statistically differentiate the sympathetic contribution from that of the parasympathetic nervous systems at present stage.

Synergic co-activation in forearm pronation.

Co-activations of agonist and antagonist muscles are believed to be present in voluntary limb movement. Recent studies indicate that such co-activations are either synergic or dyssynergic. The aims of this paper are to (1) develop a novel method that can extract both the intensity and frequency information from the recordings of the surface electromyograms (EMGs) of involved muscles, and (2) investigate if the involved muscles will be under synergic co-activation during voluntary forearm pronation for normal subjects and dyssynergic co-activation for patients with radial nerve palsy. We examined 11 healthy subjects and 4 patients with right-arm radial nerve palsy in this study. For the group of healthy subjects, each one of them was asked to perform 30 trials of voluntary forearm pronation and then 30 trials of passive pronation as control experiments. As to the second group of patients, each one was asked to perform only 15 trials of voluntary pronation due to the limitation and durability of their arms. The recordings of the surface EMGs included the short and long heads of the biceps brachii, the brachialis, the lateral head of the triceps brachii, brachioradialis, and pronator teres. Experimental results of the healthy group indicated that the surface EMGs of all muscles had no statistically significant changes in fractal dimensions (FDs) and spectral frequencies of the control experiments during passive pronation. Yet, during the voluntary pronation experiments, the surface EMGs of all muscle groups were temporally synchronized in frequencies with persistent intensities. Hence, all involved muscle groups were in synergic co-activation. Statistical results of the group mean values of FDs during rest vs. forearm pronation also revealed significant difference with p < 0.01 for healthy subjects. As to the group of patients, their EMGs could still have bursting activities, but the synchronized significant frequencies might be lacking or the intensities as indicated from their FDs would not be persistent. To further compare the FDs among the three different protocols, a mixed-model ANOVA and multiple comparison tests were performed. Finally, in order to illustrate the advantages of this novel method, we have compared it with the detrended fluctuation analysis (DFA). It is believed that this proposed method will have the potential to be a biomarker for evaluating dynamical disease in neuromuscular disorders.

Synergic co-activation of muscles in elbow flexion via fractional Brownian motion.

In reflex and volitional actions, co-activations of agonist and antagonist muscles are believed to be present. Recent studies indicate that such co-activations can be either synergic or dyssynergic. The aim of this paper is to investigate if the co-activations of biceps brachii, brachialis, and triceps brachii during volitional elbow flexion are in the synergic or dyssynergic state. In this study, two groups with each containing six healthy male volunteers participated. Each person of the first group performed 30 trials of volitional elbow flexion while each of the second group performed 30 trials of passive elbow flexion as control experiments. Based on the model of fractional Brownian motion, the intensity and frequency information of the surface electromyograms (EMGs) could be extracted simultaneously. No statistically significant changes were found in the control group. As to the other group, results indicated that the surface EMGs of all five muscle groups were temporally synchronized in frequencies with persistent intensities during each elbow flexion. In addition, the mean values of fractal dimensions for rest and volitional flexion states revealed significant differences with P < 0.01. The obtained positive results suggest that these muscle groups work together synergically to facilitate elbow flexion during the co-activations.

Fractal dimension estimation via spectral distribution function and its application to physiological signals.

Rhythmic signals from physiological systems usually have memory and long-term correlation. They can be modeled as fractional Brownian motion or fractional Gaussian noise depending on if the signals are derived from cumulative effects of nerves and muscles. That is, they can be treated as signals with fractional dimension, and the value of its fractal dimension can be used to characterize the intensity of physiological signals. In this communication, a novel method of dimension estimation based on the calculation of spectral distribution function of discrete-time fractional Gaussian noise using Legendre polynomials as basis set is proposed. The effectiveness of this proposed method is demonstrated in the dynamic behavior of detrusor of the bladder and external urethral sphincter during micturition.

Fractal dynamics and synchronization of rhythms in urodynamics of female Wistar rats.

Two phenomena are ubiquitous in physiological signals. First, they have temporal fractal structure. Secondly, they are rhythmic but with fluctuations. The fractal structure and rhythms can alter from normal to abnormal with disease or injury. Here, we demonstrate that a temporal "coherent" fractal structure and synchronization of rhythms are two essential features for concerted systemic functions in urodynamics of female Wistar rats. We report evidence on the dynamic interaction in the micturition reflex of lower urinary tract: the rhythms of detrusor of the bladder and external urethral sphincter are synchronized around 7 Hz and their fractal dimensions as functions of time are temporally "coherent" under 1.5 during voiding in order to facilitate the concerted process. On the other hand, in the spinal cord injured rats, either the temporal coherent structure of fractal or the underlying synchronization of rhythms is impaired, weakened, or absent. These results have potential implications in the diagnosis of the so-called "dynamical" diseases.