human
***TASK*** the task is to summarize an input biomedical literature in six sentences 
    ***INPUT*** the input is a biomedical literature 
    ***OUTPUT*** the output is the summary of an input biomedical literature in six sentences 
    ***DOCUMENTATION*** 
    ***EXAMPLES*** 
    Input: In October 2000 the German Federal Committee of Physicians and Health Insurers recommended that special Model Projects on Acupuncture ( “ Modellvorhaben Akupunktur ” ) be developed in order to determine the evidence -based role of acupuncture in the treatment of certain illnesses . This paper presents a summary of the main r and omised controlled trials performed as part of these projects , and the associated economic analyses . Overall the results show that acupuncture  is effective in practice for a range of chronic conditions , and it seems likely to have acceptable cost utility ( at least at a rate of ¢35 per session ) . Sham acupuncture , in the form of minimal off-point needling in a therapeutic context , also appears to be effective , being no different to prophylactic medication in migraine , and superior to guideline -based st and ard care in chronic low back pain . In patients recruited to  acupuncture  trials , the response to treatment does not differ between those that agree to be r and omised and those that do not . This suggests that the results of the pragmatic Acupuncture in Routine Care studies are applicable to patients from the general population who express a preference for  acupuncture . In conclusion ,  acupuncture  appears to be effective in a range of chronic conditions and it seems to have acceptable cost-effectiveness in Western health economic terms . These programmes of research do not confirm the hypothesis that needling at specific points is essential to achieve satisfactory clinical effects of acupuncture . Sham acupuncture , in the form of minimal off-point needling in a therapeutic context , is unlikely to be an inactive placebo . In April 2006 , the German health authorities decided that acupuncture would be included into routine reimbursement by social health insurance funds for chronic low back pain and chronic osteoarthritis of the knee Needle stimulation ( acupuncture ) has recently been shown to increase blood flow in the tibialis anterior muscle and overlying skin in healthy subjects ( HS ) and patients with fibromyalgia ( FM ) . The aim of the present study was to examine the effect of needle stimulation on local blood flow in the trapezius muscle and overlying skin in HS and two groups of patients suffering from chronic pain in the trapezius muscle , i.e. , FM and work-related trapezius myalgia ( TM ) patients . Two modes of needling , deep muscle stimulation ( Deep ) and subcutaneous needle insertion ( SC ) , were performed at the upper part of the shoulder and blood flow was monitored for 60 min post-stimulation . Blood flow changes were measured non-invasively by using a new application of photoplethysmography .  Increased blood flow in the trapezius muscle and overlying skin was found in all three groups following both Deep and SC . In HS , Deep was superior to SC in increasing skin and muscle blood flow , whereas in FM , SC was as effective as , or even more effective , than Deep . In the severely affected TM patients , no differences were found between the stimuli , and generally , a lesser blood flow response to the stimuli was found . At Deep , the muscle blood flow increase was significantly larger in HS , compared to the two patient groups . Positive correlations were found between muscle blood flow at Deep and pressure pain threshold in the trapezius muscle , neck movement and pain experienced at the stimulation , and negative correlations were found with spontaneous pain-related variables , symptom duration and age , pointing to less favorable results with worsening of symptoms , and to the importance of nociceptor activation in blood flow increase . It was hypothesized that the different patterns of muscle blood flow response to the needling may mirror a state of increased sympathetic activity and a generalized hypersensitivity in the patients . The intensity of stimulation should be taken into consideration when applying local needle stimulation ( acupuncture ) in order to increase the trapezius muscle blood flow in chronic pain conditions In 14 healthy female subjects , the effects of needle stimulation ( acupuncture ) on skin and muscle blood flow were investigated using a non-invasive custom- design ed probe and photoplethysmography ( PPG ) . In r and omised order , 2–7 days apart , three modes of needle stimulation were performed on the anterior aspect of the tibia : superficial insertion ( SF ) , insertion into the anterior tibial muscle ( Mu ) , and insertion into the muscle including manipulation of the needle in order to elicit a distinct sensation of distension , heaviness or numbness ( DeQi ) . Before intervention , the subjects rested for 30 min . After the intervention , the needle was left in situ for 20 min . Blood flow recordings were performed intermittently from 10 min prior to the intervention to the end of the trial . In a fourth session , serving as control , corresponding measurements were performed without any needle stimulation . Area under curve was calculated for 5-min periods prior to and after stimulation , respectively , and for the remaining 15-min period after stimulation . Compared to the control situation , muscle blood flow increased following both Mu and DeQi for 20 min , with the latter being more pronounced for the initial 5 min . Skin blood flow increased for 5 min following DeQi . However , no increase was found following SF . The DeQi stimulation was preceded by higher visual analogue scale ratings of anxiety prior to stimulation , which might have influenced skin blood flow to some extent . The results indicate that the intensity of the needling is of importance , the DeQi stimulation result ing in the most pronounced increase in both skin and muscle blood flow Rapidly repeated imaging of the left middle fingertip skin blood perfusion was performed in 51 healthy volunteers ( mean age±SD : 25.3±7.6 years ) prior to , immediately after and in the early reperfusion phase following introduction of an acupuncture needle at the Neiguan point ( Pe . 6 ) and at a placebo point respectively , using a Laser Doppler Perfusion Imager ( LDPI ) . The average skin perfusion of the fingertip was calculated for each image and used as an indicator of the microvascular response to the acupuncture needle introduction . The results of this r and omised , placebo-controlled , cross-over study showed significant differences ( p≤0.001 ) in the immediate skin blood perfusion response when needling is performed in an acupuncture point ( Neiguan ) and a placebo point , with a more pronounced reduction in skin blood perfusion when needling the acupuncture point . In the early reperfusion phase , however , a substantial increase in skin perfusion was observed that amounted to about 18 % of the level prior to needle introduction , irrespective of the site of needle application . In a single individual it was demonstrated that the vasodilatation following needling in the acupuncture point persisted for a more extended time period . These results suggest that the LDPI technology may be useful in visualising and quantifying the peripheral vascular effects of acupuncture on the microcirculation Although it is widely used , the mechanisms and effects of acupuncture on pain are not completely understood . Recently , increased nitric oxide ( NO ) synthase activity has been found in meridians and acupoints . Because NO is a key regulator of local circulation , and because change in circulation can affect the development and persistence of pain , we propose that acupuncture might regulate NO levels . We studied the effects of acupuncture on local NO levels and circulation in a r and omized , double-blind , crossover study with 20 volunteers , each of whom underwent one session each of real and noninvasive sham acupuncture in a single h and and forearm with a 1-wk interval between treatments . NO concentration in the plasma from the acupunctured arm was significantly increased by 2.8 ± 1.5 μmol/L at 5 min and 2.5 ± 1.4 μmol/L at 60 min after acupuncture . Blood flow in palmar subcutaneous tissue of the acupunctured arm also increased , and this correlated with the NO increase . These changes were not observed in noninvasive sham-acupunctured h and s and forearms . In conclusion , acupuncture increases the NO level in treated regions and thereby increases local circulation . These regulatory effects might contribute to pain relief provided by acupuncture Acupuncture has become a widely used treatment modality in various musculoskeletal pain conditions . Acupuncture is also shown to enhance blood flow and recovery in surgical flaps . The mechanisms behind the effect on blood flow were suggested to rely on vasoactive substances , such as calcitonin gene-related peptide , released from nociceptors by the needle stimulation . In a previous study on healthy subjects , one needle stimulation into the anterior tibial muscle was shown to increase both skin and muscle blood flow . The aim of this study was to examine the effect of needle stimulation on local blood flow in the anterior tibial muscle and overlying skin in patients suffering from a widespread chronic pain condition . Fifteen patients with fibromyalgia ( FM ) participated in the study . Two modes of needling , deep muscle stimulation and subcutaneous needle insertion were performed at the upper anterior aspect of the tibia , i.e. , in an area without focal pathology or ongoing pain in these patients . Blood flow changes were assessed non-invasively by photoplethysmography ( PPG ) . The results of the present study were partly similar to those earlier found at a corresponding site in healthy female subjects , i.e. , deep muscle stimulation result ed in larger increase in skin blood flow ( mean ( SE ) ) : 62.4 % ( 13.0 ) and muscle blood flow : 93.1 % ( 18.6 ) , compared to baseline , than did subcutaneous insertion ( mean ( SE ) skin blood flow increase : 26.4 % ( 6.2 ) ; muscle blood flow increase : 46.1 % ( 10.2 ) ) . However , in FM patients subcutaneous needle insertion was followed by a significant increase in both skin and muscle blood flow , in contrast to findings in healthy subjects where no significant blood flow increase was found following the subcutaneous needling . The different results of subcutaneous needling between the groups ( skin blood flow : p=0.008 ; muscle blood flow : p=0.027 ) may be related to a greater sensitivity to pain and other somatosensory input in FM Background and Purpose : Various research ers have studied the effects of transcutaneous electrical nerve stimulation ( TENS ) on hemodynamics . The purpose of this study was to examine the effects of TENS on local blood flow in the trapezius muscle and overlying skin . Subjects : Thirty-three women who were healthy , aged 25 to 55 years , were r and omly assigned to receive 1 of 3 different modes of TENS .  Methods : Skin and muscle blood flow were monitored noninvasively using a new application of photoplethysmography for 15 minutes of TENS applied at high frequency ( 80 Hz ) and sensory-level intensity and at low frequency ( 2 Hz ) and motor-level intensity and for 15 minutes after stimulation . Subliminal 80-Hz TENS was used as a control . Blood flow was monitored simultaneously on stimulated and nonstimulated shoulders . Results : Blood flow in the trapezius muscle , but not skin blood flow , increased significantly with motor-level 2-Hz TENS , whereas no increase occurred with sensory-level 80-Hz TENS or subliminal 80-Hz TENS . Discussion and Conclusion : Muscle contractions induced by motor-level 2-Hz TENS appear to be a prerequisite for increasing blood flow in the trapezius muscle . However , high stimulation intensity may prevent increased blood flow in the overlying skin Chronic neck pain may increase the transmitter activity of neuropeptides in the upper cervical medulla causing impairment of the blood flow in the local muscle because of a lack of vasodilatatory substances excreted axonally . We have been using a new single-fibre technique for clinical determination of the microcirculation ( LDF ) in the trapezius muscles in relation to electromyography ( EMG ) . This study pertains to the 76 patients ( 46 women and 30 men ) who received a final diagnosis of chronic trapezius myalgia out of a total series of 300 cases with chronic neck pain which had been remitted to the National Insurance Administration Hospital in Tranås , Sweden , because their complaints interfered with their working ability . The purpose was to derive more objective medical information upon which to base rehabilitation . Sixty percent had continuous pain and 40 % had pain after physical effort , or at work . Twenty healthy women volunteered to participate as a normal control group . The right and left trapezius muscles of all individuals were examined simultaneously with laser-Doppler flowmetry ( LDF ) and surface EMG during a fatiguing series of stepwise-increased contractions , each of 1 min duration with 1 min rest in between . The most painful side was compared with the opposite side in all patients and , in the female patients , also with the right shoulder of the healthy control women . The patients showed consistently low local blood flow in the painful side . The difference was statistically significant at low contraction intensities . Muscle tension was somewhat elevated , as evidence d by a slight increase of the rms-EMG that was statistically significant at high contraction intensities . The mean power frequency ( MPF ) of the EMG showed no change . The lowered local blood flow was not explained by a changed intramuscular pressure which is low in the trapezius during ordinary activities that do not normally impair the local blood flow ( Larsson , S-E. , Cai , H. and ( Oberg , P.A. , Microcirculation in the upper trapezius muscle during varying levels of static contraction , fatigue and recovery in healthy women . A study using percutaneous laser-Doppler flowmetry and surface electromyograpy , Eur . J. Appl . Physiol . , 66 ( 1993 ) 483 - 488 ) . We conclude that an impaired regulation of the microcirculation in the local muscle is of central importance in chronic trapezius myalgia , causing nociceptive pain which can be differentiated objective ly from neuralgic neck-shoulder pain by the atraumatic technique described OBJECTIVES Although the local response induced by acupuncture manipulation has been considered to be among the 
    Output:
    
agent
***TASK*** the task is to summarize an input biomedical literature in six sentences 
    ***INPUT*** the input is a biomedical literature 
    ***OUTPUT*** the output is the summary of an input biomedical literature in six sentences 
    ***DOCUMENTATION*** 
    ***EXAMPLES*** 
    Input: In October 2000 the German Federal Committee of Physicians and Health Insurers recommended that special Model Projects on Acupuncture ( “ Modellvorhaben Akupunktur ” ) be developed in order to determine the evidence -based role of acupuncture in the treatment of certain illnesses . This paper presents a summary of the main r and omised controlled trials performed as part of these projects , and the associated economic analyses . Overall the results show that acupuncture  is effective in practice for a range of chronic conditions , and it seems likely to have acceptable cost utility ( at least at a rate of ¢35 per session ) . Sham acupuncture , in the form of minimal off-point needling in a therapeutic context , also appears to be effective , being no different to prophylactic medication in migraine , and superior to guideline -based st and ard care in chronic low back pain . In patients recruited to  acupuncture  trials , the response to treatment does not differ between those that agree to be r and omised and those that do not . This suggests that the results of the pragmatic Acupuncture in Routine Care studies are applicable to patients from the general population who express a preference for  acupuncture . In conclusion ,  acupuncture  appears to be effective in a range of chronic conditions and it seems to have acceptable cost-effectiveness in Western health economic terms . These programmes of research do not confirm the hypothesis that needling at specific points is essential to achieve satisfactory clinical effects of acupuncture . Sham acupuncture , in the form of minimal off-point needling in a therapeutic context , is unlikely to be an inactive placebo . In April 2006 , the German health authorities decided that acupuncture would be included into routine reimbursement by social health insurance funds for chronic low back pain and chronic osteoarthritis of the knee Needle stimulation ( acupuncture ) has recently been shown to increase blood flow in the tibialis anterior muscle and overlying skin in healthy subjects ( HS ) and patients with fibromyalgia ( FM ) . The aim of the present study was to examine the effect of needle stimulation on local blood flow in the trapezius muscle and overlying skin in HS and two groups of patients suffering from chronic pain in the trapezius muscle , i.e. , FM and work-related trapezius myalgia ( TM ) patients . Two modes of needling , deep muscle stimulation ( Deep ) and subcutaneous needle insertion ( SC ) , were performed at the upper part of the shoulder and blood flow was monitored for 60 min post-stimulation . Blood flow changes were measured non-invasively by using a new application of photoplethysmography .  Increased blood flow in the trapezius muscle and overlying skin was found in all three groups following both Deep and SC . In HS , Deep was superior to SC in increasing skin and muscle blood flow , whereas in FM , SC was as effective as , or even more effective , than Deep . In the severely affected TM patients , no differences were found between the stimuli , and generally , a lesser blood flow response to the stimuli was found . At Deep , the muscle blood flow increase was significantly larger in HS , compared to the two patient groups . Positive correlations were found between muscle blood flow at Deep and pressure pain threshold in the trapezius muscle , neck movement and pain experienced at the stimulation , and negative correlations were found with spontaneous pain-related variables , symptom duration and age , pointing to less favorable results with worsening of symptoms , and to the importance of nociceptor activation in blood flow increase . It was hypothesized that the different patterns of muscle blood flow response to the needling may mirror a state of increased sympathetic activity and a generalized hypersensitivity in the patients . The intensity of stimulation should be taken into consideration when applying local needle stimulation ( acupuncture ) in order to increase the trapezius muscle blood flow in chronic pain conditions In 14 healthy female subjects , the effects of needle stimulation ( acupuncture ) on skin and muscle blood flow were investigated using a non-invasive custom- design ed probe and photoplethysmography ( PPG ) . In r and omised order , 2–7 days apart , three modes of needle stimulation were performed on the anterior aspect of the tibia : superficial insertion ( SF ) , insertion into the anterior tibial muscle ( Mu ) , and insertion into the muscle including manipulation of the needle in order to elicit a distinct sensation of distension , heaviness or numbness ( DeQi ) . Before intervention , the subjects rested for 30 min . After the intervention , the needle was left in situ for 20 min . Blood flow recordings were performed intermittently from 10 min prior to the intervention to the end of the trial . In a fourth session , serving as control , corresponding measurements were performed without any needle stimulation . Area under curve was calculated for 5-min periods prior to and after stimulation , respectively , and for the remaining 15-min period after stimulation . Compared to the control situation , muscle blood flow increased following both Mu and DeQi for 20 min , with the latter being more pronounced for the initial 5 min . Skin blood flow increased for 5 min following DeQi . However , no increase was found following SF . The DeQi stimulation was preceded by higher visual analogue scale ratings of anxiety prior to stimulation , which might have influenced skin blood flow to some extent . The results indicate that the intensity of the needling is of importance , the DeQi stimulation result ing in the most pronounced increase in both skin and muscle blood flow Rapidly repeated imaging of the left middle fingertip skin blood perfusion was performed in 51 healthy volunteers ( mean age±SD : 25.3±7.6 years ) prior to , immediately after and in the early reperfusion phase following introduction of an acupuncture needle at the Neiguan point ( Pe . 6 ) and at a placebo point respectively , using a Laser Doppler Perfusion Imager ( LDPI ) . The average skin perfusion of the fingertip was calculated for each image and used as an indicator of the microvascular response to the acupuncture needle introduction . The results of this r and omised , placebo-controlled , cross-over study showed significant differences ( p≤0.001 ) in the immediate skin blood perfusion response when needling is performed in an acupuncture point ( Neiguan ) and a placebo point , with a more pronounced reduction in skin blood perfusion when needling the acupuncture point . In the early reperfusion phase , however , a substantial increase in skin perfusion was observed that amounted to about 18 % of the level prior to needle introduction , irrespective of the site of needle application . In a single individual it was demonstrated that the vasodilatation following needling in the acupuncture point persisted for a more extended time period . These results suggest that the LDPI technology may be useful in visualising and quantifying the peripheral vascular effects of acupuncture on the microcirculation Although it is widely used , the mechanisms and effects of acupuncture on pain are not completely understood . Recently , increased nitric oxide ( NO ) synthase activity has been found in meridians and acupoints . Because NO is a key regulator of local circulation , and because change in circulation can affect the development and persistence of pain , we propose that acupuncture might regulate NO levels . We studied the effects of acupuncture on local NO levels and circulation in a r and omized , double-blind , crossover study with 20 volunteers , each of whom underwent one session each of real and noninvasive sham acupuncture in a single h and and forearm with a 1-wk interval between treatments . NO concentration in the plasma from the acupunctured arm was significantly increased by 2.8 ± 1.5 μmol/L at 5 min and 2.5 ± 1.4 μmol/L at 60 min after acupuncture . Blood flow in palmar subcutaneous tissue of the acupunctured arm also increased , and this correlated with the NO increase . These changes were not observed in noninvasive sham-acupunctured h and s and forearms . In conclusion , acupuncture increases the NO level in treated regions and thereby increases local circulation . These regulatory effects might contribute to pain relief provided by acupuncture Acupuncture has become a widely used treatment modality in various musculoskeletal pain conditions . Acupuncture is also shown to enhance blood flow and recovery in surgical flaps . The mechanisms behind the effect on blood flow were suggested to rely on vasoactive substances , such as calcitonin gene-related peptide , released from nociceptors by the needle stimulation . In a previous study on healthy subjects , one needle stimulation into the anterior tibial muscle was shown to increase both skin and muscle blood flow . The aim of this study was to examine the effect of needle stimulation on local blood flow in the anterior tibial muscle and overlying skin in patients suffering from a widespread chronic pain condition . Fifteen patients with fibromyalgia ( FM ) participated in the study . Two modes of needling , deep muscle stimulation and subcutaneous needle insertion were performed at the upper anterior aspect of the tibia , i.e. , in an area without focal pathology or ongoing pain in these patients . Blood flow changes were assessed non-invasively by photoplethysmography ( PPG ) . The results of the present study were partly similar to those earlier found at a corresponding site in healthy female subjects , i.e. , deep muscle stimulation result ed in larger increase in skin blood flow ( mean ( SE ) ) : 62.4 % ( 13.0 ) and muscle blood flow : 93.1 % ( 18.6 ) , compared to baseline , than did subcutaneous insertion ( mean ( SE ) skin blood flow increase : 26.4 % ( 6.2 ) ; muscle blood flow increase : 46.1 % ( 10.2 ) ) . However , in FM patients subcutaneous needle insertion was followed by a significant increase in both skin and muscle blood flow , in contrast to findings in healthy subjects where no significant blood flow increase was found following the subcutaneous needling . The different results of subcutaneous needling between the groups ( skin blood flow : p=0.008 ; muscle blood flow : p=0.027 ) may be related to a greater sensitivity to pain and other somatosensory input in FM Background and Purpose : Various research ers have studied the effects of transcutaneous electrical nerve stimulation ( TENS ) on hemodynamics . The purpose of this study was to examine the effects of TENS on local blood flow in the trapezius muscle and overlying skin . Subjects : Thirty-three women who were healthy , aged 25 to 55 years , were r and omly assigned to receive 1 of 3 different modes of TENS .  Methods : Skin and muscle blood flow were monitored noninvasively using a new application of photoplethysmography for 15 minutes of TENS applied at high frequency ( 80 Hz ) and sensory-level intensity and at low frequency ( 2 Hz ) and motor-level intensity and for 15 minutes after stimulation . Subliminal 80-Hz TENS was used as a control . Blood flow was monitored simultaneously on stimulated and nonstimulated shoulders . Results : Blood flow in the trapezius muscle , but not skin blood flow , increased significantly with motor-level 2-Hz TENS , whereas no increase occurred with sensory-level 80-Hz TENS or subliminal 80-Hz TENS . Discussion and Conclusion : Muscle contractions induced by motor-level 2-Hz TENS appear to be a prerequisite for increasing blood flow in the trapezius muscle . However , high stimulation intensity may prevent increased blood flow in the overlying skin Chronic neck pain may increase the transmitter activity of neuropeptides in the upper cervical medulla causing impairment of the blood flow in the local muscle because of a lack of vasodilatatory substances excreted axonally . We have been using a new single-fibre technique for clinical determination of the microcirculation ( LDF ) in the trapezius muscles in relation to electromyography ( EMG ) . This study pertains to the 76 patients ( 46 women and 30 men ) who received a final diagnosis of chronic trapezius myalgia out of a total series of 300 cases with chronic neck pain which had been remitted to the National Insurance Administration Hospital in Tranås , Sweden , because their complaints interfered with their working ability . The purpose was to derive more objective medical information upon which to base rehabilitation . Sixty percent had continuous pain and 40 % had pain after physical effort , or at work . Twenty healthy women volunteered to participate as a normal control group . The right and left trapezius muscles of all individuals were examined simultaneously with laser-Doppler flowmetry ( LDF ) and surface EMG during a fatiguing series of stepwise-increased contractions , each of 1 min duration with 1 min rest in between . The most painful side was compared with the opposite side in all patients and , in the female patients , also with the right shoulder of the healthy control women . The patients showed consistently low local blood flow in the painful side . The difference was statistically significant at low contraction intensities . Muscle tension was somewhat elevated , as evidence d by a slight increase of the rms-EMG that was statistically significant at high contraction intensities . The mean power frequency ( MPF ) of the EMG showed no change . The lowered local blood flow was not explained by a changed intramuscular pressure which is low in the trapezius during ordinary activities that do not normally impair the local blood flow ( Larsson , S-E. , Cai , H. and ( Oberg , P.A. , Microcirculation in the upper trapezius muscle during varying levels of static contraction , fatigue and recovery in healthy women . A study using percutaneous laser-Doppler flowmetry and surface electromyograpy , Eur . J. Appl . Physiol . , 66 ( 1993 ) 483 - 488 ) . We conclude that an impaired regulation of the microcirculation in the local muscle is of central importance in chronic trapezius myalgia , causing nociceptive pain which can be differentiated objective ly from neuralgic neck-shoulder pain by the atraumatic technique described OBJECTIVES Although the local response induced by acupuncture manipulation has been considered to be among the 
    Output:
    