***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: Background Pain reduction can be achieved by lowering proinflammatory cytokine levels in the blood . Transcutaneous electrical nerve stimulation ( TENS ) is a non-invasive physiotherapeutic re source for pain management , but evidence on the effectiveness of this device at reducing proinflammatory cytokines in the blood is unclear . This study systematic ally review s the literature on the effect of TENS on proinflammatory cytokines . Methods A systematic review protocol was developed based on search es of articles in six electronic data bases and references of retrieved articles , contact with authors , and repositories of clinical trials . Eligibility criteria : publication in peer- review ed journals , r and omized clinical trials , use of TENS in the experimental group , and pre- and post- measurements of proinflammatory cytokines in the blood . Selection of the studies and extraction of the data will be carried out by two review ers independently . Characteristics of the study , participants , interventions and outcomes were extracted and described . Assessment s were performed on the risk of bias , level of evidence and the size of the intervention effect in the studies , according to GRADE guidelines and the Cochrane H and book for Systematic Review s. Clinical and statistical assessment s compared the effects of the interventions ( meta- analysis ) , taking into consideration any influencing characteristics of the studies ( e.g. , methods and application sites ) . Discussion We anticipate that this review will strengthen evidence -based knowledge of the effect of TENS on proinflammatory cytokines and , as a result , direct new studies to benefit patients with specific pathologies . Systematic review registration PROSPERO , CRD42017060379 Background : Chronic pelvic pain is prevalent in 2 % of women population globally . The etiology is multifactorial . Even in the absence of pelvic pathology , there is a subgroup of women who do not respond to analgesic and anti-inflammatory therapy . Chronic pelvic pain can be inhibited by direct inhibition of impulses in the preganglionic afferent neuron by closing the hypothetical gate in the dorsal horn of the spinal cord . Transcutaneous electrical nerve stimulation ( TENS ) is based on the gate control theory of abolishing the painful stimuli by providing simultaneous inputs in larger myelinated nerve fibers . Aims and Objectives : This study was design ed to assess the effectiveness and safety of TENS in idiopathic chronic pelvic pain . Methods : It is a prospect i ve , experimental study to evaluate the effectiveness of TENS versus placebo in reducing pain severity in chronic pelvic pain ( G1 = 30 , G2 = 32 , G3 = 30 , and G0 = 30 ) . Patients with chronic pelvic pain due to benign lesions of genital tract , gastrointestinal , and renal disorders were excluded from the study after performing an ultrasound study of abdomen and pelvis . Ten treatment sessions ( 5 sessions/week ) of 30 min were conducted . Observations and Results : There was a significant improvement in pain scores in TENS group as compared with control group , and two patients were completely pain free following TENS therapy . Conclusion : In women patients with idiopathic chronic pelvic pain , TENS can be a useful intervention . TENS units are safe , economical , and easily commercially available In the GRADE approach , r and omized trials start as high- quality evidence and observational studies as low- quality evidence , but both can be rated down if most of the relevant evidence comes from studies that suffer from a high risk of bias . Well-established limitations of r and omized trials include failure to conceal allocation , failure to blind , loss to follow-up , and failure to appropriately consider the intention-to-treat principle . More recently recognized limitations include stopping early for apparent benefit and selective reporting of outcomes according to the results . Key limitations of observational studies include use of inappropriate controls and failure to adequately adjust for prognostic imbalance . Risk of bias may vary across outcomes ( e.g. , loss to follow-up may be far less for all-cause mortality than for quality of life ) , a consideration that many systematic review s ignore . In deciding whether to rate down for risk of bias -- whether for r and omized trials or observational studies -- authors should not take an approach that averages across studies . Rather , for any individual outcome , when there are some studies with a high risk , and some with a low risk of bias , they should consider including only the studies with a lower risk of bias OBJECTIVE To observe the effect of transcutaneous acupoint electrical stimulation ( TAES ) on plasma ET , CGRP and serum IL-6 , S100beta during craniotomy . METHODS Fifty patients scheduled for neurosurgery were r and omly divided into TAES group ( n=25 ) and control group ( n=25 ) . TAES ( 2/100 Hz , 8 - 12 mA ) of bilateral Hegu ( LI 4)-Quchi ( LI 11 ) , Zusanli ( ST 36)-Sanyinjiao ( SP 6 ) was administrated for patients of TAES group starting 30 min before anesthesia till the end of the operation . Anesthesia of the patients was maintained with sevoflurane inhalation and intermittent intravenous injection of boluses of sulfenany and vecurnium bromide . Jugular venous blood sample s were taken at preanesthesia ( T0 ) , 1 hour after craniotomy ( T1 ) , closure complete ( T2 ) , 24 hours ( T3 ) and 48 hours ( T4 ) after operation respectively for detecting contents of plasma endothelin ( ET ) , calcitonin gene-related peptide ( CGRP ) and serum interleukin (IL)-6 , S100beta with radioimmunoassay and enzyme linked immunosorbent assay separately . RESULTS Compared with control group , plasma ET at T2 , serum IL-6 at T1 S100beta at T1 and T4 in TAES group all decreased significantly ( P < 0.01 , 0.05 ) , while serum IL-6 at T3 increased remarkably ( P < 0.05 ) . It suggests that after TAES , CGRP/ET was improved , favoring cerebral microcirculation to reduce surgery-induced cerebral injury . There were no significant differences between two groups at different time courses in plasma CGRP concentrations ( P > 0.05 ) . CONCLUSION TAES can regulate plasma CGRP/ET and serum IL-6 , lower serum S100beta level , which may contribute to its effect in relieving craniotomy-induced brain injury Objective To observe the effect of electro-acupuncture ( EA ) on tumor necrosis factor-α ( TNF-α ) and vascular endothelial growth factor ( VEGF ) in peripheral blood and joint synovia in patients with rheumatoid arthritis ( RA ) to verify the clinical efficacy of EA . Methods Adopting r and omized controlled principle , the 63 RA patients enrolled were assigned to two groups , the 32 patients in the EA group were treated with EA , and the 31 patients in the simple needling ( SN ) group treated with simple needling . According to the integral-local combining method , the acupoints were selected mainly from yang-meridian and local Ashi points ( pain-point ) . EA or SN was applied every other day , 10 times as a course , and each patient received a total of 3 courses of treatment . Results Blood and synovial levels of TNF-α and VEGF were reduced significantly after treatment in both groups . The lowering ( absolute value and difference value ) of TNF-α as well as the absolute value of VEGF , either in blood or in synovia , were similar in the two groups ( P>0.05 ) ; but the lowering of VEGF after treatment was more significant in the EA group than that in the SN group ( P<0.05 ) . Conclusion EA could effectively lower the contents of TNF-α and VEGF in peripheral blood and joint synovia to improve the internal environment for genesis and development of RA , so as to enhance the clinical therapeutic effectiveness Background The postoperative period is associated with increased production of proinflammatory cytokines , which are known to augment pain sensitivity , among other effects . In a previous study , the authors found that patients treated with patient-controlled epidural analgesia ( PCEA )  exhibited attenuated proinflammatory cytokine response in the postoperative period . In the present study , the authors examined whether preemptive analgesia continued with PCEA may further attenuate the proinflammatory cytokine response and reduce pain sensitivity in the postoperative period . They compared cytokine production in two groups of patients , one receiving  PCEA  , the other receiving preemptive epidural analgesia continued by PCEA . Methods Female patients hospitalized for transabdominal hysterectomy were r and omly assigned to one of two pain management techniques : PCEA or preemptive epidural analgesia followed by PCEA ( PA + PCEA ) . Postoperative pain was assessed using the visual analog scale . Blood sample s were collected before , 24 , 48 , and 72 h following surgery . Production of the following cytokines was assessed ex vivo in stimulated peripheral blood mononuclear cells : interleukin (IL)-1&bgr ; , tumor necrosis factor & agr ; , IL-6 , IL-1ra , IL-10 , and IL-2 . Results Patients of the PA + PCEA group exhibited lower pain scores throughout the 72 h postoperatively , compared with patients of the PCEA group . In patients of the PA + PCEA group in the postoperative period , production of IL-1&bgr ; , IL-6 , IL-1ra , and IL-10 was significantly less elevated , while IL-2 production was significantly less suppressed . Conclusions Proinflammatory cytokines are key mediators of illness symptoms , including hyperalgesia . The present results suggest that preemptive epidural analgesia is associated with reduced postoperative pain and attenuated production of proinflammatory cytokines OBJECTIVE To explore the mechanism of electroacupuncture on rheumatoid arthritis ( RA ) . METHODS In a r and omized and controlled trial , sixty-three cases with RA were r and omly divided into an electroacupuncture group ( n = 32 ) and a simple acupuncture group ( n = 31 ) . Baihui ( GV 20 ) , Fengchi ( GB 20 ) , Quchi ( LI 11 ) , Waiguan ( TE 5 ) , Guanyuan ( CV 4 ) and Zusanli ( ST 36 ) were selected by coordination method combined whole and local acupoints . The electroacupuncture group was treated with electroacupuncture at the local acupoints near painful joints , continuous wave , retaining needle for 30 minutes , and then electroacupuncture at Back-shu acupoints , retaining needle for 15 minutes , and the simple acupuncture group was treated with the same acupoints selection and acupuncture manipulation without electroacupuncture apparatus . They were all treated once every other day for 20 days as one course . After 3 courses , changes of interleukins in peripheral blood and joint fluid of patients were observed . RESULTS Both of electroacupuncture and simple acupuncture had significant effect on IL-1 , IL-4 , IL-6 and IL-10 in peripheral blood and joint fluid of patients with RA ( P < 0.01 , P < 0.05 ) . But after electroacupuncture , the absolute value and improvement value of decreasing IL-1 in peripheral blood and joint fluid were super than those of simple acupuncture ( all P < 0.05 ) , and of IL-4 in joint fluid was super than that after simple acupuncture ( P < 0.05 ) , and of IL-6 and the absolute value of decreasing IL-10 were almost the same after both treatment ( all P > 0.05 ) , and after electroacupuncture , the improvement value of IL-10 in peripheral blood and joint fluid were super than those after simple acupuncture ( both P < 0.05 ) . CONCLUSION Electroacupuncture can effectively decrease the proinflammatory cytokine of IL-1 and IL-6 and increase the inhibition cytokine of IL-4 and IL-10 and improve the internal environment of occurrence and progression of RA This study examined the effect of transcutaneous electrical nerve stimulation applied over acupoints ( Acu-TENS ) on forced expiratory volume , in patients with asthma , after exercise . Thirty subjects were r and omly assigned to three groups . Group 1 received Acu-TENS over acupuncture points Lieque and Dingchuan for 45 min prior to a symptom-limited treadmill exercise test . Group 2 had Acu-TENS similarly applied prior to and throughout the exercise test . Group 3 mimicked Group 1 but without any electrical output from the device . Forced expiratory volume in one second ( FEV(1 ) ) and forced vital capacity ( FVC ) were recorded before , immediately after and at 20-min intervals post-exercise for 1h . Immediately after exercise , FEV(1 ) and FVC rose in Group 2 ( p=0.015 ) , but decreased in Group 1 and more so in Group 3 . The differences became even more marked at 20 , 40 and 60 min . Adjunctive Acu-TENS therapy appears to reduce decline of FEV(1 ) following exercise training in patients with asthma OBJECTIVES Transcutaneous electrical nerve stimulation ( TENS ) has been used to control post-thoracotomy pain with contrasting results . We aim ed to assess the efficacy of TENS on post-thoracotomy pain in relation of four criterion measurements as : ( i ) cytokines ; ( ii ) pain ; ( iii ) respiratory function and ( iv ) intake of narcotic medication . METHODS Between January 2008 and October 2010 , 58 patients 
    Output:
    
It was observed through the meta- analysis synthesis measures that there were statistically significant differences following the use of TENS to reduce the general group of cytokines .
When grouped by chronic disease , by postoperative setting s , or by individual studies in the case of IL-6 , it was observed that the significant reduction of cytokines related to the use of TENS was maintained .
The use of TENS reduced the blood levels of proinflammatory cytokines ( we observed a protective factor of TENS in relation to inflammation ) .