Procedures and measurement properties of the 6-min step test: A systematic review with clinical recommendations.

OBJECTIVE: To provide information regarding the procedures, safety, tolerability, and measurement properties of the 6-min step test. DATA SOURCES: MEDLINE, EMBASE, CINAHL, and SPORTDiscus (from inception until January 2024). REVIEW METHODS: Studies that examined adults with acute or chronic diseases, and outcomes related to procedures, safety, tolerability, or measurement properties of the 6-min step test were included. Outcome data were summarized and combined in meta-analyses. The quality of included studies was assessed by the Consensus-based Standards for the selection of health Measurement Instruments checklist, and the quality of evidence was determined according to the Grading of Recommendations Assessment, Development, and Evaluation system. RESULTS: Fourteen studies, involving 847 participants, were included. All studies performed the 6-min step test in 6 min; however, some studies varied the step height and the use of upper limb support. The test appears to be safe and well tolerated by individuals. Moderate- to high-quality evidence demonstrated appropriate results for test-retest reliability (4 studies; Intraclass correlation coefficient 0.96; 95% CI 0.91-0.98; n = 125), criterion validity (4 studies; r = 0.53; 95% CI 0.30-0.71; n = 307), and construct validity (4 studies; r = 0.63; 95% CI 0.52-0.73; n = 233). CONCLUSION: This review provides recommendations for applying the 6-min step test in clinical and research settings. No adverse events were reported, and the test appears to be well tolerated. Adequate results were found for test-retest reliability, criterion validity, and construct validity. REVIEW REGISTRATION: PROSPERO (CRD42022347744).

Manual Therapy Applied to the Cervial Joint Reduces Pain and Improves Jaw Function in Individuals with Temporomandibular Disorders: A Systematic Review on Manual Therapy for Orofacial Disorders.

AIMS: To examine the effect of manual therapy applied to the cervical joint for reducing pain and improving mouth opening and jaw function in people with TMDs. METHODS: A systematic review of randomized controlled trials was performed. Participants were adults diagnosed with TMDs. The experimental intervention was manual therapy applied to the cervical joint compared to no intervention/placebo. Outcome data relating to orofacial pain intensity, pressure pain threshold (PPT), maximum mouth opening, and jaw function were extracted and combined in meta-analyses. RESULTS: The review included five trials involving 213 participants, of which 90% were women. Manual therapy applied to the cervical joint decreased orofacial pain (mean difference: -1.8 cm; 95% CI: -2.8 to -0.9) and improved PPT (mean difference: 0.64 kg/cm2; 95% CI: 0.02 to 1.26) and jaw function (standardized mean difference: 0.65; 95% CI: 0.3 to 1.0). CONCLUSION: Manual therapy applied to the cervical joint had short-term benefits for reducing pain intensity and improving jaw function in women with TMDs. Further studies are needed to improve the quality of the evidence and to investigate the maintenance of benefits beyond the intervention period.

Aliskiren and l-arginine treatments restore depressed baroreflex sensitivity and decrease oxidative stress in renovascular hypertension rats.

Renovascular hypertension is characterized by increased angiotensin II and oxidative stress, and by endothelial dysfunction. The purpose of this study was to test whether the administration of aliskiren (ALSK) and l-arginine (l-ARG) would restore impaired baroreflex sensitivity and reduce oxidative stress in a rat renovascular hypertension model. Hypertension was induced by clipping the left renal artery, and the following five groups were created: SHAM; two-kidney, 1-clip (2K1C); 2K1C plus ALSK (ALSK); 2K1C plus l-ARG (l-ARG); and 2K1C plus ALSK+l-ARG (ALSK+l-ARG). After 21 days of treatment, only the ALSK+l-ARG group was effective in normalizing the arterial pressure (108.8±2.8 mm Hg). The l-ARG and ALSK+l-ARG groups did not show hypertrophy of the left ventricle. All the treatments restored the depressed baroreflex sensitivity to values found in the SHAM group. Acute administration of TEMPOL restored the depressed baroreflex sensitivity in the 2K1C group to values that resembled those presented by the other groups. All treatments were effective for an increase in the antioxidant pathway and reduction in the oxidative pathway. In conclusion, the treatment with ALSK or l-ARG reduced oxidative stress and restored reduced baroreflex sensitivity in renovascular hypertension. In addition, the treatments were able to normalize blood pressure and reverse left ventricular hypertrophy when used in combination.

Combined Aliskiren and L-arginine treatment reverses renovascular hypertension in an animal model.

Renovascular hypertension is characterized by increased renal sympathetic activity, angiotensin II and by endothelial dysfunction. The purpose of this study was to determine the role of renal sympathetic nerve activity (RSNA) in mediating the anti-hypertensive effects of aliskiren (ALSK) and L-arginine (L-ARG) in a rat renovascular hypertension model. Hypertension was induced by clipping the right renal artery, and the following five groups were divided: SHAM operated; 2-kidney, 1-clip (2K1C); 2K1C plus ALSK; 2K1C plus L-ARG; and 2K1C plus ALSK+ L-ARG. The systolic blood pressure (SBP) of 2K1C rats increased from 114.4±5.2 to 204±12.7 mm Hg (P<0.05) and was only reduced by ALSK+L-ARG treatment (138.4±4.37 mm Hg). The 2K1C hypertension increased the baseline RSNA (SHAM: 62.4±6.39 vs. 2K1C: 97.4±8.43%). L-ARG or ALSK+L-ARG treatment significantly decreased baseline RSNA (2K1C L-ARG:70.7±2.39; 2K1C ALSK+L-ARG: 69.3±4.23%), but ALSK treatment alone did not (2K1C ALSK: 84.2±2.5%). Urinary water, Na(+), Cl(-) and urea excretion were similar in the 2K1C L-ARG, 2K1C ALSK+L-ARG and SHAM groups. The combination of ALSK+L-ARG restored urine flow and increased the glomerular filtration rate. The nNOS expression in the non clipped kidney was significantly increased in 2K1C ALSK+L-ARG rats. In conclusion, combined ALSK+L-ARG treatment normalizes SBP and prevents renal dysfunction in 2K1C hypertensive rats.

Role of renal nerves in the treatment of renovascular hypertensive rats with L-arginine.

The purpose was to determine the role of renal nerves in mediating the effects of antihypertensive treatment with L-arginine in a renovascular hypertension model. The 2K1C (two-kidney one-clip model) hypertensive rats were submitted to bilateral surgical-pharmacological renal denervation. The animals were subdivided into six experimental groups: normotensive control rats (SHAM), 2K1C rats, 2K1C rats treated with L-arginine (2K1C + L-arg), denervated normotensive (DN) rats, denervated 2K1C (2K1C + DN) rats, and denervated 2K1C + L-arg (2K1C + DN + L-arg) rats. Arterial blood pressure, water intake, urine volume, and sodium excretion were measured. The 2K1C rats exhibited an increase in the mean arterial pressure (MAP) (from 106 ± 3 to 183 ± 5.8 mmHg, P < 0.01), whereas L-arg treatment induced a reduction in the MAP (143 ± 3.4 mmHg) without lowering it to the control level. Renal nerve denervation reduced the MAP to normotensive levels in 2K1C rats with or without chronic L-arg treatment. L-arg and denervation induced increases in water intake and urine volume, and L-arg caused a significant natriuretic effect. Our results suggest that renal sympathetic activity participates in the genesis and the maintenance of the hypertension and also demonstrate that treatment with L-arg alone is incapable of normalizing the MAP and that the effect of such treatment is not additive with the effect of kidney denervation.