Mitigating probe pulse deformation in Raman amplification in OTDR fiber sensing systems.

We report the numerical and experimental study of probe pulse deformation in a forward-pumped distributed Raman amplifier on a 40-km standard single mode fiber. Distributed Raman amplification can improve the range of OTDR-based sensing systems, but it could result in pulse deformation. A smaller Raman gain coefficient can be used to mitigate pulse deformation. The sensing performance can still be maintained by compensating for the decrease in the Raman gain coefficient by increasing the pump power. The tunability of the Raman gain coefficient and pump power levels are predicted while keeping the probe power below the modulation instability limit.

Application of Lever's EL Parameter Scale toward Fe(II)/Fe(III) versus Pc(2-)/Pc(1-) Oxidation Process Crossover Point in Axially Coordinated Iron(II) Phthalocyanine Complexes.

The electronic structures and, particularly, the nature of the HOMO in a series of PcFeL2, PcFeL'L″, and [PcFeX2]2- complexes (Pc = phthalocyaninato(2-) ligand; L = NH3, n-BuNH2, imidazole (Im), pyridine (Py), PMe3, PBu3, t-BuNC, P(OBu)3, and DMSO; L' = CO; L″ = NH3 or n-BuNH2; X = NCO-, NCS-, CN-, imidazolate (Im-), or 1,2,4-triazolate(Tz-)) were probed by electrochemical, spectroelectrochemical, and chemical oxidation as well as theoretical (density functional theory, DFT) studies. In general, energies of the metal-centered occupied orbitals in various six-coordinate iron phthalocyanine complexes correlate well with Lever Electrochemical Parameter EL and intercross the phthalocyanine-centered a1u orbital in several compounds with moderate-to-strong π-accepting axial ligands. In these cases, an oxidation of the phthalocyanine macrocycle (Pc(2-)/Pc(1-)) rather than the central metal ion (Fe(II)/Fe(III)) was theoretically predicted and experimentally confirmed.

Case Report: Infection With SARS-CoV-2 in the Presence of High Levels of Vaccine-Induced Neutralizing Antibody Responses.

We present a case of SARS-CoV-2 B.1. 525 infection in a healthcare worker despite the presence of highly neutralizing, multivariant-specific antibodies 7 weeks after full vaccination with the mRNA vaccine BNT162b2. We show that the virus replicated to high levels in the upper respiratory tract over the course of several days in the presence of strong antibody responses. The virus was readily propagatable in vitro, demonstrating the potential to transmit to others, bolstered by the fact that several household members were equally infected. This highlights the importance of protective measures even in vaccinated individuals.

Detectable SARS-CoV-2 RNAemia in Critically Ill Patients, but Not in Mild and Asymptomatic Infections.

BACKGROUND: The SARS-CoV-2 pandemic has challenged many of our current routine practices in the treatment and care of patients. Given the critical importance of blood donation and transfusion we analyzed 92 blood samples of individuals infected with SARS-CoV-2 stratified by symptoms. STUDY DESIGN AND METHODS: We therefore tested blood samples for SARS-CoV-2 via RT-PCR targeting the E gene. In addition, we tested each blood sample for anti-SARS-CoV-2 IgG antibodies via ELISA and performed plaque reduction neutralization tests. RESULTS: SARS-CoV-2 RNA was absent in the blood of mild to asymptomatic patients (57 individuals) and only detectable in individuals with severe COVID-19 who were admitted to the intensive care unit (35 individuals) (n = 6/92 [6.5%]; p = 0.023 Fisher's exact test). Interestingly, anti-spike IgG antibodies were not significantly higher in intensive care unit patients compared to mild patients, but we found that their neutralizing capacity was disproportionately increased (p < 0.001). CONCLUSION: Our observations support the hypothesis that there are no potential hazards from blood or plasma transfusion of SARS-CoV-2-positive individuals with mild flu-like symptoms and more importantly of asymptomatic individuals.

SARS-CoV-2 seroconversions and chains of infection in healthcare professionals in a German maximum care provider (The CoSHeP study).

INTRODUCTION: The CoSHeP study provides novel data on SARS-CoV-2 seroconversion rates in healthcare professionals (HP) at risk at the University Hospital Bonn, a maximum healthcare provider in a region of 900.000 inhabitants. METHODS: Single-center, longitudinal observational study investigating rate of SARS-CoV-2 IgG seroconversion in HP at 2 time-points. SARS-CoV-2 IgG was measured with Roche Elecsys Anti-SARS-CoV-2 assay. RESULTS: Overall, 150 HP were included. Median age was 35 (range: 19-68). Main operational areas were intensive care unit (53%, n = 80), emergency room (31%, n = 46), and infectious disease department (16%, n = 24). SARS-CoV-2-IgG was detected in 5 participants (3%) at inclusion in May/June 2020, and in another 11 participants at follow-up (December 2020/ January 2021). Of the 16 seropositive participants, 14 had already known their SARS-CoV-2 infection because they had performed a PCR-test previously triggered by symptoms. Trailing chains of infection by self-assessment, 31% (n = 5) of infections were acquired through private contacts, 25% (n = 4) most likely through semi-private contacts during work. 13% (n = 2) were assumed to result through contact with contagious patients, further trailing was unsuccessful in 31% (n = 5). All five participants positive for SARS-CoV-2 IgG at inclusion remained positive with a median of 7 months after infection. DISCUSSION: Frontline HP caring for hospitalized patients with COVID-19 are at higher risk of SARS-CoV-2 infections. Noteworthy, based upon identified chains of infection most of the infections were acquired in private environment and semi-private contacts during work. The low rate of infection through infectious patients reveals that professional hygiene standards are effective in preventing SARS-CoV-2 infections in HP. Persisting SARS-CoV-2-IgG might indicate longer lasting immunity supporting prioritization of negative HP for vaccination.

Ad hoc laboratory-based surveillance of SARS-CoV-2 by real-time RT-PCR using minipools of RNA prepared from routine respiratory samples.

BACKGROUND: A novel coronavirus, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), emerged in China in late 2019 and subsequently caused a pandemic. Surveillance is important to better appreciate this evolving pandemic and to longitudinally monitor the effectiveness of public health measures. OBJECTIVES: We aimed to provide a rapid, easy to establish and costeffective laboratory-based surveillance tool for SARS-CoV-2. STUDY DESIGN: We used minipools of RNA prepared from nucleic acid extractions of routine respiratory samples. We technically validated the assay and distributed the protocol within an informal network of five German university laboratories. RESULTS: We tested a total of 70 minipools resembling 700 samples shortly before the upsurge of cases in Germany from 17.02.2020 to 10.03.2020. One minipool reacted positive and after resolution one individual sample tested SARS-CoV-2 positive. This sample was from a hospitalized patient not suspected of having contracted SARS-CoV-2. CONCLUSIONS: Our approach of a laboratory-based surveillance for SARSCoV-2 using minipools proved its concept is easily adaptable and resource-saving. It might assist not only public health laboratories in SARS-CoV-2 surveillance.

Phospholipidation of nuclear proteins by the human papillomavirus E6 oncoprotein: implication in carcinogenesis.

Phospholipids regulate numerous cellular functions and their deregulation is known to be associated with cancer development. Here, we show for the first time that expression of the E6 oncoprotein of human papillomavirus type 8 (HPV8) leads to a profound increase in nuclear phosphatidylinositol-4,5-bisphosphate (PI(4,5)P2) lipid levels in monolayer cultures, that led to an aberrant phospholipidation of cellular proteins. Elevated PI(4,5)P2 levels in organotypic skin cultures, skin tumors of K14-HPV8-E6 transgenic mice as well as HPV8 positive skin carcinomas highly suggest a decisive role of PI(4,5)P2 in HPV associated squamous-cell-carcinoma development. Furthermore, mass-spectrometric analysis confirmed an increase of PI(4,5)P2, which was characterized by a shift in the distribution of lipid species. PI(4,5)P2 upregulation was independent of E6 interference with MAML1. However, E6 does interfere with the PI(4,5)P2 metabolic pathway by upregulation of phosphatidylinositol-4-phosphate-5-kinase type I and phosphatidylinositol-5-phosphate 4-kinase type II as well as the binding to 5'-phosphatase OCRL and phosphatidylinositol. All of these mechanisms combined may contribute to PI(4,5)P2 elevation in E6 positive cells. The identification of CAND1 and SND1 - two proteins known to be involved in carcinogenic processes - were significantly stronger phospholipidized in the presence of E6. In conclusion we provide evidence that the modulation of the PI(4,5)P2 metabolism is a novel oncogenic mechanism relevant for HPV-induced carcinogenesis.

Noninvasive, Multimodality Approach to Treating Plantar Fasciitis: A Case Study.

Plantar fasciitis, also referred to as plantar heel pain, is a common foot pathology among runners and other athletes. The clinical guidelines of the 2014 Orthopedic Section of the American Physical Therapy Association states, noninvasive therapies including manual therapy, stretching, taping, foot orthoses, and night splints are recommended as primary interventions. Recent studies suggest acupuncture may be an effective treatment compared to standard treatment for long-term relief. This case study reports the effects of a multimodality approach including massage, gua sha, bleeding, acupuncture, and moxibustion to treat acute plantar heel pain.

HPV8-E6 Interferes with Syntenin-2 Expression through Deregulation of Differentiation, Methylation and Phosphatidylinositide-Kinase Dependent Mechanisms.

The E6 oncoproteins of high-risk human papillomaviruses (HPV) of genus alpha contain a short peptide sequence at the carboxy-terminus, the PDZ binding domain, with which they interact with the corresponding PDZ domain of cellular proteins. Interestingly, E6 proteins from papillomaviruses of genus beta (betaPV) do not encode a comparable PDZ binding domain. Irrespective of this fact, we previously showed that the E6 protein of HPV8 (betaPV type) could circumvent this deficit by targeting the PDZ protein Syntenin-2 through transcriptional repression (Lazic et al., 2012). Despite its high binding affinity to phosphatidylinositol-4,5-bisphosphate (PI(4,5)P2), very little is known about Syntenin-2. This study aimed to extend the knowledge on Syntenin-2 and how its expression is controlled. We now identified that Syntenin-2 is expressed at high levels in differentiating and in lower amounts in keratinocytes cultured in serum-free media containing low calcium concentration. HPV8-E6 led to a further reduction of Syntenin-2 expression only in cells cultured in low calcium. In the skin of patients suffering from Epidermodysplasia verruciformis, who are predisposed to betaPV infection, Syntenin-2 was expressed in differentiating keratinocytes of non-lesional skin, but was absent in virus positive squamous tumors. Using 5-Aza-2'-deoxycytidine, which causes DNA demethylation, Syntenin-2 transcription was profoundly activated and fully restored in the absence and presence of HPV8-E6, implicating that E6 mediated repression of Syntenin-2 transcription is due to promoter hypermethylation. Since Syntenin-2 binds to PI(4,5)P2, we further tested whether the PI(4,5)P2 metabolic pathway might govern Syntenin-2 expression. PI(4,5)P2 is generated by the activity of phosphatidylinositol-4-phosphate-5-kinase type I (PIP5KI) or phosphatidylinositol-5-phosphate-4-kinase type II (PIP4KII) isoforms α, ß and γ. Phosphatidylinositide kinases have recently been identified as regulators of gene transcription. Surprisingly, transfection of siRNAs directed against PIP5KI and PIP4KII resulted in higher Syntenin-2 expression with the highest effect mediated by siPIP5KIα. HPV8-E6 was able to counteract siPIP4KIIα, siPIP4KIIß and siPIP5KIγ mediated Syntenin-2 re-expression but not siPIP5KIα. Finally, we identified Syntenin-2 as a key factor regulating PIP5KIα expression. Collectively, our data demonstrates that Syntenin-2 is regulated through multiple mechanisms and that downregulation of Syntenin-2 expression may contribute to E6 mediated dedifferentiation of infected skin cells.

Treatment of Chemotherapy-Induced Peripheral Neuropathy in Integrative Oncology: A Survey of Acupuncture and Oriental Medicine Practitioners.

OBJECTIVES: Complementary and alternative medicine is increasingly integrated into cancer care. We sought detail on the treatment of chemotherapy-induced peripheral neuropathy (CIPN) with acupuncture and oriental medicine (AOM) by surveying practitioners at integrative oncology (IO) sites across the United States. DESIGN: Online survey of licensed acupuncturists. SETTING/LOCATION: IO sites in the United States. SUBJECTS: Fifteen licensed acupuncturists who completed the survey between February 2014 and June 2014. OUTCOME MEASURES: Demographics, IO setting characteristics, AOM treatment characteristics, and practitioner-reported outcomes. RESULTS: Respondents reported an average of 31.3 ± 17.2 patients per week, and one-third (10.1 mean; 7.2 standard deviation [SD]) were treated for CIPN. Medical doctors (86.7%) were the most common providers with whom respondents worked. Traditional Chinese medicine style acupuncture was utilized by a majority of respondents (86.7%), and the most commonly used points were local, typically in the hands and feet, such as Ba Feng, Ba Xie, LV3, and LI4. In addition to acupuncture, nutritional advice was the most frequent auxiliary modality provided by respondents (85.7%). On average, respondents provided 12.75 ± 4.17 treatments for CIPN patients, and a majority (53%) reported treating patients once per week. Timing of the treatments relative to chemotherapy infusion was evenly distributed between "1-2 days after infusion" (60%), "at time of infusion" (53.3%), and "1-2 days before infusion" (46.7%). Sixty percent of respondents rated outcomes as "moderately successful with moderate improvement seen." CONCLUSION: This survey provides detail regarding IO sites using acupuncture for CIPN as well as real-world treatment patterns, including common point combinations, visit characteristics, and practitioner-reported outcomes. This information contributes to the emerging evidence on the use of acupuncture to address unmet needs of CIPN patients, and supports the development of best practice guidelines for the treatment of CIPN with acupuncture in the IO setting.

Super-Users at an Acupuncture and Oriental Medicine Teaching Clinic: Demographics and Unique Clinical Characteristics.

OBJECTIVE: The use of acupuncture in the United States has consistently grown over the last two decades, and the National Center for Complementary and Integrative Health has recently called for greater understanding of "real life outcomes and use" by complementary and alternative medicine users. This study assesses the demographics and utilization patterns of "super-users" treated at the Oregon College of Oriental Medicine intern clinic. METHODS: This was a retrospective chart review at the Oregon College of Oriental Medicine (OCOM) intern clinic, a large acupuncture and oriental medicine (AOM) school in Portland, Oregon. Participants were patients who were treated 100+ times at the OCOM between August 6, 2002, and 2012. The outcome measures were demographic and treatment characteristics, including sex, age, chief complaint, income, medication use, and visit patterns. RESULTS: The super-user cohort comprised approximately 1.5% of the total annual patient population and 8% of total visits at the OCOM in any given year, with an average treatment duration of 4 years from visit 1 to visit 100, and a visit frequency of 32 visits per year. Similar to other studies, the super-user cohort consisted predominantly of older, female patients seeking treatment primarily for pain (57.3%). Prescription medication use (45.2%) was also similar to other acupuncture cohorts. In contrast to typical AOM patients, OCOM super-users were older, with 64% being age ≥50 years when initiating treatment, and a majority reported low-income status (92%). CONCLUSIONS: Super-users represent a small yet real subset of AOM patients. They tend to be older, report lower income, and exhibit greater visit frequency than more typical AOM users. The factors motivating AOM super-user behavior may be different from those in other medical domains, notably emergency medicine, and likely include long-term management of chronic pain and other chronic conditions. Future studies into the long-term health outcomes of AOM super-users, as well as the economic impact on other health services, are warranted.

The levels of epithelial anchor proteins ß-catenin and zona occludens-1 are altered by E7 of human papillomaviruses 5 and 8.

Infection with viruses of the genus Betapapillomavirus, ß-human papillomaviruses (ß-HPV), is implicated in the development of non-melanoma skin cancer. This was first evidenced for HPV5 and HPV8 in patients with the skin disease epidermodysplasia verruciformis (EV). The relocalization of the junctional bridging proteins ß-catenin and zona occludens-1 (ZO-1) from the adherens and tight junctions are common processes of the epithelial-mesenchymal transition (EMT) associated with tumour invasion. Here, we report that ß-catenin and ZO-1 are strongly upregulated by the E7 oncoproteins of HPV5 and HPV8 in keratinocytes grown in organotypic skin cultures. Although the membrane-tethered form of ß-catenin was elevated, no signs of ß-catenin activity within the canonical Wnt signalling pathway could be detected. The upregulation of ß-catenin and ZO-1 could also be confirmed in the skin of HPV8 transgenic mice as well as in cutaneous squamous cell carcinomas of EV patients. These data provide the first evidence that ß-catenin and ZO-1 are direct targets of E7 of the oncogenic ß-HPV types 5 and 8. The ability to deregulate these epithelial junction proteins may contribute to the oncogenic potential of these viruses in human skin.

Nontouch biofield therapy: a systematic review of human randomized controlled trials reporting use of only nonphysical contact treatment.

UNLABELLED: OBJECTIVE AND CONTEXT: This review was designed to assess the quality and review the outcomes of randomized controlled trials (RCTs) of biofield therapies (external qigong, Healing Touch, Johrei, Reiki, and Therapeutic Touch) that report using only nonphysical touch forms of treatment. RCTs of nonphysical contact biofield therapies have the potential to contribute to an evidence base for health-promoting effects mediated through mechanisms outside the present understanding of biomedicine. METHODS: Articles meeting inclusion criteria were identified from database and reference list searches and evaluated for a range of reporting and design items. Data were extracted to determine the range of protocol parameters and treatment outcomes. The final set of included RCTs were evaluated via a modified 5-item Jadad scale as well as by a set of 20 criteria that included items relevant to the early-phase nature of the trials and to the examination of nonphysical touch biofield therapy interventions. RESULTS: Of 90 RCTs that assessed effectiveness of a biofield therapy in humans, 28 trials involving 1775 participants met additional inclusion criteria (most importantly a clearly reported use of only nonphysical contact treatment). The research designs of these 28 trials revealed marked heterogeneity in regard to condition treated, number and duration of treatments, nature of the control/comparison group, and outcome measures. Finally, 10 trials were excluded on the basis of low quality assessment scores. Twelve of the remaining 18 trials (7 Therapeutic Touch, 3 external qigong, 1 Reiki, and 1 Healing Touch) reported at least one primary outcome with statistically significant beneficial treatment outcomes. CONCLUSIONS: The pilot study nature of essentially all the identified nonphysical contact biofield therapy RCTs, as reflected by low sample sizes alone, precludes drawing robust conclusions. Given this perspective, the finding that two thirds of the higher-scoring trials demonstrated at least partial effectiveness favors a continued research effort, especially in light of the translational value of biofield clinical trials for studies exploring the nature and physiologic basis of biofield healing.

AcuTrials®: an online database of randomized controlled trials and systematic reviews of acupuncture.

BACKGROUND: The growing quantity of Complementary and Alternative Medicine literature requires databases enabled with increasingly powerful search capabilities. To address this need in the area of acupuncture research, a bibliographic database of randomized controlled trials (RCTs) and systematic reviews called AcuTrials® has been developed by the Oregon College of Oriental Medicine. AcuTrials® introduces a comprehensive keyword thesaurus that categorizes details of treatment protocols and research design to an extent not currently available in MEDLINE or other databases. DESCRIPTION: AcuTrials®, which went live in January of 2010 and is updated monthly, currently contains over 1250 articles from more than 300 journals. Articles included are English language RCTs and systematic reviews that report on medical conditions in human subjects treated by needle acupuncture. Study details are indexed by 14 key domains, such as acupuncture style and needling protocol, to create an acupuncture-relevant, searchable keyword catalogue. Keywords follow the National Library of Medicine (NLM) MeSH terminology when possible, and new keywords were created in cases where no appropriate MeSH terms were available. The resulting keyword catalogue enables users to perform sensitive, targeted searches for particular aspects of acupuncture treatment and research design. CONCLUSIONS: AcuTrials® provides an extensive and innovative keyword catalogue of acupuncture research, allowing users to efficiently navigate, locate and assess the evidence base in ways not currently possible with other databases. By providing a more powerful suite of search options, the AcuTrials® database has the potential to enhance the accessibility and quality of acupuncture research.

A prospective patient-centered data collection program at an acupuncture and oriental medicine teaching clinic.

OBJECTIVE: Large-scale patient-reported outcomes research investigating the role of acupuncture and Oriental medicine (AOM) in general practice is limited, despite the growing use of AOM in the United States. This article describes the development and refinement of a prospective, patient-centered outcomes data collection program at an Oriental medicine college and presents demographic and clinical data. SETTING/LOCATION: Individualized acupuncture treatment at the Oregon College of Oriental Medicine teaching clinic in Portland, Oregon. METHODS: A prospective patient-centered data collection program was implemented in 2007 using the Measure Your Medical Outcomes Profile (MYMOP) questionnaire and college-developed demographic and conditions forms. The forms were completed by patients on the first and fifth clinic visit. The program was revised after two years to streamline the data entry process and to include three Patient Reported Outcome Measurement Information System (PROMIS) questionnaires measuring pain, general health, and physical functioning. OUTCOME MEASURES: Outcome measures were patient demographics, chief complaints, MYMOP, and PROMIS data collected at first visit. RESULTS: Demographics were similar to those reported in other AOM settings. The majority of patients were Caucasian females and expressed confidence in acupuncture treatment. The most common chief complaint was joint and muscle pain. Additionally, we found that mean scores at baseline for global physical and mental health and physical functioning were all lower than U.S. averages. In contrast to some studies, we found that the majority of patients had previous experience with acupuncture. CONCLUSIONS: An ongoing, prospective data collection program can be successfully developed and implemented at an AOM college. The program will ultimately provide large-scale, patient-reported outcomes on patients seeking AOM treatment at the student clinic.

Recurrent Pregnancy Loss and Traditional Chinese Medicine.

BACKGROUND: Recurrent pregnancy loss (RPL) can present with coexistent subfertility caused by diminished ovarian reserve (DOR). Recent texts suggest that Traditional Chinese Medicine (TCM) may improve pregnancy outcomes for women with RPL. OBJECTIVE: This article reports the outcome of the treatment of a female of advanced maternal age. She had diagnoses of DOR and RPL. DESIGN SETTING AND PATIENT: This 42-year-old patient with DOR and RPL presented in a private acupuncture practice, located in Bellevue, WA. INTERVENTION: The patient received TCM treatment that involved weekly acupuncture and Chinese herbal therapy from June 2006 to May 2007. MAIN OUTCOME MEASURES: The outcome sought was a live birth after 24 weeks of gestation. RESULTS: After another miscarriage in September 2006, this patient conceived a viable pregnancy in December 2006, after 6 months of treatment. She continued treatment through 20 weeks and delivered a healthy son at 39.5 weeks of gestation. CONCLUSIONS: Subfertile women with RPL may benefit from TCM treatment. More research is needed to examine the safety and effectiveness of TCM as a treatment for RPL.

Diminished Ovarian Reserve, Clomid, and Traditional Chinese Medicine: A Case Study.

BACKGROUND: Infertility caused by diminished ovarian reserve (DOR) can result from an endocrinological imbalance. A rise in follicle stimulating hormone (FSH) and decrease in antral follicle count (AFC) for women age ≤35 can lower pregnancy rates to <5%, and increase miscarriage rates to >75%. Chinese medicine may improve FSH and AFC levels in patients with DOR. It is common for women to seek adjunctive Traditional Chinese Medicine (TCM) treatment with biomedical clomid treatment. OBJECTIVE: This article reports the case of a female with DOR who had completed three multiple, serial clomid cycles from September to December 2005, and for whom clomid failed. DESIGN SETTING AND PATIENT: This is a case study of a 34-year-old patient with a 5-year history of infertility caused by DOR. She was treated in a private practice in Bellevue, WA. INTERVENTION: TCM treatment-including acupuncture and herbal therapy-lasted from from January 2007 to April 2007. MAIN OUTCOME MEASURES: The main outcomes sought were improvements in this patient's reproductive hormone panel, including tests for FSH, estradiol, and AFC levels; in addition a pregnancy outcome was desired. RESULTS: After 4 months of TCM treatment, the patient returned to biomedical care. Pregnancy was not achieved during three more clomid cycles, although she had improvements her levels of FSH (from 14.5 mIU/mL to 8.7 mIU/mL) and AFC (from 10-12 to 16-18 total). After 3 more cycles with clomid, her FSH level increased to 16.8 mIU/mL and her AFC level was <10. CONCLUSIONS: After three failed clomid cycles, a patient with DOR had improved FSH and AFC levels when she received TCM treatment. However, this patient was still unable to conceive although three more clomid cycles were attempted. More research is needed to discern demographically which patients benefit best from multiple, serial clomid interventions. In addition, it is important to investigate more-integrative treatments for patients with DOR, including assisted reproductive techniques, acupuncture, and Chinese herbs.

Construct validity of myotonometric measurements of muscle compliance as a measure of strength.

Myotonometric measurement of muscle compliance represents new technology that quantifies muscle tone. Compliance change during muscle contraction might provide an indirect measure of strength. The purpose of this study was to determine relationships among myotonometric measurements of muscle compliance, surface electromyographic (sEMG) measurements of muscle activation and joint force production during voluntary isometric knee extensions. The level of relationship will contribute to the construct validity of use of muscle compliance as an indirect strength measurement. Thirteen male subjects, mean age 25 +/- 1.5 years, participated. Simultaneous recordings of myotonometric, sEMG of the rectus femoris and isometric knee extension force measurements were taken at rest, during maximal voluntary contraction (MVC), and during 33% and 66% MVC contractions. Relationships among the three measurement procedures were calculated using correlation and regression analyses. Myotonometric measures of muscle compliance, sEMG and force measurements were highly correlated. Myotonometric measurements were best represented by a curvilinear (quadratic) relationship to sEMG (r = 0.82, p < 0.001) and joint force (r = 0.83, p < 0.001). The present experiments establish the construct validity of myotonometric measurements of muscle compliance as an indirect means of quantifying muscle strength and activation levels. This method, therefore, offers a possible alternative for cases in which direct measurement of joint force or sEMG is difficult or inappropriate.