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Plyometric activities use rapid switching from eccentric to concentric contractions to increase speed or force of muscle contractions. Training the stretch-shorten cycle by jumping enhances athletic performance. This study sought optimal box heights athletes could drop from to obtain maximal rebound height. Division-III collegiate football players (n = 55) older than18, weighing no more than 100 kg, and with no lower-extremity injury were the participants. Initial data collected measured height, weight, leg length, age, standing vertical jump, and quadriceps strength. Peak torque and work per repetition were calculated for eccentric and concentric quadriceps activity. Participants completed 3 box drops from each of 4 different box heights as vertical rebound was measured. ANOVA showed rebounds did not differ significantly by box height, nor did rebound from any height differ significantly from standing vertical jump. Little to no correlation (Pearson's r < 0.25) was found between vertical rebound from any height and concentric or eccentric work per repetition or eccentric peak torque. Fair correlation (Pearson's r = 0.29DS0.33) was found between concentric peak torque and vertical rebound from all heights. Leg length correlated moderately (Pearson's r = 0.56DS0.61) with vertical rebound from all heights. Because results indicate greater box drop height is not statistically associated with greater vertical rebounds, using a box height above 0.12 m (the shortest tested here) is likely to increase injury risk without providing any accompanying benefits. The study is limited by the fact that jumping technique was not included as a variable, although clearly technique could be a component in rebounding. [ABSTRACT FROM AUTHOR]

Examines the clinical, radiographical and functional outcomes of knee meniscal repair. Reference to assessments made by the Knee Ligament Standard Evaluation Form; Factors affecting the process of lateral meniscal repairs.

Objectives: Quaternary care centres have an imperative to serve as hospitals of last resort and must also meet professional quality targets. We developed a high-risk committee (HRC) to evaluate cases meeting pre-defined predicted risk cut-offs as a part of an overall quality improvement drive., Methods: We describe the structure, outcomes and effects of the Penn HRC. Using propensity-matching, we investigated whether the committee modifies or screens risk. We used multivariable analysis to examine the impact of unmeasured variables on clinical outcomes in this cohort., Results: Institutional predicted and observed mortality had already been in decline prior to HRC institution in 2017, due to a multi-faceted quality improvement initiative. Between 2017 and 2020, the HRC discussed 205 patients with a median predicted risk of mortality of 10.6% (range 0.4-66%). Coronary artery bypass grafting was the most commonly presented operation. A total of 155 patients underwent operation (risk 10.3%), 12 had surgery deferred for optimization (risk 6%), 50 had surgery declined (risk 11.7%) and 12 patients had a deferred decision for further investigation. Overall 30-day survival was 86% for the entire cohort and 89% for operated patients. A matched analysis of similar patients prior to and following the HRC showed that the HRC did not directly modify outcomes. Most patients had better than expected survival (observed:expected mortality < 1). Predicted risk did not predict 30-day mortality among this high-risk cohort., Conclusions: HRCs serve as an important element in quality improvement by encouraging a thoughtful approach and channelling the collective experience of a group of senior surgeons. It may improve patient selection by identifying a cohort with extremely poor survival, while allowing safe operation with acceptable outcomes among a group with very high operative risk., (© The Author(s) 2022. Published by Oxford University Press on behalf of the European Association for Cardio-Thoracic Surgery.)

Objective: Patients with profound cardiogenic shock may require venoarterial (VA) extracorporeal membrane oxygenation (ECMO) for circulatory support most commonly via the femoral vessels. The rate of cardiac recovery in this population remains low, possibly because peripheral VA-ECMO increases ventricular afterload. Whether direct ventricular unloading in peripheral VA-ECMO enhances cardiac recovery is unknown, but is being more frequently utilized. A randomized trial is warranted to evaluate the clinical effectiveness of percutaneous left ventricle venting to enhance cardiac recovery in the setting of VA-ECMO., Methods: We describe the rationale, design, and initial testing of a randomized controlled trial of VA-ECMO with and without percutaneous left ventricle venting using a percutaneous micro-axial ventricular assist device., Results: This is an ongoing prospective randomized controlled trial in adult patients with primary cardiac failure presenting in cardiogenic shock requiring peripheral VA-ECMO, designed to test the safety and effectiveness of percutaneous left ventricle venting in improving the rate of cardiac recovery., Conclusions: The results of this nonindustry-sponsored trial will provide critical information on whether left ventricle unloading in peripheral VA-ECMO is safe and effective., (© 2021 The Author(s).)

Background: Dry mouth is a frequent complaint of adults worldwide. In those who experience dry mouth, therapeutic options include the use of salivary substitutes and sialogogues., Methods: The authors compared the efficacy and safety of mucoadhesive disks (OraMoist, Axiomedic, Zurich; distributed by Quantum Health, Eugene, Ore.) applied three times daily with those of placebo mucoadhesive disks in a double-masked, randomized, controlled crossover study. The primary end point of interest was within-participant differences in subjective (visual analog scale) ratings of dry mouth according to the New York University Bluestone Mouthfeel Questionnaire. The secondary end point was within-participant differences in salivary flow rates., Results: Twenty-seven participants completed the single-site study. The results showed no significant difference between the two types of mucoadhesive disks, both of which were associated with a statistically significant improvement in the subjective experience of moistness across the 60-minute period after application and compared with baseline measures after two weeks of use. Furthermore, both disks were associated with a statistically significant improvement in salivary flow rates across the 60-minute period after application and compared with baseline measures after one and two weeks of use. The disks were well tolerated, and participants did not report any adverse events., Conclusions: The mucoadhesive disks used in this study were safe and provided symptomatic relief from dry mouth. Practice Implications. Patients with dry mouth may benefit from this novel delivery system.

To better understand the relationship between epitope variation and tumor escape from immune surveillance, SV40 T antigen-transformed B6/K-0 cells were subjected to selection with individual CTL clones specific for the SV40 T antigen H-2D(b)-restricted epitopes I or V. CTL-resistant populations were isolated from a majority of the selection cultures and substituted epitope sequences were identified within most of the resistant populations. Tag sequences deleted of all or portions of the selection-targeted epitope were identified, but in lower numbers compared to epitope sequences bearing single residue substitutions. Relatively few flanking residue substitutions were identified, and only in epitope I-targeted selections. The diversity (numbers and epitope residue locations) of substituted epitope residue positions varied between selections. These findings suggest that the scope of spontaneously occurring mutations that could allow for escape from individual CD8+ T cell clones is large.

This case study of an active 22 year old female who sustained a traumatic incident to the right knee focuses on the differential diagnostic process. Although early subjective complaints, clinical presentation, and diagnostic testing results were commensurate with internal derangement of the knee, appropriate medical and surgical management failed to halt the progression of pain and subsequent onset of neurological symptoms. Electrodiagnostic testing conducted 10 months post initial injury produced a definitive diagnosis of an irritative lesion of the right peroneal nerve in the region of the fibular neck. A fibular tunnel release and peroneal nerve decompression was subsequently performed after which complete symptom resolution was achieved, allowing return to full functional activities.

Differences have been reported between in vitro and in vivo meniscal kinematics, and no clinical study to date has investigated the effect of meniscal repair on meniscal kinematics. Eleven subjects with healthy knees and eight subjects who had undergone meniscal repair for an isolated tear were scanned using magnetic resonance imaging. Sagittal plane scanning was performed at 0, 30, 60, 90, and 120 degrees of knee flexion. The mean composite lateral meniscus movements for the normal and meniscal-repaired subjects were 6.85 mm and 6.01 mm, respectively. The mean composite medial meniscus movement for the normal and meniscal repaired subjects were 8.22 mm and 5.91 mm, respectively. Anterior horn movements of the lateral and medial meniscus of normal subjects were 7.5 and 8.9 mm, respectively. The posterior horns of the lateral meniscus and medial meniscus displaced 6.2 mm and 7.6 mm, respectively. In comparing meniscal-repair subjects to the subjects with healthy knees, the lateral meniscus displaced approximately 6 mm for both groups. However, the medial meniscus moved 8.2 mm for the normal subjects and only 5.91 mm for the meniscal repair subjects. Posterior horn movement of the medial meniscus was determined to be reduced following meniscal repair.

The cytotoxic T-lymphocyte response to wild-type simian virus 40 large tumor antigen (Tag) in C57BL/6 (H2(b)) mice is directed against three H2-D(b)-restricted epitopes, I, II/III, and V, and one H2-K(b)-restricted epitope, IV. Epitopes I, II/III, and IV are immunodominant, while epitope V is immunorecessive. We investigated whether this hierarchical response was established in vivo or was due to differential expansion in vitro by using direct enumeration of CD8(+) T lymphocytes with Tag epitope/major histocompatibility complex class I tetramers and intracellular gamma interferon staining. The results demonstrate that epitope IV-specific CD8(+) T cells dominated the Tag-specific response in vivo following immunization with full-length Tag while CD8(+) T cells specific for epitopes I and II/III were detected at less than one-third of this level. The immunorecessive nature of epitope V was apparent in vivo, since epitope V-specific CD8(+) T cells were undetectable following immunization with full-length Tag. In contrast, high levels of epitope V-specific CD8(+) T lymphocytes were recruited in vivo following immunization and boosting with a Tag variant in which epitopes I, II/III, and IV had been inactivated. In addition, analysis of the T-cell receptor beta (TCRbeta) repertoire of Tag epitope-specific CD8(+) cells revealed that multiple TCRbeta variable regions were utilized for each epitope except Tag epitope II/III, which was limited to TCRbeta10 usage. These results indicate that the hierarchy of Tag epitope-specific CD8(+) T-cell responses is established in vivo.

Simian virus 40 (SV40) has been shown to be associated with a number of human tumours. Two other human papova viruses, BKV and JCV, infect humans at a relatively high frequency and are activated upon immune suppression. The T antigens of both of these viruses share considerable homologies with the transforming protein T antigen of SV40. We have used SV40 T antigen specific cytotoxic T lymphocyte (CTL) clones to discriminate among the T antigens of SV40, BKV and JCV. These CTL clones directed to four distinct CTL epitopes serve as specific probes and can differentiate subtle alterations or deletions in the CTL epitopes relative to SV40 T antigen. Using this strategy, we have been able to authenticate three SV40 viruses isolated from humans as all four distinct CTL epitopes in the T antigens encoded by these three SV40 human isolates (SVCPC, SVMEN, and SVPML-1) were found to be identical to prototype SV40. We have further identified a 198 amino acid deletion T antigen variant of SVCPC. The finding of a deletion mutant in the SVCPC virus population suggests that the cellular immune response may play a role in the selection of antigenic loss variants.

The quantitative polymerase chain reaction (PCR) method devised by Fujimura and Bockstahler (1995) was modified for rapid determination of distribution of HIV-1 proviral DNA load in AIDS brains. It was used for analysis of an association with HIV-1 associated dementia and HIV-1 encephalitis (Fujimura et al., 1997). The method has wider applicability for comparative studies of viral DNA load based on PCR amplification. The method is applicable under conditions where target DNA and its PCR-amplified product increase proportionally. An equation was derived to obtain the number of copies of HIV-1 DNA per cellular genome from the amount of PCR amplified product of a tissue specimen DNA. The equalizing constant is the reciprocal of the slope of the amplification of the HIV-1 proviral DNA sequence of the standard cellular DNA included in each experiment. The intercept of the equation is zero.

CD8+ cytotoxic T-lymphocytes recognize small epitope peptides in association with MHC class I molecules expressed on the cell surface. In this study, we have determined whether an 8 amino acid viral CTL epitope, when expressed in a cellular protein, can be appropriately processed, presented, and recognized by the corresponding epitope-specific CTL and whether it is capable of inducing a CTL response in vivo. An H-2Kb-restricted CTL epitope from herpes simplex virus type 1 (HSV-1) glycoprotein B (gB epitope, residues 498-505) was cloned into the mouse dihydrofolate reductase protein (DHFR) at amino acid position 87. The recombinant DHFRs were expressed in vaccinia virus recombinants. To distinguish the recombinant DHFR proteins from the endogenous DHFR, an antibody epitope, recognized by monoclonal antibody PAb 901 and derived from simian virus 40 (SV40) T antigen was tagged to the C-termini of recombinant DHFR proteins. In vivo expression of recombinant DHFR was demonstrated by immunoprecipitation with the monoclonal antibody PAb 901. The H-2b cells infected with recombinant vaccinia virus expressing the recombinant DHFR were specifically lysed by gB epitope-specific CTL. Furthermore, the recombinant DHFR was functional in inducing a long lasting HSV gB epitope-specific CTL response upon immunization of C57BL/6 (B6) mice. These results indicate that a viral epitope expressed in a cellular protein can be efficiently processed, presented, and recognized by epitope-specific CTL and show that cellular proteins expressing CTL epitopes can be used for induction of CD8+ T lymphocyte responses.

The simian virus 40 large T antigen immortalizes growing primary cells in culture. In addition, this viral oncoprotein cooperates with an activated ras protein to produce dense foci on monolayers of rat embryo fibroblasts (REF). The relationship between independent immortalization and cooperative transformation with ras has not been defined. Previously, two regions of T antigen were shown to contain immortalization activities. An N-terminal fragment consisting of amino acids 1 to 147 immortalizes rodent cells (L. Sompayrac and K. J. Danna, Virology 181:412-415, 1991). Loss-of-function analysis indicated that immortalization depended on integrity of the T-antigen segments containing amino acids 351 to 450 and 533 to 626 (T. D. Kierstead and M. J. Tevethia, J. Virol. 67:1817-1829, 1993). The experiments described here were directed toward determining whether these same T-antigen regions were sufficient for cooperation with ras. Initially, constructs that produce T antigens containing amino acids 176 to 708 (T176-708) or 1 to 147 were tested in a ras cooperation assay. Both polypeptides cooperated with ras to produce dense foci on monolayers of primary REF. These results showed that T antigen contains two separate ras cooperation activities. In order to determine the N-terminal limit of the ras cooperation activity contained within the T176-708 polypeptide, a series of constructs designed to produce fusion proteins containing T-antigen segments beginning at residues 251, 301, 337, 351, 371, 401, 451, 501, 551, 601, and 651 was generated. Each of these constructs was tested for the capacity to cooperate with ras to produce dense foci on REF monolayers. The results indicated that a polypeptide containing T-antigen amino acids 251 to 708 (T251-708) was sufficient to cooperate with ras, whereas the more extensively truncated products were not. The abilities of the N-terminally truncated T antigens to bind p53 were examined in p53-deficient cells infected with a recombinant vaccinia virus expressing a phenotypically wild-type mouse p53. The results showed that polypeptides containing T-antigen amino acids 251 to 708, 301 to 708, 337 to 708, or 351 to 708 retained p53-binding capacity. The introduction into the T251-708 polypeptide of deletions that either prevented p53 binding (dl434-444) or did not prevent p53 binding (dl400) abrogated ras cooperation. These results indicated that although p53 binding may be necessary for ras cooperation, an additional, as-yet-undefined activity contained within the T251-708 polypeptide is needed.

Human papovavirus JC (JCV) and simian virus 40 (SV40) genomes share approximately 69% homology; and there is antigenic cross-reactivity between JCV and SV40 tumor or T antigens. In order to determine whether a selective immune response to JCV T antigen could be demonstrated, transgenic mice (SV11+) that express SV40 T antigen in the choroid plexus and are partially tolerant to antigenic determinants on SV40 T antigen were immunized with SV40 or JCV T antigens and their antibody responses were analyzed. The results show that SV11+ mice responded as well as their nontransgenic litter mates to JCV T antigen. Monoclonal antibodies were derived from hybridomas generated from immunized mice which reacted specifically with epitopes in the amino and carboxy terminal halves on JCV T antigen. These studies show that transgenic mice expressing SV40 T antigen are capable of responding to determinants not shared between JCV and SV40 T antigen.

The results are presented which confirm applicability of the Valsalva test as a functional exercise for the cardiovascular system while studying changes of the circulation regulation under high ambient pressure. Methods of transthoracic tetrapolar impedance plethysmography, electro- and intervalocardiography and mean arterial pressure measurement by means of the oscillometric servosystem are shown as adequate and highly informative under these conditions.

Subtalar ankle inversion with and without AirStirrup application was evaluated using high speed cinematographic techniques and a specially designed platform that inverts the ankle 35 O. Eighteen subjects aged 19 to 35 and with no history of ankle injury participated in the study. Two trials were filmed for each subject. Although the same ankle was tested in each trial, AirStirrups were applied to both ankles in one trial and to neither in the other trial so subjects could not anticipate the inversion stress. Points marked on the knee (posterior), the Achilles tendon, and the distal calcaneous were digitized. These data were smoothed employing cubic splines and used to calculate the maximum angular displacement (inversion) at the subtalar joint in each of the conditions tested. A t-test revealed a significantly (p c 0.001) larger inversion angle for the ankle not braced with fhe AirStirrup. J Orthop Sports Phys Ther 1987;9(5):190-193.

Classic tennis elbow, or lateral epicondylitis, has been described as an overuse or misuse injury resulting in a tendinitis. The extensor carpi radialis brevis (ECRB) and extensor digitorum communis (EDC) have been implicated as primary culprits in this pathology. Tennis elbow has been treated using a constrictive band placed several centimeters distal to the origin of these two muscles. Aircast (Aircast Inc., Summit, NJ) has developed a new style of band that employs an air-filled bladder as the counterpressure element. This study tested the effect of both standard and Aircast bands on EMG activity of the EDC and ECRB proximal to the band compared to control values. Ten normal subjects, ranging in age from 20 to 43 years, were tested. Right upper extremities were tested in all cases. The subjects' forearms were stabilized in the CYBEX II forearm stabilization V-pad. The ECRB and EDC were then impaled with monopolar EMG needle electrodes. The CYBEX data were recorded using the HUMAC system and the EMG data were recorded and analyzed using the Cadwell 7400. EMG data were recorded at 80% of maximum voluntary isometric contraction (MVIC) with no band, the standard band, and the Aircast band. An analysis of variance (ANOVA) with repeated measures of integrated EMG (IEMG) and Duncan's multiple comparison tests revealed that the Aircast caused a significant reduction in IEMG of the ECRB and EDC when compared with control values and the standard band. The decrease in IEMG with the standard band was not statistically significant.(ABSTRACT TRUNCATED AT 250 WORDS)

The purposes of this paper are to describe an objective technique developed to assess the dynamic response of the peroneal muscles to a sudden inversion motion and to report the results obtained from testing injured and noninjured ankles. A platform was constructed to drop the ankle into a controlled degree of inversion while measuring the time to peroneal response and the angular rotation. Thirty volunteers were tested, 15 of whom had experienced a unilateral ankle sprain 3- 10 months prior to testing. Results show a trend toward delayed peroneal response and greater angular displacement at the time of peroneal response in injured ankles but analysis of variance showed no significant difference. The total angular displacement in the injured ankles was significantly greater. This objective technique could be used to evaluate treatment regimens and, by testing ankles soon after injury and serially, to evaluate readiness to return to activity. J Orthop Sports Phys Ther 1985;7(3):107-109.