bluuebunny/crossref_metadata_2025 huggingface dataset:
Frequency Modulation of Motor Unit Discharge Has Task-Dependent Effects on Fluctuations in Motor Output
Authors: Mottram Carol J. , Christou Evangelos A. , Meyer François G. , Enoka Roger M.
Published: July 2005

The rate of change in the fluctuations in motor output differs during the performance of fatiguing contractions that involve different types of loads. The purpose of this study was to examine the contribution of frequency modulation of motor unit discharge to the fluctuations in the motor output during sustained contractions with the force and position tasks. In separate tests with the upper arm vertical and the elbow flexed to 1.57 rad, the seated subjects maintained either a constant upward force at the wrist (force task) or a constant elbow angle (position task). The force and position tasks were performed in random order at a target force equal to 3.6 ± 2.1% (mean ± SD) of the maximal voluntary contraction (MVC) force above the recruitment threshold of an isolated motor unit from the biceps brachii. Each subject maintained the two tasks for an identical duration (161 ± 93 s) at a mean target force of 22.4 ± 13.6% MVC. As expected, the rate of increase in the fluctuations in motor output (force task: SD for detrended force; position task: SD for vertical acceleration) was greater for the position task than the force task ( P < 0.001). The amplitude of the coefficient of variation (CV) and the power spectra for motor unit discharge were similar between tasks ( P > 0.1) and did not change with time ( P > 0.1), and could not explain the different rates of increase in motor output fluctuations for the two tasks. Nonetheless, frequency modulation of motor unit discharge differed during the two tasks and predicted ( P < 0.001) both the CV for discharge rate (force task: 1–3, 12–13, and 14–15 Hz; position task: 0–1, and 1–2 Hz) and the fluctuations in motor output (force task: 5–6, 9–10, 12–13, and 14–15 Hz; position task: 6–7, 14–15, 17–19, 20–21, and 23–24 Hz). Frequency modulation of motor unit discharge rate differed for the force and position tasks and influenced the ability to sustain steady contractions.
Increases in Corticospinal Tract Function by Treadmill Training After Incomplete Spinal Cord Injury
Authors: Thomas Sarah L. , Gorassini Monica A.
Published: July 2005

In this study, we examined if several months of intensive locomotor training increases the function of spared corticospinal tract pathways after chronic spinal cord injury (SCI) in association with the recovery of locomotor function. Transcranial magnetic stimulation (TMS) at incrementing levels of intensity was applied over the motor cortex supplying either the tibialis anterior or vastus lateralis muscles, and the resulting peak-to-peak amplitude of the motor-evoked potentials (MEPs) were measured to obtain a recruitment curve both before and after training. In the majority of subjects (7/8), 3–5 mo of daily intensive training increased the responses to TMS in at least one of the leg muscles tested (9/13). On average, across all muscles tested MEPmax, which was evoked at high stimulation intensities, increased by 46% and MEPh, which was evoked at intermediate stimulation intensities, increased by 45% (both significantly different from 0), indicating an increase in corticospinal tract connectivity from training. The slope of the sigmoid function fit to the recruitment curve increased by 24% after training (significantly different), indicating an expansion and/or increased excitability of corticospinal circuits supplying muscles to the lower leg. We also observed that the average duration of the silent period measured at MEPmax increased after training from 130 to 178 ms, suggesting that training had effects on cortical circuits thought to mediate this long-lasting inhibition. The percentage increase in MEPmax was positively and significantly correlated to the degree of locomotor recovery as assessed by the WISCI II score, the distance a subject could walk in 6 min, and the amplitude of the locomotor EMG activity, suggesting that the corticospinal tract, in part, mediated the functional locomotor recovery produced from training.
Corticofugal Feedback for Collicular Plasticity Evoked by Electric Stimulation of the Inferior Colliculus
Authors: Zhang Yongkui , Suga Nobuo
Published: July 2005

Focal electric stimulation of the auditory cortex, 30-min repetitive acoustic stimulation, and auditory fear conditioning each evoke shifts of the frequency-tuning curves [hereafter, best frequency (BF) shifts] of cortical and collicular neurons. The short-term collicular BF shift is produced by the corticofugal system and primarily depends on the relationship in BF between a recorded collicular and a stimulated cortical neuron or between the BF of a recorded collicular neuron and the frequency of an acoustic stimulus. However, it has been unknown whether focal electric stimulation of the inferior colliculus evokes the collicular BF shift and whether the collicular BF shift, if evoked, depends on corticofugal feedback. In our present research with the awake big brown bat, we found that focal electric stimulation of collicular neurons evoked the BF shifts of collicular neurons located near the stimulated ones; that there were two types of BF shifts: centripetal and centrifugal BF shifts, i.e., shifts toward and shifts away from the BF of stimulated neurons, respectively; and that the development of these collicular BF shifts was blocked by inactivation of the auditory cortex. Our data indicate that the collicular BF shifts (plasticity) evoked by collicular electric stimulation depended on corticofugal feedback. It should be noted that collicular BF shifts also depend on acetylcholine because it has been demonstrated that atropine (an antagonist of muscarinic acetylcholine receptors) applied to the IC blocks the development of collicular BF shifts.
Unraveling Interlimb Interactions Underlying Bimanual Coordination
Authors: Ridderikhoff Arne , Peper C. (Lieke) E. , Beek Peter J.
Published: July 2005

Three sources of interlimb interactions have been postulated to underlie the stability characteristics of bimanual coordination but have never been evaluated in conjunction: integrated timing of feedforward control signals, phase entrainment by contralateral afference, and timing corrections based on the perceived error of relative phase. In this study, the relative contributions of these interactions were discerned through systematic comparisons of five tasks involving rhythmic flexion–extension movements about the wrist, performed bimanually (in-phase and antiphase coordination) or unimanually with or without comparable passive movements of the contralateral hand. The main findings were the following. 1) Contralateral passive movements during unimanual active movements induced phase entrainment to interlimb phasing of either 0° (in-phase) or 180° (antiphase). 2) Entrainment strength increased with the passive movements' amplitude, but was similar for in-phase and antiphase movements. 3) Coordination of unimanual active movements with passive movements of the contralateral hand (kinesthetic tracking) was characterized by similar bilateral EMG activity as observed in active bimanual coordination. 4) During kinesthetic tracking the timing of the movements of the active hand was modulated by afference-based error corrections, which were more pronounced during in-phase coordination. 5) Indications of in-phase coordination being more stable than antiphase coordination were most prominent during active bimanual coordination and marginal during kinesthetic tracking. Together the results indicated that phase entrainment by contralateral afference contributed equally to the stability of in-phase and antiphase coordination, and that differential stability of these patterns depended predominantly on integrated timing of feedforward signals, with only a minor role for afference-based error corrections.
Paul, Polemics, and the Problem of Essentialism
Authors: Eisenbaum Pamela
Published: July 2005

The study of Paul—more than the study of Jesus—has been and continues to be the arena of discourse where Christians (and recently some Jews) work out their religious identity. Put another way, reading, interpreting and reinterpreting Paul fosters the construction, reconstruction, and sometimes deconstruction of the boundary that marks the distinction between Christianity and Judaism.Since there exists much scholarship on how the history of the interpretation of Paul has been motivated by Christian–Jewish polemic, I will not illustrate that history here. Instead, I wish to highlight two things that distinguish the contemporary debate from previous ones: 1) There is input from the Jewish side—both in terms of content and persons,—which has led to what many think of as a "Jewish" understanding of Paul; and 2) that this Jewish perspective on Paul is not only perceived by some scholars as problematic, wrong, or misguided but as a threat to Christianity itself, thus proving that Christian–Jewish polemic is alive and well in Pauline studies, in spite of recent widespread acknowledgment of Paul's Jewishness!Demonstrating that these two qualities characterize current debate about Paul is not difficult to do. However, by discussing these two aspects of Pauline scholarship, I intend to complicate the notion of religious identity at work in the interpretation of Paul, in an effort to reveal that an essentialist understanding of religious identity underlies the debate about Paul's Jewishness. This kind of essentialism fails to account for the elasticity within religious traditions and the permeability between religious traditions, and thus it greatly exacerbates the problem of Christian–Jewish polemic in the study of Paul. Unless we grasp the flexibility that inheres in religious identity, which includes giving up the notion of essentialism, the study of Paul will continue to be marred by these polemics.
An American "myth of Innocence" and Contemporary Pauline Studies
Authors: Elliott Neil
Published: July 2005

Richard Hughes discusses the "Myths America Lives By," including myths of national innocence and national destiny. Hughes' discussion is particularly relevant to the American context of Pauline studies after the Shoah, where "American" values of inclusiveness and "universalism" are opposed to ethnic intolerance. Ironically, in some versions of the so-called "new perspective on Paul," the latter is usually identified with the "Jewish exclusivism" that Paul opposed.Increasing criticisms have been raised against this construal of Paul's theology. Efforts to rehabilitate Paul by opposing him to Jewish ethnocentrism rely on caricature and stigmatize fundamental Jewish identity and observance. In contrast, an explicitly political reading, attending to aspects of counter-imperial dissent in Paul's letters, however uncongenial to the mythology of American innocence and destiny, may provide deeper insight into the contours of Paul's interaction with alternative Jewish discourses under Roman rule.
Football Equipment Design Affects Face Mask Removal Efficiency
Authors: Swartz Erik E. , Norkus Susan A. , Cappaert Tom , Decoster Laura C.
Published: July 2005

Background

Researchers have investigated the performance of face mask removal tools for spine injury management in football but not the effects of football equipment design.

Hypotheses

Various styles or designs of football helmet equipment (helmets, face masks, loop straps) affect face mask removal efficiency. A cordless screwdriver performs more efficiently than do cutting tools.

Study Design

Controlled laboratory study.

Methods

Nineteen certified athletic trainers were randomly assigned to group 1 (cordless screwdriver and the FM Extractor) or group 2 (cordless screwdriver and the Trainer's Angel). Subjects randomly performed face mask removal for 6 conditions composed of helmet (3), face mask (3), and loop strap (5) combinations. Time, head movement, perceived difficulty, and success rates were measured.

Results

Multiple significant differences were found in time, movement, and perceived difficulty between the 6 helmet equipment conditions. The Shockblocker loop strap was consistently superior in all variables regardless of the tool used or the helmet it was attached to. The cordless screwdriver created less movement (mean range from any one plane, 2.8°-13.3°), was faster (mean range, 42.1-68.8 seconds), and was less difficult (mean rating of perceived exertion range, 1.4-2.9) compared to cutting tools (ranges, 4.4°-18.4° in any one plane, 71-174 seconds, rating of perceived exertion, 2.8-7.7). Trial failure was more common with cutting tools than with the screwdriver.

Conclusion

Differences in football helmet equipment affect face mask removal. The cordless screwdriver is more efficient than the FM Extractor and Trainer's Angel.

Clinical Relevance

Professionals responsible for the care of football athletes must be knowledgeable in the types of equipment used and the best option available for effective airway access.
The “Ligamentization” Process in Human Anterior Cruciate Ligament Reconstruction with Autogenous Patellar and Hamstring Tendons
Authors: Marumo Keishi , Saito Mitsuru , Yamagishi Tsuneo , Fujii Katsuyuki
Published: July 2005

Background

There is little information documenting whether the phenomenon of “ligamentization,” as proposed by Amiel, occurs in the human anterior cruciate ligament after clinically effective reconstruction. To clarify this point, we analyzed biochemical differences between the native anterior cruciate ligament; the patellar, semitendinosus, and gracilis tendons; and anterior cruciate ligaments reconstructed with autografts.

Study Design

Cohort study; Level of evidence, 2.

Methods

Fifty patients who underwent arthroscopically assisted anterior cruciate ligament reconstruction using either semi-tendinosus and gracilis tendon or bone-patellar tendon-bone autografts were selected for the study. Samples of grafted tissue were collected during arthroscopy and quantitatively analyzed for collagen content and the amount of reducible and nonreducible crosslinks at 4 to 6 postoperative months in patients with semitendinosus and gracilis tendon grafts and at 11 to 13 months in all patients with semitendinosus and gracilis tendon or bone-patellar tendon-bone grafts.

Results

The total collagen content and nonreducible/reducible crosslink ratios increased significantly during the postoperative period (P < .05). The dihydroxylysinonorleucine/hydroxylysinonorleucine ratio was 3.11 ± 0.56 in the native anterior cruciate ligament, 1.21 ± 0.47 in the patellar tendon, and 3.59 ± 1.58 in the anterior cruciate ligaments reconstructed with bone-patellar tendon-bone autografts 1 year after surgery. The dihydroxylysinonorleucine/hydroxylysinonorleucine ratio in both semitendinosus and gracilis tendons was less than 1.0. However, in anterior cruciate ligaments reconstructed with semitendinosus and gracilis tendon autografts, it was 2.34 ± 0.98 at 4 to 6 months and 3.43 ± 1.61 at 11 to 13 months after the operation.

Conclusions

After anterior cruciate ligament reconstruction with autografts, biochemical characteristics of the graft resembled those of the native anterior cruciate ligament. These findings suggest that, regarding the amount of collagen crosslinks and their architecture, the phenomenon of ligamentization occurs in the successfully reconstructed human anterior cruciate ligament within 1 year after operation.
Long-Term Evaluation of the Roux-Elmslie-Trillat Procedure for Patellar Instability
Authors: Carney Joseph R. , Mologne Timothy S. , Muldoon Michael , Cox Jay S.
Published: July 2005

Background

Few published articles exist reporting the long-term evaluation of the Roux-Elmslie-Trillat procedure.

Purpose

To assess the long-term effect of the Roux-Elmslie-Trillat procedure in preventing recurrent subluxation and dislocation of the patella.

Study Design

Case series; Level of evidence, 4.

Methods

Eighteen patients who underwent the Roux-Elmslie-Trillat procedure for dislocation or subluxation of the patella were identified from a group previously evaluated at a mean follow-up of 3 years. The prevalence of recurrent subluxation or dislocation at a mean follow-up of 26 years was compared with the prevalence reported at the mean follow-up of 3 years. Although not the focus of this study, Cox functional scores were obtained from the smaller group and compared with the results at the 3-year follow-up.

Results

Seven percent (95% confidence interval, 0.00-0.32) of the patients had recurrent subluxation at 26 years compared with 7% (95% confidence interval, 0.03-0.13) of the study population reported at 3 years (P = 1.00). Fifty-four percent (95% confidence interval, 0.27-0.79) rated their affected knee as good or excellent at 26 years compared with 73% (95% confidence interval, 0.64-0.81) of the larger study population reported at 3 years (P = .14).

Conclusion

The prevalence of recurrent subluxation and dislocation in patients with patellofemoral malalignment who underwent the Roux-Elmslie-Trillat procedure for dislocation or subluxation of the patella is similar at 3 and 26 years after the procedure. The long-term functional status of the affected knee in patients who underwent the Roux-Elmslie-Trillat procedure declined.
Application of Tissue Engineering Techniques for Rotator Cuff Regeneration Using a Chitosan-Based Hyaluronan Hybrid Fiber Scaffold
Authors: Funakoshi Tadanao , Majima Tokifumi , Iwasaki Norimasa , Suenaga Naoki , Sawaguchi Naohiro , Shimode Kazumi , Minami Akio , Harada Kazuo , Nishimura Shin-ichiro
Published: July 2005

Background

The current surgical procedures for irreparable rotator cuff tears have considerable limitations. Tissue engineering techniques using novel scaffold materials offer potential alternatives for managing these conditions.

Hypothesis

A chitosan-based hyaluronan hybrid scaffold could enhance type I collagen products with seeded fibroblasts and thereby increase the mechanical strength of regenerated tendon in vivo.

Study Design

Controlled laboratory study.

Methods

The scaffolds were created from chitosan-based hyaluronan hybrid polymer fibers. Forty-eight rabbit infraspinatus tendons and their humeral insertions were removed to create defects. Each defect was covered with a fibroblast-seeded scaffold (n = 16) or a non-fibroblast-seeded scaffold (n = 16). In the other 16 shoulders, the rotator cuff defect was left free as the control. At 4 and 12 weeks after surgery, the engineered tendons were assessed by histological, immunohistochemical (n = 2), and biomechanical (n = 6) analyses.

Results

Type I collagen was only seen in the fibroblast-seeded scaffold and increased in the regenerated tissue. The tensile strength and tangent modulus in the fibroblast-seeded scaffold were significantly improved from 4 to 12 weeks postoperatively. The fibroblast-seeded scaffold had a significantly greater tangent modulus than did the non-fibroblast-seeded scaffold and the control at 12 weeks.

Conclusion

This scaffold material enhanced the production of type I collagen and led to improved mechanical strength in the regenerated tissues of the rotator cuff in vivo.

Clinical Relevance

Rotator cuff regeneration is feasible using this tissue engineering technique.
Tendon-to-Bone Pressure Distributions at a Repaired Rotator Cuff Footprint Using Transosseous Suture and Suture Anchor Fixation Techniques
Authors: Park Maxwell C. , Cadet Edwin R. , Levine William N. , Bigliani Louis U. , Ahmad Christopher S.
Published: July 2005

Background

Interface contact pressure between the tendon and bone has been shown to influence healing. This study evaluates the interface pressure of the rotator cuff tendon to the greater tuberosity for different rotator cuff repair techniques.

Hypothesis

The transosseous tunnel rotator cuff repair technique provides larger pressure distributions over a defined insertion footprint than do suture anchor techniques.

Study Design

Controlled laboratory study.

Methods

Simulated rotator cuff tears over a 1 × 2-cm infraspinatus insertion footprint were created in 25 bovine shoulders. A transosseous tunnel simple suture technique (n = 8), suture anchor simple technique (n = 9), and suture anchor mattress technique (n = 8) were used for repair. Pressurized contact areas and mean pressures of the repaired tendon against the tuberosity were determined using pressure-sensitive film placed between the tendon and the tuberosity.

Results

The mean contact area between the tendon and tuberosity insertion footprint was significantly greater for the transosseous technique (67.7 ± 5.8 mm2) compared with the suture anchor simple (34.1 ± 9.4 mm2) and suture anchor mattress (26.0 ±5.3 mm2) techniques (P < .05). The mean interface pressure exerted over the footprint by the tendon was also greater for the transosseous technique (0.32 ± 0.05 MPa) compared with the suture anchor simple (0.26 ± 0.04 MPa) and suture anchor mattress (0.24 ± 0.02 MPa) techniques (P < .05).

Conclusion

The transosseous tunnel rotator cuff repair technique creates significantly more contact and greater overall pressure distribution over a defined footprint when compared with suture anchor techniques.

Clinical Relevance

Stronger and faster rotator cuff healing may be expected when beneficial pressure distributions exist between the repaired rotator cuff and its insertion footprint. Tendon-to-tuberosity pressure and contact characteristics should be considered in the development of improved open and arthroscopic rotator cuff repair techniques.
Popliteomeniscal Fascicle Tears Causing Symptomatic Lateral Compartment Knee Pain
Authors: LaPrade Robert F. , Konowalchuk Brian K.
Published: July 2005

Background

Injuries to the popliteomeniscal fascicles of the lateral meniscus are difficult to identify from physical examination and magnetic resonance imaging scans. To our knowledge, there have been no described physical examination techniques to identify symptomatic isolated popliteomeniscal fascicle tears. The popliteomeniscal fascicles have been demonstrated to be important for lateral meniscus stability, and it has been reported that tears can lead to painful symptoms.

Hypothesis

Popliteomeniscal fascicle tears cause symptomatic lateral compartment knee pain and can be diagnosed by physical examination. Surgical repair can improve patient function.

Study Design

Case series; Level of evidence, 4.

Methods

Six patients with isolated tears of the popliteomeniscal fascicles, which caused lateral joint line knee pain, were identified by positive figure-4 test results.

Results

All patients were found to have replication of their symptoms while placing the affected knee in the figure-4 position and were found to have lateral meniscal hypermobility due to tears of the popliteomeniscal fascicles on arthroscopic examination. All patients had an open repair of the popliteomeniscal fascicles of the lateral meniscus with complete resolution of their symptoms at a mean follow-up of 3.8 years postoperatively.

Conclusions

The figure-4 test was found to be useful in identifying the source of lateral compartment knee pain due to popliteomeniscal fascicle tears. Open repair of isolated popliteomeniscal fascicle tears was also found to be effective in resolving lateral compartment knee pain due to popliteomeniscal fascicle tears.
Functional Outcome of Knee Articular Cartilage Repair in Adolescent Athletes
Authors: Mithöfer Kai , Minas Tom , Peterson Lars , Yeon Howard , Micheli Lyle J.
Published: July 2005

Background

Limited information exists about the treatment of full-thickness articular cartilage lesions of the knee in adolescent athletes.

Purpose

To evaluate the functional outcome and athletic activity after articular cartilage repair in the knees of adolescent athletes.

Study Design

Case series; Level of evidence, 4.

Methods

Twenty adolescent athletes with full-thickness articular cartilage lesions of the knee were treated with autologous chondrocyte transplantation. Functional outcome was evaluated by subjective patient outcome rating, knee activity scores, and level of athletic participation.

Results

At a mean of 47 months after autologous chondrocyte transplantation, 96% of adolescents reported good or excellent results with significant increases in postoperative Tegner activity scores and Lysholm scores. Ninety-six percent returned to high-impact sports and 60% to an athletic level equal or higher than that before knee injury. Return to preinjury sports correlated with shorter preoperative symptoms and a lower number of prior operations. All adolescents with preoperative symptoms ≤12 months returned to preinjury-level athletics, compared to 33% with preoperative intervals longer than 12 months.

Conclusion

Treatment of full-thickness articular injuries of the knee in adolescent athletes with autologous chondrocyte transplantation yields a high rate of functional success at a mean follow-up of 47 months. The rate of return to demanding athletic activities is higher in cases in which the preoperative duration of symptoms is 12 months or less.
The Effect of Long-Distance Bicycling on Ulnar and Median Nerves
Authors: Akuthota Venu , Plastaras Christopher , Lindberg Kirstin , Tobey John , Press Joel , Garvan Cynthia
Published: July 2005

Background

Distal ulnar neuropathies have been identified in cyclists because of prolonged grip pressures on handlebars. The so-called cyclist palsy has been postulated to be an entrapment neuropathy of the ulnar nerve in the Guyon canal of the wrist. Previous studies utilizing nerve conduction studies have typically been either case reports or small case series.

Hypothesis

Electrophysiologic changes will be present in the ulnar and median nerves after a long-distance multiday cycling event.

Study Design

Cohort study; Level of evidence, 2.

Methods

A total of 28 adult hands from 14 subjects underwent median and ulnar motor and sensory nerve conductions, which were performed on both hands before and after a 6-day, 420-mile bike tour. A ride questionnaire was also administered after the ride, evaluating the experience level of the cyclist, equipment issues, hand position, and symptoms during the ride.

Results

Distal motor latencies of the deep branch of the ulnar nerve to the first dorsal interosseous were significantly prolonged after the long-distance cycling event. The median motor and sensory studies as well as the ulnar sensory and motor studies of the abductor digiti minimi did not change significantly. Electrophysiologic and symptomatic worsening of carpal tunnel syndrome was observed in 3 hands, with the onset of carpal tunnel syndrome in 1 hand after the ride.

Conclusion

Long-distance cycling may promote physiologic changes in the deep branch of the ulnar nerve and exacerbate symptoms of carpal tunnel syndrome.
Deteriorating Outcomes after Meniscal Repair Using the Meniscus Arrow in Knees Undergoing Concurrent Anterior Cruciate Ligament Reconstruction
Authors: Lee Gregory P. , Diduch David R.
Published: July 2005

Background

An increased awareness of the degenerative changes that occur in the knee after meniscectomy has led to efforts to salvage the injured meniscus. Numerous devices have been developed in an effort to provide the dual benefits of a durable meniscal repair and minimal invasiveness.

Hypothesis

The Meniscus Arrow is comparable to conventional inside-out suture repair in accomplishing long-term healing of meniscal tears.

Study Design

Case series; Level of evidence, 4.

Methods

This study is an extended follow-up of an original series of 32 patients withoutcomes analysis. All patients underwent meniscal repair with exclusive use of the arrow. All repairs were performed in the context of a concomitant anterior cruciate ligament reconstruction. Follow-up assessment included physical examination, arthrometry, the International Knee Documentation Committee instrument, and the Knee Disorders Subjective History visual analog scale. Intermediate follow-up at a mean of 2.3 years yielded a success rate of 90.6%. The mean follow-up in the present study has been extended to 6.6 years.

Results

The extended follow-up analysis revealed a substantial attrition in the success rate of this series of patients undergoing meniscal repair with the arrow. A 90.6% success rate at a mean follow-up of 2.3 years deteriorated to 71.4% at 6.6 years.

Conclusion

This study provides the longest follow-up in the literature of any of the all-inside meniscal repair implants. The Meniscus Arrow demonstrated long-term meniscal healing rates inferior to those found in the literature for inside-out suture repair techniques.
Being Young, Brown, and Hindu
Authors: Kurien Prema A.
Published: July 2005

The “new second generation,” the children of post-1965 immigrants, is the focus of scholars who recognize that it is the critical generation who will determine the future patterns of race and ethnicity in the United States. Based on a case study of a Hindu Student Council chapter at “Western University” in California, this article looks at how the attempts by second-generation Indian Americans to deal with issues of race brought many of them to the organization but also produced conflicts and cleavages within it. The purpose of my analysis is to argue that religious institutions often play a crucial role in the identity construction of new Americans and that the complex interplay between race, ethnicity, and religion has been ignored by the dominant sociological models of immigrant incorporation. I also show how and why conventional American categories of race and ethnicity are often inadequate for understanding the experiences of contemporary immigrants and their children.
The Benefits of Being There
Authors: Tope Daniel , Chamberlain Lindsey Joyce , Crowley Martha , Hodson Randy
Published: July 2005

This study draws on the sociology of work to extend discussions of informational yield in ethnographic research. The authors examine the existing population of English-language workplace ethnographies and find that relative to interviews, observation and especially participant observation consistently yield more information. Participant observation provides greater informational yield as well as more detailed descriptions of workplace behaviors and group dynamics. Interviews, however, are more likely to provide information on basic organizational characteristics, such as organization size and product market conditions. The authors’ findings have important implications for university institutional review boards, which have in recent years made it increasingly difficult for projects based on participant observation to receive human subjects clearance. Our conclusions caution against bureaucratic and legalistic curtailments of embedded field observation.
Families’ Experiences of Support Provided by Resource-Oriented Family Professionals in Finland
Authors: Häggman-Laitila Arja
Published: July 2005

This study describes the support provided by resource-oriented family workers in Finland and the prerequisites for such support. Family workers consisted of professionals such as public health nurses, nurses, social educators, psychologists, kindergarten teachers, and social workers. The overall research project consisted of four separate studies carried out within the Families With Children Project. The findings of the four studies were aggregated and submitted to a secondary analysis. Interview data from 51 parents across 44 families with young children were included in the analysis. The families reported that they received emotional, cognitive, instrumental, and community and network support from the family workers. The work of resource-oriented family professionals was facilitated by the arrangements and orientation of the service model and by the quality of interaction between the family worker and the family. The families’ experiences of support underlined the multiple dimensions of the cooperative relationship and the usefulness of the supportive interaction. The findings extend the understanding of resource-oriented family work from the perspective of families and offer important implications for the caring of families with young children.
The Influence of Family on Immigrant South Asian Women’s Health
Authors: Grewal Sukhdev , Bottorff Joan L. , Hilton B. Ann
Published: July 2005

The purpose of this study was to examine the influence of family members on immigrant South Asian women’s health and health-seeking behavior. This qualitative study was part of a larger study that examined the health-seeking practices of immigrant South Asian women living in the Lower Mainland of British Columbia, Canada. Using ethnographic methods, data were collected through face-to-face interviews with women who had lived in Canada for 10 months to 31 years. Analysis of translated and transcribed data revealed that women made decisions about their health in consultation with family members. Overall, family members were perceived to be supportive and provided direct and indirect assistance to women in ways that influenced their health. Expected roles and responsibilities often had detrimental influences on women’s health. Health care for immigrant South Asian women needs to take into account women’s relationships with family members and the influence of family on women’s health.
Service Needs of Families With Children With ADHD
Authors: Kendall Judy , Leo Michael C. , Perrin Nancy , Hatton Diane
Published: July 2005

This article describes service use, perceived helpfulness of services, and the services requested of 157 families living with a child or adolescent with attention-deficit/hyperactivity disorder (ADHD) and specifically asks if service use and service need is a function of certain social demographic factors. Whereas these data suggest that ADHD is a fairly universal experience, as indicated by the high rate of service use across ethnic groups, income status, sex, and family composition, single-mother families used the most services, Hispanic families used the fewest, and families with boys with ADHD used more services than families with girls with ADHD. Income was not a significant factor in any services used or services requested. This study lends strength to the argument that more specialized services for certain groups are needed in venues with local community services, such as schools, where the majority of these children and families are already seeking help.
IL-4 increases type 2, but not type 1, cytokine production in CD8+ T cells from mild atopic asthmatics
Authors: Stanciu Luminita A , Roberts Kevan , Papadopoulos Nikolaos G , Cho Sang-Heon , Holgate Stephen T , Coyle Anthony J , Johnston Sebastian L
Published: July 2005

Background

Virus infections are the major cause of asthma exacerbations. CD8+T cells have an important role in antiviral immune responses and animal studies suggest a role for CD8+T cells in the pathogenesis of virus-induced asthma exacerbations. We have previously shown that the presence of IL-4 during stimulation increases the frequency of IL-5-positive cells and CD30 surface staining in CD8+T cells from healthy, normal subjects. In this study, we investigated whether excess IL-4 during repeated TCR/CD3 stimulation of CD8+T cells from atopic asthmatic subjects alters the balance of type 1/type 2 cytokine production in favour of the latter.

Methods

Peripheral blood CD8+T cells from mild atopic asthmatic subjects were stimulatedin vitrowith anti-CD3 and IL-2 ± excess IL-4 and the expression of activation and adhesion molecules and type 1 and type 2 cytokine production were assessed.

Results

Surface expression of very late antigen-4 [VLA-4] and LFA-1 was decreased and the production of the type 2 cytokines IL-5 and IL-13 was augmented by the presence of IL-4 during stimulation of CD8+T cells from mild atopic asthmatics.

Conclusion

These data suggest that during a respiratory virus infection activated CD8+T cells from asthmatic subjects may produce excess type 2 cytokines and may contribute to asthma exacerbation by augmenting allergic inflammation.
Elevated ex vivo monocyte chemotactic protein-1 (CCL2) in pulmonary as compared with extra-pulmonary tuberculosis
Authors: Hasan Zahra , Zaidi Irfan , Jamil Bushra , Khan M Aslam , Kanji Akbar , Hussain Rabia
Published: July 2005

Background

Tuberculosis causes 3 million deaths annually. The most common site of tuberculosis is pulmonary however; extra-pulmonary forms of the disease also remain prevalent. Restriction ofMycobacterium tuberculosisdepends on effective recruitment and subsequent activation of T lymphocytes, mononuclear and polymorphonuclear cells to the site of infection. Tumor necrosis factor (TNF)-α is essential for granuloma formation and is a potent activator of monocyte chemotactic protein (MCP-1, CCL2). CCL2 is essential for recruitment of monocytes and T cells and has been shown to play a role in protection against tuberculosis. Interleukin -8 (CXCL8) is a potent activator of neutrophils. Increased levels of CCL2, CXCL8 and TNFα are reported in tuberculosis but their significance in different forms of tuberculosis is as yet unclear. We have used anex vivoassay to investigate differences in immune parameters in patients with either pulmonary or extra-pulmonary tuberculosis.

Methods

Serum levels of CCL2, CXCL8 and TNFα were measured in patients with pulmonary tuberculosis (N = 12), extra-pulmonary tuberculosis (N = 8) and BCG-vaccinated healthy volunteers (N = 12). Whole blood cells were stimulated with non-pathogenicMycobacterium bovisbacille-Calmette Guerin (BCG) vaccine strain or bacterial lipopolysaccharide (LPS) and cyto/chemokines were monitored in supernatants.

Results

Circulating serum levels of CXCL8 and TNFα were raised in all tuberculosis patients, while CCL2 levels were not. There was no difference in spontaneous cytokine secretion from whole blood cells between patients and controls.M. bovisBCG-inducedex vivoCCL2 secretion was significantly greater in pulmonary as compared with both extra-pulmonary tuberculosis patients and endemic controls. In response to LPS stimulation, patients with pulmonary tuberculosis showed increased CCL2 and TNFα responses as compared with the extra-pulmonary group. BCG-, and LPS-induced CXCL8 secretion was comparable between patients and controls.

Conclusion

CCL2 is activated by TNFα and is essential for recruitment of monocytes and T cells to the site of mycobacterial infection. Increased CCL2 activation in pulmonary tuberculosis may result in a stronger cellular response as compared with extra-pulmonary tuberculosis patients, and this may contribute to the localization of infection to the pulmonary site.
A novel Geobacteraceae-specific outer membrane protein J (OmpJ) is essential for electron transport to Fe (III) and Mn (IV) oxides in Geobacter sulfurreducens
Authors: Afkar Eman , Reguera Gemma , Schiffer Marianne , Lovley Derek R
Published: July 2005

Background

Metal reduction is thought to take place at or near the bacterial outer membrane and, thus, outer membrane proteins in the model dissimilatory metal-reducing organism Geobacter sulfurreducens are of interest to understand the mechanisms of Fe(III) reduction in the Geobacter species that are the predominant Fe(III) reducers in many environments. Previous studies have implicated periplasmic and outer membrane cytochromes in electron transfer to metals. Here we show that the most abundant outer membrane protein of G. sulfurreducens, OmpJ, is not a cytochrome yet it is required for metal respiration.

Results

When outer membrane proteins of G. sulfurreducens were separated via SDS-PAGE, one protein, designated OmpJ (o uter m embrane p rotein J), was particularly abundant. The encoding gene, which was identified from mass spectrometry analysis of peptide fragments, is present in other Geobacteraceae, but not in organisms outside this family. The predicted localization and structure of the OmpJ protein suggested that it was a porin. Deletion of the ompJ gene in G. sulfurreducens produced a strain that grew as well as the wild-type strain with fumarate as the electron acceptor but could not grow with metals, such as soluble or insoluble Fe (III) and insoluble Mn (IV) oxide, as the electron acceptor. The heme c content in the mutant strain was ca. 50% of the wild-type and there was a widespread loss of multiple cytochromes from soluble and membrane fractions. Transmission electron microscopy analyses of mutant cells revealed an unusually enlarged periplasm, which is likely to trigger extracytoplasmic stress response mechanisms leading to the degradation of periplasmic and/or outer membrane proteins, such as cytochromes, required for metal reduction. Thus, the loss of the capacity for extracellular electron transport in the mutant could be due to the missing c-type cytochromes, or some more direct, but as yet unknown, role of OmpJ in metal reduction.

Conclusion

OmpJ is a putative porin found in the outer membrane of the model metal reducer G. sulfurreducens that is required for respiration of extracellular electron acceptors such as soluble and insoluble metals. The effect of OmpJ in extracellular electron transfer is indirect, as OmpJ is required to keep the integrity of the periplasmic space necessary for proper folding and functioning of periplasmic and outer membrane electron transport components. The exclusive presence of ompJ in members of the Geobacteraceae family as well as its role in metal reduction suggest that the ompJ sequence may be useful in tracking the growth or activity of Geobacteraceae in sedimentary environments.
Response rate of fibrosarcoma cells to cytotoxic drugs on the expression level correlates to the therapeutic response rate of fibrosarcomas and is mediated by regulation of apoptotic pathways
Authors: Lehnhardt Marcus , Klein-Hitpass Ludger , Kuhnen Cornelius , Homann Heinz Herbert , Daigeler Adrien , Steinau Hans Ulrich , Roehrs Sonja , Schnoor Laura , Steinstraesser Lars , Mueller Oliver
Published: July 2005

Background

Because of the high resistance rate of fibrosarcomas against cytotoxic agents clinical chemotherapy of these tumors is not established. A better understanding of the diverse modes of tumor cell death following cytotoxic therapies will provide a molecular basis for new chemotherapeutic strategies. In this study we elucidated the response of a fibrosarcoma cell line to clinically used cytostatic agents on the level of gene expression.

Methods

HT1080 fibrosarcoma cells were exposed to the chemotherapeutic agents doxorubicin, actinomycin D or vincristine. Total RNA was isolated and the gene expression patterns were analyzed by microarray analysis. Expression levels for 46 selected candidate genes were validated by quantitative real-time PCR.

Results

The analysis of the microarray data resulted in 3.309 (actinomycin D), 1.019 (doxorubicin) and 134 (vincristine) probesets that showed significant expression changes. For the RNA synthesis blocker actinomycin D, 99.4% of all differentially expressed probesets were under-represented. In comparison, probesets down-regulated by doxorubicin comprised only 37.4% of all genes effected by this agent. Closer analysis of the differentially regulated genes revealed that doxorubicin induced cell death of HT1080 fibrosarcoma cells mainly by regulating the abundance of factors mediating the mitochondrial (intrinsic) apoptosis pathway. Furthermore doxorubicin influences other pathways and crosstalk to other pathways (including to the death receptor pathway) at multiple levels. We found increased levels of cytochrome c, APAF-1 and members of the STAT-family (STAT1, STAT3), while Bcl-2 expression was decreased. Caspase-1, -3, -6, -8, and -9 were increased indicating that these proteases are key factors in the execution of doxorubicin mediated apoptosis.

Conclusion

This study demonstrates that chemotherapy regulates the expression of apoptosis-related factors in fibrosarcoma cells. The number and the specific pattern of the genes depend on the used cytotoxic drug. The response rates on the gene expression level, i.e. the number of genes regulated by the drugs actinomycin D, doxorubicin and vincristine, correlate to the clinical effectiveness of the drugs. Doxorubicin seems to exert its cytotoxic mechanism by regulating genes, which are involved in several different apoptosis regulating pathways. The exact knowledge of the genes affected by the drugs will help to understand the diverse modes of soft tissue sarcoma cell death in response to cytotoxic therapies.
Global gene expression analysis in time series following N-acetyl L-cysteine induced epithelial differentiation of human normal and cancer cells in vitro
Authors: Gustafsson Anna C , Kupershmidt Ilya , Edlundh-Rose Esther , Greco Giulia , Serafino Annalucia , Krasnowska Eva K , Lundeberg Thomas , Bracci-Laudiero Luisa , Romano Maria-Concetta , Parasassi Tiziana , Lundeberg Joakim
Published: July 2005

Background

Cancer prevention trials using different types of antioxidant supplements have been carried out at several occasions and one of the investigated compounds has been the antioxidant N-acetyl-L-cysteine (NAC). Studies at the cellular level have previously demonstrated that a single supplementation of NAC induces a ten-fold more rapid differentiation in normal primary human keratinocytes as well as a reversion of a colon carcinoma cell line from neoplastic proliferation to apical-basolateral differentiation [1]. The investigated cells showed an early change in the organization of the cytoskeleton, several newly established adherens junctions with E-cadherin/β-catenin complexes and increased focal adhesions, all features characterizing the differentiation process.

Methods

In order to investigate the molecular mechanisms underlying the proliferation arrest and accelerated differentiation induced by NAC treatment of NHEK and Caco-2 cells in vitro, we performed global gene expression analysis of NAC treated cells in a time series (1, 12 and 24 hours post NAC treatment) using the Affymetrix GeneChip™ Human Genome U95Av2 chip, which contains approximately 12,000 previously characterized sequences. The treated samples were compared to the corresponding untreated culture at the same time point.

Results

Microarray data analysis revealed an increasing number of differentially expressed transcripts over time upon NAC treatment. The early response (1 hour) was transient, while a constitutive trend was commonly found among genes differentially regulated at later time points (12 and 24 hours). Connections to the induction of differentiation and inhibition of growth were identified for a majority of up- and down-regulated genes. All of the observed transcriptional changes, except for seven genes, were unique to either cell line. Only one gene, ID-1, was mutually regulated at 1 hour post treatment and might represent a common mediator of early NAC action.

The detection of several genes that previously have been identified as stimulated or repressed during the differentiation of NHEK and Caco-2 provided validation of results. In addition, real-time kinetic PCR analysis of selected genes also verified the differential regulation as identified by the microarray platform.

Conclusion

NAC induces a limited and transient early response followed by a more consistent and extensively different expression at later time points in both the normal and cancer cell lines investigated. The responses are largely related to inhibition of proliferation and stimulation of differentiation in both cell types but are almost completely lineage specific. ID-1 is indicated as an early mediator of NAC action.