bluuebunny/crossref_metadata_2025 huggingface dataset:
PARALLEL CHANGES IN EXTRACELLULAR MATRIX PROTEIN GENE EXPRESSION, BONE FORMATION AND BIOMECHANICAL PROPERTIES IN AGING RAT BONE
Authors: Buhl Kathleen M. , Jacobs Christopher R. , Turner Russell T. , Evans Glenda L. , Farrell Peter A. , Donahue Henry J.
Published: January 2003

The effect of aging on long bone mechanical properties and bone formative capacity was characterized in the male Fisher 344 rat. The femurs of rats from three age groups (4 mo., 12 mo. and 28 mo.) were tested in three-point bending to determine their structural properties. The apparent material properties were then calculated by adjusting for bone geometry. Bone formation was assessed by dynamic histomorphometry of both cortical and cancellous bone as well as by Northern blot analysis for the expression of the osteoblast phenotypic proteins osteopontin (OP), osteocalcin (OC), type I collagen (COL) and alkaline phosphatase (AP). Aging resulted in a decline in the apparent material properties that was associated with a compensatory alteration of bone geometry that preserved structural strength and stiffness. Histomorphometric analysis revealed significant age-related decreases in cancellous bone volume, trabecular number and increased trabecular separation suggesting the existence of senile osteopenia in the proximal tibia of the male Fisher 344 rat. A significant decline in bone formation rate (BFR), but not mineral apposition rate, suggests that a reduction in osteoblast number, but not osteoblast activity, contributes to age-related bone loss. The decline in BFR with aging was reflected in a decreased mRNA expression for OP, OC and COL but not AP. Further, the pattern of mRNA expression was consistent with reduced osteoblast differentiation with aging. The present study indicates the age-related decline in material properties of long bones is paralleled by a decrease in osteogenesis.
GENE THERAPY: A NOVEL APPROACH TO TREATMENT OF THE DEGENERATION OF INTERVERTEBRAL DISCS
Authors: Tan Jiangwei , Hu Yougu
Published: January 2003

The degeneration of intervertebral discs is one of the pathophysiological causes of lowback pain which has been seriously disturbing human health at the present, No clinical approach can provide prophylaxis or treatment for disc degeneration. But people are now thinking about gene transfer for the prevention of disc degeneration to reduce the incidence of back pain. This idea originated from the development of molecular biology; the deep understanding of the physiology and biochemistry of the intervertebral discs, and the growing scope of gene therapy. The increasing publications on gene therapy for disc degeneration have shown us the future of this research field, and revealed possible difficulties in the process of the study. This article focuses on several important aspects of gene therapy for disc degeneration.
ABDUCTION MOMENT ARMS OF ROTATOR CUFF TENDONS AND DELTOID MUSCLES AFTER ACROMIOPLASTY AND CORACOACROMIAL LIGAMENT SECTION
Authors: Nakajima T. , Liu J. , An Kai-Nan
Published: January 2003

Scientifically, it has been questioned if the coracoacromial ligament has a significant role of serving as a pulley for the supraspinatus tendon. The purpose of this study was to examine the changes of abduction moment arms of the rotator cuff and deltoid muscle after anterior acromioplasty. In normal condition and after sectioning of the coracoacromial ligament and acromioplasty, abduction moment arms of four cuff tendons and three portions of the deltoid were obtained with four cadaver shoulders by computing the slope of the tendon excursion versus the glenohumeral abduction angle curve using a magnetic tracking device. In intact joints, the abduction moment arms of the supraspinatus increased from 20 mm to 27 mm with the arm abducted from 0° to 30°, which showed a better condition of the glenohumeral abduction. Then, they decreased to 23 mm with arm in 60° abduction. After sectioning of the coracoacromial ligament and acromioplasty less than 4 mm thick, the abduction moment arms of supraspinatus did not increase. This finding suggested that the coracoacromial ligament and acromion, anatomically, did not serve as pulleys for the supraspinatus tendon. However, the abduction moment arm of the middle deltoid decreased after an acromioplasty.
The Dynamics of Merger and Acquisition Waves
Authors: Auster Ellen R. , Sirower Mark L.
Published: January 2003

The past two decades have witnessed the largest merger and acquisition (M&A) waves in history. Yet, the empirical evidence suggests that the perceived financial benefits of M&As often are not realized for corporate acquirers. We build a three-stage conceptual framework to illuminate the dynamics of this mergers and acquisitions wave activity and to help explain the frenzied persistence of this phenomenon despite poor performance results. From this framework, we show key considerations that are often missed in M&A assessments, particularly during a merger wave, and offer advice to ensure that managers make more enlightened M&A decisions.
Living the Life of Another: The Need for Public Guardians of Last Resort
Authors: Teaster Pamela B. , Roberto Karen A.
Published: January 2003

Self-report surveys were sent to preidentified representatives of Adult Protective Services, sheriff's offices, community services boards, state training centers, and state hospitals to assess the need for public guardianship. The agencies estimated the need for a total of 2,881 surrogate decision makers (including powers of attorney and payees) and, in particular, 1,425 guardianships. Events most likely to precipitate guardianship included third-party behavior, mental illness or personal behavior, and cognitive impairments or limitations. Virginia's trajectory of the establishment of explicit public guardianship is highly instructive for states and localities seeking to establish or refine public guardianship statutes. As a result of information obtained from the needs assessment and a companion evaluation of two demonstration projects, the Virginia Public Guardian and Conservator Program became law in 1998.
The Validity of Self-Reports of Physician Use Among the Older Population
Authors: Schmitz Mark F. , Russell Daniel W. , Cutrona Carolyn E.
Published: January 2003

This study assessed the validity of older person self-reports of doctor visits, examining variation in the validity of these reports due to factors commonly used in models of health service use. Data were from a sample of 215 healthy, community-dwelling older persons. Participantswere interviewed three times in person at 6-month intervals. They also completed brief mail questionnaires each month between the personal interviews. Information about physical health status and health service use was obtained from the participants' personal physicians. One-way ANOVA tests of means and multinomial logit analyses indicated those respondents reporting more physician visits were significantly less likely to report the same number of visits as the doctors reported and were more likely to underreport than overreport the number of visits. Among the nonsignificant relationships with reporting style were several measures of health status. Implications of recall period length on the validity of these reports are discussed.
Community-Based Services for the Taking but Few Takers: Reasons for Nonuse
Authors: Strain Laurel A. , Blandford Audrey A.
Published: January 2003

This study examined reasons for not using nine community-based services and characteristics associated with these reasons among a sample of 293 older person–caregiver dyads in a Canadian province. The most frequent reasons were that the older person's health did not necessitate use, family/friends provided assistance, and the caregiver was unaware of the service. Cognitive impairment was associated with not using homemaker and/or cleaning services, in-home nursing services, and home-delivered meals as family/friends provided assistance; higher caregiver burden also emerged as significant for these services and personal care services. Male caregivers and caregivers with less education were more likely to be unaware of the availability of day centers, day hospitals, and formal respite services. Implications for future research and practice are highlighted.
Social Security Reform: Options for the Future
Authors: Quinn Joseph F.
Published: January 2003

Currently anticipated Social Security revenues are inadequate to pay for the benefits promised under the current law. Therefore, some combination of revenue increases and/or benefit decreases or delays is inevitable. This article describes the demographic changes behind these long-run fiscal problems and discusses the types of Social Security reform plans that have been proposed—from modest changes in the parameters of the current system to radical reform through privatization. The article reviews the goals of Social Security and discusses the pros and cons of significant privatization. The author concludes that privatization is definitely not required to save Social Security (much more traditional approaches can do that) and that we should be very careful about radically changing a program that is so important to the economic well-being of the majority of older Americans and that has been so successful and popular for more than 60 years.
A Quantitative Approach to the Process Modeling and Planning in Concurrent Engineering
Authors: Yan Hong-Sen , Wang Zheng , Jiang Min
Published: January 2003

This paper deals with the quantitative modeling and planning of the product development process in concurrent engineering (CE). CE requires that product design and its related process design be carried out concurrently. Many existing CE models highlight the impact of the upstream design on the downstream design. While in our research, a quantitative model of the product development process in CE based on the network of product-process design activity pairs is presented to describe both the impact of the upstream product design on the downstream process design and the process design's ability of discovering the faults in the product design. Based on this model, a method is presented to determine the appropriate concurrency degree between the product and process design activities and estimate the mean duration of product-process design activity pair. Then an approach is proposed to solve the integrated optimization problem of both the allocation of resources and the planning of the product development process in CE. Its objective is to allocate the resources for the product development project reasonably to complete it before the due date, minimize its lead-time and keep the average resource utilization rate above a given level. Unlike other project scheduling problems with pre-determined numbers of the resources allocated for the project, in our research, the numbers of the resources allocated for the project are determined along with the project planning. To solve the problem, a branch-and-bound algorithm is proposed and a heuristic rule is introduced to improve its efficiency. The computational result of an example from an automobile factory shows the effectiveness of the algorithm.
Generalized Self-Efficacy, Holland Theme Self-Efficacy, and Academic Performance
Authors: Lindley Lori D. , Borgen Fred H.
Published: January 2003

The relations between generalized self-efficacy, confidence for the six Holland themes, and academic performance as measured by ACT scores and GPA were examined separately for female and male college students. It was predicted that for both women and men, generalized self-efficacy would be more strongly related to the average of confidence scores for the six Holland themes than to confidence for any single Holland theme. In addition, it was predicted that all forms of self-efficacy would be related to academic performance. Findings revealed a particularly strong relation between generalized self-efficacy and Investigative and Enterprising confidence for both women and men; in addition, for men, generalized self-efficacy was strongly related to Conventional confidence as well. ACT score was related to Investigative confidence for both men and women but not to generalized self-efficacy or confidence for the other Holland themes. However, GPA showed no substantial relations with either form of self-efficacy.
Cross-Cultural Equivalence of the Career Decision-Making Self-Efficacy Scale-Short Form: An Australian and South African Comparison
Authors: Creed Peter A. , Patton Wendy , Watson Mark B.
Published: January 2003

The present study examined the reliability, content and construct validity, and cultural equivalence of the short form of the Career Decision-Making Self-Efficacy Scale-Short Form (CDMSE-SF). In response to calls to conduct studies using the measure with high school-age samples, data were gathered from two samples of high school students, one from Australia and one from South Africa. The findings were in accord with earlier studies in that they failed to find five factors. Three factors were found with each sample; however, these factors were different in each sample and different from those reported in samples of U.S. college students, suggesting cross-cultural differences in the construct. The authors suggest that a more parsimonious version of the CDMSE-SF is possible, the CDMSE-SF does not adequately reflect its theoretical origins, and cultural equivalence cannot be assumed.
Personality and Medical Specialty Choice: A Literature Review and Integration
Authors: Borges Nicole J. , Savickas Mark L.
Published: January 2003

This review examines the literature on personality and medical specialty choice. First, it describes studies categorized by medical specialties that to date have used the same measures: Adjective Check List, California Psychological Inventory, Sixteen Personality Factor Questionnaire, and Myers-Briggs Type Indicator. Then it integrates these results using the framework provided by the Five-Factor Model of personality. This model provides a method to organize the personality descriptors associated with medical specialties and to summarize information in an understandable and meaningful way. Conclusions drawn from the review suggest a loose association between a few personality factors and particular medical specialties. Recommendations for further research on personality and medical specialties encourage shifting from the “variable” to the “person” approach and studying how different personalities succeed in the same specialty.
Development of Body Modification and Excessive Exercise Scales for Adolescents
Authors: Mccabe Marita P. , Vincent Maureen A.
Published: January 2003

The present study was designed to develop a Body Modification Scale (BMS) to measure body change among adolescents and to modify an Excessive Exercise Scale (EES) into a shorter form for adolescents. Two hundred and twenty-one girls and 192 boys from Grades 7 to 10 completed the BMS and the EES. Factor analysis revealed three identical factors for the BMS for girls and boys: weight loss, weight gain, and muscle mass. Two identical factors for girls and boys were also revealed for the EES. Both factor structures were further validated on a separate sample of 286 adolescents (140 girls, 146 boys). The BMS and EES demon-strated excellent reliability (alpha > .86) and high test-retest reliability (alpha > .82) over 1 month. Good concurrent validity was also found for the weight loss factor of the BMS. These findings demonstrate the utility of these two scales for use with adolescents.
Abbreviated Form of the Wechsler Memory Scale–III Faces Subtest
Authors: Migoya Judith , Zimmerman Sarah W. , Golden Charles J.
Published: January 2003

A major criticism of the Wechsler Memory Scale–III Faces subtest is the number of items, which can be daunting and time-consuming for an impaired client or boring for a normal client. An analysis of several versions, with data from a sample of 50 clinical referrals, revealed that a 32-item subtest was best overall. Using this version, 100% (Faces I) and 94% (Faces II) of the predicted raw scores were less than 4 points away from the actual raw scores, whereas 66% (Faces I) and 70% (Faces II) were less than 2 points away. Limitations of this procedure are discussed.
Measuring Socioeconomic Status
Authors: Cirino Paul T. , Chin Christopher E. , Sevcik Rose A. , Wolf Maryanne , Lovett Maureen , Morris Robin D.
Published: January 2003

This study investigated issues related to commonly used socioeconomic status (SES) measures in 140 participants from three cities (Atlanta, Boston, and Toronto) in two countries (United States and Canada). Measures of SES were two from the United States (four-factor Hollingshead scale, Nakao and Treas scale) and one from Canada (Blishen, Carroll, and Moore scale). Reliability was examined both within (interrater agreement) and across (intermeasure agreement) measures. Interrater reliability and classification agreement was high for the total sample (range r = .86 to .91), as were intermeasure correlations and classification agreement (range r = .81 to .88). The weakest agreement across measures was found when families had one wage earner who was female. Validity data for these SES measures with academic and intellectual measures also were obtained. Some support for a simplified approach to measuring SES was found. Implications of these findings for the use of SES in social and behavioral science research are discussed.
Emotional Intelligence and Conflict Resolution: Implications for Human Resource Development
Authors: Jordan Peter J. , Troth Ashlea C.
Published: January 2003

The problem and the solution. There continues to be strong interest regarding the emotional intelligence construct,primarily because of the construct’s potential as a predictor of workplace behavior in organizations. Little research has been conducted, however, that considers the implications of emotional intelligence for organizational change and human resource development in organizations.The study outlined in this article explores the connection between emotional intelligence and preferred styles of conflict resolution and examines the implications for human resource development and micro level organizational change specifically. One hundred and thirty-nine respondents were administered the Workgroup Emotional Intelligence Profile, a measure of group members’ emotional intelligence when working in teams, as well as the Thomas-Kilmann Conflict Model Instrument. The results consistently showed that individuals with high emotional intelligence preferred to seek collaborative solutions when confronted with conflict. Implications for human resource development and organizational change are also discussed.
Analyzing Training from an Emotions Perspective
Authors: Short Darren C. , Yorks Lyle
Published: January 2003

The problem and the solution. Emotions, such as excitement, boredom, frustration, joy, and anger, are frequently present in the training room and are likely to influence the training process and the effectiveness of individual and group learning. How, then, can human resource development professionals use empirical and theoretical literature on emotions to understand the impact of emotions on training? This article summarizes the relevant literature and uses two short scenarios to illustrate its application to the training context.
The Planning Technician as Urban Visionary: Frederick Bigger and American Planning, 1881-1963
Authors: Bauman John F. , Muller Edward K.
Published: January 2003

This article explores Frederick Bigger’s importance to the professionalization of American city planning and to the shaping of Pittsburgh’s urban landscape. Educated as an architect at the University of Pennsylvania and a classmate of Henry Wright’s, Bigger dedicated most of his life to establishing urban planning as a discipline in his birth-place, Pittsburgh. However, as a planning theorist as well as a practitioner, Bigger’s world embraced more than planning administration in the Steel City. He was a founding member of the Regional Planning Association of America who combined a keen knowledge of planning administration with a fervent belief in community planning to serve effectively as an official of the New Deal’s Greenbelt Town program and a consultant for the Federal Housing Program. Frederick Bigger’s life highlights the danger of too narrowly pigeonholing pre-World War II planners as moles or skylarks.
Group Intervention Involving a Client With Chronic Fatigue Syndrome
Authors: Taylor RenéE R. , Jason Leonard A.
Published: January 2003

The following case study outlines results from the assessment and treatment of a 32-year-old African American woman with chronic fatigue syndrome. The case history describes a client who is demoralized as a result of having endured worsening symptomatology for the past 3 years with little help from the health care professionals she has consulted. Following evaluation, the client completed a series of eight empowermentoriented, peer counseling groups. Central issues addressed in treatment included issues surrounding expectations fromhealth care providers, issues of denial versus acceptance, identity integration, and irregular patterns of activity. The case study demonstrates the necessity for an individualized and integrative approach to treatment that addresses both medical and psychological aspects of the illness. Findings indicated that a peer-facilitated group therapy intervention was effective in enabling the client to educate herself and gain some acceptance of her condition, modify negative fatigue-related cognitions, improve self-care, and regulate her activity levels.
Cognitive-Behavioral Treatment of Panic Attacks
Authors: McClanahan Terry Michael , Antonuccio David O.
Published: January 2003

Anxiety affects approximately 30 million Americans at some point in their lives. The most common treatment modalities used to treat the continuum are the administration of psychotropic medications and the application of behavioral therapy. The following case details an adult female who suffered from severe panic attacks for a period of 10 years wherein numerous interventions, including psychotropic medications, had failed to ameliorate her suffering. The patient was treated using the Mastery of Your Anxiety and Panic protocol. Prior to treatment, the patient reported that she experienced an average of seven panic attacks per week, her Beck Anxiety Inventory score was 58, and her Beck Depression Inventory was 23. At the completion of treatment, the patient reported that the number of panic attacks was reduced to one per week. At 4-week, 6-week, and 16-week follow-up, the patient had not experienced any panic attacks.
Psychological Treatment of Slot Machine Pathological Gambling
Authors: Echeburúa Enrique , Fernández-Montalvo Javier
Published: January 2003

In this article, treatment with stimulus control, exposure, and relapse prevention of a patient affected by pathological gambling is described. The patient, a 47-year-old woman, was suffering from this disorder for 5 years. Treatment consisted of nine individual sessions (five sessions of stimulus control and exposure and four sessions of relapse prevention) in a period of 10 weeks. At the end of 1-year follow-up, the patient was much improved, without gambling behavior or associated symptoms, as well as with a greater overall adaptation. Implications of this case for clinical research and practice are discussed.
Psychotherapy in Competition With Culture
Authors: Dwairy Marwan
Published: January 2003

Psychotherapy typically addresses the intrapsychic arena in order to accomplish self-awareness and self-actualization. When dealing with clients froma collective/ authoritarian cultural background, the intrapsychic arena is secondary to the intrafamilial one. Application of psychotherapy that aims to help the collective person express her authentic feelings and uncover repressed contents confronts the collective/authoritarian culture. A case of an Arab woman living in an extreme collective/authoritarian Arab culture exemplifies the helplessness of psychotherapy. In this case, psychotherapy is confronted by three cultural barriers: familial pressure, unindividuated personality, and the client's collective values. The case ended in almost complete withdrawal from psychotherapy to a solution offered by the culture. It suggests that the psychotherapist acknowledge the limitations of psychotherapy and appreciate the role of culture in peoples' lives and to facilitate cultural solutions that are functional, even when they seemunaccept able by therapists' individualistic perspective.
A HYBRID 3-D, TWO-WAY IFD PE MODEL FOR 3-D ACOUSTIC BACKSCATTERING
Authors: ZHU DONG , BJØRNØ LEIF
Published: January 2003

A hybrid three-dimensional (3-D), two-way sound propagation model (FDHB3D) is developed for solving 3-D backscattering problems. The FDHB3D model is based on a 3-D Radius-Marching Algorithm (RMA) incorporating a 2-D Two-way Coupling Approach (TCA) by means of a N×2-D procedure. Within a radius-independent space, a 3-D wave field is marched in the radial direction using the 3-D RMA. At the vertical boundaries, a 3-D reflected field is obtained by solving a 2-D Vertical Boundary Equation (VBE) using the 2-D TCA combined with a N×2-D procedure. Different approximations for the 3-D square root operator are compared. Errors arising from the azimuth discretization are analyzed. Numerical studies are performed to demonstrate the superior performance of the FDHB3D model, and to preliminarily reveal 3-D backscattering mechanisms. Studies show that the FDHB3D model can partly handle the azimuth coupling. It is also demonstrated that the diffraction mechanism dominates the backscattered field when the azimuth coupling is significant, while, the reflection mechanism dominates the backscattered field when the azimuth coupling is weak. It is concluded that the FDHB3D model may be applicable to solve specific 3-D backscattering problems in which the azimuth coupling is weak.
AN OPTIMAL FINITE DIFFERENCE REPRESENTATION FOR A CLASS OF LINEAR PDE'S WITH APPLICATION TO THE HELMHOLTZ EQUATION
Authors: CARUTHERS J. E. , STEINHOFF J. S. , ENGELS R. C.
Published: January 2003

A finite difference procedure for linear partial differential equations is shown to be optimal in the sense that the L2 error norm obtained from interpolating an arbitrarily large set of solutions is minimized. The method is valid for any spatial lattice of discretizing points, however, formal 6th order error equivalence is proven for the special cases of the Helmholtz and Laplace equations for a square 2-D lattice.
CUMULATIVE BIREFRINGENCE EFFECTS OF NANOSECOND LASER PULSES IN DYE-DOPED PLANAR NEMATIC LIQUID CRYSTAL LAYERS
Authors: LUKISHOVA SVETLANA G. , BOYD ROBERT W. , LEPESHKIN NICK , MARSHALL KENNETH L.
Published: January 2003

New cumulative effects in laser-induced birefringence have been observed under 10-Hz-pulse-repetition-rate, nanosecond-duration laser irradiation of azo-dye-doped planar-nematic liquid crystal layers at incident intensities I ~ 1–10 MW/cm2. An irradiation geometry with the incident polarization parallel to the nematic director was used. his geometry does not permit a first-order electric field induced reorientation of the nematic molecules, allowing us to exclude its contribution to the nonlinear response. New laser-induced birefringence effects with a buildup time of several seconds to minutes manifest themselves in:

• the appearance of a polarization component perpendicular to the nematic director;

• two different modes of spatial pattern formation with different patterns for parallel and perpendicular polarization:

(1) At I ~ 1–5 MW/cm2, the perpendicular polarization component forms a four-leaf-clover (a Maltese-like cross) spatial pattern in the far-field from the initial Gaussian spatial intensity distribution. The incident, parallel polarization component forms a round spot with a single ring spatial pattern.

(2) At higher incident intensities (I ~ 5–10 MW/cm2), a second regime of pattern formation is observed in the form of high definition patterns and only for the polarization component parallel to the nematic director.
SELF-WRITTEN WAVEGUIDES IN PHOTOSENSITIVE MATERIALS
Authors: SUKHORUKOV ANDREY A. , SHOJI SATORU , KIVSHAR YURI S. , KAWATA SATOSHI
Published: January 2003

We present an overview of the physics of self-written waveguides created in photosensitive optical materials, including the experimental observations and the corresponding theoretical models for describing the growth of both bright and dark self-written beams. We discuss in more details the properties of self-written waveguides created in photosensitive polymers, which have been discovered in the recent experimental and theoretical studies. The self-writing process is essentially a nonlinear phenomenon, since the temporal dynamics depends on the optical exposure. Under appropriate conditions, permanent large changes in the refractive index are induced along the propagation direction of an optical beam, so that optical channels, or "filaments", appear as waveguides becoming "frozen" in a photosensitive material. We describe the growth of individual filaments as well as the interaction of several filaments, also making a comparison between the physics of self-written waveguides and the concept of spatial optical solitons in self-focusing nonlinear media.
Accuracy of MMPI-A Scales ACK, MAC-R, and PRO in Detecting Comorbid Substance Abuse among Psychiatric Inpatients
Authors: Micucci Joseph A.
Published: January 2003

This study investigated the accuracy of various indices involving the MMPI-A scales, ACK, MAC-R, and PRO in diagnosing substance abuse in a sample of 79 psychiatric inpatients. In the full sample, 89.9% of the cases were accurately classified by at least one of the three scales. The overall accuracy of classification was similar among males, females, Caucasians, and African Americans, although there was a tendency for more false positive misclassifications among males. Profile code type moderated the accuracy of classification with greatest accuracy for code types including Scales 1, 2, 3, 5, or 0 and least accuracy for code types including Scales 4, 6, or 9. ACK, MAC-R, and PRO were better at screening out cases of substance abuse than in accurately identifying those adolescents who were using substances.
Correlation between allogenic grade size and allogenic frequency in sediments
Authors: Allen Percival
Published: January 2003

Working-hypotheses regarding the interpretation of allogenic grade size-frequency correlations are presented and applied to certain petrographical data.
Blocking of malaria parasite development in mosquito and fecundity reduction by midgut antibodies in Anopheles stephensi (Diptera: Culicidae)
Authors: Suneja Amita , Gulia Monika , Gakhar S.K.
Published: January 2003

Rabbits were immunized three times with extracts of Anopheles stephensi midgut. Immunized rabbits showed a high titer of antibodies when characterized by ELISA. We investigated the effect of anti‐mosquito midgut antibodies on mosquito fecundity, longevity, mortality, engorgement, and the development of the malaria parasite in mosquitoes. Fecundity was reduced significantly (38%) and similarly hatchability by about 43.5%. There was no statistically significant effect on mortality, longevity, and engorgement. When the mosquito blood meal contained anti‐midgut antibodies, fewer oocysts of Plasmodium vivax developed in the mosquito midgut and the proportion of mosquitoes becoming infected was significantly reduced. We also found that the midgut antibodies inhibit the development and/or translocation of the sporozoites. Antisera raised against midgut of A. stephensi recognized eight polypeptides (110, 92, 70, 45, 38, 29, 15, 13 kDa) by Western blotting. Cross‐reactive antigens/epitopes present in other tissues of A. stephensi were also examined both by Western blotting and in vivo ELISA. Together, these observations open an avenue for research toward the development of a vector‐based malaria parasite transmission blocking vaccine and/or anti‐mosquito vaccine. Arch. Insect Biochem. Physiol. 52:63–70, 2003. © 2003 Wiley‐Liss, Inc.
Nutritional plasticity of the predatory ladybeetle Harmonia axyridis (Coleoptera: Coccinellidae): Comparison between natural and substitution prey
Authors: Specty Olivier , Febvay Gérard , Grenier Simon , Delobel Bernard , Piotte Christine , Pageaux Jean‐François , Ferran André , Guillaud Josette
Published: January 2003

The predatory coccinellid Harmonia axyridis is a polyphagous species, efficient at controlling certain aphid species and already commercialized in Europe for that purpose. The complete development of this predator can be accomplished using the aphid Acyrthosiphon pisum or Ephestia kuehniella eggs as substitution prey. Biochemical analyses were conducted on the proteins, lipids, and carbohydrates of these two different prey species. E. kuehniella eggs were 2 times richer in amino acids than A. pisum adults (12% of the fresh weight vs. 6%). E. kuehniella eggs were 3 times richer in lipids than the aphids but, on the contrary, the aphids were 1.5 times richer in glycogen. The impact of these two kinds of food on the body composition of the coccinellid was evaluated to appreciate the degree of nutritional plasticity of the coccinellid. The composition of the coccinellids feeding either on E. kuehniella eggs or on aphids was compared for amino acid, fatty acid and glycogen contents, revealing a good capability of H. axyridis to develop on foods that are very different in their biochemical composition. Nevertheless, when fed on aphids, the crude protein content of the predator was reduced and the lipid content decreased by a factor of two, with a change in amino and fatty acid patterns. Some biological parameters, such as larval mortality, adult weight, and fecundity, were modified according to the food eaten. Arch. Insect Biochem. Physiol. 52:81–91, 2003. © 2003 Wiley‐Liss, Inc.
Polydnavirus of Campoletis chlorideae: Characterization and temporal effect on host Helicoverpa armigera cellular immune response
Authors: Yin Lihong , Zhang Cong , Qin Junde , Wang Chenzhu
Published: January 2003

Polydnavirus was isolated from oviduct calyx in the parasitoid wasp Campoletis chlorideae (Hymenoptera: Ichneumonidae), and termed CcIV. The virus particles consist of fusiform nucleocapsids surrounded by two unit membrane envelopes. The DNAs purified from these viruses were found diversified in molecular weight and existed in nonequimolar concentrations. At least 20 different‐sized bands were present after electrophoresis, and they ranged from approximately 3 to 26 kb. Persistence and gene expression of CcIV were examined in parasitized and virus‐injected Helicoverpa armigera larvae. Viral DNA could be detected in the hemocyte of H. armigera at 30 min post‐parasitization (p.p.), and persisted for 6 days. While no viral DNA increase was found, CcIV transcripts were first detected in host hemocytes at day 1 p.p. and continued for 5 days. Similar transcripts were observed in hemocytes from larvae that had been injected with calyx fluid or CcIV 24 h earlier. CcIV viral DNAs hybridized only with certain first‐strand cDNAs from hemocytes, suggesting that only part of the CcIV genome was expressed in H. armigera. The pattern of CcIV gene expression was consistent with that of the inhibition of encapsulation for Sephadex G‐10 and parasitoid eggs by host larvae. The recovery of host immune response at day 4 p.p. indicated that CcIV exhibited a partial and temporal effect on the host immune system and the developing parasitoid appeared to avoid encapsulation via different mechanisms. Arch. Insect Biochem. Physiol. 52:104–113, 2003. © 2003 Wiley‐Liss, Inc.
Purification and cDNA cloning of inducible antibacterial peptides from Protaetia brevitarsis (Coleoptera)
Authors: Yoon, Hye Suk , Lee Chang Seok , Lee Sang Yong , Choi Chung Sik , Lee In Hee , Yeo Sung Moon , Kim Hak R.
Published: January 2003

Three antibacterial peptides, named protaetins 1, 2, and 3, were purified and characterized from immunized larval hemolymph of Protaetia brevitarsis, a fruit tree pest in Korea. Also, protaetin 1 was cloned. Acid extraction, gel filtration, preparative acid‐urea PAGE, and reversed‐phase FPLC were used for purification of peptides. Protaetins 1 and 3 had molecular masses of 7.5 and 12 kDa on Tricine SDS‐PAGE, respectively, and the molecular mass of protaetin 2 was 9,283.95 Da as determined by MALDI‐TOF mass spectrometry. In an antibacterial assay, protaetins showed antibacterial activities against a panel of Gram‐positive and ‐negative bacteria. For the RT‐PCR (reverse transcription polymerase chain reaction) to obtain the complete primary sequence, the primer was designed according to the N‐terminal amino acid sequence of protaetin 1. Amino acid sequence homology of protaetin 1 with holotricin 2, an antibacterial peptide from Holotrichia diomphalia, showed 99% identity. Northern blot analysis showed that the protaetin 1 gene was strongly expressed in the fat body after Escherichia coli injection, but not in normal fat body. Also, it was expressed in the gut, but was much weaker after immunization. Arch. Insect Biochem. Physiol. 52:92–103, 2003. © 2003 Wiley‐Liss, Inc.
The bacterium Xenorhabdus nematophilus depresses nodulation reactions to infection by inhibiting eicosanoid biosynthesis in tobacco hornworms, Manduca sexta
Authors: Park Youngjin , Kim Yonggyun , Putnam Sean M. , Stanley David W.
Published: January 2003

The bacterium, Xenorhabdus nematophilus, is a virulent insect pathogen. We tested the hypothesis that this bacterium impairs insect cellular immune defense reactions by inhibiting biosynthesis of eicosanoids involved in mediating cellular defense reactions. Fifth instar tobacco hornworms, Manduca sexta, produced melanized nodules in reaction to challenge with living and heat‐killed X. nematophilus. However, the nodulation reactions were much attenuated in insects challenged with living bacteria (approximately 20 nodules/larva for living bacteria vs. approximately 80 nodules/larva in insects challenged with heat‐killed bacteria). The nodule‐inhibiting action of living X. nematophilus was due to a factor that was present in the organic, but not aqueous, fraction of the bacterial cultural medium. The nodule‐inhibiting factor in the organic fraction was labile to heat treatments. The immunodepressive influence of the factor in the organic fraction was reversed by treating challenged hornworms with arachidonic acid. The factor also depressed nodulation reactions to challenge with the plant pathogenic bacteria, Pseudomonas putida and Ralstonia solanacearum. These findings indicate that one or more factors from X. nematophilus depress nodulation reactions in tobacco hornworms by inhibiting eicosanoid biosynthesis. Arch. Insect Biochem. Physiol. 52:71–80, 2003. © 2003 Wiley‐Liss, Inc.
Modeling the performance of pilot‐scale countercurrent chromatography: Scale‐up predictions and experimental verification of erythromycin separation
Authors: Booth A.J. , Sutherland I. A. , Lye G. J.
Published: January 2003

Biosynthesis of polyketide antibiotics, such as erythromycin A (EA), can result in the formation of analogues of the main compound that are chemically and structurally extremely similar. The large‐scale purification of these antibiotics by conventional high‐performance liquid chromatography (HPLC) can be prohibitively expensive due to the large volume of both solvent and adsorbent required. This study examines the feasibility of using a novel pilot‐scale countercurrent chromatography (CCC) machine as an alternative to HPLC. CCC is a low‐pressure (typically <4000 kN m−2) liquid–liquid chromatographic technique that allows the separation of solutes on the basis of their partitioning between two immiscible liquid phases. The effects of mobile phase flow rate, column rotational speed, and sample injection volume on the attainable yield and purity of EA were investigated. Our results show that, at a mobile phase flow rate of 40 mL min−1, a rotational speed of 1200 rpm, and an injection volume of 100 mL (10 g total erythromycin), EA could be satisfactorily fractionated with a purity of ∼92% (w/w) and a recovery yield of ∼100% (w/w). The total solute throughput was estimated to be 0.41 kg day−1. More importantly, we demonstrated simple and predictive linear scale‐up of the CCC separation based on data obtained from a single laboratory‐scale CCC chromatogram, and verified this experimentally. The retention time and peak width of the target compound at the pilot scale could be predicted to within 4% for operation at a range of mobile‐phase flow rates and injection volumes. This predictable nature of CCC separations, unlike HPLC methods, can greatly reduce process development times and enable a complete process‐scale operating scenario to be planned. © 2003 Wiley Periodicals, Inc. Biotechnol Bioeng 81: 640–649, 2003.
Parameter scanning ultrafiltration: Rapid optimisation of protein separation
Authors: Ghosh Raja , Wan Yinhua , Cui Zhanfeng , Hale Geoff
Published: January 2003

High‐resolution fractionation of proteins using ultrafiltration is feasible only at highly optimised conditions. Conventional process optimisation methodology demands both time and material. Pulsed sample injection ultrafiltration has been suggested as a rapid process optimisation technique. In the present work the scope of this technique is further extended by “parameter scanning ultrafiltration,” which involves continuous change of a process parameter (e.g., pH, salt concentration). The time and material consumption are thus further reduced. The technique was validated using different proteins and membranes. Sieving coefficients at different pH and salt concentration were compared to those obtained in fixed parameter ultrafiltration experiments. As fractionation case studies the separation of monoclonal antibody from bovine serum albumin and separation of human IgG from human serum albumin were examined. © 2003 Wiley Periodicals, Inc. Biotechnol Bioeng 81: 673–682, 2003.
Cell affinity separations using magnetically stabilized fluidized beds: Erythrocyte subpopulation fractionation utilizing a lectin‐magnetite support
Authors: Putnam David D. , Namasivayam Vijay , Burns Mark A.
Published: January 2003

A magnetically stabilized fluidized bed is used to separate erythrocyte subpopulations. Binding specificity was obtained by immobilizing the lectin Helix pomatia Agglutinin (HpA) or Griffonia simplicifolia I (GSI) onto a magnetite‐containing support. Separation of type A and type O erythrocytes with the lectin HpA was particularly effective, leading to a 94% purity of retained type A erythrocytes. A 3.1 ± 0.6 log removal of type A erythrocytes was also accomplished leading to a 99.7% ± 0.4% purity and 95% ± 7% yield of type O erythrocytes in the collected effluent. Elution of the purified cells was accomplished using fluidization in the presence of a sugar competing for the lectin–erythrocyte binding site. A mathematical model based on the depth filtration model of Putnam and Burns (Chem Eng Sci 1997;52(1):93–105) was extended to include multicomponent cell adhesion. This filtration model is the first to take into account the finite binding capacity of the chromatographic support and is used to characterize the cell binding behavior and to determine optimal parameters and conditions that lead to high capacities and selectivities. Model parameter values and observations from in situ adsorption studies suggest that the non‐spherical shape of the magnetite‐based support allows for a more efficient utilization of the support surface area than the spherical shape. Using a 1.5‐cm diameter laboratory column and realistic parameter values, the processing rates of the system are predicted to be at least an order of magnitude greater than the 108/h cells that can typically be processed in packed bed cell affinity chromatography (CAC) systems. © 2003 Wiley Periodicals, Inc. Biotechnol Bioeng 81: 650–665, 2003.
Use of the two‐liquid phase concept to exploit kinetically controlled multistep biocatalysis
Authors: Bühler Bruno , Bollhalder Irene , Hauer Bernhard , Witholt Bernard , Schmid Andreas
Published: January 2003

The two‐liquid phase concept was used to develop a whole cell biocatalytic system for the efficient multistep oxidation of pseudocumene to 3,4‐dimethylbenzaldehyde. Recombinant Escherichia coli cells were employed to express the Pseudomonas putida genes encoding xylene monooxygenase, which catalyzes the multistep oxygenation of one methyl group of toluene and xylenes to corresponding alcohols, aldehydes, and acids. A fed‐batch based two‐liquid phase bioconversion was established with bis(2‐ethylhexyl)‐ phthalate as organic carrier solvent and a phase ratio of 0.5; the product formation pattern, the impact of the nutrient feeding strategy, and the partitioning behavior of the reactants were studied. On the basis of the favorable conditions provided by the two‐liquid phase system, engineering of the initial pseudocumene concentration allowed exploiting the complex kinetics of the multistep reaction for the exclusive production of 3,4‐dimethyl‐ benzaldehyde. Further oxidation of the product to 3,4‐dimethylbenzoic acid could be inhibited by suitable concentrations of pseudocumene or 3,4‐dimethylbenzyl alcohol. The optimized biotransformation setup includes a completely defined medium with high iron content and a nutrient feeding strategy that avoids severe glucose limitation as well as high inhibitory glucose levels. Using such a system on a 2‐liter scale, we were able to produce, within 14.5 h, 30 g of 3,4‐dimethylbenzaldehyde as predominant reactant in the organic phase and reached a maximal productivity of 1.6 g per liter liquid volume per hour. The present study implicates that the two‐liquid phase concept is an efficient tool to exploit the kinetics of multistep biotransformations in general. © 2003 Wiley Periodicals. Biotechnol Bioeng 81: 683–694, 2003.