bluuebunny/crossref_metadata_2025 huggingface dataset:
Patient Problems, Advanced Practice Nurse (APN) Interventions, Time and Contacts Among Five Patient Groups
Authors: Brooten Dorothy , Youngblut JoAnne M. , Deatrick Janet , Naylor Mary , York Ruth
Published: April 2004

Purpose: To describe patient problems and APN interventions in each of five clinical trials and to establish links among patient problems, APN interventions, APN time and number of contacts, patient outcomes, and health care costs.

Design and Methods: Analysis of 333 interaction logs created by APNs during five randomized controlled trials: (a) very low birthweight infants (n=39); (b) women with unplanned cesarean birth (n=61), (c) high‐risk pregnancy (n=44), and (d) hysterectomy (n=53); and (e) elders with cardiac medical and surgical diagnoses (n=139). Logs containing recordings of all APN interactions with participants, APN time and type of patient contact were content analyzed with the smallest phrase or sentence representing a “unit.” These units were then classified using the Omaha Classification System to determine patient problems and APN interventions. Groups were compared concerning total amount of APN time, number of contacts per patient, and mean length of time per APN contact. All studies were conducted in the United States.

Findings: Groups with greater mean APN time and contacts per patient had greater improvements in patients' outcomes and greater health care cost savings. Of the 150,131 APN interventions, surveillance was the predominant APN function in all five patient groups. Health teaching, guidance, and counseling was the second most frequent category of APN intervention in four of the five groups. In all five groups, treatments and procedures accounted for < 1% of total APN interventions. Distribution of patient problems (N=150,131) differed across groups reflecting the health care problems common to the group.

Conclusions: Dose of APN time and contacts makes a difference in improving patient outcomes and reducing health care costs. Skills needed by APNs in providing transitional care include well‐developed skills in assessing, teaching, counseling, communicating, collaborating, knowing health behaviors, negotiating systems, and having condition‐specific knowledge about different patient problems.
Factors Influencing Quality of Life in People with Chronic Illness in Korea
Authors: Han KuemSun , Lee PyoungSook , Lee SookJa , Park EunSook
Published: April 2004

Purpose: To identify factors influencing quality of life based on health‐promoting behavior in patients with chronic illness.

Design and Methods: This descriptive study was conducted over 8 months in 2001 on 1,748 chronic adult outpatients at a university hospital in Seoul, Korea. Study variables and instruments were health perception, perceived benefits of action, perceived barriers to action, self‐esteem, self‐efficacy, social support, commitment of planned action, activity‐related affect, health‐promoting behavior, and quality of life.

Results: The data indicated a statistically significant positive correlation among healthpromoting behavior, perceived benefits of action, self‐efficacy, social support, self‐esteem, health perception, activity‐related affect, and quality of life. A statistically significant negative correlation was found between perceived barriers to action and quality of life. Stepwise multiple regression showed that the most powerful predictor of quality of life was healthpromoting behavior. The combination of health‐promoting behavior, activity‐related affect, self‐esteem, health perception, commitment to planned action, social support, and perceived barriers to action accounted for 57% of the variance in quality of life.

Conclusions: Multiple social, psychological, and health‐related factors were associated with quality of life.
Predictors of Condom Use Among Adolescent Thai Vocational Students
Authors: Thato Sathja , Charron‐Prochownik Denise , Dorn Lorah D. , Albrecht Susan A. , Stone Clement A.
Published: April 2004

Purpose: To describe the prevalence of premarital sexual behavior and condom use, and to identify predictors of condom use using the expanded health belief model (EHBM) among vocational students in Bangkok, Thailand.

Methods: A cross‐sectional correlational design was used with a cluster‐based sample of 425 students aged 18 to 22 years from eight randomly selected private vocational schools in Bangkok. Anonymous self‐report questionnaires were used to collect the data. Stepwise multiple regression was conducted to identify predictors of condom use.

Results: Overall, 49.9% of participants were sexually active, 64.8% of men and 32% of women. Of the sexually active participants, only 6.3% reported using condoms every time when having sex in the beginning of the relationship, and 10.2% during the last few times. Twenty‐four percent of sexually active participants had unplanned pregnancies, and 7% had sexually transmitted diseases (STDs). The predictive model of condom use consisted of perceived benefits from using condoms; interactions between intention to use condoms and gender: knowledge of STDs, HIV, AIDS, pregnancy and peer norms; and alcohol use and age. Adjusting for modifying factors, the predictor set explained 27% of the variance in condom use.

Conclusions: Most of this sample of sexually active Thai vocational students practiced unsafe sex, and many had unplanned pregnancies and STDs. The EHBM provided a modest predictive model of condom use.
A Theoretical Explanation for Previously Infertile Mothers' Vulnerability to Depression
Authors: Olshansky Ellen
Published: April 2004

Purpose: To present a theoretical approach to understanding the potential vulnerability to depression in previously infertile new mothers.

Methods: This approach was developed by synthesizing results of a series of grounded theory studies of experiences of infertility and pregnancy and of parenting after infertility. These results were further synthesized with the relational cultural theory (RCT).

Findings: Previously infertile new mothers have experienced repeated and sustained interferences with significant relationships over the course of their infertility, which could lead to depression.

Conclusions: Implications of this theoretical perspective include: (a) it is a new approach to understanding a significant and sometimes minimized issue in women's health; (b) it is a basis for designing an intervention for women coping with infertility and its aftermath; and (c) it might be applied to other women's health issues.
Professional Values Held by Baccalaureate and Associate Degree Nursing Students
Authors: Martin Pam , Yarbrough Susan , Alfred Danita
Published: April 2004

Purpose: To determine the congruency in value orientation of graduating students in baccalaureate and associate degree programs.

Design and Methods: A survey design with a convenience sample of 1,450 graduating nursing students from all baccalaureate and associate degree nursing programs in Texas. Data were collected using the Nurses Professional Values Scale (NPVS). Descriptive and parametric statistics were used for analysis.

Findings: ADN and BSN students did not differ significantly on the NPVS total score, however, ADN students scored higher on 5 of the 11 subscales than did their BSN counterparts. Men from both programs scored significantly lower than did women on the total scale and all subscales. Ethnic groups differed on the responses to three of the subscales representing nurses' values: respect for human dignity, safeguarding the client and public, and collaborating to meet public health needs.

Conclusions: Professional values in graduating nursing students were significantly related to sex and ethnicity, regardless of educational program. Nursing faculty members are challenged to address these differences during the educational process and mentoring of students.
Issues and Dilemmas in Conducting Research with Vulnerable Home Hospice Participants
Authors: Dobratz Marjorie C.
Published: April 2004

Purpose: To describe issues and dilemmas related to nonparticipation, attrition, and needs for assistance in research with vulnerable home hospice participants.

Design and Methods: Retrospective analysis, with descriptive statistics of the frequency of issues and dilemmas that occurred in a research study with a vulnerable population.

Findings: From a group of 113 potential participants, 16 (14.1%) people who gave initial consent were unable to participate or were lost to the study (subset I) for the following reasons: unable to give informed consent, cognitive disturbance, and physical distress. Of the 97 participants who completed testing, 28 (28.8%) required assistance (subset II) because of poor vision, physical weakness, and other physical impairments.

Conclusions: Loss of potential participants limited this study and hampered effect size. Research with home hospice patients required careful assessment for symptoms that precluded informed consent. Issues with cognition indicated need for a tool to assess mental acuity. Although several participants required assistance, those who completed testing expressed gratitude at being able to contribute information that they believed would benefit others.
Home Care Nurses' Descriptions of Important Agency Attributes
Authors: Flynn Linda , Deatrick Janet A.
Published: April 2004

Purpose: To identify attributes of home care agencies described by nurses as important to their professional practice and job satisfaction.

Design: Seven focus groups with home health care staff nurses were conducted at 6 home care agencies located in three states in the Mid‐Atlantic region of the United States. A total of 58 home care nurses participated in the study.

Methods: Transcriptions of tape‐recorded focus groups were subjected to open and axial coding techniques.

Results: Six major categories and eight subcategories of organizational attributes described by home care nurses as important to the support of their practice and job satisfaction were identified.

Conclusions: Attributes described by home health nurses were not only similar to those described by hospital‐based nurses as reported in the ‘magnet hospital’ literature, but they also were consistent with key concepts described in theories of professional workforce organization. Findings provide insight into developing workplace environments to support home care nurses.
Extrusion analysis of a bolt-reinforced tunnel face with finite ground-bolt bond strength
Authors: Wong H , Trompille V , Dias D
Published: April 2004

In this paper a new analytical model is proposed to analyse the displacement behaviour of a tunnel face reinforced by bolts, using the homogenization approach for periodic media. Based on previous works, this new model was developed to take into account a finite bond strength of the groutsoil interface, which is more realistic than the perfect bonding assumption. The interface behaviour is simulated by an elastic  perfectly plastic constitutive law. The interface sliding occurs when the shear stress reaches the bond strength. This new feature allows for a more correct estimate of the bolt tension and the quantitative contribution of the bolt to reducing displacement of the ground surface. Despite using less restrictive hypotheses, the solution process remains sufficiently simple, thus preserving the analytical character of the solution. This new analytical model has been validated by three-dimensional (3D) numerical calculations using the finite difference code FLAC3D and by comparing its predictions with in situ data from the Tartaiguille Tunnel construction project, which forms part of the Mediterranean TGV (high speed railway) network. The developed approach results in simple and efficient design tools, which are very useful at the preliminary design stage of a project.Key words: tunnels, soilstructure interaction, reinforcement, numerical modelling and analysis, deformation, plasticity.
In situ characterization of land reclaimed using big clay lumps
Authors: Karthikeyan Muthusamy , Dasari Ganeswara Rao , Tan Thiam-Soon
Published: April 2004

Dredging works in the sea and excavations in built-up areas produce large quantities of clay lumps in Singapore. The use of these clay lumps for land reclamation is an attractive proposition for solving the problem of finding dumping grounds for disposal and at the same time creating new land. When these big clay lumps are used for reclamation, however, the land will have large initial interlump voids. These large interlump voids may not close completely, even with surcharge, and may lead to excessive settlement when a structure is constructed on land reclaimed using this material. Two major engineering issues related to the use of clay lumps for reclamation are the size of interlump voids at the end of consolidation and the engineering properties of such ground. The need to know the ultimate state of the ground reclaimed using large clay lumps is critical to its acceptance as a viable fill material. To our knowledge, data on the ultimate state of such reclaimed lands are not available. An extensive site investigation was performed at a test site on the island of Punggol Timor in Singapore, which was reclaimed about 12 years ago using big dredged clay lumps. The thrust of the investigation is to evaluate the present state of the reclaimed land, with special emphasis on identifying the size of current interlump voids. The radioisotope cone penetration test was employed to measure the in situ density of the site. The site investigation also included high-quality soil sampling and laboratory testing to determine the present strength and deformation characteristics of the reclaimed land. The results indicate that the initially large interlump voids have been reduced to the size of intralump voids. However, the layer formed from clay lumps is heterogeneous and exhibits variable engineering properties. Key words: in situ characterization, land reclamation, radioisotope cone penetration tests, wet density, big clay lumps.
Novel toe driving for thin-walled piles and performance of fiberglass-reinforced polymer (FRP) pile segments
Authors: Sakr Mohammed , Naggar M Hesham El , Nehdi Moncef
Published: April 2004

Despite the rapidly growing use of pile foundations, it is presently difficult to assure the integrity and uniformity of the cross-sectional area of cast-in-place piles when using normal concrete. Cavities and soil encroachments leading to soil pockets can jeopardize their load-bearing capacity. Moreover, corrosion in reinforced concrete and steel shell piles has been very costly, exceeding US$2 billion in annual repair costs in the United States alone. To address these two challenges, extensive research has been underway at the University of Western Ontario to develop novel technology for the construction of piles. Self-consolidating concrete (SCC), a material that flows under gravity and assures the integrity of piles, is cast into fiberglass-reinforced polymer (FRP) tubes that provide corrosion-resistant reinforcement. A toe driving technique was developed to install the empty FRP shells into the soil, and SCC is subsequently cast into the shells. Driving tests using this new technique were carried out on large-scale model FRP and steel pipe piles installed in dense dry sand enclosed in a pressure chamber. FRPSCC and steel closed-end piles were also driven using conventional piling at the pile head. Static load tests were conducted on the various pile specimens under different vertical and horizontal confining pressures. The pile specimens were instrumented to investigate their dynamic behaviour under driving and their response to static compressive, uplift, and lateral loading. It is shown that the toe driving technique is very suitable for installing FRP piles in dense soils. Results from the driving tests and static load test indicate that FRPSCC hybrid piles are a very competitive and attractive option for the deep foundations industry.Key words: FRP, self-consolidating concrete, piles, pile drivability, toe driving, axial load, uplift load, lateral load, large-scale modeling, shaft resistance, dense sand.
Coupled multi-ion electrodiffusion analysis for clay soils
Authors: Jungnickel Christian , Smith David , Fityus Stephen
Published: April 2004

For a well-engineered compacted clay landfill liner, diffusive transport through the liner is the main mass transport mechanism from the landfill. Therefore, accurate estimates of diffusion coefficients for clay liners are essential for the engineering design of liner systems. A long-standing problem has been the effect of ion pairing on the estimation of diffusion coefficients for multicomponent ionic solutions migrating through clay liners. This paper considers the solution of a fully coupled set of transport equations describing the simultaneous diffusion of several ion species through a clayey soil. The analysis takes into account the diffusion coefficient for each ion species, ion pairing (as required by electroneutrality of the solution), and time-dependent first-order ion and (or) ligand exchange reactions with the clay particles. The behaviour of a double-reservoir diffusion cell, often employed for the estimation of diffusion coefficients in the laboratory, is analyzed using the coupled transport model. A detailed theoretical analysis is made of sodium fluoride transport through saturated kaolinitic clay.Key words: multi-ion diffusion, finite element analysis, reactive transport, kaolinite, double-reservoir diffusion cell.
Laboratory study of soilnail interaction in loose, completely decomposed granite
Authors: Junaideen S M , Tham L G , Law K T , Lee C F , Yue Z Q
Published: April 2004

The technique of soil nailing is seldom used in stabilizing loose fill slopes because there is a lack of understanding of the interaction behaviour of nails in loose fills. A large-scale laboratory apparatus has been built to study the soilnail interaction in loose fill materials. Pullout tests were performed in a displacement-rate-controlled manner on steel bars embedded in loose, completely decomposed granitic soils. The loaddisplacement curves have distinct peak values followed by a sharp decrease in the pullout force. The test results also show that the normal stress acting on the nail changes because of the volume-change tendency and arching effect of the soil being sheared around the nail. The post-peak decrease in the pullout force is mainly due to the reduction in the normal stress caused by the arching effect of soil around the nail. The conventional method of analysis tends to give a low interface friction angle and high interface adhesion. The correct interface parameters can be determined by taking the changes in the normal stress acting on the nail into account.Key words: arching effect, interface friction angle, laboratory test, loose fill, pullout resistance, soilnail interaction.
Introduction: Ecology and the Central Nervous System
Authors: Giraldeau Luc-Alain
Published: April 2004

Behavioral ecology, the study of the survival value or function of behavior, has developed for a time by confining cognition to convenient black boxes that were assumed to be rigged by natural selection to direct an animal to the right decision for a given set of circumstances. However, the interpretation of test results concerning functional hypotheses about behavior depends crucially on assumptions made about their ability to collect and process information: cognition. Clearly, progress in behavioral ecology requires that the cognitive black boxes be opened and studied. This need coincides with an explosive growth of interest in animal cognition that has promoted and enhanced the level of interaction between behavioral ecologists and animal cognition scientists. The result promises to be profitable to the extent that it will raise interest and research in a number of new areas such as the costs in terms of survival value of evolving increased cognitive capacity or even the possibility of exploring brain morphology using a functional approach.
Causes and Consequences of Limited Attention
Authors: Dukas Reuven
Published: April 2004

This review focuses on the evolutionary causes and consequences of limited attention, defined as the restricted rate of information processing by the brain. The available data suggest, first, that limited attention is a major cognitive constraint determining animals’ search for cryptic food, and, second, that limited attention reduces animals’ ability to detect predators while involved in challenging tasks such as searching for cryptic food. These two effects of limited attention probably decrease animal fitness. Furthermore, a simulated evolutionary study provides empirical support for the prediction that focused attention by predators selects for prey polymorphism. The neurobiological mechanisms underlying limited attention have been widely studied. A recent incorporation of that mechanistic knowledge into an ecological model suggests that limited attention is an optimal strategy that balances effective yet economical search for cryptic objects. The review concludes with a set of testable predictions aimed to expand the currently limited empirical knowledge on the evolutionary ecology of limited attention.
Spatial Learning and Memory in Birds
Authors: Healy Susan D. , Hurly T. Andrew
Published: April 2004

Behavioral ecologists, well versed in addressing functional aspects of behavior, are acknowledging more and more the attention they need also to pay to mechanistic processes. One of these is the role of cognition. Song learning and imprinting are familiar examples of behaviors for which cognition plays an important role, but attention is now turning to other behaviors and a wider diversity of species. We focus here on work that investigates the nature of spatial learning and memory in the context of behaviors such as foraging and food storing. We also briefly explore the difficulties of studying cognition in the field. The common thread to all of this work is the value of using psychological techniques as tools for assessing learning and memory abilities in order to address questions of interest to behavioral ecologists.
Neural Constraints on the Complexity of Avian Song
Authors: DeVoogd Timothy J.
Published: April 2004

Why do birds sing? In many species, because the song attracts or retains a mate. Why do females pay attention? This paper reviews evidence that females may do so because male song can be an honest indicator of attributes of a male’s brain that could contribute to his fitness or that of his young. Male songbirds learn and produce their songs using a set of brain regions collectively known as the song system. The learning has distinct auditory and motor components, and current data suggest that the neural changes that encode these forms of learning primarily occur in different subdivisions of the song system. There are positive correlations between song complexity and the volume of motor song system nucleus HVC, both between and within species. The correlations appear to arise because individual differences in volume lead to differences in capacity for learning. The differences in HVC volume are correlated with differences in the volumes of other song system components and with the volume of the forebrain. They are heritable. Thus, a complex song can be a signal to a female of immediate fitness (the male has a larger brain) and ultimate fitness (he has attractive characteristics that will be passed on to progeny).
Cyclodestructive Procedures
Authors: Fankhauser Franz , Kwasniewska Sylwia
Published: April 2004

Methods used in laser destructive procedures are detailed. While in noncontact procedures laser energy is delivered via the optics of a slitlamp, often enhanced by contact lenses, the contact method takes advantage of optical fibers for the delivery of energy. Endpieces such as hemispherical or microlens probes enhance the cyclodestructive effect and/or allow the dose of laser energy to be reduced. Laser energy may also be delivered under direct view by endoscopic systems. Advances in laser cyclodestruction are possible by studying the physical effects.
Fluorophotometric Evaluation of Blood-Retinal Barrier Permeability in Patients with Essential Hypertension
Authors: Pogrzebielski A. , Lubaszewski W. , Starzycka M. , Kawecka-Jaszcz K.
Published: April 2004

Aim: The fluorophotometric evaluation of the blood-retinal barrier (BRB) integrity in patients with essential hypertension (EH) without signs of BRB damage. Material and Methods: 55 subjects participated in the study: 36 patients with EH and 19 normotensive healthy volunteers; 22 men and 33 women. The protocol included ophthalmic examination, fluorescein angiography, fluorophotometry, laboratory tests (total cholesterol, LDL and HDL cholesterol, triglycerides, fibrinogen, serum creatinine concentration, fasting glucose concentration, oral glucose test), urinary cotinine concentration measurement and cotinine-creatinine ratio (CCR) calculation. Results: BRB permeability (PBRB) in patients with EH was significantly higher than in the control group (2.24 ± 0.68 vs. 1.64 ± 0.64 nm/s; p = 0.003). In hypertensive patients with CCR >50 ng/mg, the PBRB was significantly higher than the PBRB in healthy volunteers not exposed to smoke (2.32 vs. 1.68 nm/s; p < 0.05). Conclusions: The PBRB in patients with EH is significantly higher than that in the normotensive control group, which shows the damaging effect of EH on the BRB.
Photodynamic Therapy with Verteporfin for Polypoidal Choroidal Vasculopathy of the Macula
Authors: Lee Sung Chul , Seong Youl Seok , Kim Sung Soo , Koh Hyung Jun , Kwon Oh Woong
Published: April 2004

Purpose: Indications for photodynamic therapy (PDT) have increased from age-related macular degeneration with choroidal neovascularization (CNV), containing more than 50% of the classic component, to occult CNV, myopic CNV and CNV due to ocular histoplasmosis syndrome. In the present study, the effect of PDT with verteporfin was examined in polypoidal choroidal vasculopathy (PCV) of the macula. Methods: PDT was performed in 9 eyes with PCV of the macula. Fundus examination, fluorescein angiography, and indocyanine green angiography were performed before PDT and 3 months after PDT in all eyes. Optical coherence tomography was performed in 6 eyes. Results: After the initial PDT, visual acuity was stabilized or improved in 8 eyes (89%), polypoid elements were obliterated in 7 eyes (78%), and vascular nets were reduced in 8 eyes (89%). Of 6 eyes that received optical coherence tomography, pigment epithelium detachment was reduced or disappeared in all eyes except 1, which developed a disciform scar. An additional PDT was performed in 4 eyes to decrease vascular leakage. During the follow-up period of 3–18 months, no reactivation of PCV was observed. Conclusion: PDT offers an effective way of treating PCV of the macula, by obliterating polypoid elements of the PCV. However, long-term follow-up is needed.
Influence of the Antiseptic Agents Polyhexanide and Octenidine on FL Cells and on Healing of Experimental Superficial Aseptic Wounds in Piglets
Authors: Kramer A. , Roth B. , Müller G. , Rudolph P. , Klöcker N.
Published: April 2004

The main target of the combination of octenidine with phenoxyethanol (Octenisept®) is the antisepsis of acute wounds, whereas polyhexanide combined with polyethylene glycol in Ringer solution (Lavasept®) is the agent of choice for antisepsis of chronic wounds and burns. Because comparative data for both agents on the effects on wound healing are lacking, we investigated the influence of preparations based on polyhexanide and octenidine versus placebo (Ringer solution) in experimental superficial aseptic skin wounds (n = 108) of 20 mm diameter, using a double-blind, randomised, stratified, controlled, parallel-group design in piglets. Computerised planimetry and histopathological methods were used for the assessment of wound healing. Histologically, no significant differences could be verified at any time between the 3 groups. However, in the early phase (day 9 after wounding), the octenidine-based product retarded wound contraction to a significantly greater extent than placebo and polyhexanide, whereas in the later phase (days 18 and 28), polyhexanide promoted contraction significantly more than did placebo and octenidine. The consequence is complete wound closure after 22.9 days using polyhexanide, in comparison to the placebo after 24.1 days (p < 0.05) and octenidine after 28.3 days (no statistical difference to placebo). This may be explained by the better tolerance of polyhexanide in vitro, which was demonstrated with dose and time dependence in cytotoxicity tests on human amnion cells.
Identification of Benzene Metabolites in Dermal Fibroblasts as Nonphenolic: Regulation of Cell Viability, Apoptosis, Lipid Peroxidation and Expression of Matrix Metalloproteinase 1 and Elastin by Benzene Metabolites
Authors: Philips N. , Burchill D. , O’Donoghue D. , Keller T. , Gonzalez S.
Published: April 2004

The skin is exposed to benzene and its derivatives, prevalent environmental chemicals. They may impair the structural integrity of the skin by increased expression of matrix metalloproteinase 1 (MMP-1; degrades structural collagen) and elastin, synthesized primarily by the dermal fibroblasts. We examined the metabolism of benzene in dermal fibroblasts and identified the benzene metabolites as toluene, benzaldehyde, aniline and benzoic acid. These metabolites were not toxic to the cells with regard to cell viability, apoptosis and lipid peroxidation, unlike the phenolic benzene metabolites (hydroquinone, t-butyl hydroquinone and phenol) or hydrogen peroxide. Toluene and phenol, which compose cigarette smoke, and benzaldehyde stimulated MMP-1 and/or elastin expression. In summary, the dermal fibroblasts metabolize benzene to nonphenolic metabolites that are less toxic to the cellular components than the phenolic benzene derivatives. Toluene, benzaldehyde and phenol can directly cause facial wrinkling and impaired structural integrity by upregulating MMP-1 and/or elastin.
Adenovirus-Mediated Expression of Brain-Derived Neurotrophic Factor Protects Spiral Ganglion Neurons from Ototoxic Damage
Authors: Nakaizumi Toshihiko , Kawamoto Kohei , Minoda Ryosei , Raphael Yehoash
Published: April 2004

Hair cell loss, the most common cause of deafness, is often associated with auditory nerve degeneration. Our goal was to determine the influence of combined ciliary-derived neurotrophic factor (CNTF) and brain-derived neurotrophic factor (BDNF) gene therapy on the survival of spiral ganglion neurons (SGNs) after elimination of inner hair cells in the mature guinea pig ear. Seven days after bilateral deafening, a 5-µl suspension of CNTF and/or BDNF adenovirus vectors was injected into the left scala tympani through the round window. Animals were sacrificed 28 days after deafening, and their inner ears were prepared for SGN counts. The SGN counts revealed that BDNF alone and the combined CNTF and BDNF treatment significantly enhanced SGN survival. CNTF did not significantly enhance the protective effect of BDNF. These data present possible strategies for enhancing SGN survival in cochlear implant procedures.
Expression and Function of Somatostatin Receptor Subtype 1 in Human Growth Hormone Secreting Pituitary Tumors Deriving from Patients Partially Responsive or Resistant to Long-Term Treatment with Somatostatin Analogs
Authors: Matrone C. , Pivonello R. , Colao A. , Cappabianca P. , Cavallo L.M. , Del Basso De Caro M.L. , Taylor J.E. , Culler M.D. , Lombardi G. , Di Renzo G.F. , Annunziato L.
Published: April 2004

The role of somatostatin (SS) receptor subtype 1 (SSTR1) in mediating the inhibitory effect of SS on growth hormone (GH) secreting pituitary tumors has been recently demonstrated. In the present study, we evaluated the effect of the selective SSTR1 agonist BIM-23745 on in vitro GH secretion in GH-secreting pituitary tumor cells, deriving from patients resistant or partially responsive to octreotide long-acting release (octreotide-LAR) or lanreotide therapy in vivo and expressing SSTR1 mRNA. In addition, the inhibiting effect of BIM-23745 on the GH secretion was compared with that of octreotide. Our data demonstrate that (1) SSTR1 receptor was present in 56.25% (9/16) of the GH-secreting adenomas examined; (2) in all GH-secreting pituitary tumors that expressed SSTR1, BIM-23745 significantly inhibited GH secretion in vitro, and (3) when SSTR1 subtype was present in tumors from patients resistant to octreotide-LAR or lanreotide therapy, BIM-23745 was able to inhibit the in vitro GH secretion. In conclusion, the results of the current study suggest that SS analogs selective for the SSTR1 may represent a further useful approach for the treatment of acromegaly in patients resistant or partially responsive to octreotide-LAR or lanreotide treatment in vivo.
Ocular Surface in Zn-Deficient Rats
Authors: Gong Huaqing , Takami Yumiko , Amemiya Tsugio , Tozu Miyako , Ohashi Yoshiharu
Published: April 2004

Purpose: We studied the cornea and conjunctiva of Zn-deficient rats with an electron microscope and time-of-flight secondary ion mass spectrometry (TOF-SIMS) to elucidate the role of trace elements in the cornea and conjunctiva. Materials and Methods: Twenty-one-day-old Wistar Kyoto rats were fed a Zn-deficient diet and deionized water for 7 weeks and then killed. The control rats were fed a Zn-deficient diet and deionized water supplemented with 3 mg Zn/100 ml. After 7 weeks on the deficient diet, another group of rats was given drinking water containing 3 mg Zn/100 ml and the usual diet containing 4.7 mg Zn/100 g for 8 weeks for recovery. The cornea and conjunctiva were examined by electron microscopy and TOF-SIMS. Results: Microvilli and microplicae in the most superficial layer of the epithelium of the Zn-deficient rat conjunctiva and cornea were prominently reduced, and dark cells were significantly increased. The numbers of goblet cells were decreased in the conjunctiva of the Zn-deficient group. Zn, Ca and Al ions were significantly fewer, but K, Fe, Cl and S ions were significantly more numerous in the Zn-deficient group than in the control group. In the cornea of the Zn-deficient group, there was significantly more Cl but less Ca and vitamin C than in the controls. Discussion: Zn deficiency may interfere with protein, nucleic acid and collagen synthesis through the reduction of Zn-containing enzymes. Myosin-like substance, actin filaments and tonofibrils are important structural components for microvilli and microplicae in the epithelium. Maldevelopment of these structural components may be related to disturbed activities of Zn-containing enzymes in protein and collagen synthesis because of Zn deficiency. In addition, Zn deficiency caused changes in the levels of Zn and other trace elements such as Ca, Al, S, Fe, and Cl and vitamin C. Conclusion: Zn deficiency resulted in poorly developed microvilli and microplicae on the ocular surface tissues, reduced the number of goblet cells and changed the quantity of trace elements and vitamin C.
Bendazac Lysine Inhibition of Human Lens Epithelial Cell Adhesion to Polymethylmethacrylate Intraocular Lenses
Authors: Soldo Lucia , Ruggieri Alessandro , Milanese Claudio , Pinza Mario , Guglielmotti Angelo
Published: April 2004

The aim of the present work was to evaluate the effect of bendazac lysine on the human lens epithelial cell line HLE-B3 adhesion to polymethylmethacrylate (PMMA) intraocular lenses (IOLs). After adherence to IOLs, cells were incubated in the presence of the drug for 24 h. The number of cells contained in a 6-mm2 area was then counted with an inverted phase microscope and adherent cells were distinguished from detached floating cells by focusing through the medium. Results obtained show that bendazac is able to induce a linear dose-dependent inhibition of HLE-B3 adhesiveness to PMMA IOLs. In particular, treatment with bendazac 33, 100 and 300 µM resulted in a 15, 32 and 54% inhibition, respectively. Statistical analysis shows that this effect is significant at 100 µM (p < 0.05) and 300 µM (p < 0.01). The analysis of the effects of bendazac on the viability and on the proliferative capacity of HLE-B3 cells did not show any drug-related toxicity up to the concentration of 400 µM. The present study demonstrates that bendazac lysine is able to inhibit adhesion of lens epithelial cells to PMMA IOLs and suggests the potential beneficial use of this drug in preventing secondary cataract development.
Influence of Insulin-Like Growth Factor-1 and Hepatocyte Growth Factor on Carotid Atherosclerosis and Cognitive Function in the Elderly
Authors: Watanabe Takuya , Yamamoto Hideki , Idei Tsunenori , Iguchi Takashi , Katagiri Takashi
Published: April 2004

Objective: This study investigated the relationship between serum levels of two neurotrophic factors, insulin-like growth factor-1 (IGF-1) and hepatocyte growth factor (HGF), and carotid atherosclerosis and cognitive function in the elderly. Methods: Serum levels of IGF-1 and HGF, carotid artery intima-media thickness (IMT), and Mini-Mental State Examination (MMSE) scores were determined in 60 subjects over 65 years old (35 patients with vascular dementia and 25 without dementia). Results: In all subjects IGF-1 levels showed a significant positive correlation with the MMSE score (r = 0.262, p = 0.0427) and a negative correlation with the IMT (r = –0.284, p = 0.0277) and the HGF level (r = –0.422, p = 0.0007). HGF levels were significantly correlated with IMT (r = 0.259, p = 0.0455) and lipoprotein(a) levels (r = 0.279, p = 0.0372). Mean MMSE scores and IGF-1 levels were significantly lower in patients with vascular dementia than in the non-demented controls. Mean IMT and the frequency of atherosclerotic plaque in the carotid arteries as well as the serum levels of HGF, LDL cholesterol, lipoprotein(a) and lipid peroxides were significantly increased in the demented patients compared with the non-demented controls. Conclusion: A decrease of IGF-1 along with an increase of HGF may reflect an underlying biological process that influences cognitive decline as well as carotid atherosclerosis in the elderly.
Ultrastructural Hippocampal and White Matter Alterations in Mild Cognitive Impairment: A Diffusion Tensor Imaging Study
Authors: Fellgiebel Andreas , Wille Paulo , Müller Matthias J. , Winterer Georg , Scheurich Armin , Vucurevic Goran , Schmidt Lutz G. , Stoeter Peter
Published: April 2004

Mild cognitive impairment (MCI) is considered to be a transitional stage between normal aging and dementia. In Alzheimer’s disease (AD), white matter structural pathology is due to Wallerian degeneration and central angiopathy. However, in MCI patients, the presence and extent of white matter alterations as a possible correlate of impaired memory function and as predictor of subsequent progression to AD is not clarified yet. Diffusion tensor imaging (DTI) reveals the ultrastructural integrity of cerebral white matter tracts. Therefore, it could detect pathological processes that modify tissue integrity in patients with MCI. In our prospective study, conventional and diffusion tensor MR scans were obtained from 14 patients with MCI, 19 patients with AD, and 10 healthy controls. Mean diffusivity (MD) and fractional anisotropy (FA) were measured in temporal, frontal, parietal and occipital white matter regions as well as in the corpus callosum (genu and splenium) and the hippocampus. MCI patients showed higher MD values in the left centrum semiovale (p = 0.013; right: p = 0.026), in the left temporal (p = 0.006), the right temporal (p = 0.014) and the left hippocampal (p = 0.002) region as compared to the control group. FA values of MCI patients and controls did not differ significantly in any region. Compared to controls, AD patients had increased MD values in the left centrum semiovale (p = 0.012), the left parietal (p = 0.001), the right parietal (p = 0.028), the left temporal (p = 0.018), the right temporal (p = 0.011) and the left hippocampal region (p = 0.002). Decreased FA values were measured in the left temporal area (p = 0.017) and in the left hippocampus (p = 0.031) in AD patients compared to controls. FA and MD values did not differ significantly between AD and MCI patients. Elevated MD values indicating brain tissue alterations in MCI patients were found in regions that are typically involved in early changes due to AD, particularly the left hippocampus. The sensitivity of distinguishing MCI patients from controls was 71.4% (with a specificity set at 80%). Therefore, the DTI technique validates the MCI concept, and diffusion tensor MR measurement can be a helpful tool to quantify MCI pathology in vivo.
Study of the Homocysteine Status in Children with Chronic Renal Failure
Authors: Farid Farida A. , Faheem Mohamed S. , Heshmat Nahla M. , Shaheen Karim Y. , Saad Sherine S.
Published: April 2004

Background/Aims: Vascular diseases are a major cause of morbidity and mortality in end-stage renal disease (ESRD) patients and they cannot be explained entirely by the prevalence of traditional risk factors for atherosclerosis. The role of hyperhomocysteinemia as an additional risk factor in the development of accelerated atherosclerosis and/or thrombosis in these patients has been suggested possibly due to homocysteine (Hcy) induced endothelial cell injury. This study was aimed at evaluation of the Hcy status in children with chronic renal failure (CRF) especially in those suffering from ESRD and the possible role of folic acid and vitamin B12 therapy in the correction of hyperhomocysteinemia if present. Methods: This study included 40 patients with CRF, 30 on regular hemodialysis (HD) treatment (group I) and 10 on conservative (medical) treatment (group II) in comparison to 20 healthy age- and sex-matched controls (group III). The basal serum levels of Hcy, folic acid and vitamin B12 as well as plasma level of activated protein C resistance (APC-R) were measured in patients and controls. Results: The mean serum Hcy was significantly higher in those on regular HD (17.9 ± 10.07 µmol/l) in comparison to those on conservative treatment (8.05 ± 2.99 µmol/l) (p < 0.001) and controls (7.07 ± 2.24 µmol/l) (p < 0.001), while there was no significant variation between the latter two groups. The mean values of APC-R, folic acid and vitamin B12 failed to show any significant difference in the three studied groups. No significant difference in the basal Hcy level between patients with previous history of vaso-occlusive disease and those without was found. Half of the patients on regular HD (group Ia) (n = 15) were given folic acid as 50 mg of 5-formyl-tetrahydrofolate (the active form of folic acid) intravenously once weekly after the dialysis session for 4 weeks. The other half (group Ib) (n = 15) received in addition to folic acid therapy, vitamin B12 1,000 µg hydroxycobalamine once intramuscularly. After therapy the mean Hcy decreased significantly in those who received folic acid and vitamin B12 (7.80 ± 3.77 µmol/l) (p < 0.001) to a level comparable to the basal levels in conservative and control groups, whereas a non-significant decrease was found in those who received folic acid only (13.3 ± 11.47 µmol/l) (p > 0.05). Conclusions: Hcy is high in children with ESRD on regular HD and combined therapy of the active form of folic acid and vitamin B12 is of value in decreasing Hcy values comparable to that in controls.
Urinary Incontinence: Sphincter Functioning from a Urological Perspective
Authors: Heesakkers John P.F.A. , Gerretsen Reza R.R.
Published: April 2004

Stress urinary incontinence (SUI) is a debilitating disorder caused by malfunctioning of the urethral sphincter. Anatomical and histological properties of the sphincter, its innervation and supporting structures are explained in relation to the closing mechanism of the bladder outlet. Urethral sphincter function is discussed from the passive concept of urethral pressure transmission to the ’hammock theory’ and the role of the pubococcygeus muscles. SUI is caused by a combination of intrinsic sphincter deficiency and urethral hypermobility. The difficult interpretation of the parameters in urodynamic investigation to assess intrinsic sphincter deficiency (ISD) and/or urethral hypermobility is discussed. Electromyography (EMG) is valuable in the assessment of the overall urethral sphincter in relation to maneuvers (kinesiological EMG) and at the level of the muscle fiber (needle EMG). The diagnostic potential of circumferential surface EMG in the urethral sphincter is reviewed in relation to the EMG features of ISD.
A Review of the Treatment Guidelines on the Management of Low Levels of High-Density Lipoprotein Cholesterol
Authors: Devroey Dirk , Vantomme Karolien , Betz Willem , Vandevoorde Jan , Kartounian Jan
Published: April 2004

This paper aims to review the guidelines on the importance given to high-density lipoprotein cholesterol (HDL-C) as a risk factor or as threshold and target level in the treatment of dyslipidemia. We developed a strategy with cholesterol-related key words to search for guidelines in the major databases. The Appraisal of Guidelines Research Evaluation (AGREE) instrument was used for the evaluation and inclusion of the guidelines. In total nine guidelines were selected. Almost all selected guidelines consider low HDL-C as a marker of an increased risk for coronary heart disease. However, only few guidelines use the level of HDL-C as a threshold or target level for the treatment of dyslipidemia. The guidelines provide only little information on the management of patients with treatment-induced low HDL-C. Instead of using total cholesterol (TC) or low-density lipoprotein cholesterol (LDL-C) we consider the use of the ratios of TC to HDL-C or LDL-C to HDL-C as a threshold as well as a target for treatment.
Acute Effect of DDD versus VVI Pacing on Arterial Distensibility
Authors: Altun Armagan , Erdogan Okan , Yildiz Mustafa
Published: April 2004

Pulse wave velocity (PWV) is a new technique and frequently used today to determine the elastic distensibility of great arteries. Increased arterial stiffness and PWV have been proposed as possible mechanisms in the initiation and/or progression and/or complications of atherosclerosis and cardiovascular disease. We evaluated the acute effect of two frequently used pacing modes (DDD vs. VVI) on arterial distensibility using PWV. Methods: Seventeen patients (age, 56 ± 14 years) implanted with DDD pacemakers were included in the study. All patients were pacemaker dependent and continuously paced at the programmed rate. PWV was measured first in DDD mode, and then the mode was switched to VVI, and PWV was measured again at the same programmed heart rate as in the DDD mode. Results: Although systolic blood pressure significantly decreased from 129 ± 18 to 119 ± 16 mm Hg (p = 0.001) after switching the mode from DDD to VVI, diastolic blood pressure (81 ± 12 vs. 80 ± 13 mm Hg; p = 0.38) did not change. In addition, PWV significantly increased from 11 ± 2.46 m/s in DDD mode to 11.29 ± 2.43 m/s (p = 0.01) after having been programmed to VVI mode. Conclusions: Our results suggest that VVI pacing increases PWV, and therefore decreases arterial distensibility, and thus may contribute to the development and progression of atherosclerosis.