bluuebunny/crossref_metadata_2025 huggingface dataset:
Evaluation of Langerhans’ cells in normal and eczematous dermatitis skin by CD1a protein immunohistochemistry: preliminary findings
Authors: Hussein Mahmoud R.
Published: February 2008

Background:  Langerhans’ cells (CD1a positive, bone marrow–derived cells), are the antigen presenting cells of the skin. Our knowledge about the status of these cells in eczematous dermatitis is incomplete.

Aim:  This study tests the hypothesis that ‘the development of eczematous dermatitis is associated with alterations of Langerhans’ cells’.

Materials and methods:  Biopsy specimens from patients with eczematous dermatitis and normal skin (20 cases, each) were studied. Langerhans’ cells were stained for CD1a using imunoperoxidase‐staining methods and mouse monoclonal antibodies.

Results:  In normal skin, CD1a+ Langerhans’ cells were seen in suprabasal position. In eczematous dermatitis skin, CD1a positive cells were seen scattered in the acanthotic epidermis. Compared with normal skin, the mean values of the Langerhans’ cells were statistically significantly higher in eczematous dermatitis [epidermal Langerhans’ cells: 1.20 (standard error of mean, SEM, 0.13) vs. 2.50 (SEM, 0.16); and dermal Langerhans’ cells: 1.30 (SEM, 0.15) vs. 2.7 (SEM, 0.15); for normal and eczematous skin, respectively; p < 0.05].

Conclusions:  The higher Langerhans’ cell counts in eczematous dermatitis suggest a possible link between antigen presenting capabilities of these cells, and development of these lesions.
Chemokine receptor expression in non‐melanoma skin cancer
Authors: Basile Jeff , Thiers Bruce , Maize John , Lathers Deanne M. R.
Published: February 2008

Background:  Previous studies suggest that chemokines and chemokine receptors have a role in the metastatic process. A correlation exists between the specific expression of these chemoattractive, pro‐inflammatory cytokines and the ability of cancer to disseminate. Prior studies have shown that in metastatic melanoma and squamous cell carcinoma of the head and neck upregulation of CXC (α) chemokine receptor (CXCR)4 and CC (β) chemokine receptor (CCR)7 expression is accompanied by downregulation of the chemokine receptor CCR6. However, the expression patterns of CCR6, CCR7 and CXCR4 in non‐melanoma skin cancer have yet to be elucidated.

Methods:  The expression patterns of CCR6, CCR7 and CXCR4 were determined using an immunohistochemical approach on formalin‐fixed, paraffin‐embedded normal, pre‐cancerous actinic (solar) keratosis, squamous cell carcinoma and basal cell carcinoma tissues.

Results:  Analysis of chemokine receptor expression showed downregulation of CCR6 and upregulation of CCR7 and CXCR4 in potentially metastatic non‐melanoma skin cancer, invasive squamous cell carcinoma, but this pattern did not exist in non‐melanoma skin cancer with no metastatic potential, basal cell carcinoma; or actinic keratosis, when compared with normal skin.

Conclusions:  Chemokine receptor expression may influence the biological behavior of non‐melanoma skin cancer. The exact mechanism by which this occurs requires further study.
Expression patterns of MITF during human cutaneous embryogenesis: evidence for bulge epithelial expression and persistence of dermal melanoblasts
Authors: Gleason Briana C. , Crum Christopher P. , Murphy George F.
Published: February 2008

Background:  The mechanisms whereby melanocytes populate the epidermis and developing hair follicles during embryogenesis are incompletely understood. Recent evidence implicates an intermediate mesenchymal stage in this evolutionary process in which HMB‐45‐positive melanocyte precursors (‘melanoblasts’) exist both in intradermal as well as intraepithelial and intrafollicular compartments. The melanocyte master transcriptional regulator, microphthalmia transcription factor (MITF), identifies mature melanocytes as well as melanocyte precursor stem cells that reside in the bulge region of the hair follicle.

Methods:  To better define the use of MITF expression in the evaluation of melanocyte ontogeny, human embryonic and fetal skin samples (n = 28) at 6–24 weeks gestation were studied immunohistochemically for expression of MITF and Mart‐1. Adjacent step sections were evaluated to correlate staining patterns with cell localization in the intraepidermal, intrafollicular and intradermal compartments.

Results:  At 6–8 weeks, MITF and Mart‐1‐positive cells were primarily intradermal with only rare positive cells in the epidermis. By 12–13 weeks, most of these cells had migrated into the epidermis, predominantly the suprabasal layers. Between 15–17 weeks, these cells localized to the basal layer and colonized developing hair follicles. Rare intradermal MITF and Mart‐1 positive cells were found as late as week 20. At 18–24 weeks, MITF and Mart‐1 positive cells were identified in the outer root sheath, bulge, and follicular bulge epithelium, in addition to the epidermis. Unexpectedly, weak but diffuse nuclear MITF expression was also present in the keratinocytes of the bulge area.

Conclusions:  The in situ migratory fate of MITF/Mart‐1‐expressing cells in fetal skin involves a well‐defined progression from intradermal to intraepidermal to intrafollicular localization. Occasional intradermal melanocytes may persist after the intraepithelial stages are completed, a finding of potential significance to melanocytic proliferations that may arise de novo within the dermis. Because MITF may play a role in stem cell maintenance, the presence of MITF in bulge epithelial cells suggests that it may be a novel marker for follicular stem cells of both epithelial and melanocytic lineage.
Acne inversa
Authors: Meixner Daniela , Schneider Sylke , Krause Markus , Sterry Wolfram
Published: February 2008

Acne inversa is a chronic inflammatory skin disease featuring cutaneous and subcutaneous nodular inflammation, fistula formation and discharge of foul‐smelling secretions. The disease can lead to functional impairment and psychological problems. There is inflammation of the terminal hair follicles in intertriginous regions, especially perianal, axillary and inguinal areas. Less often there is submammary, periumbilical, retroauricular or nuchal involvement.

Without treatment the disease is chronic and progressive. The causes of acne inversa are multifactorial and pathogenesis is still not well understood. Besides a positive family history, obesity and cigarette smoking are trigger factors. Early diagnosis and therapy of acne inversa saves the patient years of suffering.

The most effective treatment is undoubtedly the radical wide excision of the affected areas. Local measures such as radiotherapy, photodynamic therapy and cryotherapy have provided little benefit; the same is true for systemic antibiotic treatment or hormonal therapy with anti‐androgens. TNF‐alpha antagonists seem to have a promising influence on the disease. Further studies investigating the effect of these substances on acne inversa are warranted.
Cowpox infection transmitted from a domestic cat
Authors: Bonnekoh Bernd , Falk Kristof , Reckling Karl‐Friedrich , Kenklies Susanne , Nitsche Andreas , Ghebremedhin Beniam , Pokrywka Anna , Franke Ingolf , Thriene Bernd , König Wolfgang , Pauli Georg , Gollnick Harald
Published: February 2008

A 21‐year‐old immunocompetent woman developed a cowpox infec‐tion,while working as a veterinarian's assistant in a rural area.She had never received vaccinia immunization and came in contact with a fatally‐infected house cat. Under symptomatic treatment, the infection remained localized to one cheek and cleared over 3 weeks with substantial dermal‐subcutaneous tissue destruction. Orthopoxvirus detection by PCR is a modern diagnostic standard, in addition to identification by negative‐contrast electron microscopy. A promising therapeutic option is cidofovir, but this virostatic drug is not yet approved for the treatment of cowpox.
Native hyaluronic acid in dermatology – results of an expert meeting
Authors: Wiest Luitgard , Kerscher Martina
Published: February 2008

The glycosaminoglycan hyaluronic acid (HA) is a major component of the extracellular matrix of the skin and plays an important role in the metabolism of the dermis.HA is responsible for hydration,nutrient exchange and protects against free radical damage;via signaling pathways it is also involved in biologic processes like cell differentiation and motility.

Native HA has been employed for several years to help the skin to regain elasticity,turgor and moisture. In a clinical study an increase in elasticity and turgor following repeated injections with HA could be demonstrated, but this treatment approach is discussed controversially. An expert conference took place to find a consensus regarding use, aims of treatment, indications and limitations of this therapy. The decisions of the expert meeting are presented in this report.
The catalytic significance of the proposed active site residues in Plasmodium falciparum histoaspartic protease
Authors: Parr Charity L. , Tanaka Takuji , Xiao Huogen , Yada Rickey Y.
Published: February 2008

Alanine mutations of the proposed catalytically essential residues in histoaspartic protease (HAP) (H34A, S37A and D214A) were generated to investigate whether: (a) HAP is a serine protease with a catalytic triad of His34, Ser37 and Asp214 [Andreeva N, Bogdanovich P, Kashparov I, Popov M & Stengach M (2004) Proteins55, 705–710]; or (b) HAP is a novel protease with Asp214 acting as both the acid and the base during substrate catalysis with His34 providing critical stabilization [Bjelic S & Aqvist J (2004) Biochemistry43, 14521–14528]. Our results indicated that recombinant wild‐type HAP, S37A and H34A were capable of autoactivation, whereas D214A was not. The inability of D214A to autoactivate highlighted the importance of Asp214 for catalysis. H34A and S37A mutants hydrolyzed synthetic substrate indicating that neither His34 nor Ser37 was essential for substrate catalysis. Both mutants did, however, have reduced catalytic efficiency (P ≤ 0.05) compared with wild‐type HAP, which was attributed to the stabilizing role of His34 and Ser37 during catalysis. The mature forms of wild‐type HAP, H34A and S37A all exhibited high activity over a broad pH range of 5.0–8.5 with maximum activity occurring between pH 7.5 and 8.0. Inhibition studies indicated that wild‐type HAP, H34A and S37A were strongly inhibited by the serine protease inhibitor phenylmethanesulfonyl fluoride, but only weakly inhibited by pepstatin A. The data, in concert with molecular modeling, suggest a novel mode of catalysis with a single aspartic acid residue performing both the acid and base roles.
Suppression of Ischaemia‐Induced Cytokine Release by Dimaprit and Amelioration of Liver Injury in Rats
Authors: Motoki Atsuko , Adachi Naoto , Liu Keyue , Takahashi Hideo K. , Nishibori Masahiro , Yorozuya Toshihiro , Arai Tatsuru , Nagaro Takumi
Published: February 2008

Abstract: Inflammatory reactions play an important role in ischaemia/reperfusion injury in various organs. Since histamine H4action has been shown to prevent the development of ischaemia/reperfusion liver injury, we examined the effects of dimaprit, a histamine H2/H4receptor agonist, on ischaemia‐induced cytokine release and liver damage. Male Wistar rats (300 g) were subjected to warm ischaemia for 30 min. by occlusion of the left portal vein and hepatic artery under halothane anaesthesia. Saline or dimaprit (20 mg/kg, subcutaneously) was injected immediately after reperfusion of blood flow. Transient ischaemia provoked severe liver damage 24 hr after reperfusion, and the plasma concentrations of alanine transaminase and aspartate transaminase were 4600 IU/l and 13,200 IU/l, respectively. The values in the dimaprit group were 55% and 46% of those in control animals, respectively. Dimaprit also reduced the infarct size to 50%. Liver ischaemia markedly increased interleukin‐12 levels 2–24 hr after reperfusion. The dimaprit treatment depressed the values to 40–64% of those in the corresponding control group 4–24 hr after reperfusion. Since interleukin‐12 facilitates cell‐mediated cytotoxicity, the protective effect of dimaprit may be attributed to regulation of cytokine release during reperfusion.
Oxynitride Glasses
Authors: Hampshire Stuart , Pomeroy Michael J.
Published: February 2008

Oxynitride glasses are grain boundary phases within silicon nitride ceramics. The desire to understand their nature led to various investigations on oxynitride glass formation, structure, properties, and crystallization. This paper provides a review of oxynitride glasses and outlines the effect of glass chemistry, including nitrogen contents and cation ratios, on properties such as glass transition temperature, Young's modulus, and viscosity and relates this to structural features within the glass. A short outline of crystallization of oxynitride glasses to form glass–ceramics is presented.
Commutational Output Feedback Control for Disk Drive Ramp Loading
Authors: Ratliff Ryan T. , Pagilla Prabhakar R.
Published: March 2008

The feasibility of a ramp load controller using a conventional disk drive actuator is investigated. The controller eliminates the necessity of increased material requirements common in ramp load disk drives. Therefore, disk drives with lower cost, higher performance actuators can realize the linear shock protection benefits of ramp loading. A disk drive designed with a conventional actuator is outfitted with a ramp and optimized for ramp load operation. While on the ramp, there exists a set in the state space where the actuator dynamics are uncontrollable. An input commutation is required within the uncontrollable region to sustain the direction of actuator motion. Additionally, the motor torque factor, magnetic restoration bias, and friction torque are nonlinear and can be represented by functions that are Lipschitz within the actuator ramp angle. A state trajectory is generated that, when tracked, moves the actuator through the uncontrollable set for a successful load onto the disk at the desired load velocity. Because position and velocity information are not available during a load maneuver, an output feedback controller is necessary. A stable, output feedback tracking controller is designed to track the trajectory and handle the nonlinear effects. A unique disk drive is manufactured and experiments are performed to verify the complete ramp loading design strategy.
On Steering Control of Commercial Three-Axle Vehicle
Authors: Qu Qiuzhen , Zu Jean W.
Published: March 2008

The steering control laws of commercial three-axle vehicle are studied based on the closed-loop control model of the driver-vehicle-road. The steering characteristics of the three-axle vehicle can be improved through adding the steering of rear wheels. For a series of combined roads defined as standard roads where the vehicle is tested, a new proposal to optimize the design parameters of the steering system is presented. The cornering stiffness of front, middle and rear wheels and outer disturbance are considered as uncertain parameters varying over a limited range. A new controller of model-following variable structure is constructed and used for controlling front and rear wheels steering of the actual vehicle, so that the steering characteristics of the uncertain vehicle model and nonlinear vehicle model can follow the characteristics of the reference model (nominal model), namely, the vehicle can keep the same steering characteristics as the nominal model on the different roads. Simulation results have demonstrated that the proposed method is reasonable and practicable.
Graphite Whiskers in CV3 Meteorites
Authors: Fries Marc , Steele Andrew
Published: February 2008

Graphite whiskers (GWs), an allotrope of carbon that has been proposed to occur in space, have been discovered in three CV-type carbonaceous chondrites via Raman imaging and electron microscopy. The GWs are associated with high-temperature calcium-aluminum inclusion (CAI) rims and interiors, with the rim of a dark inclusion, and within an inclusion inside an unusual chondrule that bears mineralogy and texture indicative of high-temperature processing. Current understanding of CAI formation places their condensation, and that of associated GWs, relatively close to the Sun and early in the condensation sequence of protoplanetary disk materials. If this is the case, then it is a possibility that GWs are expelled from any young solar system early in its history, thus populating interstellar space with diffuse GWs. Graphite whiskers have been postulated to play a role in the near-infrared (near-IR) dimming of type Ia supernovae, as well as in the thermalization of both the cosmic IR and microwave background and in galactic center dimming between 3 and 9 micrometers. Our observations, along with the further possibility that GWs could be manufactured during supernovae, suggest that GWs may have substantial effects in observational astronomy.
Methane-Producing Microbial Community in a Coal Bed of the Illinois Basin
Authors: Strąpoć Dariusz , Picardal Flynn W. , Turich Courtney , Schaperdoth Irene , Macalady Jennifer L. , Lipp Julius S. , Lin Yu-Shih , Ertefai Tobias F. , Schubotz Florence , Hinrichs Kai-Uwe , Mastalerz Maria , Schimmelmann Arndt
Published: February 2008

A series of molecular and geochemical studies were performed to study microbial, coal bed methane formation in the eastern Illinois Basin. Results suggest that organic matter is biodegraded to simple molecules, such as H
2
and CO
2
, which fuel methanogenesis and the generation of large coal bed methane reserves. Small-subunit rRNA analysis of both the in situ microbial community and highly purified, methanogenic enrichments indicated that
Methanocorpusculum
is the dominant genus. Additionally, we characterized this methanogenic microorganism using scanning electron microscopy and distribution of intact polar cell membrane lipids. Phylogenetic studies of coal water samples helped us develop a model of methanogenic biodegradation of macromolecular coal and coal-derived oil by a complex microbial community. Based on enrichments, phylogenetic analyses, and calculated free energies at in situ subsurface conditions for relevant metabolisms (H
2
-utilizing methanogenesis, acetoclastic methanogenesis, and homoacetogenesis), H
2
-utilizing methanogenesis appears to be the dominant terminal process of biodegradation of coal organic matter at this location.
Is explosive performance influenced by androgen concentrations in young male soccer players?
Authors: Baldari C , Di Luigi L , Emerenziani G P , Gallotta M C , Sgrò P , Guidetti L
Published: February 2008

Objective:

There is growing interest in the implementation and assessment of strength and conditioning programmes among young children. The purpose of this study was to examine the association between given anthropometric characteristics, pubertal development, salivary androgen hormones and explosive leg power in young soccer players.

Methods:

51 (age range 10–14 years) soccer players were investigated. The relations between age, pubertal developmental stages, testicular volume, weight, height, body fat, fat free mass, salivary DHEAS concentrations, salivary testosterone concentrations and lower limb explosive power were evaluated.

Results:

Standing long jump length was positively correlated (p<0.05) with age (11.7 (SD 1.2) years, r = 0.66), pubertal developmental stages (mode and range: 1 (1–4), r = 0.64), testicular volume (8.8 (5.2) ml, r = 0.58), height (1.50 (0.10) m, r = 0.34), weight (43.7 (9.1) kg, r = 0.34), fat free mass (35.4 (7.2) kg, r = 0.67), salivary DHEAS concentrations (4.4 (1.2) ng/ml, r = 0.38) and negatively correlated with body fat (18.6 (7.0) kg; r = −0.49, p<0.05). There was no significant correlation between salivary testosterone concentrations (0.3 (0.1) ng/ml, r = 0.12) and standing long jump.

Conclusions:

Results of the present investigation demonstrated that age, pubertal developmental stages, testicular volume, weight, height, fat free mass, and salivary DHEAS concentrations were associated with standing long jump performance. In addition, salivary testosterone concentrations were not related to explosive leg power. Results of the present investigation suggest that the teacher/coach should evaluate long jump performance relative to the subject’s given biological characteristics, and not simply established standards based on chronological age.
Diagnostic accuracy of power Doppler ultrasound in patients with chronic tennis elbow
Authors: du Toit C , Stieler M , Saunders R , Bisset L , Vicenzino B
Published: February 2008

Objective:

To determine the diagnostic accuracy of power Doppler and grey scale ultrasonography, assess the relationship between severity measures and neovascularity, and describe the intra-tendon distribution of neovascularity in chronic tennis elbow.

Design:

Between group cross sectional study.

Setting:

Sports medicine clinic and radiology centre.

Participants:

32 affected elbows (median and range of duration: 10; 3–120 months) and 18 unaffected contralateral elbows in 25 patients (mean age 50 years) with lateral elbow pain, and 38 unaffected elbows in 19 asymptomatic participants (mean age 45 years) underwent a clinical examination (reference standard test) and grey scale and power Doppler ultrasonographic examination.

Main outcome measures:

Ultrasound examination with power Doppler identified neovascularity and grey scale ultrasound changes (lateral epicondyle bony spurring or irregularity, maximum anterior–posterior thickness, and echo characteristics) of the common extensor tendon.

Results:

Power Doppler had a strong positive likelihood ratio of 45.39, whereas a combined null finding in power Doppler and grey scale ultrasonography resulted in a robust negative likelihood ratio of 0.05. Grey scale changes were generally not as diagnostically accurate. Common extensor tendon neovascularity was equally distributed between the superficial and deep part of the tendon, and clinical severity measures did not correlate with neovascularity scores.

Conclusions:

Neovascularity identified with power Doppler ultrasonography when compared to grey scale changes (alone or in combination with Doppler) was diagnostically superior in identifying chronic tennis elbow. The lack of both neovascularity and grey scale changes on ultrasound examination also substantially increase the probability that the condition is not present and should prompt the clinician to consider other causes for lateral elbow pain.
The effects of age and skill level on knee musculature co-contraction during functional activities: A systematic review
Authors: Ford Kevin R. , van den Bogert Antonie J. , Myer Gregory D , Shapiro Robert , Hewett Timothy E.
Published: February 2008

Objectives-To systematically review the current literature relating the effects of age and skill level to motor control patterns of knee musculature co-contraction during functional movements.

Methods-A search of electronic databases was performed with the search terms specifying co-contraction (cocontract*, co-contract*, coactive* or co-activ*). The search was focused on the effects age and/or skill level and were limited by the keywords of age or skill level (skill*) or experience (experi*).

Results-The search yielded a total of six peer reviewed manuscripts that met the search criteria and were included in the review.

Conclusions-The relationship between adequate dynamic joint stability and efficient movement patterns are complex. Co-contraction related to age and skill development varies among studies due to technical and practical considerations. Adequate antagonistic co-contraction of hamstrings musculature appears to be a component of all functional movements to possibly maintain dynamic knee stability and protect against excessive joint loads. Future investigations that further delineate the appropriate lower extremity agonist and antagonist relationships during dynamic tasks may help elucidate injury risk mechanisms in specific populations.
Concurrent inspiratory muscle and cardiovascular training differentially improves both perceptions of effort and 5000 m running performance compared with cardiovascular training alone
Authors: Edwards A M , Wells C , Butterly R
Published: February 2008

Objective:

To examine whether inspiratory muscle training (IMT) is a useful additional technique with which to augment cardiovascular exercise training adaptations.

Methods:

16 healthy untrained males agreed to participate in the study and were randomly assigned to training (TRA; n = 8) and placebo (PLA; n = 8) groups. Pre- and post-training measurements of spirometry and maximal inspiratory mouth pressure (MIP) were taken in addition to i) maximal aerobic power (VO2max) and ii) 5000 m run time-trial. All subjects completed the same 4 week cardiovascular training programme which consisted of three running sessions (CV1: 5×1000 m, CV2: 3×1600 m, SP1: 20 min run) in each of the 4 weeks. IMT was performed daily by both groups using an inspiratory muscle trainer (POWERbreathe). TRA completed 30 maximal inspirations while PLA inspired 30 times against a negligible resistance.

Results:

Mean MIP increased significantly in both groups (TRA: 14.5 (SD 6.8)% change, PLA: 7.8 (7.4)% change) from pre- to post-training (p<0.01) but was not significantly related to changes in running performance. Mean CV1 training-repetition runs improved similarly in both groups, but RPE evaluations were significantly reduced in TRA (15.7 (0.7)) compared with PLA (16.6 (0.8)) at week 4 (p<0.05). Pre- to post-training changes in VO2maxwere well-matched between both TRA (+2.1 (2.3)%) and PLA (+1.3 (2.4)%) while post-intervention 5000 m performance was significantly augmented in TRA compared with PLA (TRA: 4.3 (1.6)%, PLA: 2.2 (1.9)%, p<0.05).

Conclusions:

The addition of IMT to a cardiovascular training programme augments 5000 m running performance but exerts no additional influence over VO2maxcompared with a cardiovascular-training group. This is probably due to IMT-induced reduction in perceived effort at high ventilatory rates, which is of greater consequence to longer duration time-trial performances than incremental tests of VO2max.
Is it ethical to keep interim findings of randomised controlled trials confidential?: Table 1
Authors: Miller F G , Wendler D
Published: March 2008

Data monitoring committees often are employed to review interim findings of randomised controlled trials. Interim findings are kept confidential until the data monitoring committee finds that they provide sufficiently compelling evidence regarding efficacy, typically because they have crossed the pre-defined statistical boundaries, or they raise serious concerns about safety. While this practice is vital to maintaining the scientific integrity of controlled trials and thereby ensuring their social value, it has been criticised as unethical. Commentators argue that withholding interim findings from research participants is deceptive, inconsistent with valid informed consent, and a violation of respect for participants’ autonomy. The present article examines these arguments, focusing specifically on confidential data monitoring for efficacy. This practice need not be deceptive provided its use is disclosed to prospective research participants. In addition, confidential data monitoring does not make research participants worse off than they would be in the clinical setting and represents an acceptable limitation on the options available to prospective research participants. Taken together, these considerations suggest confidential data monitoring, subject to adequate safeguards, is ethically acceptable.
Human-tissue-related inventions: ownership and intellectual property rights in international collaborative research in developing countries
Authors: Andanda P A
Published: March 2008

There are complex unresolved ethical, legal and social issues related to the use of human tissues obtained in the course of research or diagnostic procedures and retained for further use in research. The question of intellectual property rights over commercially viable products or procedures that are derived from these samples and the suitability or otherwise of participants relinquishing their rights to the samples needs urgent attention. The complexity of these matters lies in the fact that the relationship between intellectual property rights and ownership or rights pertaining to the samples on which the intellectual property right is based may either be overlooked or taken for granted. What equally makes the matter complex is that samples may be obtained from participants in developing countries and exported to developed countries for analysis and research. It is important for research ethics committees to tread carefully when reviewing research protocols that raise such issues for purposes of ensuring that appropriate benefit sharing agreements, particularly with developing countries, are in place.

This paper attempts to analyse the key questions related to ownership and intellectual property rights in commercially viable products derived from human tissue samples. Patent law is used as a point of reference as opposed to other forms of intellectual property rights such as industrial designs because it is the right that most inventors apply for in respect of human tissue-related inventions. The key questions are formulated following a systematic analysis of peer reviewed journal articles that have reported original investigations into relevant issues in this field. Most of the cases and reported studies that are referred to in this paper do not directly deal with HIV/AIDS research but the underlying principles are helpful in HIV/AIDS research as well. Pertinent questions, which members of ethics review committees should focus on in this regard are discussed and suggestions on appropriate approaches to the issues are proposed in the form of specific questions that an ethics review committee should consider. Specific recommendations regarding areas for further research and action are equally proposed.
Air pollution and mortality benefits of the London Congestion Charge: spatial and socioeconomic inequalities
Authors: Tonne C , Beevers S , Armstrong B , Kelly F , Wilkinson P
Published: February 2008

Objectives:

To alleviate traffic congestion in Central London, the Mayor introduced the Congestion Charging Scheme (CCS) in February 2003. We modelled the impact of the CCS on levels of traffic pollutants, life expectancy and socioeconomic inequalities.

Methods:

Annual average NO2and PM10were modelled using an emission-dispersion model. We assumed the meteorology and vehicle fleet remained constant during the pre- and post-CCS periods to isolate changes due to traffic flow. Air pollution concentrations were linked to small area socioeconomic, population and mortality data. Associated changes in life expectancy were predicted using life table analysis and exposure-response coefficients from the literature.

Results:

Before the introduction of the CCS, annual average NO2was 39.9 μg/m3and PM10was 26.2 μg/m3across Greater London. Concentrations were 54.7 μg/m3for NO2and 30.3 μg/m3for PM10among census wards within or adjacent to the charging zone. Absolute and relative reductions in concentrations following the introduction of the CCS were greater among charging zone wards compared to remaining wards. Predicted benefits in the charging zone wards were 183 years of life per 100 000 population compared to 18 years among the remaining wards. In London overall, 1888 years of life were gained. More deprived areas had higher air pollution concentrations; these areas also experienced greater air pollution reductions and mortality benefits compared to the least deprived areas.

Conclusions:

The CCS, a localised scheme targeting traffic congestion, appears to have modest benefit on air pollution levels and associated life expectancy. Greater reductions in air pollution in more deprived areas are likely to make a small contribution to reducing socioeconomic inequalities in air pollution impacts.
The correlative inhibition of bud and shoot growth in flax. Anatomical changes associated with the release of lateral buds from inhibition
Authors: McIntyre Gordon I. , Larmour Shirley D.
Published: March 2008

Seedlings of flax (Linum usitatissimum L.) were grown in sand culture under controlled conditions and the bud at node 3 was released from apical dominance by increasing the concentration of N in the nutrient solution. Within 24 h of increasing the N supply the number of mitoses per bud had markedly increased and within 48 h the length of the bud was significantly greater than the controls. A distinctive group of cells (the "quiescent center"), characterized by enlarged nuclei with a reduced Feulgen staining reaction, was present at the apex of all inhibited low-N buds but rapidly disappeared when the buds were released from inhibition. Of the buds examined 48 h after the N supply was increased, about 50% had no xylem in the bud trace; the rest had only a single xylem strand and none had established a connection with the stele of the parent stem. Buds examined after 72 h showed a marked increase in the number of xylem strands, but more than 75% of these buds still lacked a complete xylem connection with the vascular tissue of the parent shoot.These results support the hypothesis that the release of lateral buds from apical dominance is not dependent on the prior strengthening of the xylem connections and that associated changes in vascular tissue development are the consequence rather than the cause of the release of the bud from inhibition.
Underground design at Andekaleka Hydroelectric Development
Authors: Humphries R. W. , Jory L. T.
Published: March 2008

Andekaleka Hydroelectric Development, Republic of Malagasy (Madagascar), comprises an 8 m high intake dam, a 4 km long unlined power tunnel, a surge shaft, a concrete-lined penstock, four steel-lined branch penstocks, an underground powerhouse, and a 0.5 km long tailrace tunnel. The scheme develops a 235 m fall in the Vohitra River. Two 29 MW Francis turbines have been installed, with space left for two more identical units.This paper describes the geotechnical aspects of the underground design for the scheme. The predominant rock type is good quality granitic gneiss, which required minimal underground support and lining. Where the power tunnel 'daylights' and crosses the Sahantsiva River, steel and concrete lining and drainage tunnels have been provided.The length and design of the steel and concrete lining and the system of underground drainage are described along with the design and support for the powerhouse cavern and the support of the powerhouse crane beams on rock shoulders. Key words: tunnels, penstocks, underground powerhouse, underground drainage, underground support, tunnel lining, Madagascar.
Overview of the Canadian value-added wood products sector and the competitive factors that contribute to its success
Authors: DeLong Deborah L. , Kozak Robert A. , Cohen David H.
Published: March 2008

In recent years, there has been considerable interest in the secondary wood manufacturing sector across Canada. Strengthening and facilitating the secondary wood manufacturing or the value-added sector is seen as the next step to creating a more sustainable economy across Canada. This research considered a large sample of secondary wood manufacturers across Canada and has provided standardized information for the entire sector. To evaluate the competitive position of the Canadian secondary wood manufacturers, two steps were undertaken. First, factors that have determined success in other sectors were identified. Second, the sector’s current business environments and the factors that contribute to its success were evaluated. The data that contributed to this research was based on a mail survey that was sent to all secondary wood manufacturers across Canada. The data indicated that the majority of businesses in this sector are small to medium enterprises (SMEs) and have common concerns that effect SMEs. Problems obtaining financing for expansion, market research, expanding to new markets, and upgrading employees’ skills are examples. There are also opportunities for increasing efficiencies through lean manufacturing and optimizing supply chains, but these types of initiatives will require education and training. Using logistic regression, we found that being a member of an industry association greatly increased the likelihood of a business being profitable. Thus, industry associations could be an effective conduit for the required training and education.
Relationship between canopy disturbance history and current sapling density of Fagus grandifolia and Acer saccharum in a northern hardwood landscape
Authors: Nolet Philippe , Bouffard Daniel , Doyon Frédérik , Delagrange Sylvain
Published: March 2008

To shed light on the currently increasing proportion of Fagus grandifolia Ehrh. saplings in the tolerant hardwood forests of Quebec, we studied 48 Acer saccharum Marsh. dominated stands with contrasting histories of canopy disturbance: old commercial clear-cutting (CC), old fire (F), and either one or two partial cuts (1PC and 2PC). Our results indicated that higher densities of both F. grandifolia and A. saccharum saplings were associated with partial cutting histories (1PC and 2PC) than with severe canopy disturbance (CC and F). The density of F. grandifolia saplings was not related to any soil or stand characteristics in stands with a history of severe canopy disturbance. However, in stands with a history of partial canopy disturbances, the relative density of F. grandifolia saplings as compared with A. saccharum was related to soil C/N ratio and the presence of F. grandifolia overstory trees, whereas the absolute density showed a negative relationship with stand basal area. Therefore, it appears that partial canopy disturbances favored the regeneration of F. grandifolia relative to A. saccharum, whereas severe canopy disturbances may have provided an advantage to A. saccharum. We suggest that the presence of a light threshold can explain this shift in sapling performance between these two species.
CCL25 and CCL28 promote α4β7-integrin-dependent adhesion of lymphocytes to MAdCAM-1 under shear flow
Authors: Miles Alice , Liaskou Evaggelia , Eksteen Bertus , Lalor Patricia F. , Adams David H.
Published: February 2008

Inflammatory bowel disease is characterized by the recruitment of lymphocytes to the gut via mucosal vessels. Chemokines are believed to trigger α4β1- and α4β7-integrin-mediated adhesion to vascular cell adhesion molecule-1 (VCAM-1) and mucosal addressin cell adhesion molecule-1 (MAdCAM-1) on mucosal vessels, although the contribution of each pathway and the chemokines involved are not well characterized. These interactions occur under conditions of hemodynamic shear, which is critical in determining how lymphocytes integrate chemokine signals to promote transmigration. To define the role of specific chemokines in mediating lymphocyte adhesion to VCAM-1 and MAdCAM-1, we studied the ability of immobilized chemokines to activate adhesion of human lymphocytes in a flow-based adhesion assay. Adhesion to immobilized MAdCAM-1 was α4β7dependent, with no contribution from α4β1, whereas α4β1mediated rolling and static adhesion on VCAM-1. Immobilized CC-chemokine ligand (CCL) 25 and CCL28 were both able to trigger α4β7-dependent lymphocyte arrest on MAdCAM-1 under shear, highlighting a potential role for these chemokines in the arrest of lymphocytes on postcapillary venules in the gut. Neither had any effect on adhesion to VCAM-1, suggesting that they selectively trigger α4β7-mediated adhesion. Immobilized CCL21, CCL25, CCL28, and CXC-chemokine ligand (CXCL) 12 all converted rolling adhesion to static arrest on MAdCAM-1 by activating lymphocyte integrins, but only CCL21 and CXCL12 also triggered a motile phenotype characterized by lamelipodia and uropod formation. Thus α4β1/VCAM-1 and α4β7/MAdCAM-1 operate independently to support lymphocyte adhesion from flow, and chemokines may act in concert with one chemokine triggering integrin-mediated arrest and a second chemokine promoting motility and transendothelial migration.
The tripeptide analog feG ameliorates severity of acute pancreatitis in a caerulein mouse model
Authors: Rifai Yusnita , Elder Alison S. F. , Carati Colin J. , Hussey Damian J. , Li Xin , Woods Charmaine M. , Schloithe Ann C. , Thomas Anthony C. , Mathison Ronald D. , Davison Joseph S. , Toouli James , Saccone Gino T. P.
Published: February 2008

Acute pancreatitis (AP) is associated with significant morbidity and mortality; however, there is no specific treatment for this disease. A novel salivary tripeptide analog, feG, reduces inflammation in several different animal models of inflammation. The aims of this study were to determine whether feG reduced the severity of AP and modifies the expression of pancreatic ICAM-1 mRNA during AP in a mouse model. AP was induced in mice by hourly (×12) intraperitoneal injections of caerulein. A single dose of feG (100 μg/kg) was coadministered with caerulein either at time 0 h (prophylactic) or 3 h after AP induction (therapeutic). Plasma amylase and pancreatic MPO activities and pancreatic ICAM-1 mRNA expression (by RT-PCR) were measured. Pancreatic sections were histologically assessed for abnormal acinar cells and interstitial space. AP induction produced a sevenfold increase in plasma amylase, a tenfold increase in pancreatic MPO activity, and a threefold increase in interstitial space, and 90% of the acinar cells were abnormal. Prophylactic treatment with feG reduced the AP-induced plasma amylase activity by 45%, pancreatic MPO by 80%, the proportion of abnormal acinar cells by 30%, and interstitial space by 40%. Therapeutic treatment with feG significantly reduced the AP-induced abnormal acinar cells by 10% and the interstitial space by 20%. Pancreatic ICAM-1 mRNA expression was upregulated in AP and was reduced by 50% with prophylactic and therapeutic treatment with feG. We conclude that feG ameliorates experimental AP acting at least in part by modulating ICAM-1 expression in the pancreas.
Resveratrol inhibits high glucose-induced PI3K/Akt/ERK-dependent interleukin-17 expression in primary mouse cardiac fibroblasts
Authors: Venkatachalam Kaliyamurthi , Mummidi Srinivas , Cortez Dolores M. , Prabhu Sumanth D. , Valente Anthony J. , Chandrasekar Bysani
Published: February 2008

We investigated the expression of the proinflammatory cytokine interleukin (IL)-17 in cardiac fibroblasts and its induction by high glucose (HG). Our results show that primary mouse cardiac fibroblasts (mCFs) secrete low basal levels of IL-17 and that HG (25 mM d-glucose) as opposed to low glucose (5 mM d-glucose + 20 mM mannitol) significantly enhances its secretion. HG induces IL-17 mRNA expression by both transcriptional and posttranscriptional mechanisms. HG induces phosphoinositide 3- kinase [PI3K; inhibited by adenoviral (Ad).dominant negative (dn)PI3Kp85], Akt (inhibited by Ad.dnAkt1), and ERK (inhibited by PD-98059) activation and induces IL-17 expression via PI3K→Akt→ERK-dependent signaling. Moreover, mCFs express both IL-17 receptors A and C, and although IL-17RA is upregulated, HG fails to modulate IL-17RC expression. Furthermore, IL-17 stimulates net collagen production by mCFs. Pretreatment with the phytoalexin resveratrol blocks HG-induced PI3K-, Akt-, and ERK-dependent IL-17 expression. These results demonstrate that 1) cardiac fibroblasts express IL-17 and its receptors; 2) HG upregulates IL-17 and IL-17RA, suggesting a positive amplification loop in IL-17 signaling in hyperglycemia; 3) IL-17 enhances net collagen production; and 4) resveratrol can inhibit these HG-induced changes. Thus, in hyperglycemic conditions, IL-17 may potentiate myocardial inflammation, injury, and remodeling through autocrine and paracrine mechanisms, and resveratrol has therapeutic potential in ameliorating this effect.
Breathing through an inspiratory threshold device improves stroke volume during central hypovolemia in humans
Authors: Ryan Kathy L. , Cooke William H. , Rickards Caroline A. , Lurie Keith G. , Convertino Victor A.
Published: February 2008

Inspiratory resistance induced by breathing through an impedance threshold device (ITD) reduces intrathoracic pressure and increases stroke volume (SV) in supine normovolemic humans. We hypothesized that breathing through an ITD would also be associated with a protection of SV and a subsequent increase in the tolerance to progressive central hypovolemia. Eight volunteers (5 men, 3 women) were instrumented to record ECG and beat-by-beat arterial pressure and SV (Finometer). Tolerance to progressive lower body negative pressure (LBNP) was assessed while subjects breathed against either 0 (sham ITD) or −7 cmH2O inspiratory resistance (active ITD); experiments were performed on separate days. Because the active ITD increased LBNP tolerance time from 2,014 ± 106 to 2,259 ± 138 s ( P = 0.006), data were analyzed (time and frequency domains) under both conditions at the time at which cardiovascular collapse occurred during the sham experiment to determine the mechanisms underlying this protective effect. At this time point, arterial blood pressure, SV, and cardiac output were higher ( P ≤ 0.005) when breathing on the active ITD rather than the sham ITD, whereas indirect indicators of autonomic activity (low- and high-frequency oscillations of the R-to-R interval) were not altered. ITD breathing did not alter the transfer function between systolic arterial pressure and R-to-R interval, indicating that integrated baroreflex sensitivity was similar between the two conditions. These data show that breathing against inspiratory resistance increases tolerance to progressive central hypovolemia by better maintaining SV, cardiac output, and arterial blood pressures via primarily mechanical rather than neural mechanisms.
Spontaneous action potential generation due to persistent sodium channel currents in simulated carotid body afferent fibers
Authors: Donnelly David F.
Published: February 2008

The mechanism by which action potentials (APs) are generated in afferent nerve fibers in the carotid body is unknown, but it is generally speculated to be release of an excitatory transmitter and synaptic depolarizing events. However, previous results suggested that Na+channels in the afferent nerve fibers play an important role in this process. To better understand the potential mechanism by which Na+channels may generate APs, a mathematical model of chemoreceptor nerve fibers that incorporated Hodgkin-Huxley-type Na+channels with kinetics of activation and inactivation, as determined previously from recordings of petrosal chemoreceptor neurons, was constructed. While the density of Na+channels was kept constant, spontaneous APs arose in nerve terminals as the axonal diameter was reduced to that in rat carotid body. AP excitability and pattern were similar to those observed in chemoreceptor recordings: 1) a random pattern at low- and high-frequency discharge rates, 2) a high sensitivity to reductions in extracellular Na+concentration, and 3) a variation in excitability that increased with AP generation rate. Taken together, the results suggest that an endogenous process in chemoreceptor nerve terminals may underlie AP generation, a process independent of synaptic depolarizing events.