bluuebunny/crossref_metadata_2025 huggingface dataset:
Trigger Points in the Suboccipital Muscles and Forward Head Posture in Tension‐Type Headache
Authors: Fernández‐de‐las‐Peñas César , Alonso‐Blanco Cristina , Cuadrado Maria Luz , Gerwin Robert D. , Pareja Juan A.
Published: January 2006

Objective.—To assess the presence of trigger points (TrPs) in the suboccipital muscles and forward head posture (FHP) in subjects with chronic tension‐type headache (CTTH) and in healthy subjects, and to evaluate the relationship of TrPs and FHP with headache intensity, duration, and frequency.

Background.—Tension‐type headache (TTH) is a prototypical headache in which myofascial TrPs in the cervical and pericranial musculature can play an important role.

Design.—A blinded, controlled pilot study.

Methods.—Twenty CTTH subjects and 20 matched controls without headache participated. TrPs were identified by eliciting referred pain with palpation, and increased referred pain with muscle contraction. Side‐view pictures of each subject were taken in sitting and standing positions, in order to assess FHP by measuring the craniovertebral angle. Both measures were taken by a blinded assessor. A headache diary was kept for 4 weeks in order to assess headache intensity, frequency, and duration.

Results.—Sixty‐five percent (13/20) CTTH subjects showed active TrPs and 35% (7/20) had latent TrPs in the suboccipital muscles. Six (30%) controls also had latent TrPs. Differences in the presence of suboccipital muscle TrPs between both the groups were significant for active TrPs (P < .001) but not for latent TrPs (P > .5). CTTH subjects with active TrPs reported a greater headache intensity and frequency than those with latent TrPs (P < .05). The degree of FHP was greater in CTTH subjects than in controls in both sitting and standing positions (P < .01). Within the CTTH group, there was a negative correlation between the craniovertebral angle and the frequency of headache (rs=−0.6, P < .01, in sitting position; rs=−0.5, P < .05, in standing position). CTTH subjects with active TrPs had a greater FHP than those with latent TrPs, though this difference was not significant.

Conclusions.—Suboccipital active TrPs and FHP were associated with CTTH. CCTH subjects with active TrPs reported a greater headache intensity and frequency than those with latent TrPs. The degree of FHP correlated positively with headache duration, headache frequency, and the presence of suboccipital active TrPs.
Migraines Linked to Intrapulmonary Right‐to‐Left Shunt
Authors: Thenganatt John , Schneiderman Jacob , Hyland Robert H. , Edmeads John , Mandzia Jennifer L. , Faughnan Marie E.
Published: January 2006

Objective.—To determine if there is an association between migraines and intrapulmonary right‐to‐left shunt.

Background.—Several studies have described an association between migraines and intracardiac right‐to‐left shunt.

Methods.—Patients with hereditary hemorrhagic telangiectasia (HHT) were retrospectively recruited from the Toronto Hereditary Hemorrhagic Telangiectasia Center Clinical Database. All patients had been prospectively, systematically asked about a history of migraines and systematically screened for pulmonary and cerebral arteriovenous malformations (AVMs). All patients with a definite diagnosis of HHT, assessed during a 2‐year period (February 1997 to April 1999), were included. Univariate analyses and logistic regression were performed, for migraine as the dependent variable and the following independent variables: age, sex, pulmonary AVMs, and cerebral AVMs.

Results.—Of the 200 patients assessed during the 2‐year period, 124 (62%) had a definite diagnosis of HHT and were included in the analysis. Eighty (65%) were females. Forty‐seven (38%) of the HHT patients had a history of migraine, of whom 38 (81%) had migraine with aura. The prevalence of migraine was greater in patients with pulmonary AVMs (46%) compared to patients without pulmonary AVMs (33%), OR = 1.7 (0.8 to 3.6), though this did not reach statistical significance (P= .14). Pulmonary AVMs were significantly associated with migraine (OR = 2.4, 95% CI = 1.1 to 5.5, P= .04), after adjustment for age and sex, using logistic regression.

Conclusions.—There is a significant association between intrapulmonary right‐to‐left shunt and migraine.
Could Statins Be Useful in the Treatment of Patients With Migraine?
Authors: Liberopoulos Evagelos N. , Mikhailidis Dimitris P.
Published: January 2006

Migraine is a common and disabling neurological disorder. Studies have shown that patients with migraine (especially those with typical aura with migraine) have an unfavorable cardiovascular risk profile and an increased risk of early‐onset (<45 years) ischemic stroke. Statins are effective hypolipidemic drugs that reduce cardiovascular‐related morbidity and death in patients with or without established atherosclerotic vascular disease.

We report a patient whose frequent attacks of typical aura with migraine completely resolved after the initiation of treatment with a statin. In this context, we comment on the possible effects of statins on the pathophysiology of migraine.

We suggest that statins may be useful drugs in the treatment of migraine because they could reduce the increased cardiovascular risk in these patients and also attenuate migraine attacks. Only a randomized prospective study in this population could provide a definite answer to these speculations.
Patterns of Genetic Variation in the Hypertension Candidate Gene GRK4: Ethnic Variation and Haplotype Structure
Authors: Lohmueller K. E. , Wong L. J. C. , Mauney M. M. , Jiang L. , Felder R. A. , Jose P. A. , Williams S. M.
Published: January 2006

Association studies using single nucleotide polymorphisms (SNPs) have the potential to help unravel the genetic basis of hypertension. Nevertheless, to date, association studies of hypertension have yielded ambiguous results. It is becoming clear that such association studies must be interpreted within the context of the genetic structure of the populations being studied, and patterns of variation within specific genomic regions. With this in mind we analyzed genetic variation in the G protein‐coupled receptor kinase 4 (GRK4) gene, a gene whose product has recently been shown to inhibit the dopamine receptor D1 (DRD1) from increasing sodium excretion. We genotyped three previously identified GRK4 SNPs, as well as ten additional SNPs, over 71.6 kb of the GRK4 locus in four populations: African Americans, Asians, Hispanics and Caucasians. Haplotype structure varied among populations, with Hispanics and Caucasians having the most linkage disequilibrium (LD) among SNPs. African Americans had three shorter haplotype blocks, while patterns of markers in the Asian populations demonstrated less LD among markers, a pattern inconsistent with block structure. We observed limited haplotype diversity in each of the four populations, with differing haplotype frequencies among the ethnic groups. We also found substantial evidence for population differentiation, with the largest differences between the African‐American and Asian samples with FST values in the upper 90th percentile when compared to a genome‐wide distribution. However, for all population comparisons, FST values decreased sharply in the 3′ region of the gene. This pattern of differentiation among populations is consistent with selection in this part of the gene maintaining similar patterns of variation among otherwise divergent populations. Our results document not only different allele frequencies between populations, but differences in haplotype structure that may be important in evaluating association studies between hypertension and GRK4.
Point Mutation of an EYA1‐gene Splice Site in a Patient with Oto‐facio‐cervical Syndrome
Authors: Estefanía E. , Ramírez‐Camacho R. , Gomar M. , Trinidad A. , Arellano B. , García‐Berrocal J. R. , Verdaguer J. M. , Vilches C.
Published: January 2006

Mutations of the EYA1 gene (8q13.3) are the most common known cause of the branchio‐oto‐renal dysplasia (BOR), an autosomal dominant disease that includes developmental defects of branchial arch structures, middle and/or inner ear and kidney. The distinction between BOR and other dysplasias, such as oto‐facio‐cervical syndrome (OFC), is challenged by frequent association of the former to other diverse malformations, and by variable expressivity even within the same family. OFC is characterized by trophic alterations of the facies and shoulder girdle in addition to the malformations seen in BOR. Recent characterization of one OFC patient shed some light on the controversy over whether OFC and BOR are the same disease, and led to the hypothesis that OFC is caused by contiguous deletions of EYA1 and adjacent genes. By contrast, we show here that an OFC patient bears a single‐nucleotide substitution in a splice site of EYA1. Our results indicate that not only major rearrangements, but also point mutations altering the EYA1 reading frame, can be found in patients with OFC syndrome.
In vivo recovery and survival of apheresis and whole blood‐derived platelets: a paired comparison in healthy volunteers
Authors: Arnold Donald M. , Heddle Nancy M. , Kulczycky Myron , Carruthers Julie , Sigouin Christopher , Blajchman Morris A.
Published: January 2006

BACKGROUND: Methods of platelet preparation may alter the recovery and survival characteristics of platelets following transfusion. As suggested by a recent clinical trial, platelet recovery may be better preserved with apheresis platelet preparations than with platelets prepared from whole blood by the platelet‐rich plasma (PRP) method.

STUDY DESIGN AND METHODS: In vivo platelet recovery and survival of autologous leukoreduced (LR) apheresis platelets and autologous filter‐LR PRP platelets were compared in 22 healthy volunteers using a paired crossover design. On the same day, each participant gave one apheresis platelet donation and one whole blood donation from which platelets were recovered from the PRP. The sequence of donations was randomly assigned for each participant. Following 5 days of storage and bacterial screening, a sample from each platelet product was labeled with either 51chromium or 111indium (randomly assigned) and both samples were simultaneously re‐infused into the original donor. Recovery and γ‐function platelet survival were calculated for each platelet product using the multiple hit mathematical model.

RESULTS: Five day stored LR‐apheresis platelets had 18.8 percent better recovery, and 32.9 percent longer γ‐survival than filter‐LR PRP platelets. Stored apheresis platelets had lower p‐selectin expression and higher morphology scores than stored PRP platelets.

CONCLUSIONS: Filter‐LR PRP platelet preparation appears to adversely affect platelet recovery and survival characteristics. The reasons for this effect are not clear. These results may not apply to all apheresis and PRP methods of platelet preparation.
Demographic characteristics and risks for transfusion‐transmissible infection among blood donors in Xinjiang autonomous region, People's Republic of China
Authors: Zaller Nickolas , Nelson Kenrad E. , Ness Paul , Wen Guoxing , Kewir Turgun , Bai Xuhua , Shan Hua
Published: January 2006

BACKGROUND: The recruitment and retention of voluntary, nonremunerated blood donors continues to be a challenge in China. Understanding donor demographics and donor characteristics is crucial for any blood center in developing strategies to recruit potential donors.

STUDY DESIGN and METHODS: The study population included all 29,784 whole blood donors from January 1 to December 31, 2003, at the Urumqi City Blood Center or one of its mobile blood collection buses. Demographic data, location, and frequency of donation and results of testing for transfusion‐transmissible infection (TTI) were evaluated.

RESULTS: The typical blood donor in Urumqi is male, less than 36 years of age, and Han Chinese; has at least a high school education; is a first‐time donor; and donated at a mobile blood collection bus. The majority, 71 percent, were first‐time donors. Among all donors, the seropreva‐lence rate of TTI was 3.5 percent for first‐time donors, 2.7 percent for donors who donated twice, and 2.1 percent for donors who had donated three or more times. Han Chinese had lower seroprevalence rates of TTIs than ethnic minorities. Lower seroprevalence rates of TTIs were found among donors at mobile buses than at the blood centers.

CONCLUSION: Similar to other donor populations, higher rates of TTIs were observed among first‐time donors, and the prevalence decreased among repeated donors. One possible strategy for improving the safety of the blood supply might be for the blood center to recruit a cadre of donors who donate repeatedly, instead of relying on campaigns to recruit new donors from workplaces at each donation cycle.
Transfusion of 7‐day‐old amotosalen photochemically treated buffy‐coat platelets to patients with thrombocytopenia: a pilot study
Authors: Simonsen Anne C. , Johansson Pär I. , Conlan Maureen G. , Jacquet Michele , Lin Jin‐Sying , Junge Klaus , Lin Lily , Sørensen Henning , Borregaard Niels , Flament Jocelyne
Published: January 2006

BACKGROUND:  Photochemical treatment (PCT) of platelets (PLTs) with amotosalen and ultraviolet A light to inactivate bacteria may facilitate extension of storage from 5 to 7 days.

STUDY DESIGN AND METHODS:  A randomized, double‐blinded, crossover, noninferiority, single‐site pilot study utilizing pooled buffy‐coat PLTs was conducted. The primary endpoint was the 1‐hour corrected count increment (CCI) after one transfusion each of 7‐day‐old PCT and reference (R) PLT components. Secondary endpoints included 1‐hour count increment, time to next transfusion, hemostasis, transfusion reactions, and serious adverse events.

RESULTS:  Twenty patients with thrombocytopenia were randomly assigned: 9 to the PCT‐R sequence and 11 to the R‐PCT sequence. A significant treatment‐by‐period interaction was observed. Therefore, the first period only was also analyzed for the primary endpoint. Including both treatment periods, mean 1‐hour CCI was 6587 ± 4531 for PCT versus 8935 ± 5478 for R‐PLTs. For the first period only, mean 1‐hour CCI was 8739 ± 3785 for PCT versus 7433 ± 5408 for R‐PLTs. The upper bound of the one‐sided 95 percent confidence interval of 2400 for the mean difference was higher than the specified noninferiority margin of 2200 for both analyses. Overall median time to next transfusion was 22 hours for PCT versus 27 hours for R‐PLTs. Hemostasis was adequate and no transfusion reactions or serious adverse events were reported.

CONCLUSIONS:  Although this pilot study of a limited number of patients failed to show noninferiority within the specified noninferiority margin, 7‐day‐old PCT PLTs showed acceptable efficacy and safety for support of thrombocytopenia. The results, however, warrant evaluation in a larger trial of 7‐day‐old PCT PLTs.
Predictive ability of sequential surveys in determining donor loss from increasingly stringent variant Creutzfeldt‐Jakob disease deferral policies
Authors: O'Brien Sheila F. , Chiavetta Jo Anne , Goldman Mindy , Fan Wenli , Nair Rama C. , Sher Graham D. , Vamvakas Eleftherios C.
Published: January 2006

BACKGROUND:  Predonation screening questions about travel increase the safety of the blood supply from diseases such as variant Creutzfeldt‐Jakob disease (vCJD) and malaria. This study examines the ability of sequential surveys to predict actual travel deferrals and the operational validity of travel questions.

STUDY DESIGN AND METHODS:  To assess donor travel histories before implementing key deferral policies, two donor surveys were carried out at Canadian Blood Services collection sites in February 1999 (8026 donors) and March 2001 (13,623 donors). In‐person interviews were carried out with 1530 donors to assess the operational validity of the short travel question. Time‐series analysis was used to determine whether there was a change in deferrals when deferral policies were implemented. Predicted donor loss estimates based on survey results were compared with actual deferrals.

RESULTS:  Deferrals increased significantly (p < 0.05) when vCJD deferral policies were implemented in October 1999 and September 2001, but not in October 2000. Survey data accurately predicted deferrals 6 months after implementation from the initial policy (2.51% predicted vs. 2.51% actual), but there were fewer deferrals than predicted for the second (2.89% predicted vs. 2.26% actual, p < 0.01) and third deferral policies (3.10% predicted vs. 1.89% actual, p < 0.01). There was 96 percent agreement between donor responses to a short screening question and a detailed travel history.

CONCLUSION:  The initial survey accurately predicted the actual donor deferral rate, but the deferral rate was less than predicted for subsequent, more stringent donor deferral policies. Donors answered a short travel question suitable for donor screening similarly to a very detailed travel history.
Effects of skin disinfection method, deviation bag, and bacterial screening on clinical safety of platelet transfusions in the Netherlands
Authors: De Korte Dirk , Curvers Joyce , De Kort Wim L.A.M. , Hoekstra Tiny , Van Der Poel Cees L. , Beckers Erik A.M. , Marcelis Jan H.
Published: January 2006

BACKGROUND:  Bacterial contamination of blood products is a great hazard for development of fatal transfusion reactions. Bacterial screening of platelet concentrates (PC) by aerobic and anaerobic culturing (BacT/ALERT, bioMérieux) was introduced in the Netherlands in October 2001.

STUDY DESIGN AND METHODS:  In November 2002, a nationwide, uniform skin cleansing method was introduced with a double‐swab disinfection with 70 percent isopropyl alcohol. One location routinely used an integrated diversion bag to collect the first 20 to 30 mL.

RESULTS:  Over the calendar years 2002 and 2003, in total 113,093 PCs derived from pooled buffy coats were screened. After introduction of the new disinfection method, 0.85 percent were initially positive. This was a small reduction compared to the previous disinfection methods under which 0.95 percent were initially positive. The location with use of the diversion bag showed a significantly lower frequency of bacterial contamination, with 0.50 percent before and 0.37 percent after introduction of 70 percent isopropyl alcohol. In addition 8000 apheresis PCs were also screened, showing 24 initially positive samples (0.30%).

CONCLUSION:  The use of the diversion bag and, to a lesser extent, the use of double swabs with 70 percent isopropyl alcohol, led to a reduction of contamination. As expected, predominant contamination with resident skin bacteria was reduced. The combination of diversion bag and new disinfection led to a frequency of initial positive results for pooled five‐donor PCs, which is similar to that of single‐donor apheresis PCs. Furthermore, the bacterial detection system and associated product recall procedures have been shown to be effective in preventing transfusion of contaminated PCs and/or related red cells, especially for rapidly growing bacteria.
Composition and clinical use of hemodialysates
Authors: SAM Ramin , VASEEMUDDIN Mohammad , LEONG Wai Hong , ROGERS Brooks E. , KJELLSTRAND Carl M. , ING Todd S.
Published: January 2006

A thorough knowledge and understanding of the principles underlying the preparation and the clinical application of hemodialysates can help us provide exemplary patient care to individuals having end‐stage renal disease. It is prudent to be conversant with the following: (a) how each ingredient in a dialysate works, (b) the clinical circumstances under which the concentration of an ingredient can be altered, and (c) the special situations in which unconventional ingredients can be introduced into a dialysate. The potential to enrich dialysates with appropriate ingredients (such as iron compounds) is limited only by the boundaries of our imagination.
Survival to discharge among patients treated with continuous renal replacement therapy
Authors: WALD Ron , DESHPANDE Rushi , BELL Chaim M. , BARGMAN Joanne M.
Published: January 2006

Continuous renal replacement therapy (CRRT) is widely used in critically ill patients with acute renal failure (ARF). The survival of patients who require CRRT and the factors predicting their outcomes are not well defined. We sought to identify clinical features to predict survival in patients treated with CRRT. We reviewed the charts of all patients who received CRRT at the Toronto General Hospital during the year 2002. Our cohort (n=85) represented 97% of patients treated with this modality in 3 critical care units. We identified demographic variables, underlying diagnoses, transplantation status, location (medical‐surgical, coronary, or cardiovascular surgery intensive care units), CRRT duration, baseline estimated glomerular filtration rate (eGFR), and presence of oliguria (<400 mL/day) on the day of CRRT initiation. The principal outcome was survival to hospital discharge. Among those alive at discharge, we assessed whether there was an ongoing need for renal replacement therapy. Greater than one‐third (38%, 32/85) of patients survived to hospital discharge. Three (9%) survivors remained dialysis‐dependent at the time of discharge. Survivors were younger than nonsurvivors (mean age 56 vs. 60 years), were on CRRT for a shorter duration (7 vs. 13 days), and had a higher baseline eGFR (74 vs. 62 mL/min/m2). Patient survival varied among different critical care units (medical surgical 33%, coronary 38%, and cardiovascular surgery 45%). Multivariable logistic regression revealed that shorter duration of CRRT, nonoliguria, and baseline eGFR >60 mL/min/m2 were independently associated with survival to hospital discharge (p<0.05). Critically ill patients with ARF who require CRRT continue to have high in‐hospital mortality. A shorter period of CRRT dependence, nonoliguria and higher baseline renal function may predict a more favorable prognosis. The majority of CRRT patients who survive their critical illness are independent of dialysis at the time of hospital discharge.
Disturbances of antimicrobial lipids in atopic dermatitis
Authors: Melnik Bodo
Published: January 2006

Patients with atopic dermatitis exhibit an increased susceptibility to cutaneous infections, especially to pathological colonization with superantigen‐secreting Staphylococcus aureus. Recent attention has been focused on antimicrobial peptides, especially on cathelicidin and human β‐defensin‐2, which are under‐expressed in atopic skin. Antimicrobial lipids from the stratum corneum are also major contributors to cutaneous antimicrobial defense. Current aspects of biochemistry and function of antimicrobial lipids in atopic dermatitis are reviewed in detail. The major classes of stratum corneum lipids with antimicrobial activity are free fatty acids, glucosylceramides, and free sphingosines. Diminished levels of free sphingosines in the stratum corneum have recently been detected in atopic dermatitis and have been associated with the pathological colonization of atopic skin with Staphylococcus aureus. The superantigen staphylococcal enterotoxin B has been shown to reduce the suppressive effect of regulatory T cells on T‐cell proliferation, thus augmenting T‐cell activation in patients with atopic dermatitis. The killing of superantigen‐secreting bacterial strains with topically applied antimicrobial lipids offers new antiseptic and immunomodulatory options for the treatment and secondary prevention of atopic dermatitis.
New therapeutic approaches for solid tumors: Histone deacetylase, methyltransferase and proteasome inhibitors
Authors: Becker Jürgen C. , Ugurel Selma , Bröcker Eva‐Bettina , Schrama David , Houben Roland
Published: January 2006

Recent results from basic and translational research on tumor genesis and progression establish the basis for future therapeutic approaches. Targeted therapeutics are tailored toward the molecular abnormalities that cause tumor progression and could potentially provide an effective, non‐toxic therapeutic approach in a broad range of cancers including melanoma. Cancer is as much a (cyto)genetic disease as it is an epigenetic disease. Indeed, the fate of the cell depends on a delicate balance between expression and repression of genes. The notion that drastic changes in DNA methylation and histone modifications are present in a variety of human tumors has prompted the development and characterization of epigenetic drugs. Inhibitors of histone deacetylases and methyltransferases as well as of the proteasome are covered in this review.
VEGF gene expression is regulated post‐transcriptionally in macrophages
Authors: Du Min , Roy Kristen M. , Zhong Lihui , Shen Zheng , Meyers Hannah E. , Nichols Ralph C.
Published: January 2006

The macrophage is critical to the innate immune response and contributes to human diseases, including inflammatory arthritis and plaque formation in atherosclerosis. Vascular endothelial growth factor (VEGF) is an angiogenic cytokine that is produced by macrophages. To study the regulation of VEGF production in macrophages we show that stimulation of monocyte‐macrophage‐like RAW‐264.7 cells by lipopolysaccharide (LPS) increases expression of VEGF mRNA and protein. Three alternative splicing VEGF mRNA isoforms are produced, and the stability of VEGF mRNA increases following cellular activation. To study post‐transcriptional regulation of the VEGF gene the 3′‐untranslated region (3′ UTR) was introduced into the 3′ UTR of the luciferase gene in a reporter construct. In both RAW‐264.7 cells and thioglycollate‐elicited macrophages, the 3′ UTR sequence dramatically reduces reporter expression. Treatment with activators of macrophages, including LPS, lipoteichoic acid, and VEGF protein, stimulates expression of 3′ UTR reporters. Finally, mapping studies of the 3′ UTR of VEGF mRNA show that deletion of the heterogeneous nuclear ribonucleoprotein l binding site affects basal reporter expression in RAW‐264.7 cells, but does not affect reporter activation with LPS. Together these results demonstrate that a post‐transcriptional mechanism contributes to VEGF gene expression in activated macrophage cells.
Cell type‐specific transgene expression of the prion protein in Xenopus intermediate pituitary cells
Authors: van Rosmalen Jos W. G. , Martens Gerard J. M.
Published: January 2006

The cellular form of prion protein (PrPC) is anchored to the plasma membrane of the cell and expressed in most tissues, but predominantly in the brain, including in the pituitary gland. Thus far, the biosynthesis of PrPC has been studied only in cultured (transfected) tumour cell lines and not in primary cells. Here, we investigated the intracellular fate of PrPCin vivo by using the neuroendocrine intermediate pituitary melanotrope cells of the South‐African claw‐toed frog Xenopus laevis as a model system. These cells are involved in background adaptation of the animal and produce high levels of its major secretory cargo proopiomelanocortin (POMC) when the animal is black‐adapted. The technique of stable Xenopus transgenesis in combination with the POMC gene promoter was used as a tool to express Xenopus PrPC amino‐terminally tagged with the green fluorescent protein (GFP–PrPC) specifically in the melanotrope cells. The GFP–PrPC fusion protein was expressed from stage‐25 tadpoles onwards to juvenile frogs, the expression was induced on a black background and the fusion protein was subcellularly located mainly in the Golgi apparatus and at the plasma membrane. Pulse–chase metabolic cell labelling studies revealed that GFP–PrPC was initially synthesized as a 45‐kDa protein that was subsequently stepwise glycosylated to 48‐, 51‐, and eventually 55‐kDa forms. Furthermore, we revealed that the mature 55‐kDa GFP–PrPC protein was sulfated, anchored to the plasma membrane and cleaved to a 33‐kDa product. Despite the high levels of transgene expression, the subcellular structures as well as POMC synthesis and processing, and the secretion of POMC‐derived products remained unaffected in the transgenic melanotrope cells. Hence, we studied PrPC in a neuroendocrine cell and in a well‐defined physiological context.
An investigation into the physiological relevance of the vagal tachycardia in the anaesthetized dog
Authors: Markos F. , Snow H. M.
Published: January 2006

Aim:  Our aim was primarily to assess whether or not a vagal tachycardia can be elicited in vivo without administration of atropine, and secondly to evaluate whether the dose of atropine, a muscarinic antagonist, determines the magnitude of the tachycardia.

Methods:  Experiments were carried out in the presence of atenolol (2 mg kg−1). The vagal tachycardia requires high vagal activity which was induced by noradrenaline infusion (20 μg min−1). Two techniques were then used to elicit a tachycardia, vagal section and atropine administration.

Results:  The increase in blood pressure caused heart rate to fall to 60 ± 7 beats min−1 (mean ± SEM). When the vagi were sectioned (n = 5) heart rate increased by 9 ± 2 beats min−1 above the intrinsic rate which was 108 beats min−1, this increase was not significant. In contrast atropine given (9–20 μg kg−1) (n = 5) during high vagal activity increased heart rate by 81 ± 22 beats min−1 above the intrinsic rate (P < 0.05). To assess if the dose of atropine affects the magnitude of the vagal tachycardia, the right vagus was stimulated electrically at increasing frequencies (2, 4, 8, 16, 32 Hz) before and after increasing doses of atropine (0.02, 0.05, 1 mg kg−1). This reduced the magnitude of the bradycardia; however, the magnitude of the vagal tachycardia was unaffected.

Conclusion:  The vagal tachycardia cannot be elicited without atropine suggesting that it does not play a significant physiological role.
How we do it: Patient participation in cochlear implant selection
Authors: Geyer M. , Seymour F.K. , Stott L. , Lynch C. , Beukes M. , Aleksy W. , Graham J.M.
Published: January 2006

Keypoints

• Involving patients and parents in the choice of their cochlear implant encourages an active role in the process and facilitates ‘bonding’ and ‘ownership’ of the device.

• The most frequent reasons given by patients for selecting a device included cochlear implant comfort and appearance.

• We describe the Implant Programme based at the Royal National Throat, Nose and Ear Hospital, London, and also examine patient satisfaction with the scheme.
The evidence base for the application of contralateral bone anchored hearing aids in acquired unilateral sensorineural hearing loss in adults
Authors: Baguley D.M. , Bird J. , Humphriss R.L. , Prevost A.T.
Published: January 2006

Keypoints

• Acquired unilateral sensorineural hearing loss reduces the ability to localize sounds and to discriminate in background noise.

• Four controlled trials attempt to determine the benefit of contralateral bone anchored hearing aids over contralateral routing of signal (CROS) hearing aids and over the unaided condition. All found no significant improvement in auditory localization with either aid. Speech discrimination in noise and subjective questionnaire measures of auditory abilities showed an advantage for bone anchored hearing aid (BAHA) > CROS > unaided conditions.

• All four studies have material shortfalls:

  (i) the BAHA was always trialled after the CROS aid;

  (ii) CROS aids were only trialled for 4 weeks;

  (iii) none used any measure of hearing handicap when selecting subjects;

  (iv) two studies have a bias in terms of patient selection;

  (v) all studies were underpowered

  (vi) double reporting of patients occurred.

• There is a paucity of evidence to support the efficacy of BAHA in the treatment of acquired unilateral sensorineural hearing loss. Clinicians should proceed with caution and perhaps await a larger randomized trial.

• It is perhaps only appropriate to insert a BAHA peg at the time of vestibular schwanoma tumour excision in patients with good preoperative hearing, as their hearing handicap increases most.
Nonrandom Processes Maintain Diversity in Tropical Forests
Authors: Wills Christopher , Harms Kyle E. , Condit Richard , King David , Thompson Jill , He Fangliang , Muller-Landau Helene C. , Ashton Peter , Losos Elizabeth , Comita Liza , Hubbell Stephen , LaFrankie James , Bunyavejchewin Sarayudh , Dattaraja H. S. , Davies Stuart , Esufali Shameema , Foster Robin , Gunatilleke Nimal , Gunatilleke Savitri , Hall Pamela , Itoh Akira , John Robert , Kiratiprayoon Somboon , de Lao Suzanne Loo , Massa Marie , Nath Cheryl , Noor Md. Nur Supardi , Kassim Abdul Rahman , Sukumar Raman , Suresh Hebbalalu Satyanarayana , Sun I-Fang , Tan Sylvester , Yamakura Takuo , Zimmerman Jess
Published: January 2006

An ecological community's species diversity tends to erode through time as a result of stochastic extinction, competitive exclusion, and unstable host-enemy dynamics. This erosion of diversity can be prevented over the short term if recruits are highly diverse as a result of preferential recruitment of rare species or, alternatively, if rare species survive preferentially, which increases diversity as the ages of the individuals increase. Here, we present census data from seven New and Old World tropical forest dynamics plots that all show the latter pattern. Within local areas, the trees that survived were as a group more diverse than those that were recruited or those that died. The larger (and therefore on average older) survivors were more diverse within local areas than the smaller survivors. When species were rare in a local area, they had a higher survival rate than when they were common, resulting in enrichment for rare species and increasing diversity with age and size class in these complex ecosystems.
The Cellular Basis of a Corollary Discharge
Authors: Poulet James F. A. , Hedwig Berthold
Published: January 2006

How do animals discriminate self-generated from external stimuli during behavior and prevent desensitization of their sensory pathways? A fundamental concept in neuroscience states that neural signals, termed corollary discharges or efference copies, are forwarded from motor to sensory areas. Neurons mediating these signals have proved difficult to identify. We show that a single, multisegmental interneuron is responsible for the pre- and postsynaptic inhibition of auditory neurons in singing crickets (
Gryllus bimaculatus
). Therefore, this neuron represents a corollary discharge interneuron that provides a neuronal basis for the central control of sensory responses.
Freezing as a Path to Build Complex Composites
Authors: Deville Sylvain , Saiz Eduardo , Nalla Ravi K. , Tomsia Antoni P.
Published: January 2006

Materials that are strong, ultralightweight, and tough are in demand for a range of applications, requiring architectures and components carefully designed from the micrometer down to the nanometer scale. Nacre, a structure found in many molluscan shells, and bone are frequently used as examples for how nature achieves this through hybrid organic-inorganic composites. Unfortunately, it has proven extremely difficult to transcribe nacre-like clever designs into synthetic materials, partly because their intricate structures need to be replicated at several length scales. We demonstrate how the physics of ice formation can be used to develop sophisticated porous and layered-hybrid materials, including artificial bone, ceramic-metal composites, and porous scaffolds for osseous tissue regeneration with strengths up to four times higher than those of materials currently used for implantation.
A Novel Adenovirus Type 6 (Ad6)-Based Hepatitis C Virus Vector That Overcomes Preexisting Anti-Ad5 Immunity and Induces Potent and Broad Cellular Immune Responses in Rhesus Macaques
Authors: Capone Stefania , Meola Annalisa , Ercole Bruno Bruni , Vitelli Alessandra , Pezzanera Monica , Ruggeri Lionello , Davies Mary Ellen , Tafi Rosalba , Santini Claudia , Luzzago Alessandra , Fu Tong-Ming , Bett Andrew , Colloca Stefano , Cortese Riccardo , Nicosia Alfredo , Folgori Antonella
Published: January 2006

Success in resolving hepatitis C virus (HCV) infection has been correlated to vigorous, multispecific, and sustained CD8
+
T-cell response in humans and chimpanzees. The efficacy of inducing T-cell-mediated immunity by recombinant serotype 5 adenovirus vector has been proven in many animal models of infectious diseases, but its immunogenicity can be negatively influenced by preexisting immunity against the vector itself. To evaluate the less prevalent adenovirus serotype 6 (Ad6) as an alternative vector for and HCV vaccine development, we have generated serotype 5 and 6 adenoviral vectors directing expression of the nonstructural region of HCV (MRKAd5-NSmut and MRKAd6-NSmut). Immunogenicity studies in mice showed that the two vectors induced comparable T-cell responses but that only MRKAd6-NSmut was not suppressed in the presence of anti-Ad5 immunity. In contrast, preexisting anti-Ad5 immunity dramatically blunted the immunogenicity of the serotype 5-based HCV vector. Furthermore, MRKAd6-NSmut showed equivalent potency, breadth, and longevity of HCV-specific T-cell responses in rhesus macaques as the corresponding Ad5-based vector over a wide range of doses and was capable of boosting DNA-primed animals even if administered at low doses. These data support the use of the MRKAd6-NSmut for anti-HCV immunotherapy and, more generally, for the Ad6 serotype as a better genetic vaccine vehicle than Ad5.
Function of Small Hydrophobic Proteins of Paramyxovirus
Authors: Wilson Rebecca L. , Fuentes Sandra M. , Wang Ping , Taddeo Erica C. , Klatt Alicia , Henderson Andrew J. , He Biao
Published: January 2006

Mumps virus (MuV), a rubulavirus of the paramyxovirus family, causes acute infections in humans. MuV has seven genes including a small hydrophobic (SH) gene, which encodes a type I membrane protein of 57 amino acid residues. The function of the SH protein is not clear, although its expression is not necessary for growth of MuV in tissue culture cells. It is speculated that MuV SH plays a role in viral pathogenesis. Simian virus 5 (SV5), a closely related rubulavirus, encodes a 44-amino-acid-residue SH protein. Recombinant SV5 lacking the SH gene (rSV5ΔSH) is viable and has no growth defect in tissue culture cells. However, rSV5ΔSH induces apoptosis in tissue culture cells and is attenuated in vivo. Neutralizing antibodies against tumor necrosis factor alpha (TNF-α) and TNF-α receptor 1 block rSV5ΔSH-induced apoptosis, suggesting that SV5 SH plays an essential role in blocking the TNF-α-mediated apoptosis pathway. Because MuV is closely related to SV5, we hypothesize that the SH protein of MuV has a function similar to that of SV5, even though there is no sequence homology between them. To test this hypothesis and to study the function of MuV SH, we have replaced the open reading frame (ORF) of SV5 SH with the ORF of MuV SH in a SV5 genome background. The recombinant SV5 (rSV5ΔSH+MuV-SH) was analyzed in comparison with SV5. It was found that rSV5ΔSH+MuV-SH was viable and behaved like wild-type SV5, suggesting that MuV SH has a function similar to that of SV5 SH. Furthermore, both ectopically expressed SV5 SH and MuV SH blocked activation of NF-κB by TNF-α in a reporter gene assay, suggesting that both SH proteins can inhibit TNF-α signaling.
Characterization of the Role of Very Late Expression Factor 1 in Baculovirus Capsid Structure and DNA Processing
Authors: Vanarsdall Adam L. , Okano Kazuhiro , Rohrmann George F.
Published: January 2006

Very late expression factor 1 (VLF-1) of
Autographa californica
multiple nucleopolyhedrovirus is a putative tyrosine recombinase and is required for both very late gene expression and budded virus production. In this report, we show that a
vlf-1
knockout bacmid was able to synthesize viral DNA at levels similar to that detected for a
gp64
knockout bacmid that served as a noninfectious control virus. Additionally, analysis of replicated bacmid DNA by field-inversion gel electrophoresis indicated that VLF-1 is not required for synthesizing high-molecular-weight intermediates that could be resolved into unit-length genomes when cut at a unique restriction site. However, immunoelectron microscopic analysis revealed that in cells transfected with a
vlf-1
knockout bacmid, aberrant tubular structures containing the capsid protein vp39 were observed, suggesting that this virus construct was defective in producing mature capsids. In contrast, rescuing the
vlf-1
knockout bacmid construct with a copy of VLF-1 that carries a mutation of a highly conserved tyrosine (Y355F) was sufficient to restore the production of nucleocapsids with a normal appearance, but not infectious virus production. Furthermore, the results of a DNase I protection assay indicated that the DNA packaging efficiency of the VLF-1(Y355F) virus construct was similar to that of the
gp64
knockout control. Finally, a recombinant virus containing a functional hemagglutinin epitope-tagged version of VLF-1 was constructed to investigate the association of VLF-1 with the nucleocapsid. Analysis by immunoelectron microscopy of Sf-9 cells infected with this virus showed that VLF-1 localized to an end region of the nucleocapsid. Collectively, these results indicate that VLF-1 is required for normal capsid assembly and serves an essential function during the final stages of the DNA packaging process.
Time- and Temperature-Dependent Activation of Hepatitis C Virus for Low-pH-Triggered Entry
Authors: Tscherne Donna M. , Jones Christopher T. , Evans Matthew J. , Lindenbach Brett D. , McKeating Jane A. , Rice Charles M.
Published: January 2006

Hepatitis C virus (HCV) is an important human pathogen associated with chronic liver disease. Recently, based on a genotype 2a isolate, tissue culture systems supporting complete replication and infectious virus production have been developed. In this study, we used cell culture-produced infectious HCV to analyze the viral entry pathway into Huh-7.5 cells. Bafilomycin A1 and concanamycin A, inhibitors of vacuolar ATPases, prevented HCV entry when they were present prior to infection and had minimal effect on downstream replication events. HCV entry therefore appears to be pH dependent, requiring an acidified intracellular compartment. For many other enveloped viruses, acidic pH triggers an irreversible conformational change, which promotes virion-endosomal membrane fusion. Such viruses are often inactivated by low pH. In the case of HCV, exposure of virions to acidic pH followed by return to neutral pH did not affect their infectivity. This parallels the observation made for the related pestivirus bovine viral diarrhea virus. Low pH could activate the entry of cell surface-bound HCV but only after prolonged incubation at 37°C. This suggests that there are rate-limiting, postbinding events that are needed to render HCV competent for low-pH-triggered entry. Such events may involve interaction with a cellular coreceptor or other factors but do not require cathepsins B and L, late endosomal proteases that activate Ebola virus and reovirus for entry.
Multimeric Soluble CD40 Ligand and GITR Ligand as Adjuvants for Human Immunodeficiency Virus DNA Vaccines
Authors: Stone Geoffrey W. , Barzee Suzanne , Snarsky Victoria , Kee Kristin , Spina Celsa A. , Yu Xiao-Fang , Kornbluth Richard S.
Published: January 2006

For use in humans, human immunodeficiency virus (HIV) DNA vaccines may need to include immunostimulatory adjuvant molecules. CD40 ligand (CD40L), a member of the tumor necrosis factor (TNF) superfamily (TNFSF), is one candidate adjuvant, but it has been difficult to use because it is normally expressed as a trimeric membrane molecule. Soluble trimeric forms of CD40L have been produced, but in vitro data indicate that multimeric, many-trimer forms of soluble CD40L are more active. This multimerization requirement was evaluated in mice using plasmids that encoded either 1-trimer, 2-trimer, or 4-trimer soluble forms of CD40L. Fusion with the body of Acrp30 was used to produce the 2-trimer form, and fusion with the body of surfactant protein D was used to produce the 4-trimer form. Using plasmids for secreted HIV-1 antigens Gag and Env, soluble CD40L was active as an adjuvant in direct proportion to the valence of the trimers (1 < 2 < 4). These CD40L-augmented DNA vaccines elicited strong CD8+T-cell responses but did not elicit significant CD4+T-cell or antibody responses. To test the applicability of the multimeric fusion protein approach to other TNFSFs, a 4-trimer construct for the ligand of glucocorticoid-induced TNF family-related receptor (GITR) was also prepared. Multimeric soluble GITR ligand (GITRL) augmented the CD8+T-cell, CD4+T-cell, and antibody responses to DNA vaccination. In summary, multimeric CD40L and GITRL are new adjuvants for DNA vaccines. Plasmids for expressing multimeric TNFSF fusion proteins permit the rapid testing of TNFSF molecules in vivo.
Pulmonary Immunity to Viral Infection: Adenovirus Infection of Lung Dendritic Cells Renders T Cells Nonresponsive to Interleukin-2
Authors: Thiele Allison T. , Sumpter Tina L. , Walker Joanna A. , Xu Qi , Chang Cheong-Hee , Bacallao Robert L. , Kher Rajesh , Wilkes David S.
Published: January 2006

Adenovirus (Ad) infection has been identified as predisposing hosts to the development of pulmonary disease through unknown mechanisms. Lung dendritic cells (DCs) are vital for initiating pulmonary immune responses; however, the effects of Ad infection on primary lung DC have not been studied. In contrast to the effects on bone marrow- and monocyte-derived DCs, the current study shows that Ad infection of murine BALB/c lung DCs in vitro and in vivo suppresses DC-induced T-cell proliferation. The effect of Ad on DCs was not due to a downregulation of major histocompatibility complex or costimulatory molecules. Analysis of the production of interleukin-12 (IL-12), alpha interferon (IFN-α), and IFN-γ by the Ad-infected DCs shows no significant differences over noninfected control lung DCs. Ad-induced suppression was not due to a deficiency of IL-2 or other DC-secreted factors and was dependent on viral protein synthesis, as UV irradiation of Ad abrogated the suppressive effect. Results suggest that Ad-infected DCs induce T cells to be nonresponsive to IL-2 during primary coculture, as the addition of IL-2 in secondary cultures recovered T-cell proliferation. In vivo studies supported in vitro results showing that Ad infection resulted in lung T cells with decreased proliferative ability. This study demonstrates that Ad infection induces local immunoincompetence by altering DC-T-cell interactions.
Novel Pol II Fusion Promoter Directs Human Immunodeficiency Virus Type 1-Inducible Coexpression of a Short Hairpin RNA and Protein
Authors: Unwalla Hoshang J. , Li Hai-Tang , Bahner Ingrid , Li Ming-Jie , Kohn Donald , Rossi John J.
Published: January 2006

We demonstrate a novel approach for coexpression of a short hairpin RNA (shRNA) with an open reading frame which exploits transcriptional read-through of a minimal polyadenylation signal from a Pol II promoter. We first observed efficient inducible expression of enhanced green fluorescent protein along with an anti-rev shRNA. We took advantage of this observation to test coexpression of the transdominant negative mutant (humanized) of human immunodeficiency type 1 (HIV-1) Rev (huRevM10) along with an anti-rev shRNA via an HIV-1-inducible fusion promoter. The coexpression of the shRNA and transdominant protein resulted in potent, long-term inhibition of HIV-1 gene expression and suppression of shRNA-resistant mutants. This dual expression system has broad-based potential for other shRNA applications, such as cases where simultaneous knockdown of mutant and wild-type transcripts must be accompanied by replacement of the wild-type protein.