bluuebunny/crossref_metadata_2025_split huggingface dataset:
Identified spinal motoneurons of young rats possess nicotinic acetylcholine receptors of the heteromeric family
Authors: Ogier R. , Liu X. , Tribollet E. , Bertrand D. , Raggenbass M. 
Published: November 2004

AbstractThe aim of the present study was to determine whether, in young rats, spinal motoneurons possess functional nicotinic acetylcholine receptors. Motoneurons were identified either by retrograde labelling or by choline acetyltransferase immunohistochemistry. Whole‐cell recordings were performed in spinal cord slices cut at the lumbar level. In voltage clamp, acetylcholine evoked a rapidly activating inward current. In current clamp, it depolarized the motoneuron membrane and induced action potential firing. The acetylcholine‐evoked current was strongly reduced by d‐tubocurarine or dihydro‐β‐erythroidine, broad spectrum nicotinic antagonists, but was almost insensitive to methyllycaconitine, a nicotinic antagonist selective for receptors containing the α7 subunit. Moreover, exo‐2‐(2‐pyridyl)‐7‐azabicyclo[2.2.1]heptane, an α7‐specific agonist, was without effect. In young animals, light‐microscopic autoradiography showed that in the central grey matter all laminae were intensely and equally labelled by [3H]epibatidine. A dense [125I]‐α‐bungarotoxin binding was also found in all laminae, with slightly lower levels in the superficial layers of the dorsal horns and in the ventral part of the grey matter. In adults, the density of [3H]epibatidine binding sites was much lower in the entire grey matter, except in layer 2 of the dorsal horn, and [125I]‐α‐bungarotoxin binding sites were present only in some selected areas. Our data indicate that spinal motoneurons possess functional nicotinic receptors of the heteromeric type and suggest that nicotinic cholinergic transmission may play a significant role in the developing spinal cord.
Clinical and biochemical effects of propofol EDTA vs sevoflurane in healthy infants and young children1
Authors: Cohen Ira T. , Finkel Julia C. , Hannallah Raafat S. , Goodale David B. 
Published: November 2004

SummaryBackground : Propofol is frequently used for the induction and maintenance of anaesthesia in children aged 3 years and older. The present study compared the clinical and chemical effects of propofol containing disodium edetate (Diprivan®) with that of sevoflurane in children younger than 3 years of age.Methods : This was an open‐label, comparative, parallel‐group study. Fifty‐six healthy children were randomly assigned to receive either propofol (n = 28; mean age 14.7 months) or sevoflurane (n = 28; mean age 13.2 months) for ambulatory surgical procedures. Anaesthesia was induced with nitrous oxide (60%), oxygen and sevoflurane (8%). In the propofol group, it was followed by an intravenous infusion of propofol at a rate of 200 μg·kg−1·min−1. For the sevoflurane group, anaesthesia was maintained with sevoflurane (1.5–2.5%). Haemodynamic measurements, recovery time and side‐effects were recorded. Ionized calcium and magnesium concentrations in blood were measured. Statistical analysis was performed using ancova and the Fisher's exact test.Results : The effects of propofol were similar to those of sevoflurane with respect to haemodynamic profile, recovery times (20 min vs 19.4 min) and side‐effects (i.e. vomiting 10.7% vs 7.1%). Throughout the study, there were no significant differences between the mean ionized calcium and ionized magnesium concentrations in the two groups.Conclusions : In children younger than 3 years of age, propofol containing ethylenediaminetetraacetic acid has a similar profile to sevoflurane with respect to haemodynamic effects, recovery times, side‐effects, ionized calcium and ionized magnesium levels.
The clinical effect of mixing different proportions of rocuronium and mivacurium
Authors: Fletcher James E. , Heard Christopher M.B. 
Published: November 2004

SummaryBackground : A synergistic effect has been described when rocuronium (Roc) and mivacurium (Miv) are combined in equal (i.e. 1 : 1) ED95 proportions at various total doses. We have investigated the effect of Roc or Miv alone and four different ratios (1 : 4, 2 : 3, 3 : 2 and 4 : 1) of Roc and Miv mixed to a total dose of 1.33 × ED95. The primary outcome is the ratio producing the maximum enhancement of duration of clinical effect.Methods : Sixty‐eight healthy children were anaesthetized with propofol, nitrous oxide and fentanyl. They then randomly received either Roc 0.4 (mg·kg−1), Miv 0.133 (mg·kg−1) or one of four Roc + Miv combinations (mg·kg−1): Roc 0.32 + Miv 0.027; Roc 0.24 + Miv 0.053; Roc 0.16 + Miv 0.08; and Roc 0.08 + Miv 0.106. The mechanical response of the adductor pollicis muscle to supramaximal stimulation of the ulnar nerve at the wrist was recorded.Results : Duration of effect was greater in the combination groups than that predicted from the duration of Roc or Miv used alone. Duration was maximally increased around a 1 : 1 ratio (2 : 3 and 3 : 2) of Roc and Miv. The likelihood of achieving 100% block was greater in combination groups compared with Roc or Miv used alone.Conclusions : Combinations of Roc and Miv show a synergistic effect, which appears maximal as the mixture approaches a 1 : 1 ratio of their ED95s. This combination acted as if a larger effective dose of a single (new) drug had been given, but did not offer the advantage of both rapid onset and short duration of effect.
Incidence and risk factors of perioperative respiratory adverse events in children undergoing elective surgery
Authors: Mamie Chantal , Habre Walid , Delhumeau Cécile , Barazzone Argiroffo Constance , Morabia Alfredo 
Published: November 2004

SummaryBackground:  Adverse respiratory events remain one of the major causes of morbidity during anaesthesia, especially in children. The purpose of this prospective study was to determine the incidence of perioperative respiratory adverse events (PRAE) during elective paediatric surgery and to identify the risk factors for these events.Methods:  Potential risk factors (atopy, eczema, rhinitis, food allergy, previous allergic tests, pollens or animal allergy, passive smoking, obstructive sleep disorders) were assessed using the International Society on Allergy and Asthma (ISAAC) questionnaire, which was submitted to the parents during preoperative anaesthetic assessment. Anaesthetic and surgical conditions were systematically recorded. A multivariate logistic regression explaining PRAE was developed in 800 children.Results:  The intraoperative incidence of respiratory adverse events was 21% and the incidence in the postanesthetic care unit was 13%. According to the multivariate analysis, children not anaesthetized by a specialist paediatric anaesthesiologist have 1.7 increased risk to present PRAE (95% CI = 1.13–2.57). Children anaesthetized for ear, nose, throat (ENT) surgery had a 1.57‐fold higher risk of PRAE compared with other procedures (95% CI = 1.01–2.44). Furthermore, there was a synergistic interaction when two risk factors: residents and ENT surgery, were concomitant: the odds ratio (OR) of PRAE during non‐ENT surgical procedures was 1.43 (95% CI = 0.91–2.24), but increased to 2.74‐fold (95% CI = 1.15–4.32) for ENT surgery. The risk of PRAE was significantly lower when the anaesthetic technique included tracheal intubation with relaxants (OR = 0.6, 95% CI = 0.45–0.95) and decreased by 8% with each increasing year of age.Conclusions:  This study demonstrates a high incidence of PRAE in paediatric surgical patients without respiratory tract infections, which appears to be primarily determined by the age of the child and the anaesthetic care rather than by the child's medical history.
Habitat loss and the limits to endangered species recovery
Authors: Kerr Jeremy T. , Deguise Isabelle 
Published: November 2004

AbstractCanada is one of the last places on earth with extensive wilderness areas, yet the number of Canadian species threatened with extinction continues to rise every year. Using satellite‐derived land use data, we find that habitat loss explains most of the variation in numbers of endangered species across Canada. Habitat loss within species ranges is, therefore, likely to be the leading factor inhibiting their recovery. We measured habitat loss individually within the known ranges of 243 terrestrial species at risk of extinction across Canada. Recovery potential, as measured by extent of natural habitat within each species’ range, is bimodally distributed, but less than 50% of the range of the majority of Canada's species at risk is natural habitat and there is no detectable habitat remaining for 16 of the 243 species at risk. There were no differences in the recovery potential of species categorized either by threat level (special concern, threatened, or endangered) or taxon. Despite having extensive wilderness areas, Canada has similar rates of endangerment to other countries in the Americas, underlining the effect of severe habitat loss to intensive agriculture that has occurred in Canada's most biologically diverse regions. Improvements to protected areas networks and especially cooperative conservation activities with private landowners will do the most to improve the recovery prospects of species at risk in Canada.
Conceptual issues in local adaptation
Authors: Kawecki Tadeusz J. , Ebert Dieter 
Published: November 2004

AbstractStudies of local adaptation provide important insights into the power of natural selection relative to gene flow and other evolutionary forces. They are a paradigm for testing evolutionary hypotheses about traits favoured by particular environmental factors. This paper is an attempt to summarize the conceptual framework for local adaptation studies. We first review theoretical work relevant for local adaptation. Then we discuss reciprocal transplant and common garden experiments designed to detect local adaptation in the pattern of deme × habitat interaction for fitness. Finally, we review research questions and approaches to studying the processes of local adaptation – divergent natural selection, dispersal and gene flow, and other processes affecting adaptive differentiation of local demes. We advocate multifaceted approaches to the study of local adaptation, and stress the need for experiments explicitly addressing hypotheses about the role of particular ecological and genetic factors that promote or hinder local adaptation. Experimental evolution of replicated populations in controlled spatially heterogeneous environments allow direct tests of such hypotheses, and thus would be a valuable way to complement research on natural populations.
Determinants of long‐term quality of life and voiding function of patients treated with radical prostatectomy or permanent brachytherapy for prostate cancer
Authors: Bradley Emily B. , Bissonette Eric A. , Theodorescu Dan 
Published: November 2004

OBJECTIVETo assess the long‐term quality of life (QoL) outcomes of three treatments for localized prostate cancer: radical prostatectomy (RP); brachytherapy monotherapy (BTM); and BT combined with external beam radiotherapy (BTC).PATIENTS AND METHODSIn August 2000, questionnaires were mailed to men with T1c‐T3 adenocarcinoma of the prostate treated with either RP, BTM (103Pd monotherapy) or BTC. Questionnaires included validated outcome measures, i.e. the Functional Assessment of Cancer Therapy − General (FACT‐G), American Urological Association Symptom Score (AUA‐SS), Urinary Function Questionnaire for men after RP, and the Brief Sexual Function Inventory. Returned questionnaires were assessed using cross‐sectional analysis.RESULTSData from 214 patients were included in the analysis (60 RP, 102 BTM and 52 BTC); the median follow‐up was 18.8, 25.5 and 29.9 months, respectively. There were differences between both BT groups and the RP group in total AUA‐SS and obstructive subscale symptom scores, with the former having worse symptom scores at a longer follow‐up. Differences in overall QoL were not detected between groups using the total FACT‐G but the BTC group generally had worse scores in the physical well‐being subscale. The BT groups had higher continence rates with time after treatment. Sexual function was better with BT initially, but these differences did not persist at a longer follow‐up. There were significant correlations between the FACT‐G and the urinary symptom scores, and the degree of sexual function.CONCLUSIONSAlthough patients treated with BTM and RP have a different spectrum of side‐effects, their overall long‐term QoL is similar, with urinary and sexual function being the primary determinants of this outcome. Men treated with BTC have a worse QoL.
Bleeding after transrectal ultrasonography‐guided prostate biopsy: a study of 7‐day morbidity after a six‐, eight‐ and 12‐core biopsy protocol
Authors: Ghani Khurshid R. , Dundas Derek , Patel Uday 
Published: November 2004

OBJECTIVETo compare, in a prospective study, bleeding (in three categories, i.e. haematuria, haematospermia and rectal) and consultations with the general practitioner (GP), after a six‐, eight‐ or 12‐core prostate biopsy, as data on whether taking more prostate core biopsies increases bleeding complications are not conclusive.PATIENTS AND METHODSOver a 5‐year period, patients undergoing outpatient transrectal ultrasonography (TRUS)‐guided prostate biopsy (six, eight or 12‐core biopsy) completed a self‐administered questionnaire. The prevalence and duration of the three bleeding complications and GP or hospital visits for a biopsy‐related complication were assessed and compared for the 7 days after biopsy. The contribution of local anaesthetic (LA) injection to bleeding rates was also assessed.RESULTSOf 1384 patients biopsied, 1000 were given questionnaires and 884 (88%) forms were returned. Of these, 760 were suitable for analysis (307 after six‐core, 325 eight‐core and 128 12‐core biopsies); 351 patients were given LA before biopsy. The prevalence of bleeding complications (six‐, eight‐ and 12‐core, respectively) was: haematuria 44%, 41% and 39%; haematospermia 13%, 16% and 12%; and rectal bleeding 17%, 26% and 27%. Rectal bleeding was significantly more prevalent in the eight‐ and 12‐core groups (P = 0.0037 and 0.019). The duration of bleeding was not significantly greater in any biopsy group. Subgroup analysis showed no significant difference in the prevalence and duration of rectal bleeding after LA. About 5% of patients in each group consulted their GP because of a complication and 2.4% consulted because of bleeding. Three men with major complications required hospitalization, of which only one was caused by bleeding.CONCLUSIONSOnly rectal bleeding was more prevalent after taking more than six cores, but the duration was no greater. Giving LA did not affect the rectal bleeding rate. With all strategies the major complication and hospitalization rate was very low.
Drivers and barriers to seeking treatment for erectile dysfunction: a comparison of six countries
Authors: Shabsigh Ridwan , Perelman Michael A. , Laumann Edward O. , Lockhart Daniel C. 
Published: November 2004

Associate EditorMichael G. WyllieEditorial BoardIan Eardley, UKJean Fourcroy, USASidney Glina, BrazilJulia Heiman, USAChris McMahon, AustraliaBob Millar, UKAlvaro Morales, CanadaMichael Perelman, USAOBJECTIVETo identify predictors of treatment‐seeking behaviour in men with erectile dysfunction (ED) and the predictors (correlates) of individual drivers and barriers to seeking treatment. Although the prevalence and epidemiology of ED have been reviewed, there is little information about the treatment‐seeking behaviour of men with this disorder.SUBJECTS AND METHODSData from the Cross‐National Survey on Male Health Issues conducted between March and September 2000 were assessed by multivariate analysis. A cohort of 32 644 men aged 20–75 years was recruited during visits to their physicians. The men completed a short screening questionnaire, covering their overall health, and prostate, urinary and erectile problems. Men identified as having ED completed a detailed follow‐up questionnaire. Logistic regression methods were used to identify predictors of treatment‐seeking behaviour, and individual drivers and barriers to seeking treatment.RESULTSMost men with ED had not sought treatment. The analyses suggested that ED, in conjunction with a desire to have sex, was necessary for men to seek treatment. Men seeking treatment commonly identified themselves as self‐motivated or that they were influenced by a spouse or sex partner. The youngest group (20–39 years) was least likely to seek treatment. Among those who did not seek treatment, younger men were likely to believe that their ED would resolve spontaneously, whereas older men resisted seeking treatment because they felt that ED was a natural part of ageing.CONCLUSIONSThe data from this survey of men using the healthcare system confirmed other population‐based reports that a minority of men with ED seek treatment. Subset analyses showed that treatment‐seeking behaviour tended to be driven primarily by the man or by his sex partner. Common barriers to seeking treatment included the belief that ED would resolve spontaneously (younger men) and that ED was a normal part of ageing (older men).
The reliability of clinical and biochemical assessment in symptomatic late‐onset hypogonadism: can a case be made for a 3‐month therapeutic trial?
Authors: Black Angela M. , Day Andrew G. , Morales Alvaro 
Published: November 2004

OBJECTIVETo assess whether testosterone (T) supplementation in men considered to have symptomatic late‐onset hypogonadism (SLOH) can be evaluated clinically and biochemically.PATIENTS AND METHODSTo assess the relevance of the clinical and biochemical diagnosis of hypogonadism we investigated patients referred for the diagnosis and treatment of SLOH. Patients were assessed clinically and completed a screening questionnaire. The pituitary‐adrenal‐gonadal axis was comprehensively assessed biochemically. Those with a clinical diagnosis of hypogonadism and serum levels of T supporting such a diagnosis received exogenous T for ≥ 3 months and were assessed for any clinical and biochemical response. Of an initial group of 45 men (mean age 59.2 years) 38 completed the study.RESULTSMost men presented with symptoms of sexual dysfunction, lack of energy and/or depression. There were differences before and after treatment only in bioavailable T (BT), with none in the levels of total T (TT). There was a strong correlation before and after treatment in the levels of luteinizing hormone and follicle‐stimulating hormone, and a weak negative correlation between gonadotrophins and BT. Neither TT nor BT had predictive value for the treatment response. There was a trend to a correlation between BT levels and treatment success. Changes in serum prostate specific antigen were insignificant during the limited period.CONCLUSIONThe lack of accurate methods for diagnosing SLOH suggests that a therapeutic trial of T supplementation is warranted in men in whom there are no contraindications. The 3‐month period largely circumvents the placebo effect and has minimal risks for serious adverse effects (mostly in relation to prostate safety). This controversial position needs further evaluation with a larger cohort and other biochemical measurements.
A prospective study of the predictive power of spiral computed tomographic angiography for defining renal vascular anatomy before live‐donor nephrectomy
Authors: Lewis Gareth R. , Mulcahy Kevin , Brook Nicolas R. , Veitch Peter S. , Nicholson Michael L. 
Published: November 2004

The advent of laparoscopic donor nephrectomy for renal transplantation has focused minds to an even greater degree on the vascular anatomy of the donor kidney. The authors from Leicester determined the accuracy of spiral CT imaging for donor venous anatomy and comparing it to the operative findings, either at open or laparoscopic donor nephrectomy. They found the technique to be an excellent way of assessing potential renal donors in terms of the gonadal and adrenal veins, but less so for predicting lumbar veins.OBJECTIVETo determine the accuracy of spiral computed tomography (CT) imaging of donor venous anatomy by comparing CT angiography (CTA) and operative findings, for both laparoscopic (LDN) and open donor nephrectomy.PATIENTS AND METHODSLDN presents unique surgical challenges, particularly with complex venous or arterial anatomy. The limitations of surgical access, poor visibility of the superior and posterior borders of the renal vein during LDN, and the variability of venous anatomy in this region, contribute to the difficulty of LDN, underlining the importance of imaging beforehand. Forty live donors (mean age 46 years, sd 11; 65% female) were assessed by CTA before donation. Scans were reported by the same radiologist. The number and diameter of ‘predicted’ renal arteries, veins and renal vein tributaries were documented. The donor kidney was removed by two consultant surgeons, and after back‐table perfusion the same details were recorded and taken as the ‘reference’ findings. Tributaries of <1 mm diameter were not recorded. The right kidney was retrieved in seven patients; 25 of the 40 kidneys were retrieved by LDN and the other 15 by open surgery.RESULTSIn all, 48 actual renal arteries were identified at nephrectomy; of these, 47 were predicted by CTA. Likewise, 41 actual renal veins were found at nephrectomy, 40 of which were predicted. The overall accuracy of spiral CTA in predicting the presence or absence of renal vein tributaries was 83% for gonadal and adrenal veins, and 75% for lumbar veins. There were seven false‐negative lumbar veins found at nephrectomy; in these cases the CTA films were retrospectively examined, and five of these seven veins were identified. The predicted renal vein tributary diameter correlated poorly with the measured diameter at nephrectomy.CONCLUSIONSAssessing potential renal donors before surgery with spiral CTA provides an accurate prediction of the presence or absence of the gonadal and adrenal vein, but is less accurate for predicting lumbar veins. This is especially pertinent as the posterior lumbar tributaries have the most intra‐individual variation, and are the most difficult to display and control at LDN. This highlights the need for meticulous dissection of the renal vein, particularly along its posterior wall.
Urethral replacement: a comparison between small intestinal submucosa grafts and spontaneous regeneration
Authors: El‐Assmy Ahmed , El‐Hamid Mohamed Abd , Hafez Ashraf T. 
Published: November 2004

OBJECTIVETo evaluate the use of commercially available single‐layer small intestinal submucosa (SIS) for urethral replacement, both as an onlay and as a tube, in a rabbit model.MATERIALS AND METHODSThirty‐six male rabbits were assigned to four experimental groups. Group 1 had the ventral wall of the penile urethra excised for 15 mm; in group 2 this created defect was patched with a SIS onlay graft; group 3 had complete excision of a 15 mm segment of the penile urethra; and in group 4, this created defect was replaced with a SIS tube graft. In all rabbits the urethra was stented for 2 weeks. A retrograde urethrogram was taken in all rabbits before death at 3, 6 and 12 weeks after surgery. The urethra was then exposed, examined carefully and excised for histopathological examination.RESULTSIn groups 1 and 2 the retrograde urethrograms were normal in 13 rabbits and there was relative narrowing in two rabbits in group 1 and three in group 2. In groups 3 and 4 all rabbits developed urethral fistulae or strictures. Histological examination of the urethra showed epithelial regeneration supported by smooth muscle backing in all rabbits in group 1, while rabbits in group 2 showed no regeneration of smooth muscle. By contrast, rabbits in groups 3 and 4 showed incomplete regeneration and progressive fibrosis.CONCLUSIONSSingle‐layer SIS is not a suitable urethral substitute in this animal model. When used as an onlay, healing is inferior to spontaneous urethral regeneration, as SIS impedes smooth muscle cell regeneration. When used as a tube, there is complete scarring and urethral luminal occlusion.