bluuebunny/crossref_metadata_2025_split huggingface dataset:
Induction mechanisms and modulation of bidirectional burst stimulation‐induced synaptic plasticity in the hippocampus
Authors: Clark Kristin , Normann Claus 
Published: July 2008

AbstractSpike bursting is an important physiological mode of the hippocampus. Whereas the rules of spike timing‐dependent synaptic plasticity are well defined for pairs of single action potentials (APs) and excitatory postsynaptic potentials (EPSPs), long‐term modification of synaptic responses is much less understood for more complex pre‐ and postsynaptic spike patterns. We induced a burst stimulation (BS)‐associated form of synaptic plasticity in rat CA1 hippocampal slices by repeatedly pairing three EPSPs with a burst of APs induced by postsynaptic current injection. In distinct groups of cells, this induction paradigm resulted in long‐term potentiation (LTP), long‐term depression (LTD) or no change in synaptic strength. LTP was N‐methyl‐d‐aspartate receptor‐dependent, whereas LTD could be blocked by a metabotropic glutamate receptor antagonist or inhibition of Ca2+ influx through voltage‐activated Ca2+ channels. LTP was predicted by a more depolarized membrane potential and a higher initial AP frequency. LTD was facilitated by a larger time interval between the last EPSP and its preceding AP. We conclude from these findings that associative BS induces a bidirectional form of long‐term synaptic plasticity that cannot be fully explained by spike timing rules. Postsynaptic membrane potential and Ca2+ influx further influence the sign and magnitude of synaptic modification. LTP and LTD have distinct mechanisms and can be selectively modulated. This supports the concept of two independent coincidence detectors for LTP and LTD, and extends the physiological options to modulate synaptic plasticity and maintain a putative balance between potentiation and depression in synaptic networks.
Relationship between afterhyperpolarization profiles and the regularity of spontaneous firings in rat medial vestibular nucleus neurons
Authors: Saito Yasuhiko , Takazawa Tomonori , Ozawa Seiji 
Published: July 2008

AbstractOur previous in vivo and in vitro whole‐cell patch‐clamp recording studies demonstrated that neurons in the medial vestibular nucleus (MVN) could be characterized on the basis of three electrophysiological properties: afterhyperpolarization (AHP) profile; firing pattern; and response pattern to hyperpolarizing current pulses. In the present study, to clarify which types of the classified MVN neurons correspond to neurons with regular or irregular firing, we investigated their spike discharge patterns using whole‐cell patch‐clamp recording in both in vivo and in vitro preparations. The discharge regularity was related to AHP profiles, and we found that: (i) the coefficient of variation (CV) of interspike intervals during spike discharges was smaller in neurons exhibiting AHP with a slow component [AHP(s+)] than in those without a slow component [AHP(s−)], or with a slow AHP component preceded by afterdepolarization (ADP) [AHP(s+) with ADP]; (ii) the blockade of Ca2+‐dependent K+ channels by 100 nm apamin abolished the slow component and increased the CV in neurons exhibiting AHP(s+); and (iii) the modulation of firing (firing gain) in response to ramp current was larger in neurons exhibiting AHP(s−) than in the other two neuronal types. These results suggest that neurons exhibiting AHP(s+) are regularly discharging neurons with small firing gains to stimulus, neurons exhibiting AHP(s+) with ADP are irregularly discharging neurons with small firing gains, and neurons exhibiting AHP(s−) are irregularly discharging neurons with large firing gains. The regular firing of neurons exhibiting AHP(s+) is attributed to the activation of apamin‐sensitive Ca2+‐dependent K+ channels.
Olfactory deficits in mice overexpressing human wildtype α‐synuclein
Authors: Fleming Sheila M. , Tetreault Nicole A. , Mulligan Caitlin K. , Hutson Ché B. , Masliah Eliezer , Chesselet Marie‐Françoise 
Published: July 2008

AbstractAccumulation of α‐synuclein in neurons of the central and peripheral nervous system is a hallmark of sporadic Parkinson’s disease (PD) and mutations that increase α‐synuclein levels cause familial PD. Transgenic mice overexpressing α‐synuclein under the Thy1 promoter (Thy1‐aSyn) have high levels of α‐synuclein expression throughout the brain but no loss of nigrostriatal dopamine neurons up to 8 months, suggesting that they may be useful to model pre‐clinical stages of PD. Olfactory dysfunction often precedes the onset of the cardinal motor symptoms of PD by several years and includes deficits in odor detection, discrimination and identification. In the present study, we measured olfactory function in 3‐ and 9‐month‐old male Thy1‐aSyn mice with a buried pellet test based on latency to find an exposed or hidden odorant, a block test based on exposure to self and non‐self odors, and a habituation/dishabituation test based on exposure to non‐social odors. In a separate group of mice, α‐synuclein immunoreactivity was assessed in the olfactory bulb. Compared with wildtype littermates, Thy1‐aSyn mice could still detect and habituate to odors but showed olfactory impairments in aspects of all three testing paradigms. Thy1‐aSyn mice also displayed proteinase K‐resistant α‐synuclein inclusions throughout the olfactory bulb. These data indicate that overexpression of α‐synuclein is sufficient to cause olfactory deficits in mice similar to that observed in patients with PD. Furthermore, the buried pellet and block tests provided sufficient power for the detection of a 50% drug effect, indicating their usefulness for testing novel neuroprotective therapies.
Biodiversity of amoebae and amoebae‐resisting bacteria in a drinking water treatment plant
Authors: Thomas Vincent , Loret Jean‐François , Jousset Michel , Greub Gilbert 
Published: July 2008

SummaryThe complex ecology of free‐living amoebae (FLA) and their role in spreading pathogenic microorganisms through water systems have recently raised considerable interest. In this study, we investigated the presence of FLA and amoebae‐resisting bacteria (ARB) at various stages of a drinking water plant fed with river water. We isolated various amoebal species from the river and from several points within the plant, mostly at early steps of water treatment. Echinamoeba‐ and Hartmannella‐related amoebae were mainly recovered in the drinking water plant whereas Acanthamoeba‐ and Naegleria‐related amoebae were recovered from the river water and the sand filtration units. Some FLA isolates were recovered immediately after the ozonation step, thus suggesting resistance of these microorganisms to this disinfection procedure. A bacterial isolate related to Mycobacterium mucogenicum was recovered from an Echinamoeba‐related amoeba isolated from ozone‐treated water. Various other ARB were recovered using co‐culture with axenic Acanthamoeba castellanii, including mycobacteria, legionella, Chlamydia‐like organisms and various proteobacteria. Noteworthy, a new Parachlamydia acanthamoebae strain was recovered from river water and from granular activated carbon (GAC) biofilm. As amoebae mainly multiply in sand and GAC filters, optimization of filter backwash procedures probably offers a possibility to better control these protists and the risk associated with their intracellular hosts.
Tailored surgery for internal and external rectal prolapse: functional results of 268 patients operated upon by a single surgeon over a 21‐year period*
Authors: Pescatori M. , Zbar A. P. 
Published: July 2008

AbstractObjective  Many procedures are used to treat internal (IRP) and external rectal prolapse (ERP). We report the outcome of surgery tailored in accordance with an evolving Unit algorithm over a 21‐year period.Method  Two hundred and sixty‐eight patients (151 IRP and 117 ERP) are reported. Perineal procedures (Delorme’s mucosectomy, Altemeier’s perineal rectosigmoidectomy) were used in frail elderly patients with ERP with abdominal sacrorectopexy or the Frykman‐Goldberg procedure in fit patients. In IRP, prolapsectomy was most common with anterior hemi‐Delorme’s procedures for rectocele and levatorplasty for coincident faecal incontinence. Clinical and functional outcome was assessed over a median of 61 months (range 4–184 months).Results  Postoperative mortality was 0.4%. For ERP, a perineal procedure was carried out in 75 (61.4%) cases with a 7.2% complication rate, postoperative incontinence in 20 (26.7%), constipation in four (5.3%) and recurrence in 12 (16%). For 42 abdominal procedures, the complication rate was 5% with incontinence in 7.1%, constipation in eight (19%) and recurrence in five (11.9%). A perineal operation was used in 89.4% of patients with IRP with incontinence in 10.6%, persistent constipation in 48 (52.7%) and recurrence in 25 (27.5%). The overall incontinence rate was 11% following abdominal and 24% following perineal procedures (P < 0.05). Recurrence of ERP was significantly higher following a perineal operation (P < 0.05).Conclusion  Tailored surgery for ERP achieves satisfactory results in terms of recurrence and functional outcome. For patients with IRP, perineal procedures are associated with a high incidence of recurrence and residual evacuatory difficulty.
Efficacy of the anal fistula plug in complex anorectal fistulae
Authors: Thekkinkattil D. K. , Botterill I. , Ambrose N. S. , Lundby L. , Sagar P. M. , Buntzen S. , Finan P. J. 
Published: July 2008

AbstractObjective  The treatment of complex anorectal and rectovaginal fistulae remains a difficult problem. The options are fistulotomy, setons, fibrin glue and a variety of flap procedures. Recently, there have been several reports of a new plug; the Surgisis® AFP™ plug. Reports from various centres do not give consistent results. The aim of this study was to assess the efficacy of the Surgisis® AFP™ fistula plug in a wide spectrum of patients with anorectal, rectovaginal and pouch vaginal fistulae.Method  Between March 2006 and September 2007, patients with a variety of anal fistulae were selected for fistula plug insertion in the coloproctology units at Leeds, UK, and Aarhus, Denmark. Demographic and fistulae details were obtained. Postoperatively, all patients had a course of oral antibiotics.Results  Forty‐three patients with a median age of 45 (range 18–65) years underwent a total of 45 procedures. Seventy‐five per cent (n = 32) had a fistula secondary to cryptoglandular abscess. Median follow up was 47 (range 12–77) weeks. The success rate for complete healing was 44%. Dislodgement caused failure on 10 (22%) occasions.Conclusion  Our study shows a moderate success rate for treatment with fistula plugs. The complex nature of the fistulae selected may be the reason for the low success rate.
The impact of pre‐ or postoperative radiochemotherapy on complication following anterior resection with en bloc excision of female genitalia for T4 rectal cancer
Authors: Szynglarewicz B. , Matkowski R. , Gisterek I. , Forgacz J. , Lacko A. , Pudelko M. , Kornafel J. 
Published: July 2008

AbstractObjective  The aim of the study was to assess the mortality and morbidity following extended anterior resection with excision of internal female genitalia combined with pre‐ or postoperative chemoradiotherapy in women with extensive rectal cancer.Method  The study included a consecutive series of 21 women with T4 adenocarcinoma of the rectum infiltrating the reproductive organs treated with curative intent between 1997 and 2003. All patients had an extended anterior sphincter preserving resection of the rectum (total mesorectal excision) and hysterectomy with or without posterior vaginal wall excision. In all patients, surgery was combined with adjuvant radiochemotherapy. Ten patients received preoperative radiotherapy (50.4 Gy) concurrently with two courses of chemotherapy [fluorouracil with folinic acid (FA)] followed by surgery within 6–8 weeks and subsequently four courses of postoperative chemotherapy. Eleven received postoperative chemoradiotherapy (50.4 Gy plus fluorouracil with FA).Results  There was no postoperative mortality. Postoperative complications were observed in 57% patients (early in 14% and late in 52%). These included: anterior resection syndrome with anorectal dysfunction in 52% (requiring proximal diversion in 5%), urinary complications in 24% (complete incontinence requiring a permanent catheter in 5%). In addition, postoperative acute bleeding requiring relaparotomy, delayed wound healing caused by superficial infection, anastomotic leakage, prolonged bowel paralysis, benign rectovaginal fistula and anastomotic stricture occurred (5% each). The risk of postoperative morbidity (52%) was similar for patients with or without preoperative radiochemotherapy.Conclusion  Despite this aggressive therapeutic approach, most postoperative complications were transient or could be treated. Preoperative radiochemotherapy did not increase the risk of morbidity.
To determine the efficacy of anal fistula plug in the treatment of high fistula‐in‐ano: an initial experience
Authors: Garg P. 
Published: July 2008

AbstractObjective The aim of this study was to determine the efficacy of the anal fistula plug in the treatment of high fistula‐in‐ano.Method Twenty‐three patients with high cryptoglandular fistula‐in‐ano were prospectively studied over 1 year. The number of tracks, number of previous procedures and co‐morbid conditions that could potentially affect outcome were noted. A seton was used to guide the AFP™ into the fistula track which was anchored at the primary opening.Results Two patients were lost to follow‐up. Twenty‐one patients (mean age was 49.8 years) were followed from 192 to 543 days (median = 292 days). Thirteen patients had single track, eight had multiple tracks and 14 had a recurrent fistula. Success, defined by closure of all fistula tracks occurred in 71.4% (15/21). The success rate was 84.6% in patients with a single fistula track (11/13) compared with 50% in patients with multiple tracks (4/8) (P = 0.14, Fisher’s exact test). Recurrent [10/14 (71.4%)]vsnonrecurrent fistulae [5/7 (71.4%)] had no bearing on the outcome (P = 1.0). Two patients experienced healing despite extrusion of the plug in the early postoperative period. The procedure was safe and well tolerated.Conclusion The Surgisis® AFP™ was successful in 71.4% of patients. Plug extrusion does not necessarily mean failure.
Value of sacral nerve stimulation in the treatment of severe faecal incontinence: a comparison to the artificial bowel sphincter
Authors: Meurette G. , La Torre M. , Regenet N. , Robert‐Yap J. , Lehur P. A. 
Published: July 2008

AbstractObjective  Sacral nerve stimulation (SNS) is a recent treatment option in the management of severe faecal incontinence (FI) that offers promising results. The aim of this study was to compare SNS to artificial bowel sphincter (ABS) implanted patients to assess the rationale of this approach in achieving satisfying functional results and improved quality of life (QoL).Method  Among 27 patients tested (December 2001 and April 2004), 15 patients were successfully managed with SNS. They were compared to 15 matched patients implanted with ABS in a previous period (control group). Assessment of continence level (Cleveland Clinic score), constipation score (Knowles, Eccersley, Scott Score) and QoL (Short‐Form 36) were prospectively collected.Results  Both groups were comparable for clinical parameters (age, gender, anal testing and aetiology of incontinence) and anal physiology. The mean postoperative continence score was significantly higher in the SNS group [9.4 (±3.3) vs 5.7 (±3.9), P < 0.01]; however, the mean constipation score was higher in the ABS group (6.3 ± 6.3 vs 12.8 ± 5.7, P < 0.01). The mean QoL score was similar in both groups. The mean follow‐up after implantation was 15 (±9) months in the SNS group, and 43 (±33) months in the ABS group.Conclusion  In this study, SNS offers satisfying results in terms of QoL, similar to that of ABS. Although it seems to be less effective in restoring continence level, symptoms of outlet obstruction are more frequent after ABS. This SNS approach should be proposed as a first‐line treatment of FI in selected patients. ABS should remain an option that can improve function.
Preoperative neo‐adjuvant therapy for curable rectal cancer – reaching a consensus 2008
Authors: Scott N. A. , Susnerwala S. , Gollins S. , Sun Myint A. , Levine E. 
Published: July 2008

AbstractObjective  Our aim was to determine the range of neo‐adjuvant therapy the multidisciplinary team (MDT) currently offers patients with curable (M0) rectal cancer.Method  A senior oncologist from each of the four oncology centres in north Wales and the north‐west of England (approximate target population 8 million – Glan Clwyd, Clatterbridge, Christie and Preston) reviewed his/her understanding of the current evidence of neo‐adjuvant therapy in rectal cancer. Then a representative from each centre was asked to identify which of three neo‐adjuvant options (no neo‐adjuvant therapy, short‐course radiotherapy 25 Gy over five fractions and long‐course chemoradiotherapy) he/she would use for a rectal cancer in the upper, middle or lower third of the rectum staged by magnetic resonance imaging as being T2–T4 and/or N0–N2.Results  In all cases of locally advanced rectal cancer (T3a N1–T4), oncologists from the four oncology centres recommended long‐course chemoradiotherapy before rectal resection. This consensus was maintained for cases of lower third T3a N0 cancers. Thereafter, the majority of patients with rectal cancer are offered adjuvant short‐course radiotherapy.Conclusion  Neo‐adjuvant therapy is less likely to be offered if the tumour is early (T2, N0) and/or situated in the upper third of the rectum.
Stapled haemorrhoidopexy for the treatment of haemorrhoids: a systematic review
Authors: Burch J. , Epstein D. , Baba‐Akbari Sari A. , Weatherly H. , Jayne D. , Fox D. , Woolacott N. 
Published: July 2008

AbstractObjective  This systematic review aimed to evaluate the short‐ and long‐term safety, efficacy and costs of stapled haemorrhoidopexy (SH) compared with conventional haemorrhoidectomy.Method  We searched 26 electronic databases and websites for studies in any language up to July 2006. Inclusion criteria were predefined, and each stage of the review process was conducted in duplicate.Results  Twenty‐seven randomized controlled trials were included (n = 2279). All had some methodological flaws. Postoperatively, 19 trials (95%) reported less pain, 17 (89%) reported a shorter operating time, 14 (88%) a shorter hospital stay, and 14 (93%) a shorter convalescence time following SH. However, prolapse was significantly more common after SH (OR 3.38; 95% CI: 1.00, 11.47). In the longer term, prolapse was significantly more common after SH (OR 4.34; 95% CI: 1.67, 11.28) as was reintervention for prolapse (OR 6.78; 95% CI: 2.00, 23.00). There were no differences in the rate or type of complications. Conventional haemorrhoidectomy and SH had similar costs during the initial admission.Conclusion  Compared with conventional haemorrhoidectomy, SH resulted in less postoperative pain, shorter operating time, a shorter hospital stay, and a shorter convalescence, but a higher rate of prolapse and reintervention for prolapse.
Rectal cancer: involved circumferential resection margin – a root cause analysis
Authors: Youssef H. , Collantes E. C. , Rashid S. H. , Wong L. S. , Baragwanath P. 
Published: July 2008

AbstractIntroduction  An involved circumferential resection margin (CRM) following surgery for rectal cancer is the strongest predictor of local recurrence and may represent a failure of the multidisciplinary team (MDT) process.Aim of study  The study analyses the causes of positive CRM in patients undergoing elective surgery for rectal cancer with respect to the decision‐making process of the MDT, preoperative rectal cancer staging and surgical technique.Method  From March 2002 to September 2005, data were collected prospectively on all patients undergoing elective rectal cancer surgery with curative intent. The data on all patients identified with positive CRM were analysed.Results  Of 158 patients (male:female = 2.2:1) who underwent potentially curative surgery, 16 (10%) patients had a positive CRM on postoperative histology. Four were due to failure of the pelvic magnetic resonance imaging (MRI) staging scans to predict an involved margin, two with an equivocal CRM on MRI did not have preoperative radiotherapy, one had an inaccurate assessment of the site of primary tumour and in one intra‐operative difficulty was encountered. No failure of staging or surgery was identified in the remaining eight of the 16 patients. Abdominoperineal resection (APR) was associated with a 26% positive CRM, compared with 5% for anterior resection.Conclusion  No single consistent cause was found for a positive CRM. The current MDT process and/or surgical technique may be inadequate for low rectal tumours requiring APR.
Preservation of sexual and bladder function after laparoscopic rectal surgery
Authors: Jones O. M. , Stevenson A. R. L. , Stitz R. W. , Lumley J. W. 
Published: July 2008

AbstractBackground  There have recently been reports of higher levels of bladder and sexual dysfunction in men after laparoscopic rectal surgery when compared with those undergoing open surgery. This has led some surgeons to question the role of the laparoscopic approach to rectal surgery.Method  This study represents a retrospective analysis of a prospectively collected database for a single unit, comprising 2406 patients undergoing laparoscopic colorectal surgery. Bladder function, potency and ejaculation were assessed at postoperative clinic visits for men undergoing laparoscopic low or ultra‐low anterior resection and abdominoperineal excision of the rectum.Results  A total of 101 males were identified (median age 62 years: range 20–90 years). Urinary dysfunction was reported by six (6%) patients. Six (6%) patients had sexual dysfunction, manifesting as retrograde ejaculation in four patients and erectile dysfunction in a further two patients.Conclusions  The low rates of sexual dysfunction in this unit may be attributable to pelvic dissection only being undertaken by experienced, dedicated laparoscopic colorectal surgeons. Laparoscopic restorative surgery for rectal cancer has been performed here only since 2001 after considerable experience accrued in operating on benign rectal disease and colon cancer. Studies from elsewhere reporting poorer functional outcomes have probably included a significant number of patients on the surgeons’‘learning curve’.