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991.
Steffensen SC Stobbs SH Colago EE Lee RS Koob GF Gallegos RA Henriksen SJ 《Experimental neurology》2006,202(1):139-151
Opiate activation of mu-opioid receptors (muORs) in the ventral tegmental area (VTA) modulates gamma-aminobutyric acid (GABA) neurotransmission within the mesocorticolimbic dopamine (DA) reward system. We combined in vivo extracellular electrophysiological recordings in anesthetized and freely behaving rats with intracellular Neurobiotin filling and immunocytochemistry to characterize the effects of opiates on VTA GABA neurons, evaluate their discharge activity during opiate self-administration, and identify the cellular sites for opiate activation. We identified a subpopulation of VTA GABA neurons that was characterized by location, spike discharge profile, activation by microelectrophoretic DA, and response to internal capsule (IC) stimulation. Systemic administration of heroin or microelectrophoretic application of the selective muOR agonist [d-Ala2, N-Me-Phe4, Gly-ol]-Enkephalin (DAMGO) reduced VTA GABA neuron firing rate (heroin IC(50) = 0.35 mg/kg) and was blocked by the muOR antagonist naloxone. Heroin also reduced IC-evoked post-stimulus spike discharges, a manifestation of gap-junction-mediated electrical coupling between VTA GABA neurons. The baseline firing rate of VTA GABA neurons significantly increased (239%) following the acquisition of heroin self-administration behavior and transiently increased during each response for heroin (105%), but decreased (49%) following heroin, similar to non-contingent heroin. Electrophysiologically characterized VTA GABA neurons were filled with Neurobiotin and labeled dendrites contained plasmalemmal muOR immunoreactivity. Dually labeled muOR dendrites contained dendrodendritic appositions characteristic of gap junctions. These findings indicate that inhibition of this population of GABAergic neurons by opiates acting on dendritic muORs has implications for modulation of electrical coupling between VTA GABA neurons and dopamine (DA) neurotransmission in the VTA and terminal field regions. 相似文献
992.
Plasma serotonin in autism 总被引:1,自引:0,他引:1
Connors SL Matteson KJ Sega GA Lozzio CB Carroll RC Zimmerman AW 《Pediatric neurology》2006,35(3):182-186
Serotonin is necessary for normal fetal brain development. Administration of serotonin inhibitors to pregnant rats results in offspring with abnormal behaviors, brain morphology, and serotonin receptor numbers. Low maternal plasma serotonin may contribute to abnormal brain development in autism. In this study, plasma serotonin levels in autism mothers and control mothers of typically developing children were compared, and plasma serotonin levels in children with autism (n = 17) and their family members were measured. Plasma serotonin levels in autism mothers were significantly lower than in mothers of normal children (P = 0.002). Plasma serotonin levels correlated between autism mothers and their children, but differed between autistic children and their fathers (P = 0.028) and siblings (P = 0.063). Low maternal plasma serotonin may be a risk factor for autism through effects on fetal brain development. 相似文献
993.
The specific impedance of cardiac tissue cannot be measured directly. Instead, the investigator obtains voltage and current
measurements and places them into a model of the tissue's structure to infer the impedances of elements of the model. If the
model fails to describe major aspects of the real tissue, the results may be worthless, although possibly self-consistent.
In the literature of impedance measurement in cardiac tissue, only rarely is the model explicitly described; more commonly,
the tissue model is adopted implicitly when equations giving the impedance in terms of voltage and current measurements are
adopted. This paper examines the series of models that have been used in specific impedance measurements of cardiac tissue
and shows how the same or similar measurements can accurately describe tissue impedivity or can lead to significant errors
when inadequate models such as isotropic and anisotropic monodomains (although a part of work of historical merit) are used. 相似文献
994.
Oscar Suarez David Osborn Melissa Kaufman W. Stuart Reynolds Roger Dmochowski 《Current urology reports》2013,14(6):580-584
Benign prostatic hyperplasia (BPH) is a common cause of lower urinary tract symptoms (LUTS) in men. Patients with BPH often present with a combination of obstructive and overactive bladder (OAB) symptoms. It is postulated that bladder outlet obstruction (BOO) from BPH results in concomitant OAB symptoms through ischemic induced variations in the response to neurotransmitters of both the detrusor and the urothelium. This altered response leads to the pathologic activation of the micturition reflex, generating sensory dysfunction and involuntary bladder contractions. Alpha-1 adrenoceptor antagonists (alpha-blockers) and 5-alpha reductase inhibitors (5-ARIs) are commonly used to treat the BOO caused by BPH. Anticholinergic agents are frequently used to treat concurrently OAB symptoms caused by the BOO. Unfortunately, anticholinergic medications demonstrate bothersome side effects and a theoretical risk of urinary retention. Basic science and clinical research has led to the development of a new class of pharmaceuticals for the treatment of overactive bladder with diminished risk of urinary retention and lacking many anticholinergic side effects. This novel compound, mirabegron (Mybertriq, Astellas Pharma US, Inc.), is a β3-adrenoceptor agonist and represents a promising new class of oral agents designed for the treatment of OAB symptoms, with minimal effect on voiding. 相似文献
995.
恒河猴中TTV感染的回顾性实验研究 总被引:1,自引:0,他引:1
目的:了解接种患者血清的恒河猴能否复制TT病毒(TT virus,TTV),正常恒河猴中是否有TTV感染,分析猴中TTV基因结构特点。方法:用PCR方法检测血清标本中TTV DNA,对TTV DNA阳性的标本进行序列测定。结果:健康猴中无TTV感染;10只接种患者血清的恒河猴中,经验检测有4只为TTV阳性,将其中一株TTV进行序列测定,该序列与日本TTV部分基因相对应位置的核苷酸同源性为96%,将 相似文献
996.
Victor A. Cheuy Jared R.H. Foran Roger J. Paxton Michael J. Bade Joseph A. Zeni Jennifer E. Stevens-Lapsley 《The Journal of arthroplasty》2017,32(8):2604-2611
Background
Arthrofibrosis is a debilitating postoperative complication of total knee arthroplasty (TKA). It is one of the leading causes of hospital readmission and a predominant reason for TKA failure. The prevalence of arthrofibrosis will increase as the annual incidence of TKA in the United States rises into the millions.Methods
In a narrative review of the literature, the etiology, economic burden, treatment strategies, and future research directions of arthrofibrosis after TKA are examined.Results
Characterized by excessive proliferation of scar tissue during an impaired wound healing response, arthrofibrotic stiffness causes functional deficits in activities of daily living. Postoperative, supervised physiotherapy remains the first line of defense against the development of arthrofibrosis. Also, adjuncts to traditional physiotherapy such as splinting and augmented soft tissue mobilization can be beneficial. The effectiveness of rehabilitation on functional outcomes depends on the appropriate timing, intensity, and progression of the program, accounting for the patient's ability and level of pain. Invasive treatments such as manipulation under anesthesia, debridement, and revision arthroplasty improve range of motion, but can be traumatic and costly. Future studies investigating novel treatments, early diagnosis, and potential preoperative screening for risk of arthrofibrosis will help target those patients who will need additional attention and tailored rehabilitation to improve TKA outcomes.Conclusion
Arthrofibrosis is a multi-faceted complication of TKA, and is difficult to treat without an early, tailored, comprehensive rehabilitation program. Understanding the risk factors for its development and the benefits and shortcomings of various interventions are essential to best restore mobility and function. 相似文献997.
George Grammatopoulos Benjamin Kendrick Martin McNally Nicholas A. Athanasou Bridget Atkins Peter McLardy-Smith Adrian Taylor Roger Gundle 《The Journal of arthroplasty》2017,32(7):2248-2255
Background
Debridement-antibiotics-and-implant-retention (DAIR) may be considered a suitable surgical option in periprosthetic joint infections (PJIs) with soundly fixed prostheses, despite chronicity. This study aims to define the long-term outcome following DAIR in hip PJI.Methods
We reviewed all hip DAIRs performed between 1997 and 2013 (n = 122) to define long-term outcome and identify factors influencing it. Data recorded included patient demographics, medical history, type of DAIR performed (+/? exchange of modular components), and organisms identified. Outcome measures included complications and/or mortality rate, implant survivorship, and functional outcome (Oxford Hip Score).Results
Most DAIRs (67%) were of primary arthroplasties and 60% were performed within 6 weeks from the index arthroplasty. Infection eradication was achieved in 68% of the first DAIR procedure. In 32 cases, more than one DAIR was required. Infection eradication was achieved in 85% of the cases (104/122) with the (single or multiple) DAIR approach. The most common complication was PJI-persistence (15%), followed by dislocation (14%). Very good functional outcomes were obtained, especially in primary arthroplasties. All streptococcus infections were resolved with DAIR and had better outcome. Twenty-one hips have been revised (17%) to-date, 16 were for persistence of PJI. The 10-y implant survivorship was 77%. Early PJI and exchanging modular components at DAIR were independent factors for a 4-fold increased infection eradication and improved long-term implant survival.Conclusion
DAIR is, therefore, a valuable option in the treatment of hip PJI, especially in the early postoperative period (≤6 weeks), with good outcomes. However, DAIR is associated with increased morbidity; further surgery may be necessary and instability may occur. Where possible, exchange of modular implants should be undertaken. 相似文献998.
Carolyn Botros Shilpa Iyer Alexis M. Tran Roger P. Goldberg 《International urogynecology journal》2017,28(11):1747-1749
Introduction and hypothesis
Several reports have described vaginal prolapse in Mayer–Rokitansky–Küster–Hauser (MRKH) syndrome patients after creation of a neovagina. To our knowledge, no reports of primary vaginal prolapse of a blind pouch without previous intervention, or surgery for this condition, have been described.Methods
In this case report, we describe a 19-year-old woman with MRKH and complete prolapse of her shortened vaginal pouch. Surgical correction utilizing permanent suture-based sacrospinous ligament fixation was performed.Results
The patient had a successful outcome.Conclusions
Sacrospinous ligament fixation provided a safe and effective method for the management of vaginal pouch prolapse. Long-term follow-up is planned. To our knowledge, this is the first report describing surgical repair of primary prolapse of a blind vaginal pouch in the setting of MRKH.999.
Wassenaar E Johnston N Merati A Montenovo M Petersen R Tatum R Pellegrini C Oelschlager B 《Surgical endoscopy》2011,25(12):3870-3876
Background
Some patients with gastroesophageal reflux disease (GERD) suffer from laryngopharyngeal reflux (LPR). There is no reliable diagnostic test for LPR as there is for GERD. We hypothesized that detection of pepsin (a molecule only made in the stomach) in laryngeal epithelium or sputum should provide evidence for reflux of gastric contents to the larynx, and be diagnostic of LPR. We tested this hypothesis in a prospective study in patients with LPR symptoms undergoing antireflux surgery (ARS). 相似文献1000.
Jennifer L. St Sauver Steven J. Jacobsen Debra J. Jacobson Michaela E. McGree Cynthia J. Girman Ajay Nehra Veronique L. Roger Michael M. Lieber 《BJU international》2011,107(3):443-450
Study Type – Prevention (individual cohort)Level of Evidence 2b What’s known on the subject? and What does the study add? Statin medications reduce inflammation. Inflammation may be important in causing prostate enlargement and lower urinary tract symptoms in aging men. Therefore, statin use may decrease inflammation and help prevent prostate enlargement and lower urinary tract symptoms. Men who took statin medications were less likely to develop an enlarged prostate or lower urinary tract symptoms compared to men who did not take statins. Additionally, men who took statins for the longest period of time had the lowest risk of developing these urological problems. These results suggest that statin use may help prevent common urological problems in aging men.
OBJECTIVE
- ? To determine whether statin use is associated with a decreased risk of developing benign prostatic enlargement (BPE) and lower urinary tract symptoms (LUTS).
SUBJECTS AND METHODS
- ? We conducted a retrospective, population‐based cohort study of 2447 men, 40–79 years of age, residing in Olmsted County, MN, USA, in 1990, and followed these men biennially through 2007.
- ? Cox proportional hazard models were used to assess associations between statin use and new onset of moderate/severe LUTS (American Urological Association Symptom Index score >7), a decreased maximum urinary flow rate (<12 mL/s) or BPE (prostate volume >30 mL).
RESULTS
- ? Statin use was inversely associated with new onset of LUTS (Hazard ratio (HR) 0.39; 95% confidence interval (CI) 0.31–0.49), a decreased maximum flow rate (HR 0.53; 95% CI 0.34–0.82) and BPE (HR 0.40; 95% CI 0.23–0.69) after adjustment for baseline age and body mass index, diabetes, hypertension, coronary heart disease, smoking, alcohol use, activity level and non‐steroidal anti‐inflammatory use.
- ? The longest duration of statin use was associated with the lowest risk of developing each outcome (all tests for trend: P < 0.001).
CONCLUSION
- ? In this study, statin use was associated with a 6.5‐ to 7‐year delay in the new onset of moderate/severe LUTS or BPE.
- ? While men typically take statin medications to prevent coronary heart disease events and related outcomes, these data suggest that men who use statins may also receive urologic benefits.