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31.
Gene therapy and erectile dysfunction: the current status 总被引:1,自引:0,他引:1
Lau DH Kommu SS Siddiqui EJ Thompson CS Morgan RJ Mikhailidis DP Mumtaz FH 《Asian journal of andrology》2007,9(1):8-15
Current available treatment options for erectile dysfunction (ED) are effective but not without failure and/or side effects. Although the development of phosphodiesterase type 5 (PDE5) inhibitors (i.e. sildenafil, tadalafil and vardenafil) has revolutionized the treatment of ED, these oral medications require on-demand access and are not as effective in treating ED related to diabetic, post-prostatectomy and severe veno-occlusive disease states. Improvement in the treatment of ED is dependent on understanding the regulation of human corporal smooth muscle tone and on the identification of relevant molecular targets. Future ED therapies might consider the application of molecular technologies such as gene therapy. As a potential therapeutic tool, gene therapy might provide an effective and specific means for altering intracavernous pressure "on demand" without affecting resting penile function. However, the safety of gene therapy remains a major hurdle to overcome before being accepted as a mainstream treatment for ED. Gene therapy aims to cure the underlying conditions in ED, including fibrosis. Furthermore, gene therapy might help prolong the efficacy of the PDE5 inhibitors by improving penile nitric oxide bioactivity. It is feasible to apply gene therapy to the penis because of its location and accessibility, low penile circulatory flow in the flaccid state and the presence of endothelial lined (lacunar) spaces. This review provides a brief insight of the current role of gene therapy in the management of ED. 相似文献
32.
PURPOSE: To determine the association of cyclin D1 and E1 expression with bladder cancer presence, clinical and molecular characteristics, and disease progression in patients with nonmuscle-invasive urothelial cell carcinoma of the bladder. METHODS: Immunohistochemical staining for cyclin D1, cyclin E1, p53, p21, p27, pRB, KI-67, and survivin was performed on a tissue microarray containing specimens from 9 normal controls and 74 patients with Ta, Tis, and/or T1 urothelial cell carcinoma of the bladder. Cyclin D1 and E1 immunoreactivity were considered low when samples showed less than 10% and 30% nuclear reactivity, respectively. RESULTS: Normal bladder urothelium from all 9 control patients showed uniformly intense expression of cyclin D1 and cyclin E1. Cyclin D1 and E1 expression were low in 23 of 74 (31.1%) and 27 of 74 (36.5%) specimens. Kaplan-Meier analyses showed that low expression of cyclin E1 was significantly associated with an increased probability of tumor recurrence and progression in univariate, but not multivariate analysis. Cyclin D1 immunoreactivity was not associated with any pathologic characteristics or clinical outcomes. Low cyclin E1 expression was significantly associated with altered expression of p53, pRB, KI-67, and survivin. CONCLUSIONS: Tissue expression of cyclin D1 or E1 seems not to add independent prognostic value to standard features in patients with nonmuscle -invasive urothelial cell carcinoma of the bladder. 相似文献
33.
Alfred L. Rhyne III Leo R. Spector Gary L. Schmidt Luke Madigan Susan M. Odum Bruce V. Darden II Faisal Siddiqui 《European spine journal》2007,16(8):1267-1272
The relationship of the esophagus to the cervical vertebral body (CVB), disc space and longus colli (LC) muscles, to our knowledge,
has not been previously studied. The purpose of this study was to quantify the relationship of the esophagus to the CVB, disc
space and LC. 30 patients were selected for a retrospective review of computed tomography (CT) scans. Measurements between
the esophagus and the C5, C6, and C7 vertebral bodies as well as the C5/6 and C6/7 disc spaces were performed in the midline,
3 mm right and left of midline, and at the edge of the LC on both sides. The closest distance of the esophagus to the CVB
and disc space occurs at the midline (range 1.02–1.31 mm at each level). The furthest distance occurred at the edge of the
right LC (range 2.67–3.30 mm at each level). The mean distance from the edge of the right LC to the midline was significantly
greater (P < 0.01) than mean distance from the edge of the left LC to the midline. No statistical significant differences were observed
when comparing measurements at the individual vertebral bodies and disc spaces. The results of the study demonstrate that
the esophagus lies in closest proximity to the CVB and disc space in the midline. A larger potential space exists between
the esophagus and the CVB and disc space at the edge of the LC. These results may provide insight into a potential cause of
post-operative dysphagia. Furthermore, it may help guide the future design of cervical plates to better utilize the potential
space between the esophagus and the CVB and disc space at the edge of the LC. 相似文献
34.
Transabdominal sacrocolpopexy has been shown, in multiple long-term studies of its success and durability, to be the definitive
treatment option for post-hysterectomy vaginal vault prolapse. It is, however, associated with greater morbidity than vaginal
repair. We describe a minimally invasive technique for vaginal vault prolapse repair and present our experience with a minimum
of one-year follow-up. The surgical technique involves five laparoscopic ports—three for the da Vinci robot and two for the
assistant. After appropriate dissection a polypropylene mesh is attached to the sacral promontory and to the vaginal apex
by use of Gore-Tex sutures. The mesh material is then covered by the peritoneum. Patient analysis focused on complications,
urinary continence, patient satisfaction, and morbidity, with a minimum of 12 months follow-up. Forty-two patients with post-hysterectomy
vaginal vault prolapse underwent robot-assisted laparoscopic sacrocolpopexy at our institute and 35 have a minimum of 12 months
follow-up, with a mean follow-up of 36 months (range 12–48) in the group. Mean age was 67 (47–83) years and mean operating
time was 3.1 (2.15–4.75) h for the entire cohort. All but one patient were discharged home on postoperative day one; one patient
left on postoperative day two. One developed recurrent grade three rectocele, one had recurrent vault prolapse, and two suffered
from vaginal extrusion of mesh. All patients were satisfied with their outcome. The robot-assisted laparoscopic sacrocolpopexy
is a minimally invasive technique for vaginal vault prolapse repair, combining the advantages of open sacrocolpopexy with
the reduced morbidity of laparoscopy. We observed reduced hospital stay, low occurrence of complications, and high patient
satisfaction, with a minimum of 1-year follow-up. Most importantly, the long-term results of the robotic repair are similar
to those of open repair, but with significantly less morbidity. 相似文献
35.
Accuracy of conventional digital palpation and ultrasound of the cricothyroid membrane in obese women in labour 下载免费PDF全文
Success of cricothyroidotomy depends on accurate identification of anatomical neck landmarks. Anaesthetists palpated the cricothyroid membrane of 28 obese and 28 non‐obese women in labour (cut‐off BMI 30 kg.m?2) and marked the entry point for device insertion with an ultraviolet invisible pen. Ultrasonography was used to mark the midpoint of the cricothyroid membrane and the distance between the two marks was measured. The median (IQR [range]) distance between the two marks was significantly greater in the obese than the non‐obese patients (5 (2–9.5 [0–34]) mm vs 1.8 (0.1–6 [0–15]) mm, respectively; p = 0.02). The cricothyroid membrane was accurately identified with digital palpation in only 39% (11/28) of obese compared with 71% (20/28) of non‐obese patients (p = 0.03). Increased neck circumference in obese patients was significantly associated with inaccuracy in locating the cricothyroid membrane. Percutaneous identification of the cricothyroid membrane in obese women in labour was poor. Pre‐procedural ultrasound may help improved the identification of neck landmarks for cricothyroidotomy. 相似文献
36.
Ayman S. Moussa Michael W. Kattan Ryan Berglund Changhong Yu Khaled Fareed J. Stephen Jones 《BJU international》2010,105(3):352-358
Study Type – Diagnostic (exploratory cohort)Level of Evidence 2b
OBJECTIVE
To develop a nomogram to predict the probability that the pathological Gleason sum (GS) will be higher than that indicated by the biopsy, suggesting a higher risk for the patient presumed to be at low risk, as a substantial proportion of patients with low and intermediate grade on biopsy are upgraded on interpretation of the radical prostatectomy (RP) specimens, but a similar clarification of accurate Gleason scoring is not available in patients with no surgical histology.PATIENTS AND METHODS
The study included 1017 patients who had RP after biopsy showing GS 6 and 7 (3 + 4) from 2000 to 2007. Nomogram predictor variables included age, race, digital rectal examination, prostate‐specific antigen (PSA) level, number of cores taken, number of positive cores, maximum percentage cancer in any core, number of previous biopsies, prostate volume, clinical stage, high‐grade prostatic intraepithelial neoplasia, atypical small acinar proliferation, inflammation and perineural invasion. We calculated the nomogram‐predicted probability in each patient. The area under the receiver operating characteristic curve was calculated as a measure of discrimination, and the calibration was assessed graphically.RESULTS
The mean age of the patients was 60 years, the mean PSA level 6.62 ng/mL; 336 patients were upgraded (33%), 623 remained the same (61.3%) and 58 were downgraded (5.7%). A nomogram for predicting the possibility of upgrading was constructed that had a concordance index of 0.68. The nomogram was well calibrated.CONCLUSIONS
Our nomogram for predicting upgrading provides important additional information for deciding on treatment to both the urologist and the patient with low‐ and intermediate‐grade prostate cancer. It might prove useful when the possibility of a more aggressive Gleason variant can change the management, and is especially meaningful when management options other than surgery are selected based on the inability to recognize the true pathological actual GS. 相似文献37.
38.
BACKGROUND: Cerebral cavernomas are rare vascular anomalies and their expansile growth has been considered to be mainly due to recurrent hemorrhages. They are not generally reported to show aggressive behavior.CASE DESCRIPTION: A 27-year-old male presented with headache, visual disturbances, and a 17-year history of seizures. He was known to have a temporal lobe lesion on CT scan, consistent with a diagnosis of cavernous malformation but with no relevant family history. Serial clinical and radiological follow-up revealed a progressive increase in the size of the lesion with formation of a growing cyst of 7 cm in diameter, which produced mass effect, resulting in the clinical picture of cerebral herniation. The patient underwent emergency surgical resection with symptomatic relief. There was no evidence of significant hemorrhage at surgery.CONCLUSION: Cavernous malformations can show expansile growth without any evidence of a presaging hemorrhagic event and, in the manner of a neoplastic lesion, present with raised intracranial pressure and cerebral herniation. 相似文献
39.
K. Vecchiato A. Egloff O. Carney A. Siddiqui E. Hughes L. Dillon K. Colford E. Green R.P.A.G. Texeira A.N. Price G. Ferrazzi J.V. Hajnal D.W. Carmichael L. Cordero-Grande J. OMuircheartaigh 《AJNR. American journal of neuroradiology》2021,42(4):774
BACKGROUND AND PURPOSE:Head motion causes image degradation in brain MR imaging examinations, negatively impacting image quality, especially in pediatric populations. Here, we used a retrospective motion correction technique in children and assessed image quality improvement for 3D MR imaging acquisitions.MATERIALS AND METHODS:We prospectively acquired brain MR imaging at 3T using 3D sequences, T1-weighted MPRAGE, T2-weighted TSE, and FLAIR in 32 unsedated children, including 7 with epilepsy (age range, 2–18 years). We implemented a novel motion correction technique through a modification of k-space data acquisition: Distributed and Incoherent Sample Orders for Reconstruction Deblurring by using Encoding Redundancy (DISORDER). For each participant and technique, we obtained 3 reconstructions as acquired (Aq), after DISORDER motion correction (Di), and Di with additional outlier rejection (DiOut). We analyzed 288 images quantitatively, measuring 2 objective no-reference image quality metrics: gradient entropy (GE) and MPRAGE white matter (WM) homogeneity. As a qualitative metric, we presented blinded and randomized images to 2 expert neuroradiologists who scored them for clinical readability.RESULTS:Both image quality metrics improved after motion correction for all modalities, and improvement correlated with the amount of intrascan motion. Neuroradiologists also considered the motion corrected images as of higher quality (Wilcoxon z = −3.164 for MPRAGE; z = −2.066 for TSE; z = −2.645 for FLAIR; all P < .05).CONCLUSIONS:Retrospective image motion correction with DISORDER increased image quality both from an objective and qualitative perspective. In 75% of sessions, at least 1 sequence was improved by this approach, indicating the benefit of this technique in unsedated children for both clinical and research environments.Head motion is a common cause of image degradation in brain MR imaging. Motion artifacts negatively impact MR image quality and therefore radiologists’ capacity to read the images, ultimately affecting patient clinical care.1 Motion artifacts are more common in noncompliant patients,2 but even in compliant adults, intrascan movement is reported in at least 10% of cases.3 For children who require high-resolution MR images, obtaining optimal image quality can be challenging, owing to the requirement to stay still over long durations needed for acquisition.4 Sedation can be an option, but it carries higher risks, costs, and preparation and recovery time.5In conditions such as intractable focal epilepsy, identification of an epileptogenic lesion is clinically important to guide surgical treatment. However, these lesions can be visually subtle, particularly in children in whom subtle cortical dysplasias are more common.6 Dedicated epilepsy MR imaging protocols use high-resolution 3D sequences to allow better cortical definition and free reformatting of orientation but involve acquisition times in the order of minutes, so data collection becomes more sensitive to motion.7For children in particular, multiple strategies are available for minimizing motion during MR examinations. Collaboration with play specialists using mock scanners and training or projecting a cartoon are good approaches to reduce anxiety.8,9 These tools are not always available in clinical radiology and, even with these strategies, motion can still be an issue.10 Different scanning approaches to correct for intrascan motion have been proposed. Broadly, prospective methods track head motion in real time and modify the acquisition directions accordingly.11 These approaches are applicable to a wide range of sequences but require optical systems with external tracking markers, sometimes uncomfortable or impractical, and extra setup can ultimately result in longer examinations. Furthermore, these approaches may also not be robust to continuous motion.11-13 Retrospective techniques have also been proposed, in some cases relying on imaging navigators that are not compatible with all standard sequences or contrasts.12Here, we use a more general retrospective motion correction technique: Distributed and Incoherent Sample Orders for Reconstruction Deblurring by using Encoding Redundancy (DISORDER). In this method, k-space samples are reordered to enable retrospective motion correction during image reconstruction.14 Our hypothesis is that DISORDER improves clinical MR imaging quality and readability. To assess its use for clinical sequences, we acquired a dedicated epilepsy MR imaging protocol in 32 children across a wide age range. We used both objective image quality metrics and expert neuroradiologist ratings to evaluate the outcome after motion correction. 相似文献