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61.
AIMS: To determine alterations which occur in the size and shape of lamina cribrosa (LC) pores in glaucomatous eyes over a period of time. METHODS: Baseline and follow up optic disc photographs were retrospectively studied in 39 eyes of 39 patients with glaucoma. Only eyes with a vertical cup to disc ratio equal to or greater than 0.6 were included in the study. In addition, all selected eyes had to have serial optic disc photographs obtained at least 3 years apart allowing clear visualisation of LC surface. The association of the alterations in LC surface morphology with patient specific and eye specific characteristics was statistically analysed. RESULTS: During a mean study period of 3.90 (SD 0.7) years, individual pore size (mean pore area to disc area ratio) exhibited a significant decrease between baseline and follow up measurements of each eye (p<0.0001). However, during the study period, total pore area to disc area ratio did not change (p>0.05), and the change in pore shape in some eyes (from circular to more oval and elongated) was statistically insignificant (p = 0.12). Although a relation was detectable between the optic disc and lamina cribrosa parameters at a given time, which reflects cumulative effects, during the study period, there was no significant association between the changes of the LC parameters and neural tissue damage. The rate and the magnitude of the changes in individual pore size during the study period were not significantly different among the eyes exhibiting progressive neural rim damage and those staying stable (p>0.05). CONCLUSION: These findings demonstrate that the LC surface morphology exhibits changes along with the glaucomatous optic disc damage. However, the clinical appearance of LC surface in glaucomatous eyes may continue to change, even when the neural rim damage is clinically stable. These findings are probably associated with the chronic cellular events of tissue remodelling that occur in the glaucomatous optic nerve head. 相似文献
62.
Female reproductive health after ileal pouch anal anastomosis for ulcerative colitis 总被引:1,自引:0,他引:1
Ileal pouch anal anastomosis is the surgical treatment of choice for ulcerative colitis, offering intestinal continuity and fecal continence. IPAA does not seem to affect menstrual function or gynecologic symptoms. Overall sexual satisfaction may be improved with surgery, although ability to experience orgasm and coital frequency remain essentially unchanged. However, dyspareunia seems to increase postoperatively. Fertility is also adversely affected by IPAA, possibly a result of pelvic adhesions. Pregnancy is characterized by a transient increase in day and night stool frequency and incontinence that resolves after delivery. The ideal route of delivery has not been determined, but vaginal delivery seems safe and does not directly cause pouch dysfunction. TARGET AUDIENCE: Obstetricians & Gynecologists, Family Physicians. LEARNING OBJECTIVES: After completion of this article, the reader will be able to describe the procedure ileal pouch anal anastomosis, to summarize the effects of IPAA on menstrual function and sexual health, and to outline the association of IPAA and infertility. 相似文献
63.
Pinette MG Blackstone J Wax JR Cartin A 《American journal of obstetrics and gynecology》2002,187(6):1721-1722
A fetus with mature amniotic fluid lung indices was delivered with subsequent respiratory distress syndrome, demonstrating that fetal pulmonary maturity needs to be viewed as a probability. We calculated the probability of respiratory distress as a function of gestational age and fetal lung maturity. The percent risks are displayed in an easily readable table format. 相似文献
64.
Wax MK Rosenthal EL Takaguchi R Cohen JI Andersen PE Futran N 《Archives of otolaryngology--head & neck surgery》2002,128(3):249-252
BACKGROUND: Atelectasis is one of the most common postoperative complications encountered in head and neck surgery. Risk factors include preexisting pulmonary disease, the procedure performed, and the length of anesthetic. Regional flaps used to reconstruct defects in the head and neck predispose to radiographic atelectasis. The rectus abdominis myocutaneous flap is usually transferred as a free tissue transfer. Harvesting the flap results in abdominal wall pain and postoperative splinting that may contribute to an increased development of atelectasis. To our knowledge, this issue has not been previously examined. DESIGN: Retrospective review. RESULTS: Fifty-three patients underwent rectus abdominis myocutaneous free flap reconstruction following major ablative procedures for head and neck cancer. The flap size ranged from 5 x 7 to 25 x 27 cm. Most flaps were 8 x 15 cm. The cutaneous area transferred ranged from 35 to 600 cm(2) (mean, 120 cm(2)). These patients were compared with a group of 53 patients who were matched for age, sex, length of the procedure, and stage of disease. Postoperative atelectasis was radiographically detected in 37 (70%) of the patients who underwent rectus abdominis myocutaneous free flap reconstruction vs 41 (77%) of the controls. Major atelectasis was not encountered in any patient in either group. Patients with a larger cutaneous paddle (>120 cm(2)) had a higher atelectasis score than patients with smaller cutaneous paddles (< or =120 cm(2)) (P =.02). CONCLUSIONS: The incidence of radiographic postoperative atelectasis in patients undergoing rectus abdominis myocutaneous free tissue transfer is high. The degree of atelectasis is small, and the clinical correlation and relevance are minimal. 相似文献
65.
OBJECTIVE: The radial forearm free flap has become the method of choice for reconstruction of head and neck defects following oncologic ablation. Harvesting of a radial forearm free flap leaves a donor site defect. This is most commonly closed with a split-thickness skin graft. Morbidity, most commonly owing to a lack of graft take over the tendons, can be quite high. Recently, an acellular matrix (Alloderm) has been advocated to decrease complications at the radial forearm donor site, as well as obviate taking a split-thickness skin graft from the thigh. MATERIAL AND METHODS: Tertiary referral academic centre. Retrospective chart review of 15 patients. Five patients received allogenic dermis, 10 patients received split-thickness skin grafting to the radial forearm donor site. RESULTS: Patients with allogenic dermis took between 12 and 16 weeks to heal completely. Patients undergoing split-thickness skin graft were completely healed within 4 to 6 weeks. Cosmesis was judged to be marginally better in the allogenic dermis group. Allogenic dermis placement had a greater impact on hand function owing to prolonged healing, whereas patients with split-thickness skin graft required wound care at the thigh for a 2- to 3-week period owing to the harvesting of the skin graft. CONCLUSIONS: Allogenic dermis may be a viable alternative to split-thickness skin grafting and radial forearm free flap donor sites. Prolonged healing with subsequent increased health care services use needs to be addressed. 相似文献
66.
Enlarged fetal bladder: Differential diagnosis and outcomes 总被引:1,自引:0,他引:1
The sonographic finding of an enlarged fetal bladder may simply be a transitory normal variant, but it may also be secondary to reflux or to obstructive, neurogenic, or myopathic causes. In this report, we describe the cases of 3 fetuses with an enlarged bladder, each of which had a different cause. The first fetus had posterior urethral valve obstruction, the second, a ruptured neurogenic bladder, and the third, megacystic-microcolon-intestinal hypoperistalsis syndrome. When sonographic examination reveals an enlarged fetal bladder, the ureter, kidneys, genitalia, and spine should be evaluated carefully. Although sonography is good at identifying urinary tract abnormalities, it often cannot provide the specific diagnosis or cause. We recommend frequent sonographic monitoring to evaluate such fetuses for persistence of or changes in bladder enlargement and for changes in the volume of amniotic fluid because these signs may be indicators of abnormalities of renal function and risk factors for a poor prognosis. Analysis of fetal electrolyte levels can also aid in determining the prognosis and whether the condition is amenable to therapeutic intervention. 相似文献
67.
Usefulness of troponin I as a marker of myocardial injury after pediatric cardiac catheterization 总被引:5,自引:0,他引:5
Cardiac troponin I (cTnI) is a sensitive and specific marker of myocardial injury. The degree of myocardial injury associated with pediatric cardiac catheterization is unknown. We sought to investigate cTnI after pediatric cardiac catheterization, and to evaluate the degree of elevation observed with specific types of interventions. Seventy-three pediatric catheterizations were evaluated. Diagnostic procedures and interventions not expected to cause myocardial injury were assigned to group I, whereas interventional procedures expected to be associated with cardiac injury were assigned to group II. Group II procedures were further subdivided based on type of intervention. Serum samples were obtained before and after all procedures and analyzed for cTnI. Postprocedure cTnI levels were compared across groups and correlated with age and weight. Procedures in group II were associated with significantly higher cTnI levels than group I (median 2.65 ng/ml; interquartile range 0.9 to 4.9 ng/ml for group II vs 0.3; 0.3 to 1.6 ng/ml for group I, p <0.001). Within group II, cTnI was inversely correlated with age (p <0.05) and weight (p <0.05). Radiofrequency catheter ablation (RFA) caused higher cTnI levels than other types of interventions (median 3.7 ng/ml; 1.9 to 9.5 ng/ml for RFA vs 1.75; 0.7 to 4.9 ng/ml for non-RFA, p <0.05). Most pediatric interventional catheterization procedures are associated with myocardial injury, as evidenced by elevation of cTnI, with RFA causing higher levels than other interventions. Conversely, most diagnostic procedures are associated with no detectable myocardial injury. When compared with adult studies, pediatric patients seem to be at higher risk for myocardial injury from interventional cardiac catheterization. 相似文献
68.
Interleukin-10 receptor signaling through STAT-3 regulates the apoptosis of retinal ganglion cells in response to stress 总被引:6,自引:0,他引:6
Boyd ZS Kriatchko A Yang J Agarwal N Wax MB Patil RV 《Investigative ophthalmology & visual science》2003,44(12):5206-5211
PURPOSE: Interleukin (IL)-10 has recently been shown to promote survival of neurons and glia. The purpose of this report is to investigate whether IL-10 has any role in protecting retinal ganglion cells (RGCs) from death under conditions in which growth factors are removed, or in which oxidative stress is present. Signal transduction pathways that activate IL-10 signaling in RGCs were studied in both stress conditions. METHODS: Effects of various interleukins on the viability of the RGC cell line was determined, and apoptotic cells were quantified. Immunoblot analysis was preformed to identify the IL-10 receptor (IL-10R) and phosphorylated or nonphosphorylated Akt and STAT-3 proteins in RGC extracts. Immunohistochemistry was performed on the rat retinal sections to identify native IL-10R. RESULTS: Apoptosis of RGCs in the absence of growth factors with or without dexamethasone (1 microM) occurred in 68.5% +/- 3.4% and 53.4% +/- 2.6% of cells, respectively, after 96 hours. Addition of IL-10 at a concentration of 50 ng/mL significantly reduced the apoptotic population of RGCs to 28.2% +/- 2.3% in the absence of growth factors with dexamethasone and to 31% +/- 2.7% in the absence of growth factors alone. RGCs as well as native retina expressed functional IL-10R as determined by immunoblot analysis and by the ability of IL-10 to phosphorylate Stat-3. However, IL-10 failed to phosphorylate Akt in these cells. CONCLUSIONS: IL-10 caused a 59% and 42% reduction in the apoptotic population of serum-deprived cells with and without dexamethasone treatment, respectively. These observations establish that activation of IL-10R promotes survival of RGCs and this survival-promoting activity is due to IL-10 signaling through the Stat-3 pathway, which inhibits the cell death and not through the Akt cell survival pathway. 相似文献
69.
In October 2002, the Russian military used a mysterious "gas" to incapacitate Chechen rebels at a Moscow theater. Despite increased interest in the potential use of lethal chemical weapons in recent years, the medical community has paid little attention to the development of incapacitating, calmative, and "less than lethal" technologies. In this analysis, we review the events surrounding the use of a calmative "gas" during the Russian military action and discuss what is currently known about fentanyl derivatives, their aerosolization, and the rationale for their use as incapacitating agents. Collectively, the available evidence strongly suggests that a combination of a potent aerosolized fentanyl derivative, such as carfentanil, and an inhalational anesthetic, such as halothane, was used. The paper also assesses potential errors leading to the loss of a substantial number of hostages. Several lessons can be learned from this surprising and novel use of an incapacitating gas. 相似文献
70.
T cell subsets and sIL-2R/IL-2 levels in patients with glaucoma 总被引:12,自引:0,他引:12
PURPOSE: We hypothesize that cellular immunity may have a previously unrecognized role in glaucomatous optic neuropathy. The purpose of this study is to analyze subsets of T cells and the levels of cytokine IL-2 and the soluble IL-2 receptor in peripheral blood from patients with normal pressure glaucoma (NPG) or primary open angle glaucoma (POAG) in comparison to age-matched control subjects. METHODS: In this study, 38 patients (20 NPG; 18 POAG) and 19 controls were included. sIL-2R and IL-2 were assayed by ELISA. T cell subsets were analyzed by flow cytometry and lymphocyte proliferation was used to measure the reactive ability of T cells to phytohemagglutinin (PHA). RESULTS: The frequency of CD8(+)HLA-DR(+) lymphocytes were increased in patients with NPG (P = 0.008), and CD3(+)CD8(+) lymphocytes increased in both NPG (P = 0.03) and POAG patients (P = 0.0004). CD5(+) lymphocytes were higher only in POAG patients (P = 0.0012). In comparison to controls, the ratio of CD4(+)/CD8(+) lymphocytes was similar in both groups. The mean concentrations of sIL-2R in NPG (P = 0.011) and POAG (P = 0.0023) patients were higher than that found in control subjects although IL-2 concentrations were similar in these groups. In addition, the reactive ability of T lymphocytes to the non-specific reagent (PHA) was reduced significantly in NPG (P = 0.02) and POAG patients (P=0.04). CONCLUSION: The alterations of the cellular immune system in patients with glaucoma support our hypothesis that the immune system may play an important role in the initiation and/or sustainment of glaucomatous optic neuropathy in some patients. 相似文献