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21.
Ganesan Sathiyanarayanan Ganesan Saibaba George Seghal Kiran 《Critical reviews in microbiology》2017,43(3):294-312
Marine sponges are filter feeding porous animals and usually harbor a remarkable array of microorganisms in their mesohyl tissues as transient and resident endosymbionts. The marine sponge-microbial interactions are highly complex and, in some cases, the relationships are thought to be truly symbiotic or mutualistic rather than temporary associations resulting from sponge filter-feeding activity. The marine sponge-associated bacteria are fascinating source for various biomolecules that are of potential interest to several biotechnological industries. In recent times, a particular attention has been devoted to bacterial biopolymer (polyesters) such as intracellular polyhydroxyalkanoates (PHAs) produced by sponge-associated bacteria. Bacterial PHAs act as an internal reserve for carbon and energy and also are a tremendous alternative for fossil fuel-based polymers mainly due to their eco-friendliness. In addition, PHAs are produced when the microorganisms are under stressful conditions and this biopolymer synthesis might be exhibited as one of the survival mechanisms of sponge-associated or endosymbiotic bacteria which exist in a highly competitive and stressful sponge-mesohyl microenvironment. In this review, we have emphasized the industrial prospects of marine bacteria for the commercial production of PHAs and special importance has been given to marine sponge-associated bacteria as a potential resource for PHAs. 相似文献
22.
Rationale:Medullary sponge kidney (MSK) is a congenital renal disorder characterized by recurrent nephrolithiasis or nephrocalcinosis. Recently, it has been found that MSK can be also combined with other diseases, such as primary aldosteronism and Beckwith-Wiedemann, but whether it is associated with secondary hypertension remains unknown.Patient concerns:A 22-year-old hypertensive female presented to our hospital characterized by hypokalemia and hypertension.Diagnosis:The laboratory examination showed secondary aldosteronism. And the common causes for secondary aldosteronism include renal artery stenosis, glomerulonephritis, lupus nephropathy, and diabetic nephropathy, all of which were excluded except MSK.Interventions:She was treated with angiotensin-converting enzyme inhibitors.Outcomes:Her blood pressure, serum potassium, and plasma renin levels were reversed after treatment with angiotensin-converting enzyme inhibitors.Lessons:We presumed that MSK may be associated with secondary hypertension, and the mechanism may be the activation of the renin-angiotensin-aldosterone system. 相似文献
23.
目的 建立兔腰椎板开窗术后微小骨粒回植模型,为临床提供实验依据。方法 将18只雄性新西兰兔,分为两组。对照组在全麻后以L5棘突为中心,充分显露左侧L5椎板,用微型小枪钳慢慢咬去椎板、黄韧带,进行开窗术,暴露约0.8 x 0.3 cm大小骨窗后直接缝合处理。实验组在L5左侧开窗后将开窗咬下的碎骨粒剪碎,然后将碎骨粒镶嵌于医用胶原蛋白海绵,塑成拱桥形,放置于硬膜外开窗处,缝合切口,术后观察椎板开窗位置CT及组织学变化。结果 CT检查示术后8周实验组开窗处微小骨粒形成菲薄的骨板,12周后形成的骨板较厚,骨梁连续,椎管形态及容积无明显变化,未见脊髓受压。对照组开窗处在8、12周局部有少量骨质增生,周围黏连组织侵入椎管,椎管未重建。结论 兔椎板开窗处再植自体微小骨粒的骨重建,形成的骨板可遮挡疤痕侵入椎管,减少椎管内黏连。 相似文献
24.
《Journal of biomaterials science. Polymer edition》2013,24(9):957-968
Vascularization into a poly(vinyl alcohol) (PVA) sponge was investigated using basic fibroblast growth factor (bFGF). This growth factor was impregnated into biodegradable gelatin microspheres for its sustained release and then the bFGF-containing microspheres or free bFGF were incorporated into PVA sponges. Following subcutaneous implantation into the back of mice, the bFGF-containing gelatin microspheres induced vascularization in and around the sponge to a significantly greater extent than that of free bFGF from 3 days after implantation. Significant ingrowth of fibrous tissue into the sponge was also observed when bFGF-containing microspheres were added to the sponge in contrast to free bFGF. Tissue ingrowth occurred into the deeper portion of the sponge over time while it accompanied formation of new capillaries. Empty gelatin microspheres had no effect on vascularization and the level of fibrous tissue ingrowth into the sponge was similar to that of the control group. It was concluded that incorporation of gelatin microspheres containing bFGF into the PVA sponge was effective in prevascularization of the sponge pores. 相似文献
25.
26.
目的分析比较高分子止血海绵和鼻腔止血器在鼻内镜术后的止血效果。方法选取100例需要进行鼻腔、鼻窦手术患者,其中男性76例,女性24例;年龄18~60岁,中位年龄36岁。随机分为2组,试验组50例,对照组50例。在术后分别放置高分子止血海绵和鼻腔止血器,观察患者的疼痛反应和止血效果,并对比取出填塞物时的难易程度及出血量,进行对比分析。结果两者止血效果相当,试验组少量渗血36例,对照组29例;两组无出血病例;止血效果两组差异无统计学意义(P0.05)。试验组无痛、轻度疼痛各26、24例,对照组各3、44例。试验组填塞物容易取出46例,对照组21例。两组在鼻腔胀痛、头痛、抽出时难易程度、抽出时出血量方面的差异均有统计学意义(P0.05),均显示试验组的效果优于对照组。结论鼻腔止血器不良反应少,临床效果优于高分子止血海绵填塞,值得广泛推广。 相似文献
27.
目的:总结斯泰可(stypro)可吸收止血胶原海绵在心脏外科手术中的使用体会。方法:回顾性分析我科心脏手术患者300例,以使用不同止血材料平均分为三组,每组各100例。骨蜡组以骨蜡完成胸骨断面止血;斯泰可组和明胶海绵组钝性去除填塞于胸骨骨髓腔中的骨蜡,代之以剪裁成适合宽度的斯泰可(stypro)可吸收止血胶原海绵或明胶海绵填充后关闭胸骨。分析比较三组术后24h纵膈引流量,术后胸骨哆开情况,伤口脂肪液化或感染情况,二次开胸止血以及骨蜡排异情况。结果:三组引流量斯泰可组明显少于其他两组[(153.5±50.5)vs.(250.5±102.5)vs.(332.5±105.5)mL,P0.05];术后拔除气管插管时间、术后平均住院天数、胸骨哆开、伤口脂肪液化或感染、二次开胸止血以及骨蜡排异例数,斯泰可组明显优于其他两组。结论:斯泰可(stypro)止血胶原海绵在心脏外科术中胸骨断面止血效果明确,应用简便,建议临床推广应用。 相似文献
28.
目的:探讨在下颌阻生牙拔除术后应用胶原蛋白海绵的临床效果。方法:选取2016年11月—2017年11月在天津市口腔医院行下颌阻生牙拔除术的患者150例,随机分为常规组和胶原蛋白海绵组。胶原蛋白海绵组患者进行下颌阻生牙拔除术后在拔牙窝内填入胶原蛋白海绵,常规组患者则只进行常规拔牙处置,比较2组患者拔牙后的相关情况。采用SPSS 20.0软件包对数据进行统计学处理。结果:胶原蛋白海绵组患者拔牙后30 min内拔牙窝出血率显著低于常规组(P<0.05),拔牙后第1天和第3天疼痛程度评分显著低于常规组(P<0.05),拔牙后干槽症和其他并发症的发生率显著低于常规组(P<0.05)。结论:在下颌阻生牙拔除术后应用胶原蛋白海绵,不仅可以有效减少术后出血量,而且可以有效降低术后干槽症和其他并发症的发生率,值得推广应用。 相似文献
29.
目的:观察Gelatamp胶质银明胶海绵在前牙区Ⅱ型种植位点的临床应用效果。方法:选择40例前牙区拔牙拟作Ⅱ型种植的病人,随机分层分为Gelatamp胶质银明胶海绵填塞止血组(试验组)及棉球压迫止血组(对照组)。拔牙后,试验组在牙槽窝置入Gelatamp胶质银明胶海绵,对照组常规紧咬棉球30分钟后取出,观察比较两组的止血效果和4周后行Ⅱ型种植手术前拔牙位点软组织愈合的情况。结果:试验组拔牙创出血很快停止,出血平均时间为0.67分,试验组、对照组止血效果有效率分别为100%,80%,差异有统计学意义(P<0.05)。在4周后Ⅱ型种植手术前试验组、对照组的软组织愈合良好率分别为70%和40%,差异有统计学意义(P<0.05)。结论:Gelatamp胶质银明胶海绵,能显著缩短出血时间,有效增强止血效果,具有止血和持久杀菌的双重效果,有利于形成良好的软组织,有利于早期种植体植入后封闭创面,具有一定的临床应用价值。 相似文献
30.
Peter D. Mariner Justin M. Wudel David E. Miller E. Erin Genova Sven‐Olrik Streubel Kristi S. Anseth 《Journal of orthopaedic research》2013,31(3):401-406
Medtronic's INFUSE Bone Graft provides surgeons with a potent tool for stimulating bone formation. Current delivery vehicles that rely on Absorbable Collagen Sponges (ACS) require excessive quantities of the active ingredient in INFUSE, recombinant human Bone Morphogenic Protein‐2 (rhBMP2), to achieve physiologically relevant concentrations of the growth factor, driving up the cost of the product and increasing the likelihood of undesirable side effects in neighboring tissues. We demonstrate that a simple light‐mediated, thiol‐ene chemistry can be used to create an effective polymer delivery vehicle for rhBMP2, eliminating the use of xenographic materials and reducing the dose of rhBMP2 required to achieve therapeutic effects. Comprised entirely of synthetic components, this system entraps rhBMP2 within a biocompatible hydrogel scaffold that is degraded by naturally occurring remodeling enzymes, clearing the way for new tissue formation. When tested side‐by‐side with ACS in a critical‐sized bone defect model in rats, this polymeric delivery system significantly increased bone formation over ACS controls. © 2012 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 31: 401–406, 2013 相似文献