短期补充鱼油对超重高血压患者大动脉弹性的改善作用

该文探讨超重的高血压患者短期摄入富含n-3脂肪酸的鱼油对其动脉弹性的影响。方法：社区高血压患者52例（男41例，女11例）经洗脱期去除6例后，随机分为鱼油组（n=23，补充3g／d鱼油胶囊）和安慰剂组（n=20，试验过程中有3例被去除，补充3粒／d安慰剂）共8周。桡动脉脉搏波测定法测量大、小动脉弹性指数（C1和C2），测定空腹血清游离脂肪酸组成、血脂、血糖、胰岛素等。     

新发高血压病人游离脂肪酸与动脉弹性变化

目的 观察一个人群中新发高血压病人和未发生高血压者基线空腹血清游离脂肪酸(FFA)与2年内动脉弹性的变化的相关性,探索血清FFA、动脉弹性及高血压之间的关系.方法 一纵向研究.社区筛选128例健康非高血压者(年龄33～60岁),随访2年.记录新发高血压例数,采用CVProfilor DO-2020型动脉弹性功能测定仪检测两组2年前后大、小动脉弹性指数(C1和C2),测定基线空腹血FFA、血脂、血糖、胰岛素等.随访期间,有12人失访.结果 1)与未发生高血压者(n=97)相比,新发高血压病人(n=19)基线空腹血清饱和脂肪酸水平增高[(217±68)μmol/L比未发生高血压组:(186±46)μmol/L,P=0.04],而多不饱和与饱和脂肪酸比值(P/S)降低(1.60±0.37比未发生高血压组:1.90±0.46,P=0.009);2)与未发生高血压者相比,新发高血压者2年的收缩压和舒张压水平增高(P均＜0.01),而其大、小动脉弹性指数改变值(△C1和△C2)有降低趋势(P均＞0.05);3)逐步线性回归模型分析显示:全部参与者2年的△C1与基线空腹血清P/S正相关(标准回归系数0.201,P=0.041),独立于基线收缩压水平和经典的心血管危险因素.4)Logistic回归模型分析显示新发高血压者的基线空腹血清P/S的优势比(OR值)和95%可信区间为0.412(0.172～0.991,P=0.048)(在调整了经典的高血压危险因素后).结论 空腹血FFA组成异常是中青年非高血压人群大动脉弹性年龄相关改变和发生高血压的危险因素之一.     

新发高血压病人游离脂肪酸与动脉弹性变化

目的观察一个人群中新发高血压病人和未发生高血压者基线空腹血清游离脂肪酸(FFA)与2年内动脉弹性的变化的相关性,探索血清FFA、动脉弹性及高血压之间的关系。方法一纵向研究。社区筛选128例健康非高血压者(年龄33～60岁),随访2年。记录新发高血压例数,采用CVProfilorDO-2020型动脉弹性功能测定仪检测两组2年前后大、小动脉弹性指数(C1和C2),测定基线空腹血FFA、血脂、血糖、胰岛素等。随访期间,有12人失访。结果1)与未发生高血压者(n=97)相比,新发高血压病人(n=19)基线空腹血清饱和脂肪酸水平增高[(217±68)μmol/L比未发生高血压组:(186±46)μmol/L,P=0.04],而多不饱和与饱和脂肪酸比值(P/S)降低(1.60±0.37比未发生高血压组:1.90±0.46,P=0.009);2)与未发生高血压者相比,新发高血压者2年的收缩压和舒张压水平增高(P均<0.01),而其大、小动脉弹性指数改变值(ΔC1和ΔC2)有降低趋势(P均>0.05);3)逐步线性回归模型分析显示:全部参与者2年的ΔC1与基线空腹血清P/S正相关(标准回归系数0.201,P=0.041),独立于基线收缩压水平和经典的心血管危险因素。4)Logistic回归模型分析显示新发高血压者的基线空腹血清P/S的优势比(OR值)和95%可信区间为0.412(0.172～0.991,P=0.048)(在调整了经典的高血压危险因素后)。结论空腹血FFA组成异常是中青年非高血压人群大动脉弹性年龄相关改变和发生高血压的危险因素之一。     

中青年高血压病患者动脉弹性功能与血清脂肪酸

目的观察中青年高血压病患者和健康对照者基线空腹血清游离脂肪酸(FFA)的差异和大、小动脉弹性功能2年的变化。方法社区筛选高血压病患者103例(33～60岁),并筛选128例健康非高血压者(年龄匹配),随访2年。采用CVProfilorDO-2020型动脉弹性功能测定仪检测两组2年前后大、小动脉弹性指数(C1和C2),测定基线空腹血FFA、血脂、血糖、胰岛素等。高血压组91例,非高血压组97例得到随访。结果1)高血压病患者(n=91)的C1、C2均显著低于非高血压病患者[n=97;C1,11.9±3.9比非高血压组:(14.0±4.2)mL/mmHg×10,P=0.001;C2,4.9±2.2比非高血压病组:(6.1±2.6)mL/mmHg×100,P=0.001]。2)高血压病患者2年的小动脉弹性指数变化值(ΔC2)显著低于非高血压病患者[-0.24±0.25比非高血压组:(0.75±0.31)mL/mmHg×100,P=0.014],其大动脉弹性指数变化值(ΔC1)也降低,但差异无统计学意义(P=0.458)。3)与非高血压病患者相比,高血压病患者基线空腹血清饱和脂肪酸、单不饱和脂肪酸水平均显著增高(P均<0.05),而n-3脂肪酸水平[(96.0±38.9)比非高血压病组:(123.0±36.0)μmol/L,P=0.001]、多不饱和与饱和脂肪酸比值(P/S)(1.60±0.37比非高血压病组:1.90±0.46,P=0.009)显著降低。4)logistic回归分析显示高血压病患者基线空腹血清亚麻酸(18:3n3)优势比(OR值)和95%可信区间为2.483(1.480～4.166,P=0.001),而DHA(22:6n3)的为0.329(0.195～0.554,P=0.001)。结论原发性高血压患者动脉弹性年龄相关降低过程加速,空腹血清FFA组成异常(如亚麻酸增高,DHA下降),可能是其高血压发病的危险因素之一。     

中青年高血压病患者动脉弹性功能与血清脂肪酸

目的 观察中青年高血压病患者和健康对照者基线空腹血清游离脂肪酸(FFA)的差异和大、小动脉弹性功能2年的变化.方法 社区筛选高血压病患者103例(33～60岁),并筛选128例健康非高血压者(年龄匹配),随访2年.采用CVProfilor DO-2020型动脉弹性功能测定仪检测两组2年前后大、小动脉弹性指数(C1和C2),测定基线空腹血FFA、血脂、血糖、胰岛素等.高血压组91例,非高血压组97例得到随访.结果 1)高血压病患者(n=91)的C1、C2均显著低于非高血压病患者[n=97;C1,11.9±3.9比非高血压组:(14.0±4.2)mL/mm Hg×10,P=0.001;C2,4.9±2.2比非高血压病组:(6.1±2.6)mL/mm Hg×100,P=0.001].2)高血压病患者2年的小动脉弹性指数变化值(△C2)显著低于非高血压病患者[-0.24±0.25比非高血压组:(0.75±0.31)mL/mm Hg×100,P=0.014],其大动脉弹性指数变化值(△C1)也降低,但差异无统计学意义(P=0.458).3)与非高血压病患者相比,高血压病患者基线空腹血清饱和脂肪酸、单不饱和脂肪酸水平均显著增高(P均＜0.05),而n-3脂肪酸水平[(96.0±38.9)比非高血压病组:(123.0±36.0)μmol/L,P=0.001]、多不饱和与饱和脂肪酸比值(P/S)(1.60±0.37比非高血压病组:1.90±0.46,P=0.009)显著降低.4)logistic回归分析显示高血压病患者基线空腹血清亚麻酸(18:3 n3)优势比(OR值)和95%可信区间为2.483(1.480～4.166,P=0.001),而DHA(22:6 n3)的为0.329(0.195～0.554,P=0.001).结论 原发性高血压患者动脉弹性年龄相关降低过程加速,空腹血清FFA组成异常(如亚麻酸增高,DHA下降),可能是其高血压发病的危险因素之一.     

高脂及富含鱼油饮食对自发性高血压大鼠中心动脉弹性的影响

目的探讨高脂及富含鱼油饮食对自发性高血压(SH)大鼠中心动脉弹性的影响。方法 36只8周龄SH大鼠饲喂至14 w时,随机分为普通饮食组、高脂饮食组和高脂加鱼油组,每组12只,分别给予普通正常饲料、高脂饲料和高脂加鱼油饲料,分别饲喂至36 w。测定饮食干预前后大鼠血压,干预后血清游离脂肪酸(FFA)谱,应用彩色超声多普勒法测定中心动脉脉搏波传导速度(APWV),应用苏木精-伊红(HE)染色观察血管病理改变。结果喂养36 w后,高脂饮食组血压显著高于普食组和高脂加鱼油组(均P0.05);高脂饮食组饱和脂肪酸(SFA)高于普食组,n-3多不饱和脂肪酸(PUFA)、单不饱和脂肪酸(MUFA)低于普食组(均P0.05);而高脂加鱼油组大鼠SFA较高脂饮食组下降,MUFA和n-3PUFA显著上升(P0.05);彩色超声多普勒显示,高脂饮食组大鼠脉搏波导速度(APWV)显著高于普食组(P0.05),高脂加鱼油组低于高脂饮食组(P0.05);HE染色显示,高脂饮食组主动中膜横截面积(MCSA)增加,高脂加鱼油组MCSA较高脂饮食组下降(均P0.05)。结论长期给予高脂饮食能显著刺激SH大鼠大动脉血管壁改变,导致血管弹性功能降低,动脉僵硬度增加,而鱼油可逆转该病变,值得进一步深入研究。     

原发性高血压患者空腹血清游离脂肪酸组成的变化

目的 观察原发性高血压患者空腹血游离脂肪酸(free fatty acid,FFA)组成改变.方法 采用社区人群整群抽样、病例对照方法,筛选出高血压患者109例,其中肥胖患者70例,非肥胖患者39例,并以饮食习惯相近的123例血压正常个体(其中肥胖个体66例,非肥胖者57人)为对照,用高效液相色谱直接衍生化法检测空腹血清各种FFA浓度,放免法测定胰岛素水平.结果 (1)与血压正常个体比较,原发性高血压患者血清游离多不饱和脂肪酸(PUFA)水平降低(P=0.004),饱和脂肪酸(SFA)水平有增高趋势(P=0.06),P/S比值降低(P=0.000);血清PUFA中,n3 PUFA水平降低[(高血压组95.8±39.6 vs正常组122.0±33.4)μmol/L,P=0.000],n6 PUFA水平有降低趋势(P=0.124);前者主要是DHA水平(22:6n3)降低所致[分别为(高血压组64.7±39.2 vs正常组94.2±31.3)μmol/L,P=0.000],EPA(20:5n3)水平无明显变化,而α-亚麻酸水平(18:3n3)则升高(分别为高血压组21.2±7.2 vs正常组17.5±7.6)μmol/L,P=0.000],后者的亚油酸(18:2n6)水平有降低趋势(P=0.052)而AA(20:4n6)水平无明显变化.(2)与非高血压者相比较,原发性高血压患者C22:6/C20:5比值(n-3 △6去饱和酶活性指数)降低(P=0.002),C20:5/C18:3比值(n-3△5、△6去饱和酶活性指数)有降低趋势(P=0.065).(3)回归分析显示空腹血n-3 PUFA水平与舒张压水平独立负相关.结论 原发性高血压患者存在空腹血游离脂肪酸组成改变,表现为PUFA(主要是n3类)水平降低和P/S比值降低;这种改变提示α-亚麻酸向DHA的(22:6n3)生物转化缺陷与n-3 △6去饱和酶活性降低有关;这种改变与舒张压水平的升高独立相关.     

高脂饮食对自发性高血压大鼠中心动脉弹性的影响及鱼油的干预作用

目的观察高饱和脂肪酸及富含鱼油(n-3多不饱和脂肪酸)饮食对自发性高血压大鼠(SHR)大动脉弹性的影响。方法选择8周龄雄性SHR 30只,适应性喂养至14周龄后,按体重随机分为3组,每组10只,分别给予普通饲料、高脂饲料、高脂加鱼油饲料,持续喂养至36周龄,共干预22周。同龄对照大鼠(WKY)30只同前分组。干预后测定血压、体重、血浆游离脂肪酸谱、生化指标,喂养结束后,应用组织多普勒超声法测定中心动脉脉搏波传导速度(APWV),应用组织化学和免疫组织化学法测定中心动脉管壁的病理改变和基质金属蛋白酶9(MMP-9)的表达水平。结果 SHR高脂饮食组血压较普食组和高脂加鱼油组升高(160.5±5.5 mm Hg比153.1±1.0mm Hg、155.1±6.7 mm Hg,P0.01);HE染色显示高脂饮食组动脉管壁中膜横截面积(MCSA)较普食组增加(35500±8536μm2比28348±3956μm2,P0.05),高脂加鱼油组胸主动脉MCSA较高脂饮食组减小(16865±7235μm2,P0.05)。WKY大鼠MCSA无明显变化。SHR大鼠高脂饮食组主动脉弹力纤维占中膜面积百分比较普食组减少(21.1%±2.3%比30.7%±2.3%,P0.05),高脂加鱼油组较高脂饮食组升高(34.5%±4.1%,P0.05)。SHR大鼠高脂饮食组中心动脉APWV较普食组增加,而高脂加鱼油组APWV较高脂饮食组减小(P0.05)。SHR大鼠高脂饮食组的主动脉壁中MMP-9表达较普食组、高脂加鱼油组升高。结论高饱和脂肪酸饮食具有刺激SHR大鼠大动脉血管壁增厚、上调MMP-9在动脉壁表达及增加动脉僵硬度的作用,而富含n-3多不饱和脂肪酸的饮食可能通过逆转这一作用发挥预防及控制血压的作用。     

高血压患者空腹血游离脂肪酸组成与腰臀比、胰岛素活性的关系

目的 观察原发性高血压患者空腹血游离脂肪酸(free fatty acid,FFA)组成与向心性肥胖、胰岛素抗性、年龄、血清锌和饮食的关系及性别差异.方法 采用社区人群整群抽样、病例对照方法,筛选出高血压患者109例,其中肥胖患者70例,非肥胖患者39例,并以饮食习惯相近的123例血压正常个体(其中肥胖个体66例,非肥胖者57人)为对照,用高效液相色谱直接衍生化法检测空腹血清各种FFA浓度,放免法测定胰岛素水平.结果 (1)多元逐步线性回归和分层分析显示空腹血清FFA组成(包括n-3PUFA水平、P/S比值、C20:5/C18:3、C22:6/C20:5及C20:4/C18:2比值)存在年龄和性别差异,即小于45岁年龄组高血压患者的FFA改变显著性大与超过46岁年龄组,男性高血压患者的FFA改变显著性大于女性.(2)分层、相关及回归分析显示空腹血清FFA组成与腰臀围比值、胰岛素敏感指数、血清锌水平、饮食习惯相关(均P＜0.05).(3)原发性高血压患者血清锌水平略低于非高血压个体(14.9±5.0 vs非高血压组16.8± 6.4)μmol/L,P=0.45.结论 原发性高血压患者空腹血游离脂肪酸组成改变与向心性肥胖、胰岛素抵抗、锌缺乏、年龄和饮食有关,并存在性别差异.     

氟伐他汀改善高血压患者脉压和动脉弹性临床研究

目的　观察氟伐他汀对降压治疗中高血压患者脉压和动脉弹性功能的影响。方法　选择 3 0例正在规律服用降压药物治疗并且脉压≥ 60mmHg的高血压患者 ,分为安慰剂组 (15例 )和氟伐他汀组 (15例 ) ,分别加服安慰剂 (1片每天 )或氟伐他汀 (40mg/d) ,治疗 3个月。观察治疗前、后肱动脉血压 ,脉搏波传导速度 (PWV) ,大动脉和小动脉弹性指数 (C1和C2 ) ,从桡动脉压力波形实时获得的中心动脉血压、压力反射波增强指数 (AI)。结果　安慰组治疗后各项指标均无显著改变。氟伐他汀组治疗后肱动脉收缩压与脉压分别降低 8 0± 12 9mmHg (P =0 0 3 1)与 5 7± 9 3mmHg (P =0 0 3 3 ) ,中心动脉收缩压与脉压分别降低 9 7± 12 4mmHg (P =0 0 0 9)与 7 1± 9 3mmHg (P =0 0 1) ,中心动脉下降幅度大于肱动脉 ;舒张压和心率无显著改变 ;C2 升高 (P =0 0 3 ) ;AI降低 (P =0 0 2 6) ;PWV和C1无显著改变。结论　氟伐他汀通过改善高血压患者小动脉弹性和外周压力波反射 ,具有缩小脉压的作用     

The immunoneuroendocrine role of melatonin

Abstract: A tight, physiological link between the pineal gland and the immune system is emerging from a series of experimental studies. This link might reflect the evolutionary connection between self-recognition and reproduction. Pinealectomy or other experimental methods which inhibit melatonin synthesis and secretion induce a state of immunodepression which is counteracted by melatonin. In general, melatonin seems to have an immunoenhancing effect that is particularly apparent in immunodepressive states. The negative effect of acute stress or immunosuppressive pharmacological treatments on various immune parameters are counteracted by melatonin. It seems important to note that one of the main targets of melatonin is the thymus, i.e., the central organ of the immune system. The clinical use of melatonin as an immunotherapeutic agent seems promising in primary and secondary immunodeficiencies as well as in cancer immunotherapy. The immunoenhancing action of melatonin seems to be mediated by T-helper cell-derived opioid peptides as well as by lymphokines and, perhaps, by pituitary hormones. Melatonin-induced-immuno-opioids (MHO) and lymphokines imply the presence of specific binding sites or melatonin receptors on cells of the immune system. On the other hand, lymphokines such as -γ-interferon and interleukin-2 as well as thymic hormones can modulate the synthesis of melatonin in the pineal gland. The pineal gland might thus be viewed as the crux of a sophisticated immunoneuroendocrine network which functions as an unconscious, diffuse sensory organ.     

Changes in connexin43, the gap junction protein of astrocytes, during development of the rat pineal gland

Abstract: The abundance of gap junctions between rat pineal astrocytes formed by connexin43 (Cx43) was studied during development. Levels and distribution of Cx43 were measured by immunoblotting and indirect immunofluorescence, respectively. The amount of Cx43 in cells located within the gland was low until about the 7th postnatal day and increased to adult values between the 14th and 21st days postpartum. Although astrocytes, recognized by their vimentin immunoreactivity, were scarce before birth, they were abundant by the 7th postnatal day suggesting that the low levels of Cx43 found at this age corresponded to a low expression of this protein. Localization of the immunoreactivity to Cx43 and vimentin showed a close correlation, indicating that mature or immature pineal astrocytes form gap junctions made of Cx43. Since Cx43 levels attained their adult values at about the time the innervation and the functional state of the gland reached maturity (2–3 weeks after birth), it is proposed that astrocyte gap junctions are involved in the function of the adult rat pineal gland.     

Conservative management of perforated duodenal diverticulum： A case report and review of the literature

Duodenal diverticula are a relatively common condition. They are asymptomatic, unless they become complicated, with perforation being the rarest but most severe complication. Surgical treatment is the most frequently performed approach. We report the case of a patient with a perforated duodenal diverticulum, which was diagnosed early and treated conservatively with antibiotics and percutaneous drainage of secondary retroperitoneal abscesses. We suggest this method could be an acceptable option for the management of similar cases, provided that the patient is in good general condition and without septic signs.     

Response of rat pineal melatonin to calcium, magnesium, and lithium is circadian stage dependent

Abstract: Herein we documented the response of pineal melatonin production to electrolytes known to be effective on pineal function in view of a possible circadian stage dependence. We studied the release of melatonin by perifused rat pineal glands at 2 different circadian stages corresponding to the middle of the light and dark periods, i.e., respectively, 7 and 19 HALO (Hours After Light Onset, L:D = 12:12). The initial efflux rates were, as expected, much higher in the perifusates of glands removed from rats sacrificed during the dark phase than of those removed during the light phase. After 3 hr of perifusion, melatonin release reached similar levels which were found constant up to the 8th hr of perifusion, whatever the circadian stage. Perifusion of the glands with physiological concentrations for the rat of calcium (5.2 mmol/1) and magnesium (1.34 mmol/1) resulted in a stimulatory effect on the pineal glands removed from rats sacrificed in the middle of the dark period (19 HALO), whereas no effects were observed on the pineal glands removed from rats sacrificed during the light (7 HALO). Lithium (0.28 and 0.55 mmol/1) was ineffective on melatonin release in pineal glands removed 7 and 19 HALO. Our results show differences in the initial efflux rates of melatonin and in the response of perifused pineal glands to calcium and magnesium according to the circadian stage.     

Presence of immunoreactive growth hormone and prolactin in the ovine pineal gland

Abstract: The use of antisera raised against bovine growth hormone (GH) and ovine prolactin (PRL) enabled the detection of related immunoreactive (ir) sequences of proteins in ovine pineal tissue. The isolation of PRL-like ir-material was accomplished using a 0.25 M ammonium sulphate (pH 5.5) extraction followed by ethanol precipitation, whereas the resulting 2.0 M ammonium sulphate (pH 7.0) precipitate contained a GH-like immunoreactivity. Gel chromatography of the GH-like immunoreactivity (Sephadex G-100) indicated the presence of several GH-like fragments ranging in the M_r range of 7,000 to 55,000. Analyses of the PRL-like ir-material found in pineal tissue on HPLC using a TSK 545-DEAE column led to the resolution into a single peak of immunoreactivity. A single peak of activity was also observed following chromatofocusing and hydrophobic interaction chromatography of the ir-peak from the TSK 545-DEAE column. The PRL-like ir-material inhibited the binding of [¹²⁵I]ovine PRL-S14 to anti-ovine PRL antibodies without showing an affinity for binding to anti-rat PRL or anti-bovine GH antibodies. Scatchard analysis of the binding of pineal PRL-like ir-material and pituitary ovine PRL-S14 to liver membranes from day-20 pregnant rats revealed similar affinity constants (K_a of 4.7 ± 0.2 × 10⁹ M^-1). In addition, the replication of Nb 2 Node rat lymphoma cells was stimulated by pineal PRL-like ir-material, an effect known to be specific for lactogenic hormones. The pineal PRL-like immunoreactivity appeared on sodium dodecyl sulfate polyacrylamide gels as a single major band of M_r 24,000. The functional status of PRL-and GH-like ir-material in the ovine pineal remains to be determined, but evidence is presented that the overall protein synthesis rate of the rat pineal responded to circulating concentrations of PRL.     

Microbiology of human immunodeficiency virus anorectal disease

PURPOSE: Individuals who are seropositive for the human immunodeficiency virus are at high risk for opportunistic infection and anorectal disorders. Little prospective information is available regarding anorectal pathogens in these patients. METHODS: One hundred sixty-three HIV-seropositive patients presented to the colorectal clinic between 1989 and 1992. Forty-seven (29 percent) patients were thought to have an infectious process and were prospectively studied using a standardized multiculture protocol. RESULTS: Mean age was 33 (range, 19–59) years. All were male; high-risk behavior accounted for 87 percent of HIV transmissions. Presenting complaints included anorectal pain (79 percent), pus per anum (28 percent), and blood per anum (26 percent). Examination revealed perianal tenderness (60 percent), condyloma (38 percent), perianal ulcers (38 percent), and anal fissures (34 percent). Sixty-six sets of cultures were performed; 28 patients had one set, 15 had two sets, and 4 had three sets. Thirty-two of these 47 patients (68 percent) had positive cultures including herpes (50 percent), cytomegalovirus (25 percent),Neisseria gonorrhoeae (16 percent), chlamydia (16 percent), acidfast bacilli (2 percent), and others (9 percent). Six of 32 patients with positive cultures had more than one organism cultured. Sixteen (50 percent) patients with positive cultures were treated medically, 8 (25 percent) were treated surgically and 8 (25 percent) were treated with both modalities. Sixty-one procedures were performed on 17 patients for condylomata. Eighteen patients had 20 procedures for abscesses, 50 percent of whom had positive cultures for other than common bowel flora; all improved. Fourteen patients underwent 33 procedures for perianal fistulas.Mycobacterium fortuitum was cultured from one patient who required 13 procedures for abscesses and fistulas. Forty-five (96 percent) patients were followed for an average of 12.5 months ±2.9 SEM (range, 1–94 months). Symptoms were improved or resolved in 22 of 32 (69 percent) patients with positive cultures and in 11 of 13 (84 percent) with negative cultures. CONCLUSIONS: Specific pathogens may often be identified in human immunodeficiency virus-seropositive patients with anorectal disorders if aggressively sought. Although patients without specific pathogens identified may be expected to improve with planned empiric treatment, positive identification allows more directed therapy.