1,25 二羟基维生素D3 对兔角膜碱烧伤朗格罕氏细胞影响

目的:研究1,25二羟基维生素D3(骨化三醇)对兔角膜碱烧伤后角膜朗格罕氏细胞分布的影响,并初步探讨其作用机制。方法:在兔角膜制作碱烧伤模型,然后实验组局部和全身给予1,25二羟基维生素D3,分别在第3,7,21天时对正常组,实验组和对照组家兔行角膜共聚焦显微镜,HE染色观察角膜病理改变。结果:正常组角膜中央在三个时间点均未检测出朗格罕氏细胞。实验组和对照组碱烧伤后3、7天角膜中央出现朗格罕氏细胞,对照组密度高于实验组(p<0.05);碱烧伤后21天两组朗格罕氏细胞密度相近(p>0.05)。实验组炎性反应程度在第7,21天时轻于对照组。结论:1,25二羟基维生素D3能够在兔角膜碱烧伤早期抑制朗格罕氏细胞的向心性迁移,并且能在一定程度上抑制炎性反应。     

表皮生长因子治疗兔角膜碱烧伤研究

本试验制成兔角膜碱烧伤模型,应用重组表皮生长因子（ｒｈＥＧＦ）滴眼剂对碱烧伤后的兔角膜溃疡创面进行治疗。６３只纯种新西兰白兔分为７组,每组９只,其中５组为治疗组,另２组为对照组,治疗组分别用每毫升０．５,５,２０,５０和１００μｇ表皮生长因子滴眼剂滴眼,对照组分别用纤维结合蛋白和氯霉素滴眼。伤后２４,４８,７２,９６及１２０ｈ裂隙灯荧光素染色,照像观察溃疡面积,经计算机图像处理,计算。结果显示５组治疗组创面愈合时间明显短于对照组,（Ｐ＜０．０５）。提示ＥＧＦ对角膜碱烧伤后的溃疡面愈合有促进作用。     

1,25二羟基维生素D_3对兔角膜碱烧伤朗格罕氏细胞影响

目的：研究1,25二羟基维生素D3（骨化三醇）对兔角膜碱烧伤后角膜朗格罕氏细胞分布的影响,并初步探讨其作用机制。方法：在兔角膜制作碱烧伤模型,然后实验组局部和全身给予1,25二羟基维生素D3,分别在第3,7,21天时对正常组,实验组和对照组家兔行角膜共聚焦显微镜,HE染色观察角膜病理改变。结果：正常组角膜中央在三个时间点均未检测出朗格罕氏细胞。实验组和对照组碱烧伤后3、7天角膜中央出现朗格罕氏细胞,对照组密度高于实验组（p〈0.05）;碱烧伤后21天两组朗格罕氏细胞密度相近（p〉0.05）。实验组炎性反应程度在第7,21天时轻于对照组。结论：1,25二羟基维生素D3能够在兔角膜碱烧伤早期抑制朗格罕氏细胞的向心性迁移,并且能在一定程度上抑制炎性反应。     

HIF-1α在大鼠造影剂肾病中的表达及对肾小管损伤的影响

目的:探讨HIF-1α在造影剂肾病大鼠血清中的表达水平及对肾小管损伤的影响。方法:将45只SD大鼠随机分为三组,每组15只。其中空白对照组(A组)大鼠禁食水12 h后,于尾静脉注射氯化钠注射液0.5 m L,共三次,每次间隔15 min。造影剂肾病组(B组)大鼠禁食水12 h后,于尾静脉以10 mg/kg注射吲哚美辛,15 min后以10 mg/kg注射左旋硝基精氨酸甲酯(L-NAME),15 min后再注射碘比醇(3 g I/kg)。阿托伐他汀钙组(C组)大鼠于实验前3 d开始喂食阿托伐他汀钙片,连续喂食3天,剂量为80mg/kg/d,再禁食水12 h后,制作造影剂肾病模型,步骤同造影剂肾病组。观察并比较三组大鼠肾功能指标(BUN、Cr)变化、HIF-1α表达水平及肾小管损伤情况。结果:造影剂肾病组大鼠BUN水平低于阿托伐他汀钙组和空白对照组,而Scr水平高于阿托伐他汀钙组和空白对照组,差异均具有统计学意义(P0.05)。阿托伐他汀钙组大鼠BUN水平低于空白对照组,而Scr水平高于空白对照组,差异具有统计学意义(P0.05)。造影剂肾病组大鼠肾小管损伤高于阿托伐他汀钙组和空白对照组,阿托伐他汀钙组大鼠肾小管损伤高于空白对照组,差异均具有统计学意义(P0.05)。造影剂肾病组大鼠HIF-1α表达高于阿托伐他汀钙组和空白对照组,阿托伐他汀钙组大鼠HIF-1α表达高于空白对照组,差异均具有统计学意义(P0.05)。结论:造影剂肾病发生时存在缺氧情况,阿托伐他汀钙在造影剂肾病中具有保护作用。     

大鼠咬合创伤牙周膜中MCP-1、ICAM-1的表达变化

目的:研究咬合创伤大鼠牙周组织中MCP-1、ICAM-1的表达情况。方法:12周龄雄性SD大鼠24只,随机分为4组(1个正常对照组和3个实验组),每组6只。正常对照组不作任何处理,实验组通过在大鼠左上颌第一磨牙颌面粘接树脂并内置不锈钢丝形成高出颌面0.6-0.8 mm的树脂层以建立同侧下颌咬合创伤实验动物模型,分别于建模后3、5、7 d处死各组大鼠,分离大鼠下颌组织,运用HE、Masson染色观察咬合创伤牙周组织形态变化,同时用免疫组织化学染色法检测MCP-1和ICAM-1的表达变化。结果:HE染色显示,正常组牙周膜纤维排列整齐,牙骨质表面较为平整,牙槽骨结构致密。实验组牙周膜纤维排列紊乱,牙周膜血管水肿充血、间隙改变,牙槽骨和牙骨质表面不平整,出现骨吸收。Masson染色显示,正常组牙周组织未见异常表现;实验组牙周膜纤维排列紊乱,可见水解断裂,局部有血流障碍和血管破裂。免疫组织化学显示,各实验组MCP-1和ICAM-1的表达变化均较正常对照组增多,差异有显著性(P0.05)。其中7 d组表达水平最高,与其他2组相比有统计学意义(P0.05)。结论:咬合创伤可引起大鼠牙周组织形态变化,MCP-1、ICAM-1的表达随时间呈现递增的趋势。     

辣椒素预防大鼠胃缺血再灌注损伤的作用及机制研究

本研究为探讨辣椒素(CAP)对大鼠胃缺血再灌注损伤(GI-R)的作用及机制。成年雄性健康SD大鼠40只,随机分为4组,每组10只,A组(空白对照组),B组(手术组),C组(CAP组),D组(CAP+手术组)。给予A组、B组大鼠灌胃生理盐水10 m L/kg/d,C组、D组大鼠灌胃CAP1 mg/kg/d。4周后B组、D组于GI-R模型建立后24小时处死大鼠,收集胃液测定胃酸总酸度,肉眼计数胃黏膜损伤指数,行胃窦组织病理学观察,检测胃黏膜辣椒素受体(TRPV1)、降钙素基因相关肽(CGRP)的表达,检测胃窦组织丙二醛(MDA)、超氧化物歧化酶(SOD)的水平。结果显示A组、C组胃黏膜未见损伤;与B组相比,D组胃黏膜损伤程度显著减轻(P0.05),胃酸总酸度显著降低(P0.05),MDA值显著降低(P0.05),SOD值显著升高(P0.05),TRPV1、CGRP表达显著增多(P0.05)。实验结果表明预先给予CAP 1 mg/kg/d连续灌胃4周具有预防缺血再灌注致大鼠胃黏膜损伤的作用,其机制可能与CAP上调TRPV1、CGRP在胃内的表达、减轻氧自由基损伤有关。     

大鼠实验性流产模型的建立及黄芪多糖对其的影响

目的应用细菌脂多糖(Lipopolysaccharides,LPS)尾静脉注射建立大鼠实验性流产动物模型,研究黄芪多糖(astragalus polysacharin,APS)对实验性流产大鼠保胎的作用。方法采用怀孕第7天Sprague-Dawley(SD)大鼠尾静脉注射LPS每只1.0μg,建立实验性大鼠流产模型,以正常怀孕大鼠尾静脉注射磷酸缓冲液(PBS)每只1.0mL作为对照组,随机将模型组大鼠分为流产模型组、APS组。APS组于怀孕4～9d口服APS2mL(150mg)/d,对照组与和流产模型组分别于4～9d口服生理盐水2mL/d。于实验第10天麻醉处死各组大鼠,计数妊娠成功比例和流产比例。结果 LPS诱导大鼠流产模型组流产比例高达8/11,而对照组和APS组流产比例分别为1/12和1/6,与流产模型组比较差异极显著(P0.01)。结论 LPS可以诱导建立大鼠流产模型,中药成分APS对实验性大鼠流产具有一定的保护作用。     

PD-L1 Ig在缓解肾移植急性排斥反应中的免疫调节作用

目的:探讨PD-L1 Ig(Programmed death ligand-1 immunoglobulin,程序性死亡配体-1免疫球蛋白)在缓解肾移植急性排斥反应中的免疫调节作用。方法:选择健康成年雄性Lewis大鼠24只作为供体,另取24只健康雄性Wistar大鼠作为受体。所选大鼠3个月龄,体重300 g±30 g,创建肾移植大鼠模型,并将其随机分为三组,空白对照组,对照组,和PD-L1 Ig组。空白对照组:灌注液,肾动脉灌注3分钟。PD-L1 Ig组:含1 m L的PD-L1 Ig的灌注液,肾动脉灌注3分钟。对照组不进行额外灌注操作。术后观察三组大鼠食欲、精神状态及生存情况。7天后取血标本观察肌酐、尿素氮、γ-干扰素(Interferon-γ, IFN-γ),白细胞介素-2(Interleukin-2, IL-2),白细胞介素-10 (Interleukin-10, IL-10)水平,同时三组各处死3只大鼠行肾脏病理学检查。结果:1.病理:对照组及空白对照组大鼠较模型大鼠有改善,仍有较多的炎细胞浸润,间质水肿,红细胞管型,肾小管上皮细胞脱落。而PD-L1 Ig组大鼠较模型大鼠、对照组及空白对照组有显著改善。2.生存状态和肾功能:PD-L1 Ig组大鼠生存时间最长50天,平均存活时间和体重均显著高于对照组和空白对照组,差异均有统计学意义(P0.05);血肌酐、尿素氮水平显著低于对照组和空白对照组,差异均有统计学意义(P0.05)。3.细胞因子变化:PD-L1 Ig组IFN-γ、IL-2水平显著低于空白对照组、对照组,差异均有统计学意义(P0.05);PD-L1 Ig组IL-10水平显著高于空白对照组、对照组,差异均有统计学意义(P0.05)。结论:PD-L1 Ig可降低IL-2和IFN-γ,提升IL-10,调节移植肾急性排斥反应的细胞因子平衡,改善肾功能,延长移植肾存活时间。     

乳源性复合益生菌对2型糖尿病大鼠GLP 1的影响及调控机制

目的观察乳源性复合益生菌对2型糖尿病大鼠胰高血糖素样肽-1(glucagon like peptide-1,GLP-1)的影响,并探讨其调控机制。方法采用高脂高糖饲养合并腹腔注射链脲佐菌素(Streptozotocin,STZ, 35 mg/kg)建立糖尿病大鼠模型(T2DM)。造模成功大鼠随机分为二甲双胍组(200 mg/kg)、低剂量复合益生菌组(1×10~8 CFU/d乳酸菌+1×10~6 CFU/d酵母菌)和高剂量复合益生菌组(1×10~(10) CFU/d乳酸菌+1×10~8 CFU/d酵母菌),以同周龄正常大鼠为正常对照组,灌胃4周。尾静脉采血测定空腹血糖、口服葡萄糖耐量;酶联免疫吸附法(ELISA)检测血清GLP-1和肽YY(PYY)水平;蛋白免疫印迹法(Western blot)检测结肠组织GLP-1蛋白表达;荧光定量PCR检测肠道菌群、G蛋白偶联受体(GPR43、GPR41)水平;气相色谱(GC)检测肠道短链脂肪酸(short chain fatty acids,SCFAs)含量。结果与模型组相比,高剂量复合益生菌能降低大鼠空腹血糖和口服糖耐量,增加肠道乳杆菌、双歧杆菌含量,提高肠道SCFAs含量,上调GPR43和GPR41 mRNA表达,促进胃肠激素GLP-1、PYY分泌,差异有统计学意义(均P0.05)。结论乳源性复合益生菌可显著促进T2D大鼠GLP-1的分泌,调节糖代谢,推测与调节肠道菌群-SCFAs-G蛋白偶联受体信号通路有关。     

咪喹莫特调节Th1、Th2细胞相关趋化因子表达抑制兔耳瘢痕增生

目的:免疫因素在增生性瘢痕的发生中起重要作用,本实验研究免疫抑制剂咪喹莫特对兔耳增生性瘢痕组织中辅助性T淋巴(Th)细胞亚群Th1、Th2细胞相关趋化因子CXCL10、CXCL12、CCL2、CCL3、CCL5、CCL7、CCL13表达的影响,探讨咪喹莫特抑制兔耳瘢痕增生的作用机制。方法:选取16只新西兰大耳白兔,雌雄不限。建立兔耳增生性瘢痕模型,每只兔耳腹侧做四个直径为1 cm的圆形创面,每个相距1.5 cm,双侧对称,右耳为咪喹莫特组涂抹5%咪喹莫特软膏,左耳为空白对照组涂抹等量凡士林软膏,待术后14天上皮化均完全后开始涂抹,一日一次,持续一个月。分别于术后第21、28、35、42、49、56、63天同一时间空气栓塞法随机处死2只兔子,收集所有瘢痕标本。另外处死2只健康兔并采集兔耳正常皮肤组织。所有标本行HE染色及Masson三色法染色,观察形态学差异;测量并计算瘢痕增生指数(Scar elevation index,SEI);行Real-time PCR检测CXCL10、CXCL12、CCL2、CCL3、CCL5、CCL7、CCL13的表达。结果:HE及Masson染色可见咪喹莫特组胶原沉积较空白对照组明显减少,SEI显示空白对照组于术后第28天增生程度达到高峰,其增生程度明显高于咪喹莫特组(P0.05);Real-time PCR结果可见咪喹莫特组Th2细胞相关趋化因子CCL2、CCL3、CCL5、CCL7及CCL13表达在各时间点较空白对照组明显降低,Th1细胞相关趋化因子CXCL10、CXCL12的表达在各时间点较空白对照组明显增高(P0.05)。结论:咪喹莫特可通过调节Th1、Th2细胞相关趋化因子的表达来发挥抑制兔耳瘢痕增生的作用。     

Morphological and cytological characteristics of the burn healing process by various treatment methods

Morphological and cytological methods were used to study the healing of a burn wound in local isolation wards (an open treatment method) and under ointment bandages (a closed treatment method). Biopsy specimens and imprints from the burn wound surface were taken from 40 patients. During treatment in an abacterial medium, burn wound was rapidly decontaminated, which was a consequence of the appearance in wound exudate of segmented neutrophils with marked neutrophilic granularity. Granulation tissue was formed in the wound cavity at the 5th-7th day after the treatment commencement. During treatment under bandages wound decontamination was extremely slow. For a long time wound exudate shows the predominance of dystrophically changed neutrophils, while granulation tissue in the wound cavity if formed only at the 21st-24th day after the treatment commencement.     

Effect of experimental arrest of eye growth on the proliferation and polyploidization of the retinal pigment epithelium in rats

Following the lens removal from the left eye of the newborn rats, animals were obtained with one normal (control) and another microphtalmic eye. The animals were sacrificed on the 2nd, 3rd, 5th, 7th and 9th days of postnatal development after four injections of 3H-thymidine during 19 hrs. The number of labelled nuclei and mono- and binuclear cells in the central zone of the eye fundus was counted on the autographs. After the initial increase of the index of labelled nuclei in the operated eyes (on the 2nd, 3rd and 5th days) it fell below the control level (on the 7th and 9th days). The number of binuclear cells in the operated eyes, as well as in the control, attains on the 5th day 50% of the total number of cells and remains at this level up to the end of the experiment, whereas in the control eyes the number of binuclear cells increases up to 60% on the 7th and 80% on the 9th day. The results obtained have shown that in rats the factors of total eye growth participate in the control of proliferative activity and polyploidization of the pigment epithelium cells in the retina.     

Dissimilar hepatic protein expression profiles during the acute and flow phases following experimental thermal injury

The liver plays a major role in the early hypometabolic and later hypermetabolic phases after severe burn injury. Proteomic analysis was used to identify altered proteins in liver during these two phases. Sprague‐Dawley rats were subjected to a full‐thickness dorsal burn injury covering 40% of the total body surface area. Controls consisted of sham‐treated animals. Liver tissues were collected on postburn days 1 and 7. The proteomic data show greater production of positive acute phase proteins on day 1 than on day 7. Many antioxidant enzymes were coordinately downregulated on day 1, including the potent biliverdin reductase. These antioxidants were restored and in some cases upregulated on day 7. This opposite trend in the change of antioxidant proteins corroborated our finding of more pronounced oxidative stress on day 1 than on day 7 as measured via protein carbonyl content. The changes of metabolic enzymes on days 1 and 7 were consistent with hypo‐ and hyper‐metabolic states, respectively. Furthermore, a previously unreported decrease in ornithine aminotransferase on day 7 may be a key contributor to the observed increased urinary urea excretion during the hypermetabolic phase. Overall, the many differences in protein expression observed on postburn days 1 and 7 reflect the dissimilar hepatic metabolic patterns during the acute and flow phases following burn injury.     

Dynamic study of the development of edema in the organs in experimental burn trauma

Proton magnetic relaxation with measuring the time of spin-screen relaxation (T1) was used to study the time course of derangement of organ and tissue flooding after stage IIIB experimental burn of 15% body area. To examine the structures of the microcirculatory vessels, use was made of electron microscopy of the organs. The internal organs under study demonstrated a significant long-term (up to 49 days) increase in flooding: in the liver and kidneys, it occurred since the first day after burn, while in the lungs, myocardium and brain, since the 7th day. The results indicate the parallelism of the changes in the T1 and electron microscopic alterations in the histohematic barriers. Proton magnetic relaxation enables a more rapid and more convenient assay of the changes in tissue flooding as compared to the method of drying at high temperature. Therefore, it may be applied to the assessment of the efficacy of different therapeutic means.     

Possible role of CRF peptides in burn-induced hypermetabolism

Hypermetabolism and anorexia are significant problems associated with major burn trauma. Recent studies have shown that hypothalamic corticotropin releasing factor (CRF) elevates metabolic rate, while neuropeptide Y (NPY) reduces it. CRF also elicits anorexia, while NPY stimulates feeding. We hypothesized that elevation of CRF and decrease of NPY may be mediators of these negative effects of burn trauma. Therefore, we assessed concentrations of CRF and NPY in hypothalamus of burned rats one, three, and twenty-one days after a 30% body surface area, full-thickness, open flame burn. In addition we determined whether a biochemical lesion of CRF receptors using 3rd ventricle injections of a saporin-CRF conjugated peptide would decrease resting energy expenditure (REE). We found a three-day period of anorexia, with REE significantly increasing three days after the burn trauma. Concentrations of NPY were increased in the PVN-containing dorsomedial region of the hypothalamus 1 and 3 days after burn trauma, but were increased further in the day 1 pair-fed rats suggesting this change was a consequence of the anorexia. Levels of CRF were decreased in the ventromedial region of the hypothalamus in day 1 and day 3 burned and PF rats. Treatment with the saporin-CRF conjugate normalized REE and reduced CRF receptor-2 density in the hypothalamus of burned rats, and blocked CRF-induced hypermetabolism in sham-burned rats. Although these results suggest a role of CRF receptors in mediating burn-induced hypermetabolism, CRF itself may not be the principle ligand, as suggested by the significant elevation of hypothalamic urocortin 15 days after burn injury.     

Nω-硝基-L-精氨酸甲酯抑制吗啡镇痛耐受大鼠中脑和脊髓一氧化氮合酶/N-甲基-D-天冬氨酸受体表达上调

采用热甩尾测痛法观察全身应用非特异性一氧化氮合酶（nitric oxide synthase,NOS）抑制剂——N^ω-硝基-L-精氨酸甲酯（L-NAME）对吗啡镇痛耐受形成的影响,并通过观察脊髓和中脑神经元型NOS（nNOS）和N-甲基-D-天冬氨酸（NMDA）受体亚单位表达的变化来阐释NO／NMDA受体在吗啡镇痛耐受形成中的作用。将36只健康成年Sprague-Dawley大鼠平均分为6组（每组6只）：1组为对照组,皮下注射生理盐水1ml;2、3、4、5和6组为处理组,分别皮下注射L-NAME10mg／kg、L-NAME20mg／kg、吗啡10mg／kg、L-NAME10mg／kg＋吗啡10mg／kg、L-NAME20mg／kg＋吗啡10mg／kg,每天2次。在注射前测量大鼠的热甩尾潜伏期（tail-flick latency,TFL）基础值,随后每天第一次给药50min后测量其TFL。第8天最后一次给药80min后（除2组和5组之外）断头取脊髓和中脑,采用RT-PCR技术测量nNOS以及NMDA受体1A（NR1A）和2A（NR2A）亚单位的表达。结果显示,2组大鼠第1天至第7天的TFL与基础值相比无显著差异;3组第7天时的TFL仍显著高于基础值;4组的TFL在第1天时最高,第2至第6天期间逐渐降低,第6天时与基础值相比无显著差异：5组的TFL在实验过程中呈下降趋势,虽然第7天时较第1天有所降低,但是仍然显著高于基础值;6组的TFL变化趋势与5组相同。PT—PCR分析结果显示,与1组相比,3组脊髓和中脑的nNOS mRNA表达显著降低,但NR1A mRNA和NR2A mRNA表达无显著改变;4组的nNOS mRNA、NR1A mRNA和NR2A mRNA表达均显著高于1组。与4组相比,6组的nNOS mRNA、NR1A mRNA和NR2A mRNA表达均显著降低。结果提示,吗啡镇痛耐受大鼠脊髓和中脑的nNOS和NMDA受体表达增加,联合应用L—NAME可抑制长期应用吗啡所致的nNOS表达增加和NMDA受体上调,延缓吗啡镇痛耐受的形成。本研究结果提示,脊髓和中脑的NO／NMDA受体与吗啡镇痛耐受形成密切相关。     

Hypertonic saline dextran after burn injury decreases inflammatory cytokine responses to subsequent pneumonia-related sepsis

The present study examined the hypothesis that hypertonic saline dextran (HSD), given after an initial insult, attenuates exaggerated inflammation that occurs with a second insult. Adult rats (n = 15 per group) were divided into groups 1 (sham burn), 2 [40% total body surface area burn + 4 ml/kg isotonic saline (IS) + 4 ml.kg(-1).% burn(-1) lactated Ringer solution (LR)], and 3 (burn + 4 ml/kg HSD + LR), all studied 24 h after burns. Groups 4 (sham burn), 5 (burn + IS + LR), and 6 (burns + HSD + LR) received intratracheal (IT) vehicle 7 days after burns; groups 7 (burn + IS + LR) and 8 (burn + HSD + LR) received IT Streptococcus pneumoniae (4 x 10(6) colony-forming units) 7 days after burn. Groups 4-8 were studied 8 days after burn and 24 h after IT septic challenge. When compared with sham burn, contractile defects occurred 24 h after burn in IS-treated but not HSD-treated burns. Cardiac inflammatory responses (pg/ml TNF-alpha) were evident with IS (170 +/- 10) but not HSD (45 +/- 5) treatment vs. sham treatment (80 +/- 15). Pneumonia-related sepsis 8 days after IS-treated burns (group 7) exacerbated TNF-alpha responses/contractile dysfunction vs. IS-treated burns in the absence of sepsis (P < 0.05). Sepsis that occurred after HSD-treated burns (group 8) had less myocyte TNF-alpha secretion/better contractile function than IS-treated burns given septic challenge (group 7, P < 0.05). We conclude that an initial burn injury exacerbates myocardial inflammation/dysfunction occurring with a second insult; giving HSD after the initial insult attenuates myocardial inflammation/dysfunction associated with a second hit, suggesting that HSD reduces postinjury risk for infectious complications.     

Studies on implantation traces in rats. II. Staining of cleared uteri, formation and distribution of implantation traces

We made an investigation of implantation traces in delivered rats. 1. Non-fixed rat uteri were immersed in 2%-NaOH solution for over one hour. The uteri were then cleared and the implantation traces were seen to be stained yellowish-brown. This staining method was convenient for observation of the implantation traces. 2. Stillbirth was induced by stabbing or crushing, either in some embryos on one day between the 6th and 12th day of gestation, or in all embryos after the 13th day of gestation. Also, abortion was induced by stabbing or crushing all embryos before the 10th day of gestation. 3. When live embryos existed in the uterine horns, abortion traces were not detected. 4. In cleared uteri stained with 2%-NaOH solution, abortion traces were observed as small globes, reddish-brown. Normal delivery traces were observed as large globes, yellowish-brown, covered with yellowish-white of agglomerate cells, while stillbirth traces appeared as middle-sized, orange or yellowish-brown masses. 5. Though the implantation traces in rats which had been delivered four times were arranged like beads, they were recognizable by NaOH stain as either old or new traces, the former appearing smaller without agglomerate cells and a little more brown in comparison with the latter. 6. As the implantation traces increased in the uterine horns they became distributed from the central region to the cervical end, and the mean space between them narrowed. The implantation traces occupying the ovarian end or central region of the uterine horns trendes smallest size or largest size. 7. The implantation traces were composed of cicatrical tissue, and the area they occupied did not show adhesion of the placenta. On the other hand, placenta adhering to the uterine wall proliferated, and formed new implantation traces which did not overlap the old traces after decollement of the placenta.     

The effect of alpha and beta adrenergic blockade on Ni induced coronary spasm in scalded rats

After 20% total body surface scalding inducing 3d degree burn in rats the following parameters were studied in ebb and flow phases, as well as in burn disease, 2 hours, 2 and 7 days postburn: atomic absorption spectrophotometric study of the serum and myocardial Ni levels; the effect of Ni ions (10(-8)-10(-4) M/l) in vitro on total coronary resistance in the isolated perfused rat heart; the effect of alpha and beta adrenergic blocking agents (phenoxibenzamine, oxprenolol) on Ni-induced coronary vasoconstriction; electron cytochemical study of the ultrastructural changes of the myocardium 7 days after scalding. It was found that: During the first 2-3 hours after scalding or bleeding there was a significant elevation of serum Ni level which levelled off by the end of the first week. Total coronary resistance (TCR) increasing effect of Ni ions was significantly augmented during the first 2-3 hours after burn and bleeding (ebb phase). In the scalded group it decreased to the control value by the 2-3d day (flow phase) and increased again a week later (burn disease). In the scalded groups in vivo pretreatment with oxprenolol (10(-4) g/kg) completely inhibited the Ni induced coronary spasm. PBZ treatment in vitro (10(-5) M/l) had similar effect in the three postburn periods tested. Ultrastructural changes and intracellular Ni-dimetilglyoxim complexes could be detected. Oxprenolol treatment continuously applied from the 4th day postburn (2 X 0.5 mg/kg) prevented the development of myocardial damage, while the electron dense complexes containing Ni were still detectable. In view of our previous data we assume that the endogenous Ni increase in the serum after burn may be cardiopathogenic. The phasic changes of the sensitivity of the coronary vessels to Ni ion and the similarity of the effects of alpha and beta adrenergic blocking agents may be explained by the alterations in the neuroendocrine system and metabolic disturbances.     

Role of epidermal stem cells in repair of partial-thickness burn injury after using Moist Exposed Burn Ointment (MEBO) histological and immunohistochemical study

Moist Exposed Burn Ointment (MEBO^®) is widely used topical agent applied on skin burn. This study investigated the effect of MEBO topical application on activation and proliferation of epidermal stem cells through the immunohistochemical localization of cytokeratin 19 (CK19) as a known marker expressed in epidermal stem cells. Biopsies from normal skin and burn wounds were taken from 21 patients with partial thickness burn 1, 4, 7, 14, 21, and 28 days after treatment with MEBO. Tissue sections were prepared for histological study and for CK19 immunohistochemical localization. In control skin, only few cells showed a positive CK19 immune-reaction. Burned skin showed necrosis of full thickness epidermis that extended to dermis. Gradual regeneration of skin accompanied with an enhancement in CK19 immune-reactivity was noted 4, 7, 14 and 21 days after treatment with MEBO. On day 28, a complete regeneration of skin was observed with a return of CK19 immune-reactivity to the basal pattern again. In conclusion, the enhancement of epidermal stem cell marker CK19 after treatment of partial thickness burn injuries with MEBO suggested the role of MEBO in promoting epidermal stem cell activation and proliferation during burn wound healing.