肺出血幼兔右心室压力及肺毛细血管内皮细胞超微结构的改变

目的　研究肺出血幼兔肺动脉压力及肺血管内皮细胞超微结构的变化 ,为预防新生儿肺出血提供理论依据。方法　 15只幼兔耳缘静脉注射高分子右旋糖苷 (T 5 0 0 ) 1ml/kg,连续 5d (7只 )和 8d (8只 )。对照组 (8只 )注射相同剂量的生理盐水 ,连续 5d。经右心室穿刺 ,通过多道生理记录仪记录右心室压力 ,并以此反映肺动脉压力。透射电镜观察肺血管内皮细胞超微结构变化。结果　实验组幼兔右心收缩压第 5天为 (16 6± 1 2 )mmHg (1mmHg =0 .133kPa) ,第 8天为 (19 2±1 1)mmHg ,明显高于对照组的 (12 2± 1.3)mmHg(P <0 .0 1)。超微结构表现为肺动脉内皮细胞水肿 ,肺泡毛细血管内皮细胞破坏 ,II型上皮细胞内层状小体空泡变性。结论　高粘滞血症引起幼兔肺出血 ,伴有肺动脉压力显著升高及肺毛细血管内皮细胞和肺泡上皮细胞超微结构异常。这些改变是高粘滞血症导致幼兔发生肺出血的病理基础。     

Changes of Fibrinolysis and Their Relationship with Pulmonary Artery Pressures in Neonates with Lung Diseases

目的　研究新生儿肺疾病的纤溶改变及其与肺动脉压力的关系。方法　用发色底物法测定 2 7例新生儿肺疾病患儿 (病例组 )及 2 5例正常新生儿 (对照组 )血浆组织纤溶酶原激活剂 (TPA)和纤溶酶原激活抑制物(PAI)活性变化 ;用超声多普勒方法测定肺动脉血流加速时间 (TPV)与右室射血时间 (RVET)之比值 (TPV/RVET) ,以此估计新生儿肺动脉压力 (TPV/RVET比值与肺动脉压力成反比 )。结果　病例组PAI活性 [(9.3±4 .1)AU× 10 -1/ml]明显高于对照组 [(5 .5± 3.0 )AU× 10 -1/ml],P <0 .0 1,TPV/RVET比值 (0 .2 9± 0 .0 5 )明显低于对照组 (0 .34± 0 .0 8) ,(P <0 .0 5 ) ;发生肺出血者肺动脉压力 [TPV/RVET (0 .2 3± 0 .0 2 ) ]显著升高 ,P <0 .0 5。肺出血恢复期新生儿TPA [(3.7± 1.7)IU× 10 -1/ml]及血小板 [(180± 30 )× 10 9/L]明显高于肺出血发生时 [TPA (1.8± 0 .7)IU× 10 -1/ml,血小板 (98± 39)× 10 9/L],(P <0 .0 1)。结论　新生儿肺疾病时由于肺动脉压力增高 ,肺血管内皮细胞破坏 ,导致TPA释放减少 ,PAI活性增高 ,纤溶活性降低。     

1,6-二磷酸果糖对大鼠缺血性心脑损伤的保护作用

目的　探讨口服 1,6 二磷酸果糖 (FDP)对大鼠缺血性心脑组织损伤的保护作用及其作用机制。方法　采用异丙肾上腺素 (Iso)致大鼠实验性心肌缺血模型。随机分为 3组 :对照组、Iso组 [5mg/(kg·d) ,7d]和Iso +FDP组 [Iso ,5mg/(kg·d) ,7d ;FDP ,6 g/(kg·d) ,2 1d],每组 8只。用光镜、电镜观察心、脑组织病理形态学改变。测定心肌肌浆网钙泵 (SERCA)活性、超氧化物歧化酶 (SOD)活性。结果　Iso组大鼠心肌组织病理可见大量纤维化病灶 ,病灶多呈片状、多灶性 ,还可见少许凝固坏死灶 ;亦可见脑组织病理损害、海马神经元密度较对照组降低。心肌SERCA活性 [0 .2 5 0± 0 .0 6 3μmol/(min·g·wetweight) ]较对照组 [0 .334± 0 .0 6 1μmol/(min·g·wetweight) ]降低。脑组织匀浆SOD活性 [2 3.2 2± 3.0 7U/(mg·pro) ]低于对照组 [4 4 .89± 2 .771U/(mg·pro) ]。FDP使心肌组织纤维化病灶减少 ,脑组织损害也明显减轻 ;FDP使心肌SERCA活性 [0 .312± 0 .0 6 7μmol/(min·g·wetweight) ]和SOD活性 [39.70± 3.4 4 1U/(mg·pro) ]增高。结论　口服FDP可减轻大鼠心肌和脑组织病理改变 ,从而起到心脑保护作用     

新生儿呼吸窘迫综合征肺动脉压力动态变化及其与血清内皮素-1和一氧化氮关系的研究

目的研究新生儿呼吸窘迫综合征(RDS)肺动脉压力动态变化及其与血清内皮素-1(endothelin-1,ET-1)、一氧化氮(nitric oxide,NO )的关系.方法对13例确诊为新生儿RDS患儿(实验组)和20例正常新生儿(对照组)用脉冲超声多谱勒分别于生后2、12、24、48、72 h测定肺动脉血流加速时间(TPV)及右心室射血时间(RVET),以TPV/RVET比值反映肺动脉压力.用硝酸还原酶法和放射免疫法分别测定实验组和对照组新生儿生后24、72 h血清ET-1和NO的水平.结果实验组和对照组新生儿肺动脉压力在生后2、12及72 h差异无显著意义(t值分别为1.25、1.84、0.94,P均>0.05);实验组24、48 h TPV/RVET比值为0.277±0.076、0.278±0.027,对照组分别为0.321±0.051、0.329±0.062,两组相比差异有显著意义(t值分别为2.86、2.20,P＜0.01、 <0.05);实验组和对照组在生后24 h时ET-1[(62±23)ng/L、(47±8)ng/L]、NO[(11±10) μmol/L、(32±22) μmol/L]水平相比,差异有显著意义(t值分别为2.33、2.37,P均<0.05);而72 h时差异无显著意义(t值分别为0.87、1.93,P均＞0.05),与肺动脉压力变化相一致.死亡组肺动脉压力(0.25±0.02)明显高于存活组(0.28±0.03, t=2.35, P＜0.05);死亡组患儿ET-1水平[(91±27)ng/L]明显高于存活组[(39±9)ng/L],差异有显著意义(t=4.97,P＜0.01);死亡组患儿NO水平为(5±4) μmol/L,明显低于存活组的(32±28) μmol/L, 差异有显著意义(t=2.38,P＜0.05);实验组RDS患儿生后24 h其血清ET-1水平与肺动脉压力呈正相关y=302.3x-861.2,NO水平与肺动脉压力呈负相关y=-98.3x+400.8.结论新生儿RDS患儿肺动脉压力较正常儿高,持续时间较长,且易合并持续肺动脉高压.血清ET-1水平与肺动脉压力呈正相关,NO水平与肺动脉压力呈负相关.     

一氧化氮吸入治疗新生儿肺动脉高压疗效的初步评价

利用彩色多普勒超声心动图技术 ,评价一氧化氮 (NO)吸入治疗新生儿肺动脉高压的疗效。对 8例新生儿因肺炎、肺透明膜病、持续胎儿循环和先天性支气管肺发育不良并发呼吸衰竭而采用机械通气和NO吸入治疗。NO吸入浓度为 3～2 0ppm ,吸入时间为 1小时～ 35天。多普勒超声心动图利用三尖瓣返流或动脉导管未闭定量估测NO吸入前后肺动脉收缩压 (SPAP) ,同时测量上肢收缩压 (SBP) ,计算肺 /体压力 (Pp/Ps)比值。结果显示 :NO吸入 30～ 1 2 0分钟和 1 8～ 2 4小时后 ,SPAP分别由NO吸入前的 5 7± 1 1 .6mmHg降至 41± 1 0 8mmHg和 43± 1 8 2mmHg ;Pp/Ps分别由 0 87± 0 1 5降至 0 6 1± 0 1 5和 0 6 3± 0 2 1。NO吸入前后SBP无明显变化。NO吸入后卵圆孔、动脉导管和室间隔缺损水平右向左或双向分流较吸入前明显减少。结论　NO吸入治疗新生儿肺动脉高压安全有效。彩色多普勒超声心动图技术对于指导NO的临床应用具有重要价值     

吸入一氧化氮治疗大鼠缺氧性肺动脉高压

目的　 观察吸入一氧化氮 (NO)对慢性和急性缺氧所致大鼠肺动脉高压的作用。 方法 　分别利用雄性Wistar大鼠 3 0只 ,制备慢性和急性缺氧肺动脉高压模型。实验中监测肺动脉压、血气、高铁血红蛋白含量 (Met % )等指标。 结果 　慢性缺氧大鼠吸入 2 0 ppm、40ppmNO ,肺动脉平均压 (MPAP)由治疗前 (2 5 2± 3 5 )mmHg降到 (2 2 4± 3 5 )mmHg及 (2 1 8± 3 3 )mmHg ,而对动物体循环血压无明显影响 ;急性缺氧大鼠吸入 2 0 ppm、40 ppmNO 1hMPAP分别由缺氧时 (2 2 8± 2 7)mmHg、(2 4± 2 8)mmHg下降到 (19 6± 4 7)mmHg和 (2 0 5± 4 1)mmHg。吸入NO 4h ,2 0ppm组Met %由 (0 40± 0 3 9) %升到 (0 95±0 75 ) % ,40 ppm组由 (0 3 9± 0 3 2 ) %升到 (1 2 6± 0 49) %。肺病理组织检查显示 :2 0 ppm、40 ppm组与对照组无显著差别。 结论 　吸入NO对慢性和急性缺氧肺动脉高压具有选择性扩张肺血管的作用 ,急性缺氧大鼠持续吸入NO 4h不会引起高铁血红蛋白血症 ,对肺组织结构无重要影响     

高肺血流所致肺血管结构重建时内源性一氧化氮体系的研究

目的　探讨高肺血流所致肺血管结构重建时内源性一氧化氮 (NO)体系的变化。方法对大鼠行腹主动脉 下腔静脉分流术。 11周后以右心导管法测定肺动脉平均压 (mPAP) ,检测右心室 /左心室 +室间隔 [RV/(LV +S) ]的比值。观测肺血管显微及超微结构的变化 ,并且以分光光度计测定血浆NO含量 ,分别以原位杂交和免疫组织化学的方法检测肺动脉内皮型NO合酶 (eNOS)mRNA和蛋白的表达。结果　分流组大鼠mPAP明显高于对照组 [分别为 (2 2 5± 2 6)mmHg、(15 8± 2 8)mmHg,1mmHg =0 13 3kPa ,P <0 0 1],RV/(LV +S)比值也明显增加。光镜下 ,肺小血管肌化程度明显增强 ,肺中、小型肌型动脉相对中膜厚度明显增加。电镜下 ,肺腺泡内动脉内皮细胞增生、变性 ,内弹力层粗细不均 ,平滑肌细胞肥厚、向合成表型转化。并且分流组大鼠血浆NO含量明显高于对照组 [分别 (为3 0 2± 7 9) μmol/L、(19 7± 5 7) μmol/L ,P <0 0 1],肺动脉eNOSmRNA和蛋白表达均明显增强。 结论　NO体系 eNOSmRNA表达、eNOS蛋白表达及血浆NO含量上调在高肺血流所致肺动脉高压和肺血管结构重建的形成中起重要的调节作用     

呼气末正压对婴儿室间隔缺损术后心肺功能的影响

目的　 探讨婴儿先天性心脏病室间隔缺损 (窒缺 )修补术后机械通气时的最佳PEEP ,研究不同PEEP对其呼吸及心功能的影响。 方法 　选择体重小于 10kg ,术后畸形纠正满意者 ,共 15例。在PEEP 2、5、8、12cmH2 O时 ,分别测量呼吸系统顺应性(Cdyn)、气道阻力 (Raw)、生理死腔 (VD/TT)、动脉血氧分压 (PaO2 )、动脉血氧饱和度 (SaO2 )、氧合指数 (OI)、心率 (HR)、血压 (BP)、心输出量 (CO)、心排指数 (CI)、全身血管阻力 (SVR)、氧运输 (DO2 )。 结果　在PEEP 8cmH2 O时 ,Cdyn达高峰为 ( 5 16± 1 77)ml/cmH2 O(P <0 0 1) ,Raw和VD/VT 分别达最低值 ( 3 2 10± 17 2 3 )cmH2 O/ (L·s) (P <0 0 1)和 ( 0 5 5± 0 15 ) (P <0 0 1)。当PEEP从2cmH2 O渐增至 12cmH2 O时 ,HR、BP无显著性差异。CO和CI在 8cmH2 O时达高峰为 ( 2 2 9± 0 72 )L/min(P <0 0 1)和 ( 5 60±1 92 )L/ (min·m2 ) (P <0 0 1) ,SVR达最低值为 ( 881 6± 3 0 4 5 )Dyn .S/cm- 5(P <0 0 5 )。DO2 在 8cmH2 O时达高峰为 ( 997 5±3 44 6)ml/ (min·m2 ) (P <0 0 1)。 结论 　婴儿室缺术后 ,适当的PEEP可以改善呼吸功能和心血管功能 ,8cmH2 O是本组婴儿室缺术后的最佳PEEP ,可使DO2 达到最大化。     

幼兔胎粪吸入后肺表面活性蛋白B动态改变及与右心室压力关系的探讨

目的　探讨胎粪吸入综合征 (MAS)并发持续肺动脉高压 (PPHN)的发病机制。方法(1)通过气管内灌入胎粪 0 .6ml kg和 4ml kg建立轻、重度幼兔胎粪吸入模型 ;(2 )应用右心室穿刺法经压力传感器与日本光电公司生产的RM 6 0 0 0型多道生理记录仪相连 ,测定轻度胎粪吸入组 16、2 4、48、72h和重度胎粪吸入组右心室收缩压 ;(3)用RT PCR检测技术检测肺表面活性物质蛋白B(SP B)mRNA的水平。结果　 (1)轻度胎粪吸入组右心室收缩压从胎粪吸入后 16h开始升高 (19.3± 0 .8)mmHg(1mmHg=0 .133kPa) ,2 4h达高峰 (2 6 .8± 1.1)mmHg,72h恢复正常 (14.2± 0 .3)mmHg。重度胎粪吸入组右心室收缩压为 (32 .7± 1.1)mmHg ,明显高于轻度胎粪吸入组和对照组 (q值分别为17.5 6、5 5 .78,P均 <0 .0 1) ;(2 )轻度胎粪吸入组肺组织SP BmRNA吸光度 (A值 )较对照组降低 ,2 4～48h达最低水平 ,为 (0 .74± 0 .0 8) ,72h基本恢复正常 (1.84± 0 .10 ) ,重度胎粪吸入组SP BA值为(0 .2 0± 0 .0 5 ) ,较轻度胎粪吸入组降低更明显。SP BmRNA的A值与右心室压亦呈明显负相关 (r =- 0 .84,P <0 .0 1,n =30 )。结论　 (1)胎粪吸入后肺表面活性物质减少 ,并与胎粪吸入浓度有关 ,提示MAS时肺病理生理改变及其严重程度与其表面活性物质功能障碍有     

对新生儿窒息不同复苏方法的比较分析

目的　探讨抢救新生儿窒息快速有效的方法。方法　取新生儿窒息 135例 ,根据窒息程度将 135例分为轻度窒息组 (A组 ,4≤ 1minApgar评分≤ 7,n =99)和重度窒息组 (B组 ,0 <1minApgar评分≤ 3,n =36 ) ,每组处理上有采用口腔吸引后面罩辅助控制通气 (方法 1) ,也有采用气管插管吸引后辅助控制通气 (方法 2 )。结果　方法 2与方法 1相比 ,5minApgar评分显著增高 [A2 vsA1=(9 3± 0 6 )vs(7 8± 0 3) ,P <0 0 5 ;B2 vsB1=(8 5± 0 4 )vs(6 7± 0 6 ) ,P <0 0 1],复苏处理时间显著缩短 [A2 vsA1=(5 7± 1 2 )vs(8 6± 1 4 ) ,P <0 0 5 ;B2 vsB1=(8 1± 1 8)vs(11 3± 2 2 ) ,P <0 0 1]。结论　采用气管插管辅助人工通气对新生儿窒息 ,特别对重度新生儿窒息是一种快速有效的复苏方法     

Allergic factors associated with the development of asthma and the influence of cetirizine in a double-blind, randomised, placebo-controlled trial: First results of ETA®

There is a common progression known as the allergic march from atopic dermatitis to allergic asthma. Cetirizine has several antiallergic properties that suggest a potential effect on the development of airway inflammation and asthma in infants with atopic dermatitis. Methods. Over a two year period, 817 infants aged one to two years who suffered from atopic dermatitis and with a history of atopic disease in a parent or sibling were included in the ETAC^® (Early Treatment of the Atopic Child) trial, a multi-country, double-blind, randomised, placebo-controlled trial. The infants were treated for 18 months with either cetirizine (0.25mg/ kg b.i.d.) or placebo. The number of infants who developed asthma was compared between the two groups. Clinical and biological assessments including analysis of total and specific IgE antibodies were performed. Results. In the placebo group, the relative risk (RR) for developing asthma was elevated in patients with a raised level of total IgE (≥ 30 kU/I) or specific IgE (≥ 0.35 kUA/I) for grass pollen, house dust mite or cat dander (RR between 1.4 and 1.7). Compared to placebo, cetirizine significantly reduced the incidence of asthma for patients sensitised to grass pollen (RR = 0.5) or to house dust mite (RR = 0.6). However, in the population that included all infants with normal and elevated total or specific IgE (intention-to-treat - ITT), there was no difference between the numbers of infants developing asthma while receiving cetirizine or placebo. The adverse events profile was similar in the two treatment groups. Discussion. Raised total IgE level and raised specific IgE levels to grass pollen, house dust mite or cat dander were predictive of subsequent asthma. Cetirizine halved the number of patients developing asthma in the subgroups sensitised to grass pollen or house dust mite (i.e. 20% of the study population). In view of the proven safety of the drug, we propose this treatment as a primary pharmacological intervention strategy to prevent the development of asthma in specifically sensitised infants with atopic dermatitis.     

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孤独症谱系障碍(autistic-spectrum disorders,ASDs)近年来患病率逐年攀升至1%左右,其症状往往伴随终生,成为严重威胁儿童健康和发展的神经发育性疾患;注意缺陷多动障碍(attention deficit hyperactivity disorder,ADHD)是儿童期最常见的精神障碍,国内报道患病率为4.13%～5.83%,其症状可延续至青少年期,甚至到成年期[1]。这两类精神障碍在成年期的临床表现、共患病、治疗策略和预后与儿童期有哪些不同呢?本文通过回顾相     

EXCITING NEW TREATMENT APPROACHES FOR PATHYPHYSIOLOGIC MECHANISMS OF SICKLE CELL DISEASE

During the past several decades, our understanding of the complex pathophysiology of vasoocclusion associated with sickle cell disease has improved greatly. Interaction of genes, hemoglobin molecules, red cell membrane and metabolic changes, cell-cell interactions and cell-plasma interactions, red cell adhesion to vascular endothelium, activation of coagulation, and vascular reactivity play a role in vaso occlusion. Penicillin prophylaxis of pneumococcal infections and appropriate use of blood transfusions and other supportive measures improved survival of sickle cell patients. Hydroxyurea made a major impact on sickle cell therapy when it was shown to decrease acute painful episodes, acute chest syndrome, and the need for blood transfusion in adults. Significant experience in the use of hydroxyurea has been accumulated in older children. The benefits and risks of hydroxyurea for younger children and long-term risks in all patients will be evaluated in future investigations. Other promising therapies include butyrate compounds, clotrimazole, magnesium supplementation, poloxamer 188, antiadhesion agents, anticoagulant approaches, and nitric oxide. Hemopoietic transplantation remains the only curative therapy. However, several transgenic mouse models are available for studies of gene therapy or other treatment approaches on biochemical, cellular, and pathologic effects of mutant genes.     

Infiltrations of Epstein-Barr virus-carrying cells in granular lymphocyte-proliferative disorders corresponding to chronic active Epstein-Barr virus infection

A 21-year-old man with granular lymphocyte-proliferative disorders (GLPD) associated with chronic active Epstein-Barr virus (EBV) infection is described. Chromosomal analyses revealed several clonal abnormalities and two of them were mainly repetitious. High copy numbers of monoclonal EBV genome were also detected in the proliferative large granular lymphocytes (LGLs), indicating the monoclonal expansion of EBV-infected LGLs. The patient had an indolent course for several years, and there was no evidence of infiltrations of his bone marrow until the end stage. At autopsy, microscopic studies revealed marked infiltrations of LGL in the liver and spleen, and the infiltrating cells were NK-cell immunophenotype. The infiltrated LGLs showed latency I.     

LUTEINIZING HORMONE RECEPTOR MUTATIONS IN DISORDERS OF SEXUAL DEVELOPMENT AND CANCER

Human male sexual development is regulated by chorionic gonadotropin (CG) and luteinizing hormone (LH). Aberrant sexual development caused by both activating and inactivating mutations of the human luteinizing hormone receptor (LHR) have been described. All known activating mutations of the LHR are missense mutations caused by single base substitution. The most common activating mutation is the replacement of Asp-578 by Gly due to the substitution of A by G at nucleotide position 1733. All activating mutations are present in exon 11 which encodes the transmembrane domain of the receptor. Constitutive activity of the LHR causes LH releasing hormone-independent precocious puberty in boys and the autosomal dominant disorder familial male-limited precocious puberty (FMPP). Both germline and somatic activating mutations of the LHR have been found in patients with testicular tumors. Activating mutations have no effect on females. The molecular genetics of the inactivating mutations of the LHR are more variable and include single base substitution, partial gene deletion, and insertion. These mutations are not localized and are present in both the extracellular and transmembrane domain of the receptor. Inactivation of the LHR gives rise to the autosomal recessive disorder Leydig cell hypoplasia (LCH) and male hypogonadism or male pseudohermaphroditism. Severity of the clinical phenotype in LCH patients correlates with the amount of residual activity of the mutated receptor. Females are less affected by inactivating mutation of the LHR. Symptoms caused by homozygous inactivating mutation of the LHR include polycystic ovaries and primary amenorrhea.     

Resurgence of measles in Singapore: profile of hospital cases

OBJECTIVE: To ascertain the profile of cases of measles seen at a general hospital during a recent outbreak that occurred despite a measles vaccination program. METHODOLOGY: A retrospective study from January 1991 to March 1998. All patients with measles (ICD code 055. 9) seen at the emergency unit or as inpatients were included. RESULTS: There were 87 cases identified. The diagnosis was clinical in all and proven serologically in 71%. Eighty-five per cent of the cases occurred between January 1997 and March 1998. There was a bi-modal age distribution with peaks in the very young (相似文献   

Personality profiles and heart rate variability (vagal tone) in children with recurrent abdominal pain

The aim of the study was to explore psychological factors and autonomic activity in children with recurrent abdominal pain and to compare them with those in a control group of healthy children. The Personality Inventory for Children was used for assessment of developmental, emotional and psychosocial factors in 25 children with recurrent abdominal pain (age, 7-15 y). Parasympathetic and sympathetic functions in these children and in 23 healthy control subjects (age, 7-13 y) were also investigated, non-invasively using a computerized polygraph. Vagal tone (parasympathetic function) was indexed by calculation of respiratory sinus arrhythmia in beats/min. Skin conductance (sympathetic function) was recorded by the constant current method. On the Personality Inventory for Children, 16 patients had high scores on somatic concern. Several patients had scores in the clinical range for depression, withdrawal and anxiety, but the mean scores for these personality profile scales were well within the normal range of healthy children. Interestingly, there was a spike on the L (Lie)-scale for most of the patients and 15 patients had scores above or close to the clinical cut-off value. As compared with the scores in healthy children, vagal tone and sympathetic tone were normal. Conclusion: Many children with recurrent abdominal pain have scores in the clinical range for depression, withdrawal, anxiety and L-scale indicating coping problems, denial and a trend towards somatic concern that may contribute to the evolution of abdominal pain. Autonomic nerve activity was not disturbed in these children.     

Overcoming surfactant inhibition with polymers

Inhibition of the function of pulmonary surfactant in the alveolar space is an important element of the pathophysiology of many lung diseases, including meconium aspiration syndrome, pneumonia and acute respiratory distress syndrome. The known mechanisms by which surfactant dysfunction occurs are (a) competitive inhibition of phospholipid entry into the surface monolayer (e.g. by plasma proteins), and (b) infiltration and destabilization of the surface film by extraneous lipids (e.g. meconium-derived free fatty acids). Recent data suggest that addition of non-ionic polymers such as dextran and polyethylene glycol to surfactant mixtures may significantly improve resistance to inhibition. Polymers have been found to neutralize the effects of several different inhibitors, and can produce near-complete restoration of surfactant function. The anti-inhibitory properties of polymers, and their possible role as an adjunct to surfactant therapy, deserve further exploration.     

Understanding infant formula

The World Health organisation recommends breast feeding infants for the first six months of life. When this breast feeding does not occur either through parental choice or medical need, infant formulas will be required. There is a bewildering array of formulas on the UK market for many different requirements. When faced with an unsettled infant many parents (and healthcare professionals) will experiment with the infant formula available and then attend the paediatric clinic looking for help and advice. It is therefore essential that paediatricians understand what milks are available and what the key differences between different products are. This review attempts to provide a simple guide through many of the formulations currently available in the UK; and offers advice for the dietary management of the child with extra calorie requirements, infants with cow's milk protein allergy, gastro oesophageal reflux disease, apparent unresolved hunger and infantile colic. Whatever the underlying condition, there is likely to be an infant formula that is suitable in this generation of ever expanding formulations.