Serum neopterin for early assessment of severity of severe acute respiratory syndrome

Neopterin and C-reactive protein (CRP) concentrations were determined in serum samples from 129 severe acute respiratory syndrome (SARS) patients and 156 healthy blood donors. In the patients with confirmed SARS, an early neopterin elevation was detected already at the day of onset of symptoms and rose to a maximum level of 45.0 nmol/L 3 days after the onset. All SARS patients had elevated neopterin concentrations (>10 nmol/L) within 9 days after the onset. The mean neopterin concentrations were 34.2 nmol/L in acute sera of SARS patients, 5.1 nmol/L in convalescent sera, and 6.7 nmol/L in healthy controls. In contrast, the mean CRP concentrations in both acute and convalescent sera of SARS patients were in the normal range (<10 mg/L). Serum neopterin level in SARS patients was associated with fever period and thus the clinical progression of the disease, while there was no significant correlation between the CRP level and the fever period. Serum neopterin may allow early assessment of the severity of SARS. The decrease of neopterin level was found after steroid treatment, which indicates that blood samples should be collected before steroid treatment for the neopterin measurement.     

SARS冠状病毒棘突蛋白的S1蛋白诱导小鼠产生中和抗体的研究

目的 研究SARS冠状病毒棘突蛋白受体结合部位S1的免疫原性，为SARS的实验诊断和新型疫苗的研究提供依据。方法 用克隆有哺乳动物细胞密码子优化的SARS-CoV S1基因的质粒pcDNA3．1／S1或P-S1Ig转染293T细胞，用细胞的上清液纯化S1蛋白。以pcDNA3．1／S1质粒对BALB／c小鼠进行2次基因免疫，以纯化的S1蛋白进行加强免疫。用ELISA法检测小鼠抗SARS-CoV的特异性IgG抗体，并在Vero E6细胞上做体外中和实验，检测中和抗体。结果 S1蛋白诱导小鼠产生抗SARS-CoV的特异性抗体；1：1499．68稀释的S1蛋白免疫的小鼠血清可保护50％的细胞对1000TCID50的病毒攻击，而阴性对照血清不能保护细胞对病毒的感染。结论 SAPS冠状病毒棘突蛋白受体结合部位S1能有效诱导机体产生具有高效保护作用的中和抗体免疫反应，可望发展成为理想的SARS棘突蛋白亚单位疫苗。     

严重急性呼吸综合征患者尸解肺标本的病理改变和致病机制研究

目的研究严重急性呼吸综合征（SARS）患者尸解肺标本的病理改变和致病机制。方法观察了2003年4-7月期间死于SARS的6例患者的肺标本,并采用光镜、电镜、Masson三色染色和免疫组织化学染色方法（EnVision法）进行研究。结果肺标本的病理形态改变：（1）6例的双肺均可见到弥漫性实变病灶,肺重量明显增加;（2）6例均可见到弥漫性肺泡损伤,包括透明膜形成、肺泡腔内水肿／出血、纤维素沉积和肺泡上皮细胞脱屑,AE1／AE3免疫组织化学染色显示肺泡上皮细胞的完整性明显破坏;（3）Ⅱ型肺泡上皮细胞轻度增生,有一定异型性,细胞体积增大,胞质呈双染性和颗粒状,胞质内可见小脂肪空泡聚集（5／6）;（4）6例中有5例可见巨细胞在肺泡内浸润,巨细胞大多AEl／AE3阳性（5／6）,少数CD68阳性（2／6）;（5）组织学形态和免疫组织化学染色证实肺泡腔内和肺泡间隔内有多量巨噬细胞浸润（6／6）;（6）6例中有5例可见巨噬细胞噬红细胞象;（7）6例中有5例可见肺纤维化,包括肺泡间隔和肺间质增宽（5／6）、肺泡腔内渗出物机化（6／6）和胸膜增厚（4／6）。Masson三色染色证实胶原纤维明显增生,免疫组织化学染色显示大多数为Ⅲ型胶原。光镜和免疫组织化学染色显示5例有明显的成纤维细胞／肌纤维母细胞增生灶;（8）5例可见支气管黏膜鳞状上皮化生;（9）6例患者均可见血栓;（10）2例同时合并其他感染,1例合并细菌感染,另1例合并真菌感染。此外,电镜发现在肺泡上皮细胞和肺血管内皮细胞的胞质内有冠状病毒样颗粒。结论SARS冠状病毒直接损伤肺泡上皮细胞、巨噬细胞明显浸润和成纤维细胞／肌纤维母细胞显著增生在SARS的致病机制中起重要作用。     

Four new adenosine deaminase mutations,altering a zinc-binding histidine,two conserved alanines,and a 5′ splice site

Three new missense mutations (H15D, A83D, and A179D) and a new splicing defect (573 + 1G→A) in the 5′ splice site of intron 5 were among six mutant adenosine deaminase (ADA) alleles found in three unrelated patients with severe combined immunodeficiency disease, the most common phenotype associated with ADA deficiency. When expressed in vitro, the H15D, A83D, and A179D proteins lacked detectable ADA activity. The splicing defect caused skipping of exon 5, resulting in premature termination of translation and a reduced level of mRNA. H15D is the first naturally occurring mutation of a residue that coordinates directly with the enzyme-associated zinc ion. Molecular modeling based on the atomic coordinates of murine ADA suggests that the D15 mutation would create a cavity or gap between the zinc ion and the side chain carboxylate of D15. This could alter the ability of zinc to activate a water molecule postulated to play a role in the catalytic mechanism. A83 and A179 are not directly involved in the active site, but are conserved residues located respectively in a helix 4 and β strand 4 of the α/β barrel. Replacement of these small hydrophobic Ala residues with the charged, more bulky Asp side chain may distort ADA structure and affect enzyme stability or folding.© 1995 wiley-Liss, Inc.     

X-linked severe combined immunodeficiency syndrome: the first Korean case with gamma c chain gene mutation and subsequent genetic counseling

X-linked severe combined immunodeficiency (X-SCID) is a rare, life-threatening immune disorder, caused by mutations in the gamma c chain gene, which encodes an essential component of the cytokine receptors for interleukin-2 (IL-2), IL-4, IL-7, IL-9, IL-15, and IL-21. A 13-month-old boy with recurrent infections who had reduced serum immunoglobulin levels and decreased numbers of CD3, CD16/56 cells was evaluated for gamma c chain gene mutation and protein expression. The patient had a C-to-T point mutation at nucleotide position 690, one of the hot spots, resulting in a single amino acid substitution of cysteine for arginine (R226C), as determined by direct sequencing and PCR-RFLP. The patient's mother was a heterozygous carrier. Percutaneous umbilical cord blood sampling was performed at the 6-month of gestation in a subsequent pregnancy. As the immunophenotype of the fetus showed an identical pattern, the pregnancy was terminated and genetic analysis of the abortus confirmed recurrence. This is the first report of the molecular diagnosis of X-SCID in Korea. Genetic analysis of the gamma c chain gene is useful for definite diagnosis and genetic counseling for X-SCID.     

7例SARS患者治疗的临床研究

目的　进行严重急性呼吸综合征 (SARS)的临床研究。方法　对 2 0 0 4年 4月 2 2日在地坛医院收治的 7例确诊SARS患者进行回顾性分析。结果　 7例确诊SARS患者 ,男性 2例、女性 5例 ,年龄 2 0～ 4 9岁 ,平均年龄为 (35 3± 11 3)岁。临床症状主要表现为发热、咳嗽、不同程度的呼吸困难、全身不适、恶心、呕吐等 ,肺部可闻及湿音 ,可伴有肺外损伤。临床治疗中采用综合治疗原则 ,包括氧疗 ;小剂量、短期应用甲泼尼龙 ,剂量为每天 1～ 2mg kg;及时应用呼吸机 ;必要的心理干预及支持治疗等 ,患者均好转。结论　合理应用糖皮质激素 ,及时使用呼吸机是SARS治疗的关键。     

SARS患者血清IL-8、IL-12和TGF-β1的检测及意义

目的 :探讨SARS患者血清IL 8、IL 12和TGF β1在SARS冠状病毒感染致病中的作用。 方法 :应用酶联免疫吸附法 (ELISA)测定广州地区 2 8例SARS冠状病毒感染患者双份血清IL 8、IL 12和TGF β1的水平。实验数据采用两样本均数t检验法。结果 :2 8例SARS冠状病毒感染者血清IL 8水平、病程第 2周IL 12水平比正常健康对照组明显降低 (P <0 0 5 )。SARS冠状病毒感染者血清TGF β1水平与对照组比较无明显差异 (P >0 0 5 )。 结论 :IL 8和IL 12在SARS冠状病毒的致病与免疫过程中可能起降低细胞免疫功能作用     

The VO2 response to exhaustive square wave exercise: influence of exercise intensity and mode

We investigated the oxygen uptake (O₂) response to exhaustive square wave exercise of approximately 2, 5 and 8 min duration in cycling and running. Nine males completed a ramp test and three square wave tests on a motorised treadmill and the same four tests on a cycle ergometer, throughout which gas exchange was assessed (Douglas bag method). The peak O₂ from the ramp test was higher for running than for cycling [mean (SD): 58.4 (2.8) vs. 55.9 (3.7) ml.kg^–1.min^–1; P=0.04]. However O_2max (defined as the highest O₂ achieved in any of the four tests) did not differ between running and cycling [60.0 (2.9) vs. 58.5 (3.3) ml.kg^–1.min^–1; P=0.15]. The peak O₂ was similar (P>0.1) for the 5 and 8 min square wave tests [98.5 (1.8) and 99.2 (2.3) %O_2max for running; 97.0 (4.2) and 97.5 (2.0) %O_2max for cycling] but lower (P<0.001) for the 2-min test [91.8 (2.5) and 89.9 (5.5) %O_2max for running and cycling respectively]. O₂ increased over the final two 30-s collection periods of the 2-min test for cycling [O₂=0.18 (0.15) l.min^–1; P<0.01] but not running [O₂=0.00 (0.09) l.min^–1; P=0.98]. We conclude that in the aerobically fit the peak O₂ for square wave running or cycling at an intensity severe enough to result in exhaustion in approximately 2 min is below O_2max. In running, O₂ plateaus at this sub-maximal rate.