Rapid destruction of newly synthesized excess beta-globin chains in HbH disease

A subject with HbG Philadelphia-HbH disease exhibited an unusually high alpha/beta synthesis ratio; when peripheral blood was tested in vitro on several occasions, ratios of 0.63 - 0.89 were obtained after incubations of 30-120 min. HbH amounted to 5%-8% of the circulating hemoglobin. Rapid destruction of excess newly synthesized beta-globin was demonstrated in kinetic and pulse-chase experiments. After 2 min of incubation, the alpha/beta synthesis ratio was 0.48; this figure rose to 0.89 by 30 min. The zero time alpha/beta ratio was estimated to be 0.35. The degradation of beta-chains was calculated to proceed at approximately one-half the rate of beta-globin synthesis; this result was confirmed by the loss of 50% of the specific activity in beta- chains during 9 min of a chase experiment following a 10-min radioactive pulse. The results suggest that efficient proteolysis may be responsible, in some blacks, for the low levels of excess beta- globin chains in HbH disease as well as for the mildness of the clinical disorder.     

Spirometry utilization for COPD: how do we measure up?

BACKGROUND: COPD is a significant cause of morbidity and mortality. Guidelines recommend the confirmation of a COPD diagnosis with spirometry. Limited evidence exists, however, documenting the frequency of spirometry use in clinical practice. METHODS: The National Committee for Quality Assurance recruited five health plans to determine the proportion of patients >/= 40 years old with a new diagnosis of COPD who had received spirometry during the interval starting 720 days prior to diagnosis and ending 180 days after diagnosis. Patients were identified via International Classification of Diseases, Ninth Revision diagnostic codes for encounters during the period July 1, 2002, through June 30, 2003. For each patient, the participating plans provided patient demographic and claims data from administrative data systems. RESULTS: Participating health plans covered 1,597,749 members with a total of 5,039 eligible COPD patients identified. Patients in the 40 to 64 age range had the highest percentage of new COPD diagnoses. Women were also slightly more likely to undergo spirometry (33.5% vs 29.4%, p = 0.001). Approximately 32% of patients with a new diagnosis of COPD had undergone spirometry in the specified interval. Spirometry frequency was lowest in older patients, with the lowest frequency in those >/= 75 years old. CONCLUSIONS: Our study suggests that approximately 32% of a broad range of patients with a new COPD diagnosis had undergone spirometry within the previous 2 years to 6 months following diagnosis. In addition, spirometric testing appeared to decrease with increasing age. As opposed to a prior report, women were not less likely to have undergone spirometry. This study shows that spirometry is infrequently used in clinical practice for diagnosis of COPD and suggests opportunities for practice improvement.     

Eyebrow anomalies as a diagnostic sign of genomic disorders

Silengo M, Belligni E, Molinatto C, Baldassare G, Biamino E, Chiesa N, Zuffardi O, Girirajan S, Eichler EE, Ferrero GB. Eyebrow anomalies as a diagnostic sign of genomic disorders. Microdeletions and microduplications in the human genome, termed genomic disorders, contribute to a high proportion of human multisystemic neurodevelopmental diseases and are detected by array‐based comparative genomic hybridization (aCGH). In general, most genomic disorders are associated with craniofacial and skeletal features and behavioural abnormalities, in addition to learning disability and developmental delay (LD/DD). Specifically, recognition of a characteristic ‘acial gestalt’ has been the key to distinguish one genomic disorder from the other. Here, we report our experience concerning the relevance of abnormal eyebrow pattern as a diagnostic indicator of specific genomic disorders.     

LEARN 2 MOVE 0-2 years: effects of a new intervention program in infants at very high risk for cerebral palsy; a randomized controlled trial

Background

Bronchiolitis is the most common reason for admission of infants to hospital in developed countries. Fluid replacement therapy is required in about 30% of children admitted with bronchiolitis. There are currently two techniques of fluid replacement therapy that are used with the same frequency-intravenous (IV) or nasogastric (NG). The evidence to determine the optimum route of hydration therapy for infants with bronchiolitis is inadequate. This randomised trial will be the first to provide good quality evidence of whether nasogastric rehydration (NGR) offers benefits over intravenous rehydration (IVR) using the clinically relevant continuous outcome measure of duration of hospital admission.

Methods/Design

A prospective randomised multi-centre trial in Australia and New Zealand where children between 2 and 12 months of age with bronchiolitis, needing non oral fluid replacement, are randomised to receive either intravenous (IV) or nasogastric (NG) rehydration. 750 patients admitted to participating hospitals will be recruited, and will be followed daily during the admission and by telephone 1 week after discharge. Patients with chronic respiratory, cardiac, or neurological disease; choanal atresia; needing IV fluid resuscitation; needing an IV for other reasons, and those requiring CPAP or ventilation are excluded. The primary endpoint is duration of hospital admission. Secondary outcomes are complications, need for ICU admission, parental satisfaction, and an economic evaluation. Results will be analysed using t-test for continuous data, and chi squared for categorical data. Non parametric data will be log transformed.

Discussion

This trial will define the role of NGR and IVR in bronchiolitis

Trail registration

The trial is registered with the Australian and New Zealand Clinical Trials Registry - ACTRN12605000033640     

电磁辐射后小胶质细胞活化状态和分泌功能的变化

目的:一定量的电磁辐射可引起中枢神经系统神经元的损伤,但其对小胶质细胞的影响尚不清楚。实验观察电磁辐射对小胶质细胞活化状态以及分泌功能的影响,揭示电磁辐射对小胶质细胞及中枢神经损伤的效应关系。方法:实验于2006-08/2007-05在解放军第三军医大学电磁辐射医学防护教育部重点实验室完成。取体外培养的N9小胶质细胞接受X波段脉冲波,平均功率密度为90mW/cm2的电磁波,一次性照射20min,在辐照后0,1,3,6,12,24h等6个时相点观察活化的N9细胞形态学,采用免疫组化的方法观察OX-42的表达情况,用酶联兔疫吸附测定方法检测N9细胞培养上清液中肿瘤坏死因子α的水平,采用硝酸还原酶法检测培养上清液中NO浓度。以未接受电磁波辐照的N9小胶质细胞为假辐照组进行对照。结果:①电磁辐射后3hN9小胶质细胞OX-42表达开始明显增强,并一直持续到辐照后24h,细胞形态由静息状态转变为激活状态;②NO的浓度在辐照后1h开始升高(P<0.05),到辐照后6h达到峰值(P<0.01),12h后趋于恢复,24h后再次明显升高(P<0.05)。③肿瘤坏死因子α水平辐照3h后显著升高(P<0.01),并一直持续到12h,到辐射后24h又再次升高,并达到峰值(P<0.01)。结论:电磁辐射辐照可明显诱导小胶质细胞激活,活化后的小胶质细胞分泌NO、肿瘤坏死因子α等细胞因子的功能增强,分泌大量细胞因子反馈调节引起辐射后期的小胶质细胞激活。     

Progesterone stimulates p42 extracellular signal-regulated kinase (p42erk) in human spermatozoa

Mitogen-activated protein kinases (MAPK), also known as extracellular signal-regulated kinases (ERKs) are cytoplasmic and nuclear serine/threonine kinases involved in signal transduction of several extracellular effectors. Recently, we have demonstrated that ERKs are present in spermatozoa and are involved in the regulation of the process of capacitation. We report here the effect of progesterone, a well-known inducer of the acrosome reaction in mammalian spermatozoa, on the immunolocalization, phosphorylation and activity of ERKs in capacitated human spermatozoa. We demonstrated that short-term incubation of spermatozoa with progesterone induces phosphorylation and activation of ERKs, resulting in redistribution of the proteins from the post-acrosomal region to the equatorial segment within the sperm head. To investigate the role of ERKs on the biological effects of progesterone, we used the MAPK cascade inhibitor PD098059, which strongly inhibited progesterone-induced activation of ERK-2. This compound did not inhibit progesterone-induced acrosome reaction, although it prevented redistribution of the enzyme to the equatorial region of the sperm head. These results suggest that the two processes, although temporally related, are independent. In conclusion, we provide new insight into the signal transduction pathways involved in the non- genomic action of progesterone in spermatozoa and suggest a possible involvement of ERKs in the process of fertilization.