抑制素βa亚基片段的合成及活性的初步测定

以固相多肽合成方法合成了抑制素β_a亚基的六个片段:Ⅰb-βA(37～39)-NH₂(Ⅰ),Ⅰb-βA(34～39)-NH₂(Ⅱ),Ⅰb-β_A(30～39)-NH₂(Ⅲ),Ⅰb-β_A(23～39)-NH₂(Ⅳ),Ⅰb-β_A(16～39)-NH₂(Ⅴ)和Ⅰb-β_A(14-39)-NH₂(Ⅵ),对产物进行了分离纯化。用垂体细胞培养方法对其中Ⅰ,Ⅱ和Ⅲ进行生物活性测定,表明它们不能抑制由LHRH诱导的FSH分泌,Ⅳ,Ⅴ和Ⅵ三个太肽片段由于难溶于中性介质,需要寻求其它方法对其进行生物活性测定。     

Thrombolytic Therapy Within One Hour of the Onset of Acute Myocardial Infarction

Between 1986 and 1988, 239 consecutive patients with acute myocardialinfarction received thrombolytic therapy up to 285 minutes afteronset of symptoms; in 39 (17 with anterior infarction, 21 inferior,one lateral infarction) recombinant tissue plasminogen activatoror anistreplase was administered a mean of 51 minutes (range20–60 minutes) after the onset of symptoms. The patencyrates (26 of 30; 87 per cent), rapid ST segment resolution (36of 38; 95 per cent) and QRS score of 3 (28 of 38; 74 per cent)were statistically significantly higher for those seen and treatedin the first hour in comparison with those seen and treatedlater. For those treated within the first hour mean peak creatine kinasewas 1264 U/I for those with TIMI grade 2 or 3 (partial or completeperfusion) compared with 3005 U/I for those with TIMI grade0 or 1 (no perfusion or penetration without perfusion) (p=0.02):mean peak creatine kinase-MB for those with TIMI grade 2 or3 perfusion was 115 U/I compared with 312 U/I for those withTIMI grade 0 or 1 (p=0.01). Four of the 39 patients developedventricular fibrillation following thrombolytic therapy, threewithin 24 hours of infarction and one following reinfarctionon day 15. There were no significant bleeding complications.One patient died. Thrombolytic therapy within 1 hour of the onset of symptomsled to a very high angiographic patency rate, rapid ST segmentresolution with preservation of left ventricular function. Thistherapy is without significant complications.     

Blood transfusion costs: a multicenter study

The cost of delivering a unit of blood (whole blood or red cells) to a hospitalized patient was examined in 19 United States teaching hospitals. The average hospital acquisition cost was calculated by using the prices charged by regional blood centers for blood products. To this cost was added an estimate of costs incurred by hospitals for handling, testing, and administering blood. Across study sites, the average hospital cost per unit transfused was $155 and the average charge to the patient was $219. Acquisition cost, the price that hospitals pay for blood, was 37 percent of the total cost to the hospital; the other 63 percent of the hospital cost included costs for blood bank handling (13%), laboratory tests (43%), and blood administration (7%). Significant variations in blood transfusion cost were found within our sample. Most of the variability can be attributed to geographic location of the blood supply source, type of red cell product transfused, prices charged by blood transfusion services, and the frequency of laboratory tests. The results of this transfusion cost study may be helpful in determining the costs of health care delivery, especially when blood transfusions are indicated.     

Apoptosis and resolution of experimental renal infective tubulointerstitial nephritis

Summary: Resolution of tubulointerstitial nephritis represents an important step in limiting renal fibrogenesis. However, the mechanism of this resolution remains poorly understood. to determine if apoptosis has a role in this process, we studied its incidence in an experimental model of renal infection and scarring, induced by direct inoculation of Escherichia coli into the renal cortex of Sprague-Dawley rats. the focal lesion produced was studied in animals killed at various time points up to 100 days post inoculation. Apoptosis was identified by electron microscopy (EM) and in-situ labelling of fragmented DNA using terminal transferasemediated deoxy-uridine-5'-triphospate (UTP) nick end labelling (TUNEL). Results were compared with morphological assessment of tubulointerstitial cellularity and macrophage localization. Terminal transferasemediated UTP nick end labelling localized apoptosis to interstitial cells, tubular casts and occasional tubular epithelia and double labelling demonstrated apoptotic body incorporation in macrophages. Interstitial cellularity was maximum at day 3, decreasing significantly by 100 days ( P < 0.01). the incidence of interstitial apoptosis was increased by 3 days and remained significantly higher than day 0 controls throughout ( P < 0.05). Tubular cellularity was significantly less than in control animals throughout the experimental time period. Although the rate of tubular apoptosis was increased, this difference was not statistically significant. In conclusion, apoptosis may represent an important mechanism in the reduction of tubulointerstitial cellularity after experimental renal infection. This in turn, may be important in limiting subsequent interstitial scarring.     

Use of tocolytics: what is the benefit of gaining 48 hours for the fetus?

Preterm birth remains one of the serious problems in perinatal medicine and is associated with an increased risk of neonatal complications and long-term morbidity. Although each day that delivery is delayed between 22 and 28 weeks of gestation increases survival by 3%, since most spontaneous preterm labour occurs between 28 and 34 weeks of gestation, this is of secondary concern; the primary goal of delay is to improve the function of certain systems in the fetus and to balance the risks of a hostile intrauterine environment with the complications of extrauterine preterm life. Although there is a lack of definitive evidence that tocolytic drugs improve outcome following spontaneous preterm labour and preterm birth, there is ample evidence that tocolysis delays delivery for long enough to permit administration of a complete course of antepartum glucocorticoids and to facilitate in utero transfer to a tertiary care unit where neonatal care will be optimal. Both these measures have been associated with improved outcomes; antepartum glucocorticoids reduce the incidence of respiratory distress syndrome, intraventricular haemorrhage, periventricular leucomalacia and necrotising enterocolitis, and in utero transfer is associated with decreased morbidity and mortality and less hospital-based intervention compared with postnatal transportation. Consequently, women who are more likely to benefit from tocolysis are those at early gestational ages, those needing transfer to a hospital that can provide neonatal intensive care and those who have not yet received a full course of antepartum glucocorticosteroids. In these cases, delaying labour for at least 48 hours with drugs such as atosiban should be considered, since it offers clear advantages for the fetus.     

Altered white matter diffusion anisotropy in normal and preterm infants at term‐equivalent age

To investigate white matter (WM) development, voxelwise analyses of diffusion tensor MRI (DTMRI) data, acquired from 12 very preterm and 11 preterm infants with gestational ages (GA) ranging from 25 to 29 and 29 to 32 weeks, respectively, and 10 newborn normal term infants were performed. T₂ relaxation measures were also generated to assess brain water content. Compared with newborn term infants, very preterm infants were found to possess reduced fractional anisotropy (FA) within the frontal lobe, and a number of anterior and posterior commissural pathways. Preterm infants possessed reduced FA mainly within the posterior regions of the corpus callosum. Unexpectedly, we observed significantly reduced FA and increased T₂ within a number of corticospinal projections in the newborn term infants compared to the preterm groups. This finding may reflect increased water concentration and/or a lowering of FA due to the presence of crossing interhemispheric WM projections. These findings indicate that care should be taken when interpreting FA indices without knowledge of the possible effects of water concentration in the newborn infant brain. Magn Reson Med 60:761–767, 2008. © 2008 Wiley‐Liss, Inc.     

Migration and lymphatic spread of calcified paraffinomas after breast augmentation

A 62 year old Chinese woman presented 25 years after having both breasts augmented with paraffin injections. Development of paraffinomas and multiple episodes of paraffin-related mastitis eventually resulted in bilateral mastectomies. The unusual distribution of migrated calcified paraffinomas in the thoracic wall and its lymphatic system is documented on computed tomography.     

Immunodeficiency and infantile bone and joint infection

Fifteen patients with infantile bone and joint infections were studied immunologically and clinically, 3 at the time of illness and 12 later. Abnormality of immunoglobulins, or complement, or phagocytes was found in 9 patients; 6 were within normal limits for the tests undertaken. Immunodeficiency is probably responsible for the subdued clinical signs of infection and for delayed diagnosis in some patients. It was also related to the extent of femoral head damage in infective arthritis of the hip and to the incidence of wound infection in late elective surgery.