胰腺癌中ERα变异体的表达

目的检测胰腺癌中雌激素受体α(ERα)不同变异体ERC4、ERD3、ERD5mRNA的表达。方法采用免疫组化和RT-PCR检测技术,对50例胰腺癌和20例乳腺癌患者ERα的表达以及变异体ERC4、ERD3、ERD5mRNA的表达进行检测。结果胰腺癌ERα蛋白的阳性率为32％。ERD3mRNA在ER阳性胰腺癌表达低于阴性病例;ERC4mRNA在ER阴性胰腺癌表达明显低于阳性病例(P<0.05);ERD5mRNA在ER阳性胰腺癌表达低于阴性病例。结论ERα变异体的检出说明它们在胰腺癌发生过程中起一定的作用。在胰腺癌的发生过程中,ERα变异体mRNA的表达失控。     

Evidence that calpains and elastase do not produce the von Willebrand factor fragments present in normal plasma and IIA von Willebrand disease

Recent evidence suggests that proteolysis plays an important role in some forms of inherited and acquired von Willebrand disease (vWD). Because calpains and one or more enzymes released from polymorphonuclear leukocytes are known to proteolyze von Willebrand factor (vWF) in vitro with resultant loss of large multimers similar to that seen in IIA vWD, they have been suggested as being responsible for the proteolysis in vivo. Using monoclonal epitope mapping, we have examined the proteolysis of the vWF subunit by porcine calcium- activated neutral proteases (calpains) and human leukocyte elastase to determine whether they produce the vWF proteolytic cleavage products seen in normal individuals and IIA vWD. Purified vWF was digested with porcine calpains I and II. We found no difference in the size, location, and quantity of the fragments produced by calpain I v calpain II. New fragments were detected of approximately 200, 170, 150, and 125 Kd. There was no evidence for generation of the native 140 and 176 Kd fragments. Some loss of the native fragments was seen, which suggests that they were further cleaved. Epitope mapping of the 170- and 150-Kd calpain-cleaved fragments revealed them to be from different parts of the molecule than the regions from which the native 176- and 140-Kd fragments derived. This was further supported by determination of the amino-terminal sequence of the calpain-cleaved 170- and 150-Kd fragments. Digestion of vWF with human leukocyte elastase produced new fragments at 210/205, 190, 170/165, 145/140, and 130/125 Kd. No generation of native fragments was detected. Monoclonal epitope mapping of the 145/140-Kd elastase-cleaved band proved that it derived from the carboxyl-terminal portion of the vWF molecule, whereas the native 140- Kd fragment is derived from the amino-terminal end. Neither calpains nor human leukocyte elastase produced the proteolyzed fragments present in normal and IIA vWD and, therefore, probably do not cause the loss of large multimers that is seen in that disorder.     

Effect of cell concentration on bone marrow and peripheral blood stem cell cryopreservation

The effects of cell concentration during cryopreservation on bone marrow (BM) or peripheral blood (PB)-derived hematopoietic progenitor cells have not been described. The much greater numbers of cells harvested for autologous PB stem cell (PBSC) transplantation requires that the cells be frozen at higher cell concentrations, or in much greater volumes, compared with BM. We cryopreserved 108 PBSC collections from 30 patients at an average (+/- SD) cell concentration of 3.7 +/- 1.9 x 10(8) nucleated cells per mL in 127 +/- 45 mL. The proportion of mononuclear cells was 52.9% +/- 27.2%. The products also contained 2.9 +/- 2.1 x 10(9) platelets/mL and an average red cell proportion of 12.9% +/- 7.2%. The nucleated cell recovery after thawing was 75.4% +/- 13.0%. The nucleated cell concentration during freezing was not predictive for the postthaw recoveries of nucleated cells (P = .38), granulocyte-macrophage colony-forming unit (P = .06) or CD34+ cells (P = .54), or for the viability of mononuclear cells (P = .81). The platelet and red cell concentrations similarly were not predictive for these endpoints. Samples (3 BM, 7 PBSC) from 10 patients were simultaneously cryopreserved at two-fold, and from 5 additional patients (PBSC) at 6- to 24-fold differing cell concentrations. A lower recovery of erythroid burst forming unit was found for samples frozen at higher cell concentrations (P = .04), but no significant differences were found in the other endpoints listed above. The average cell concentration during freezing for each patient's PBSC collections (n = 34 patients) did not predict time to achieve a PB count of > 500 granulocytes/microL (P = .51) or platelet transfusion independence (P = .39). Patients achieved these endpoints of engraftment at medians of 12 and 13 days, respectively. The infusion of these products was generally well tolerated. Similarly, the cell concentration at which BM cells were frozen did not predict for the duration of granulocyte (P = .63) or platelet (P = .36) aplasias for 54 patients undergoing autologous BM transplantation. These data suggest that PBSC or BM cells collected for transplantation may be cryopreserved at very high cell concentrations without loss of engraftment potential or undue infusion-related toxicity.     

Premature chromosome condensation studies in human leukemia: 5. Prediction of early relapse

Previous reports have suggested that the technique of premature chromosome condensation (PCC) is useful for predicting relapse in patients with acute leukemia. However, these studies involved patients had been in complete remission (CR) for various periods of time and had heterogeneous expectations for relapse. The purpose of this study was to further determine the value of PCC in predicting relapse by examining the PCC characteristics of bone marrow specimens from patients with acute leukemia on a common therapeutic regimen after similar periods in CR. The remission durations after the PCC determinations were compared between patients with high or low proliferative potential indices (PPI, or the fraction of G1 cells in late G1 phase). Of 60 patients studied between two and eight weeks after achieving CR, 14 of the 16 patients exhibiting high PPI values (greater than or equal to 35) have relapsed. The mean time from PCC measurement to relapse was 23 weeks. In contrast, only 19 of the 44 patients exhibiting low PPI values have relapsed, with an estimated mean time to relapse of 68+ weeks. Likewise, of 38 patients studied between nine and 15 weeks of CR, nine of the ten patients exhibiting high PPI values have relapsed (mean time to relapse, 23 weeks), while only 16 of 28 patients with low PPI values have relapsed (estimated mean time to relapse, 54+ weeks). The predictive value of the PCC technique was found to be independent of other prognostic factors for the duration of CR, and it identified those patients within the poor prognostic category with a high likelihood of imminent relapse. While similar trends were observed at later time intervals in CR, the differences in relapse rate between patients with high or low PPI values is not significant. These results confirm the usefulness of the PCC technique in predicting relapse in acute leukemia and could aid in the identification of patients who might benefit by an alteration of therapeutic strategy.     

Protein co-isolated with human tissue factor impairs recovery of activity

Preparations of human tissue factor isolated by immunoaffinity chromatography contain variable amounts of 47,000 mol wt, 55,000 mol wt, and multimeric tissue factor when analyzed without reduction on polyacrylamide gels in sodium dodecyl sulfate (SDS). When analyzed after reduction, the 47,000 mol wt tissue factor apoprotein and a protein of about 12,000 mol wt are observed. Elution of tissue factor from polyacrylamide gel slices, followed by reassociation with lipids, restored proportionately much greater tissue factor activity with the 47,000-mol wt protein than with the 55,000-mol wt form. Cyanogen bromide cleavage at the single tissue factor methionine revealed that the 12,000-mol wt protein is associated with the carboxyl-terminal peptide derived from the 47,000-mol wt protein. These results reveal that association of the 12,000-mol wt protein with the cytoplasmic domain of tissue factor can modulate its activity in vitro.     

Treatment of neonatal infections: a multi-country analysis of health system bottlenecks and potential solutions

Background

Around one-third of the world's 2.8 million neonatal deaths are caused by infections. Most of these deaths are preventable, but occur due to delays in care-seeking, and access to effective antibiotic treatment with supportive care. Understanding variation in health system bottlenecks to scale-up of case management of neonatal infections and identifying solutions is essential to reduce mortality, and also morbidity.

Methods

A standardised bottleneck analysis tool was applied in 12 countries in Africa and Asia as part of the development of the Every Newborn Action Plan. Country workshops involved technical experts to complete a survey tool, to grade health system "bottlenecks" hindering scale up of maternal-newborn intervention packages. Quantitative and qualitative methods were used to analyse the data, combined with literature review, to present priority bottlenecks and synthesise actions to improve case management of newborn infections.

Results

For neonatal infections, the health system building blocks most frequently graded as major or significant bottlenecks, irrespective of mortality context and geographical region, were health workforce (11 out of 12 countries), and community ownership and partnership (11 out of 12 countries). Lack of data to inform decision making, and limited funding to increase access to quality neonatal care were also major challenges.

Conclusions

Rapid recognition of possible serious bacterial infection and access to care is essential. Inpatient hospital care remains the first line of treatment for neonatal infections. In situations where referral is not possible, the use of simplified antibiotic regimens for outpatient management for non-critically ill young infants has recently been reported in large clinical trials; WHO is developing a guideline to treat this group of young infants. Improving quality of care through more investment in the health workforce at all levels of care is critical, in addition to ensuring development and dissemination of national guidelines. Improved information systems are needed to track coverage and adequately manage drug supply logistics for improved health outcomes. It is important to increase community ownership and partnership, for example through involvement of community groups.

     

Inpatient care of small and sick newborns: a multi-country analysis of health system bottlenecks and potential solutions

Background

Preterm birth is the leading cause of child death worldwide. Small and sick newborns require timely, high-quality inpatient care to survive. This includes provision of warmth, feeding support, safe oxygen therapy and effective phototherapy with prevention and treatment of infections. Inpatient care for newborns requires dedicated ward space, staffed by health workers with specialist training and skills. Many of the estimated 2.8 million newborns that die every year do not have access to such specialised care.

Methods

The bottleneck analysis tool was applied in 12 countries in Africa and Asia as part of the Every Newborn Action Plan process. Country workshops involved technical experts to complete the survey tool, which is designed to synthesise and grade health system "bottlenecks" (or factors that hinder the scale up) of maternal-newborn intervention packages. For this paper, we used quantitative and qualitative methods to analyse the bottleneck data, and combined these with literature review, to present priority bottlenecks and actions relevant to different health system building blocks for inpatient care of small and sick newborns.

Results

Inpatient care of small and sick newborns is an intervention package highlighted by all country workshop participants as having critical health system challenges. Health system building blocks with the highest graded (significant or major) bottlenecks were health workforce (10 out of 12 countries) and health financing (10 out of 12 countries), followed by community ownership and partnership (9 out of 12 countries). Priority actions based on solution themes for these bottlenecks are discussed.

Conclusions

Whilst major bottlenecks to the scale-up of quality inpatient newborn care are present, effective solutions exist. For all countries included, there is a critical need for a neonatal nursing cadre. Small and sick newborns require increased, sustained funding with specific insurance schemes to cover inpatient care and avoid catastrophic out-of-pocket payments. Core competencies, by level of care, should be defined for monitoring of newborn inpatient care, as with emergency obstetric care. Rather than fatalism that small and sick newborns will die, community interventions need to create demand for accessible, high-quality, family-centred inpatient care, including kangaroo mother care, so that every newborn can survive and thrive.

     

Proteolytic degradation of von Willebrand factor after DDAVP administration in normal individuals

The infusion of 1-deamino-8-D-arginine vasopressin (DDAVP) in normal individuals is followed by an increase in factor VIII/von Willebrand factor (vWF) in plasma, by an increase in intensity of all sizes of multimers, and by the appearance of larger multimers of vWF than those seen in the resting state. Since the larger multimers are rapidly cleared and proteolysis is known to cause disaggregation of large multimers, we evaluated the degree of vWF proteolysis after DDAVP administration. DDAVP was infused into eight normal adult volunteers, and the relative proportions of the intact 225 kilodalton (kDa) subunit and the 189, 176, and 140 kDa vWF fragments were compared before and at different times after DDAVP infusion. The relative proportion of the 176 kDa fragment was increased, whereas that of the other species was decreased, thereby indicating that proteolytic fragmentation had occurred. However, plasmin did not appear to be responsible because the vWF fragments characteristically produced by this enzyme could not be detected. Concomitant analysis of vWF multimeric structure showed that these changes were accompanied by an increase in the relative proportion of the satellite bands, which suggests that they were proteolytically generated. Proteolysis may explain, at least in part, rapid clearance of larger vWF multimers released by DDAVP.