Low-temperature storage of bone marrow in nitrogen vapor-phase refrigerators: decreased temperature gradients with an aluminum racking system

Large temperature gradients may exist in nitrogen vapor-phase refrigerators. Cryopreserved cells stored at higher levels may be considerably warmer than those stored closer to the liquid nitrogen reservoir. To decrease this temperature gradient, racking systems constructed of aluminum were placed in marrow storage refrigerators. The higher heat conductivity of aluminum resulted in a vapor-phase temperature gradient of only 5.9 degrees C at 22.5 inches above the liquid, as compared to the gradient of 86 degrees C seen with steel frames in a similar refrigerator. Temperature fluxes were minimal with lid opening or nitrogen filling. The thicker frame size and loss of the lowest storage level resulted in a storage capacity 63 percent of that achievable with steel frames and liquid immersion. Consumption of nitrogen was estimated to be 174 to 220 percent of the static usage in this model of refrigerator with 6 inches of nitrogen, but comparable to the consumption expected with full immersion of the racking system, regardless of frame construction. These data demonstrate the feasibility of achieving very low, stable, cryogenic temperatures in a vapor-phase refrigerator.     

Clostridium difficile after haemolytic uraemic syndrome

Six children are described who developed diarrhoea associated with Clostridium difficile during the course of haemolytic uraemic syndrome. The significance of this infection is discussed within the context of the pathophysiology of haemolytic uraemic syndrome.     

A study of the knowledge and attitude towards pulse polio immunization in semi urban areas of South India

Background

The government of India launched the pulse polio immunization (PPI) programme in 1995 with the aim of eradicating poliomyelitis by the end of 2000. Despite this, 733 children with polio were reported in 2009 alone. Therefore, there is a need to understand the reason underlying such high numbers of cases after so many years of programme implementation. This study was performed to assess the knowledge of the general population about poliomyelitis and PPI and their attitude and practice towards PPI.

Method

This cross-sectional study was undertaken in two semi- urban areas of Mangalore city. Only houses in which children under five lived were included in the study. Data was collected by interviewing any adult member of the household using a pretested questionnaire.

Results

The literacy rate of study participants was 99%. Only 35(10.9%) participants knew the correct mode of transmission of polio. More than one quarter of the study population were under the misconception that polio is a curable disease. The primary source of information about PPI in majority of participants was the television (n = 192; 60%). Two-hundred and eighty eight (90%) participants knew that the purpose of PPI was to eradicate polio. Only 128 (40%) participants knew that polio drops can be given to children with mild illnesses and an identical number of participants knew that hot food stuff should not be given for at least half an hour following vaccination administration. Misconceptions such as PPI causing vaccine overdose was identified among 7 (2.2%) participants, it is a substitute for routine immunization was believed among 30 (9.4%) participants and that oral polio vaccine prevents other diseases was seen among 76 (23.7%) participants. The educational status of the participants was significantly associated with their awareness level (χ² =13.668, DF=6, P=0.033).

Conclusion

This study identified a few important misconceptions associated with polio and PPI which need to be addressed by large scale awareness campaigns in order to achieve polio eradication in the near future.     

Identification of platelet proteins that bind alloantibodies and autoantibodies

We have used the techniques of radioimmunoprecipitation (RIP) and Western blot to identify the membrane proteins that bind certain alloantibodies. Anti-PlA1 sera precipitated two bands, corresponding to platelet glycoproteins IIb and III, whether or not calcium was present during the procedure. By Western blot, this antibody bound only glycoprotein III. Anti-PlA1 serum does not precipitate proteins from the platelets of a patient with Glanzmann's thrombasthenia. Two monoclonal antibodies reacting with lymphocyte HLA antigens, as well as sera from highly allosensitized patients, precipitated bands of 38,500 and 13,500 daltons. These bands correspond to the molecular weights of the two subunits of the HLA antigen, as it has been described for other cell types. The patients' sera also precipitated a protein of 72,000 daltons from some platelets. The sera of two patients with quinidine- induced thrombocytopenia precipitated a 138,000-dalton band (glycoprotein Ib-alpha) in the presence of quinidine. The purified IgG antibody from one patient did not require other plasma factors to bind to platelets in the presence of quinidine, while purified antibody from a second patient required plasma factors other than, or in addition to von Willebrand factor. Although several sera from patients with idiopathic thrombocytopenic purpura (ITP) were tested, only one precipitated membrane proteins by the RIP method; this serum identified binding proteins corresponding to glycoproteins IIb and III.     

鼻咽癌切除术后患者血浆DNA的快速变化

摘要：目的监测鼻咽癌病人于肿瘤切除手术期间和术后,其血浆DNA浓度的变化,以了解血浆DNA在体内的动态变化情况。方法静脉抗凝血分离血浆,从血浆中提取DNA,用实时定量PCR方法分别测定手术前、后鼻咽癌病人血浆DNA的浓度。结果肿瘤手术初期,病人血浆DNA的浓度会快速升高,随后其水平会迅速下降,DNA在血浆中的半衰期为126min;当血浆DNA水平降到最低时,其水平又会再次升高,至2385：min后出现第二个峰值。结论癌症病人游离DNA可以极其迅速地从血循环中被清除,第二个峰值的水平可能对评估组织损伤严重程度具有一定的临床意义,此研究为进一步研究血浆肿瘤DNA在其他肿瘤中的变化奠定了基础。