Terminal differentiation of human promyelocytic leukemic cells in primary culture in response to retinoic acid

The recent finding that retinoic acid induces terminal granulocytic differentiation of the human promyelocytic leukemia cell line, HL-60, prompted an investigation of the sensitivity to this inducer of human myelocytic leukemia cells in primary suspension culture. Of the 21 leukemic specimens, only cells from the two patients with acute promyelocytic leukemia differentiated in response to retinoic acid. After an incubation period of 5--7 days in 1 microM retinoic acid, the cells from these two patients showed extensive morphological and functional maturation. Thus, because it appears that retinoic acid specifically induces granulocytic differentiation of leukemic promyelocytes, this compound may have therapeutic utility in the treatment of acute promyelocytic leukemia.     

Efficacy of various methods of confidential unit exclusion in identifying potentially infectious blood donations

To determine the efficacy of various methods of confidential unit exclusion (CUE) among donors at increased risk of HIV exposure, we surveyed AABB institutional members on their experience with 3 CUE methods: ballot or barcode, completed at the time of donation, and call-back, performed by the donor after leaving the donor center. From June 1985 to December 1987, 5,049,883 donations at 48 donor centers were evaluable for analysis. The results of this survey suggest that ballot and barcode methods of CUE are important adjuncts to other donor screening procedures in identifying potentially infectious units, and that both of these methods are superior to the call-back system of unit exclusion.     

4例体外受精的胎儿和新生儿发生免疫性血小板减少症的报告

新生儿免疫性血小板减少症(Neonatalalloimmunethrom-bocytopenia,NATP)发病原因是由于母体产生针对胎儿特异性血小板抗原的IgG抗体,并发生抗原抗体反应。胎儿特异性血小板抗原来自父亲。NATP发病率约为0.l%。NATP占新生儿血小板减少症的3%和重度血小板减少(血小板计数<50×109     

Invalidation of antiglobulin tests by a high thermal amplitude cryoglobulin

A multiply transfused patient was referred for evaluation of a transfusion reaction. The direct and indirect antiglobulin tests (DAT, IAT) for alloantibody were negative. However, IgG-coated control cells failed to agglutinate in the negative reactions, casting doubt on their validity. At 4 degrees C, the patient's serum exhibited a large cryoprecipitate (2.9 mg/mL), made up predominantly of an IgG kappa paraprotein and having trace amounts of IgM and C3. Clear serum separated at 37 degrees C became cloudy within 10 minutes at room temperature (RT); within 4 hours, approximately 60 percent of the total precipitable cryoprotein had precipitated. Red cells (RBCs) incubated in fresh serum that had cooled to RT or RBCs obtained from RT or refrigerated samples contained cryoprecipitate that sedimented with the RBCs during washing with RT saline. On resuspension, enough IgG cryoglobulin redissolved to neutralize completely the commercial anti-IgG reagents. If the patient's samples were maintained at 37 degrees C, cryoprecipitate did not form, and RBCs washed four times at 37 degrees C gave valid DAT and IAT reactions. The removal of all cryoprecipitate from the patient's serum by centrifugation after overnight incubation at 4 degrees C also made possible valid antibody screening and compatibility tests.     

Innervation of the cavernous body of the human efferent tear ducts and function in tear outflow mechanism

The lacrimal sac and nasolacrimal duct are surrounded by a wide cavernous system of veins and arteries comparable to a cavernous body. The present study aimed to demonstrate the ultrastructure of the nervous tissue and the localisation of neuropeptides involved in the innervation of the cavernous body, a topic not previously investigated. Different S‐100 protein antisera, neuronal markers (neuron‐specific enolase, anti‐200 kDa neurofilament), neuropeptides (substance P, neuropeptide Y, calcitonin gene‐related peptide, vasoactive intestinal polypeptide) and the neuronal enzyme tyrosine hydroxylase were used to demonstrate the distribution pattern of the nervous tissue. The ultrastructure of the innervating nerve fibres was also examined by means of standard transmission electron microscopy. The cavernous body contained specialised arteries and veins known as barrier arteries, capacitance veins, and throttle veins. Perivascularly, the tissue was rich in myelinated and unmyelinated nerve fibres in a plexus‐like network. Small seromucous glands found in the region of the fundus of the lacrimal sac were contacted by nerve fibres forming a plexus around their alveoli. Many nerve fibres were positive for S‐100 protein (S 100), neuron‐specific enolase (NSE), anti‐200 kDa neurofilament (RT 97), calcitonin gene‐related peptide (CGRP), substance P (SP), tyrosine hydroxylase (TH), and neuropeptide Y (NPY). Vasoactive intestinal polypeptide (VIP) immunoreactivity was only demonstrated adjacent to the seromucous glands. Both the density of nerve fibres as well as the presence of various neuropeptides emphasises the neural control of the cavernous body of the human efferent tear ducts. By means of this innervation, the specialised blood vessels permit regulation of blood flow by opening and closing the lumen of the lacrimal passage as effected by the engorgement and subsidence of the cavernous body, at the same time regulating tear outflow. Related functions such as a role in the occurrence of epiphora related to emotional responses are relevant. Moreover, malfunction in the innervation of the cavernous body may lead to disturbances in the tear outflow cycle, ocular congestion or total occlusion of the lacrimal passages.     

Knowledge about the research and ethics committee at Makerere University,Kampala

Background

All research involving human participants should be reviewed by a competent and independent institutional research and ethics committee. Research conducted at Makerere University College of Health Sciences should be subjected to a rigorous review process by the ethics committee in order to protect human participants'' interests, rights and welfare.

Objective

To evaluate researchers'' knowledge about the functions and ethical review process of the College of Health Sciences research and ethics committee.

Methods

A cross sectional study. 135 researchers consented to participate in the study, but 70 questionnaires were answered giving a 52% response.

Results

Age ranged between 30 to 61 years, majority of participants 30–39 years. Most of the respondents do agree that theREC functions include Protocol review 86%, protection of research participants 84.3%, and monitoring of ongoing research. During ethical review, the RECpays special attention to scientific design [79.7%] and ethical issues [75.3%], but less to the budget and literature review. More than 97% of the respondents believe that the REC is either average or very good, while 2.8% rank it below average.

Conclusion

Respondents knew the major functions of the committee including protection of the rights and welfare of research participants, protocol review and monitoring of on going research, and the elements of protocol review that are given more attention include ;scientific design and ethical issues. Overall performance of the REC was ranked as average by respondents. The committee should limit delays in approval and effectively handle all functions of the committee.