Expression of blood group A antigens in human bone marrow cells

We have studied the appearance of blood group A-activity during hematopoiesis in human bone marrow cells by the use of the blood group A-specific lectin from Vicia cracca. Cells that bound the lectin were identified using antiserum against the lectin followed by rosetting with protein A-containing Staphylococcus aureus cells. Only cells of the erythroid lineage from blood group A individuals formed staphylococcal rosettes. A-activity occurred in basophilic normoblasts and later stages of erythropoiesis, whereas pronormoblasts were negative. The appearance of blood group A-activity coincided roughly with the onset of hemoglobin synthesis and slightly later than the expression of the major sialoglycoprotein of erythrocytes, glycophorin A. Glycophorin A did not, however, contain blood group A-activity when analyzed by immunoprecipitation and gel electrophoresis.     

大剂量富马酸奎的平中毒的急救

1病例报告患者,女,33岁,因患精神分裂症服富马酸奎的平5 mo,1 wk前服药不规律,出现幻觉,遂自服160片(0.1 g/片)3 h送县中医院抢救,查体与急救: 深昏迷,瞳孔散大约5 mm,血压波动于90～60/40～30 mmHg(12～8/5～4 kPa),全身不自主抽搐.     

The effects of up to 240 days of tacrolimus therapy on the gingival tissues of rats – a morphological evaluation

Background:  Tacrolimus, an immunosuppressive drug used in organ transplantation, has been reported not to induce gingival overgrowth. However, prevalence studies are limited, and the methods used for assessing gingival overgrowth varies among studies.
Objective:  The purpose of this study was to evaluate the effects of up to 240 days of tacrolimus therapy on gingival tissues of rats.
Materials and methods:  Rats were treated for 60, 120, 180 and 240 days with daily subcutaneous injections of 1 mg/kg body weight of tacrolimus. After histological processing, the oral and connective tissue, volume densities of fibroblasts ( V _f), collagen fibers ( V _cf) and other structures ( V _o) were assessed in the region of the lower first molar.
Results:  After 60 and 120 days of treatment with tacrolimus, gingival overgrowth was not observed. The gingival epithelium, connective tissue, as well as the values for V _f, V _cf, and V _o were similar to those of the control rats ( P  > 0.05). After 180 and 240 days of the treatment, gingival overgrowth was associated with a significant increase in the gingival epithelium and connective tissue as well as an increase in the V _f and V _cf ( P  < 0.05).
Conclusions:  Within the limits of the experimental study, it may be concluded that the deleterious side effects of tacrolimus on the gingival tissues of rats may be time-related.     

Retention of cast crown copings cemented to implant abutments

Background: The cementation of crowns to dental implant abutments is an accepted form of crown retention that requires consideration of the properties of available cements within the applied clinical context. Dental luting agents are exposed to a number of stressors that may reduce crown retention in vivo, not the least of which is occlusal loading. This study investigated the influence of compressive cyclic loading on the physical retention of cast crown copings cemented to implant abutments. Methods: Cast crown copings were cemented to Straumann synOcta titanium implant abutments with three different readily used and available cements. Specimens were placed in a humidifier, thermocycled and subjected to one of four quantities of compressive cyclic loading. The uniaxial tensile force required to remove the cast crown copings was then recorded. Results: The mean retention values for crown copings cemented with Panavia‐F cement were statistically significantly greater than both KetacCem and TempBond non‐eugenol cements at each compressive cyclic loading quantity. KetacCem and TempBond non‐eugenol cements produced relatively low mean retention values that were not statistically significantly different at each quantity of compressive cyclic loading. Compressive cyclic loading had a statistically significant effect on Panavia‐F specimens alone, but increased loading quantities produced no further statistically significant difference in mean retention. Conclusions: Within the limitations of the current in vitro conditions employed in this study, the retention of cast crown copings cemented to Straumann synOcta implant abutments with a resin, glass ionomer and temporary cement was significantly affected by cement type but not compressive cyclic loading. Resin cement is the cement of choice for the definitive non‐retrievable cementation of cast crown copings to Straumann synOcta implant abutments out of the three cements tested.     

Five-day storage of platelets in a non-diethylhexyl phthalate- plasticized container

A non-diethylhexyl phthalate (DEHP)-plasticized blood bag for 5-day storage of random-donor platelet concentrates has been developed. The plastic bag is composed of polyvinylchloride plastic with a butyryl trihexyl citrate plasticizer. The suitability of this plastic for the storage of platelet concentrates for use in clinical transfusion practice was evaluated. In vitro storage studies showed no significant differences at Day 5 for a series of in vitro assays (test plastic vs. control plastic) including pH (7.31 vs. 7.44), lactate dehydrogenase discharge (21.8 vs. 17.1%), pO2 (103 vs. 120 torr), osmotic recovery (52 vs. 57%), and morphology score (527 vs. 516). For paired radiolabeled recovery and survival data from autologous blood donors, results showed equivalence between the test plastic and two control plastics. A small but significant difference between test and control plastics in regard to survival was found by using a linear computer model, but not with a gamma function (multiple-hit) model. For paired transfusions to thrombocytopenic patients, the corrected count increments at 1 to 4 hours (test vs. control) were 13,534 versus 15,494 (p > 0.05, NS). Similar results were seen for corrected count increments determined at 12 to 24 hours. It can be concluded that platelets stored in the test plastic are acceptable for use in clinical practice.     

Lineage promiscuity in hemopoietic differentiation and leukemia

An increasing number of reports document instances in which individual leukemic cells coexpress markers normally believed to be restricted to a single lineage. This has been interpreted by McCulloch and colleagues as aberrant programming or lineage infidelity and contrasts with earlier suggestions that lineage fidelity of gene expression was usually maintained in leukemia. We argue that several examples of infidelity are suspect on technical grounds, whereas others are bona fide and require explanation, eg, partial rearrangements and expression of Ig heavy-chain and/or T cell receptor genes in inappropriate cells and terminal deoxynucleotidyl transferase in leukemic myeloblasts. Individual examples of truly aberrant gene expression may well occur in leukemia but with insufficient regularity to be of general significance. We suggest that verifiable and consistent examples of apparent lineage infidelity do not reflect genetic misprogramming but rather the existence of a transient phase of limited promiscuity of gene expression occurring in normal biopotential or multipotential progenitors and able to be preserved as a relic in leukemic blast cell populations that are in maturation arrest. This alternative explanation has interesting implications for mechanisms of hematopoietic differentiation and leads to some testable predictions.     

Thymus and mediastinal node involvement in childhood langerhans cell histiocytosis: Long‐term follow‐up from the French national cohort

Background

Mediastinal involvement (MI) in Langerhans cell histiocytosis (LCH) has been rarely reported. Here, we describe the clinical, radiological, and biological presentation, and the outcome of childhood LCH with MI.

Method

From the French LCH register, which includes 1,423 patients aged less than 18 years, we retrieved the medical charts of patients with mediastinal enlargement detected on chest X‐rays.

Results

Thirty‐seven patients were retrieved, including 18 males; median age of diagnosis was 0.7 years, and median follow‐up time was 6.2 years. The prevalence of MI varied with the age at diagnosis, ranging from 7% below 1 year old to less than 1% at >5 years. Thirteen cases (35%) were diagnosed because of MI‐related symptoms, including respiratory distress (N = 4), superior venous cava syndrome (N = 2), and/or cough and polypnea (N = 10). CT scans performed in 32 cases at diagnosis showed tracheal compression (N = 5), cava thrombosis (N = 2), and/or calcification (N = 16). All patients presented multi‐system disease at LCH diagnosis, and 35/37 were initially treated with vinblastine and corticosteroids. Death occurred in five cases, due to MI (N = 1) or hematological refractory involvement (N = 4). The overall 5‐year survival was 87.1%, and immunodeficiency was not detected as a sequel.

Conclusions

MI in LCH mainly occurs in young children, and diagnosis was based on CT showing thymus enlargement and calcifications. Pediatr Blood Cancer 2013;60:1759–1765. © 2013 Wiley Periodicals, Inc.     

Misdiagnosis of tuberculosis and the clinical relevance of non—tuberculous mycobacteria in Zambia

ObjectiveTo determine the accuracy of TB diagnosis of TB in Zambia in the era of increasing HIV prevalence.MethodsSputum of the clinically diagnosed TB cases was additionally subjected to liquid culture and molecular identification. This study distinguished between TB cases confirmed by positive Mycobacterium tuberculosis (M. tuberculosis) cultures and mycobacterial disease caused by non-tuberculous mycobacteria (NTM).ResultsOnly 49% of the 173 presumptively diagnosed TB cases was M. tuberculosis cultured, while in 13% (22) cases, a combination of M. tuberculosis and NTM was found. In 18% of the patients only NTM were cultured. In 28%, no mycobacteria was cultivable. HIV positive status was correlated with the isolation of NTM (P <0.05).ConclusionsThe diagnosis of tuberculosis based on symptoms, sputum smear and/or chest X-ray leads to significant numbers of false-positive TB cases in Zambia, most likely due to the increased prevalence of HIV. The role of NTM in tuberculosis-like disease also seems relevant to the false diagnosis of TB in Zambia.     

妊娠诱发先天异常输尿管结石梗阻1例

1病例报告女,26岁.因孕5 mo余,右腰腹部间断性疼痛3 d伴高烧,于2004-05-27急诊入本院泌尿外科.患者疼痛难忍,向右下腹放射,间歇性,无恶心呕吐,无尿急、尿频、尿痛,伴发热,体温最高可达40℃,既往无泌尿系患病史.查体: T 40℃,P 110次/min,BP 16/10 kPa,R 21次/min.痛苦面容,心肺正常,右肾区及右输尿管走行区扣击痛.