Frequent ongoing T-cell receptor rearrangements in childhood B- precursor acute lymphoblastic leukemia: implications for monitoring minimal residual disease

Crosslineage T-cell receptor delta (TCR delta) rearrangements are widely used as tumor markers for the follow up of minimal residual disease in childhood B-precursor acute lymphoblastic leukemia (ALL) by polymerase chain reaction (PCR). The major drawback of this approach is the risk of false-negative results due to clonal evolution. We investigated the stability of V delta 2D delta 3 rearrangements in a group of 56 childhood B-precursor ALL patients by PCR and Southern blot analysis. At the PCR level, V delta 2D delta 3-to-J alpha rearranged subclones (one pathway for secondary TCR delta recombination) were demonstrated in 85.2% of V delta 2D delta 3-positive patients tested, which showed that small subclones are present in the large majority of patients despite apparently monoclonal TCR delta Southern blot patterns. Sequence analysis of V delta 2D delta 3J alpha rearrangements showed a biased J alpha gene usage, with HAPO5 and J alpha F in 26 of 32 and 6 of 32 clones, respectively. Comparison of V delta 2D delta 3 rearrangement status between diagnosis and first relapse showed differences in seven of eight patients studied. In contrast, from first relapse onward, no clonal changes were observed in six patients studied. To investigate the occurrence of crosslineage TCR delta rearrangements in normal B and T cells, fluorescence-activated cell sorter-sorted peripheral blood CD19+/CD3- and CD19-/CD3+ cell populations from three healthy donors were analyzed. V delta 2D delta 3 rearrangements were detected at low frequencies in both B and T cells, which suggests that V delta 2-to-D delta 3 joining also occurs during normal B-cell differentiation. A model for crosslineage TCR delta rearrangements in B-precursor ALL is deduced that explains the observed clonal changes between diagnosis and relapse and is compatible with multistep leukemogenesis of B-precursor ALL.     

Spermicidal activity of chelated complexes of bis(cyclopentadienyl)vanadium(IV)

Transition metal complexes containing vanadium IV have been shown to modulate the cellular redox potential and catalyse the generation of reactive oxygen intermediates (ROI). Since sperm function is exquisitely susceptible to ROI, we examined the effects of stable chelate complexes of vanadocenes on human sperm motility. We synthesized seven structurally distinct chelate complexes of bis(cyclopentadienyl)vanadium(IV) with bidentate ligands [i.e. vanadocene acetylacetonato monotriflate (VDacac), vanadocene hexafluoro acetylacetonato monotriflate (VDHfacac), vanadocene N-phenyl benzohydroxamato monotriflate (VDPH), vanadocene acethydroxamato monotriflate (VDH), vanadocene catecholate (VDCAT), vanadocene bipyridino ditriflate (VDBPY), and vanadocene dithiocarbamate monotriflate (VDDTC)], and evaluated their spermicidal activity using computer-assisted sperm analysis (CASA; Hamilton-Thorne). All seven chelate complexes of vanadocene elicited potent spermicidal activity at micromolar concentrations (EC50 values: 3.9-106 microM) without affecting the sperm acrosome integrity. The catecholate and acetylacetonate complexes of vanadocene were the most active and the bipyridyl complex the least active with an order of efficacy VDCAT > VDacac > VDDTC > VDPH > VDH > VDHfacac > VDBPY. The spermicidal activity of chelate complexes of vanadocenes was rapid and irreversible since the treated spermatozoa underwent apoptosis, as determined by the flow cytometric analysis of mitochondrial membrane potential, surface annexin V binding assay, in-situ nick-end labelling of sperm nuclei, and confocal laser scanning microscopy. These results provide unprecedented evidence that chelate complexes of vanadocene with bidentate ligands have spermicidal and apoptosis inducing properties. These vanadocene complexes, especially VDacac, may be useful as contraceptive agents.      

Significance of the latissimus dorsi for shoulder instability. I. Variations in its anatomy around the humerus and scapula

In a cadaveric instability model that leaves all muscles intact initially, we studied anteroinferior glenohumeral dislocation behavior after section of the ligaments on the humeral side of the joint. In this study, the latissimus dorsi seemed to play a role when complete section did not result in a locked anteroinferior dislocation. We therefore initiated a study to test the hypothesis that the latissimus dorsi may, in certain circumstances, depending on variations in its anatomy, influence dislocation behavior. Here, in Part I, we present the results of the anatomic study of latissimus dorsi and its tendons. The anatomy of the latissimus dorsi pertaining to the scapula and humerus was studied in 100 cadaver specimens. The distance between the uppermost part of the tendon of both the latissimus dorsi and the teres major and the edge of the articular cartilage of the humeral head (tendon-cartilage distance, TCD) as well as the width and length of the tendons were measured. Furthermore, the relationship between latissimus dorsi and the inferior angle of the scapula was studied. The tendon of the latissimus dorsi inserted at a variable distance from the cartilage of the humeral head: the TCD ranged from 12.6 to 31.6 mm (mean 21.06 mm+/-5.11 mm). The latissimus dorsi can have muscular fibers arising from the inferior angle of the scapula (type 1 scapular connection, 43%). Alternatively, there may be only a few fibrous strands between the muscle and the scapula or there may be an intervening bursa (type 2 scapular connection, 57%). This variability in the morphology of the latissimus dorsi may be a factor explaining the differences observed in a study of humerus-based sequential cutting of the glenohumeral capsule. This possibility is explored in Part II of the study. The latissimus dorsi may also complete the tendinous protection of the humeral side of the capsule generally provided by the rotator cuff.     

Surgical treatment of metastases from thyroid cancer in the axial skeleton. A retrospective study of 18 cases

Between 1990 and 1997, 18 patients with a mean age of 55.5 years (11 females, 7 males) underwent surgical treatment for a metastasis from thyroid cancer involving the axial skeleton. At the time of surgery all patients had a poor prognosis: 7 metastases revealed the thyroid cancer, all 18 patients had a neurological or mechanical complication, 9 had multiple metastases, all were over 40 years of age. After arteriography with embolization, the surgical procedure consisted of curettage of the tumor and reconstruction, followed by treatment with iodine 131. The survival rate 3 years after surgery was 50%. At the last review, the functional outcome was good and 17 patients had total neurological recovery. Four complications occurred: 1 operative hemorrhage, 3 postoperative infections. Four patients had local recurrence of the metastasis with a one-year survival rate of 20%. When the thyroid cancer was revealed by the axial metastasis, the 3-year-survival rate was 42%. In cases with huge metastases, the 3-year-survival rate was 71%. It appears from these data that surgical treatment of metastases from thyroid cancer in the axial skeleton still achieves a good functional outcome even in cases where neurological or mechanical complications had occurred before surgery.     

Regulation of erythropoietin production in a human hepatoblastoma cell line

Production of immuno and biologically active erythropoietin was documented to occur in the human hepatoblastoma cell line HepG-2. The expression of the erythropoietin gene was further verified by Northern blot analysis using a single stranded RNA probe. In vitro studies showed that erythropoietin production by these cells was not stimulated by hypoxia or cobalt chloride, but was related to the proliferative activity of the cells in culture. In addition it was found that the secretion of erythropoietin was almost completely abrogated by tunicamycin, an inhibitor of N-linked glycosylation. This effect of tunicamycin was also observed in a permanently transfected cell line that secretes erythropoietin in large quantities.     

Comparing human and mouse salivary glands: A practice guide for salivary researchers

Mice are a widely utilized in vivo model for translational salivary gland research but must be used with caution. Specifically, mouse salivary glands are similar in many ways to human salivary glands (i.e., in terms of their anatomy, histology, and physiology) and are both readily available and relatively easy and affordable to maintain. However, there are some significant differences between the two organisms, and by extension, the salivary glands derived from them must be taken into account for translational studies. The current review details pertinent similarities and differences between human and mouse salivary glands and offers practical guidelines for using both for research purposes.     

Current cell models for bioengineering a salivary gland: a mini‐review of emerging technologies

Oral Diseases (2013) 19 , 236–244 Saliva plays a major role in maintaining oral health. Patients afflicted with a decrease in saliva secretion (symptomatically, xerostomia) exhibit difficulty in chewing and swallowing foods, tooth decay, periodontal disease, and microbial infections. Despite recent improvements in treating xerostomia (e.g., saliva stimulants, saliva substitutes, and gene therapy), there is a need of more scientific advancements that can be clinically applied toward restoration of compromised salivary gland function. Here we provide a summary of the current salivary cell models that have been used to advance restorative treatments via development of an artificial salivary gland. These models represent initial steps toward clinical and translational research, to facilitate creation of clinically safe salivary glands. Further studies in salivary cell lines and primary cells are necessary to improve survival rates, cell differentiation, and secretory function. Additionally, the characterization of salivary progenitor and stem cell markers are necessary. Although these models are not fully characterized, their improvement may lead to the construction of an artificial salivary gland that is in high demand for improving the quality of life of many patients suffering from salivary secretory dysfunction.     

Do number of days with low back pain and patterns of episodes of pain have similar outcomes in a biopsychosocial prediction model?

Purposes

We used two different methods to classify low back pain (LBP) in the general population (1) to assess the overlapping of individuals within the different subgroups in those two classifications, (2) to explore if the associations between LBP and some selected bio-psychosocial factors are similar, regardless which of the two classifications is used.

Method

During 1 year, 49- or 50-year-old people from the Danish general population were sent fortnightly automated text messages (SMS-Track) asking them if they had any LBP in the past fortnight. Responses for the whole year were then classified into two different ways: (1) In relation to the number of days with LBP in the preceding year (0, 1–30, and >30), (2) In relation to the frequency and duration of episodes of LBP (more or less never pain, episodic, and more or less constant pain). Some bio-psychosocial factors, collected with a questionnaire at baseline 9 years earlier, were entered into regression models to investigate their associations with the subgroups of the two classifications of LBP and the results compared.

Results

The percentage of agreement between categories of the two classification systems was above 68 % (Kappa 0.7). Despite the large overlap of persons in the two classification groups, the patterns of associations with the two types of LBP definitions were different in the two classification groups. However, none of the estimates were significantly different when the variables were compared across the two classifications.

Conclusion

Different classification systems of LBP are capable of bringing forth different findings. This may help explain the lack of consistency between studies on risk factors of LBP.

     

Asynchronous globin chain synthesis in rabbit reticulocyte lystates induced by hemin-controlled repressor

To define further the role of hemin-controlled repressor (HCR) in globin synthesis, we studied its effect on the synthesis of individual globin chains in a rabbit reticulocyte lysate cell-free system. In the presence of HCR there was a marked globin chain imbalance, resulting in a lowered alpha/beta ratio. These findings in vitro may have relevance to certain clinical heme deficiency states in which a similar globin chain imbalance has been observed.