Heterogeneity of B cell involvement in acute nonlymphocytic leukemia

In order to study the pattern of B cell involvement in acute nonlymphocytic leukemia (ANLL), multiple B lymphoid cell lines were established by Epstein-Barr virus transformation of peripheral blood mononuclear cells from two patients with the disease who were heterozygous for the X chromosome-linked glucose-6-phosphate dehydrogenase (G6PD). In one patient, the progenitor cells involved by the leukemia exhibited multipotent differentiative expression, whereas in the other patient the cells showed differentiative expression restricted to the granulocytic pathway. In the patient whose abnormal clone showed multipotent expression, the ratio of B-A G6PD in B lymphoid cell lines was skewed in the direction of type B (the enzyme characteristic of the leukemia clone) and significantly different from the 1:1 ratio expected. It is, therefore, likely that the neoplastic event occurred in a stem cell common to the lymphoid series as well as to the myeloid series. In contrast, evidence for B cell involvement was not detected in the patient whose ANLL progenitor cells exhibited restricted differentiative expression. These findings underscore the heterogeneity of ANLL. Clinically and morphologically similar malignancies in these two patients originated in progenitors with different patterns of stem cell differentiative expression. This difference may reflect differences in cause and pathogenesis.     

A "public" T-helper epitope of the E7 transforming protein of human papillomavirus 16 provides cognate help for several E7 B-cell epitopes from cervical cancer-associated human papillomavirus genotypes.

We have identified a major T-cell epitope, amino acids 48-54 (DRAHYNI, in one-letter code) in the E7 open reading frame protein of human papillomavirus (HPV) type 16. Lymph node cells from mice immunized with synthetic peptides containing DRAHYNI proliferated and produced interleukin when challenged in vitro with peptide or whole HPV-16 E7 fusion protein. The T epitope was recognized in association with all five major histocompatibility complex class II I-A and I-E alleles tested. Synthetic peptides consisting of DRAHYNI linked to major B-cell epitopes on the E7 molecule formed immunogens capable of eliciting strong antibody responses to HPV-16 E7. The T epitope could provide help for the production of antibody to several B epitopes simultaneously, including a B epitope of HPV-18 E7 protein. Mice immunized with a peptide containing DRAHYNI and B epitope and, at a later date, infected with recombinant vaccinia E7 virus, displayed secondary antibody responses to E7. Because E7 has a role in cell transformation and is the most abundant viral protein in HPV-associated neoplastic cervical epithelial cells, the data have implications for vaccine strategies.     

Retrospective Analysis of Ponticulus Posticus in Indian Orthodontic Patients-A Lateral Cephalometric Study

Background

The lateral cephalogram is the most common diagnostic radiograph used in clinical orthodontics. Significant cervical spine pathology can be detected on the routine lateral cephalogram. The aim of this study is to sensitize clinicians for examining the cervical area of lateral cephalogram carefully and thus record anatomical variations.

Materials and Methods

The presence and types of ponticuli posticus were investigated on 650 lateral cephalograms which were randomly selected from archived records at AECS Maaruti College of Dental Sciences & Research Centre, Bangalore

Results

The prevalence rate of Ponticulus Posticus in our study was found to be 11.1%. Though there was slight female predominance of 11.7% as compared to 10.4% in males, difference was not statistically significant.

Conclusion

Ponticulus posticus is a common anomaly in the Indian population. If any such anomaly is detected or suspected, it must be documented in the patient''s health record and specialist consultation must be sought. The lateral cephalogram must thus be considered as one of the baseline screening tool for detecting anomalies and pathology in the cervical spine region.     

温热治疗肿瘤的基础研究进展

在肿瘤治疗学中,温热治疗是指运用不同方法对恶性肿瘤进行热治疗,他常与放疗、化疗联用,肿瘤的温度常在40-43℃．现综述温热治疗的细胞死亡、体内温热治疗的特征以及温热治疗的效应器等方面的研究进展．     

Multiple sclerosis: serial study of gadolinium-enhanced MR imaging

Thirteen patients with definite multiple sclerosis (MS), studied 16-24 months previously with magnetic resonance (MR) imaging with and without enhancement by intravenously administered gadolinium diethylenetriaminepentaacetic acid (DTPA) dimeglumine, were reexamined with a similar protocol. Assessment of enhancement and clinical activity in both studies revealed that enhancement was observed in 13 of 14 cases in which clinical activity had changed within 4 weeks of the study and thus appeared more sensitive than clinical examination in determining active disease. The 3-minute postinjection, short repetition time image (TR) was the most efficient for depicting enhancement. Enhancing lesions (active plaques) arose from previously hyper- or isointense regions on long TR images. Previously active lesions reverted to areas of iso- or hyperintensity on long TR images. Serial comparison of long TR images in this population reveals a decrease in high-intensity lesions on long TR images in some cases and an increase in others. The findings of high-intensity regions on long TR images and previously enhancing lesions both becoming isointense suggests that transient inflammatory changes with concomitant edema without demyelination and/or with significant remyelination may occur in some MS lesions. MS lesions are dynamic; both active and inactive lesions may show dramatic change on longitudinal MR imaging studies.     

Peripheral tolerance to human papillomavirus E7 oncoprotein occurs by cross-tolerization, is largely Th-2-independent, and is broken by dendritic cell immunization

The E7 oncoprotein of human papillomavirus 16 functions as a tumor-specific antigen in transformed epithelial cells of the uterine cervix to which immunotherapeutic strategies aimed at CTL induction may be directed. We previously have shown in mice transgenic for the E7 gene driven off an epithelial specific (keratin-14) promoter, that expression of E7 protein in peripheral epithelium is sufficient to tolerize E7-directed CTL precursors (pCTL; Doan et al, J. Virol., 73: 6166-1670, 1999). Here we show that E7 is presented to T cells for tolerization by cells of bone marrow origin ("cross-tolerization"). We demonstrate that tolerization of E7-directed pCTLs occurs within 2 weeks of exposure to E7 in epithelium. It is maintained in the near absence of CD4+ cells and in the absence of the thymus, and is independent of a coexisting E7-directed Th2-type antibody response. Tolerance was broken by immunization with E7 CTL epitope-pulsed dendritic cells. These findings have implications for immunotherapy of patients with human papillomavirus 16-associated cervical carcinoma, whose immune systems may have experienced long-term exposure to E7-expressing epithelial cells.     

Blood donation-related neurologic needle injury: evaluation of 2 years' worth of data from a large blood center

BACKGROUND: There is little information in the medical literature on t he clinical spectrum of blood donation-related neurologic needle injury and on its frequency in a blood donor population. STUDY DESIGN AND METHODS: Sixty-six cases of blood donation-related neurologic needle injury were identified from nursing reports made during a 2-year collection period involving 419,000 whole blood donations. Telephone follow-up was completed on 56 of the 66 cases to better define clinical symptoms, the donor's desire for physician consultation, recovery times, and residual effects. RESULTS: Symptoms in 66 donors included numbness or tingling (n = 54), excessive or radiating pain (n = 43), and loss of arm or hand strength (n = 8). Of the 56 donors with complete follow-up, 17 (30%) consulted a physician one or more times. Recovery times in these 56 donors were <3 days (n = 22), 4 to 29 days (n = 17), 1 to 3 months (n = 13) 3 to 6 months (n = 2), and >6 months (n = 2). Fifty-two of 56 donors achieved a full recovery, and 4 other donors had only a mild, localized, residual numbness. The incidence of blood donation-related neurologic needle injury was 1 of every 6300 donations. CONCLUSION: While donor recovery may in some cases require a great deal of time and/or physician consultation(s), total recovery appears to be the rule. The incidence of blood donation-related neurologic needle injury is relatively low.     

Caring for carers of people with stroke: developing a complex intervention following the Medical Research Council framework

OBJECTIVE: To develop an intervention, using the first three phases of the Medical Research Council (MRC) framework for complex interventions, to facilitate coping skills in new carers of stroke patients. METHODS: In the preclinical (theoretical) phase, a theoretically based framework for a small group course for carers of people with stroke was developed. The intervention was grounded in a cognitive behavioural model and included carers' needs identified from a literature review. Phase I (modelling phase) comprised a qualitative study involving one-to-one semi-structured interviews with a purposive sample of informal carers of people with stroke. Following this, the intervention was modified. In phase II (exploratory phase), the modified intervention was delivered by a clinical psychologist and stroke nurse practitioner to five carers. Following postcourse interviews the course was further refined and delivered to seven new carers who subsequently completed a satisfaction questionnaire. RESULTS: Carers' needs identified from the literature included information provision; managing emotions; social support; health maintenance; and practical problem solving. Consultation with existing carers confirmed these as important issues with a strong emphasis on finding niches of control in life, becoming an expert carer, and dealing with emotional upheaval. Participants reported feeling more optimistic and empowered subsequent to the course. CONCLUSIONS: The MRC framework provided a useful methodology for the development of a complex intervention. The course aimed to assist carers to regain control over aspects of their lives and manage their emotions. It was feasible to run and acceptable to carers; however a randomized controlled trial (RCT) is required to evaluate its effectiveness.     

Purging of T-lymphocytes with magnetic affinity colloid

There is a well-documented correlation between the number of T-lymphocytes in the bone marrow graft and subsequent development of acute graft-versus-host disease after allogeneic bone marrow transplantation. The incidence of acute graft-versus-host disease may be decreased with elimination of mature T-lymphocytes from the bone marrow graft. We have developed an immunomagnetic separation procedure using an avidin-based magnetic affinity cobalt colloid. Bone marrow cells were incubated with a combination of CD2, CD3, CD4, and CD8 monoclonal antibodies. The cells were washed and then incubated with the biotinylated, affinity-purified IgG fraction of goat anti-mouse immunoglobulins followed by an avidin-based magnetic affinity colloid. The cells were then run through a high-magnetic gradient separation column utilizing an external samarium cobalt magnet. The number of residual T-lymphocytes was assessed by limiting dilution analysis of clonogenic T-lymphocytes. This procedure produces an approximately 1.7-log reduction of antibody-reactive cells with 45% recovery of hematopoietic progenitors (granulocyte-macrophage colony-forming cells, GM-CFC). This causes a reduction of T-lymphocytes in the bone marrow graft to approximately 5 x 10(5) cells/kg body weight.     

Digital beam attenuator technique for compensated chest radiography

The feasibility of producing patient-specific beam attenuators for chest radiography has been investigated using an anthropomorphic phantom and a human volunteer. A low-dose test exposure is digitized, processed, and used to print a small cerium filter, which is placed in the x-ray beam near the collimator. The final radiograph is recorded on film. The technique results in relatively uniform film exposure, so that structures in all regions of the chest are simultaneously displayed with optimal film contrast. The equalized exposure improves image quality in the normally underpenetrated regions and reduces the role of cross-scatter from the lungs. The image is analogous to optical or computer-processed unsharp masking techniques, but the processing is accomplished in the x-ray beam and results in an improved exposure distribution, giving advantages that cannot be achieved with image processing techniques alone.