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John Gibson

Publications and source records attributed to John Gibson.

At least 19 recordsLinked to original sources
PubMed2006

Transformation and progression of Waldenström's macroglobulinemia following cladribine therapy in two cases: natural evolution or iatrogenic causation?

We report two cases of Waldenström's macroglobulinemia with an unusual aggressive transformation following treatment with cladribine (2-chlorodeoxyadenosine, 2-CdA), a purine analogue. The first patient developed transformation to a diffuse large-cell non-Hodgkin lymphoma, while the second developed extensive extramedullary involvement. Both patients displayed rapid progression following transformation and were refractory to chemotherapy. Both patients were pretreated with multiple courses of prednisone and chlorambucil, and transformation occurred shortly after therapy with cladribine. We propose that immune suppression from alkylating agents and purine analogues may have contributed to the unusual progression, resulting in a dismal outcome.

Aged↗
PubMed2006

Autologous or allogeneic stem cell transplantation in patients with Waldenstrom's macroglobulinemia.

The role of hematopoietic stem cell transplantation (SCT) in Waldenstrom's macroglobulinemia (WM) has not been extensively studied. To determine the potential for long-term disease control using SCT in WM, we performed a retrospective review of 36 patients with WM who received autologous (n = 10) or allogeneic (n = 26) SCT and were reported to the Center for International Blood and Marrow Transplant Research between 1986 and 2002. The following outcomes were described: nonrelapse mortality (NRM), relapse, progression-free survival (PFS), and overall survival (OS). Median age at the time of SCT was 51 years (range, 30-76 years), and median time from initial treatment to SCT was 29 months (range, 2-198 months). A total of 78% of the patients had 2 or more previous chemotherapy regimens, and 52% had disease resistant to salvage chemotherapy. In the allogeneic SCT group, 58% of the patients received myeloablative conditioning regimens containing total body irradiation (TBI), and of the allograft recipients, 19% received nonmyeloablative/reduced-intensity conditioning. After a median follow-up of 65 months, 15 of the 36 patients (42%) are alive. Primary disease accounted for 29% of the deaths in the allogeneic SCT group and 25% of the deaths in the autologous SCT group. The relapse rate at 3 years was 29% (95% confidence interval [CI], 14%-48%) in the allogeneic group and 24% (95% CI, 4%-54%) in the autologous group. PFS at 3 years was 31% (95% CI, 14%-50%) in the allogeneic group and 65% (95% CI, 32%-91%) in the autologous group; OS was 46% (95% CI, 27%-65%) in the allogeneic group and 70% (95% CI, 40%-93%) in the autologous group. NRM at 3 years was 40% (95% CI, 23%-59%) in the allogeneic group and 11% (95% CI, 0-36%) in the autologous group. Autologous SCT is a safe and feasible treatment option for patients with WM, especially for those who present with adverse prognostic factors. Allogeneic SCT carries a much higher (40%) risk of NRM and should not be considered outside the context of a clinical trial.

Adult↗
PubMed2006

Computer literacy, skills and knowledge among dentists and dental care professionals (DCPs) within primary care in Scotland.

OBJECTIVE: To gain a better understanding of the level of literacy in information technology (IT) across the dental team working within primary care in Scotland, thus allowing appropriate planning of education and training for effective use of IT. DESIGN: A postal questionnaire survey of all dentists and dental care professionals (DCPs) within primary care in Scotland; online reply was also an option. SETTING: General dental practice and the salaried dental service, May 2004. SUBJECTS AND METHODS: 2679 dentists and 2861 DCPs were surveyed. RESULTS: Forty-three percent of respondents considered their IT skills to be 'moderate', with a further one-third reporting 'nil' or 'low' skill level. Only a quarter of respondents had accessed a learning programme by computer. The majority of IT competence was self-acquired. CONCLUSIONS: 'Upskilling' the dental team in IT may be required in order to take advantage of e-learning opportunities available now and in the future.

Adult↗
PubMed2006

The use of thalidomide in myeloma therapy as an effective anticancer drug.

Thalidomide and its immunomodulatory derivatives have provided the most significant advance in the therapy of myeloma since the introduction of high dose chemotherapy followed by stem cell transplantation nearly 20 years ago. The mechanism of action of thalidomide is complex and involves many aspects of malignant plasma cell growth and bone marrow stromal cell microenvironment interaction. Thalidomide was first used because of its anti-angiogenic properties, however it is the immunomodulatory actions that involve increasing host tumour-specific immunosurveillance by both T cell and natural killer cells which may be the most important mode of action.

Animals↗
PubMed2005

Training in oral disease, diagnosis and treatment for medical students and doctors in the United Kingdom.

To find out if the training of medical undergraduates and qualified doctors was adequate to diagnose, investigate, manage, and refer common oral disorders appropriately, we sent anonymous questionnaires to undergraduate and postgraduate medical and dental deans, accident and emergency (A&E) doctors, and dentists. We wanted to know if they were capable of diagnosing and treating 10 common oral disorders, and if their training was adequate to enable them to do so. Ten clinical photographs with short clinical histories were sent to 48 A&E physicians together with a structured questionnaire. Twenty-one of the 29 medical schools in the UK responded to a questionnaire about the teaching given in the current curriculum about oral anatomy and pathology, and the prevention of oral disease. A questionnaire sent to the deans of the 16 British dental schools asked how many academic staff were involved in undergraduate teaching, and how many in postgraduate courses. A third questionnaire was sent to the 24 postgraduate medical deans to find out how many postgraduate courses there were for qualified medical staff. Of the 48 medical staff, 134 (28%) diagnosed cases correctly, compared with 194 (88.7%) of the 22 dentists, indicating serious deficiencies in diagnostic awareness. Only 11 of the 21 medical schools who responded currently incorporate teaching of oral pathology in their curricula. We conclude that doctors and medical students are inadequately educated about oral diseases with obvious consequences.

Clinical Competence↗
PubMed2005

Botulinum toxin type A (BOTOX) for the prophylactic treatment of chronic daily headache: a randomized, double-blind, placebo-controlled trial.

OBJECTIVE: The objective of this study was to evaluate the safety and efficacy of botulinum toxin type A (BoNT-A; BOTOX, Allergan, Inc.) for the prophylactic treatment of chronic daily headache (CDH). BACKGROUND: Several open-label and small controlled trials suggest that BoNT-A may be effective in the prophylactic treatment of headache. DESIGN AND METHODS: This was an 11-month, randomized double-blind, placebo-controlled study of BoNT-A for the treatment of patients aged 18 to 65 years old with 16 or more headache days per 30 days conducted at 13 North American study centers. Following a 30-day screening period and a 30-day, single-blind, placebo-response period to identify placebo responders, eligible patients from both the placebo responder and placebo nonresponder groups were injected with BoNT-A or placebo every 90 days and assessed every 30 days for 9 months, a period encompassing three treatment cycles. The primary efficacy measure was the change from baseline in the frequency of headache-free days in a 30-day period for the placebo nonresponder group at day 180, the chosen efficacy time point. The secondary efficacy measure was the proportion of patients with a decrease from baseline of 50% or more in the frequency of headache days per 30-day period for the placebo nonresponder group at day 180. The change from baseline in the frequency of headaches (per 30-day period), the proportion of patients with a decrease from baseline of 50% or greater in the frequency of headaches per 30-day period, acute medication use, and adverse events were also assessed. RESULTS: Of 571 patients assessed over the baseline period, 355 (mean age, 43.5 years; 300/355 [84.5%] female) were enrolled and randomized. At the end of the placebo run-in period, 279 patients (79%) were classified as placebo nonresponders and 76 patients (21%) as placebo responders. Subsequently, patients were randomized within each group to receive either BoNT-A or placebo. In the placebo nonresponder stratum, the mean number of headache-free days at baseline was 5.8 (+/-4.7) for BoNT-A- versus 5.5 (+/-4.7) for placebo-treated patients. At day 180, placebo nonresponders treated with BoNT-A had an improved mean change from baseline of 6.7 headache-free days per 30-day period compared to a mean change from baseline of 5.2 headache-free days for placebo-treated patients. The between-group difference of 1.5 headache-free days favored BoNT-A treatment, although the difference between the groups was not statistically significant. However, a statistically significant difference was observed at day 180 endpoint for the secondary efficacy measure. A significantly higher percentage of BoNT-A patients had a decrease from baseline of 50% or greater in the frequency of headache days per 30-day period at day 180 (32.7% vs. 15.0%, P=.027). Also, the mean change from baseline in the frequency of headaches per 30-day period at day 180 was -6.1 for BoNT-A patients vs. -3.1 for the placebo patients (P=.013). Only 4 of 173 BoNT-A patients (2.3%) discontinued the study due to adverse events. The majority of treatment-related adverse events were transient and mild to moderate in severity. CONCLUSIONS: BoNT-A treatment resulted in patients having, on average, approximately seven more (1 week) headache-free days compared to baseline. Although at the primary time point (day 180) the BoNT-A treatment resulted in a 1.5 between-group difference compared to placebo, this difference was not statistically significant. The treatment met secondary efficacy outcome measures, including the percentage of patients experiencing a 50% or more decrease in the frequency of headache days, in addition to statistically significant reductions in headache frequency. BoNT-A was also well tolerated in patients with CDH.

Adolescent↗
PubMed2004

Autologous transplantation for diffuse aggressive non-Hodgkin lymphoma in first relapse or second remission.

We evaluated the results of high-dose chemotherapy and autologous hematopoietic stem cell transplantation in patients with diffuse aggressive non-Hodgkin lymphoma (NHL) in first relapse (Rel 1) or second complete remission (CR 2). Data were evaluated from the Autologous Blood and Marrow Transplant Registry on 429 patients with diffuse aggressive NHL who underwent transplantation in Rel 1 or CR 2. Transplantations were performed between 1989 and 1996 and were reported to the Autologous Blood and Marrow Transplant Registry by 93 centers in North and South America. The probability of 3-year survival was 44% (95% confidence interval [CI], 33%-55%). The probability at 3 years of progression-free survival was 31% (95% CI, 27%-36%). Patients who underwent transplantation in CR 2 had a 3-year probability of progression-free survival of 38% (95% CI, 30%-46%) compared with 28% (95% CI, 22%-33%) for those who were not in remission at the time of transplantation (P <.001). In multivariate analysis, chemotherapy resistance, increased lactic dehydrogenase at diagnosis, an interval of <12 months from diagnosis to relapse, age >or=40 years, and use of myeloid growth factors to accelerate posttransplantation bone marrow recovery were adverse predictors of survival. High-dose chemotherapy and autologous hematopoietic stem cell transplantation for patients with diffuse aggressive NHL in CR 2 or Rel 1 resulted in better outcome for patients with chemotherapy-sensitive disease, longer relapse-free intervals, and age <40 years. Exposure to myeloid growth factors to accelerate recovery for recipients of bone marrow grafts may increase the risk of disease progression or death.

Adolescent↗
PubMed2004

B7+ T cells in myeloma: an acquired marker of prior chronic antigen presentation.

Murine T cells do not endogenously upregulate CD80 expression but rather acquire CD80 from antigen presenting cells (APC) during CD28 ligation. Murine CD80+ memory T cells undergo apoptosis in the presence of high levels of antigen while naive CD80+ T cells are capable of acting as APC and T cell:T cell ligation induces anergy and unresponsiveness to antigen rechallenge. Reversing T cell unresponsiveness may be a key factor in the development of immunotherapy strategies for patients with myeloma. We have determined that B7+ T cells (CD80+ or CD86+) are common in patients with myeloma (n = 45), can be either CD4 or CD8, tend to be associated with stable disease and are polyclonal memory T cells (CD45RO). CD80 mRNA expression was present in CD80+ monocytes but not in CD3+ cells with a similar level of CD80 antigen expression. CD80 and CD86 antigen expression was upregulated on B cells but not T cells during incubation with trimeric human CD40 ligand (huCD40LT) + IL-2. Although there was a gradual loss of expression during in vitro culture, CD80+ T cells could be purified for further study. We conclude that B7 expression is common on T cells of patients with myeloma but that this is acquired rather than endogenously produced. B7+ CD45RO+ T cells constitute a population of memory T cells chronically exposed to antigen and warrant further study.

Animals↗
PubMed2004

Either interleukin-12 or interferon-gamma can correct the dendritic cell defect induced by transforming growth factor beta in patients with myeloma.

The poor response to immunotherapy in patients with multiple myeloma (MM) indicates that a better understanding of any defects in the immune response in these patients is required before effective therapeutic strategies can be developed. Recently we reported that high potency (CMRF44(+)) dendritic cells (DC) in the peripheral blood of patients with MM failed to significantly up-regulate the expression of the B7 co-stimulatory molecules, CD80 and CD86, in response to an appropriate signal from soluble trimeric human CD40 ligand. This defect was caused by transforming growth factor beta(1) (TGFbeta(1)) and interleukin (IL)-10, produced by malignant plasma cells, and the defect was neutralized in vitro with anti-TGFbeta(1). As this defect could impact on immunotherapeutic strategies and may be a major cause of the failure of recent trials, it was important to identify a more clinically useful agent that could correct the defect in vivo. In this study of 59 MM patients, the relative and absolute numbers of blood DC were only significantly decreased in patients with stage III disease and CD80 up-regulation was reduced in both stage I and stage III. It was demonstrated that both IL-12 and interferon-gamma neutralized the failure to stimulate CD80 up-regulation by huCD40LT in vitro. IL-12 did not cause a change in the distribution of DC subsets that were predominantly myeloid (CD11c+ and CDw123-) suggesting that there would be a predominantly T-helper cell type response. The addition of IL-12 or interferon-gamma to future immunotherapy trials involving these patients should be considered.

B7-1 Antigen↗
PubMed2003

Double-blind, placebo-controlled study of the safety and efficacy of botulinum toxin type A for patients with glabellar lines.

The objective of this study was to evaluate the efficacy and safety of botulinum toxin type A for the treatment of glabellar lines. Patients with moderate or severe glabellar lines at maximal frown received intramuscular injections of placebo or 20 U of botulinum toxin type A (Botox; Allergan, Inc., Irvine, Calif.) distributed among five injection sites (one in the procerus muscle and two in each corrugator supercilii). Follow-up assessments were performed at 7, 30, 60, 90, and 120 days after injections. Efficacy measures were the physician's rating of glabellar line severity at maximal frown and at rest (none, mild, moderate, or severe) and the patient's global assessment of changes in glabellar lines, from +4 (100 percent better) to -4 (100 percent worse). A total of 273 patients were enrolled (botulinum toxin, 202 patients; placebo, 71 patients). All except five patients (botulinum toxin, two patients; placebo, three patients) completed the study. For the physician's rating at maximal frown, the responder rate (percentage of patients with severity ratings of none or mild in follow-up evaluations) for the botulinum toxin group peaked at 77 percent at day 30 and was significantly greater than that for the placebo group at every follow-up visit (p < 0.001). For the patient's assessment, the responder rate (percentage of patients with scores of +2 or more) for the botulinum toxin group peaked at 89 percent at day 30 and was significantly greater than that for the placebo group at every follow-up visit (p < 0.001). Rates of adverse events were similar for the two groups. The only adverse event with an incidence of >/=5 percent was headache (botulinum toxin, 11 percent; placebo, 20 percent). The incidence of blepharoptosis was 1 percent for the botulinum toxin group. Botulinum toxin type A was remarkably safe and effective in reducing glabellar lines.

Botulinum Toxins, Type A↗
PubMed2003

Comparison of autologous and allogeneic hematopoietic stem cell transplantation for follicular lymphoma.

In this article, we report on 904 patients undergoing transplantation for follicular lymphoma. A total of 176 (19%) received allogeneic, 131 (14%) received purged autologous, and 597 (67%) received unpurged autologous transplants. Five-year treatment-related mortality (TRM) rates were 30%, 14%, and 8% and 5-year recurrence rates were 21%, 43%, and 58% after allotransplantation, purged autotransplantation, and unpurged autotransplantation, respectively. In multivariate analyses, allotransplantation had higher TRM and lower disease recurrence. Purged autotransplantation had a 26% lower recurrence risk than unpurged autotransplantation. Five-year probabilities of survival were 51%, 62%, and 55% after allogeneic, purged autotransplantation, and unpurged autotransplantation, respectively. Advanced age, prolonged interval from diagnosis to transplantation, high lactate dehydrogenase (LDH), refractory disease, bone marrow involvement, low performance scores, and transplantation between 1990 and 1993 were associated with adverse outcomes. Total body irradiation was associated with higher TRM but lower recurrence. There was no association between acute or chronic graft-versus-host disease and recurrence after allotransplantation. We conclude that both allogeneic and autologous transplantation can induce durable remissions. There may be a benefit to graft purging in autologous transplantation. The decreased recurrence after allotransplantation is offset by increased TRM. We did not detect a correlation between graft-versus-host disease (GVHD) and recurrence. Finally, outcomes of transplantation for follicular lymphoma show improvement over the past decade.

Adult↗
PubMed2003

Susceptibility of heat shock protein 70.1-deficient C57BL/6 J, wild-type C57BL/6 J and A/J mice to Trypanosoma congolense infection.

The heat shock protein (HSP) 70.1 gene lies on mouse chromosome 17 among the candidates for Tir1, the major quantitative trait locus associated with response to Trypanosoma congolense infection. To evaluate whether the HSP70.1 gene is involved in the response, we compared the susceptibility of HSP70.1-deficient C57BL/6 J, resistant wild-type C57BL/6 J and susceptible A/J mice. No differences were observed between HSP70.1-deficient and wild-type C57BL/6 J mice in survival time, levels of parasitemia and anemia, suggesting that there is no involvement of the HSP70.1 gene in control of T. congolense infection. The course of infection was markedly different between A/J and C57BL/6 J mice. A/J mice showed a bi-phasic survival pattern, which seemed to be associated with two waves of high parasitemia, but developed only moderate anemia. C57BL/6 J mice controlled parasitemia well but developed severe anemia in the late stage of infection.

Animals↗
PubMed2003

Clonal cytotoxic T cells in myeloma.

Multiple myeloma (MM) is a malignant disease characterized by accumulation of morphologically recognizable plasma cells producing immunoglobulin (Ig) in the bone marrow. The occurrence of clonal T cells in MM, as defined by the presence of rearrangements in the T-cell receptor (TCR)-beta chains detected on Southern blotting, is associated with an improved prognosis. This review aims to describe the various ways in which we have demonstrated the presence of such T cell clones, and to describe the phenotype of these cells. Finally, the specificities of these clinically important CD8+ T cell populations will be discussed in the context of immunotherapy.

Bone Marrow↗
PubMed2003

Prediction of high affinity class I-restricted multiple myeloma idiotype peptide epitopes.

Idiotypic determinants are potential patient-specific tumor antigens in multiple myeloma (MM). In this study, we have determined the DNA sequence of the variable region of the tumor immunoglobulin (Ig) in 6 patients with MM. We then selected high affinity class I-restricted T-cell peptide epitopes in tumor Ig using two different internet-based epitope prediction programs. High affinity binding peptides were identified by at least one program in 4 out of 6 patients. Of these 35 peptides, only 3 scored high by both analyses. Given that all 6 patients had expanded T-cell clones with a cytotoxic (CD57+CD8+CD28-perforin+) phenotype, known to be associated with a longer survival and postulated to recognise tumor epitopes, this analysis indicates that such clones are unlikely to be exclusively directed towards tumor immuoglobulin, and suggests the need to expand the scope of the search for tumor epitopes with the ability to stimulate cytotoxic T cells in vivo.

Adult↗
PubMed2002

A comparison of allogeneic and autologous bone marrow transplantation for lymphoblastic lymphoma.

Lymphoblastic lymphoma (LBL) is a rare, clinically aggressive neoplasm of the young that frequently involves the bone marrow (BM) and/or central nervous system. Because LBL is similar to acute lymphoblastic leukemia, some centers prefer allogeneic hematopoietic stem cell (SC) transplantation to autologous SC transplantation. We retrospectively analyzed outcomes for patients who underwent autologous (auto, n = 128) or HLA-identical sibling (allo, n = 76) SC transplantations from 1989 to 1998 and were reported to International Bone Marrow Transplant Registry (IBMTR) or Autologous Blood and Marrow Transplant Registry (ABMTR). Allo stem cell transplant (SCT) recipients had higher treatment-related mortality (TRM) at 6 months (18% versus 3%, P =.002), and this disadvantage persisted at 1 and 5 years. Early relapse rates after alloSC transplantation and autoSC transplantation were similar, but significantly lower relapse rates were observed in alloSCT recipients at 1 and 5 years (32% versus 46%, P =.05; and 34% versus 56%, P =.004, respectively). No differences were noted in lymphoma-free survival rates between alloSC transplantations and autoSC transplantations (5-year rates 36% versus 39%, P =.82). AutoSCT recipients had higher overall survival at 6 months (75% versus 59%, P =.01), but survival did not significantly differ between the 2 groups at 1 and 5 years (60% versus 49%, P =.09; 44% versus 39%, P =.47, respectively). Multivariate analyses to account for confounding factors confirmed these results. Independent of SCT type, BM involvement at the time of transplantation and disease status more advanced than first complete remission were associated with inferior outcomes. In summary, alloSC transplantation for LBL is associated with fewer relapses than with autoSC transplantation, but higher TRM offsets any potential survival benefit.

Adolescent↗
PubMed2002

5.1 The demography of oral diseases, future challenges and the implications for dental education.

This Section considered the immense challenges presented by the changing demography of populations (in particular, cross-boundary flow), changing oral and dental disease trends. It also considered the difficulties of gathering data on such information. It then considered how these challenges may affect the education of the dental team in the future. The Section considered the concept of the 'global village' as a representation of the changing world demography. We were at pains to recognize that our role was in considering both emerging and established market economies. In fact, a major part of the Section's activities concentrated on the development of the professional ethic of social responsibility - represented at the local, regional, national and international levels. We considered a finite group of oral and dental diseases, namely dental caries, periodontal diseases, oral cancer and cranio-facial disorders. In addition, we chose to comment on systemic diseases influenced by oral diseases, oral diseases influenced by systemic diseases and iatrogenic diseases (including prion disorders and cross-infection control issues). The Section recognized the profound difference between needs and demands in the provision of oral and dental health care. We considered the concept of best practices within our working remit and named these as: * the gathering of valid data on health trends; * uniformity in the measurement of disease and diagnostic parameters; * the identification of a core curriculum which best addresses an increased awareness of changing demography; and * a multidisciplinary approach to education and research in the context of global collaboration. The Section recognized the enormous potential for global networking with the explosion of information and communication technology. We investigated the requirements in converging towards higher global standards, while accepting and appreciating important regional and continental differences. To this end, the Section has put forward a number of important recommendations and realistic goals.

Computer Communication Networks↗
PubMed2002

The biology and cytogenetics of multiple myeloma.

Despite the advances in our knowledge of myeloma cell biology, our understanding of myeloma pathogenesis is still incomplete. In this review, we present a summary of the cellular and molecular aspects of B-cell development and immunoglobulin (lg) gene rearrangement which have been important in defining the characteristics of the myeloma plasma cell (MPC). The PMC has undergone variable gene recombination, somatic hypermutation and isotype switching, and is therefore at a postgerminal center stage of development. The finding of preswitch clonal cells and isotype variants have raised interesting questions about the cell of origin of myeloma, for which no conclusive data is as yet available. However much information has been obtained about the chromosomal and genetic aberrations in myeloma, including monosomy 13, Ig heavy chain (IgH) switch region translocations, numerical abnormalities and a multitude of heterogeneous changes. A variety of techniques have been developed to overcome the insensitivity of conventional karyotyping, utilizing molecular cytogenetic strategies ranging from the delineation of precise loci by fluorescent in situ hybridization, a more "global" assessment of the genome by multicolor spectral karyotyping, to the quantitation of chromosomal material of specific origin by comparative genomic hybridization. Whether the abnormalities detected represent oncogenic insults, are involved in disease progression or are simply "by-products" of genetic instability is still unclear. For IgH translocations, the role of candidate genes such as Cyclin D1 and FGFR3 has been studied extensively by quantitating their expression and assessment of their oncogenicity (e.g. for FGFR3) in animal models. The significance of other aberrations such as c-myc, ras and p53 has also been investigated. With the advent of oligonucleotide microarrays, the expression of thousands of genes can be efficiently examined. So far, this approach seems promising in defining subgroups of different disease behavior, and may highlight specific genes and molecular mechanisms which are important in myeloma pathogenesis.

Animals↗