Defective gap junctional intercellular communication in lung cancer: loss of an important mediator of tissue homeostasis and phenotypic regulation

Gap junctions provide direct pathways for the exchange of molecules and ions between neighboring cells, a process known as gap junctional intercellular communication (GJIC). This GJIC is important for homeostasis and regulation of mitosis, differentiation, and apoptosis. Gap junctions are present in lung airway and alveolar epithelial cells and, in addition to the above roles, might coordinate ciliary beating and surfactant secretion. GJIC is decreased in human and mouse lung carcinoma cells because of reduced expression of the gap junction protein, connexin43 (Cx43), and defects in signal transduction pathways that mediate Cx43 function. This reduced GJIC is important in the behavior of lung carcinoma cells because forced expression of Cx43 in lung carcinoma cells inhibits their growth and tumorigenicity. In this report, we summarize our studies on the role of GJIC in lung neoplasia.

Memory for murder. A psychological perspective on dissociative amnesia in legal contexts

There is currently a complex and inconsistent state in the law relating to dissociation and dissociative amnesia (McSherry, 1998). Although dissociative amnesia in defendants is relevant to both competency to stand trial and criminal responsibility in principle, courts have typically assumed a skeptical stance toward such claims in practice. However, there is considerable evidence from both nonoffender and offender populations to support the validity of dissociative amnesia in defendants. Further, there is information available to aid in the evaluation of amnesia, such as the quality of the report itself and characteristics of the person reporting the amnesia (e.g., psychopathy). When consideration is given to the legal response to reports of dissociative amnesia by complainants, the situation becomes even more complex. While some courts have rejected recovered memory evidence, others have convicted defendants of historical offenses based on such evidence. In some cases, judges have argued that jurors should be left to decide on the validity of recovered memories based on their common sense and experience. The uncritical acceptance of the validity of repressed memories in complainants by many courts stands in stark contrast to the response to claims of amnesia from defendants. It seems apparent that the courts need better guidelines around the issue of dissociative amnesia in both populations. We think that the increasing scientific understanding of memory in the past decade (see Schacter, 1999) can meaningfully contribute to the development of such guidelines. Responsible, nonpartisan expert testimony from mental health professionals would be one step in the direction of rectifying the current state of law in regards to dissociation.

Human immune response to recombinant human proteins

Delivery of pharmacological doses of proteins to people has raised concerns of inducing immune responses, especially when the protein is provided in multiple doses over an extended period of time. Immune responses could impact the therapeutic exposure and efficacy of the protein itself. In addition, there have been fears of anaphylaxis or autoimmunity. This review summarizes the available literature regarding the measurement and evaluation of immune responses observed during clinical assessment of recombinant human proteins. Immune responses have ranged from none at all to inactivation and/or accelerated clearance. Presence of antibodies does not necessarily impact therapeutic viability. While responses are related to frequency and route of delivery, there is no clear relationship that enables one to predict the clinical experience.

Truth, lies, and videotape: an investigation of the ability of federal parole officers to detect deception

The ability of a group of Canadian federal parole officers to detect deception was investigated over the course of 2 days of lie detection training. On the first day of training, 32 officers judged the honesty of 12 (6 true, 6 fabricated) videotaped speakers describing personal experiences, half of which were judged before and half judged after training. On the second day, 5 weeks later, 20 of the original participants judged the honesty of another 12 videotapes (again, 6 pre- and 6 posttraining). To isolate factors relating to detection accuracy, three groups of undergraduate participants made judgments on the same 24 videotapes: (1) a feedback group, which received feedback on accuracy following each judgment, (2) a feedback + cue information group, which was given feedback and information on empirically based cues to deception, and (3) a control group, which did not receive feedback or cue information. Results indicated that at baseline all groups performed at or below chance levels. However, overall, all experimental groups (including the parole officers) became significantly better at detecting deception than the control group. By the final set of judgments, the parole officers were significantly more accurate (M = 76.7%) than their baseline performance (M = 40.4%) as well as significantly more accurate than the control group (M = 62.5%). The results indicate that detecting deceit is difficult, but training and feedback can enhance detection skills.

Biomaterial developments for bone tissue engineering

The development of bone tissue engineering is directly related to changes in materials technology. While the inclusion of materials requirements is standard in the design process of engineered bone substitutes, it is also critical to incorporate clinical requirements in order to engineer a clinically relevant device. This review presents the clinical need for bone tissue-engineered alternatives to the present materials used in bone grafting techniques, a status report on clinically available bone tissue-engineering devices, and recent advances in biomaterials research. The discussion of ongoing research includes the current state of osseoactive factors and the delivery of these factors using bioceramics and absorbable biopolymers. Suggestions are also presented as to the desirable design features that would make an engineered device clinically effective.

Human herpesvirus 8 and oral health care: an update

OBJECTIVE

The purpose of this report was to review the current literature on human herpesvirus 8 (HHV-8) with particular attention to the aspects of interest for dental health care workers.

MATERIAL AND METHODS

The authors searched original research and review articles on specific aspects of HHV-8 infection, including virology, epidemiology, transmission, diagnosis, natural history, therapy, and oral aspects. The relevant material was evaluated and reviewed.

RESULTS

HHV-8 is a recently discovered DNA virus that is present throughout the world but with major geographic variation. In the Western world, the virus, transmitted mainly by means of sexual contact, is strongly associated with Kaposi's sarcoma and body cavity-based lymphoma and more controversially with multiple myeloma and non-neoplastic disorders. There is no specific effective treatment, but human immunodeficiency virus protease inhibitors may play an indirect role in the clearance of HHV-8 DNA from peripheral blood mononuclear cells of patients infected with human immunodeficiency virus. HHV-8 DNA is present in saliva, but as yet, there are no documented instances of nosocomial transmission to health care workers. The prevalence of HHV-8 among dental health care workers is probably similar to that in the general population.

CONCLUSION

HHV-8 does not appear to be ubiquitous in most populations, particularly in western Europe and the United States, where it may be restricted to a population at risk of having Kaposi's sarcoma develop (men infected with human immunodeficiency virus and patients who are iatrogenically immunosuppressed). Most serologic studies suggest a global HHV-8 seroprevalence of 2% to 10% and show that the virus may be under immunologic control in people who are healthy but infected with HHV-8. Also, HHV-8 certainly has the means to overcome cellular control and immune responses and thus predispose to malignancy. To date, there are no data to suggest that health care staff members are at particular risk of HHV-8 acquisition through occupational routes.

Negotiating false memories: interviewer and rememberer characteristics relate to memory distortion

In a recent study, more than half of the participants were led to create a partial or complete false memory for an emotional childhood event (e.g., serious animal attack). Using a subsample from that study, we examined the hypothesis that memory distortion is related to characteristics of interviewers and rememberers. The relations between susceptibility to memory distortion and (a) dissociation (Dissociative Experiences Scale) and (b) personality traits (NEO-Five Factor Inventory) were investigated. Results indicated that participants who exhibited memory distortion scored significantly higher on the dissociative scale than their counterparts who did not exhibit memory distortion. Further, susceptibility to memory distortion was associated with higher extraversion scores in interviewers and lower extraversion scores in participants. This pattern of findings suggests that false memories may derive from a social negotiation between particular interviewers and rememberers.

The recurrence of deformity after surgical centralization for radial clubhand

Fourteen children representing 19 cases of radial clubhand had centralization of the carpus on the distal ulna during an 18-year period. Age at the time of the initial surgery averaged 3.2 years (range, 0.7-8.1 years) and the follow-up periods averaged 6.5 years (range, 1.5-22.2 years). There were 16 type IV radial and 3 type III clubhands. Preoperative, postoperative, and follow-up x-rays were used to determine the initial deformity, amount of surgical correction, and degree of recurrence. The total angulation (the combination of the radial deviation of the hand and the ulna bow) was measured. The average preoperative angulation measured 83 degrees (range, 55 degrees to 110 degrees ). Centralization corrected the angulation an average of 58 degrees (range, 15 degrees to 95 degrees ) to an average immediate postoperative total angulation of 25 degrees (range, 5 degrees to 60 degrees ). At the final follow-up examination there was a loss of 38 degrees (range, 5 degrees to 105 degrees ) and the total angulation increased to an average of 63 degrees (range, 20 degrees to 120 degrees ). The difference between the preoperative, postoperative, and follow-up angles was statistically significant. There was a significant correlation between the preoperative angle and the final angle, the preoperative angle and the amount of correction, the amount of correction obtained at surgery and the recurrence of the deformity, and the age at time of initial surgery and the amount of recurrence.

Cost-effective prescribing of proton pump inhibitor therapy: an audit in general practice

General practitioners must prescribe cost effectively to control drug expenditure and provide optimal treatment for patients requiring long-term management. An audit was implemented in general practices to review the management of dyspepsia, improve care, rationalise therapy and reduce costs. Policy included identifying patients receiving proton pump inhibitor (PPI) therapy and changing to low-dose cost-effective therapy. If PPI therapy was not required, patients were changed to antacids, H2 receptor antagonists or no treatment. This was an audit in general practice, not a clinical trial, therefore findings reflect outcomes in normal clinical practice. This paper describes the implementation and findings of the audit between January 1997 and July 1999 in 91 general practices involving 7121 patients. Extrapolation of the results concluded that savings of up to 50,000 Pounds could be made in a practice of 10,000 patients, allowing reinvestment in health improvement plans and optimal care.

The human transmissible spongiform encephalopathies (TSEs): implications for dental practitioners

Transmissible spongiform encephalopathies (TSEs) are rare, fatal degenerative brain diseases which affect humans and certain animals, and are caused by inheritance or acquisition of prions (PrPs). Inherited TSEs include Fatal Familial Insomnia (FFI), Gerstmann-Straussler-Scheinker syndrome (GSS) and other less well clinically characterised disorders, while the human infective TSEs include sporadic, iatrogenic and variant Creutzfeldt-Jakob disease (vCJD). The causative prions are found especially in neural tissues and spinal fluid, and in the case of vCJD, in lymphoreticular tissue. Available epidemiological evidence suggests that normal social or routine clinical contact with affected patients does not present a risk to health care workers, relatives or the community. Isolation of patients is not considered necessary. Nevertheless as the prions are resistant to conventional chemical, irradiation and heat sterilisation methods, highly specific cross-infection control measures are required for the dental management of patients with, or at notable risk, of TSE. The present article reviews current knowledge of the clinical consequences of prion disease and provides information regarding necessary changes to the cross-infection routine when managing patients infected, or at risk of, prion disease.

HIV topic update: oro-genital transmission of HIV

Several viruses, including the human immunodeficiency virus (HIV), can be found in blood and many body fluids including saliva, and are transmissible sexually across genital and particularly anal mucosae. A persisting concern has been the question of transmission of HIV by oral sexual practices. This review discusses the evidence for oro-genital transmission of HIV, detailing the presence and infectivity of HIV in genital fluids and saliva, the case reports and epidemiology of oro-genital HIV transmission, and the evidence from animal studies. Oral intercourse is not risk-free. The evidence suggests that the risk of HIV transmission from oro-genital sexual practices is substantially lower than that from penile-vaginal or penile-anal intercourse, that exposure to saliva presents a considerably lower risk than exposure to semen, and that oral trauma and ulcerative conditions might increase the risk of HIV transmission.

Orofacial disease: update for the dental clinical team: 11. Cervical lymphadenopathy

By far the most common causes of lumps in the neck are swollen lymph nodes. The most common cause of cervical lymphadenopathy is infection in the area of drainage (virtually anywhere in the head and neck). Most frequent of all is an enlarged jugulodigastric (tonsillar) lymph node, inflamed secondary to a viral upper respiratory tract infection. Enlarged cervical lymph nodes may also be a manifestation of systemic infection (e.g. HIV/AIDS), or related to malignant disease in the drainage area (e.g. carcinoma) or elsewhere (e.g. leukaemia or lymphoma). These and less common causes are discussed in this, the last article in this series.