Oral function in patients wearing fixed prosthesis on osseointegrated implants in the maxilla: 3-year follow-up study

Seventeen consecutive selected patients rehabilitated by means of a full maxillary bridge on osseointegrated implants ad modem Brånemark were evaluated over a 3-yr period. Besides a subjective evaluation by means of a questionnaire an examination of the occlusal relationship, chewing force, chewing efficiency and interocclusal threshold level was performed before, immediately after, 3–6 months after, and finally 3 yr after bridge installation. All subjects were very pleased with the oral rehabilitation. The chewing force and the chewing efficiency development increased over time, while the threshold level for interocclusal detection remained unchanged. The clinical dysfunction index according to Helkimo indicated that there was no marked change in signs of dysfunction of the patients' masticatory systems during the observation period. From the present longitudinal investigation one can conclude that the replacement of a full maxillary denture with a fixed prosthesis on osseointegrated implants, facing a natural dentition or an osseointegrated implant supported bridge in the opposite jaw, leads to a progressive increase of chewing efficiency and chewing force, and a constant subjective improvement of jaw function, while no masticatory dysfunction seems to occur during the observation period.     

Transgenic mice that express different forms of the influenza virus hemagglutinin as a neo-self-antigen

We have generated transgenic mouse lineages that express the influenza virus hemagglutinin in different physical forms. One kind expresses the full-length hemagglutinin molecule as a cell surface glycoprotein and can be recognized by hemagglutinin-specific B and T cells. The other expresses a truncated polypeptide corresponding to the N-terminal third of the hemagglutinin molecule. This polypeptide encodes known hemagglutinin-specific T-cell determinants; however, it contains no native B-cell epitopes, since these depend on the conformation of the fully folded protein. In each case, the hemagglutinin transgenic mice display ubiquitous expression of transgenic messenger RNA and induce T-cell tolerance to the transgene-encoded T-cell determinant site 1. Thus, the hemagglutinin is a neo-self-antigen in both kinds of hemagglutinin transgenic mice and should provide a useful system for understanding the factors and mechanisms that govern tolerance and autoimmunity to self-antigens.     

Baseline heart rate may predict hypotension after spinal anesthesia in prehydrated obstetrical patients

PURPOSE: Hypotension is the most frequent complication of spinal anesthesia in pregnant patients. This study was designed to identify patients at risk for postspinal hypotension based on preoperative vital signs before and after an orthostatic challenge. METHODS: Forty healthy women scheduled for elective Cesarean section were enrolled in this prospective trial. Blood pressure (BP) and heart rate (HR) were recorded with the patient in the lateral supine position and after standing up. After a bupivacaine spinal anesthetic, BP was obtained every two minutes for 30 min. Ephedrine treatment was administered based on the degree of hypotension observed. Hemodynamic parameters were correlated to ephedrine requirements (Spearman's rank order correlation). RESULTS: There was a significant correlation in baseline maternal HR and ephedrine requirements (P=0.005). The degree of orthostatic changes in mean arterial BP and HR did not correlate with postspinal hypotension. CONCLUSIONS: Baseline HR may be predictive of obstetric spinal hypotension. Higher baseline HR, possibly reflecting a higher sympathetic tone, may be a useful parameter to predict postspinal hypotension.     

Partial purification and characterization of soluble TMV replicase

A soluble TMV replicase (TMV-RNA dependent RNA polymerase) has been partially purified from systemically TMV-infected tobacco leaves. The enzyme was obtained by gel filtration on 8% agarose followed by affinity chromatography on agarose with chemically coupled RNA. The presence of Mg²⁺, all four nucleoside triphosphates, and an RNA were absolutely required for enzyme activity with the purified replicase, which showed some preference for the homologous viral RNA. The product was largely resistant to ribonuclease at high salt concentration. Based on the sedimentation in sucrose gradients, the molecular weight of the replicase was estimated to be 130,000.     

The distribution of terminal sympathetic nerve fibers in bundle branches and false tendons of the bovine heart. An immunohistochemical and catecholamine histofluorescence study

Summary The sympathetic innervation in false tendons as a whole and the distribution of the terminal sympathetic nerve fibers in the conduction tissue in the bundle branches is unclear. Therefore, in the present study, false tendons and bundle branch regions of the bovine heart were examined using tyrosine hydroxylase (TH) immunohistochemistry and the glyoxylic acid induced catecholamine (CA) fluorescence method for demonstration of sympathetic nerve fibers. Acetylcholinesterase (AChE) histochemistry was also applied. Some of the nerve fascicles in the false tendons were found to contain large numers of sympathetic nerve fibers and such nerve fibers formed plexuses in the walls of arteries and arterioles in these structures. In both false tendons and bundle branches sympathetic nerve fibers 1) were non-homogeneously distributed in the conduction tissue, most regularly occurring in the channels of extracellular space that are present within the bundles of Purkinje fibres. and 2) showed the same pattern of distribution in relation to Purkinje fibre bundle surfaces as the AChE-positive nerve branches. The observations show that there is a substantial sympathetic innervation in false tendons. The final distribution of the nerve fibers in these structures and in the bundle branches are discussed in relation to what is known of tissue morphology and the occurrence of sympathetic nerve influences in these regions. In the present study, previous CA-fluorescence observations of a marked sympathetic innervation in bundle branch regions, in terms of the presence of sympathetic nerve fibers in nerve fascicles and vessel walls, were also corroborated by the application of TH-immunohistochemistry.     

Evaluation of Periostat for patient management

The cause of adult periodontitis involves complex bacteria-host interactions, with modifying influences exerted by genetic and environmental factors. Current thinking indicates that successful, long-term management of adult periodontitis requires a treatment approach that takes into account the various etiologic components of the disease. Recently, a formulation containing a subantimicrobial dose of doxycycline (Periostat) was approved for use as an adjunct to scaling and root planing (SRP) in the treatment of adult periodontitis. As an inhibitor of matrix metalloproteinases that have been implicated in the pathologic degradation of connective tissue collagen in periodontal support structures, Periostat in conjunction with SRP was shown to significantly improve clinical attachment and reduce probing depth compared with placebo in conjunction with SRP. This article reviews the clinical trial results leading to US Food and Drug Administration approved of Periostat and discusses the potential use of this host-modulatory agent as a complementary systemic pharmacotherapy in periodontal management programs.     

When acute-stage psychosis and substance use co-occur: differentiating substance-induced and primary psychotic disorders

Substances such as alcohol, cocaine, amphetamine, and cannabis can produce psychotic reactions in individuals who are otherwise free of serious mental illness. However, persons with primary psychotic disorders, such as schizophrenia and bipolar disorder, who use these substances often present for treatment with signs and symptoms similar to those whose psychosis resulted from the use of drugs alone. While it is often difficult to distinguish substance-induced from primary psychoses, especially early in the course of treatment, this differential diagnosis has important implications for treatment planning. To help clinicians distinguish these two types of presentations, the authors first review the types of psychotic symptoms that can co-occur with substance use. They discuss the prevalence and patterns of substance use that have been found in patients with schizophrenia and other primary psychotic disorders and review the negative outcomes associated with substance use in this population. The prevalence of and types of symptoms and problems associated with psychotic symptoms that occur as a result of substance use alone are also reviewed. The authors describe assessment procedures for differentiating substance-induced and primary psychotic disorders. They stress the importance of accurately establishing the temporal relationship between the substance use and the onset and continuation of psychotic symptoms in making a differential diagnosis, as well as the importance of being familiar with the types of psychological symptoms that can occur with specific substances. The authors review the utility and limitations of a number of diagnostic instruments for assessing patients with co-occurring psychosis and substance use problems, including The Addiction Severity Index, The Michigan Alcohol Screening Test, and diagnostic interviews such as the Schedule for Affective Disorders and Schizophrenia and the Structured Clinical Interview for DSM. They then discuss the Psychiatric Research Interview for Substance and Mental Disorders (PRISM), an instrument that has been developed to address the lack of a diagnostic interview that is suitable for assessing the comorbidity of substance use and psychiatric disorders. The article concludes with a discussion of the importance of an appropriate match between diagnosis and treatment and the current state of our knowledge concerning the most appropriate types of treatment interventions for patients with substance-induced psychosis and those with dual diagnoses.