Follicular dendritic cells: B-cell proliferation and maturation.

Follicular dendritic cells (FDC) play a pivotal role in the initiation and maintenance of the secondary humoral immune response. FDC located in the follicles of secondary lymphoid tissues are part of a special mechanism that handles antigen in a specific antibody-rich environment and are integral members of the antigen transport cell-FDC-iccosome-B-cell axis that leads to the formation of germinal centers, antibody-forming cells, and memory B-cells. This review briefly outlines the basic biology of FDC function and provides a source of pertinent references.

Development of cerebral arterial innervation: synchronous development of neuropeptide Y (NPY)- and vasoactive intestinal polypeptide (VIP)-containing fibers and some observations on growth cones.

The pre- and postnatal development of sympathetic fibers containing neuropeptide Y (NPY) and parasympathetic fibers containing vasoactive intestinal polypeptide (VIP) supplying the cerebral arteries were studied with immunohistochemistry in rats. The innervation patterns and densities of NPY and VIP fibers were similar at all stages of development and similar to that previously reported for norepinephrine (NE). There was a striking reorganization of the innervation pattern of all three fiber systems between the first and second postnatal weeks.

Follicular dendritic cells in the alternative antigen transport pathway: microenvironment, cellular events, age and retrovirus related alterations.

Follicular dendritic cells (FDC) are located in lymphoid follicles of secondary lymphoid tissues and play a pivotal role in the initiation and maintenance of the secondary antibody response. FDC are an integral part of the microenvironment of the follicle and function as members of the 'alternative antigen transport pathway.' This pathway consisting of the antigen transport cell-FDC-ICCOSOME-B cell axis, leads to the formation of germinal centers where antibody-forming cell and memory B cell development are initiated through interaction of FDC-retained antigen, B cells and T helper cells.

Murine follicular dendritic cells and low affinity Fc receptors for IgE (Fc epsilon RII).

The present study was undertaken to determine whether mouse follicular dendritic cells (FDC) bear Fc epsilon RII (CD23) and whether IgE-immune complexes are retained by FDC. Mouse Fc epsilon RII was localized by both L and electron microscopy using the mAb B3B4. In lymph nodes of normal mice, Fc epsilon RII was low but detectable on FDC.

Immunodominant antigens of Actinobacillus actinomycetemcomitans serotype b in early-onset periodontitis patients.

Previous work with Actinobacillus actinomycetemcomitans strain Y4 (serotype b) indicates that the immunodominant antigen in high-responding patients (top 10%, 80% of which were black) is the serotype-specific antigen. In this study we examined the immunodominant antigens of A. actinomycetemcomitans strain Y4 in both black and white patients having a range of antibody titers.

Selective medicals at school entry.

This paper describes a selective procedure for use at school entry based on information from pre-school surveillance, parental questionnaires and class reviews. The pilot study in use over two years shows that the number of new conditions found at age 5 are relatively few in number and the extra time available can be used more appropriately for those with health problems affecting school progress. The job satisfaction for both nurses and doctors is increased and the parents are more fully involved with their child's health and progress.

Association of meningiomas with dural "tails"; surgical significance.

Intracranial meningiomas are characteristically benign tumours with a tendency to recur following surgical resection. Our group is investigating the pathogenesis of meningioma recurrence. In our initial studies we identified two cases of dural "tails" associated with intracranial meningiomas.

Accumulation of plasma cells in inflamed sites: effects of antigen, nonspecific microbial activators, and chronic inflammation.

Plasma cells are common in chronically inflamed sites, including periodontal lesions. The aim of this study was to determine which factors contribute to this local accumulation of plasma cells. Specifically, we sought to evaluate the effects of specific antigen and nonspecific activators from an infectious agent associated with chronic inflammation (Fusobacterium nucleatum, an organism prominent in chronic periodontal lesions) and the effect of the chronic inflammation itself.

Chemotaxis of germinal center B cells in response to C5a.

An infiltrate of B cells and plasma cells is characteristic of certain chronic inflammatory lesions. However, mechanisms involved in the local accumulation of these cells have not been established. Efforts to demonstrate that B cells from normal animals can migrate in response to inflammation-induced chemoattractants have been inconclusive.

Immunodominant antigens of Actinobacillus actinomycetemcomitans serotypes a and c in high-responder patients.

This study was undertaken to examine the characteristics of the immunodominant antigens of Actinobacillus actinomycetemcomitans serotypes a and c. The top responders for A. actinomycetemcomitans serotypes a and c were selected (19 for serotype a and 21 for serotype c) from 150 clinically characterized patients.

Iccosomes and the secondary antibody response.

Iccosomes derived from follicular dendritic cells (FDC) are believed to play an important role in dispersion of antigen necessary for induction of anamnestic responses. Because FDC are aberrant and iccosome release has not been observed in aged mice, we hypothesized that these animals would be impaired in their ability to mount anamnestic responses. To test this, anamnestic responses were compared in aged and control mice.

Germinal center B cells and antibody production in the bone marrow.

In secondary antibody (Ab) responses, Ag processing and presentation occur in secondary lymphoid organs but most serum Ab is produced by cells in the bone marrow. Plasma cells in the bone marrow are derived from B cells activated by Ag in secondary lymphoid organs. We hypothesized that germinal center (GC) B cells, which acquire Ag from follicular dendritic cells in draining lymph nodes during the first few days of the secondary response, migrate to the bone marrow to terminally differentiate and produce specific Ab.

Influence of a carbohydrate-electrolyte beverage on performance and blood homeostasis during recovery from football.

This study compared the efficacy of a 7% glucose polymer beverage containing electrolytes (GP) versus a nonnutrient, nonelectrolyte placebo (P) in maintaining blood homeostasis during recovery from football and determined whether consumption of the GP beverage improved anaerobic performance immediately after football competition when compared with the placebo. Forty-four high school football players participated in a 50-play scrimmage designed to simulate game conditions. At each of six periods before and during the scrimmage, players consumed 170 ml of the GP or P beverage.

The Dolenc technique for cavernous sinus exploration (cadaveric prosection). Technical note.

This report describes a surgical approach to the cavernous sinus. Based on the work of Parkinson, Dolenc, and other pioneering investigators, a comprehensive surgical approach for the treatment of lesions of the cavernous sinus is distilled and presented in 12 simple steps. The approach to surgical exploration of this region is divided into an extradural and intradural phase, each with six steps.

Kinetics of the tingible body macrophage response in mouse germinal center development and its depression with age.

Although tingible body macrophages (TBM) have been recognized in germinal centers for over 100 years, their role in the germinal center response is not clear. In this study, the kinetics of the TBM response was quantitatively assessed and correlated with the kinetics of germinal center development in young mice. The TBM response in old mice (which have an age-related depression of germinal center development; Szakal et al.

Surgical approaches to thoracic disc herniations.

Early diagnosis of thoracic disc herniations has become more common with the advent of spinal magnetic resonance imaging (MRI). This early diagnosis combined with choosing the optimal surgical approach, to ensure adequate decompression without excessive cord and root manipulation, will achieve the optimum results. It is now clear that more lateral and anterior approaches to the thoracic spine are required to achieve this goal.

Management of the acoustic neuroma in an only hearing ear.

Heightened physician awareness of the sociologic and psychologic trauma related to deafness coupled with an increased emphasis on early diagnosis has prompted the employment of sophisticated diagnostic studies in an attempt at identification of an acoustic neuroma as a cause of hearing loss. Because profound bilateral hearing impairment is a catastrophic event, the management and care of an individual with an eighth nerve lesion in an only hearing ear remains a significant challenge for both patient and physician. In this article we will summarize our experience with this unique patient population through case presentations that will include diagnostic testing and intraoperative and perioperative findings.

Concurrent intradural and extradural meningiomas of the cervical spine.

A case of an extradural spinal meningioma presenting with a separate intradural meningioma at the same cord level is reported. Review of the English literature on spinal epidural meningiomas reveals a high incidence of concurrent intradural tumors in patients with epidural meningiomas. This leads to the conclusion that the intradural space should be evaluated carefully when an epidural meningioma is encountered.

Kinetics of germinal center development in lymph nodes of young and aging immune mice.

Recent findings imply that germinal center paucity in old mice, at least in part, results from a defect in the mechanisms responsible for the transport of antigens to lymphoid nodules (follicles) and the consequent impairment of the antigen retaining reticulum (ARR) of follicular dendritic cells (FDCs). The present objective was to observe the kinetics of lymph node germinal center development in old mice having antigen transport and ARR deficits. Germinal center development was monitored in popliteal (PLN) and axillary (AXLN) lymph nodes of 6-8 wk and 23-mo-old horseradish peroxidase (HRP) immune C57BL/6 mice.

Serum antibodies to periodontal bacteria.

The purpose of this study was to determine how serum antibodies reactive with periodontitis-associated bacteria with relates to the diagnosis of periodontitis subjects. Study groups included localized juvenile periodontitis (LJP) subjects, severe periodontitis (SP) subjects, chronic adult periodontitis (AP) subjects, and age matched controls. Twenty-two bacterial strains, representing 18 different species most commonly found in early onset periodontitis were evaluated using serum from LJP, SP, and age matched controls.