An Industry Perspective on the use of Forced Degradation Studies to Assess Comparability of Biopharmaceuticals

Forced degradation, also known as stress testing, is used throughout pharmaceutical development for many purposes including assessing the comparability of biopharmaceutical products according to ICH Guideline Q5E. These formal comparability studies, the results of which are submitted to health authorities, investigate potential impacts of manufacturing process changes on the quality, safety, and efficacy of the drug. Despite the wide use of forced degradation in comparability assessments, detailed guidance on the design and interpretation of such studies is scarce. The BioPhorum Development Group is an industry-wide consortium enabling networking and sharing of common practices for the development of biopharmaceuticals. The BioPhorum Development Group Forced Degradation Workstream recently conducted several group discussions and a benchmarking survey to understand current industry approaches for the use of forced degradation studies to assess comparability of protein-based biopharmaceuticals. The results provide insight into the design of forced degradation studies, analytical characterization and testing strategies, data evaluation criteria, as well as some considerations and differences for non-platform modalities (e.g., non-traditional mAbs). This article presents survey responses from several global companies of various sizes and provides an industry perspective and experience regarding the practicalities of using forced degradation to assess comparability.

Provider and patient burdens of obtaining oral anticancer medications

Oral anticancer medications (OAMs) are frequently used to treat patients with cancer. Unlike intravenous chemotherapy, OAMs are covered by prescription drug plans. We examined barriers to initiation of OAMs in 116 patients with prostate or kidney cancer (149 unique prescriptions). We found that the median time from initial prescription to prior authorization was 3 days and the median time from initial prescription to patient receipt of drug was 12 days. Seventy-three percent of all prescriptions required 2 or more phone calls by clinic staff and 40% required 5 or more calls. Of 107 prescriptions with data available, 54% utilized financial assistance; these required significantly more phone calls (P = .0001) and led to a longer median time to drug obtainment (P = .003) compared with those that did not require financial assistance. In those prescriptions with both initial and final co-pay information available, the initial out-of-pocket mean and median co-pays were $1226.03 and $329.73, respectively, but these dropped to $124.57 and $25.00 after utilization of co-pay assistance programs, excluding those with a $0 final co-pay. These early observations suggest that a more efficient process for initiation of OAMs is needed.

Nuclear forensic analysis of a non-traditional actinide sample

Nuclear forensic publications, performance tests, and research and development efforts typically target the bulk global inventory of intentionally safeguarded materials, such as plutonium (Pu) and uranium (U). Other materials, such as neptunium (Np), pose a nuclear security risk as well. Trafficking leading to recovery of an interdicted Np sample is a realistic concern especially for materials originating in countries that reprocesses fuel. Using complementary forensic methods, potential signatures for an unknown Np oxide sample were investigated. Measurement results were assessed against published Np processes to present hypotheses as to the original intended use, method of production, and origin for this Np oxide.

Mass transport at rotating disk electrodes: effects of synthetic particles and nerve endings

An unstirred layer (USL) exists at the interface of solids with solutions. Thus, the particles in brain tissue preparations possess a USL as well as at the surface of a rotating disk electrode (RDE) used to measure chemical fluxes. Time constraints for observing biological kinetics based on estimated thicknesses of USLs at the membrane surface in real samples of nerve endings were estimated. Liposomes, silica, and Sephadex were used separately to model the tissue preparation particles. Within a solution stirred by the RDE, both diffusion and hydrodynamic boundary layers are formed. It was observed that the number and size of particles decreased the following: the apparent diffusion coefficient excluding Sephadex, boundary layer thicknesses excluding silica, sensitivity excluding diluted liposomes (in agreement with results from other laboratories), limiting current potentially due to an increase in the path distance, and mixing time. They have no effect on the detection limit (6 ± 2 nM). The RDE kinetically resolves transmembrane transport with a timing of approximately 30 ms.

Cathodic preconcentration of f-elements on a mercury film carbon fiber disk microelectrode

Field detection and quantification of f-elements is an important problem in radioanalytical chemistry requiring small, portable devices. Here, characterization of a 10 μm Hg film carbon fiber disk microelectrode to accumulate f-elements is described. Accumulation was performed by cathodic deposition and evaluated by anodic stripping and subsequent ICPMS analyses. La(3+) was used as the model element, and subsequent studies were conducted on a 17 element mixture (Sc, Y, La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu, and Th). In the model studies, La(3+) undergoes a sorption phenomenon, and as in other studies and confirmed by ICPMS, a monolayer of atoms on the electrode surface is formed. Dissolved O(2) was found to have no effect on the cathodic accumulation of La(3+). Consideration of electrode reaction conditions is made, and reactions are hypothesized. The limit of detection (LOD) was found to be 10(-7) M with mass detection of 10(9) atoms, approximately 5 orders of magnitude less than at conventionally sized electrodes. To solve a dilution problem in follow-on analyses, a suggestion to use microelectrode chip-based sensors was made.

Intra-thoracic pyogranulomatous disease in four working dogs

CASE HISTORY

Four working dogs were presented to veterinary clinics in New Zealand for weight loss or swelling of the thoracic wall. All dogs were large-breed males between the ages of 4 and 7 years, and actively involved in farm work. The two dogs with swelling of the thoracic wall had recent histories of work-related trauma.

CLINICAL FINDINGS AND DIAGNOSIS

All four dogs were diagnosed with intra-thoracic pyogranulomatous disease via diagnostic imaging and surgical exploration. Two dogs had confirmed infection with Actinomyces viscosus, while a third had suspected Actinomyces or Nocardia spp. infection. The fourth dog had a streptococcal infection, and a grass-seed foreign body was removed at surgery. Two dogs successfully returned to work, however euthanasia was requested by the owners of the other two, either during surgery, due to intra-thoracic haemorrhage, or shortly after, with post-operative meningitis.

CLINICAL RELEVANCE

Due to the high value of working dogs in New Zealand, and the higher-than-average risk profile for intra-thoracic pyogranulomatous disease, veterinarians should be aware of this syndrome, and should seek to appropriately diagnose and aggressively treat it surgically.

Interventions implemented through sporting organisations for increasing participation in sport

BACKGROUND

There is now compelling scientific evidence that increased levels of physical activity can bring wide-ranging health benefits. These benefits can extend beyond physical health and include other positive impacts relating to mental health and personal development. The sport and recreation sector is viewed as a priority area for increasing rates of physical activity. Participation rates have been shown to be lower in females, decline with age, and are reduced in lower socio-economic and minority groups. It is important to determine the most effective interventions that sporting organisations can use to increase participation.

OBJECTIVES

To review all controlled evaluation studies of interventions organised through sporting settings to increase participation.

SEARCH STRATEGY

We searched The Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, EMBASE, PsyclNFO, CINAHL, SPORTDiscus, Sociological Abstracts, Dissertation Abstracts, and a number of freely-available online health promotion and sports-related databases. The internet was used extensively to search for studies and locate information generated by sporting bodies throughout the world.

SELECTION CRITERIA

Types of studies: Controlled evaluation studies. No minimum follow-up required. Uncontrolled studies, meeting other inclusion criteria, were to be reported in an annex to the review.

TYPES OF PARTICIPANTS

People of all ages. Types of interventions: Any intervention designed to increase active and/ or non-active participation in sport. These could include: mass media campaigns; information or education sessions; management or organisational change strategies; policy changes, for example to improve the socio-cultural environment to encourage people of specific age, gender or ethnicity to participate; changes to traditional or existing programs, for example club or association-initiated rule modification programs; provision of activities beyond traditional or existing programs, for example 'Come and Try' initiatives (teaser or taster programs); skill improvement programs; volunteer encouragement programs. Types of outcome measures: Change in the number of (active and non-active) participants in organised sport, change in status from non-participating to non-active or active participation, change in status from non-active to active participation.

DATA COLLECTION AND ANALYSIS

We assessed whether identified citations were controlled evaluation studies which investigated the use of interventions implemented in sporting settings to increase participation. Two reviewers independently inspected abstracts. We obtained full papers where necessary. As no controlled evaluation studies were located, no data collection or analysis was undertaken. No uncontrolled studies meeting other inclusion criteria were identified and therefore no annex is presented.

MAIN RESULTS

Despite a thorough review of the published and unpublished literature, we were unable to locate any rigorous studies which tested the effects of interventions organised through sporting organisations to increase participation in sport.

AUTHORS' CONCLUSIONS

There is an absence of high quality evidence to support interventions designed and delivered by sporting organisations to increase participation in sport. Interventions funded and conducted in this area must be linked to a rigorous evaluation strategy in order to examine overall effectiveness, sociodemographic differentials in participation and cost-effectiveness of these strategies.

Interventions implemented through sporting organisations for increasing participation in sport

BACKGROUND

There is now compelling scientific evidence that increased levels of physical activity can bring wide-ranging health benefits. These benefits can extend beyond physical health and include other positive impacts relating to mental health and personal development. The sport and recreation sector is viewed as a priority area for increasing rates of physical activity. Participation rates have been shown to be lower in females, decline with age, and are reduced in lower socio-economic and minority groups. It is important to determine the most effective interventions that sporting organisations can use to increase participation.

OBJECTIVES

To review all controlled evaluation studies of interventions organised through sporting settings to increase participation.

SEARCH STRATEGY

We searched The Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, EMBASE, PsyclNFO, CINAHL, SPORTDiscus, Sociological Abstracts, Dissertation Abstracts, and a number of freely-available online health promotion and sports-related databases. The internet was used extensively to search for studies and locate information generated by sporting bodies throughout the world.

SELECTION CRITERIA

Types of studies: Controlled evaluation studies. No minimum follow-up required. Uncontrolled studies, meeting other inclusion criteria, were to be reported in an annex to the review.

TYPES OF PARTICIPANTS

People of all ages. Types of interventions: Any intervention designed to increase active and/ or non-active participation in sport. These could include: mass media campaigns; information or education sessions; management or organisational change strategies; policy changes, for example to improve the socio-cultural environment to encourage people of specific age, gender or ethnicity to participate; changes to traditional or existing programs, for example club or association-initiated rule modification programs; provision of activities beyond traditional or existing programs, for example 'Come and Try' initiatives (teaser or taster programs); skill improvement programs; volunteer encouragement programs. Types of outcome measures: Change in the number of (active and non-active) participants in organised sport, change in status from non-participating to non-active or active participation, change in status from non-active to active participation.

DATA COLLECTION AND ANALYSIS

We assessed whether identified citations were controlled evaluation studies which investigated the use of interventions implemented in sporting settings to increase participation. Two reviewers independently inspected abstracts. We obtained full papers where necessary. As no controlled evaluation studies were located, no data collection or analysis was undertaken. No uncontrolled studies meeting other inclusion criteria were identified and therefore no annex is presented.

MAIN RESULTS

Despite a thorough review of the published and unpublished literature, we were unable to locate any rigorous studies which tested the effects of interventions organised through sporting organisations to increase participation in sport.

AUTHORS' CONCLUSIONS

There is an absence of high quality evidence to support interventions designed and delivered by sporting organisations to increase participation in sport. Interventions funded and conducted in this area must be linked to a rigorous evaluation strategy in order to examine overall effectiveness, sociodemographic differentials in participation and cost-effectiveness of these strategies.

Divergent human and mouse orthologs of a novel gene (WBSCR15/Wbscr15) reside within the genomic interval commonly deleted in Williams syndrome

Williams syndrome (WS) is a contiguous gene deletion disorder resulting in complex and intriguing clinical features. Detailed molecular characterization studies of the genomic segment on human chromosome 7q11.23 commonly deleted in WS have uncovered numerous genes, each of which is being actively studied for its possible role in the etiology of the syndrome. Our efforts have focused on the comparative mapping and sequencing of the WS region in human and mouse. In previous studies, we uncovered important differences in the long-range organization of these human and mouse genomic regions; in particular, the notable absence of large duplicated blocks of DNA in mouse that are present in human. Aided by available genomic sequence data, we have used a combination of gene-prediction programs and cDNA isolation to identify the human and mouse orthologs of a novel gene (WBSCR15 and Wbscr15, respectively) residing within the genomic segment commonly deleted in WS. Unlike the flanking genes, which are closely related in human and mouse, WBSCR15 and Wbscr15 are strikingly different with respect to their cDNA and corresponding protein sequences as well as tissue-expression pattern. Neither the WBSCR15- nor Wbscr15-encoded amino acid sequence shows a statistically significant similarity to any characterized protein. These findings reveal another interesting evolutionary difference between the human and mouse WS regions and provide an additional candidate gene to evaluate with respect to its possible role in the pathogenesis of WS.

Intracellular gene transfer in action: dual transcription and multiple silencings of nuclear and mitochondrial cox2 genes in legumes

The respiratory gene cox2, normally present in the mitochondrion, was previously shown to have been functionally transferred to the nucleus during flowering plant evolution, possibly during the diversification of legumes. To search for novel intermediate stages in the process of intracellular gene transfer and to assess the evolutionary timing and frequency of cox2 transfer, activation, and inactivation, we examined nuclear and mitochondrial (mt) cox2 presence and expression in over 25 legume genera and mt cox2 presence in 392 genera. Transfer and activation of cox2 appear to have occurred during recent legume evolution, more recently than previously inferred. Many intermediate stages of the gene transfer process are represented by cox2 genes in the studied legumes. Nine legumes contain intact copies of both nuclear and mt cox2, although transcripts could not be detected for some of these genes. Both cox2 genes are transcribed in seven legumes that are phylogenetically interspersed with species displaying only nuclear or mt cox2 expression. Inactivation of cox2 in each genome has taken place multiple times and in a variety of ways, including loss of detectable transcripts or transcript editing and partial to complete gene loss. Phylogenetic evidence shows about the same number (3-5) of separate inactivations of nuclear and mt cox2, suggesting that there is no selective advantage for a mt vs. nuclear location of cox2 in plants. The current distribution of cox2 presence and expression between the nucleus and mitochondrion in the studied legumes is probably the result of chance mutations silencing either cox2 gene.

Origins, colonization, and lineage recombination in a widespread perennial soybean polyploid complex

Polyploidy is a dominant feature of flowering plant genomes, including those of many important crop species, implying that polyploidy confers evolutionary advantages on plant species. Recent molecular studies suggest that polyploids often originate many times from the same progenitor diploids. For this to provide a broader genetic base for a polyploid species, there must be lineage recombination in the genomes of polyploids having different origins, and this has rarely been documented in recently formed wild polyploid species. Glycine tabacina, a wild relative of soybean, forms a widespread polyploid complex in Australia and the islands of the Pacific Ocean. In a sample of 40 G. tabacina plants, DNA sequence variation at one homoeologous histone H3-D locus identified three alleles, each also found in Australian diploid Glycine species. These data agree with our previous studies of chloroplast DNA variation in suggesting that this polyploid has originated several times. Both the origins of the polyploid and several independent dispersals from Australia to oceanic islands appear to have occurred within the last 30,000 years. The distributions of histone alleles, chloroplast haplotypes, and alleles at two isozyme loci were uncorrelated, and 20 multilocus genotypes were found among the 40 plants sampled. Extensive lineage recombination is thus hypothesized in the polyploid, involving migration and occasional outcrossing in this predominantly inbreeding species. The combination of multiple origins with gene exchange among lineages increases the genetic base of a polyploid and may help explain the wide colonization of polyploid G. tabacina relative to its diploid progenitors.

Malignant spindle cell tumor arising in the mandible of a patient with florid osseous dysplasia

Florid osseous dysplasia is a non-neoplastic condition of the alveolar processes of the jaws characterized by the replacement of multiple foci of bone by fibrous connective tissue, accompanied by gradual deposition of cementum, bone, or both. The lesions are not associated with inflammatory diseases of the dental pulp or periodontal tissues. In fully developed florid osseous dysplasia, there are multiple lobulated masses in the alveolar bone bilaterally in the mandible and sometimes in the maxilla. This is the first report of a malignancy originating within the jaws of a patient with florid osseous dysplasia. A spindle cell malignancy was diagnosed in the mandible of a 54-year-old black woman whose jaw was affected by florid osseous dysplasia bilaterally. Despite extensive surgery and radiotherapy, the patient died 20 months after diagnosis of the malignancy.

Incongruence in the diploid B-genome species complex of Glycine (Leguminosae) revisited: histone H3-D alleles versus chloroplast haplotypes

Variation at the single-copy nuclear locus histone H3-D was surveyed in the diploid B-genome group of Glycine subgenus Glycine (Leguminosae: Papilionoideae), which comprises three named Australian species and a number of distinct but as yet not formally recognized taxa. A total of 23 alleles was identified in the 44 accessions surveyed. Only one individual was clearly heterozygous, which is not surprising given the largely autogamous breeding system of subgenus Glycine. Alleles differed by as many as 19 nucleotide substitutions, nearly all in the three introns; length variation was minimal. Phylogenetic analysis identified two shortest allele trees with very little homoplasy, suggesting that recombination has been rare. Both topological and data set incongruence were statistically significant between histone H3-D allele trees and trees inferred from chloroplast DNA haplotypes previously described from these same accessions. Whereas the distribution of H3-D alleles agrees well with morphologically based taxonomic groupings, chloroplast DNA haplotype polymorphisms transgress species boundaries, suggesting that the chloroplast genome is not tracking taxic relationships. Divergences among chloroplast DNA haplotypes involved in such transgressive patterns appear to be more recent than speciation events, suggesting hybridization rather than lineage sorting.

Oral manifestations of systemic diseases

Many systemic diseases have oral manifestations. The oral cavity might well be thought of as the window to the body because oral manifestations accompany many systemic diseases. These oral manifestations must be properly recognized if the patient is to receive appropriate diagnosis and referral for treatment. We have reviewed a series of recent articles and summarized known and newly described oral manifestations of several systemic diseases. The lesions of the oral mucosa, tongue, gingiva, dentition, periodontium, salivary glands, facial skeleton, extraoral skin and other related structures caused by some of the more common systemic diseases are highlighted.

Ataxia, arrhythmia and ion-channel gene defects

Ion channels are essential to a wide range of physiological functions including neuronal signaling, muscle contraction, cardiac pacemaking, hormone secretion and cell proliferation. The important role that highly regulated ion influx plays in these processes has been underscored by a recent flurry of discoveries linking ion-channel gene mutations to inherited disorders. Ion channels of many different types have been demonstrated as being causative factors in genetic disease. This review discusses the growing number of disorders associated with genes of the voltage-gated ion channel superfamily, with special focus on those characterized by neurological, neuromuscular, or cardiac dysfunction in humans and mice.

Genetic analysis of Netrin genes in Drosophila: Netrins guide CNS commissural axons and peripheral motor axons

Two tandem Netrin genes in Drosophila are expressed at the midline of the developing CNS and in different subsets of neurons, muscles, and epidermal patches. In embryos carrying a small deficiency that deletes both genes, CNS axon commissures are partially missing or thinner. This phenotype is rescued by expressing either Netrin gene at the midline. Pan-neural expression of either gene causes disruption of commissural and longitudinal tracts, indicating that the pattern of Netrin expression is crucial and that Netrins function as instructive cues. The double mutant also shows defects in motor axon projections. Expression of either Netrin gene in all muscles also results in aberrant motor projections. Thus, Drosophila Netrins are required for the guidance of commissural axons at the midline, and of motor axons to their target muscles.

The distribution and phylogenetic significance of a 50-kb chloroplast DNA inversion in the flowering plant family Leguminosae

Species in 9 of the approximately 650 genera of the flowering plant family Leguminosae are known to possess a large (50-kb) inversion in their chloroplast genomes, relative to the gene order found most commonly among land plants. Putatively basal elements of the family have not been surveyed for the inversion, which is unknown outside the legumes. Using a combination of polymerase chain reaction and restriction-mapping approaches employing primers or hybridization probes flanking inversion endpoints, 132 legume genera were screened for the presence of the inversion. The inversion was found to be absent in all taxa from two of the three subfamilies (Mimosoideae and Caesalpinioideae), whereas the inversion was found to be present in most taxa of the third subfamily (Papilionoideae). Two papilionoid tribes, Swartzieae and Sophoreae, were heterogeneous for the inversion, which is consistent with a number of lines of evidence suggesting the polyphyly of these tribes. The 50-kb inversion appears to be a unique event in the evolution of Leguminosae, providing a synapomorphy for a clade that includes most of the Papilionoideae.

Identification of axons in the peri-implant region by immunohistochemistry

In the edentulous patient with a completely implant-supported prosthesis, periodontal ligament receptors are absent. However, the implant patient's mandibular function during mastication and clenching is significantly improved and can be similar to that of dentulous subjects. The underlying mechanisms that govern this proprioceptive control are not well understood. One possibility that has been explored only partially is that residual axonal elements in the peri-implant region may have a proprioceptive function. To survey the peri-implant region for axonal elements, this study utilized immunohistochemistry with neurofilament as the marker. Histologic sections of the peri-implant area from 12 implants placed in the mandibles of three dogs were examined for the presence of neurofilament. Two to three labeled sites per section in the peri-implant region were commonly found. However, the functional significance of these axons must be further evaluated before any conclusions regarding their role in proprioception can be made.

Leiomyoma of the oral cavity: a light microscopic and immunohistochemical study with review of the literature from 1884 to 1992

Leiomyoma is the most common benign neoplasm in the uterus and stomach but is rare in the oral cavity. There were only 5 oral cases in a series of 7748 leiomyomas of all sites. Benign smooth muscle neoplasms are classified into leiomyoma (solid leiomyoma), angiomyoma (vascular leiomyoma) and epithelioid leiomyoma (leiomyoblastoma). 6 cases diagnosed as leiomyoma were retrieved from the files of two oral biopsy services over the past 25 years. A light microscopic study including trichrome and phosphotungstic acid haematoxylin (PTAH) stains, and an immunohistochemical study with the following markers: desmin, muscle specific actin, myoglobin, vimentin, S-100 protein, neuron-specific enolase, factor VIII and Ulex europeus were done with suitable controls. The haematoxylin and eosin and Masson's trichrome stains supported a diagnosis of leiomyoma in all 6 cases but PTAH was positive in only 3 of them. The immunohistochemical study confirmed the diagnosis of leiomyoma in 3 cases. The other 3 were identified as granular cell tumour, myofibroma and neurofibroma, respectively. The review of the literature contributed the following data: mean age was 41 and median age 39 in 134/142 patients. A male sex prevalence 72/137 patients (54.0%) was noted. The lips were the most common site with 39 cases (27.46%) followed by the tongue 26 (18.30%), cheeks and palate 22 (15.49%), gingiva 12 (8.45%), and mandible 8 (5.63%). Prognosis of oral leiomyomas is excellent. Immunohistochemistry is a precise and reliable method for definitive diagnosis of oral leiomyoma.

Clear cell odontogenic carcinoma with lymph node metastasis

Clear cell odontogenic tumors are rare. Review of the literature showed 9 cases with a prominent clear cell component. These lesions have exhibited an aggressive behavior characterized by an infiltrative local growth pattern, recurrence, or metastases. We report a case of an odontogenic tumor that exhibited a biphasic pattern and was characterized by lymph node involvement identical histologically to the primary tumor. We conclude that the presence of a clear cell component in an ameloblastomatous tumor should be viewed as a sign of de-differentiation, and that a malignancy with or without metastases should be considered and ruled out in such cases.

Malignant transformation of peripheral ameloblastoma

A peripheral (extraosseous) ameloblastoma was excised from the maxillary left tuberosity of an 82-year-old man. It recurred twice over a 5-year period, once as squamous cell carcinoma and again as undifferentiated carcinoma. Analysis of the literature suggests that peripheral ameloblastomas may have the same potential for malignant transformation as intraosseous ameloblastomas.

Unique odontogenic tumor with dentinogenesis and features of unicystic plexiform ameloblastoma

A case of an atypical odontogenic tumor with features of unicystic plexiform ameloblastoma and odontoblastic differentiation with deposition of tubular dentin matrix is reported. The significance of dentinogenesis, amelogenesis, and calcification in odontogenic tumors is discussed.

Multiple origins of polyploids in the Glycine tabacina complex inferred from chloroplast DNA polymorphism

The Glycine tabacina polyploid complex has been shown to include a minimum of two morphological and crossing groups, which also differ in chloroplast DNA (cpDNA) restriction map and nuclear ribosomal gene repeat phenotype. These AAB2B2 and BBB2B2 G. tabacina polyploids contain plastomes referable to the A and B diploid plastome groups of subgenus Glycine, respectively. Eight different cpDNA variants were observed among the 65 B-type polyploids studied, six of which were identical for numerous restriction site characters to plastome types found among the highly polymorphic B genome diploid species. It is hypothesized that there have been numerous independent origins of polyploid G. tabacina: at least one AA x B2B2 event and a minimum of five BB x B2B2 events involving different BB types as female progenitor. Low amounts of cpDNA divergence between diploid and polyploid plastomes and among the plastomes of geographically disjunct polyploids suggest that the origin and dispersal of polyploids are relatively recent events. All hypothesized diploid progenitors are native to Australia, while both A- and B-type G. tabacina polyploids occur on islands of the Pacific outside the range of diploids. The presence of several different plastome types of polyploid G. tabacina in the Pacific islands suggests that several colonization events have occurred.

Eosinophilic ulcer

A 10-year review of biopsy accessions revealed 15 cases of eosinophilic ulcer. Six manifested recurrent or multiple lesions, and two exhibited histologic atypia. The possible relationships to other oral and systemic diseases are discussed.

Odontogenic ghost cell carcinoma

An unusual malignant odontogenic tumor containing large numbers of ghost cells is described. A 46-year-old white man had an aggressive lesion of the right maxilla, multiple pulmonary nodules developed, and he died 1 year after initial diagnosis. Histologic features included columnar odontogenic epithelium, malignant epithelium, microcysts, masses of ghost cells with focal calcification, and small areas of "dentinoid." The relationship is explored between this tumor and calcifying odontogenic cysts, particularly the "dentinogenic ghost cell tumor" variant.

Odontogenic fibroma of the complex (WHO) type: report of six cases

Six cases of the complex (World Health Organization) type of odontogenic fibroma are described. The relationships of these lesions to the simple type of odontogenic fibroma, desmoplastic fibroma, and to certain reactive lesions are discussed.

Chronic pemphigus vulgaris of the gingiva. A case report with a 6-year follow-up

Since the initial lesions of pemphigus vulgaris often appear in the oral cavity, dentists have a major role in the recognition and diagnosis of this condition. The patient reported here was seen with a mild gingival form of the disease and has been managed successfully for the past 6 years without systemic steroids and with minimal topical steroid therapy. For most of that period he was managed without medication. Various aspects of the disease, including diagnosis, the significance of pemphigus antibodies and therapy are reviewed to provide a better perspective on this case.

Aggressive fibrous histiocytoma of perioral soft tissues: report of case

A rare case of aggressive fibrous histiocytoma is presented to alert the clinician to the existence of such a lesion and its ability to develop as a perioral soft tissue tumor. The research on these lesions clearly demonstrates the lability of their biologic potential. The clinical characteristics, symptoms, and histiologic makeup are reviewed and further reinforce the conclusion that careful microscopic study and thorough longterm followup to adequate surgical treatment are currently the only effective means in the management of these tumors. Continued reports from clinicians and researchers will perhaps satisfy many questions concerning this curious and potentially destructive and lethal group of lesions.

Visceral Kaposi's sarcoma presenting with gingival lesions

This is the first reported case of fatal visceral Kaposi's sarcoma which presented with oral lesions and in which skin lesions were absent throughout the course of the disease. Both clinical and histologic recognition may be difficult because of the similarity of the lesions to pyogenic granuloma.

Intraoral papillary cystadenoma lymphomatosum

The literature related to intraoral papillary cystadenoma lymphomatosum is critically reviewed and the reported cases analyzed to determine the average age, sex, and race of patients, and the site distribution of this curious lesion. Two new cases are reported. The histogenesis and differential diagnosis from cystadenocarcinoma are briefly discussed.

Feulgen microspectrophotometry of oral cancer and leukoplakia

Feulgen microspectrophotometry was performed using the two wavelength method on 33 lesions and showed that five of ten carcinomas and 12 of 16 leukoplakias had diploid cell lines. This correlates well with similar findings in cervical cancer and dysplasia suggesting that changes in nuclear deoxyribonucleic acid content occur quite early in the evolution of cancer.