Radiographic tracheal lumen to vertebral ratios in the normal American Miniature Horse.

BACKGROUND: Tracheal collapse in horses is reportedly uncommon; however, American Miniature Horses are more commonly affected. There is no description of the tracheal luminal diameter of American Miniature Horses, making early detection of tracheal luminal narrowing difficult. OBJECTIVES: To 1) describe radiographic tracheal luminal diameter in clinically normal American Miniature Horses, 2) report the prevalence of subclinical tracheal collapse in a population of American Miniature Horses, and 3) use tracheal videofluoroscopy to quantify variation in tracheal luminal diameter throughout the respiratory cycle in horses with no clinical respiratory disease. STUDY DESIGN: Descriptive observational reference interval study. METHODS: Thirty-four American Miniature Horses with no reported history of respiratory illness were recruited. Lateral cervical and thoracic radiographs were obtained in unsedated standing horses. Dynamic fluoroscopic images were obtained of the cervical and thoracic trachea throughout the respiratory cycle. Horses were then sedated as needed and tracheoscopy was performed. Twenty-nine horses were categorised as normal, and five horses were categorised as subclinically affected based on 25% or greater tracheal narrowing using tracheoscopy for visual assessment. Radiographic tracheal lumen to vertebral body measurements were obtained throughout the cervical and thoracic trachea. Maximum and minimum fluoroscopic tracheal diameter at each site throughout the respiratory cycle was recorded. RESULTS: A mean, median, 95% confidence interval and bootstrapped 95% reference interval of radiographic tracheal diameter to vertebral body ratios were generated in normal horses. The prevalence of subclinical tracheal collapse in this population of American Miniature Horses is 14.7%. MAIN LIMITATIONS: Bootstrapped reference range was generated from 29 horses. CONCLUSIONS: Radiographic tracheal measurements and ratios of the tracheal diameter to vertebral body in the normal American Miniature Horse are described herein and can be used as a guideline when screening for tracheal disease in American Miniature Horses. The prevalence of subclinical tracheal collapse in American Miniature Horses may be higher than previously reported.

Metaphyeal and Diaphyseal Dysplasia of the Third Cervical Vertebra Secondary to Physeal Necrosis in a Quarter Horse Foal.

Ischaemia-induced physeal injury has not been described previously in the horse. A 1-month-old Quarter horse foal was submitted for necropsy examination due to an acute onset of ataxia followed by a 4-week history of progressive decline. Focal narrowing of the spinal canal due to ventral compression by the rotation of the cranial aspect of the third cervical vertebra (C3) was observed. The metaphysis and diaphysis of C3 were markedly shortened and white-tan in colour. Microscopically, there was complete loss of the dorsal compact bone of C3 and replacement of 80% of the physis that runs parallel to the vertebral canal with fibrous tissue and thickened viable trabecular bone. Both cranial and caudal physes of C3 showed widespread bands of coagulative necrosis of the hypertrophic and calcifying zones. Marked bone marrow hypoplasia with slight fibrosis was observed in the metaphyses and diaphysis. There was no evidence of fracture or inflammation. The epiphyses were microscopically unremarkable. It was hypothesized that a regional transient incomplete and possibly multiphasic ischaemia involving the nutrient artery caused necrosis of the physes, resulting in dysplasia of the bone. Ischaemic injury to the physis should be considered in the pathogenesis of focal bone dysplasia in horses.

Patterns of complementary and alternative medicine use among patients undergoing cancer treatment.

This study aimed to assess the prevalence of complementary and alternative medicine (CAM) use in a representative cancer population prior to and within 6 months of diagnosis. A total of 304 newly diagnosed cancer patients from two UK cancer centres completed a postal survey. Of them, 100 patients (32.9%) used CAM before their cancer diagnosis, 59 of these CAM users continued post diagnosis. Twenty-nine individuals who had not used CAM before began to use it after their cancer diagnosis, creating a total of 88 (28.9%) CAM users in this sample. Reasons for not using CAM included lack of interest, lack of information or endorsement from professionals and satisfaction with conventional care. For those using CAM before diagnosis but not afterwards, the most common reason was a lack of expert guidance on what was safe to use. The use of CAM medicines bought from health food and other retail outlets was high. Complementary and alternative medicine use in cancer patients is common and demonstrates a complex pattern, but CAM use is not significantly greater than in the general population. Some patients purchase CAM medicines without seeking medical advice, thus risking drug interactions. Research to generate information on safety and efficacy of CAM is required.

Pernicious anemia and widespread absence of gastrointestinal endocrine cells in a patient with autoimmune polyglandular syndrome type I and malabsorption.

CONTEXT: Autoimmune polyglandular syndrome type I (APS I) is characterized by multiple endocrine gland failures, with other manifestations such as gastrointestinal (GI) symptoms. OBJECTIVE: The objective of the study was to study the histopathological and immunological findings in the GI mucosa of a patient with typical features of APS I, malabsorption, and pernicious anemia. DESIGN AND PATIENT: Biopsies from the GI tract of a patient with APS I were immunostained with chromogranin for GI endocrine cells (GIECs). Blinded slides were graded for numbers of endocrine cells. Normal gastric mucosa was exposed to the patient's serum to test for circulating anti-GIEC and antiparietal cell antibodies using indirect immunofluorescence. SETTING: The study was conducted at the Departments of Pediatrics and Medical Gastroenterology in an academic medical center. RESULTS: The patient's GI mucosa demonstrated absence of GIECs throughout, including gastric gastrin-secreting cells, and her laboratory tests for serum gastrin levels were low normal. Both GIECs and parietal cells were absent in her gastric corpus. The patient's serum contained anti-GIEC antibody but no antiparietal cell antibody. CONCLUSIONS: These observations suggest that GIECs in APS I are subject to an autoimmune destruction that can cause widespread GIEC loss. This could explain the GI dysfunctions that are often noted in the syndrome including malabsorption and atrophic gastric changes with pernicious anemia. We also hypothesize that absence of gastric parietal cells may result mainly from hypogastrinemia that is mainly the loss of gastrin-secreting cells rather than from immune-mediated destruction of parietal cells like that seen in the atrophic gastritis associated with adult-onset pernicious anemia.

The effect of aging and caloric restriction on mitochondrial protein density and oxygen consumption.

It has been proposed that part of the anti-aging mechanism of caloric restriction (CR) involves changes in mitochondrial function. To investigate this hypothesis, mitochondria from various tissues of male Brown Norway rats (fully fed and CR) were isolated and respiration rates determined. In mitochondria from liver, heart, brain and kidney, there were no significant effects of CR on state 4 mitochondrial respiration rate. Further experiments using liver mitochondria under a variety of incubation conditions confirmed that CR does not alter mitochondrial respiration rate in this tissue. However, the respiration rate of mitochondria from brown adipose tissue (BAT) of CR animals was approximately three-fold higher compared to mitochondria from fully fed controls. Mitochondrial protein density was significantly higher in liver tissue of CR animals; it was significantly lower in heart and unchanged in BAT. It is concluded that whilst CR results in tissue-specific changes in mitochondrial respiration rate, these effects do not explain the CR-induced changes in free radical production reported previously for these organelles.

Gastric polyps in pediatrics: an 18-year hospital-based analysis.

OBJECTIVE: Gastric polyps are recognized as either an incidental finding on routine gastroscopy or a frequent occurrence in patients with polyposis syndromes. The aim of this study is to determine the prevalence, clinical presentation, and histological subclassification of gastric polyps identified on esophagogastroduodenoscopy in pediatric patients. METHODS: We performed an 18-yr retrospective study of all pediatric (<21 yr) patients with gastric polyps diagnosed between 1983 and 2000 at The Johns Hopkins Children's Center. The histology slides were all evaluated at the time of the study according to the accepted histological classification of gastric polyps. RESULTS: Gastric polyps were reported in 40 procedures (0.7%) [corrected] performed in 35 (male:female 1.3:1) patients with a mean (SEM) age at diagnosis of 14.4 (0.9) yr. Polyps were more frequent in white than in black patients (adjusted ratio 1.4:1). The histological subtypes included hyperplastic-inflammatory (42%), fundic gland (40%), hamartomatous (10%), adenomatous (5%), and heterotopic polyps (3%). Fundic gland polyps were frequently encountered in patients with familial adenomatous polyposis (81%). These patients tended to be asymptomatic at the time of their surveillance esophagogastroduodenoscopy, and frequently harbored histological changes of either dysplasia (31%) or indeterminate of dysplasia (19%). CONCLUSIONS: Hyperplastic polyps are the most frequently identified gastric polyps in our pediatric population. Fundic gland polyps are common in patients with familial adenomatous polyposis wherein they tend to harbor histological changes of dysplasia. Future longitudinal studies are needed to evaluate the temporal progression of dysplasia to gastric cancer in patients with fundic gland polyps, and to establish esophagogastroduodenoscopy surveillance guidelines.

Characteristics of responding-, nonresponding- and refusing-parents in an adolescent lifestyle choice study.

The acquisition of a random sample is one of the many methodological problems that arise when conducting research with adolescent populations. Frequently, due to ethical considerations associated with collecting data from adolescents, active parental consent procedures are required. The current study examined characteristics of parents who consented, refused consent, or did not respond to an active consent request for their children to participate in a large-scale study of adolescent lifestyle behaviors. Results indicated nonresponding-parents were more likely to be employed than consenting-parents. Further, differences were found for a number of attitudinal variables and about the importance of adolescent research. There were significant differences between refusing-parents, and consenting- and nonresponding-parents who were similar in their attitudes toward adolescent research. The findings suggest that nonresponding-parents are characteristically more similar to consenting-parents than to refusing-parents, which supports the use of passive consent procedures as a reasonable alternative to requiring active parental consent in adolescent research.

Hyperplastic polyps of the esophagus and esophagogastric junction: histologic and clinicopathologic findings.

Hyperplastic polyps of the esophagus and esophagogastric junction region (EGJ) are uncommon lesions characterized by hyperplastic epithelium (foveolar-type, squamous, or both) with variable amounts of inflamed stroma. They have been reported almost exclusively in the radiologic and clinical literature as occurring predominantly in association with gastroesophageal reflux disease (GERD). Comprehensive histologic and clinicopathologic evaluation of these polyps, their association with background mucosal pathology, and their association with Barrett's esophagus has not been previously performed. We studied 30 hyperplastic polyps from 27 patients and characterized the histologic, endoscopic, and clinical features of both the polyps and the background esophagus. Hyperplastic polyps were most common in the region of the EGJ (67%), followed by the distal esophagus (30%) and mid-esophagus (3%). Most (80%) were composed of predominantly cardiac-type mucosa, predominantly squamous mucosa (17%), or an admixture (3%). Intestinal metaplasia of the polyp was present in only 7% and low-grade dysplasia in only 3%. In the majority of cases (67%) hyperplastic polyps were associated with concurrent or recent ulcers or erosive esophagitis. In most cases (48%) esophageal injury was associated with GERD, but other potential etiologies included medications, infection, anastomotic or polypectomy sites, vomiting, and photodynamic therapy. Four patients (15%) had Barrett's esophagus, three of whom had or developed dysplastic Barrett's mucosa. These results underscore the pathogenesis of esophageal/EGJ region hyperplastic polyps as a mucosal regenerative response to surrounding mucosal injury. Careful clinical history and biopsy of the nonpolypoid mucosa are essential for determining the clinicopathologic context in which the polyps have developed.

Missense mutations in COL8A2, the gene encoding the alpha2 chain of type VIII collagen, cause two forms of corneal endothelial dystrophy.

Corneal clarity is maintained by its endothelium, which functions abnormally in the endothelial dystrophies, leading to corneal opacification. This group of conditions includes Fuchs' endothelial dystrophy of the cornea (FECD), one of the commonest indications for corneal transplantation performed in developed countries, posterior polymorphous dystrophy (PPCD) and the congenital hereditary endothelial dystrophies (CHED). A genome-wide search of a three-generation family with early-onset FECD demonstrated significant linkage with D1S2830 (Z(max) = 3.72, theta = 0.0). Refinement of the critical region defined a 6-7 cM interval of chromosome 1p34.3-p32 within which lies the COL8A2 gene. This encodes the 703 amino acid alpha2 chain of type VIII collagen, a short-chain collagen which is a component of endothelial basement membranes and which represented a strong candidate gene. Analysis of its coding sequence defined a missense mutation (gln455lys) within the triple helical domain of the protein in this family. Mutation analysis in patients with FECD and PPCD demonstrated further missense substitutions in familial and sporadic cases of FECD as well as in a single family with PPCD. This is the first description of the molecular basis of any of the corneal endothelial dystrophies or of mutations in type VIII collagen in association with human disease. This suggests that the underlying pathogenesis of FECD and PPCD may be related to disturbance of the role of type VIII collagen in influencing the terminal differentiation of the neural crest derived corneal endothelial cell.

Colchicine toxicity: distinct morphologic findings in gastrointestinal biopsies.

Colchicine is an alkaloid with antimitotic ability used to treat a variety of medical conditions. Colchicine toxicity can result in multiorgan failure and death. The histopathologic features of colchicine toxicity in gastrointestinal biopsies have not been reported. Twenty-one gastrointestinal mucosal biopsies obtained from nine patients receiving oral colchicine therapy were studied. Immunohistochemical staining for Ki67 proliferation antigen was performed, and medical records of each patient were reviewed. All patients had a history of gout. Four patients with chronic renal failure also had clinical evidence of colchicine toxicity, and the other five patients did not. Distinct morphologic changes, seen as metaphase mitoses, epithelial pseudostratification, and loss of polarity, were seen in biopsy material from 4 of 4 (100%) patients with clinical colchicine toxicity. Three of these four cases (75%) also contained abundant crypt apoptotic bodies. These morphologic features were best seen in the biopsies from duodenum and gastric antrum, with relative sparing of the gastric body in the upper gastrointestinal tract. Ki67 staining demonstrated an expansion of the proliferating region in three available cases with clinical colchicine toxicity. These distinctive morphologic features were not seen in the five patients without clinical colchicine toxicity. These results indicate that colchicine toxicity can produce diagnostic morphologic features in gastrointestinal mucosal biopsies. Recognition of these features is important because colchicine toxicity can be fatal if undiagnosed clinically.

Design, synthesis, SAR, and biological evaluation of highly potent benzimidazole-spaced phosphono-alpha-amino acid competitive NMDA antagonists of the AP-6 type.

A series of 2-amino-(phosphonoalkyl)-1H-benzimidazole-2-alkanoic acids was synthesized and evaluated for NMDA receptor affinity using a [3H]CPP binding assay. Functional antagonism of the NMDA receptor complex was evaluated in vitro using a stimulated [3H]TCP binding assay and in vivo by employing an NMDA-induced seizure model. Several compounds of the AP-6 type demonstrated potent and selective NMDA antagonistic activity both in vitro and in vivo. In particular, [R(-)]-2-amino-3-(5-chloro-1-phosphonomethyl-1H-benzoimidazol-2-yl)-propionic acid (1) displayed an IC(50) value of 7.1 nM in the [3H]CPP binding assay and an ED(50) value of 0.13 mg/kg (ip) in the NMDA lethality model. Compound 1, when administered intravenously as a single bolus dose of 3 mg/kg following permanent occlusion of the middle cerebral artery in the rat, reduced the volume of infarcted brain tissue by 45%. These results support a promising therapeutic potential for compound 1 as a neuroprotective agent.

Hyperplastic polyps of the stomach: associations with histologic patterns of gastritis and gastric atrophy.

Hyperplastic polyps are common gastric lesions characterized by hyperplastic foveolae with variable amounts of inflamed stroma. Their pathogenesis is unknown, but they have been reported to occur in association with various forms of chronic gastritis, particularly autoimmune gastritis and Helicobacter pylori gastritis. Comprehensive histologic evaluation of the background mucosal pathology in patients with hyperplastic polyps has not been previously performed. We studied 160 patients with gastric hyperplastic polyps and characterized endoscopic and histologic features of the polyps (i.e., location, multiplicity, and presence of dysplasia and adenocarcinoma) and the background gastric mucosa (i.e., intestinal metaplasia, dysplasia, carcinoma, and presence and classification of gastritis). Hyperplastic polyps were most common in the antrum (60%) and were multiple in 20% of patients. Focal intestinal metaplasia of the polyp was present in 16% and dysplasia in 4% of patients. Only one patient (0.6%) had adenocarcinoma within the polyp. Evaluation of the surrounding gastric mucosa showed at least focal intestinal metaplasia in 37% of patients, adenoma or low-grade flat epithelial dysplasia in 2%, and synchronous or metachronous adenocarcinoma in 6%. Eighty-five percent of patients had inflammatory mucosal pathology, most commonly active chronic H. pylori gastritis (25%), reactive or chemical gastropathy (21%), and metaplastic atrophic gastritis of the autoimmune (12%) or environmental (8%) type. These results indicate a strong association between various forms of gastritis and the development of hyperplastic polyps and further emphasize the importance of biopsy of the nonpolypoid gastric mucosa during endoscopic examination.

Esophageal lichen planus: case report and review of the literature.

Involvement of the esophagus by lichen planus is a rarely reported condition. The histologic features of esophageal lichen planus, which may differ from those of cutaneous disease, have only rarely been illustrated. We describe a 58-year-old woman with skin and oral lichen planus who presented with dysphagia and an esophageal stricture that were ultimately diagnosed as esophageal lichen planus. Multiple esophageal biopsies demonstrated a lichenoid, T cell-rich lymphocytic infiltrate, along with degeneration of the basal epithelium and Civatte bodies. Correct diagnosis of esophageal lichen planus is critical because of its prognostic and therapeutic distinction from other more common causes of esophagitis and stricture formation.

Correction of the influence of baseline artefacts and electrode polarisation on dielectric spectra.

The deconvolution of biological dielectric spectra can be difficult enough with artefact-free spectra but is more problematic when machine baseline artefacts and electrode polarisation are present as well. In addition, these two sources of anomalies can be responsible for significant interference with dielectric biomass measurements made using one- or two-spot frequencies. The aim of this paper is to develop mathematical models of baseline artefacts and electrode polarisation which can be used to remove these anomalies from dielectric spectra in a way that can be easily implemented on-line and in real-time on the Biomass Monitor (BM). We show that both artefacts can be successfully removed in solutions of organic and inorganic ions; in animal cell and microbial culture media; and in yeast suspensions of varying biomass. The high quality of the compensations achieved were independent of whether gold and platinum electrodes were used; the electrode geometry; electrode fouling; current density; the type of BM; and of whether electrolytic cleaning pulses had been applied. In addition, the calibration experiments required could be done off-line using a simple aqueous KCl dilution series with the calibration constants being automatically calculated by a computer without the need for user intervention. The calibration values remained valid for a minimum of 3 months for the baseline model and indefinitely for the electrode polarisation one. Importantly, application of baseline correction prior to polarisation correction allowed the latter's application to the whole conductance range of the BM. These techniques are therefore exceptionally convenient to use under practical conditions.

Crossover breakpoint mapping identifies a subtelomeric hotspot for male meiotic recombination.

Segregation analysis of CEPH and other pedigrees yielded six paternal crossover breakpoints in the approximately 85 kb interval between the minisatellite loci D16S309 (MS205) and D16S83 (EKMDA2) in 16p13.3. Three crossovers were mapped to within the same small (<3 kb) interval, which does not co-localize with any tandem repeat array or expressed sequence. Haplotyping of loci harbouring single nucleotide polymorphism (SNP) markers in this interval confirmed the exchange of flanking markers in the three recombinant individuals. Sequence analysis revealed the presence of recombination-associated motifs and binding sites for the protein translin. Haplotyping of 108 individuals from three European populations at four loci harbouring SNPs showed substantial linkage equilibrium across this interval. Hence molecular and population genetic data are consistent with the presence of an intense male-specific recombination hotspot at this locus.

Synthesis and SAR of adatanserin: novel adamantyl aryl- and heteroarylpiperazines with dual serotonin 5-HT(1A) and 5-HT(2) activity as potential anxiolytic and antidepressant agents.

Several novel functionalized adamantyl aryl- and heteroarylpiperazine derivatives were prepared and examined in various receptor binding and behavioral tests to determine their serotonin receptor activities. Many compounds demonstrated modest to high affinity for 5-HT(1A) receptors, with compounds 9, 13, 23, 33, 34, and 43 being the most potent at this site. Compound 1, 2-[4-(2-pyrimidinyl)-1-piperazinyl]ethyl adamantyl-1-carboxylate, demonstrated relatively high affinity for 5-HT(1A) receptors (K(i) = 8 nM) and acceptable selectivity versus D(2) receptors (K(i) = 708 mM); however, it lacked in vivo activity in serotonergic behavioral models. In contrast, compounds 9 (WY-50,324, SEB-324, adatanserin), adamantyl-1-carboxylic acid 2-[4-(2-pyrimidinyl)-1-piperazinyl]ethylamide, and 13, adamantyl-1-carboxylic acid 2-[4-(2-methoxyphenyl)-1-piperazinyl]ethylamide, demonstrated high affinity for 5-HT(1A) binding sites (K(i) = 1 nM for both) and moderate affinity for 5-HT(2) receptors (K(i) = 73 and 75 nM, respectively). Both compounds also demonstrated partial 5-HT(1A) agonist activity in vivo in rat serotonin syndrome and 5-HT(2) antagonist activity in quipazine- and DOI-induced head shake paradigms. The selective 5-HT(1A) partial agonist and 5-HT(2) antagonist activity of 9 was accompanied by significant anxiolytic activity in an animal conflict model. On the basis of this profile, compound 9 entered development as a combined anxiolytic and antidepressant agent.

Colon stricture and volvulus in a patients with scleroderma.

Gastrointestinal involvement in scleroderma is almost universal. We describe a patient with a benign stricture and volvulus of transverse colon, a life threatening but treatable complication of scleroderma bowel disease. We review the literature on colon volvulus in scleroderma and discuss the importance of recognizing this rare complication.