Discovery of an Oxycyclohexyl Acid Lysophosphatidic Acid Receptor 1 (LPA1) Antagonist BMS-986278 for the Treatment of Pulmonary Fibrotic Diseases

The oxycyclohexyl acid BMS-986278 (33) is a potent lysophosphatidic acid receptor 1 (LPA₁) antagonist, with a human LPA₁ K_b of 6.9 nM. The structure-activity relationship (SAR) studies starting from the LPA₁ antagonist clinical compound BMS-986020 (1), which culminated in the discovery of 33, are discussed. The detailed in vitro and in vivo preclinical pharmacology profiles of 33, as well as its pharmacokinetics/metabolism profile, are described. On the basis of its in vivo efficacy in rodent chronic lung fibrosis models and excellent overall ADME (absorption, distribution, metabolism, excretion) properties in multiple preclinical species, 33 was advanced into clinical trials, including an ongoing Phase 2 clinical trial in patients with lung fibrosis (NCT04308681).

Palaeotopography of a Palaeolithic landscape at Bestwood 1, South Africa, from ground-penetrating radar and magnetometry

In order to investigate the buried landscape at the Fauresmith locality of Bestwood 1, outside the town of Kathu in the Northern Cape Province, we performed ground-penetrating radar and magnetometry surveys across the sand-filled central portion of the valley. The radar images a strong continuous reflector which we can assign to the boundary between the Kalahari sands and underlying Banded Ironstone Formation gravels. Moreover, the thickness of the sand delineates a buried depression in the centre of the valley with flat plateaus at the sides. Subtracting the sand thickness from the current topography produces a map of a small stream channel in the northern part of the valley. Analysis of the magnetic gradient data allows us to extend this buried channel further to the south. Our geophysical survey provides a valuable contribution towards understanding the context of hominin occupation along the banks of a small stream in the Kathu Complex. Significance: • We provide an example of combining two geophysical methods to map overburden thickness, useful for archaeological landscape interpretation.

Discovery of Clinical Candidate BMS-823778 as an Inhibitor of Human 11β-Hydroxysteroid Dehydrogenase Type 1 (11β-HSD-1)

BMS-823778 (2), a 1,2,4-triazolopyridinyl-methanol derived analog, was identified as a potent and selective inhibitor of human 11β-hydroxysteroid dehydrogenase type 1 (11β-HSD-1) enzyme (IC₅₀ = 2.3 nM) with >10,000-fold selectivity over 11β-HSD-2. Compound 2 exhibits robust acute pharmacodynamic effects in cynomolgus monkeys (ED₅₀ = 0.6 mg/kg) and in diet-induced obese (DIO) mice (ED₅₀ = 34 mg/kg). Compound 2 also showed excellent inhibition in an ex vivo adipose DIO mouse model (ED₅₀ = 5.2 mg/kg). Oral bioavailability ranges from 44% to 100% in preclinical species. Its favorable development properties, pharmacokinetics, high adipose-to-plasma concentration ratio, and preclinical pharmacology profile have prompted the evaluation of 2 for the treatment of type 2 diabetes and metabolic syndrome in phase 2 clinical trials.

Discovery of Clinical Candidate 2-((2S,6S)-2-Phenyl-6-hydroxyadamantan-2-yl)-1-(3'-hydroxyazetidin-1-yl)ethanone [BMS-816336], an Orally Active Novel Selective 11β-Hydroxysteroid Dehydrogenase Type 1 Inhibitor

BMS-816336 (6n-2), a hydroxy-substituted adamantyl acetamide, has been identified as a novel, potent inhibitor against human 11β-hydroxysteroid dehydrogenase type 1 (11β-HSD1) enzyme (IC₅₀ 3.0 nM) with >10000-fold selectivity over human 11β-hydroxysteroid dehydrogenase type 2 (11β-HSD2). 6n-2 exhibits a robust acute pharmacodynamic effect in cynomolgus monkeys (ED₅₀ 0.12 mg/kg) and in DIO mice. It is orally bioavailable (%F ranges from 20 to 72% in preclinical species) and has a predicted pharmacokinetic profile of a high peak to trough ratio and short half-life in humans. This ADME profile met our selection criteria for once daily administration, targeting robust inhibition of 11β-HSD1 enzyme for the first 12 h period after dosing followed by an "inhibition holiday" so that the potential for hypothalamic-pituitary-adrenal (HPA) axis activation might be mitigated. 6n-2 was found to be well-tolerated in phase 1 clinical studies and represents a potential new treatment for type 2 diabetes, metabolic syndrome, and other human diseases modulated by glucocorticoid control.

Optimization of 1,2,4-Triazolopyridines as Inhibitors of Human 11β-Hydroxysteroid Dehydrogenase Type 1 (11β-HSD-1)

Small alkyl groups and spirocyclic-aromatic rings directly attached to the left side and right side of the 1,2,4-triazolopyridines (TZP), respectively, were found to be potent and selective inhibitors of human 11β-hydroxysteroid dehydrogenase-type 1 (11β-HSD-1) enzyme. 3-(1-(4-Chlorophenyl)cyclopropyl)-8-cyclopropyl-[1,2,4]triazolo[4,3-a]pyridine (9f) was identified as a potent inhibitor of the 11β-HSD-1 enzyme with reduced Pregnane-X receptor (PXR) transactivation activity. The binding orientation of this TZP series was revealed by X-ray crystallography structure studies.

Functional muscle analysis of the Tcap knockout mouse

Autosomal recessive limb-girdle muscular dystrophy type 2G (LGMD2G) is an adult-onset myopathy characterized by distal lower limb weakness, calf hypertrophy and progressive decline in ambulation. The disease is caused by mutations in Tcap, a z-disc protein of skeletal muscle, although the precise mechanisms resulting in clinical symptoms are unknown. To provide a model for preclinical trials and for mechanistic studies, we generated knockout (KO) mice carrying a null mutation in the Tcap gene. Here we present the first report of a Tcap KO mouse model for LGMD2G and the results of an investigation into the effects of Tcap deficiency on skeletal muscle function in 4- and 12-month-old mice. Muscle histology of Tcap-null mice revealed abnormal myofiber size variation with central nucleation, similar to findings in the muscles of LGMD2G patients. An analysis of a Tcap binding protein, myostatin, showed that deletion of Tcap was accompanied by increased protein levels of myostatin. Our Tcap-null mice exhibited a decline in the ability to maintain balance on a rotating rod, relative to wild-type controls. No differences were detected in force or fatigue assays of isolated extensor digitorum longus (EDL) and soleus (SOL) muscles. Finally, a mechanical investigation of EDL and SOL indicated an increase in muscle stiffness in KO animals. We are the first to establish a viable KO mouse model of Tcap deficiency and our model mice demonstrate a dystrophic phenotype comparable to humans with LGMD2G.

TP53 mutations in malignant and premalignant Barrett's esophagus

In order to improve the efficacy of endoscopic surveillance of Barrett's esophagus, markers of neoplastic progression in addition to dysplasia are required. The aim of the present study was to assess TP53 mutational analysis as a method of identifying patients with Barrett's esophagus who are at greatest risk of adenocarcinoma, for whom endoscopic surveillance is most appropriate. TP53 mutational analysis was initially performed on premalignant and malignant tissue from 30 patients undergoing esophagectomy for adenocarcinoma, and on premalignant biopsies from 48 patients participating in a Barrett's surveillance program. Surveillance patients were followed up endoscopically and histologically for a median of 5 years following TP53 assessment. Mutational analysis was performed by single-strand conformation polymorphism analysis and direct DNA sequencing. TP53 mutations were detected in 10 of 30 esophageal adenocarcinomas, and were more common in well-differentiated carcinomas. An identical TP53 mutation was detected in carcinoma and adjacent dysplasia. Two patients with premalignant Barrett's esophagus had TP53 mutations and one of these patients developed adenocarcinoma on follow up whilst the other has not yet progressed beyond metaplasia. No patient without TP53 mutation developed high-grade dysplasia or adenocarcinoma. TP53 mutations are detected in 33% of esophageal adenocarcinomas and in 4% of premalignant Barrett's esophagus in patients undergoing endoscopic surveillance. TP53 mutation can be detected before the development of high-grade dysplasia or carcinoma, and may be useful in stratifying the risk of adenocarcinoma in patients with Barrett's esophagus.

New classification of oesophageal and gastric carcinomas

Background

The current International Classification of Diseases (ICD)-O classification of carcinomas of the oesophagus and stomach causes epidemiological and clinical confusion, particularly the use of the term cardia and the overlapping subsites described in the stomach. This study compared the epidemiological and clinical features of each subtype and subsite of carcinoma of the oesophagus and stomach to assess requirements for a new classification of these carcinomas.

Methods

Data were extracted with appropriate validity checks on all cases of oesophageal and gastric carcinoma identified throughout the period 1974–1993 by the Merseyside and Cheshire Cancer Registry, which covers a population of 2·5 million. Comparison of all identifiable epidemiological and clinical features of adenocarcinomas at four different subsites, namely the upper two-thirds of the oesophagus, the lower third of the oesophagus, cardia and subcardia of the stomach, was performed.

Results

There were 5322 primary carcinomas of the oesophagus and 10 535 carcinomas of the stomach registered between 1974 and 1993. The incidence of adenocarcinoma of the lower oesophagus and cardia trebled in males and doubled in females, whereas adenocarcinoma of the subcardia region of the stomach declined in both sexes. The incidence of adenocarcinoma of the lower oesophagus and of the cardia was similar for median age at diagnosis, male: female ratio, percentage of patients who smoked, and survival; both were significantly different from values for carcinoma of the subcardia in these respects.

Conclusion

These data suggest that there is considerable overlap between adenocarcinomas of the lower oesophagus and adenocarcinomas currently classified as of the cardia. The authors believe this is due to the group of carcinomas classified as cardia consisting mainly of carcinomas that traverse the gastro-oesophageal junction. These carcinomas were different in all studied parameters from carcinomas of the stomach and should be classified separately from gastric carcinomas. A new subsite classification of oesophageal and gastric carcinomas is proposed that includes the gastro-oesophageal junction as a subsite of the oesophagus and that simplifies the subsite classification of the stomach into proximal, distal and overlapping.

Mucosal ablation in Barrett's esophagus

Barrett's esophagus is a prevalent, premalignant condition affecting the gastroesophageal junction and distal esophagus. Ablation plus antireflux therapy has recently been advocated to prevent the development of adenocarcinoma or to treat those unfit or unwilling to undergo esophagectomy. The present article, based on a search of Medline/ISI databases and cross-referencing of relevant articles, reviews the literature on this subject. A number of techniques have been used to remove the affected mucosa, including laser, electrocoagulation, argon plasma coagulation and photodynamic therapy but, as yet, none has been shown to be superior. Depending on the method used, ablation results in complete removal of Barrett's esophagus in approximately one third of patients and a partial response in nearly two-thirds. The resultant squamous mucosa is apparently 'normal' but may regress. To promote and maintain regeneration, antireflux therapy must be sufficient to reduce repetitive injury to the esophageal mucosa. Whether ablation reduces the cancer risk or delays its occurrence is unknown, though recent data suggests benefit. Complications are infrequent and usually mild. Regular follow-up endoscopy and deep biopsies continue to be necessary. Careful data from much larger populations with long-term follow-up is required before ablation reaches the stage of broad clinical application.

Prevalence of aneuploidy and additional anatomic abnormalities in fetuses and neonates with cleft lip with or without cleft palate: a population-based study in Utah

OBJECTIVE

To determine the prevalence of aneuploidy and additional major anatomic abnormalities in fetuses and neonates with cleft lip with or without cleft palate.

METHODS

All cases of cleft lip with or without cleft palate (cleft lip/cleft palate) occurring in Utah from 1995 through 1999 were reviewed by using the Utah Birth Defect Network population-based surveillance system. All pregnancy outcomes are included (stillborn, live born, and termination) in this analysis.

RESULTS

Of 263 cases of cleft lip/cleft palate, 72 (27.4%) were unilateral cleft lip, 112 (42.6%) were unilateral cleft lip and cleft palate, 12 (4.6%) were bilateral cleft lip, and 67 (25.5%) were bilateral cleft lip and cleft palate. Fifteen (5.7%) of the 263 fetuses and neonates were aneuploid. One (1.2%) with cleft lip (unilateral and bilateral combined) was aneuploid. Five (4.5%) of the fetuses and neonates with unilateral cleft lip and cleft palate were aneuploid compared with 9 (13.4%) of fetuses and neonates with bilateral cleft lip and cleft palate. In known or presumed euploid fetuses and neonates, additional sonographically occult major anatomic abnormalities occurred in 5 (7.0%) of 71 with unilateral cleft lip, 18 (16.8%) of 107 with unilateral cleft lip and cleft palate, 1 (8.3%) of 12 with bilateral cleft lip, and 12 (20.7%) of 58 with bilateral cleft lip and cleft palate. These abnormalities primarily involved the heart and the central nervous system.

CONCLUSIONS

Amniocentesis for karyotype should be offered in all cases of cleft lip/cleft palate because of the risk of aneuploidy. Patients should be counseled that sonographically occult additional anatomic abnormalities might be present with all clefts.

Examination of a CYP2E1 repeat polymorphism in a monkey model of alcohol abuse

BACKGROUND

Cytochrome P-450 2E1 (CYP2E1) is involved in alcohol metabolism, and the expression of this enzyme displays wide phenotypic variability in humans. It has been proposed that some of this variability in expression may be a consequence of the size of a repeat polymorphism in the 5" regulatory region of the gene and that the polymorphism may segregate with alcoholism. This study examined whether the repeat polymorphism exists in macaque monkeys and whether it associates with excessive alcohol consumption in this animal model.

METHODS

Ten outbred cynomolgus monkeys (Macaca fascicularis) that displayed a voluntary alcohol consumption ranging from 1.0 to 3.6 g/kg/day were genotyped for a CYP2E1 repeat polymorphism. This polymorphism has been documented in the region from -2519 base pair (bp) to -1953 bp of the human CYP2E1 gene 5" distal promoter.

RESULTS

Individual polymerase chain reaction amplification of genomic DNA from each of the 10 monkey samples revealed a single band of approximately 400 bp in the region corresponding to the human CYP2E1 polymorphism. Polymerase chain reaction amplicons from the 10 individuals were sequenced, and each one generated a 370 bp sequence that is 90% identical to the human gene sequence. However, unlike human alleles that contain five to eight repeats, the cynomolgus monkey is homozygous for a single copy of the repeat most closely resembling repeat 8 (88% identical) in the human gene.

CONCLUSIONS

These data demonstrate that the CYP2E1 distal promoter region in monkeys is very similar to the human sequence yet lacks the extensive repeated DNA found in humans. This includes the rare repeats 3 and 4, which have been postulated to play a role in transcription regulation and to associate with alcohol abuse liability in humans. These data suggest that the CYP2E1 polymorphism arose late in evolution and that the regulation of the gene by this genetic region is not associated with a heavy alcohol drinking phenotype in the cynomolgus monkey.

Photodynamic therapy and the alimentary tract

Photodynamic therapy offers the possibility of relatively selective tumour necrosis and normal tissue healing. It has many potential applications but as yet no clear role. Articles, editorials and case reports published primarily in English and listed in Medline/ISI up to April 2000 or identified by a manual search have been reviewed in an attempt to provide a comprehensive overview of the use of photodynamic therapy in the alimentary tract. It is concluded that photodynamic therapy can be an effective treatment for superficial pre-malignant mucosal lesions and early cancers, especially in diffuse disease. Suitable patients include those wishing to avoid surgery, high risk subjects or those in whom other forms of treatment have failed. Superiority over other methods of ablation has not so far been demonstrated. Cheaper and more effective photosensitizers and improved techniques of light delivery are likely to increase the application of photodynamic therapy.

Cognitive, linguistic, and social aspects of adults' noun definitions

Low-income, rural adults and middle-income, urban adults provided oral definitions for eight common nouns. Two general issues were addressed: (1) whether the rural adults' definitions would conform to the well-documented Aristotelian form typically found among middle-class, well-educated adults; and (2) whether different definitional types would emerge for two different noun classes, social vs. object nouns. Participants' definitions were examined for conceptual content and linguistic form. Among rural participants, the mean proportion of definitions conforming to the Aristotelian model was .13, contrasted with .69 for the urban participants. Also, rural adults were significantly less likely to cast definitions in the conventional linguistic form than were urban adults. On other measures of definitional skill as well, rural participants demonstrated less mastery. There were no significant differences in definitional form between social and object nouns. Various explanations for the findings are considered.

Interaction of phospholipase D1 with a casein-kinase-2-like serine kinase

Phospholipase D (PLD)1 was phosphorylated in vivo and by an associated kinase in vitro following immunoprecipitation. Both phosphorylation events were greatly reduced in a catalytically inactive point mutant in which the serine residue at position 911 was converted into alanine (S911A). The kinase could be enriched from detergent-extracted brain membranes and bind and phosphorylate PLD1 that was immunoprecipitated from COS-7 cells. Using in-gel kinase assays we determined that the size of the kinase is approximately 40 kDa and that PLD1 is more effective than S911A in binding the kinase. Preliminary analysis of the phosphorylation sites on PLD1 suggested that the kinase belongs to the casein kinase 2 (CK2) family. Consistent with this, we found that the kinase could utilize GTP, and could be inhibited by heparin and 5,6-dichloro-1-beta-D-ribofuranosylbenzimidazole (DRB). Membrane fractions from Chinese hamster ovary (CHO) cell lines that inducibly express PLD1 contained an endogenous kinase activity that phosphorylated PLD1 using GTP and was inhibited by DRB. Direct evidence that the kinase is CK2 came from observations that immunoprecipitates using PLD1 antibodies contained immunoreactive CK2alpha, and immunoprecipitates using CK2alpha antibodies contained immunoreactive PLD1. Co-expression of PLD1 in COS-7 cells with the two recombinant CK2 subunits, alpha or beta, suggests that the association of PLD1 with the kinase is through the beta subunit. Supporting this, phosphorylation of PLD1 by purified recombinant CK2alpha was enhanced by purified recombinant CK2beta. Assays measuring PLD1 catalytic activity following phosphorylation by CK2 suggest that this phosphorylation event does not influence PLD1-mediated hydrolysis of phosphatidylcholine in vitro.

Assessing patient outcomes in acute exacerbations of chronic bronchitis: the measure your medical outcome profile (MYMOP), medical outcomes study 6-item general health survey (MOS-6A) and EuroQol (EQ-5D)

There is little published information on the measurement of health status or quality of life in acute exacerbations of chronic bronchitis. The measure yourself medical outcome profile (MYMOP), the medical outcomes study 6-item general health survey (MOS-6A), and EuroQoL (EQ-5D) were evaluated in 81 patients with acute exacerbations of Type-1 chronic bronchitis presenting at a single general practice centre in Glasgow. The questionnaires were administered at the first clinic visit and at a second visit within 1 week of treatment completion. Item scores for MYMOP were generally more responsive than those for the other instruments, as assessed by standardised response means and an index of responsiveness for those patients reporting minimal change between visits. Construct validity was demonstrated for the MYMOP by the gradient in score change with the patient's perceived change in clinical condition and by the relationship between score change and the physician's assessment of clinical outcome. This study demonstrated that the MYMOP is a valid and potentially useful instrument for the assessment of patient outcomes in acute exacerbations of chronic bronchitis and is more responsive than the MOS-6A or EQ-5D in this setting. The choice of instrument will vary according to the objective of the study.

Sample sizes for cancer trials where Health Related Quality of Life is the primary outcome

Health Related Quality of Life (HRQoL) instruments are increasingly important in evaluating health care, especially in cancer trials. When planning a trial, one essential step is the calculation of a sample size, which will allow a reasonable chance (power) of detecting a pre-specified difference (effect size) at a given level of statistical significance. It is almost mandatory to include this calculation in research protocols. Many researchers quote means and standard deviations to determine effect sizes, and assume the data will have a Normal distribution to calculate their required sample size. We have investigated the distribution of scores for two commonly used HRQoL instruments completed by lung cancer patients, and have established that scores do not have the Normal distribution form. We demonstrate that an assumption of Normality can lead to unrealistically sized studies. Our recommendation is to use a technique that is based on the fact that the HRQoL data are ordinal and makes minimal but realistic assumptions.

Tuberculosis as a cause of chronic epididymo-orchitis in a male caucasian

A69-year-old retired white businessman was referred with a 6-week history of painful swelling of the left side of his scrotum. He had received two courses of broad-spectrum antibiotics from his GP which failed to relieve his symptoms. There was no history of scrotal trauma. There was nothing of note in his past medical history apart from angina and chronic laryngitis. On examination the right side of his scrotum was entirely normal, but the left was tense, tender, warm and approximately three times normal size. A scrotal ultrasound demonstrated a normal left testis with a large hydrocele. The left epididymis was enlarged in it's transverse diameter with high vascularity, consistent with epididymitis.

The patient was started on oral antibiotic therapy. After 1 weeks treatment the left side of the scrotum had reduced slightly in size but remained painful. Eighteen ml of clear fluid was aspirated from the hydrocele and was sent for culture and sensitivity. No organisms were found. By this stage he had been under review for 9 weeks and had taken antibiotics for a total of 24 days. He requested orchidectomy as he felt unwilling to tolerate the discomfort. At operation an abscess cavity was found surrounding the epididymus and extending close to the external ring. Tissue and a swab was sent for culture and sensitivity and for acid-fast bacilli and the left testicle was removed. His postoperative recovery was complicated by a discharging sinus which resolved with irrigation.

The histology report showed extensive areas of necrosis throughout the testis and epididymis with prominent epitheliod cells and many Langhans' type multi-nucleated cells. The appearance was that of florid granulomatous inflammation of the testis and epididymis consistent with a mycobacterium infection. Initial stains for acid-fast bacilli were negative. Subsequently acidfast bacilli were seen in the tissue sample and swabs using oramine phenol counterstained with Ziehl-Nielsen stain. There was a positive culture using Lowenstein Jensen medium, the mycobacteria were sent to a reference laboratory and the species identified as Mycobacterium tuberculosis. He was started on antitubercular treatment. His chest X-ray and intravenous urogram are normal and he remains well 9 months after diagnosis.

Activation of phospholipase D1 by Cdc42 requires the Rho insert region

Members of the Rho subfamily of GTP-binding proteins are implicated in the regulation of phospholipase D (PLD). In the present study, we demonstrate a physical association between a Rho family member, Cdc42, and PLD1. Binding of Cdc42 to PLD1 and subsequent activation are GTP-dependent. Although binding of Cdc42 to PLD1 does not require geranylgeranylation, activation of PLD1 is dependent on this lipid modification of Cdc42. Specific point mutations in the switch I region of Cdc42 abolish binding to and, therefore, activation of PLD1 by Cdc42. Deletion of the Rho insert region, which consists of residues 120-139, from Cdc42 does not interfere with binding to PLD1 but inhibits Cdc42 stimulated PLD1 activity. Interestingly, deletion of the insert region from Cdc42 also inhibits activation of PLD1 by Arf and protein kinase C. With the lack of specific inhibitors of PLD activity, the insert deletion mutant of Cdc42 (designated (DeltaL8)Cdc42) is a novel reagent for in vitro studies of PLD1 regulation, as well as for in vivo studies of Cdc42-mediated signaling pathways leading to PLD1 activation. Because the insert region is required for the transforming activity of Cdc42, regulation of PLD1 by this region on Cdc42 is of major interest.

Genetic polymorphisms of the IL-1alpha and IL-1beta genes in African-American LJP patients and an African-American control population

BACKGROUND

A functional polymorphism of the interleukin-1 beta (IL-1beta) gene has been proposed to be a risk factor for periodontitis. In adult forms of periodontitis, non-smokers of northern European heritage carrying the "2" allele of the IL-1alpha-889 and the IL-1beta +3953 RFLPs in either the heterozygous or the homozygous state at both loci were observed to have a greater risk for developing severe periodontitis. Studies of early-onset periodontitis (EOP) found that allele "1" of both IL-1alpha-889 and IL-1beta +3953 was transmitted more frequently with the EOP phenotype. The purpose of the present study was to determine the prevalence of the IL-1alpha and IL-1beta genotype polymorphisms in an African-American (AA) control population and in 37 African-Americans with localized juvenile periodontitis (LJP).

METHODS

The IL-1alpha +4845 and IL-1beta +3953 loci were genotyped by PCR amplification, followed by restriction enzyme digestion and gel electrophoresis. The IL-1alpha +4845 locus, in linkage disequilibrium (>99%) with IL-1alpha-889, was genotyped because it is technically easier. Data were analyzed using r x c contingency tables.

RESULTS

The IL-1beta +3953 allele "1" was carried by >99% of the AA control population and by 100% of the AA LJP group, with most individuals being homozygous 1,1. The prevalence of the composite genotype with at least one allele "2" at each of the IL-1beta +3953 and IL-1alpha +4845 loci was 14% (AA control group) and 8% (AA LJP group).

CONCLUSIONS

Given the high frequency of the IL-1beta allele "1" in the African-American population, it would appear that knowledge of this +3953 polymorphism would provide little diagnostic or predictive information for LJP.

Histological and molecular mapping of adenocarcinoma of the oesophagus and gastroesophageal junction: loss of heterozygosity occurs in histologically normal epithelium in the oesophagus and stomach

Seventy malignant, premalignant and histologically normal biopsies from 7 oesophagogastrectomy specimens of adenocarcinomas of the lower oesophagus and gastroesophageal junction were analysed for loss of heterozygosity (LOH) at 9 known or putative gene loci. LOH was detected in 20 of 27 (74%) malignant biopsies, 4 of 7 (57%) biopsies of dysplasia, 2 of 12 (25%) biopsies of histologically normal oesophagus adjacent to adenocarcinoma, and in 2 of 14 (14%) biopsies of histologically normal stomach adjacent to adenocarcinoma. LOH at the VHL, APC, CDKN2 and DCC tumour suppressor and MSH3 mismatch repair gene loci can be detected in histologically normal tissue and in adjacent adenocarcinoma, and are potential markers of early neoplastic progression.

LOH at the sites of the DCC, APC, and TP53 tumor suppressor genes occurs in Barrett's metaplasia and dysplasia adjacent to adenocarcinoma of the esophagus

Barrett's esophagus carries a 30- to 100-fold increased risk of adenocarcinoma, which is thought to develop via a metaplasia-dysplasia-carcinoma progression. A common genetic abnormality detected in Barrett's adenocarcinoma is loss of heterozygosity (LOH) at the sites of known or putative tumor suppressor genes, of which there are at least 9 associated with esophageal adenocarcinoma. The aim of this study was to identify at which histological stage of carcinogenesis LOH at these sites occur. Microdissection of multiple paraffin-embedded tissue blocks from 17 esophagogastrectomy specimens of adenocarcinoma arising in Barrett's esophagus yielded areas of metaplasia, low-, intermediate- and high-grade dysplasia, and carcinoma. LOH analysis of microdissected tissues was performed using a double polymerase chain reaction technique with 11 microsatellite primers shown previously to have LOH in at least 30% of esophageal adenocarcinomas. Identical LOH was detected in premalignant and malignant tissues in 4 of 17 patients, and was located at 5q21-q22 (D5S346 primer), 17p11.1-p12 (TCF2 primer), 17p13.1 (TP53 primer), 18q21.1 (detected in colon cancer tumor suppressor gene [DCC] primer), and 18q23-qter (D18S70 primer). These results suggest that LOH at the sites of the DCC, adenomatous polyposis coli (APC), and TP53 tumor suppressor genes occur before the development of adenocarcinoma in Barrett's esophagus, and so merit further study as potential biomarkers of neoplastic progression in patients with Barrett's esophagus undergoing endoscopic and histological surveillance.

Mutations of the cathepsin C gene are responsible for Papillon-Lefèvre syndrome

Papillon-Lefèvre syndrome (PLS) is an autosomal recessive disorder characterised by palmoplantar hyperkeratosis and severe early onset periodontitis that results in the premature loss of the primary and secondary dentitions. A major gene locus for PLS has been mapped to a 2.8 cM interval on chromosome 11q14. Correlation of physical and genetic maps of this interval indicate it includes at least 40 ESTs and six known genes including the lysosomal protease cathepsin C gene (CTSC). The CTSC message is expressed at high levels in a variety of immune cells including polymorphonuclear leucocytes, macrophages, and their precursors. By RT-PCR, we found CTSC is also expressed in epithelial regions commonly affected by PLS, including the palms, soles, knees, and oral keratinised gingiva. The 4.7 kb CTSC gene consists of two exons. Sequence analysis of CTSC from subjects affected with PLS from five consanguineous Turkish families identified four different mutations. An exon 1 nonsense mutation (856C-->T) introduces a premature stop codon at amino acid 286. Three exon 2 mutations were identified, including a single nucleotide deletion (2692delA) of codon 349 introducing a frameshift and premature termination codon, a 2 bp deletion (2673-2674delCT) that results in introduction of a stop codon at amino acid 343, and a G-->A substitution in codon 429 (2931G-->A) introducing a premature termination codon. All PLS patients were homozygous for cathepsin C mutations inherited from a common ancestor. Parents and sibs heterozygous for cathepsin C mutations do not show either the palmoplantar hyperkeratosis or severe early onset periodontitis characteristic of PLS. A more complete understanding of the functional physiology of cathepsin C carries significant implications for understanding normal and abnormal skin development and periodontal disease susceptibility.

Tricho-dento-osseous syndrome and amelogenesis imperfecta with taurodontism are genetically distinct conditions

Amelogenesis imperfecta of the hypomaturation-hypoplasia type with taurodontism (AIHHT) is inherited as a highly penetrant autosomal dominant trait. These dental findings are similar to those of another autosomal dominant condition, the tricho-dento-osseous syndrome (TDO), from which AIHHT differs primarily by lack of changes in the hair and bones. TDO is characterized by a highly variable clinical phenotype. While enamel hypoplasia and taurodontism appear to be present in all TDO cases, non-dental features may be absent, with approximately half of TDO cases losing the kinky/curly hair phenotype seen in infancy by adolescence, and in almost 20% of cases, osseous changes are not evident. The genetic basis for AIHHT is unknown and it has been questioned whether AIHHT and TDO are separate conditions or a spectrum of disease. The genetic basis for TDO has recently been identified as a deletion mutation in the distal-less 3 (DLX3) transcription factor gene. To determine if AIHHT and TDO represent variable expression of a common DLX3 gene mutation, allelic mutations of the DLX3 gene, or mutations in DLX7 (the linked paralogue to DLX3 on chromosome 17), we have performed mutational analysis and sequencing studies of the DLX3 and DLX7 genes in three individuals (two affected and one unaffected) from a family with AIHHT. Results of the analysis demonstrate that AIHHT and TDO are not due to a common DLX3 gene mutation. Sequence analyses of the DLX3 and DLX7 genes suggest AIHHT is not due to genetic mutations or polymorphisms in the exons of these genes. These results suggest that AI-HHT and TDO are two genetically distinct conditions.

Pretherapeutic laparoscopic staging in advanced gastric carcinoma

BACKGROUND AND STUDY AIMS

Direct visualization of the abdominal cavity by laparoscopy prior to multimodal treatment may be capable of improving the diagnostic precision of gastric cancer staging. The aim of this study was to evaluate whether diagnostic laparoscopy can influence treatment strategies in gastric cancer staged T3 and T4 by preoperative diagnostic tests.

PATIENTS AND METHODS

Extended diagnostic laparoscopy (EDL) was carried out in 111 patients with advanced gastric cancer staged T3 or T4 by computed tomography (CT) and endoluminal ultrasound (EUS). On Lauren's classification of gastric cancer, 46% of the lesions were of the intestinal type and 54% of the nonintestinal type. EDL was carried out with the patients under general anesthesia, and included visual inspection of the abdomen, with surgical exploration of initially inaccessible regions, laparoscopic ultrasound examination, peritoneal lavage, and biopsies. The information provided by laparoscopy was classified as 1) no additional information, 2) important additional findings independent of the tumor stage, 3) downgrading of the tumor to a more favorable stage, and 4) upgrading of the tumor to a less favorable stage. The results of EDL were then compared with those obtained by sonography, CT and EUS in combination.

RESULTS

EDL was performed successfully in 107 patients. In 56 of the 111 patients (50.5%), no additional findings were obtained. In 5.4% of cases, additional unforeseen information was found, not connected with the tumor but altering the management. EDL altered the preoperative diagnosis in 51 of the 111 patients (46.0%), leading to changes in management in 45 of them (40.5%). EUS provided additional information in eight cases (7.2% of the whole group, or 15.7% of those in whom the diagnosis had to be changed). Four metastases were detected using EDL. It was possible to rule out peritoneal spread in four patients, but it was newly detected in 26.

CONCLUSIONS

Additional information by EDL about the tumor stage in gastric cancer led to a modification of the therapeutic strategy in 40% of patients, in spite of earlier comprehensive diagnostic work-up using modern imaging procedures. EDL should therefore be mandatory if neoadjuvant treatment is planned, in order to avoid either undertreatment or overtreatment of this type of tumor.

Hyperalgesia due to nerve damage: role of nerve growth factor

The hypothesis that nerve growth factor (NGF) and brain-derived neurotrophic factor (BDNF) contribute to hyperalgesia resulting from nerve damage was tested in rats in which the sciatic nerve was partially transected on one side. Administration of antisera raised against NGF and BDNF relieved mechanical and thermal hyperalgesia in these animals. It has been suggested that NGF may elicit hyperalgesia by inducing mast cells to release algesic agents such as serotonin (5-HT). We found that degranulation of mast cells with compound 48/80 relieved mechanical and thermal hyperalgesia produced by nerve damage. We also found that local injection of the 5-HT2A and 5-HT3 receptor antagonists ketanserin and ICS 205-930 into the affected hind paw relieved mechanical hyperalgesia in a dose-dependent fashion. These findings support the idea that in this rat model of hyperalgesia due to peripheral nerve damage, NGF acts on mast cells to induce release of 5-HT, which sensitizes nociceptors. Hyperalgesia due to nerve injury and hyperalgesia due to inflammation may share some common features.

New classification of oesophageal and gastric carcinomas derived from changing patterns in epidemiology

The current ICD-O classification of carcinomas of the oesophagus and stomach causes epidemiological and clinical confusion. This study compares the epidemiological and clinical features of each subtype and subsite of adenocarcinomas of the oesophagus and stomach, to assess requirements for a new classification of these carcinomas. Data were extracted with appropriate validity checks on all cases of oesophageal and gastric carcinomas identified throughout the period 1974-1993 by the Merseyside and Cheshire Cancer Registry, which covers a population of 2.5 million. The incidence of adenocarcinomas of the lower oesophagus and cardia trebled in males, and doubled in females, whereas adenocarcinoma of the subcardia region of the stomach declined in both sexes. Adenocarcinomas of the lower oesophagus and of the cardia were similar for median age at diagnosis, male to female ratio, percentage of patients who smoked and survival; both were significantly different from carcinomas of the subcardia in these respects. These data imply that adenocarcinomas of the lower oesophagus and cardia are the same disease. A new subsite classification of oesophageal and gastric carcinomas is proposed that includes the gastro-oesophageal junction as a distinct subsite, to facilitate surveillance, management and research.

Quantitative RT-PCR: pitfalls and potential

Reverse transcription PCR (RT-PCR) represents a sensitive and powerful tool for analyzing RNA. While it has tremendous potential for quantitative applications, a comprehensive knowledge of its technical aspects is required. Successful quantitative RT-PCR involves correction for experimental variations in individual RT and PCR efficiencies. This review addresses the mathematics of RT-PCR, choice of RNA standards (internal vs. external) and quantification strategies (competitive, noncompetitive and kinetic [real-time] amplification). Finally, the discussion turns to practical considerations in experimental design. It is hoped that this review will be appropriate for those undertaking these experiments for the first time or wishing to improve (or validate) a technique in what is frequently a confusing and contradictory field.

Allelotype analysis of oesophageal adenocarcinoma: loss of heterozygosity occurs at multiple sites

Deletions of tumour-suppressor genes can be detected by loss of heterozygosity (LOH) studies, which were performed on 23 cases of adenocarcinoma of the oesophagus, using 120 microsatellite primers covering all non-acrocentric autosomal chromosome arms. The chromosomal arms most frequently demonstrating LOH were 3p (64% of tumours), 5q (45%), 9p (52%), 11p (61%), 13q (50%), 17p (96%), 17q (55%) and 18q (70%). LOH on 3p, 9p, 13q, 17p and 18q occurred mainly within the loci of the VHL, CDKN2, Rb, TP53 and DCC tumour-suppressor genes respectively. LOH on 5q occurred at the sites of the MSH3 mismatch repair gene and the APC tumour-suppressor gene. 11p15.5 and 17q25-qter represented areas of greatest LOH on chromosomes 11p and 17q, and are putative sites of novel tumour-suppressor genes. LOH on 9p was significantly associated with LOH on 5q, and tumours demonstrating LOH at both the CDKN2 (9p21) and MSH3 (5q11-q12) genes had a significantly higher fractional allele loss than those retaining heterozygosity at these sites. Six of nine carcinomas displaying microsatellite alterations also demonstrated LOH at CDKN2, which may be associated with widespread genomic instability. Overall, there are nine sites of LOH associated with oesophageal adenocarcinoma.

New Zealand epidemic of meningococcal disease identified by a strain with phenotype B:4:P1.4

New Zealand is experiencing an epidemic of serogroup B meningococcal disease, which has taken the rate of disease from an average of 1.5/100,000 population in the preepidemic years of 1989 and 1990 to 14.0/100,000 in 1996. Sterile-site isolates of Neisseria meningitidis from cases of invasive disease have been phenotypically characterized by serogrouping, serotyping, and serosubtyping, revealing the involvement of a strain with phenotype B:4:P1.4. Macrorestriction analysis using pulsed-field gel electrophoresis on 667 meningococci isolated from cases during the epidemic has identified the clonal relationship of meningococci expressing the PorA P1.4 antigen. Multilocus enzyme electrophoresis has shown the epidemic strain B:4:P1.4 to belong to lineage III. The recorded characteristics of New Zealand's epidemic are consistent with previous serogroup B epidemics in other parts of the world.

Review article: controversy in the therapy of gastro-oesophageal reflux disease--long-term proton pump inhibition or laparoscopic anti-reflux surgery?

The treatment of gastro-oesophageal reflux disease is controversial. Whilst medical treatment is successful in patients with mild to moderate disease, the threshold of severity above which an operation should be contemplated remains a matter for debate. Laparoscopic anti-reflux surgery may be lowering this threshold, as this form of therapy provides several advantages over its open counterpart, but it is not without risk, and few long-term results are available. This article reviews treatment options for reflux disease and examines the relative position of current medical and surgical therapies.

Spigelian herniae: presentation, diagnosis and treatment

A personal series of 19 patients (8 males), mean age 62.4 years (range 21-83 years) with a spigelian hernia [right-sided in eight patients (42.1%)] is presented. The defect was confirmed in 18 patients undergoing surgery, extending between the internal and external oblique layers in 15 of those 18 patients (83.3%) and passing through the external oblique layer in three of the 18 (16.7%). Four uncommon variants were encountered in these 18 patients. The sac was empty in six (33.3%), contained small bowel in six (33.3%), greater omentum in five (27.8%), caecum in one (5.6%) and sigmoid colon in one (5.6%). Four of 19 patients (21.1%) presented acutely with a tender irreducible mass. Thirteen of 19 patients (68.4%) presented electively. All had a palpable swelling which was reducible in 11 of these 13 (84.6%). Local pain and tenderness was inconstant. A spigelian hernia was an incidental finding in two of the 19 patients (10.5%). In only nine out of 17 patients (52.9%) was the diagnosis suspected pre-operatively, and treatment was frequently delayed. Predisposing factors were present in 15 of the 19 patients (78.9%).

Acute appendicitis: does removal of a normal appendix matter, what is the value of diagnostic accuracy and is surgical delay important?

A prospective study with long-term follow-up was undertaken of 248 patients (137 males, median age 18 years (range 6-81 years), undergoing emergency appendicectomy during a 12-month period. Acute inflammation was present in 182 patients (73.4%) (males 86.1%, females 57.8%; P < 0.001). Before surgery, the positive predictive value of diagnostic accuracy was 82.0% (males 91.2%, females 67.7%). Delaying surgery did not significantly increase the proportion of perforated appendices (22.0%), hospital stay, or frequency of postoperative complications (overall 49.6%). Hospital complications were significantly more common among patients with a perforated appendix. There was no significant difference in the complication rate between patients with or without appendicitis while in hospital, during the first 18 months after operation or 8 years after operation. At 18 months, 17 of 238 patients (7.1%) continued to experience their original pain. After 8 years the original pain was still present in 10 of 155 patients (6.5%). Continued pain was more likely in patients having undergone removal of a normal appendix (P < 0.001)

A carboxyl terminal leucine zipper is required for tyrosine hydroxylase tetramer formation

Tyrosine hydroxylase catalyzes the rate-limiting reaction in the biosynthesis of the catecholamine neurotransmitters and hormones (dopamine, norepinephrine, and epinephrine). Rat tyrosine hydroxylase exists, in its native form, as a tetramer composed of identical 498 amino acid subunits. There is currently no information describing the molecular interactions by which the four monomeric tyrosine hydroxylase subunits assemble into an active tetramer. Mutational analysis was performed on bacterially expressed enzyme to assess the role of a putative C-terminal leucine zipper in the assembly of subunits into the tetrameric holoenzyme. Deletion of the C-terminal 19 amino acids, or mutation of a leucine residue (to an alanine), converts the enzyme from a tetrameric to a dimeric form that exhibits greater structural heterogeneity. This change in macromolecular form is accompanied by a 75% (deletion mutation) to 20% (Leu-->Ala mutation) reduction in specific activity of the enzyme. This represents the first report of the functional involvement of a region containing a leucine zipper motif in the assembly and activity of a neuronal enzyme.

Mathematical modelling of the growth, survival and death of Yersinia enterocolitica

This paper discusses the development of a novel mathematical equation capable of handling the growth, survival and death of microorganisms. The equation was used in combination with second-order polynomials to fit a response surface to data representing the growth, survival and death of Yersinia enterocolitica as affected by temperature (0-30 degrees C), sodium chloride (0-10.5% w/v), pH (3.5-7.0) and undissociated lactic acid (0-9.63 g/l). The resulting predictive model showed a good correlation over the entire range of the experimental data. Predictions from the model have been compared with independent data from both published literature and inoculated food studies. Analysis of the results showed a good correlation, particularly for data from milk and meat products.

Catalytic core of rat tyrosine hydroxylase: terminal deletion analysis of bacterially expressed enzyme

Tyrosine hydroxylase (TH) catalyzes the rate-limiting step in catecholamine biosynthesis. This enzyme is hypothesized to consist of an amino-terminal regulatory domain and a carboxy-terminal catalytic domain. In the present studies, we have utilized recombinant DNA techniques to map the boundaries of the regulatory and catalytic domains of TH. We have isolated a full-length cDNA clone for rat pheochromocytoma TH and have expressed the enzyme in bacteria. Utilizing this bacterial expression system and polymerase chain reaction technology, we have constructed and subcloned genes for five amino-terminal deletion mutants (N delta 40, N delta 155, N delta 165, N delta 175 and N delta 200; N delta denotes amino-terminal deletion and the numerical value denotes the number of amino acids deleted) and two carboxy-terminal deletion mutants (C delta 19 and C delta 50). The catalytic core of rat tyrosine hydroxylase has been identified to include the region from amino acid #165 to amino acid #479. The amino-terminal deletion mutants, N delta 40, N delta 155 and N delta 165 are from 1.85 to 2.5-fold more active than unmodified recombinant TH, while the removal of 19 amino acids from the C-terminus (C delta 19) results in a 70% reduction in enzyme activity. Removal of additional sequences (ten more residues from the N-terminus [N delta 175]; or an additional 31 amino acids from the C-terminus [C delta 50]) results in protein that is totally without enzyme activity. As expected, removal of 40 (or more) N-terminal amino acids abolishes the ability of the catalytic subunit of the cAMP-dependent protein kinase to phosphorylate the recombinant enzyme; serine-40 is the phosphorylation site on TH for PKA. We conclude that the N-terminal boundary for the TH catalytic domain resides between residues 165 and 175 and that removal of this N-terminal domain (totally or partially) increases the activity of the enzyme. These findings confirm previous reports that proteolytic cleavage at amino acid #158 produces an active (and activated) catalytic fragment.

Inverse electrocardiographic transformations: dependence on the number of epicardial regions and body surface data points

The inverse problem of electrocardiography, the computation of epicardial potentials from body surface potentials, is influenced by the desired resolution on the epicardium, the number of recording points on the body surface, and the method of limiting the inversion process. To examine the role of these variables in the computation of the inverse transform, Tikhonov's zero-order regularization and singular value decomposition (SVD) have been used to invert the forward transfer matrix. The inverses have been compared in a data-independent manner using the resolution and the noise amplification as endpoints. Sets of 32, 50, 192, and 384 leads were chosen as sets of body surface data, and 26, 50, 74, and 98 regions were chosen to represent the epicardium. The resolution and noise were both improved by using a greater number of electrodes on the body surface. When 60% of the singular values are retained, the results show a trade-off between noise and resolution, with typical maximal epicardial noise levels of less than 0.5% of maximum epicardial potentials for 26 epicardial regions, 2.5% for 50 epicardial regions, 7.5% for 74 epicardial regions, and 50% for 98 epicardial regions. As the number of epicardial regions is increased, the regularization technique effectively fixes the noise amplification but markedly decreases the resolution, whereas SVD results in an increase in noise and a moderate decrease in resolution. Overall the regularization technique performs slightly better than SVD in the noise-resolution relationship. There is a region at the posterior of the heart that was poorly resolved regardless of the number of regions chosen. The variance of the resolution was such as to suggest the use of variable-size epicardial regions based on the resolution.

Acute rheumatic fever in Auckland, New Zealand: spectrum of associated group A streptococci different from expected

Annual specific rates for acute rheumatic fever (ARF) in Auckland children less than 15 years were 22/100,000 for the years 1980 to 1984. From 1984 to 1992 the rates remained relatively constant with an average of 45 (range, 30 to 70) children annually admitted with ARF to the Auckland Children's Hospital. This study examined retrospectively Group A streptococci identified from hospitalized pediatric patients during these 9 years. The total of 2410 isolates included 32 isolates from well-documented cases of ARF and an additional 6 from siblings of cases. Results of M typing indicated that streptococci associated with ARF are generally different from those described overseas and involved types which cause more skin than throat infections in the community.

A phase II study of mitomycin, ifosfamide and cisplatin in operable and inoperable squamous cell carcinoma of the oesophagus

We have evaluated the effect of mitomycin 6 mg/m2, ifosfamide 3 g/m2, and cisplatin 50 mg/m2 (MIC) in two groups of patients with squamous or undifferentiated carcinoma of the oesophagus, as either preoperative or primary treatment. Response was assessed by barium swallow, CT scan, and measurement of metastases where present. Toxicity was acceptable and there were no chemotherapy related deaths. In the operated group, five of 23 patients (22%) showed a complete response (three confirmed histologically) and nine (39%) showed a partial response following two courses of MIC. Resection was completed in 21 patients, with three hospital deaths (14%). Of the 18 patients who were discharged from hospital, eight have died at 4-24 months (median 13) from the start of treatment and 10 are alive at 5-35 months, with known recurrence in one. In the non-operated group, five of 20 patients (25%) showed a response, one complete, following one to four (mean 2.6) courses of MIC. Nineteen patients have died (at median 5 months), and one, who had a complete response, is alive and free from disease at 29 months. Neo-adjuvant therapy with MIC in squamous carcinoma of the oesophagus has shown encouraging early results, with acceptable toxicity.