The genetics of cholesteatoma. A systematic review using narrative synthesis.

OBJECTIVE: A cholesteatoma is a mass of keratinising epithelium in the middle ear. It is a rare disorder that is associated with significant morbidity, and its causative risk factors are poorly understood; on a global scale, up to a million people are affected by this each year. We have conducted a systematic literature review to identify reports about the heritability of cholesteatoma or any constitutional genetic factors that may be associated with its aetiology. DATA SOURCES: A systematic search of MEDLINE (EBSCO) and two databases of curated genetic research (OMIM and Phenopedia) was conducted. STUDY SELECTION: The participants and populations of interest for this review were people treated for cholesteatoma and their family members. The studies of interest reported evidence of heritability for the trait, or any association with congenital syndromes and particular genetic variants. DATA EXTRACTION: The searches identified 449 unique studies, of which 35 were included in the final narrative synthesis. DATA SYNTHESIS: A narrative synthesis was conducted, and data were tabulated to record characteristics, including study design, genetic data and author conclusions. Most of the studies identified in the literature search, and described here, are case reports and so represent the lowest level of evidence. In a few case reports, congenital and acquired cholesteatomas have been shown to segregate within families in the pattern typical of a monogenic or oligogenic disorder with incomplete penetrance. Evidence from syndromic cases could suggest that genes controlling ear morphology may be risk factors for cholesteatoma formation. CONCLUSIONS: This is the first systematic review about the genetics of cholesteatoma, and we have identified a small body of relevant literature that provides evidence of a heritable component for its aetiology. Cholesteatoma is a complex and heterogeneous clinical phenotype, and it is often associated with chronic otitis media and with some rare congenital syndromes known to affect ear morphology and related pathologies.

Randomized clinical trial of folate supplementation in patients with peripheral arterial disease.

BACKGROUND: The aim was to determine whether folate supplementation improved arterial function in patients with peripheral arterial disease (PAD). METHODS: Individuals with PAD were randomly assigned to receive 400 microg folic acid (45 patients) or 5-methyltetrahydrofolate (5-MTHF) (48) daily, or placebo (40) for 16 weeks. Primary endpoints were changes in plasma total homocysteine (tHcy), ankle : brachial pressure index (ABPI) and pulse wave velocity (PWV). Secondary outcomes were changes in plasma inflammatory markers. RESULTS: Plasma tHcy was significantly reduced in folic acid and 5-MTHF groups compared with controls: median difference: - 2.12 (95 per cent confidence interval - 3.70 to - 0.75) micromol/l (P = 0.002) and - 2.07 (-3.48 to - 0.54) micromol/l (P = 0.007) respectively. ABPI improved significantly: median difference 0.07 (0.04 to 0.11) (P < 0.001) and 0.05 (0.01 to 0.10) (P = 0.009) respectively. Brachial-knee PWV (bk-PWV) decreased significantly in individuals receiving 5-MTHF and tended to be reduced in those taking folic acid compared with controls: median difference: - 1.10 (-2.20 to - 0.20) m/s (P = 0.011) and - 0.90 (-2.10 to 0.00) m/s (P = 0.051) respectively. Plasma levels of inflammatory markers were not affected. CONCLUSION: Folate administration reduced plasma homocysteine, and slightly improved ABPI and bk-PWV.

Homocysteine and peripheral arterial disease: systematic review and meta-analysis.

OBJECTIVE: To evaluate homocysteine (Hcy) levels in patients with peripheral arterial disease (PAD) as compared to unaffected controls, and to review the clinical effects of therapy aimed at lowering homocysteine in PAD patients. METHODS: MEDLINE, EMBASE and Cochrane databases were searched from 1950 to December 2007. We selected observational studies and trials that evaluated Hcy levels in patients with PAD compared to unaffected controls. We also included trials on the effect of Hcy-lowering therapy (folate supplementation) in PAD patients. Continuous outcomes were pooled in a random effects meta-analysis of the weighted mean difference between comparator groups. RESULTS: We retrieved 33 potentially suitable articles from our search. Meta-analysis of 14 relevant studies showed that Hcy was significantly elevated (pooled mean difference +4.31micromoll; 95% C.I. 1.71, 6.31, p<0.0001 with significant heterogeneity) in patients with PAD compared to controls. As all 14 studies consistently demonstrated raised plasma Hcy levels in PAD patients, the significant heterogeneity in this meta-analysis probably arises from differences in the degree of Hcy elevation. The effect of folate supplementation on PAD was tested in eight clinical trials but clinically important end points were inconsistently reported. CONCLUSION: Patients with PAD have significantly higher Hcy levels than unaffected controls. However, we did not find any robust evidence on clinically beneficial effects of folate supplementation in PAD.

Clinicopathological features and molecular markers of breast cancer in Jos, Nigeria.

BACKGROUND: Several studies have suggested that breast cancer in black women is associated with aggressive features and poor survival. This study examines molecular markers along with clinical stage and pathological grade in breast cancer material from Jos, Nigeria. STUDY DESIGN: The histological diagnoses of 178 consecutive Nigerian patients with breast cancer were retrieved from their hospital records. A subset of 36 patients was staged and their tumours typed and graded. Immunohistochemical staining of sections from paraffin wax embedded tissues from these cases for the expression of oestrogen receptor (ER), progesterone receptor (PGR), Human ERBB2 (or HER2/neu), p53 and cyclin D1 (CCND1) was carried out using the avidin biotin complex (ABC) procedure. RESULTS: A majority of the cases were invasive ductal carcinoma (92.7%), high grade (grade 3, 70.6%) and of late clinical stage (stages III and IV, 58.3%). Only 25% and 27.8% of cases expressed ER and PGR respectively. The ERBB2 and CCND1 antigens were expressed in 25%, and 5.7% of cases respectively. The p53 protein was the most frequently expressed in this study (47.2% of cases). High grade tumours were significantly more likely to be ER and PGR negative (P = 0.006 and P = 0.002 respectively). CONLCLUSION: There is predominance of high grade, invasive ductal carcinomas which are likely to be ER and PGR negative but p53 positive. These features suggest a biologically aggressive form of breast cancer in Nigerian women with the possibility of poor response to both hormonal therapy and chemotherapy.

A novel germ line juxtamembrane Met mutation in human gastric cancer.

Activating mutations in the Met receptor tyrosine kinase, both germline and somatic, have been identified in human papillary renal cancer. Here we report a novel germline missense Met mutation, P1009S, in a patient with primary gastric cancer. The dosage of the mutant Met DNA was elevated in the tumor when compared to its matched normal DNA. Therefore, as with hereditary renal papillary cancer, the mutant Met allele may also be selectively duplicated in the tumor. Different from previously reported Met mutations, which occur in the tyrosine kinase domain, this missense mutation is located at the juxtamembrane domain, and is not constitutively activated. However, following treatment with HGF/SF, the P1009S mutant Met protein, expressed in NIH3T3 cells, displays increased and persistent tyrosine phosphorylation compared to the wild-type Met. Importantly, these cells also form colonies in soft agar, and are highly tumorigenic in athymic nude mice. A second nucleotide change in this region of Met, T1010I, was found in a breast cancer biopsy and a large cell lung cancer cell line. Although this previously reported 'polymorphism' did not stimulate NIH3T3 cell growth in soft agar, it was more active than the wild-type Met in the athymic nude mice tumorigenesis assay, suggesting that it may have effects on tumorigenesis. Met has been shown to be highly expressed in human gastric carcinoma cell lines, and our results raise the possibility that activating missense Met mutations could contribute to tumorigenesis of gastric cancer.

Lipase-catalyzed modification of rice bran oil to incorporate capric acid.

Capric acid (C10:0) was incorporated into rice bran oil with an immobilized lipase from Rhizomucor miehei as the biocatalyst. Effects of incubation time, substrate mole ratio, enzyme load, and water addition on mole percent incorporation of C10:0 were studied. Transesterification was performed in an organic solvent, hexane, and under solvent-free condition. Pancreatic lipase-catalyzed sn-2 positional analysis and tocopherol analysis were performed before and after enzymatic modification. Products were analyzed by gas-liquid chromatography (GLC) for fatty acid composition. After 24 h of incubation in hexane, there was an average of 26.5 +/- 1.8 mol % incorporation of C10:0 into rice bran oil. The solvent-free reaction produced an average of 24.5 +/- 3.7 mol % capric acid. In general, as the enzyme load, substrate mole ratio, and incubation time increased, the mole percent of capric acid incorporation also increased. Time course reaction indicated C10:0 incorporation increased up to 27.0 mol % at 72 h, for the reaction in hexane, and up to 29.6 mol % at 12 h, for the solvent-free reaction. The highest C10:0 incorporations (53.1 and 43.2 mol %) for the mole ratio experiment occurred at a mole ratio of 1:8 for solvent and solvent-free reactions, respectively. The highest C10:0 incorporation (27.9 mol %) for the reaction in hexane occurred at 10% enzyme load, and the highest incorporation (34.4 mol %) for the solvent-free reaction occurred at 20% enzyme load. Incorporation of C10:0 into rice bran oil declined with the addition of increasing amounts of water after reaching 30.3 mol % at 2% water addition in hexane, and in the solvent-free reaction after reaching 35.9 mol %.

Predictors of 30-day hospital readmission after coronary artery bypass.

BACKGROUND: Risk factors for 30-day hospital readmission following coronary artery bypass grafting (CABG) have not been established. METHODS: We prospectively followed 485 consecutive patients who underwent isolated primary CABG at our institution in 1997. Patients were contacted by telephone at 30 days following operation to determine readmission status. RESULTS: The overall readmission rate was 16% (76 of 485). Female gender (25% versus 11%, p = 0.001) and diabetes (22% versus 12%, p = 0.005) were associated with significantly higher readmission rates. The relationship between female gender and readmission persisted after correcting for age and other comorbidities. Congestive heart failure trended towards a significant relationship with increased readmission rate (22% versus 14%, p = 0.09). There were no significant associations between 30-day readmission rate and age, hypertension, chronic obstructive pulmonary disease, history of myocardial infarction, peripheral vascular disease, creatinine level of > or = 1.4 mg/dL, or decreased left ventricular ejection fraction (< 40%). CONCLUSIONS: These data show that most of the classic risk factors for postoperative mortality are not necessarily associated with increased readmission. However, female gender and diabetes are associated with greater than twice the risk of 30-day readmission following CABG.

The effects of chronic absence of active nasal respiration on the growth of the skull: a pilot study.

Oral respiration associated with an obstructed nasal airway is common in orthodontic patients. For several years chronic oral respiration has been implicated as a prime causative factor in the development of "adenoid facies or the "long-face syndrome. The animal experiment reported here begins a series designed to study, as separate variables, the 2 components of chronic oral respiration: (1) chronic absence of active nasal respiration and 2) chronic mouth opening to find out what dentofacial changes can be attributed to chronic absence of active nasal respiration alone. In this pilot study, 5 growing dogs underwent tracheotomy so that significant active nasal respiration was not possible and oral respiration was not essential.

Screening for diabetic retinopathy using computer based image analysis and statistical classification.

Diabetic retinopathy is one of the most common causes of blindness in Europe. However, efficient therapies do exist. An accurate and early diagnosis and correct application of treatment can prevent blindness in more than 50% of all cases. Digital imaging is becoming available as a means of screening for diabetic retinopathy. As well as providing a high quality permanent record of the retinal appearance, which can be used for monitoring of progression or response to treatment, and which can be reviewed by an ophthalmologist, digital images have the potential to be processed by automatic analysis systems. We have described the preliminary development of a tool to provide automatic analysis of digital images taken as part of routine monitoring of diabetic retinopathy in our clinic. Various statistical classifiers, a Bayesian, a Mahalanobis, and a KNN classifier were tested. The system was tested on 134 retinal images. The Mahalanobis classifier had the best results: microaneurysms, haemorrhages, exudates, and cotton wool spots were detected with a sensitivity of 69, 83, 99, and 80%, respectively.

Incidence of liver disease in people with HFE mutations.

BACKGROUND: Most patients with haemochromatosis have mutations of the HFE gene. However, the risk to people with HFE mutations of developing disease manifestations of haemochromatosis is not known. AIMS: To determine the risk of developing cirrhosis and liver cancer in individuals with HFE mutations in a population where few people were being treated for haemochromatosis. METHODS: 215 archive biopsy specimens of liver cancer (n=34) and cirrhosis (n=190) were retrieved from histology archives. Blood samples from 1000 individuals from the normal population were also collected. DNA was extracted from the biopsy specimens and exons 2 and 4 of the HFE gene were amplified using polymerase chain reaction. The products were analysed for the C282Y (845A) and H63D (187G) mutations. RESULTS: Three (8.8%) patients from the liver cancer group were homozygous for the C282Y mutation. Five (2.6%) patients from the cirrhosis group were homozygous for the C282Y mutation. One case fell in both the liver cancer and cirrhosis groups. C282Y homozygosity was thus significantly more frequent in both groups than in the normal population. These 215 cases are representative of a population of about 250 000 over 20 years. During this period we estimate that about 260 births or deaths of C282Y homozygous individuals occurred within this population. CONCLUSIONS: A diagnosis of liver cancer or cirrhosis is rare in the lifetime of individuals from this population who are homozygous for the C282Y mutation (2.5%; upper 95% confidence interval (CI) = 8%). Similarly liver disease is rare among C282Y/H63D compound heterozygotes (1%; upper 95% CI = 3.5%).

Focused obstetrical clinic for active duty junior enlisted service women: model for improved outcomes.

OBJECTIVE: To evaluate the utility of an interdisciplinary clinic in improving perinatal outcomes for all pregnant patients of junior enlisted rank (E4 and below) in response to previous reports that this group is at higher risk for adverse outcomes. METHODS: The study population included all junior enlisted active duty patients (E4 and below) delivering between January 1, 1993, and June 30, 1996. Outcomes for patients receiving care in a focused active duty obstetrical clinic were compared with outcomes in similar cohorts of senior active duty patients (E5 and above) and non-active duty pregnant patients. Evaluation was based on perinatal outcomes, including chorioamnionitis, postpartum hemorrhage, intrauterine growth retardation, cesarean delivery, preterm delivery rates (< 37 weeks), postterm delivery rates (> 41 weeks), postpartum days, mean gestational age at delivery, mean delivery weights, Apgar scores at 1 and 5 minutes, preeclampsia, and premature labor. Variables with potential to confound perinatal outcomes were also studied. Confounding variables included tobacco use, gestational diabetes, chronic hypertension, thyroid disease, history of substance abuse, and alcohol use. Power analysis accomplished before initiation of the study showed adequate sample size (> 240 patients in each group) to demonstrate statistically different rates of preterm delivery. Statistical analysis was done using the chi 2 test for categorical variables and Student's t test for continuous variables. RESULTS: There were no statistical differences between junior active duty patients, senior active duty patients, and non-active duty patients in preterm delivery and other outcome variables. CONCLUSION: The focused obstetrical clinic, conducted for junior enlisted soldiers by a senior nurse practitioner, appears to provide an intervention that ensures perinatal outcomes equal to those of both the non-active duty and the senior active duty population.

Hospital readmission after cardiac surgery. Does "fast track" cardiac surgery result in cost saving or cost shifting?

BACKGROUND: Intense medical and economic pressures have created "fast track" cardiac surgery in which clinical services are streamlined and early discharge is encouraged. Does this strategy promote significant cost saving or merely cost shifting? In a global system of reimbursement, the economic benefit of decreasing patient length of stay may be offset by high rates of patient readmission. This study was undertaken to determine the 30-day readmission rate after cardiac surgery and to analyze trends of readmission diagnoses. METHODS AND RESULTS: From October 1, 1996 to July 31, 1997, 460 consecutive cardiac surgical operations were performed at 1 institution. There were 25 deaths and 8 patients who remained as inpatients at the 30-day postoperative deadline for readmission. Two patients had 2 operations. Therefore, 527 operations were performed on 525 patients. There were 110 readmissions after 527 operations for a readmission rate of 20.9%. A significant number of readmissions (49%) were to outside hospitals. Readmission diagnoses were: atrial fibrillation (23%); angina, congestive heart failure, or ventricular tachycardia (20%); leg wound (15%); sternal wound (5%); pneumonia (5%); gastrointestinal complaints (5%); neurologic event (2%); and miscellaneous (25%). Patients discharged > or = 7 days postoperatively were twice as likely to be readmitted as those discharged on postoperative days 4, 5, or 6. CONCLUSIONS: Readmission after cardiac surgery is common and frequently (49%) to outside institutions. Patients discharged > or = 7 days postoperatively represent the patients at greatest risk of readmission and, therefore, warrant closer scrutiny before discharge.

Beyond retinal screening: digital imaging in the assessment and follow-up of patients with diabetic retinopathy.

Many screening methods are available for detecting diabetic retinopathy. However, once patients develop retinopathy, it is unclear as to what method should be used for their review. We describe a novel and integrated system for the screening and treatment of diabetic retinopathy using high street optometrists for primary screening and digital imaging as a secondary screening tool, with referral to a joint retinal clinic only where ophthalmological intervention may be required. Of 3586 patients screened by optometrists, 328 were classified as having moderate/severe pre-proliferative retinopathy or diabetic maculopathy. Patients with proliferative retinopathy (1% of the total) were recalled directly to the joint retinal clinic. A consecutive sample (281) of these patients, together with a further 100 classified by the optometrists as having no or background retinopathy were compared using digital images and standard 35 mm colour transparencies. These, together with the original optometrist reports, were reviewed independently and individually by an ophthalmologist. A further sample of 124 patients who had undergone both digital imaging and ophthalmologist slit-lamp examination were also compared. Comparison of 35 mm colour transparencies with optometrist reports showed the latter had a sensitivity for detecting sight-threatening retinopathy (STR) of 62%, a specificity of 84%, and a kappa score of 0.62. The results for digital images were 90%, 97%, and 0.90, respectively, although the extent of retinopathy was under-reported in 10 patients. With ophthalmologist slit-lamp examination as the gold standard, the sensitivity of digital imaging was 90% with a substantial level of agreement between them (kappa 0.61). We conclude that digital images provide an efficient method for the follow-up of patients with established or previously treated retinopathy.

c-myc locus amplification and the acquisition of trisomy 8 in the evolution of chronic myeloid leukaemia.

The biological progression of chronic myeloid leukaemia is often associated with secondary cytogenetic abnormalities but the molecular mechanisms underlying this progression are poorly understood. This study explores the association of c-myc gene amplification with the progression of chronic myeloid leukaemia in fourteen individuals. Three of these cases showed amplification of c-myc during the course of their disease. Cytogenetic and molecular analysis of serial samples from some patients suggested the successive expansion of distinct clones of malignant cells. Our findings also suggest that trisomy 8 and locus amplification could represent alternative mechanisms for increasing c-myc gene dosage.

Consistent fusion of ZNF198 to the fibroblast growth factor receptor-1 in the t(8;13)(p11;q12) myeloproliferative syndrome.

The 8p11 myeloproliferative syndrome is a rare, aggressive condition associated with reciprocal translocations of chromosome band 8p11, most commonly the t(8;13)(p11;q12). To identify the genes involved in this translocation, we used fluorescence in situ hybridization (FISH) analysis to show that the chromosome 8 breakpoints fell within YAC 899e2 and that the chromosome 13 breakpoints are clustered in a region flanked by YACs 929f11 and 911h8. FISH using chromosome 13 PAC clones indicated that the t(8;13) is not simply a reciprocal translocation but also involves an inversion of 13q11-12. Exon trapping of a PAC that spanned the chromosome 13 translocation breakpoints led to the identification of a gene, ZNF198, that detected rearranged bands when used as a probe against Southern blots of patient DNA. Conceptual translation of the full-length ZNF198 cDNA sequence predicts a protein of 1377 amino acids that shows significant homology to the DXS6673E/KIAA0385 and KIAA0425 proteins. Alignment of these three proteins revealed a novel, conserved Zn-finger-related motif (MYM domain) of the general form CX2C19-22CX3CX13-19CX2CX19-25FCX3CX3F/Y that is repeated five times in each protein. To identify the translocation partner gene on chromosome 8, 5' and 3' RACE polymerase chain reactions (PCRs) were performed on patient RNA with several combinations of ZNF198 primers. Clones were identified in which the ZNF198 was fused to exon 9 of the fibroblast growth factor receptor-1 (FGFR1), a gene known to map to 8p11. An identical ZNF198-FGFR1 fusion was detected in the three patients with a t(8;13) for whom RNA was available; reciprocal FGFR1-ZNF198 transcripts were not detected. Rearrangements of both ZNF198 and FGFR1 were found in two further patients by Southern blotting. ZNF198-FGFR1 includes the five MYM domains of ZNF198 and the intracellular tyrosine kinase domain of FGFR1. We hypothesize that this fusion leads to constitutive activation of the FGFR1 tyrosine kinase in a manner analogous to the activation of ABL by BCR in chronic myeloid leukemia.

A differential PCR assay for the detection of c-erbB 2 amplification used in a prospective study of breast cancer.

AIMS: To establish a robust differential polymerase chain reaction (PCR) assay for the detection of c-erbB 2 amplification in breast cancer that can be used in a routine pathology laboratory. Once established, the assay was used in a prospective study of breast tumours to investigate the relation between c-erbB 2 amplification and both recognised prognostic features and short term clinical outcome. METHODS: The differential PCR was used for the co-amplification of c-erbB 2 and a reference gene from 48 tumour DNA samples and control DNA samples. The ratio of the two genes was determined by image analysis of the PCR products electrophoresed on a highly resolving agarose gel. RESULTS: The differential PCR assay was shown to be accurate and reproducible using the conditions outlined. Twenty six per cent of the breast cancer patients were shown to have c-erbB 2 amplification in their tumour biopsies. Twenty eight per cent of the patients died of their disease or had disease recurrence during the follow up period and 73% of these patients had amplification of c-erbB 2. CONCLUSIONS: A significant association was found between c-erbB 2 amplification and early disease recurrence. This assay could be used to provide a marker for poor prognosis in breast cancer.

Cyclin D1 amplification and expression in human breast carcinoma: correlation with histological prognostic markers and oestrogen receptor expression.

Aims-To study the amplification of the Cyclin D1 gene (CCND1) in human breast carcinoma; to relate this to Cyclin D1 protein expression; to relate these parameters to recognised pathological prognostic factors, including oestrogen receptor (ER) status.Methods-DNA extracted from frozen sections of breast tumours (n = 36) was used for Southern blotting. Probes for CCND1, c-myc and the immunoglobulin heavy chain locus (IgH) were hybridised to tumour DNA. Immunocytochemical expression of Cyclin D1 protein and ER was studied in paraffin wax sections from the same tumours.Results-Amplification of CCND1 was observed in 11% (four of 36) of tumours studied. Over expression of Cyclin D1 protein was observed in 73% (30/41) of tumours. There was no correlation between recognised histological prognostic markers and either gene amplification or expression. However, a weak association was seen between Cyclin D1 expression and ER status.Conclusions-A disparity exists between locus amplification and over expression of Cyclin D1, suggesting the existence of another mechanism for raised protein expression. No significant correlation was detected between either Cyclin D1 amplification or over expression and established prognostic markers.

t(8;13) (p11;q12) translocation in a myeloproliferative disorder associated with a T-cell non-Hodgkin lymphoma.

An unusual cytogenetic translocation, t(8;13) (p11;q12), is described in a patient presenting with a CML-like myeloproliferative disorder associated with a high-grade T-cell lymphoma. Evidence is presented suggesting that the breakpoint region in the translocation involves a site implicated in both the T cell malignancy and the abnormal granulocyte proliferation.