Endoscopic Retrograde Cholangiopancreatography Under General Anesthesia Compared to Conscious Sedation Study

Background

Endoscopic retrograde cholangiopancreatography (ERCP) is used to diagnose and treat pancreatic and biliary disease. The current standard is to conduct ERCP under conscious sedation (CS). Patient movement and agitation during ERCP under CS can result in procedure failure and complications. Aiming to reduce procedure failure rates and complications, Kelowna General Hospital (KGH) in British Columbia, Canada transitioned to performing ERCP under general anesthesia (GA) as the practice standard.

Objective

To determine if conducting ERCP under GA compared to CS decreases procedure complications, particularly post-ERCP pancreatitis (PEP).

Methods

The charts of 2,198 patients who underwent ERCP at KGH between 2015 and 2020 were reviewed. Before September 17, 2017, ERCP was performed under CS (n = 1,316). Afterwards, ERCP was conducted under GA (n = 882). Demographic, clinical, and procedural data were extracted. The data were analyzed using univariate and multivariate statistical analysis.

Results

Procedure failure rates (CS = 9 percent, GA = 3 percent, P < 0.001) decreased in the GA cohort after adjusting for age, sex, and co-morbidities. Thirty-day mortality, intensive care unit (ICU) transfer, returns post-discharge, PEP, and cholangitis rates were similar between cohorts.

Conclusion

Performing ERCP under GA compared to CS resulted in an increase in procedural success rates. Other complication rates were similar between groups.

Tuberculin skin testing and QuantiFERON™-TB Gold Plus positivity among household contacts in Vietnam

SETTING

TB infection (TBI) is diagnosed using the technique-dependent tuberculin skin test (TST) or costly, more accurate interferon-gamma release assays. The TST (⩾10 mm) threshold was indicated by previous research among household contacts in Vietnam, but routine implementation with a different tuberculin reagent showed unexpectedly low TST positivity.

OBJECTIVE

TST (⩾5 mm and ⩾10 mm) results were compared to QuantiFERON™-TB Gold Plus (QFT) results in household contacts during community campaigns in 2020 and 2021.

DESIGN

This was a cross-sectional multi-center implementation study.

RESULTS

Among 1,330 household contacts in 2020, we found a TBI prevalence of 38.6% (QFT), similar to TST ⩾5 mm (37.4%) and higher than TST ⩾10 mm (13.1%). QFT+/TST+ was higher for TST ⩾5 mm (20.7%) than TST ⩾10 mm (9.4%). QFT was not discordant with TST ⩾5 mm (McNemar's test = 0.6, P = 0.5) but was discordant with TST ⩾10 mm (McNemar's test = 263.9, P < 0.01). Older age and Southern region increased odds for positive TST ⩾5 mm and QFT with weaker associations for TST ⩾10 mm. Agreement and discordance were similar in 2021 for 1,158 household contacts.

CONCLUSION

Tuberculin reagents affect TST positivity rates. High TB burden countries should monitor reliability of TBI diagnosis, including tuberculin potency, cold chain, and TST technique to optimize eligibility for TB preventive treatment.

A95 OUTCOMES OF ERCP UNDER CONSCIOUS SEDATION COMPARED TO GENERAL ANESTHESIA: A PRE-POST RETROSPECTIVE COHORT REVIEW

Background

Endoscopic retrograde cholangiopancreatography (ERCP) is a diagnostic and therapeutic procedure used to address pathologies of the pancreatic and biliary systems. ERCP performed under conscious sedation (CS) is the current standard of care but is limited by patient movement and agitation, especially in the context of lengthy or technically complex cases. Recent literature suggests that general anesthesia (GA) may optimize patient comfort and safety while reducing complications such as pancreatitis, perforation, and mortality. In October 2017, Kelowna General Hospital (KGH) transitioned the standard anesthesia modality for ERCP from CS to GA.

Aims

To investigate differences in complications and patient outcomes for ERCP performed under CS (n=1334) before the practice change compared to GA (n=899) after the practice change.

Methods

Our study is a pre-post retrospective chart review of 2,233 patients who underwent ERCP between 2015 and 2020 at KGH. Demographic, clinical, procedural and outcome data were extracted from patient charts, and the data in CS and GA groups were compared using univariate statistical analysis.

Results

Preliminary results show rates of post-ERCP pancreatitis (6% vs. 4%; p=0.018) and rates of procedure failure (8% vs. 3%; p&lt;0.001) were statistically significant and higher under CS before the practice change compared to under GA afterwards, respectively. The 30-day mortality rates, ICU transfer rates, return rates post-discharge, and rates of cholangitis were similar.

Our study showed improvements in several patient safety outcomes, including lower procedure failure rates and lower post-ERCP pancreatitis rates with ERCP performed under GA compared to CS.

Conclusions

Performing ERCP under GA rather than under CS is a valuable practice change that should be considered by ERCP-related programs across all health authorities due to its potential to optimize both patient comfort and safety significantly. The reduction in complication rates may have implications for net cost savings in the long term.

Funding Agencies

Kelowna General Hospital Foundation, Interior Health

Differential protein phosphorylation is responsible for hypoxia-induced regulation of the Akt/mTOR pathway in naked mole rats

Naked mole rats (NMRs, Heterocephalus glaber) are among the most hypoxia-tolerant mammals known. They can reduce their metabolic rate (>85%) under severe hypoxia, remain moderately active and recover with no obvious signs of damage. Hence, NMRs are an excellent model for studying mammalian hypoxia tolerance. The current study characterized the involvement of posttranslational modifications in regulating the Akt/mTOR pathway that regulates protein synthesis, and the responses of key ribosomal proteins in order to assess tissue-specific responses to 4 h exposure to 7% O₂ (compared to controls at 21% O₂). Results showed a tissue-specific regulation of the Akt/mTOR pathway via differential phosphorylation. Relative amounts of p-TSC(S939) in brain and of p-TSC(S939), p-Akt(473) and p-PTEN(S380) in liver increased under hypoxia, whereas levels of IGF1R(Y1135/1136) in liver decreased. In skeletal muscle, levels of p-Akt(S473) and p-PTEN(S380) decreased during hypoxia, whereas lungs showed an increase in p-mTOR(S2884) content but a decrease in p-RPS6(S235-236) under the same conditions. Analysis of the phosphorylation states of ribosomal proteins revealed increases in p-4E-BP1(T37/46) content in brain and lungs under hypoxia, as well as a rise in total 4E-BP1 protein level in liver. Phosphorylated eIF-4B(S422) content also increased in liver while levels of p-eIF-2α(S51), and eIF-4E(S209) decreased during hypoxia in liver. Overall, hypoxia altered the Akt/mTOR pathway, which correlated with a general decrease in activity of the ribosomal protein biosynthesis machinery in muscle, lung, and brain of NMRs. However, the increase in eIF-4B in liver suggests the potential promotion of cap-independent mRNA translation mechanism operating under hypoxic stress.

Naked mole rats activate neuroprotective proteins during hypoxia

Naked mole rats are a long-lived animal model that age much like humans, but that can also withstand oxidative damage, cancer, neurodegenerative diseases, and severe hypoxic conditions, which is of particular interest to this study. The conditions of their underground burrows result in competition for oxygen consumption, yet despite this oxygen deprivation they emerge unscathed. To understand the mechanisms in place to facilitate neuronal preservation during hypoxia, we investigated the protein levels of well-known cell-stress factors. We found that under hypoxic conditions, nearly half of the proteins measured increased expression in brain, while only a few decreased. Under hypoxic conditions there appeared to be a HIF1α-centered response, where HIF1α and its interactors carbonic anhydrase 9, CITED2, p21/CIP1, and NFκB1, among others, were upregulated. Concurrently, a hypoxia-induced decrease of cytochrome c was consistent with decreased mitochondrial function and protection from apoptosis. The picture that emerges is one of neuroprotection, cell-cycle arrest, and the promotion of antiapoptotic functions, all of which are consistent with conserving energy and maintaining neural integrity under low oxygen levels. These results suggest how this species may be poised to face hypoxia and contribute to its remarkable ability to deal with myriad of other damaging factors and sets the stage for future work on the neuroprotective facilitators we identified.

Species composition and level of infestation of cockroaches in three areas in Hanoi

A study on the species composition and the level of infestation of cockroaches was carried out from April 2013 to October 2014 in three localities of Hanoi, Vietnam, namely the Lan Ong-Old Town, Linh Dam condominium and Tan Da Resort. Out of the 187 units of premises examined, 44.9% of units were infested with cockroaches. A total of 576 cockroaches were trapped, of which six species were identified: Periplaneta americana (L.) was the most dominant species (72.1%), followed by Blattella germanica (L.) (14.8%), Pycnoscelus surinamensis (L.) (7.3%), Periplaneta australasiae (Fabricius) (2.9%), Periplaneta fuliginosa (Serville) (1.9%) and Supella longipalpa (Fabricius) (1.0%). Infestation was the highest in Lan Ong (74.0%), followed by Linh Dam (40.5%) and Tan Da (25.9%). Cockroaches were abundantly found in warehouses (100%), electrical distribution room (56.3%), and kitchens (46.7%).

Evolution and adaptation of H5N1 influenza virus in avian and human hosts in Indonesia and Vietnam

Highly pathogenic avian influenza virus H5N1 is endemic in poultry in East and Southeast Asia with disease outbreaks recently spreading to parts of central Asia, Europe and Africa. Continued interspecies transmission to humans has been reported in Vietnam, Thailand, Cambodia, Indonesia and China, causing pandemic concern. Here, we genetically characterize 82 H5N1 viruses isolated from poultry throughout Indonesia and Vietnam and 11 human isolates from southern Vietnam together with sequence data available in public databases to address questions relevant to virus introduction, endemicity and evolution. Phylogenetic analysis shows that all viruses from Indonesia form a distinct sublineage of H5N1 genotype Z viruses suggesting this outbreak likely originated from a single introduction that spread throughout the country during the past two years. Continued virus activities in Indonesia were attributed to transmission via poultry movement within the country rather than through repeated introductions by bird migration. Within Indonesia and Vietnam, H5N1 viruses have evolved over time into geographically distinct groups within each country. Molecular analysis of the H5N1 genotype Z genome shows that only the M2 and PB1-F2 genes were under positive selection, suggesting that these genes might be involved in adaptation of this virus to new hosts following interspecies transmission. At the amino acid level 12 residues were under positive selection in those genotype Z viruses, in the HA and PB1-F2 proteins. Some of these residues were more frequently observed in human isolates than in avian isolates and are related to viral antigenicity and receptor binding. Our study provides insight into the ongoing evolution of H5N1 influenza viruses that are transmitting in diverse avian species and at the interface between avian and human hosts.

Dietary patterns and risk factors of diabetes mellitus among urban indigenous women in Fiji

The dietary patterns of indigenous Fijians are changing rapidly. Dietary relationships in regard to the prevalence of diabetes are poorly studied in Fiji. A survey was conducted to show the relationship of dietary patterns and other lifestyle factors for the development of diabetes among urban indigenous women in Fiji. A sample of 200 Fijian women aged 30-39 who agreed to participate were interviewed by the use of semiquantitative food frequency, 3 day-24 h recall study. Physical activity and ceremonial dietary customs were also taken into consideration. Anthropometry included measurements of height, weight, waist and hip. Total percentage bodyfat measurements and glycosuria tests were also conducted. The results showed high rates of obesity manifested in high percentage bodyfat, high body mass index (BMI) and high waist and hip ratio (WHR). The mean 24 h dietary intake exhibited a moderate intake of protein, high intake of fat and a low intake of carbohydrate. The carbohydrate reduction was a result from the decline in consumption of traditional staples. Consumption of cereals and related products favored the high intake of butter and margarine and also encouraged the use of cooking oil in frying varieties of flour products. The daily intake of anti-oxidant vitamins of beta-carotene and vitamin E were low, however there was a high intake of vitamin C. The food frequency study revealed cassava, bread and sugar were consumed daily as the main carbohydrate foods. Fish and meat were the most frequently consumed protein foods. The main beverage was sweet tea with whole-cream milk. Butter, margarine, coconut cream, cheap lamb flaps and cooking oil provided the main sources of fat. Levels of physical activity included high sedentary lifestyles with a high rate of subjects being overweight and obese. Ceremonial dietary customs showed a high consumption of meat and fish. Fruits were rarely consumed. Glycosuria existed among the age group under study. The impact of dietary transition, coupled with dietary excesses and physical inactivity, seem to be potential risk factors of diabetes among the indigenous women in the urban area.

Blood pressure, serum cholesterol concentration and their related factors in urban and rural elderly of Ho Chi Minh City

In Vietnam, information about blood pressure, serum lipids and their factors is limited. To obtain some of this information, a cross sectional nutrition survey was carried out in an urban and rural area of Ho Chi Minh City with 217 participants aged 60-69 y (148 females and 69 males). Anthropometry and blood pressure were measured. For three consecutive weekdays, 24 h dietary recalls were performed. Single 24 h urine was collected for sodium and potassium analysis. A fasting blood sample was taken and biochemical parameters were measured. Results indicate a high percentage of hypertension in urban (female: 35.5%, male: 43.8%) and rural areas (female: 22.2%, male: 35.1%). Blood pressure was correlated with body mass index (BMI) and 24 h urinary sodium-to-potassium (Na/K) ratio. A high prevalence of serum total cholesterol (TC) above 220 mg/dL (female: 55.3%, male: 31.3%) and overweight (female: 34.2%, male: 25.0%) were observed in urban residents. By contrast, 5.6% and 24.3% of rural females and males respectively had TC below 150 mg/dL and both genders had the same prevalence of underweight (32.4%). TC was positively correlated with body weight, BMI, dietary protein and dietary lipids. Overweight might be a major risk factor for hypertension in our urban elderly. A high Na/K intake ratio might be a risk factor for hypertension in both areas. The high prevalence of elevated TC in the urban area might to be related to the high lipid intake, and the high prevalence of low TC in the rural area might to be related to the low lipid intake.

Effects of Maillard reaction products on the oxidative cleavage and polymerization of protein under ascorbic acid-transition metal system

This study investigated the effects of Maillard reaction products (MRPs) on the oxidative cleavage and polymerization of BSA (bovine serum albumin) in an aqueous system. In L-ascorbic acid (AsA) and Cu(II) or Fe(III) reaction system, 50-60% of BSA was cleaved under physiological conditions (37 degrees C, pH 7.2). The oxidative cleavage induced by AsA-Cu(II) system was suppressed to the extent of 32-86% by model melanoidins or brown pigments from amino acids and foodstuffs. In the AsA-Fe(III) system, the oxidative cleavage was inhibited to the extent of 45-93% by melanoidins and brown pigments. However, this cleavage was promoted by amino acid Amadori rearrangement products and brown pigment from soy paste. Therefore, MRPs show both suppression and promotion activity on oxidative cleavage of BSA in the system of AsA and a transition metal. The quantity of Amadori rearrangement moiety (ARM) in melanoidins from Lysine and brown pigments molecules from foods was also measured. From these data, it was estimated that the suppression and/or promotion of oxidative cleavage of BSA did not only depend on the quantity of ARM, but also depended on the chemical structure of ARM in melanoidins or brown pigments.

The importance of quality control of sputum smear microscopy: the effect of reading errors on treatment decisions and outcomes

SETTING

Ho Chi Minh City, Vietnam.

OBJECTIVE

To evaluate the impact of slide reading errors at peripheral level on case-finding and treatment decisions.

DESIGN

Over a 6-month period in 1997, information on date, type of slide, results of other slides from the patient, and treatment status was collected for all slides from district TB centers detected as having reading errors during smear microscopy quality control re-readings.

RESULTS

Reading errors were detected in 117 slides: 115 (98.3%) were incorrectly read as negative, and 75 (65.2%) of these errors occurred in case-finding slides. In the 75 falsely negative case-finding slides, re-reading resulted in initiation of treatment in 38 patients (50.7%). The remaining 37 (49.3%) had only one positive slide and were told to return for follow-up after 6 months; the two (5.4%) who did return were both diagnosed with active TB. Detection of errors in the 40 false-negative follow-up slides resulted in treatment changes in four patients (10%).

CONCLUSIONS

Quality control plays a critical role in helping to ensure the timely diagnosis and treatment of new TB cases and appropriate management of patients currently on treatment. The usefulness of quality control could be enhanced by focusing greater efforts on case-finding slides initially read as negative.

Quality control of smear microscopy for acid-fast bacilli: the case for blinded re-reading

SETTING

Quality control of sputum smear microscopy, which is essential for ensuring correct tuberculosis (TB) diagnosis, is often performed through the unblinded rereading of all positive slides and a sample of negative slides.

OBJECTIVE

To assess misclassification error introduced by knowledge of prior results.

METHODS

The Southern Vietnam Regional TB Laboratory prepared three gold-standard sets of 750 slides: an unblinded set, an unblinded set in which 13% of negative slides were replaced by weakly positive slides purposefully mislabelled as negative, and a blinded set. Six provincial technicians who normally perform district quality control each reread 125 slides from each set.

RESULTS

In the three sets only one negative slide was misread as positive. In the unblinded set (referent), 2.9% (9/311) positive slides were misread as negative, compared with 18.7% (57/305) in the blinded set (prevalence ratio [PR] = 6.5; 95% confidence interval [CI] 3.3-12.8; P < 0.001), and 11.3% (33/293) in the unblinded set with mislabelled slides (PR = 3.9; 95%CI 1.9-8.0; P < 0.001).

CONCLUSIONS

False-negative error was more common than false-positive error. Knowledge of prior reading influences re-reading. Blinded re-reading of systematically selected slides would appear preferable, although this method requires high levels of proficiency among quality control technicians.

Chromosomal mapping and expression of the human cyr61 gene in tumour cells from the nervous system

AIMS

To characterise the human cyr61 gene (cyr61H) and determine its chromosomal locality. To compare expression of cyr61H in human tumour cell lines with that of two other structurally related genes, novH (nephroblastoma overexpressed gene) and CTGF (connective tissue growth factor), that are likely to play a role in the control of cell proliferation and differentiation.

METHODS

To isolate the human cyr61 gene, placental genomic and HeLa cDNA libraries were screened with murine cyr61 cDNA. The nucleotide sequence of the complete cyr61H cDNA was established. Both Southern blotting of a panel of somatic cell hybrids and in situ hybridisation on chromosomes were performed to map the cyr61H gene. Expression of cyr61H, novH, CTGF, and novH was analysed by northern blotting in both human neuroblastomas and glioblastoma cell lines.

RESULTS

Genomic and cDNA clones encompassing the cyr61H gene were isolated and characterised. Comparison of mouse and human cyr61 sequences indicated that their genomic organisation is highly conserved. Alignment of coding sequences highlighted the conservation of cyr61 regions that might be critical for its biological function. The data showed that the cyr61H gene is assigned to chromosome 1p22.3 and that different levels of cyr61H, CTGF, and novH mRNA have been detected in several human tumour cell lines derived from the nervous system.

CONCLUSIONS

The human cyr61 gene belongs to an emerging family of genes including CTGF/fisp12 and nov. The murine cyr61 encodes an extracellular cysteine rich protein that exhibits chemotactic activity, promotes attachment and spreading of cells, and potentiates the mitogenic effect of growth factors. Assignment of the cyr61H gene to chromosome 1p22.3 will allow studies to determine whether human pathologies derived from the nervous system or from other tissues are associated with chromosomal abnormalities involving this region. Although the coding regions of cyr61H, CTGF, and novH are highly homologous, a growing body of evidence suggests that expression of these genes is regulated differentially, and that a balance between expression of these genes might represent a key element in determining the stage of differentiation and/or the malignant potential of tumour cells.

Effect of long-term alcohol administration on bone metabolism in rats

The purpose of this study was to investigate the effects of different degrees of alcohol ingestion on bone strength and mineral density. Three different groups of growing female rats were administered different doses of an alcohol-water solution for a period of 6 months. These three groups were divided into: 1) the control group, which was only given water; 2) the moderate group, which was given 5% ethanol solution for only 2 h per day; and 3) the excess group, which was given only 5% ethanol solution for 163 days. This ethanol consumption induced no detrimental effect on biochemical parameters including liver function. The moderate group showed significantly higher (p < 0.05) levels of proximal metaphysis as compared to the control group, while there was no difference between the excess group and the control group. Similarly, in comparison to the control group, the moderate group exhibited a significant increase (p < 0.001) in bone mechanical strength, while the excess group showed either the same or decreased bone stiffness. These results indicate that alcohol intake has both beneficial and hindering effects on the skeleton, depending on the concentration and frequency of ethanol intake.

Emergence and scattering of multiple neurofibromatosis (NF1)-related sequences during hominoid evolution suggest a process of pericentromeric interchromosomal transposition

Type 1 neurofibromatosis (NF1) gene encodes for a member of the GTPase activating protein family and is considered to be a tumor suppressor gene. Its very high rate of de novo mutation in humans led us to study a specific feature of this gene: the presence of numerous NF1-related sequences. According to our results, the human genome contains at least 11 NF1-related sequences, nine of which are scattered near centromeric sequences of seven different chromosomes. These NF1-related sequences, whose extent is quite varied according to loci, are unprocessed copies of the NF1 gene, and bear numerous mutations. A phylogenetic analysis of the six largest sequences indicates that they are all derived from a common ancestor, which would have appeared 22-33 million years ago, and was subsequently duplicated several times during hominoid evolution. The most recent duplication and interchromosomal transposition occurred in the last million years suggesting that the process could still be ongoing. Intriguing similarities between the evolution of alpha-satellite DNA and NF1-related sequences suggest the involvement of a common genetic mechanism for the generation and pericentric spreading of these NF1 partial copies.

Dual localization of the human gene encoding hnRNP I/PTB protein to chromosomes 19p13.3 and 14q23

A cDNA probe representative of the human hnRNP I/PTB gene was used to perform fluorescence in situ hybridization (FISH) on metaphases of human chromosomes. A new localization was found on band 19p13.3 in addition to the previously reported localization to band 14q23. Identical results were obtained when FISH analysis was repeated with probes covering different parts of the hnRNP I cDNA clone. This supported the notion that most, if not all, of the sequences of the different parts of this clone are present on both chromosomes. Moreover, Southern blot analysis of DNAs from interspecies somatic hybrids containing chromosomes 19 and 14 revealed that the whole hnRNP I cDNA probe generated very similar patterns in each hybrid DNA. These data suggest that two closely related copies of the hnRNP I gene exist in the human genome.

Desmutagenicity of soybean after heating

The mutagenicity and desmutagenicity of extracts of soybeans heated at 225 +/- 5 degrees C were investigated by the Ames test. The soybeans were refluxed in water, methanol, or diethylether for 2 h. The aqueous and methanol extracts (2-4 mg/plate) of the heated soybeans exhibited strong desmutagenic activity of 43-92% against heterocyclic amines (Trp-P-1. Glu-P-2, IQ, MeIQx. PhIP), while no mutagenicity was observed. The desmutagenicity of the heated soybean extracts remained even after denaturation by 0.1 N HCl in vitro and absorption by the rat small intestine. The desmutagenic mechanism for heated soybeans was evaluated, and it was verified that the soybean extract exhibited its desmutagenicity by blocking the mutagenicity of activated Trp-P-1, and not by inhibiting the S9 enzyme system.

Assignment of the NTRK4 (trkE) gene to chromosome 6p21

Reverse transcriptase-polymerase chain reactions using foetal brain RNA with reverse and forward primers of the first, second and third NTRK4 region allowed us to obtain three amplified NTRK4 fragments. The specificity of amplified fragments was checked by digestion with restriction endonucleases AvrII, HindIII and PspII for the first, second and third regions, respectively. Each restriction site was specific for each amplified fragment. The fragment of the NTRK4 first region was also sequenced and the sequence determined was identical to the human NTRK4 sequence. The three amplified fragments were cloned in pBS. For the Southern technique, plasmid pBS-NTRK4a (with an insert of 1052 bp) detected a human 9-kb HindIII sequence which was localised unambiguously on chromosome 6. For fluorescence in situ hybridisation, the three plasmids, pBS-NTRK4a, pBS-NTRK4b (insert 924 bp) and pBS-NTRK4c (insert 1114 bp) were pooled and used as a probe. This NTRK4 probe was localised on 6p21. Of 50 metaphases analysed, 49 contained twin spot signals on both sister chromatids.

MDM2 amplification in a primary alveolar rhabdomyosarcoma displaying a t(2;13)(q35;q14)

This report describes a case of rhabdomyosarcoma associated with a 2;13 translocation and multiple double minute chromosomes. The origin of the amplified DNA was identified using comparative genomic hybridization, which pinpointed a unique spot at 12q13-->q14. Band 12q13 has been shown to contain several genes that are occasionally amplified in other sarcomas. Fluorescene in situ hybridization to tumor metaphases with probes specific for this region indicated that the double minutes contained the MDM2 gene but not the CDK4 gene. MDM2 amplification was further quantified by Southern hybridization, which showed a mean value of 25 copies per haploid genome. This is the first example of MDM2 amplification in a rhabdomyosarcoma.

The MUC5AC gene: RFLP analysis with the Jer58 probe

We have recently obtained evidence that the locus corresponding to three groups of partial tracheobronchial cDNAs (A = Jer47, B = Jer57, C = Jer58) which mapped to chromosome 11p15 and was given the symbol MUC5 corresponds to two distinct genes which we have provisionally called MUC5B and MUC5AC. Here we describe the detection, using the Jer58 probe, which contains a 24-bp tandem repeat, of polymorphism in the MUC5AC gene with seven different restriction enzymes.

A Tsp509I variant in exon 13 of the neurofibromatosis type 1 (NF1) gene allows the identification of both alleles at the mRNA level

We describe here a new sequence variant occurring in the coding region of the neurofibromatosis (NF1) gene (exon 13). This exonic polymorphism can be directly investigated by simple restriction enzyme digestion of RT-PCR (reverse transcription-polymerase chain reaction) products, making it a powerful tool for examining allele-specific mRNA expression levels.

A new hybrid cell line containing only human chromosome 15 selected through fluorescence in situ hybridization and characterized by Alu-PCR amplification of the human DNA

Human Cot1 DNA directly labeled with dUTP-fluorochromes (FITC, Rhodamin) and used as a probe, allowed rapid detection of one or a few human chromosomes in human-hamster hybrid cells by in situ hybridization (FISH). A hybrid cell line containing only a human acrocentric chromosome was isolated (CH35B2D). The DNA from this hybrid was used for PCR amplification with a single Alu (A33) primer. After agarose gel electrophoresis, a continuum of intense bands of between 400-700 bp was observed with A33-PCR products. No amplified product was visible with hamster DNA. FISH on normal human metaphases of biotinylated Alu-PCR products obtained with Alu A33 and compétition with human Cot1 DNA showed decoration, with high specificity for chromosome 15. It was identified after R banding obtained with PI or DAPI in an antifade adjusted to pH11 with NaOH. Under the applied conditions, the Alu (A33) products are expected to be useful for characterization, by specific decoration of chromosome 15 aberrations in pathological cells. CH35B2D could be employed for functional studies of genes located on chromosome 15.

Human gp130 transducer chain gene (IL6ST) is localized to chromosome band 5q11 and possesses a pseudogene on chromosome band 17p11

Human gp130 (IL6ST) is one of the most widely used chains of the cytokine receptor family. Indeed, it is involved in signal transduction of interleukin-6, interleukin-11, leukemia inhibitory factor, oncostatin M, and ciliary neurotrophic factor. In a previous report, IL6ST was assigned to chromosomes 5 and 17. Here we specify the chromosomal sublocalization of IL6ST and show that the sequence detected on 17p11 corresponds, in fact, to a nontranscribed pseudogene, whereas the active gene is located at chromosome band 5q11.

Structural organization and chromosomal localization of a human gene (HIP/PAP) encoding a C-type lectin overexpressed in primary liver cancer

We previously identified, through differential screening of a human primary liver cancer library, a novel gene (named HIP) the expression of which is markedly increased in 25% of human primary liver cancers. HIP mRNA expression is tissue specific since it is restricted to pancreas and small intestine. HIP protein consists in a signal peptide linked to a carbohydrate-recognition domain (CRD), typical of C-type lectins without other binding domains. We have proposed that HIP and related proteins belong to a new family of C-type lectins. Drickamer [Drickamer, K. (1993) Curr. Opin. Struct. Biol. 3,393-400] included this group of proteins in his classification of C-type lectins as the free CRD (group VII) lectins. In the present report we describe the genomic organization and the chromosomal localization of HIP. We have shown that HIP is in fact the pancreatitis-associated protein (PAP) and provided a phylogenetic analysis of the free CRD lectins. Furthermore, the analysis of HIP/PAP gene indicates that the HIP/PAP CRD is encoded by four exons, a pattern shared with all members of this group of proteins. This common intron-exon organization indicates an ancient divergence of the free CRD-lectin group from other groups of C-type lectins. We provide evidence for the localization of HIP/PAP on chromosome 2, suggesting previous duplication of HIP/PAP and the related reg I alpha and reg I beta genes from the same ancestral gene. Finally, the sequence of the 5' upstream region of the HIP gene shows several potential regulatory elements which might account for the enhanced expression of the gene during pancreatic inflammation and liver carcinogenesis.

Assignment of the human 8.5 H gene to chromosome 5, region 5q35

The human 8.5 H probe was isolated from a human cerebellum cDNA library with a probe corresponding to the coding region of the murine 8.5 M cDNA. This cDNA isolated from a murine cDNA library constructed from newborn cerebral hemispheres was selected because of its strong expression in embryonic neurons. Consequently the corresponding human gene could be a candidate for hereditary neurodegenerative diseases. The human 8.5 H gene was assigned by somatic hybrid analysis to chromosome 5; this chromosome contains the gene(s) for spinal muscular atrophy (SMA), a group of heritable degenerative diseases that selectively affect the anterior horn motor neuron of the spinal cord. The localization by in situ hybridization of 8.5 H on 5q35 excluded the possibility that this gene is identical to SMA. The SMA gene(s) was (were) known, from linkage analysis, to be in a region (5q11.2-q13.3) very distant from 5q35.

Cloning of a breakpoint cluster region at band 3q27 involved in human non-Hodgkin's lymphoma

In a previous cytogenetic analysis, we showed the recurrence of translocations involving band 3q27 and immunoglobulin gene regions in 20 out of 319 patients with non-Hodgkin's lymphoma (NHL). We report here the molecular cloning of the translocation breakpoint from tumor cells of a patient (LAR) with t(3;14)(q27;q32) and the isolation of DNA probes which identify a major translocation cluster region (MTC) at band 3q27. A DNA library from LAR tumor cells was screened with a JH probe and several clones were identified corresponding either to a somatic rearrangement of JGH genes (V4-D2-J6-C mu clonal rearrangement) or to the t(3;14). Analysis of the t(3;14) breakpoint showed that chromosome 3 material was translocated to an inverted 14q32 VH-containing fragment which was itself translocated to the J3 gene. Chromosome 3-assigned probes were used to investigate local DNA rearrangements in a series of NHL with 3q27 translocations. Rearrangements were detected in 13 of 17 patients including 9 of 11 with t(3;14)(q27;q32), 1 of 2 with t(2;3)(p12;q27), 1 of 2 with t(3;22)(q27;q11), and 2 of 2 NHL with translocations not involving an IG gene, namely, t(3;4)(q27;p11) and t(3;7)(q27;p12). The finding of this MTC should be useful for diagnostic and prognostic studies and for the identification of a novel oncogene at band 3q27 involved in the development of B cell NHL.

Rearrangements between irradiated chromosomes in three-species radiation hybrid cell lines revealed by two-color in situ hybridization

A human-hamster hybrid cell line containing only the human X chromosome (GM06318B) was exposed to 6,000-7,000 rad of X-rays and fused with a mouse cell line (CL1D,TK-). Three radiation hybrids, LXKC40, LXKC50, and LXKC56, were selected among 39 independent clones containing human material. Two-color in situ hybridization with total genomic DNA probes (cot1 human DNA and hamster total genomic DNA) was used to analyse the irradiated chromosome rearrangements. With this three-species model system (human-hamster-mouse) and the chromosome painting process it was possible to determine the origin of each chromosomal fragment in metaphase and interphase. The results obtained indicate preferential rearrangement between irradiated human and hamster chromosomes. Whole, apparently intact hamster chromosomes were observed in all the mitoses. We suggest that these chromosomes could be neoformated from random fragments after irradiation. Hamster and human "minichromosomes" were also detected. While the integration of human material into the mouse genome was exceptional, the integration of hamster material into mouse chromosomes was more frequent. During interphase the irradiated chromosome domains were often at the periphery of the nucleus. Irradiated material protruded at the periphery of the nuclei. Micronuclei containing hamster material were detected in the vicinity of these protrusions.

Isolation of kidney complementary DNAs down-expressed in Wilms' tumor by a subtractive hybridization approach

We applied a subtractive hybridization approach to isolate genes differentially expressed between mature kidney and Wilms' tumor. We constructed a complementary DNA library from a total mature kidney complementary DNA subtracted by an excess of mRNA from a Wilms' tumor, WAGR4, with a germline deletion of 11p13 and a somatic loss of alleles at 11p15. Six clones presenting a differential pattern of expression, positive with mRNA from the mature kidney and negative with mRNA from the Wilms' tumor WAGR4, were characterized. Among these clones were two as yet unknown expressed sequences (D11S877E and D15S109E) and four sequences from known genes: renal dipeptidase (DPEP1), alpha B-crystallin (CRYA2), uromodulin (UMOD), and plasma glutathione peroxidase (GPX2). The different patterns of expression of these genes in 11 Wilms' tumors, whether or not they are hereditary, reflect the well-documented pathogenetic heterogeneity for Wilms' tumors. We propose that these clones could be helpful for an improved histological characterization of Wilms' tumors.

A human pseudoautosomal gene encodes the ANT3 ADP/ATP translocase and escapes X-inactivation

We report that the human ANT3 ADP/ATP translocase gene is a pseudoautosomal gene located proximal to the GM-CSF receptor alpha chain gene (CSF2RA). An ANT3-homologous locus, likely corresponding to a pseudogene, maps to chromosome 9. The ANT3 gene is transcribed from the centromere to the telomere and contains in its first intron a CpG island mapped 1300 kb from the telomere. This gene is transcribed from the Y chromosome and from the active and inactive X chromosomes. This gene thus escapes X-inactivation as predicted for genes belonging to the pseudoautosomal region.

Assignment of the human lipoprotein lipase (LPL) gene to chromosome band 8p22

The lipoprotein lipase gene (LPL) was mapped to chromosome band 8p22 by in situ hybridization to human chromosomes. This confirms the status of this assignment, which was still provisional.

Physical mapping of human loci homologous to the chicken nov proto-oncogene

The human locus (novH) corresponding to the nov protooncogene overexpressed in avian nephroblastoma has been identified and mapped on chromosome 8q24.1. Another locus sharing homology with novH and corresponding to the connective tissue growth factor (CTGF) gene has also been mapped on chromosome 6q23.1. The chromosomal assignment of nov and CTGF proximal to c-myc and c-myb respectively is of interest because chromosomal abnormalities involving these regions have been associated with different human tumors including Wilms'.

Preparation of a rat brain histidine decarboxylase (HDC) cDNA probe by PCR and assignment of the human HDC gene to chromosome 15

The formation of histamine from its precursor histidine is catalyzed by histidine decarboxylase (HDC), a pyridoxal phosphate (PLP)-dependent decarboxylase. The knowledge of sequence similarities between various rodent HDCs permitted us to prepare a rat brain HDC cDNA probe. After reverse transcription of rat brain polyA + mRNA, the HDC cDNA obtained was amplified by the polymerase chain reaction using two specific primers. The resulting 1019-bp DNA was cloned in the p-MAL vector. Its sequence corresponds to the published data on rat fetal liver HDC. This 1019-bp rat probe detected two BamHI sequences in man; these were assigned to chromosome 15 by somatic hybrid cell analysis. According to the well-known homology between human chromosome 15 and mouse chromosome 2, the result obtained is in agreement with the published localization of HDC on mouse chromosome 2. The mapping of the human HDC gene on chromosome 15 is an original contribution to the chromosomal assignment of related PLP-dependent decarboxylases.

Mucin 4 (MUC4) gene: regional assignment (3q29) and RFLP analysis

The use of a probe (JER64) containing a mucin 4 (MUC4) cDNA insert of 1.83 kb allowed to assign by in situ hybridization, the MUC4 gene to 3q29. This probe detected RFLPs with all restriction enzymes used (BamHI, HindIII, PstI, EcoRI, and TaqI). Particularly numerous alleles were observed with PstI, EcoRI and TaqI, in a small sample of unrelated DNAs (25 digested with PstI, 8 with EcoRI and 8 with TaqI). The PIC values were 0.69, 0.63 and 0.70 for PstI, EcoRI and TaqI respectively. The polymorphisms observed of variable number of tandem repeat (VNTR) type are in relation with the presence of tandemly repeated nucleotide sequences in MUC4 gene.

The human ASM (adult skeletal muscle) gene: expression and chromosomal assignment to 11p15

A rat adult skeletal muscle probe (Asm15) originated from a rhabdomyosarcoma was used to isolate the human homologous sequence from a placenta cDNA library. Among several positive clones the longest EcoRI-EcoRI insert (ASM1) obtained was 1875 bp long with 72% homology with rat Asm15 cDNA sequence. Important variations of ASM1 RNA level were observed in different adult skeletal muscles. Expression of a 29kD ASM1 protein was demonstrated in human adult skeletal muscle lysates using an antiserum (PB1579) raised against the C terminal region of the rat Asm15 protein. The human ASM gene was assigned by somatic cell analysis with human (ASM1) and rat (Asm15) probes to chromosome 11, and by in situ hybridization with the human probe to 11p15, a chromosome region involved in human embryonal rhabdomyosarcomas. Except for the presence of a HindII restriction site, the results obtained for the restriction map and the sequence of ASM1 cDNA (data not shown) exhibited extensive homology with the human H19 DNA sequence which have been mapped with a mouse probe also in 11p15. This suggests that ASM/Asm and H19 may represent the same sequence (in this hypothesis the presence of the supplementary HindII site in our ASM1 probe is explained by polymorphic variability). However it was reported that human and mouse H19 mRNA did not encode for a protein but acted as an RNA molecule whereas in our present study ASM protein was detected in human adult skeletal muscle. This could be explained by important regulation of ASM protein expression during development and cell differentiation. However we cannot exclude for the different species studied (mouse, rat, and man) the hypothesis that H19 and ASM/Asm mRNA may represent two distinct messengers from the same gene or even from duplicated genes.

Relative order determination of four Yp cosmids on metaphase and interphase chromosomes by two-color competitive in situ hybridization

Two-color competitive in situ hybridization was used to cytogenetically order four Yp cosmid probes, located in the pseudo-autosomal and TDF regions. The probes were hybridized by pairs to metaphase and interphase chromosomes. On metaphase chromosomes, determination of order between sequences separated by 3 Mb from each other was possible on a statistical basis, whereas the relative position of sequences 0.6 Mb apart could not be determined. On interphase chromosomes the complete order between sequences separated by 0.6-6 Mb was obtained rapidly by measuring the distances between two cosmid spots of every cosmid pair used in 28 to 60 nuclei. Results demonstrate the potential power of fluorescent in situ hybridization at interphase for high resolution cosmid mapping.

Structural features of the core proteins of human airway mucins ascertained by cDNA cloning

Tracheobronchial secretions are one of the most important elements of the mucociliary system that protects the respiratory mucosa. They contain bronchial mucus, which is composed of a group of macromolecules secreted by the goblet cells of the epithelium and the submucosal glands. Bronchial mucins are the most characteristic molecules of this mucus. They form a group of complex, polydispersed O-linked glycoproteins containing sugars, which make up 80% of their weight. The protein core of human airway mucin has been difficult to sequence by traditional technologies because of its high content of serine and threonine residues linked to numerous oligosaccharide chains. We therefore prepared a lambda gt11 cDNA library from one sample of human tracheobronchial mucosa and screened this library with a polyclonal antibody directed against the apopeptides of human bronchial mucins. We obtained 20 positive clones that were sequenced. These sequences were classified into three different types. The use of the nucleotide probes from these clones in Northern blot analysis showed that the RNA messages were extremely polydispersed. At the current time, four of these probes allow us to map human tracheobronchial mucins genes to at least three different chromosomes. These results suggest that the peptide moiety of the human airway mucin is very heterogeneous.

C-myb proto-oncogene: evidence for intermolecular recombination of coding sequences

We have characterized a novel chicken c-myb exon whose sequences are specifically expressed in thymic cells. In situ hybridization experiments indicate that this thymus-specific coding exon is localized on a small chromosome, distinct from the large acrocentric chromosome 3 on which we recently mapped the bulk of 15 exons, common to the c-myb mRNA species expressed in hematopoietic cells of both B and T lineages. These observations indicate that intermolecular recombination is required for the tissue-specific expression of the c-myb proto-oncogene. We also show that these thymus-specific sequences are conserved in human DNA and lie on chromosome 17q25, whereas the human c-myb locus is localized on chromosome 6q22-23. Sequencing data obtained from genomic DNA and PCR analyses performed with c-myb mRNA species expressed in chicken thymic cells strongly suggest that a repeated decameric sequence plays a key role in the recombination process.

Molecular cloning and chromosomal localization of a novel human tracheo-bronchial mucin cDNA containing tandemly repeated sequences of 48 base pairs

A lambda gt11 cDNA library constructed from human tracheo-bronchial mucosa was screened with a polyclonal antiserum raised to chemically deglycosylated pronase glycopeptides from human bronchial mucins. Out of 20 positives clones, one partial cDNA clone was isolated and allowed to map a novel human tracheo-bronchial mucin gene. It contains 48 nucleotide tandem repeats quite perfectly identical which encodes a protein containing about 50% of hydroxy amino-acids. This clone hybridized to polydisperse messages produced by human tracheo-bronchial and human colonic mucosae. The gene (proposed name MUC 4) from which cDNA is derived maps to chromosome 3.

Reliability of cancer mortality statistics in Ontario: a comparison of incident and death diagnoses, 1979-1983

We compared the underlying cause of cancer death listed on death certificates, to the registry diagnosis from the incident file in the Ontario Cancer Registry (OCR). For the 68,772 cancer deaths having both a registry diagnosis and a cancer cause of death, 79.3% agreed between the two sources at the third digit level of ICD-9; this rose to 85.8% when sites were aggregated into about 30-site groups (positive predictive value 85.8%, sensitivity 82.9%). The most common sites, accounting for greater than 80% of all cancer deaths, all had agreement rates above 80%. Sites of questionable reliability, comprising less than 10% of all cancer deaths, included liver and larynx, and most other ill-defined and unspecified sites. Recommendations to improve the quality of published cancer mortality statistics include combining colon and rectum, and the non-Hodgkin's lymphomas. Caution in the use and interpretation of statistics for cancers of the liver and larynx is suggested owing to poor reliability.

Assignment of human tracheobronchial mucin gene(s) to 11p15 and a tracheobronchial mucin-related sequence to chromosome 13

Extensive heterogeneity of tracheobronchial mucin RNAs has been described recently. Based on the results of total or partial cDNA sequencing, the mucin cDNAs obtained were classified into three groups. The first group contained 24 bp tandem repeat sequences, the second exhibited homology at their amino- and carboxyl-terminals, and the third group seems to consist of alternative hydrophilic-hydrophobic zones. JER58, JER47 and JER57 probes, representing the first, second, and third tracheobronchial mucin families respectively, were used for chromosome assignment. In human DNAs digested with BamHI, the JER58 probe detected a sequence of 21 kb, the JER47 probe detected a major sequence of 21 kb and a minor sequence of 4 kb, and the JER57 probe detected two sequences of 1.8 kb and 1.3 kb. By somatic hybrid cell analysis, the JER58. JER47, and JER57 major sequences were assigned to chromosome 11 and the JER47 minor sequence to chromosome 13. By in situ hybridization the JER58, JER47 and JER57 probes were assigned to 11p15. Under the experimental conditions used, no specific hybridization to the chromosome 13 region was observed with the JER47 probe. Our results indicate that tracheobronchial mucin gene(s) is/are localized on 11p15. The minor JER47 BamHI sequence localized on chromosome 13 probably corresponds to a tracheal-mucin related sequence. The intestinal mucin gene was also recently localized to the same 11p15 region. Intestinal and tracheobronchial mucins appear different according to their tissue distribution and their cDNA nucleotide sequences. Tracheal mucin probes (JER58, JER47, JER57) and intestinal probes may represent independent genes on 11p15 or else different mRNAs from the same primary transcript produced by differential splicing. Further studies using mucin genomic probes for 11p15 will be required for the elucidation of tracheal and intestinal mucin gene organisation in this region.

[The habit of black lacquering of teeth and dental caries]

The habit of applying black lacquer to teeth is widespread in Vietnam. Observations are reported on its effect on the incidence of dental caries and its usefulness in caries treatment.

Localization of the human oncogene SPI1 on chromosome 11, region p11.22

Spi1 is an oncogene specifically activated in acute murine erythroleukemias induced by the Friend spleen focus forming virus (SFFV). Three probes were used for the chromosomal assignment of the human SPI1 oncogene: cDb1 and RaB2 correspond respectively to murine Spi1 and human SPI1 cDNA probes; C45a6B probe is a murine genomic DNA sequence located in the Spi1 5' region and is known as a major SFFV integration site in murine erythroleukemia cells. Somatic hybrid cells enabled cDb1 and RaB2 to be assigned to chromosome 11. The murine C45a6B probe, which is not included in the Spi1 gene, detected a homologous sequence on human chromosome 11. RaB2 was assigned to 11p11.22 by in situ hybridization. Three human genes known between 11p11 and 11p13 (FSHB, CAT, ACP2) were on murine chromosome 2. Therefore, the localization of human SPI1 on 11p11.22 was consistent with the assignment of the Spi1 oncogene to murine chromosome 2.

Localization of the choline acetyltransferase (CHAT) gene to human chromosome 10

A cDNA clone encoding the complete sequence of porcine choline acetyltransferase (CHAT) isolated by S. Berrard et al. (1987, Proc. Natl. Acad. Sci. USA 84: 9280-9284) was hybridized to TaqI digests of a panel of 25 human-rodent somatic cell hybrids and to a complementary panel of 10 human-rodent hybrids in order to determine the chromosomal localization of human CHAT. To enhance the detection of the human signal, hybridization and washings were performed under low stringency conditions on membranes presaturated with sonicated DNA from parental rodent strains. All informative human fragments had the same distribution among the hybrids, mapping CHAT to a single human chromosome. CHAT was assigned to chromosome 10 because all other chromosomes were eliminated by exclusion based on the analysis of the signal segregation. This result indicates that mutation of the CHAT gene cannot be responsible for the primary defect in familial Alzheimer's disease.

Assignment of the complement serine protease genes C1r and C1s to chromosome 12 region 12p13

C1r and C1s are distinct, but structurally and functionally similar, serine protease zymogens responsible for the enzymatic activity of the first component of complement (C1). Recent comparisons indicate a significant degree of sequence similarity between C1r and C1s and support the hypothesis that they are related by gene duplication. Complementary DNA probes for human C1r and C1s do not cross-hybridize even at mild stringency conditions and are therefore gene-specific. Using a panel of 25 human-rodent cell hybrids, we have independently assigned the C1r and the C1s genes to chromosome 12. In situ hybridization analyses were consistent with these assignments, showing in addition that both C1r and C1s are located on the short arm of the chromosome in the region p13. These data suggest that the homologous C1r and C1s genes have remained closely linked after duplication of a common ancestor. The C1r and C1s loci also provide useful polymorphic DNA markers for the short arm of chromosome 12.

Localization of the active gene of aldolase on chromosome 16, and two aldolase A pseudogenes on chromosomes 3 and 10

Southern blot analysis of human genomic DNA hybridized with a coding region aldolase A cDNA probe (600 bases) revealed four restriction fragments with EcoRI restriction enzyme: 7.8 kb, 13 kb, 17 kb and greater than 30 kb. By human-hamster hybrid analysis (Southern technique) the principal fragments, 7.8 kb, 13 kb, greater than 30 kb, were localized to chromosomes 10, 16 and 3 respectively. The 17-kb fragment was very weak in intensity; it co-segregated with the greater than 30-kb fragment and is probably localized on chromosome 3 with the greater than 30-kb fragment. Analysis of a second aldolase A labelled probe protected against S1 nuclease digestion by RNAs from different hybrid cells, indicated the presence of aldolase A mRNAs in hybrid cells containing only chromosome 16. Under the stringency conditions used, the EcoRI sequences detected by the coding region aldolase A cDNA probe did not correspond to aldolase B or C. The 7.8-kb and greater than 30-kb EcoRI sequences, localized respectively on chromosomes 10 and 3, correspond to aldolase A pseudogenes; the 13-kb EcoRI sequence localized on chromosome 16 corresponds to the aldolase active gene. The fact that the aldolase A gene and pseudogenes are located on three different chromosomes supports the hypothesis that the pseudogenes originated from aldolase A mRNAs, copied into DNA and integrated in unrelated chromosomal loci.