Expression and prognostic implications of cell cycle regulatory molecules, p16, p21, p27, p14 and p53 in germinal centre and non-germinal centre B-like diffuse large B-cell lymphomas

AIMS

To evaluate the different expression patterns and the prognostic significance of cell cycle regulatory molecules in diffuse large B-cell lymphomas (DLBCLs) of germinal centre (GC) and non-GC phenotypes.

METHODS AND RESULTS

Tissue microarray slides composed of 126 extranodal and 88 nodal DLBCLs were immunostained for p16, p21, p27, p14 and p53. DLBCLs were classified into GC and non-GC phenotype according to the immunohistochemical expression of bcl-6, CD10, and MUM1. Aberrant expression of p53 was more frequent in the GC phenotype in nodal cases (P = 0.038), and the loss of p16, p21 and p14 expression was significantly more common in the non-GC phenotype (P = 0.004, P = 0.001, P < 0.001). Concurrent disruptions of the p16-Rb and p14-p53 pathways as represented by the immunoprofile of p16/p14/p53 (-/-/+) were associated with a poor prognosis in the GC phenotype [mean survival 31 months in the p16/p14/p53 (-/-/+) group versus 62 months in the other groups, P =0.0485].

CONCLUSIONS

The expression and prognostic implications of cell cycle regulatory molecules differ between GC and non-GC phenotypes in DLBCLs. The immunoprofile of p16/p14/p53 (-/-/+) within the GC phenotype of DLBCLs can be defined as a poor prognostic subgroup.

Comprehensive resource: Skeletal gene database

The Skeletal Gene Database (SGD) is an integrated resource that provides comprehensive information about bone-related genes, mRNA, and proteins expressed in human and mouse, with rich links to numerous other electronic tools. SGD contains expressed sequence tag (EST) data from all the skeletal-related cDNA libraries that are available to the public. It supplies the query/data access analytic tools for users to search and compare each gene expressed in skeletal tissue(s). The results derived from EST tissue expression profiling will allow users to get the data on the mRNA copy numbers of each gene expressed in each tissue and its normalized value. From the SGD, researchers can obtain information regarding the name, symbol, size, exon/intron number, chromosomal location, LocusLink, and related disease (if any is known) of each gene. This electronic compendium also furnishes information on the protein of the corresponding gene including the protein size (amino acid number and molecular weight). It provides swift and ready access to other useful databases including OMIM, UniGene and PUBMED. The data will be updated regularly in step with current and future research, thereby providing what we hope will serve as a highly useful source of information and a powerful analytic tool to the scientific community.

Mutation analysis of the PIG-A gene in Korean patients with paroxysmal nocturnal haemoglobinuria

AIM

Paroxysmal nocturnal haemoglobinuria (PNH) is caused by deficient biosynthesis of the glycosylphosphatidylinositol (GPI) anchor in haemopoietic stem cells. Mutation of the phosphatidylinositol glycan class A (PIG-A) gene, an X linked gene that participates in the first step of GPI anchor biosynthesis, is responsible for PNH. The characteristics of somatic mutation of the PIG-A gene in Korean patients with PNH were studied.

METHODS

Twenty four patients with PNH were selected. Ham tests and sucrose haemolysis tests were carried out on all patients. The expression of CD59 in erythrocytes and granulocytes was investigated in 14 and five patients, respectively, to confirm the diagnosis. Dideoxy fingerprinting (ddF) was used to screen mutations, and direct sequencing of DNA was performed to characterise the mutations.

RESULTS

Gene mutation was detected in 12 of the 24 patients. The other 12 patients were negative in ddF screening. Ten new mutations and two known mutations were detected. The mutations consisted of five deletions, six substitutions, and one insertion. These mutations resulted in six premature terminations, three abnormal splicings, one missense mutation in exon 2, and two nonsense mutations. Two patients with venous thrombosis showed mutations in exon 3 only. Substitution mutations were seen in six patients and frameshift mutations in the other six.

CONCLUSIONS

There were 10 new mutations among the 12 mutations in the Korean patients with PNH and the characteristics of the mutations varied, with no significant hot spots in sites or types.

Lymphoid preponderance and the absence of basophilia and splenomegaly are frequent in m-bcr-positive chronic myelogenous leukemia

Chronic myelogenous leukemia (CML) with a minor bcr-abl transcript is a rare entity. We describe a 66-year-old female who was diagnosed with CML in the chronic phase. Molecular analysis of her Philadelphia chromosome using the reverse transcriptase polymerase chain reaction and subsequent sequencing revealed a minor bcr-abl transcript. Monocytosis resembling chronic myelomonocytic leukemia was observed without splenomegaly and basophilia. Her clinical course was indolent and maintained the chronic phase of CML for nearly 3 years under hydroxyurea treatment. A review of the 23 cases of m-bcr CML including this case showed the presence of monocytosis and the absence of basophilia and splenomegaly in 55.0%, 55.0%, and 70.0% of patients, respectively. The absence of basophilia was a significant finding in patients without monocytosis ( P=0.01). Although the hematological features or clinical outcomes were variable in m-bcr CML cases, all three cases at the onset of the blastic phase showed lymphoid crisis, implying an increased lymphoid leukemogenicity of minor bcr-abl transcripts.

Patient file management with a database using a personal computer

With the development of the personal computer, an advanced and more efficient way of storing patients' records was created. A personal computer may be set up to store, retrieve, sort, recall, graph, combine, and evaluate all aspects of your patients' care. This article introduces the impressive array of the personal computer's patient charting capabilities and the most popular programs that are designed to perform this task.

Molecular analysis of Spinocerebellar ataxias in Koreans: frequencies and reference ranges of SCA1, SCA2, SCA3, SCA6, and SCA7

Spinocerebellar ataxias (SCAs) are a heterogeneous group of neurodegenerative disorders. CAG repeat expansions in the causative genes have been identified as the basic cause of several types of SCAs, and have been used for the diagnoses and classifications of patients with ataxia. In order to assess the frequency and CAG repeat size ranges of SCAs, and to establish an effective strategy for molecular diagnosis, we performed a molecular analysis of SCA1, SCA2, SCA3, SCA6, and SCA7 in 76 patients. These patients were as follows: 32 with dominant inheritance, 39 sporadic cases, and 5 with unknown family histories. The normal and affected CAG repeat size ranges were established at five SCA loci in Koreans, which was consistent with previous reports. The total prevalence of the five types of SCAs was 39.5% in the 76 patients with ataxia, regardless of their family history. It was 75.0% in the 32 families with a dominant inheritance. The most frequent type was SCA3 (15.8%), followed by SCA2 (14.5%). Both types combined formed 76.7% of the 30 patients with CAG expansions. SCA1, SCA6, and SCA7 were less frequent, affecting 3.9%, 2.6%, and 2.6% of the cases, respectively. This mutation spectrum is quite different from a previous report concerning Koreans, but is similar to the distributions that are seen in several ethnic populations worldwide. For a correct and effective diagnosis of SCAs, we suggest that a molecular diagnosis be undertaken, even in patients without a family history, as well as those with a family history. A stepwise approach is also recommended. Patients with ataxia should be tested for SCA2 and SCA3. Individuals testing negative should be tested for SCA1, SCA6, and SCA7.

Cloning and characterization of a type II integral transmembrane protein gene, Itm2c, that is highly expressed in the mouse brain

An Itm2C cDNA encoding a member of the mouse type II integral transmembrane protein (Itm2) was cloned from a mouse 13.5 days' post-coitum (dpc) embryonic head cDNA library. The nucleotide sequence and protein prediction analyses indicate that the membrane topology of the mouse Itm2c is a type II integral transmembrane protein with the N-terminus being intracellular and C-terminus, which is considered as either an extracellular or a luminal organelle domain. The predicted protein consists of 269 amino acids with a calculated Mr of 30,482 and a theoretical pI of 8.83. A putative N-glycosylation site was identified at amino acid 171, Asn. The single N-glycosylation site is conserved in the three members of the family in both mice and humans. The amino acid sequence of Itm2C is 41 and 49% identical to those of mouse Itm2A and Itm2B, respectively. A single approximately 2.1 kb transcript was detected with different levels in all of the tissues examined by Northern blot analysis. The Itm2c was highly expressed in both adult and postimplantation embryonic brains, although weak or moderate signals were also detected in other adult tissues. Among the tissues examined, RT-PCR analyses in various adult tissue shows that the Itm2c expression is highest in the adult brain. The results from this study suggest that the cloned Itm2c is a member of the Itm2 family that is specifically expressed in adult brains, unlike other members.

Induction of cytochrome P450-dependent monooxygenase in mouse liver and kidney by rutaecarpine, an alkaloid of the herbal drug Evodia rutaecarpa

Rutaecarpine is one of the main alkaloids of an herbal remedy, Evodia rutaecarpa, which has been used for the treatment of gastrointestinal disorder and headache. Effects of rutaecarpine on hepatic and renal cytochrome P450 (CYP)-dependent monooxygenase were studied in C57BL/6J mice. Treatment of mice with rutaecarpine by gastrogavage at 50 mg/kg/day for three days resulted in 57%, 41%, 6-, and 6-fold increases of hepatic microsomal benzo(a)pyrene hydroxylation, 7-ethoxycoumarin O-deethylation, 7-ethoxyresorufin O-deethylation, and 7-methoxyresorufin O-demethylation activities, respectively. However, the treatment had no effects on hepatic oxidation activities toward benzphetamine, N-nitrosodimethylamine, nifedipine, and erythromycin. In the kidney, rutaecarpine-treatment resulted in 2-fold and 42% increases of microsomal benzo(a)pyrene hydroxylation and 7-ethoxycoumarin O-deethylation activities, respectively. The treatment also increased renal 7-ethoxyresorufin O-deethylation activity to a detectable level. Immunoblot analysis of microsomal proteins showed that rutaecarpine-treatment increased the protein levels of CYP1A1 and CYP1A2 in the liver, whereas hepatic level of CYP3A-immunoreacted protein was not affected by rutaecarpine. These CYPs were not detectable in the immunoblot analyses of control and rutaecarpine-treated mouse kidney microsomes. These results indicated that rutaecarpine was a CYP1A inducer and showed potent inductive effects on both CYP1A1 and CYP1A2 in the liver.

Leber's hereditary optic neuropathy mutations in Korean patients with multiple sclerosis

Several different mitochondrial DNA (mtDNA) sites for mutations of Leber's hereditary optic neuropathy (LHON) have been reported to be present in patients with multiple sclerosis (MS). To further study this association of LHON and MS in the Korean population, we tested 20 MS patients for the presence of mtDNA mutations at nucleotide (nt) 11778 in all 20 patients, and at nt 14484, nt 3460 and nt 15257 in 15, 12 and 12 patients, respectively. However, none of the MS patients exhibited any pathogenic LHON mtDNA mutations. In conclusion, we found no evidence for any association between MS and the LHON mutation in the Korean population.

Scar revision via resurfacing

Numerous techniques exist to treat noticeable facial scars. Techniques range from surgical excision to resurfacing. In this review of dermabrasion and laser resurfacing, we address the clinical considerations, techniques, adjuncts, and peri-operative management of scar resurfacing. Dermabrasion offers the advantage of being a tried-and-true technique familiar to surgeons. Recent advances in laser technology have resulted in the increased use of pulsed-dye lasers (PDLs), erbium:yttrium-aluminum-garnet (YAG) lasers, and CO(2) lasers. PDLs are effective for hypertrophic scars and show lower rates of recurrence compared with erbium:YAG and CO2 lasers. In contrast, erbium:YAG and CO(2) lasers are well suited to treating atrophic and acne scars. Chemical peels play a minor role in scar resurfacing and function primarily as an adjunct. Scar resurfacing is an integral part of scar camouflage and is often used in conjunction with excision and irregularization techniques.

Isolation of neuronal precursors from differentiating P19 embryonal carcinoma cells by neuronal T alpha 1-promoter-driven GFP

The induction of pluripotent P19 embryonal carcinoma (EC) cells with retinoic acid results in their differentiation into cells that resemble neurons, glia, and fibroblasts. To isolate and enrich the developing neurons from heterogeneously differentiating P19 EC cells, we used a recently introduced protocol combining the expression of green fluorescent protein (GFP) driven by a tissue-specific promoter and fluorescence-activated cell sorting. Cells were transfected with the gene for GFP, which is under the control of the neuronal T alpha 1 tubulin promoter. After four days of retinoic acid treatment, GFP was specifically detected in cells undergoing neuronal differentiation. Sorting of fluorescent differentiating P19 EC transfectants yielded populations highly enriched in neuronal precursors and neurons. Immunoreactivity for nestin and neurofilament was observed in 80 and 25% of the sorted cell population, respectively. These results demonstrate that differentiated neuronal precursor cells can be efficiently isolated from differentiating pluripotent embryonic cells in vitro, suggesting that this method can reproducibly provide homogeneous materials for further studies on neurogenesis.

Immediate mobilization following fixation of mandible fractures: a prospective, randomized study

OBJECTIVES

To compare outcomes of open reduction and internal fixation of displaced mandible fractures followed by either immediate mobilization or 2 weeks of mandibular-maxillary fixation.

STUDY DESIGN

A prospective, randomized, single-blinded study was performed.

METHODS

The study was performed between January 1, 1997, and March 30, 2000. Inclusion criteria were displaced fractures between the mandibular angles, age greater than 16 years, and no involvement of the alveolus, ramus, condyles, or maxilla. All fractures were repaired by means of open reduction and internal fixation using 2.0-mm titanium plates secured either in transoral fashion or percutaneously. Data were collected at 6-week and 3- and 6-month postoperative examinations. Variables were assessed by a surgeon blinded to the history of immobilization and included pain, malunion or nonunion, occlusion, trismus, wound status, infection rates, dental hygiene, and weight loss. Twenty-nine consecutive patients were enrolled, 16 patients to immediate function and 13 patients to 2 weeks of mandibular-maxillary fixation.

RESULTS

No statistically significant differences were found between groups for any of the variables. Immediate release and temporary immobilization showed mean weight loss of 10 and 8 pounds and trismus of 4.2 and 4.6 cm, respectively. One wound separation and one infection were seen in the immobilization population, and no wound separation or infection was seen in the immediate-release group. Dental hygiene was similar between the groups. No malunion or nonunion was noted in either group.

CONCLUSIONS

In this prospective and randomized study, no significant differences were noted between the groups receiving either immediate release or 2 weeks of mandibular-maxillary fixation. The findings support the treatment of selective mandible fractures with 2.0-mm miniplates and immediate mobilization.

False-positive growth of Mycobacterium tuberculosis attributable to laboratory contamination confirmed by restriction fragment length polymorphism analysis

SETTING

Despite the high prevalence of tuberculosis in Korea, false-positive cultures have not yet been reported. At Pusan National University Hospital, in which positive mycobacterial culture specimens were 2.8 daily on average, 12 specimens from 10 patients requested on the same day were positive for Mycobacterium tuberculosis.

OBJECTIVE

To identify an episode of laboratory cross-contamination in a tertiary care hospital.

DESIGN

All isolates were analyzed by restriction fragment length polymorphism, and patients' medical records were reviewed.

RESULTS

All isolates from 10 patients with supposed cross-contamination were identical. Anti-tuberculosis drugs were administered to two patients unnecessarily, resulting in adverse drug reactions in one patient. In one patient who had known tuberculous empyema, the medication course was probably lengthened unnecessarily.

CONCLUSIONS

An episode of laboratory cross-contamination in mycobacterial cultures occurred, possibly due to droplets splashed from a sample in a centrifuge tube. Consequently, the aerosol soiled the tip of the dispenser and contaminated the following specimens sequentially. This episode of laboratory cross-contamination resulted in some modifications in our methods of specimen processing and interpretation of the results.

Phenotyping cytochromes P450 with monoclonal antibodies

Monoclonal antibodies (MAbs) to cytochrome P-450 isozymes can be used to phenotype tissues for epitope-specific cytochrome P-450 content. MAbs that inhibit specific cytochrome P-450 dependent drug or carcinogen reactions are useful tools for quantitative measurement of the individual or classes of cytochromes P-450 that catalyze these reactions. This method has been applied successfully to animal as well as human tissues. Radioimmunoassays based on MAbs have been developed and provide a rapid and efficient means for detecting cytochromes P-450 independent of functional enzyme activity. In addition, MAbs coupled to a Sepharose support can be used to immunopurify cytochromes P-450 in a procedure that is more rapid and efficient than conventional purification schemes. MAbs add a new dimension to analyses of cytochrome P-450 multiplicity and will find numerous applications in elucidation of the relationship between cytochrome P-450 phenotype and carcinogen or drug metabolism.

Auricular reconstruction

Auricular defects occur from a variety of different causes and a wide array of reconstructive options are often necessary. This article presents a general algorithm for approaching the reconstruction of auricular defects. The spectrum of problems ranges from simple lacerations to superficial cutaneous defects to total avulsions. There are small tips that can help improve results with adjacent flaps as well as guidelines for total auricular reconstruction.

Umbilical arteritis and phlebitis mark different stages of the fetal inflammatory response

OBJECTIVE

Funisitis, the inflammation of the umbilical cord determined by histologic examination of the placenta, is evidence of a fetal inflammatory response. The inflammatory process may involve the umbilical vein (phlebitis) and one or both umbilical arteries (arteritis) and extend into the Wharton's jelly. This study was conducted to examine whether the pattern of inflammation of the umbilical cord correlates with a biochemical marker of systemic fetal inflammation (umbilical cord plasma interleukin-6) and an adverse neonatal outcome.

STUDY DESIGN

This cohort study included 636 cases of preterm delivery (<36 weeks) with or without inflammation of the umbilical cord. Umbilical cord blood was collected at the time of delivery. The aim of pathologic examination was to characterize the extent of umbilical cord inflammation and the involvement of the vein (phlebitis), the involvement of one or both arteries (arteritis), and the presence of inflammation of the Wharton's jelly. Umbilical cord plasma interleukin-6 concentrations were assayed by a sensitive and specific immunoassay.

RESULTS

Neonates with umbilical arteritis had a significantly higher median concentration of cord plasma interleukin-6 (median, 111 pg/mL; range, 0.1-19,230 pg/mL) than those without umbilical arteritis (median, 22.5 pg/mL; range, 0.9-511.6 pg/mL; P <.05). Also, severe neonatal morbidity occurred more frequently in infants with arteritis than in those without arteritis (74% vs 50%; P <.05). And finally, the most severe form of inflammation, which involves both arteries, vein, and Wharton's jelly, was associated with the highest median concentration of plasma interleukin-6 observed in this study (median, 182.6 pg/mL; range, 0.1-7,400 pg/mL), whereas inflammation limited to the vein (phlebitis) was associated with a lower concentration of cord plasma interleukin-6 (median, 29.1 pg/mL; range, 0.9-511.6 pg/mL; P <.05).

CONCLUSION

Neonates whose placenta demonstrates umbilical arteritis have higher concentrations of umbilical cord plasma interleukin-6 and higher rates of adverse outcome than those without umbilical arteritis.

The evolutionary chromosome translocation 4;19 in Gorilla gorilla is associated with microduplication of the chromosome fragment syntenic to sequences surrounding the human proximal CMT1A-REP

Many genomic disorders occur as a result of chromosome rearrangements involving low-copy repeats (LCRs). To better understand the molecular basis of chromosome rearrangements, including translocations, we have investigated the mechanism of evolutionary rearrangements. In contrast to several intrachromosomal rearrangements, only two evolutionary translocations have been identified by cytogenetic analyses of humans and greater apes. Human chromosome 2 arose as a result of a telomeric fusion between acrocentric chromosomes, whereas chromosomes 4 and 19 in Gorilla gorilla are the products of a reciprocal translocation between ancestral chromosomes, syntenic to human chromosomes 5 and 17, respectively. Fluorescence in situ hybridization (FISH) was used to characterize the breakpoints of the latter translocation at the molecular level. We identified three BAC clones that span translocation breakpoints. One breakpoint occurred in the region syntenic to human chromosome 5q13.3, between the HMG-CoA reductase gene (HMGCR) and RAS p21 protein activator 1 gene (RASA1). The second breakpoint was in a region syntenic to human chromosome 17p12 containing the 24 kb region-specific low-copy repeat-proximal CMT1A-REP. Moreover, we found that the t(4;19) is associated with a submicroscopic chromosome duplication involving a 19p chromosome fragment homologous to the human chromosome region surrounding the proximal CMT1A-REP. These observations further indicate that higher order genomic architecture involving low-copy repeats resulting from genomic duplication plays a significant role in karyotypic evolution.

Acute funisitis of preterm but not term placentas is associated with severe fetal inflammatory response

Acute funisitis, whose basic pathologic feature is umbilical vasculitis, constitutes a type of fetal inflammatory response to intrauterine infection. In the present study, a comparative analysis was performed between the clinicopathologic profiles of acute funisitis in term and preterm placentas along with measurement of fetal plasma interleukin 6 (IL-6) levels by specific immunoassay to assess the different biologic implications for the fetus. Acute funisitis in preterm placentas showed a significantly higher incidence of umbilical arteritis (P <.000001), higher fetal plasma IL-6 level (P <.0001), and higher prevalence of major perinatal morbidities (P <.0001). To assess the possible variation in fetal cell response to infectious agents according to gestational age, amnion cells and placental villous tissues obtained at different gestational ages were treated with bacterial lipopolysaccharides, and the IL-6 level of the culture media was assayed. Amnion cells and placental villous tissues from preterm placenta showed a more pronounced cytokine response than those from term placenta. The findings of this study indicate that the clinicopathologic significance of acute funisitis in term placentas is different from that of preterm placentas. Furthermore, they indicate that the robust inflammatory response of the fetus associated with elevated fetal plasma IL-6 level may reflect the biologic needs of the premature fetus to escape from the hostile intrauterine environment.

Purification and identification of N-glycolylneuraminic acid (Neu5Gc) from the holothuroidea Gumi, Cucumaria echinata

N-Glycolylneuraminic acid (Neu5Gc), precious sialic acid which could not be synthesized by a chemical method, occurrs in the body of holothuroidea, Gumi Cucumaria echinata. Gumi contains 85% of total sialic acid, as Neu5Gc, in the body. Neu5Gc was purified from dry powder of the body using Dowex 1-x8 (HCOO* form) anion exchange chromatography after mild acid hydrolysis with 0.1 N trifluoroacetic acid. Using GC-MS and 1H-NMR spectroscopy, the purified Neu5Gc was correctly identified to be Neu5Gc. The purity of Neu5Gc was more than 99%. This is the first report of purification and identification of Neu5Gc from holothuroidea by using anion exchange chromatography, GC-MS, and 1H-NMR.

Effect of omeprazole on the pharmacokinetics of moclobemide according to the genetic polymorphism of CYP2C19

BACKGROUND

Moclobemide, an antidepressant with selective monoamine oxidase-A inhibitory action, is known to be metabolized by CYP2C19 and is also reported to be an inhibitor of CYP2C19, CYP2D6, and CYP1A2. To confirm the involvement of CYP2C19, we performed a pharmacokinetic interaction study.

METHODS

The effect of omeprazole on the pharmacokinetics of moclobemide was studied in 16 healthy volunteers. The volunteer group comprised 8 extensive metabolizers and 8 poor metabolizers of CYP2C19, which was confirmed by genotyping. Subjects were randomly allocated into two sequence groups, and a single-blind, placebo-controlled, two-period crossover study was performed. In study I, a placebo was orally administered for 7 days. On the eighth morning, 300 mg of moclobemide and 40 mg of placebo were coadministered with 200 mL of water, and a pharmacokinetic study was performed. During study II, 40 mg of omeprazole was given each morning instead of placebo, and pharmacokinetic studies were performed on the first and eighth day with 300 mg of moclobemide coadministration.

RESULTS

The inhibition of moclobemide metabolism was significant in extensive metabolizers even after a single dose of omeprazole. After daily administration of omeprazole for 1 week, the pharmacokinetic parameters of moclobemide and its metabolites in extensive metabolizers changed to values similar to those in poor metabolizers. In poor metabolizers, no remarkable changes in the pharmacokinetic parameters were observed.

CONCLUSION

Our results show that CYP2C19 is an important enzyme in the elimination of moclobemide and that it is extensively inhibited by omeprazole in extensive metabolizers, but not in poor metabolizers.

Chemical composition and source apportionment of PM2.5 particles in the Sihwa area, Korea

To investigate the chemical characteristics of fine particles in the Sihwa area, Korea, atmospheric aerosol samples were collected using a dichotomous PM10 sampler and two URG PM2.5 cyclone samplers during five intensive sampling periods between February 1998 and February 1999. The Inductively Coupled Plasma (ICP)-Atomic Emission Spectrometry (AES)/ICP-Mass Spectrometry (MS), ion chromatograph (IC), and thermal manganese dioxide oxidation (TMO) methods were used to analyze the trace elements, ionic species, and carbonaceous species, respectively. Backward trajectory analysis, factor analysis, and a chemical mass balance (CMB) model were used to estimate quantitatively source contributions to PM2.5 particles collected in the Sihwa area. The results of PM2.5 source apportionment using the CMB7 receptor model showed that (NH4)2SO4 was, on average, the major contributor to PM2.5 particles, followed by nontraffic organic carbon (OC) emission, NH4NO3, agricultural waste burning, motor vehicle emission, road dust, waste incineration, marine aerosol, and others. Here, the nontraffic OC sources include primary anthropogenic OC emitted from the industrial complex zone, secondary OC, and organic species from distant sources. The source impact of waste incineration emission became significant when the dominant wind directions were from southwest and west sectors during the sampling periods. It was found that PM2.5 particles in the Sihwa area were influenced mainly by both anthropogenic local sources and long-range transport and transformation of air pollutants.

Translocation remodeling in the primary BALB/c plasmacytoma TEPC 3610

Myc-activating chromosomal 12;15 translocations, the hallmark mutations of inflammation-induced BALB/c plasmacytomas, have recently been shown to undergo remodeling by isotype switch-like genetic recombinations that remove approximately 180 kb of immunoglobulin heavy-chain sequence in the vicinity of the rearranged, expressed Myc gene. Here we combine cytogenetic data on the 12;15 translocation (SKY and FISH) with the molecular analysis of key junction sites (long-range PCR followed by DNA sequencing) to demonstrate that translocation remodeling occurred as an infrequent, stepwise, and disomic tumor progression event in the tetraploid, fully transformed, and transplantable plasmacytoma TEPC 3610. This result was used, in conjunction with previously obtained molecular data on five other primary plasmacytomas, to devise a hypothesis that predicts that the selective pressure to undergo translocation remodeling may be predetermined by the location of the break site in Myc. The pressure may be low if the break occurs 5' of the normal promoter region of Myc, but it may be considerably stronger if the break occurs 3' of the Myc promoter. Published 2001 Wiley-Liss, Inc.

A Korean family with a dominantly inherited beta-thalassemia due to Hb Durham-N.C./Brescia

We describe the molecular and the hematological characteristics of a Korean family with a dominantly inherited beta-thalassemia. Carriers were characterized by moderate anemia, hypochromia, microcytosis, elevated Hb A2 and Hb F levels, and splenomegaly. DNA analysis revealed a CTG (Leu) to CCG (Pro) substitution at codon 114 of the beta-globin gene, that leads to a highly unstable hemoglobin variant, Hb Durham-N.C./Brescia, and this was linked to the beta haplotype V, [+----+-], and framework 2. RNA analysis showed that the proband had comparable levels of mutant and normal beta-mRNA. Translation of the mutant mRNA would give rise to non-functional hyperunstable beta-globin chains, and their degradation would, by placing an additional burden on the proteolytic process of the red blood cell precursors, result in a more severe phenotype.