Total Synthesis and Cytotoxicity Evaluation of Pareitropone and Analogues

A concise synthesis of pareitropone by oxidative cyclization of a phenolic nitronate is delineated. The use of TMSOTf as an additive to promote the facile formation of a strained norcaradiene intermediate provides convenient access to highly condensed multicyclic tropones in high yields. This synthesis is modular, efficient, and scalable, highlighting the synthetic utility of radical anion coupling reactions in annulation reactions. This work is discussed in the context of total syntheses of the tropoloisoquinoline alkaloids. Also included are the preparation of several congeners and a brief description of their biological activities.

Genetic Analysis and Clinical Characteristics of Hereditary Pheochromocytoma and Paraganglioma Syndrome in Korean Population

BACKGROUND

Pheochromocytoma and paragangliomas (PPGL) are hereditary in approximately 30% to 40% cases. With the advancement of genetic analysis techniques, including next-generation sequencing (NGS), there were attempts to classify PPGL into molecular clusters. With NGS being applied to clinical settings recently, we aimed to review the results of genetic analysis, including NGS, and investigate the association with clinical characteristics in Korean PPGL patients.

METHODS

We reviewed the medical records of PPGL patients who visited Severance hospital from 2006 to 2019. We documented the clinical phenotype of those who underwent targeted NGS or had known germline mutations of related genes.

RESULTS

Among 57 PPGL patients, we found 28 pathogenic germline mutations of susceptibility genes. Before the targeted NGS was implemented, only obvious syndromic feature lead to the Sanger sequencing for the specific genes. Therefore, for the exact prevalence, only patients after the year 2017, when targeted NGS was added, were included (n=43). The positive germline mutations were found in 14 patients; thus, the incidence rate is 32.6%. Patients with germline mutations had a higher likelihood of family history. There were significant differences in the type of PPGLs, percentage of family history, metastasis rate, presence of other tumors, and biochemical profile among three molecular clusters: pseudohypoxic tricarboxylic acid cycle-related, pseudohypoxic von Hippel-Lindau (VHL)/endothelial PAS domain-containing protein 1-related, and kinase-signaling group. Germline mutations were identified in seven PPGL-related genes (SDHB, RET, VHL, NF1, MAX, SDHA, and SDHD).

CONCLUSION

We report the expected prevalence of germline mutations in Korean PPGL patients. NGS is a useful and accessible tool for genetic analysis in patients with PPGLs, and further research on molecular classification is needed for precise management.

Next-generation sequencing of BRCA1/2 in breast cancer patients: potential effects on clinical decision-making using rapid, high-accuracy genetic results

Purpose

We evaluated the clinical role of rapid next-generation sequencing (NGS) for identifying BRCA1/2 mutations compared to traditional Sanger sequencing.

Methods

Twenty-four paired samples from 12 patients were analyzed in this prospective study to compare the performance of NGS to the Sanger method. Both NGS and Sanger sequencing were performed in 2 different laboratories using blood samples from patients with breast cancer. We then analyzed the accuracy of NGS in terms of variant calling and determining concordance rates of BRCA1/2 mutation detection.

Results

The overall concordance rate of BRCA1/2 mutation identification was 100%. Variants of unknown significance (VUS) were reported in two cases of BRCA1 and 3 cases of BRCA2 after Sanger sequencing, whereas NGS reported only 1 case of BRCA1 VUS, likely due to differences in reference databases used for mutation identification. The median turnaround time of Sanger sequencing was 22 days (range, 14–26 days), while the median time of NGS was only 6 days (range, 3–21 days).

Conclusion

NGS yielded comparably accurate results to Sanger sequencing and in a much shorter time with respect to BRCA1/2 mutation identification. The shorter turnaround time and higher accuracy of NGS may help clinicians make more timely and informed decisions regarding surgery or neoadjuvant chemotherapy in patients with breast cancer.

Survey of Clinical Laboratory Practices for 2015 Middle East Respiratory Syndrome Coronavirus Outbreak in the Republic of Korea

Background

It is crucial to understand the current status of clinical laboratory practices for the largest outbreak of Middle East respiratory syndrome coronavirus (MERS-CoV) infections in the Republic of Korea to be well prepared for future emerging infectious diseases.

Methods

We conducted a survey of 49 clinical laboratories in medical institutions and referral medical laboratories. A short questionnaire to survey clinical laboratory practices relating to MERS-CoV diagnostic testing was sent by email to the directors and clinical pathologists in charge of the clinical laboratories performing MERS-CoV testing. The survey focused on testing volume, reporting of results, resources, and laboratory safety.

Results

A total of 40 clinical laboratories responded to the survey. A total of 27,009 MERS-CoV real-time reverse transcription PCR (rRT-PCR) tests were performed. Most of the specimens were sputum (73.5%). The median turnaround time (TAT) was 5.29 hr (first and third quartile, 4.11 and 7.48 hr) in 26 medical institutions. The median TAT of more than a half of the laboratories (57.7%) was less than 6 hr. Many laboratories were able to perform tests throughout the whole week. Laboratory biosafety preparedness included class II biosafety cabinets (100%); separated pre-PCR, PCR, and post-PCR rooms (88.6%); negative pressure pretreatment rooms (48.6%); and negative pressure sputum collection rooms (20.0%).

Conclusions

Clinical laboratories were able to quickly expand their diagnostic capacity in response to the 2015 MERS-CoV outbreak. Our results show that clinical laboratories play an important role in the maintenance and enhancement of laboratory response in preparation for future emerging infections.

Vitrfication and Slow Freezing for Cryopreservation of Germinal Vesicle-Stage Human Oocytes: A Bayesian Meta-Analysis

BACKGROUND

T he most commonly used methods for the cryopreservation of oocytes and embryos are vitrification and slow freezing.

OBJECTIVE

The aim of this study was to to investigate whether there are differences in survival, in vitro maturation (IVM), and fertilization rates between cryopreserved immature oocytes, especially germinal vesicle (GV)-stage human oocytes, following vitrification and slow freezing.

MATERIALS AND METHODS

A literature search was performed using the MEDLINE, Cochrane Central Register of Controlled Trials, and Embase databases. A total of three studies were included in the Bayesian meta-analysis.

RESULTS

There was no difference in survival rates between vitrification and slow freezing. Additionally, there was no difference in IVM rates and fertilization rates between vitrification and slow freezing.

CONCLUSION

The superiority of vitrification over slow freezing for cryopreservation of GV-stage human oocytes remains unclear. Additional studies on cytoarchitecture and modification of the cryopreservation protocol are essential to achieve strong conclusions.

Guidelines for the Laboratory Diagnosis of Middle East Respiratory Syndrome Coronavirus in Korea

The recent outbreak of Middle East respiratory syndrome (MERS) in Korea was unexpected that laboratory response had to be built up urgently during the outbreak. The outbreak was almost all healthcare-associated, which was aggravated by lack of availability in laboratory diagnosis of MERS-CoV on site. On behalf of the MERS joint public and private sector response committee (MERS Joint committee), the Korean Society for Laboratory Medicine (KSLM) launched a MERS response task force (MERS KSLM TF) to facilitate clinical laboratories set up MERS molecular diagnosis. MERS TF established guidelines for laboratory diagnosis of MERS-CoV and provided it to all participating laboratories as the official guidance of MERS Joint committee. This guideline was used for procedure manual of molecular diagnosis of MERS-CoV and laboratory safety manual.

A combination of excimer laser treatment and topical tacrolimus is more effective in treating vitiligo than either therapy alone for the initial 6 months, but not thereafter

BACKGROUND

There are insufficient data on the long-term outcome of a combination therapy that comprises phototherapy and topical administration of tacrolimus.

AIM

To evaluate the clinical efficacy according to the duration of treatment and in vitro results of a combination therapy involving topical tacrolimus and an excimer laser in the treatment of vitiligo.

METHODS

In total, 276 patients with nonsegmental vitiligo were treated with an excimer laser twice weekly, or with tacrolimus ointment twice daily, or both. The melanin contents and levels of melanogenic enzymes were measured in cultured human melanocytes treated with tacrolimus and/or excimer laser.

RESULTS

After adjusting for potential confounders, the combination of tacrolimus plus excimer laser was significantly more effective than either tacrolimus or excimer laser alone (P < 0.001 and P < 0.01, respectively) for the first 6 months. However, this superiority was not observed after the initial 6 months of treatment. In vitro, the combination of tacrolimus plus excimer laser led to a higher level of melanogenesis than with either treatment alone.

CONCLUSIONS

A combination treatment with topical tacrolimus and an excimer laser may be useful as an induction therapy for up to 6 months, but continuation of this therapy for > 6 months might not provide a better final outcome than monotherapy.

Human antibodies targeting the C-type lectin-like domain of the tumor endothelial cell marker clec14a regulate angiogenic properties in vitro

It has been suggested that clec14a may be involved in tumor angiogenesis. However, a molecular mechanism has not been clearly identified. In this study, we show for the first time that C-type lectin-like domain (CTLD) of clec14a may be important for regulating cell migration and filopodia formation. Using phage display technology, recombinant human antibodies specific to the CTLDs of human and mouse clec14a (clec14a-CTLD (immunoglobulin G) IgG) were selected. Functional assays using the antibodies showed that clec14a-CTLD IgGs specifically blocked endothelial cell migration and tube formation without affecting cell viability or activation. Further, clec14a-CTLD IgGs inhibited clec14a-mediated cell–cell contact by blocking interaction between CTLDs. Finally, clec14a cross-linking by the clec14a-CTLD IgGs significantly downregulated clec14a expression on the surface of endothelial cells. These results strongly suggest that the clec14a-CTLD may be a key domain in angiogenesis, and that clec14a-CTLD IgGs specifically inhibit angiogenesis by modulating CTLD-mediated cell interactions and clec14a expression on the surface of endothelial cells.

An engineered fibrinogen variant AαQ328,366P does not polymerise normally, but retains the ability to form α cross-links

A fibrin clot is stabilised through the formation of factor XIIIa-catalysed intermolecular ε-lysyl-γ-glutamyl covalent cross-links between α chains to form α polymers and between γ chains to form γ dimers. In a previous study we characterised fibrinogen Seoul II, a heterozygous dysfibrinogen in which a cross-linking acceptor site in Aα chain, Gln328, was replaced with Pro (AαQ328P). Following on the previous study, we investigated whether the alteration of Gln residues Aα328 and Aα366 affects fibrin polymerisation and α chain cross-linking. We have expressed three recombinant fibrinogens: AαQ328P, AαQ366P, and AαQ328,366P in Chinese hamster ovary cells, purified these fibrinogens from the culture media and performed biochemical tests to see how the introduced changes affect fibrin polymerisation and α chain cross-linking. Thrombin-catalysed fibrin polymerisation of all variants was impaired with the double mutation being the most impaired. In contrast, sodium dodecyl sulfate-polyacrylamide gel electrophoresis and immunoblot analysis showed α polymer formation with all three engineered proteins. This study demonstrates that AαQ328 and AαQ366 are important for normal fibrin clot formation and in the absence of residues AαQ328 and AαQ366, other Gln residues in the α chain can support FXIIIa-catalysed fibrin cross-linking.

Fibrinogen residue γAla341 is necessary for calcium binding and 'A-a' interactions

The fibrinogen γ-module has several important sites relating to fibrinogen function, which include the high affinity calcium binding site, hole 'a' that binds with knob 'A', and the D:D interface. Residue γAla341, which is located in the vicinity of these sites, is altered in three variant fibrinogens: fibrinogen Seoul (γAla341Asp), Tolaga Bay (γAla341Val), and Lyon III (γAla341Thr). In order to investigate the impaired polymerisation of fibrinogens γAla341Asp and γAla341Val to understand the role of γAla341 in fibrin polymerisation and fibrinogen synthesis, we have expressed γAla341Asp and γAla341Val in Chinese hamster ovary (CHO) cells, purified these fibrinogens from the culture media and performed biochemical tests to elucidate their function. Expression in CHO cells was similar for these variants. For both variants the kinetics of thrombin-catalysed FpA release was not different from normal fibrinogen, while FpB release was slower than that of normal. Thrombin-catalysed polymerisation of both variants was dependent on the calcium concentration. At physiologic calcium (1 mM) the variants showed impaired polymerisation with a longer lag period and a slower Vmax than normal fibrinogen. Scanning electron micrographs showed the clots were less organised than normal, having thicker and more twisted fibers, and larger pores. Analysis by SDS-PAGE showed that factor XIIIa-catalysed γ and α chain cross-linking was delayed, and plasmin-catalysed lysis was not reduced by the presence of 5 mM calcium or 5 mM GPRP (Gly-Pro-Arg-Pro). Our data indicate that fibrinogen residue γAla341 is important for the proper conformation of the γ-module, maintaining calcium-binding site and 'A-a' interactions.

A Gly1609Arg missense mutation in the vWF gene in a Korean patient with von Willebrand disease type 2A

We describe a case of a c.4825G>A (p.Gly1609Arg [Gly846Arg]) missense mutation in the gene encoding von Willebrand factor (vWF) in a Korean patient with von Willebrand disease (vWD) type 2A. The proband is a 37-year-old female who suffers from dysmenorrhea and menorrhagia. On laboratory testing, we found a low (0.01) vWF:RCo/Ag ratio, a decrease in high and intermediate molecular weight multimers from plasma, and abnormalities in the collagen binding capacity of plasma vWF, all of which were indicative of vWD type 2. Family studies revealed that her sister, son, and daughter also had a low vWF:RCo/ Ag ratio and a decrease in high molecular weight multimers from plasma. Genetic analyses showed that she and her three family members had the same heterozygous c.4825G>A (p.Gly1609Arg [Gly846Arg]) missense mutation. To our knowledge, this is the first report of the c.4825G>A (p.Gly1609Arg [Gly846Arg]) heterozygote mutation in Korean family members with vWD type 2A.

Rapid identification of thrombocytopenia-associated multiple organ failure using red blood cell parameters and a volume/hemoglobin concentration cytogram

Thrombocytopenia-associated multiple organ failure (TAMOF) has a high mortality rate when not treated, and early detection of TAMOF is very important diagnostically and therapeutically. We describe herein our experience of early detection of TAMOF, using an automated hematology analyzer. From 498,390 inpatients, we selected 12 patients suspected of having peripheral schistocytosis, based on the results of red blood cell (RBC) parameters and a volume/hemoglobin concentration (V/HC) cytogram. We promptly evaluated whether the individual patients had clinical manifestations and laboratory findings were consistent with TAMOF. Plasma exchanges were then performed for each patient. All 12 patients had TAMOF. The mean values of RBC parameters were significantly higher in all of the patients than with the reference range, however, 3 patients had % RBC fragments within the reference range. The mean value of ADAMTS-13 activity was slightly lower in patients compared with the reference range. Of the 12 patients, remission was obtained in 9 patients (75%) within 4 to 5 weeks using plasma exchanges. Three patients died. An increased percentage of microcytic hyperchromic cells with anisocytosis and anisochromia indicated the presence of schistocytes, making it an excellent screening marker for TAMOF. Identification of TAMOF with RBC parameters and a V/HC cytogram is a facile and rapid method along with an automated hematology analyzer already in use for routine complete blood cell counting test.

Osteolytic mandible presenting as an initial manifestation of an adult acute lymphoblastic leukaemia

A case of adult acute lymphoblastic leukaemia is reported. A 35-year-old male presented with an osteolytic lesion of the mandible. There was no definitive involvement in other craniofacial bones. A panoramic radiograph taken 4 months previously showed no bony involvement. A complete blood count showed a slightly decreased red blood cell count, but normal white blood cell count, white blood cell differential count and platelet count. Routine chemistry revealed hypercalcemia with an increased level of parathyroid hormone-related protein. Histopathological examination of bone marrow biopsy confirmed the diagnosis of acute lymphoblastic leukaemia.

A heparin binding site Arg79Cys missense mutation in the SERPINC1 gene in a Korean patient with hereditary antithrombin deficiency

We describe a case of heparin binding site Arg79Cys mutation in the gene encoding antithrombin, SERPINC1, in a Korean patient with hereditary antithrombin (AT) deficiency. The patient was a 34-year-old Korean man who presented with deep vein thrombosis (DVT) in his right leg without precipitating factors. On outpatient evaluation, coagulation tests without anticoagulation revealed a decreased AT III activity level at 48%, but normal AT III antigen level at 103%, indicating type II AT deficiency. Family studies revealed that his father (62 years of age) had decreased AT activity (48%) but had normal AT antigen levels (116%), indicating that the proband had a paternally inherited type II AT deficiency. Direct sequencing of the SERPINC1 gene in the patient and his father revealed a heterozygotic missense mutation, a cytosine to thymine substitution at nucleotide position 235 in exon 2 of the SERPINC1 gene (p.Arg79Cys). To our knowledge, this is the first report of Arg79Cys heterozygote mutation in family members with venous thromboembolism.

A rare splicing mutation in the PROS1 gene of a Korean patient with type I hereditary protein S deficiency

Hereditary protein S (PS) deficiency (Gene ID: 5627; MIM # 176880) is a notable risk factor for recurrent venous thrombosis, inherited as an autosomal-dominant trait, either homozygous or heterozygous. It may be caused by point mutations in the gene (PROS1) encoding PS, which contains 15 exons on the chromosome 3q11.2. Only a few point mutations associated with the PROS1 gene in patients with hereditary PS deficiency have been reported. A 60-year-old woman was admitted for deep vein thrombosis (DVT) of the right lower extremity. Upon coagulation examination, both the free PS antigen level and the total PS antigen level were decreased, so the DNA-PCR products of all 15 exons, including the exon-intron boundaries of the PROS1, gene were directly sequenced. A substitution from guanine to adenine at position +5 of the donor splice site of intron 10 (c.1155+5G>A) was identified. Further familial study was performed, and the patient's older sister was revealed to have the same mutation; she was already taking warfarin due to diagnosed pulmonary thromboembolism. Here we report a G to A transition at position +5 of intron 10 from the splice donor site as a rare case of a patient with type I hereditary PS deficiency in Korea.

Oxidative status in iron-deficiency anemia

Oxidative stress is an imbalance between free radicals and antioxidant molecules that can play an important role in the pathogenesis of iron-deficiency anemia (IDA). The aim of this study was to investigate oxidative status in patients with IDA and alteration of oxidative status after iron treatment. Thirty-three female patients with IDA and 25 healthy controls were included in this study. Oxidant and total antioxidant capacity were determined using free oxygen radicals test and free oxygen radicals defence (Form CR 3000, Callegari, Parma, Italy). Catalase activity was measured by spectrophotometer using a commercially available kit (Bioxytech Catalase-520, OxisResearch, Portland, OR). Oxidant activity in patients with IDA was significantly higher than controls (P<0.05), while total antioxidant and catalase activity were significantly lower (P<0.05). After treatment, oxidant, antioxidant, and catalase activity reached the levels of the control group, and no significant differences were observed among groups (P>0.05). In conclusion, our data indicate that blood reactive oxygen species was lower and total antioxidant and catalase activity were higher after rather than before treatment in patients with IDA. The results of our study support the higher oxidative stress hypothesis in IDA; however, due to the limited number of cases included, more studies may be required to confirm the results.

A novel de novo mutation in the serine-threonine kinase STK11 gene in a Korean patient with Peutz-Jeghers syndrome

Background

Peutz-Jeghers syndrome (PJS) is an unusual autosomal dominant disorder characterized by mucocutaneous pigmentation and multiple gastrointestinal hamartomatous polyps. Patients with PJS are at an increased risk of developing multi-organ cancer, most frequently those involving the gastrointestinal tract. Germline mutation of the STK11 gene, which encodes a serine-threonine kinase, is responsible for PJS.

Methods

Using DNA samples obtained from the patient and his family members, we sequenced nine exons and flanking intron regions of the STK11 gene using polymerase chain reaction (PCR) and direct sequencing.

Results

Sequencing of the STK11 gene in the proband of the family revealed a novel 1-base pair deletion of guanine (G) in exon 6 (c.826delG; Gly276AlafsX11). This mutation resulted in a premature termination at codon 286, predicting a partial loss of the kinase domain and complete loss of the C-terminal domain. We did not observe this mutation in both parents of the PJS patient. Therefore, it is considered a novel de novo mutation.

Conclusion

The results presented herein enlarge the spectrum of mutations of the STK11 gene by identifying a novel de novo mutation in a PJS patient and further support the hypothesis that STK11 mutations are disease-causing mutations for PJS with or without a positive family history.

A novel fibrinogen variant (fibrinogen Seoul II; AαGln328Pro) characterized by impaired fibrin α-chain cross-linking

We report a novel fibrinogen variant (fibrinogen Seoul II), which has a heterozygous point mutation from CAA to CCA leading to AαGln328Pro. The mutation site is among several glutamine residues that serve as α-chain cross-linking acceptor sites. Fibrinogen Seoul II was found in a 51-year-old male patient and his family in Seoul, Korea. The patient was diagnosed with myocardial infarction at age 43. Eight years later he was admitted to the emergency room due to recurrence of the disease, where he expired under treatment with tissue plasminogen activator (t-PA). Fibrin polymerization curves, made using purified fibrinogen from the patient's relatives, showed a decreased final turbidity, suggesting Seoul II fibrin clots are composed of thinner fibers. This supposition was verified using scanning electron microscopy. Alpha-polymer formation by the mutant fibrinogen upon thrombin treatment in the presence of factor XIII and calcium was distinctly impaired. This result confirms that the residue Aα328 plays a pivotal role in α-chain cross-linking.

A case of del(13)(q22) with multiple major congenital anomalies, imperforate anus and penoscrotal transposition

"13q-"syndrome is known to have widely variable manifestations, including retinoblastoma, mental & growth retardation, malformation of brain & heart, anal atresia, and anomalies of the face and limbs. Here we report a case of del(13)(q22) with multiple major congenital anomalies for the first time in Korea. The patient was born at 36(+4) weeks of pregnancy by caesarian section. Birth weight was 1490g. On examination the following features were noted: - imperforate anus, ambiguous genitalia (bifid scrotum, penoscrotal transposition, hypospadia), syndactyly of toes, absence of thumbs, abnormal facies (dolichocephaly, telecanthus, large low set ears, saddle nose, high arched palate, micrognathia). Neurocranial ultrasonography showed atrophy of the corpus callosum and multiple calcifications. He died at 14 days. Post-mortem autopsy findings showed cholestasis and fatty metamorphosis of liver, abnormal lobulation (Rt:2, Lt:1) and lymphangiectasis of the lung, VSD, ASD, PDA of heart, and acute tubular necrosis of kidney. Cytogenetic studies was confirmed to 46,XY,del(13) (q22) by Giemsa banded chromosomes from peripheral blood lymphocytes.

Homozygous VN (677C to T) and d/D (2756G to A) variants in the methylenetetrahydrofolate and methionine synthase genes in a case of hyperhomocysteinemia with stroke at young age

Hyperhomocysteinemia is known to be associated with an increased risk of myocardial infarction, stroke, peripheral arterial disease, and venous thrombosis. Gene polymorphisms in methylenetetrahydrofolate reductase (MTHFR) and methionine synthase (MS) may account for reduced enzyme activity and hyperhomocysteinemia. A recent study has documented evidence of polygenic regulation of plasma homocyteine. We report here on a case of occlusive stroke at young age and hyperhomocysteinemia with homozygous VN (677C to T) variant in the MTHFR gene as well as homozygous D/D (2756G to A) variant in the MS gene.

A novel silent substitution (C8516T) in exon 9 of the human PROC gene

Protein C is a vitamin K dependent serine protease zymogen, which has a regulatory influence over the coagulation cascade via the inhibition of factors Va and VIIIa. Hereditary protein C deficiency is associated with an increased risk of thromboembolic disease. A multitude of families displaying protein C (PROC) gene defects have been reported, and a number of DNA sequence polymorphisms are known to occur in the PROC gene. We have identified a previously undescribed silent substitution (C8516T) by direct DNA sequencing in a Korean patient with thrombosis and protein C deficiency. In addition, a rare T allelic frequency (0.016) was determined in 123 patients with acquired or hereditary protein C deficiency.

Structure-activity relationships of apio nucleosides as potential antiviral agents

Several types of novel apio nucleosides were synthesized starting from 1,3-dihydroxyacetone and evaluated for antiviral activity. Among compounds tested, amino substituted apio dideoxynucleosides exhibited anti-HBV activity, while thioapio dideoxynucleosides were found to be active against HIV-1. Apio dideoxydidehydro nucleosides showed moderate to potent anti-HCMV activity, but their bioisosteric thioapio dideoxydidehydro nucleosides did not exhibit any significant antiviral activity.

Evidence for two modes of allelic loss: multifocal analysis on both early and advanced gastric carcinomas

To assess the extent and the timing of allelic loss required for the progression of gastric carcinoma, the intratumoral distribution of loss of heterozygosity (LOH) was compared in early and advanced tumors: early loss is uniformly observed in all tumor areas and late loss is localized in parts of tumor tissue. Tumor sites (167 sites) obtained from 42 gastric carcinoma tissues (26 advanced cancers and 16 early cancers) were examined for LOH on chromosomes 5q, 9p, 13q, 17p, and 18q. By using two or three microsatellite markers for each chromosome arm, it was shown that of 29 tumors showing LOH in at least one tumor site, 15 (51.7%, 12 advanced and three early cancers) harbored multiple losses on three or more chromosome arms, and 89.4% (84 of 94) of these losses was uniformly found in all tumor sites tested. In the remaining 14 tumors (48.3%, eight advanced and six early tumors) with sporadic losses on one or two chromosome arms, 44% (11 of 25) of the losses were commonly shared among the sites tested. Such marked difference (P<0.001, Fisher's exact test) in the intratumoral distribution of multiple and sporadic LOH patterns proposes two distinct LOH subtypes: multiple losses (high LOH), occurring at an early stage with a few additional losses, and sporadic losses (low LOH), taking place relatively late during tumor progression. The multifocal LOH findings imply that, rather than being gradual, the allelic losses take place in two manners that are already determined at an early stage.

Luteoma of pregnancy: sonographic findings in two cases

Luteoma of pregnancy is a rare nonneoplastic tumor-like mass of the ovary that emerges during pregnancy and regresses spontaneously after delivery. It is usually asymptomatic and is found incidentally during a cesarean section or postpartum tubal ligation. However, luteomas can be hormonally active, with production of androgens resulting in maternal and fetal hirsutism and virilization. Less than 200 cases have been described in the literature, and none in radiologic journals. Recognition of this entity is important so that unnecessary oophorectomy, with concomitant risk to both the patient and the fetus, is avoided. In this report, we describe two cases of luteoma of pregnancy. The first case documents sequential ultrasonographic demonstration of a presumed luteoma of pregnancy in a patient who was seen with hirsutism during a second trimester pregnancy. The luteoma, serum androgen levels, and patient's condition improved after delivery. This case is unique in that although the mass significantly decreased in size post partum, it continued to be visualized 14 months post partum. The second case illustrates the pronounced cystic appearance that these classically described solid lesions can demonstrate because of extensive necrosis.

Prognostic implications of microsatellite genotypes in gastric carcinoma

Microsatellite alterations such as loss of heterozygosity (LOH) and microsatellite instability (MSI) are observed in most (70% to 80%) gastric carcinomas. To determine whether the microsatellite genotypes are correlated with clinicopathological features, 118 patients with gastric carcinomas were examined by using polymorphic microsatellite markers for LOH on 5 gastric cancer-associated chromosome arms and non-polymorphic BAT markers for MSI. Microsatellite genotypes were categorized as high-frequency MSI (MSI-H), high-level LOH (LOH-H), low-level LOH (LOH-L) and LOH non-detectable (LOH-N). A significant fraction of the MSI-H, LOH-H and LOH-L types was observed in intestinal-type gastric carcinomas, whereas the LOH-N type was highly associated with diffuse-type tumors (p = 0.00162). There was a close relationship between microsatellite genotype and TNM (tumor-node-metastasis) stage (p = 0. 001). Univariate analysis showed that patients of LOH-H or LOH-N types and those of MSI-H or LOH-L types correlated with poor and favorable survival, respectively, not only in all tumor stages (p = 0.0001) but also in stages II and III (p = 0.0271). It is likely that the major genotypes of gastric carcinomas can be placed into at least 4 microsatellite categories, thus allowing the construction of a comprehensive genetic classification useful for the prediction of diverse clinical courses.

Prognostic implications of microsatellite genotypes in gastric carcinoma

Microsatellite alterations such as loss of heterozygosity (LOH) and microsatellite instability (MSI) are observed in most (70% to 80%) gastric carcinomas. To determine whether the microsatellite genotypes are correlated with clinicopathological features, 118 patients with gastric carcinomas were examined by using polymorphic microsatellite markers for LOH on 5 gastric cancer-associated chromosome arms and non-polymorphic BAT markers for MSI. Microsatellite genotypes were categorized as high-frequency MSI (MSI-H), high-level LOH (LOH-H), low-level LOH (LOH-L) and LOH non-detectable (LOH-N). A significant fraction of the MSI-H, LOH-H and LOH-L types was observed in intestinal-type gastric carcinomas, whereas the LOH-N type was highly associated with diffuse-type tumors (p = 0.00162). There was a close relationship between microsatellite genotype and TNM (tumor-node-metastasis) stage (p = 0. 001). Univariate analysis showed that patients of LOH-H or LOH-N types and those of MSI-H or LOH-L types correlated with poor and favorable survival, respectively, not only in all tumor stages (p = 0.0001) but also in stages II and III (p = 0.0271). It is likely that the major genotypes of gastric carcinomas can be placed into at least 4 microsatellite categories, thus allowing the construction of a comprehensive genetic classification useful for the prediction of diverse clinical courses.

How to create an effective scientific exhibit: analysis of award-winning exhibits from the 1998 RSNA meeting

Although the most important component of an effective scientific exhibit is content, the way in which an exhibit is constructed can greatly influence its overall effectiveness. Choice of format should be determined by carefully analyzing the purpose of one's exhibit, expected audience, and data at hand, as well as type of meeting and funding. Depending on the type of data to be presented and available equipment and budget, the most appropriate style for a scientific exhibit may be a traditional mat board, computer-generated tiles or large-print backboard panel, traditional mat board with viewbox exhibit, matted transparency tiles with viewbox exhibit, or computer-generated large-film display. The authors analyzed 993 of 1, 041 (95.4%) scientific exhibits on display at the 84th RSNA Scientific Assembly and Annual Meeting and categorized each exhibit according to the following characteristics: display type and size, color scheme, display font size, and graphic styles. These characteristics were then correlated with scientific exhibit and design awards as well as invitations for submission to RadioGraphics. Chance of winning an award or being asked to publish the presentation in RadioGraphics was significantly increased for viewbox exhibits (compared with backboard panel exhibits) and for larger exhibits (compared with smaller exhibits).

A case of Klinefelter syndrome with retroperitoneal teratoma

Klinefelter syndrome (KS) is often associated with various neoplasms, especially germ cell tumors. Mediastinum is the most favored site of extragonadal germ cell tumors with KS, which is somewhat different from those without KS. The retroperitoneal germ cell tumor in KS is very rare. A five-month-old boy with an abdominal mass was found to have a retroperitoneal tumor. After surgical removal, he was diagnosed to have mature cystic teratoma. Cytogenetic study of his peripheral lymphocytes revealed that his karyotype was consistent with KS. This case suggests that patients with KS might be at risk of having germ cell tumors in sites other than mediastinum. It also suggests that all cases with these tumors should be screened for the presence of karyotypic abnormalities, and it might help to assess the exact correlation between germ cell tumors and KS, and to treat them accordingly.

Tissue plasminogen activator and plasminogen activator inhibitor-1 in human choledochal bile

Fibrinolytic properties have been detected in animal and human gallbladder (GB) bile. Plasminogen activator inhibitor-1 (PAI-1) has been reported in greater concentration in GB stone bile and may be a nucleating factor in the pathogenesis of GB stone formation. It is unknown whether or not human choledochal bile has similar properties, which could have a role in choledocholithiasis. The aims of this study were to determine the presence of fibrinolytic properties of human choledochal bile and to compare those properties among normal, acalculous, and calculous-infected choledochal bile. Tissue plasminogen activator (t-PA) and PAI-1 of choledochal bile were measured by enzyme linked immunosorbent assay in patients with cholangitis due to acalculous bile duct obstructions (n = 9), choledocholithiasis with cholangitis (n = 20), and normal bile (n = 7). The t-PA concentration of choledochal bile was no different among the three groups (acalculous-infected bile, median 4.61 ng/ml, and calculous-infected bile, 4.61 ng/ml, versus normal bile, 7.33 ng/ml). PAI-1 was detected in choledochal bile in significantly greater concentrations in patients with acalculous cholangitis due to bile duct obstructions and choledocholithiasis with cholangitis (acalculous-infected bile, median 0.36 ng/ml, and calculous-infected bile, 0.1 ng/ml, versus normal bile, 0.02 ng/ml, p < 0.05), but the bile concentration of PAI-1 was no different between the acalculous and calculous-infected choledochal bile. Human choledochal bile possesses t-PA and PAI-1. PAI-1 was present in greater concentrations in both acalculous and calculous-infected choledochal bile. Increased levels of PAI-1 may be an epiphenomenon of cholangitis rather than a factor in the pathogenesis of choledocholithiasis.

Relationship between intratumor histological heterogeneity and genetic abnormalities in gastric carcinoma with microsatellite instability

Microsatellite instability (MSI)-mutator phenotype variably targets microsatellite-like sequences in coding regions of cancer-related genes. Intratumor histological heterogeneity of gastric carcinoma with MSI was evaluated and found to be linked with the topographical distribution of MSI-associated mutations. One hundred fifty tumor sites derived from 51 gastric cancer patients were microdissected with respect to histological and topographical clonality. We found 11 gastric carcinomas with a high frequency of MSI, which were characterized by marked intratumor genetic heterogeneity arising from the progressive MSI-phenotype that was associated with frameshift mutations on multiple cancer-related genes. The 11 MSI-tumor cases manifested the MSI-phenotype in 34 of 36 tumor sites tested, but not in the remaining 2 sites. Most (88.2%, 30 of 34) MSI-positive sites and most (96.2%, 25 of 26) tumor sites harboring the frameshift mutations in transforming growth factor-beta receptor type II gene exhibited intestinal-type histology, whereas the 2 MSI-negative sites were found to be of diffuse-type histology without accompanying frameshift mutations. In 2 of 5 cases harboring E2F-4 frameshift mutations, glandular structures of intestinal-type tumor were likely to be variably differentiated in relation to the extent of the mutation, i.e., the number of mutated alleles and the size of deleted or inserted base pairs. Overall, the intratumor histological heterogeneity of gastric carcinoma with MSI was associated with the progressive frameshift mutations in transforming growth factor-beta receptor type II and E2F-4 genes.

A molecular model of a point mutation (Val297Met) in the serine protease domain of protein C

A heterozygous GTG to ATG (Val297Met) mutation was detected in a patient with inherited protein C deficiency and deep vein thrombosis. Cosegregation of the mutation with protein C deficiency was observed through a family pedigree study. Molecular models of the serine protease domains of wild type and mutant protein C were constructed by standard comparative method. Val 297 was found to be located in the hydrophobic core of the protein. Although the substitution of Met for Val does not greatly alter the hydrophobicity of the protein, it introduces a bulkier side chain, which yields steric hindrance between this residue and adjacent residues, such as Met364, Tyr393, Ile321, Ile323, and Val378. It seems that the Met can not fit into the tight packing into which it is trapped, thereby probably inducing misfolding and/or greater instability of the protein. Such misfolding and/or instability thereby eventually disturbs the catalytic triad, in consistent with the observed type I deficiency state.

von Willebrand disease with G4022A mutation (vWd Sungnam): a case report

A 10-year-old male patient affected by type 2 von Willebrand disease (vWD) and his family members were investigated by hemostatic and molecular genetic studies. The propositus, who experienced frequent bleeding episodes, was characterized by a normal level of von Willebrand factor (vWF) antigen (54%), reduced vWF ristocetin cofactor activity (5%), decreased factor VIII clotting activity (25%) and absent high molecular weight multimers in the plasma. An exon 28 fragment coding for the A1 and A2 domains was amplified by polymerase chain reaction and sequenced. We found a heterozygous mutation (G4022A), producing an additional PstI restriction site, which resulted in the substitution of Arg578Gln. Family studies, including the parents and a brother, were negative for this mutation and vWF abnormalities were not observed. We confirmed that G to A mutation in the region of the platelet glycoprotein Ib binding domain of vWF causes the qualitative type 2 defect in von Willebrand disease.

Lipocortin 1 binding sites on human T-cells: the population of cells with the binding sites is larger in CD8+ T-lymphocytes than in CD4+ T-lymphocytes

Lipocortin 1 (LC1) is believed to be a mediator of glucocorticoids in displaying anti-inflammatory and immune suppressive responses. The existence of specific LC1 binding sites (putative receptor) on monocytes and neutrophils has been reported. We have studied the distribution of LC1 binding sites in human peripheral blood leukocytes by flow cytometry. The population of cells with LC1 binding sites was much larger in monocytes than in lymphocytes in both rheumatoid arthritis patients (93.1 +/- 2.3% vs 8.8 +/- 1.0%) and healthy volunteers (97.0 +/- 0.9% vs 9.9 +/- 1.5%). The LC1 binding cell population was larger in CD8+ T-lymphocytes than in CD4+ T-lymphocytes in both healthy volunteers (26.4 +/- 4.5% vs 10.6 +/- 2.0%) and rheumatoid arthritis patients (28.8 +/- 4.7% vs 8.7 +/- 2.1%). No difference in LC1 binding cell populations was found between rheumatoid arthritis patients and healthy controls.

Functional comparison of native and recombinant human salivary histatin 1

Histatin 1 is a histidine-rich phosphoprotein present in human parotid saliva that possesses candidacidal activity and functions in mineralization by adsorbing to hydroxyapatite. The objective of the present study was to develop a system for recombinant production of histatin 1 and to examine the role of phosphorylation in the functional activities of this molecule. Native histatin 1 (containing a phosphoserine at residue 2) was purified from parotid saliva, whereas a bacterial expression system was used to produce a recombinant form of histatin 1 (re-Hst1) that lacked phosphorylated serine. Histatin 1 cDNA was inserted into the vector pGEX-3X, which expresses foreign genes as soluble fusion proteins attached to the carboxyl-terminus of glutathione S-transferase (GST). The GST/re-Hst1 fusion protein was isolated from cell lysates by affinity chromatography on glutathione (GSH)-Sepharose and digested with cyanogen bromide to separate re-Hst1 from the GST fusion partner. The digest was subjected to reversed-phase high-performance liquid chromatography on a C18 column, and re-Hst1 was eluted as a well-defined peak. The yield of re-Hst1 was 4 mg/L of bacterial culture. Amino-terminal sequencing and amino acid analysis confirmed the final product as re-Hst1. Sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) showed that native histatin 1 and re-Hst1 had the same apparent molecular weights, while cationic PAGE showed that re-Hst1 was more basic. Phosphate analysis indicated 1 mol phosphate/mol of native histatin 1, while re-Hst1 lacked any detectable phosphate. Re-Hst1 demonstrated candidacidal activity comparable to that of native histatin 1, but displayed substantially lower binding to hydroxyapatite. These results show that phosphorylation of histatin 1 at residue 2 contributes significantly to its ability to bind to hydroxyapatite.

Diagnostic efficacy of plasma urokinase-type plasminogen activator and plasminogen activator inhibitor-2 in differentiation of hepatocellular carcinoma from cirrhosis

We determined the plasma antigen levels of urokinase-type plasminogen activator(u-PA) and plasminogen activator inhibitor 2(PAI-2) in 41 patients with hepatocellular carcinoma and 28 patients with different stages of liver cirrhosis. No significant differences of u-PA and PAI-2 levels were calculated between the two groups of tumor patients (HCC) and liver cirrhosis without tumor (non-HCC). Within both study groups, no significant differences were found in u-PA and PAI-2 levels of the different Child categories. Discriminative functions of both u-PA and PAI-2 (total error count estimates of 43.1% and 43.6%, respectively), were low compared to that (29.0%) of alpha-fetoprotein (AFP). The combinations of AFP and u-PA lowered the total error rate (21.9%) more than that of each marker alone. However, whether plasma u-PA and PAI-2 may be considered as a risk factor further investigation was needed and our findings raise the question as to whether these markers could be considered as useful screening markers for earlier detection of HCC in liver cirrhosis because discriminant functions of u-PA and PAI-2 were not significant. Sensitivities and specificities of u-PA and PAI-2 were also not high enough, resulting in the ranges of total diagnostic efficiency from 43% to 50%, and, from 49% to 63%, respectively, at different cut-off values. No direct relationship was detected between AFP and u-PA, between AFP and PAI-2, and between u-PA and PAI-2.

Neutron capture therapy beams at the MIT Research Reactor

Several neutron beams that could be used for neutron capture therapy at MITR-II are dosimetrically characterized and their suitability for the treatment of glioblastoma multiforme and other types of tumors are described. The types of neutron beams studied are: 1) those filtered by various thicknesses of cadmium, D2O, 6Li, and bismuth; and 2) epithermal beams achieved by filtration with aluminum, sulfur, cadmium, 6Li, and bismuth. Measured dose vs. depth data are presented in polyethylene phantom with references to what can be expected in brain. The results indicate that both types of neutron beams are useful for neutron capture therapy. The first type of neutron beams have good therapeutic advantage depths (approximately 5 cm) and excellent in-phantom ratios of therapeutic dose to background dose. Such beams would be useful for treating tumors located at relatively shallow depths in the brain. On the other hand, the second type of neutron beams have superior therapeutic advantage depths (greater than 6 cm) and good in-phantom therapeutic advantage ratios. Such beams, when used along with bilateral irradiation schemes, would be able to treat tumors at any depth in the brain. Numerical examples of what could be achieved with these beams, using RBEs, fractionated-dose delivery, unilateral, and bilateral irradiation are presented in the paper. Finally, additional plans for further neutron beam development at MITR-II are discussed.