[Analysis of disease composition and primary surgical procedures in pediatric secondary glaucoma inpatients: a single-center study]

Objective: To analyze the disease composition and primary surgical procedures in pediatric inpatients with secondary glaucoma. Methods: A retrospective case series study was conducted. Clinical data of children aged≤16 years with secondary glaucoma who were admitted to the Zhongshan Ophthalmic Center, Sun Yat-sen University, between January 1, 2017, and December 31, 2021, were included. The patients were classified according to the Childhood Glaucoma Research Network (CGRN) classification system, and their diagnoses, underlying factors, gender, age of onset, affected eye(s), age and type of initial surgery, and ophthalmic examination data were analyzed. Statistical analysis was performed using Kruskal-Wallis rank sum test and χ2 test. Results: A total of 540 patients (744 eyes) were included in this study, comprising 319 males (59.1%) and 221 females (40.9%). Unilateral disease was observed in 336 cases (62.2%), while bilateral involvement was present in 204 cases (37.8%). The age of onset was 4.0 (0.0, 9.0) years, and the median age of the first anti-glaucoma surgery was 5.0 (0.7, 10.0) years. Among them, there were 195 cases (36.1%) of secondary glaucoma associated with non-acquired ocular anomalies (SCG-O), with a median age of onset of 0.0 (0.0, 4.0) years, and 97 of these cases (49.7%) were male. secondary glaucoma associated with non-acquired systemic disease or syndrome (SCG-S) were observed in 68 cases (12.6%), with a median age of glaucoma onset of 0.1 (0.0, 4.0) years, and 47 of these cases (69.1%) were male. Secondary glaucoma associated with acquired conditions (SCG-A) accounted for 192 cases (35.6%), with a median age of onset of 9.0 (5.0, 13.0) years, and 125 of these cases (65.1%) were male. There were 85 cases (15.7%) of secondary glaucoma following cataract surgery (SCG-C), with a median age of onset of 3.0 (0.8, 7.0) years, and 50 of these cases (58.8%) were male. Male patients were predominant in SCG-S and SCG-A, with 47 cases (69.1%) and 125 cases (65.1%), respectively (χ2=9.94, 17.52; P=0.002,<0.001). Except for SCG-O, all other types of pediatric secondary glaucoma predominantly affected only one eye: SCG-S in 52 cases (76.5%), SCG-A in 128 cases (66.7%), and SCG-C in 54 cases (63.5%) (χ2=19.06, 21.33, 6.22; all P<0.05). The highest proportion of SCG-O was attributed to congenital ectropion uveae (46 cases, 23.6%). Sturge-Weber syndrome was the most common SCG-S (45 cases, 66.3%), while SCG-A mostly resulted from trauma (59 cases, 30.8%) and corticosteroid use (56 cases, 29.2%). Trabeculectomy (211 eyes, 30.8%) and glaucoma drainage device implantation (197 eyes, 28.7%) were the most frequently performed primary surgical procedures. Conclusions: SCG-O and SCG-A were found to be common types of pediatric secondary glaucoma. The age of onset and the choice of primary anti-glaucoma surgical procedures varied among different types of pediatric secondary glaucoma. However, overall, trabeculectomy and glaucoma drainage device implantation were the primary surgical procedures predominantly employed.

[Clinical features of young inpatients with angle-closure glaucoma]

Objective: To analyze the composition of diagnosis in young inpatients with angle-closure glaucoma and to compare the clinical characteristics between primary angle-closure glaucoma (PACG) and secondary angle-closure glaucoma (SACG). Methods: This was a retrospective case series study. Angle-closure glaucoma patients aged 40 years or younger and hospitalized in Zhongshan Ophthalmic Center from January 2012 to December 2019 were included. The clinical diagnosis, gender, onset age, and results of general ophthalmic examination, A-scan ultrasonography measurements, ultrasound biomicroscopy, optical coherence tomography and visual field were recorded. The proportions and composition of PACG and SACG, as well as the misdiagnosis ratio, were analyzed. The onset age, visual acuity, visual field, and ocular parameters were compared between patients with PACG and SACG. Non-normally distributed data were represented by M (Q₁, Q₃). The difference between groups were compared by Mann-Whitney U test, Chi square test, and independent sample t test. Results: A total of 243 patients (243 eyes) were included in this study. The mean onset age was (28±9) years, and the male-to-female ratio was 1∶1.79. There were 93 patients (38.3%) in PACG group and 150 (61.7%) in SACG group. The age of PACG [34(28, 38)] was older than that of SACG [28(19, 34)], and the proportion of males in the SACG group (44.0%, 66/150) was significantly higher than that in the PACG group (22.6%, 21/93) (Z=-5.34, χ²=11.46; both P<0.01). Nanophthalmos (22.7%, 34 cases), autosomal recessive bestrophinopathy (ARB) (19.3%, 29 cases), uveitis (18.7%, 28 cases) and retinitis pigmentosa (14.0%, 21 cases) were the most common causes of SACG. The best corrected visual acuity (logarithm of the minimum angle of resolution) was 0.10 (0.00, 0.48) and 0.40 (0.06, 1.00), mean deviation of visual field was -8.07 (-27.49, -2.09) and -15.04 (-28.75, -5.97) dB, and subfoveal choroidal thickness was (452.3±130.7) and (396.3±120.9) μm in the PACG and SACG groups, respectively. The differences were statistically significant (Z=-4.86, -2.14; t=2.37; all P<0.05). There was no statistical difference in intraocular pressure, cup-to-disc ratio, extent of peripheral anterior synechia, central anterior chamber depth, lens thickness, mean retinal nerve fiber layer thickness between these two groups (all P>0.05). The misdiagnosis ratio was 10.7% (26/243) in all patients, while the misdiagnosis ratio of the SACG group (16.7%, 25/150) was higher than that of the PACG group (1.1%, 1/93) (χ²=14.61, P<0.001). Conclusions: PACG, nanophthalmos and ARB are the most common etiologies in young inpatients with angle-closure glaucoma. Compared to PACG, patients with SACG are younger, with worse visual acuity and more severe visual field defects, and easier to be misdiagnosed.

[Survey on the stunting of children under seven years of age in nine cities of China]

Objective: To survey the children under 7 years of age in nine cities of China for a better understanding of the current situation of childhood stunting. Methods: According to a stratified cluster sampling design, a cross-sectional survey on children under 7 years of age was carried out in 9 cities (Beijing, Harbin and Xi'an in northern China; Shanghai, Nanjing and Wuhan in central China; and Guangzhou, Fuzhou and Kunming in southern China) from June to November in 2016. A total of 110 499 children were recruited. Height of children was evaluated using the growth standards for Chinese children (2009 edition) .Children with height less than the 3rd percentile of the growth standards were considered as stunting, and children with height between the 3rd and 10th percentiles of the growth standards were considered as relatively short stature. Chi-square test was used for comparison between data of boys and girls, urban and suburban, as well as among different ages and regions. Results: Totally 113 084 children under 7 years of age should be investigated and actually 110 499 children were investigated, with a rate of 97.7%. The prevalence of stunting was 1.9% (2 141/110 499) among all the children. The prevalence of stunting in urban children (1.6%, 904/55 524) was lower than that in suburban children (2.3%, 1 237/54 975, χ(2)=56.246, P<0.01). The gender difference in stunting prevalence was not statistically significant (1.9% (1 121/57 921) in boys and 1.9% (1 020/52 578) in girls, χ(2)=0.003, P=0.965). The prevalence of stunting decreased with age for children younger than 3 years, from 1.8% (312/17 080) in 0-<1 year of age group to 1.2% (168/13 740) in 2-<3 years of age group, but increased to 2.2% (240/11 073) at 6-<7 years group. Comparison among different regions showed that the stunting prevalence in southern region was higher than those in the central and northern regions (0.9% (193/20 374) in northern urban, 0.8% (154/18 486) in central urban, and 3.3% (557/16 664) in southern urban children), showing a statistical significance (χ(2)=437.736, P<0.01); 1.1% (241/21 924) in northern suburban, 1.4% (227/16 775) in central suburban and 4.7% (769/16 276) in southern suburban children, showing a statistical significance (χ(2)=646.533, P<0.01). In urban areas, the difference between the central and northern regions showed no statistical significance (χ(2)=1.429, P=0.232) and the stunting prevalence of central Chinese children was slightly higher than that of northern Chinese children in suburban areas (χ(2)=5.130, P=0.024). Among the nine cities, the stunting prevalence of Guangzhou (6.1%, 613/10 019) was higher than those of other cities (χ(2)=1 559.64, P<0.01). Among the stunting children, 78.4% (1 679/2 141) were classified as borderline or mild and only 7.2% (154/2 141) were classified as severe. The prevalence of relatively short stature was 5.2% (5 721/110 499). Conclusions: The prevalence of stunting among children under 7 years of age in nine cities of China is low and most of the stunting children were classified as mild; the prevalence of stunting in suburban children is higher than that in urban children; the gender difference show no statistical significance; and the prevalence of stunting in southern Chinese children is higher than those in central and northern Chinese children.

P2564Levosimendan shortens action potential duration, decreases alternans threshold and prevents ventricular arrhythmia during therapeutic hypothermia in isolated rabbit hearts

Background

Therapeutic hypothermia (TH) increases the susceptibility to ventricular arrhythmias (VA) by prolonging action potential duration (APD) and facilitating arrhythmogenic spatially discordant alternans (SDA). The calcium sensitizer levosimendan has been reported to shorten APD by enhancing ATP-sensitive K current. We hypothesize that levosimendan might shorten the already prolonged APD during TH, decreasing SDA threshold, and prevent the occurrence of VA.

Methods

Langendorff-perfused isolated rabbit hearts were subjected to 15-min TH (30°C) followed by 30-min treatment with levosimendan (0.5 μM, n=9) or vehicle (n=8). Using an optical mapping system, epicardial APD was evaluated by S1 pacing. SDA threshold was defined as the longest pacing cycle length (PCL) that induced SDA phenomenon. Ventricular fibrillation (VF) inducibility was evaluated by burst pacing for 30 s using the shortest PCL that achieved 1:1 ventricular capture.

Results

Levosimendan shortened the ventricular APD (at PCL 300 ms, from 229±9 ms to 211±18 ms, p=0.02) and decrease the SDA threshold (from 327±88 ms to 311±68 ms, p=0.001) during TH. The VF inducibility was decreased by levosimendan from 39±30% at 30°C to 14±12% after levosimendan infusion. In control hearts, the APD (p=0.75), SDA threshold (p=ns) and VF inducibility (p=0.12) were not changed by vehicle during TH.

Conclusions

Levosimendan protects the hearts against VA during TH by shortening APD and decreasing SDA threshold. Enhancing ATP-sensitive K current with levosimendan might be a novel approach to prevent VA during TH.

[Influence of antiretroviral prophylaxis on growth of HIV-exposed uninfected infants]

Objective: To evaluate the influence of antiretroviral prophylaxis on the growth and development of HIV-exposed uninfected infants in Guangzhou. Methods: Data were from the national information system for prevention of mother-to-child transmission of HIV infection, syphilis and hepatitis B. After excluding death and perinatal HIV infection cases, 564 HIV-exposed uninfected infants were included. The infants were divided into three groups, nevirapine (NVP) group, zidovudine (AZT) group and untreated group. The influences of antiretroviral prophylaxis on the body weight and height of the HIV-exposed uninfected infants were analyzed by using generalized estimating equations. Results: The HIV-exposed uninfected infants at 1-month old had lower Z scores of body weight-for-age and body height-for-age than the World Health Organization's reference standard. The prevalence of wasting in AZT group (17.5%) was higher than that in NVP group (6.2%) for 1-month old infants. Taking NVP or AZT was a protective factor for Z score of body length-for-age (P<0.05). Intrauterine exposure to triple antiviral drugs was a risk factor for the Z scores of body weight-for-age and body length-for-age (P<0.05). Conclusion: The physical growth and development of HIV-exposed uninfected infants at 1-month old was not well, and HIV-exposed uninfected infants who taking AZT had a higher incidence of wasting. Attention should be paid to these infants.

[Association between both maternal pre-pregnancy body mass index/gestational weight gain and overweight/obesity children at preschool stage]

Objective: To investigate the association of both maternal pre-pregnancy body mass index (BMI) and gestational weight gain (GWG) with childhood overweight and adiposity in preschool children. Methods: A total of 4 303 preschool children aged 3-5 years were enrolled in our study during June and November 2016 in Guangzhou. Children defined as overweight and obesity were according to the criteria of WHO while weight status during maternal pre-pregnancy was using the China Adult Reference. Gestational weight gain was defined according to the Institute of Medicine guidelines. Results: After adjusting the possible confounding factors, results from the logistic regression analysis showed that both maternal pre-pregnancy overweight and obesity would increase the risk for both childhood overweight and obesity (OR=1.820, 95%CI: 1.368-2.422). The analysis of covariance results also showed that both maternal overweight and obesity before pregnancy and excessive maternal weight gain during pregnancy increased the BMI Z-score in children. Maternal GWG over the recommended level were associated with both the childhood overweight and obesity (OR=1.296, 95%CI: 1.007-1.667). Joint associations of pre-pregnancy BMI and inappropriate GWG were also noticed in the study. Stratified analysis was conducted in three groups according to the pre-pregnancy BMI of the mothers. Result showed that there was no statistical difference in the risks of either overweight or obesity in children (P>0.05). However, when compared to mothers with adequate pre-pregnancy higher BMI and adequate GWG, under the combination of high pre-pregnancy BMI and excessive GWG, their adverse effects on childhood overweight and obesity were much higher (OR=1.574, 95%CI: 1.029-2.409). Conclusions: Both high pre-pregnancy BMI and inappropriate GWG were associated with greater BMI of their offspring. Pregnant women should follow the appropriate weight gain program and help their children to prevent from becoming obese.

Imaging of cerebral α4β2* nicotinic acetylcholine receptors with (-)-[(18)F]Flubatine PET: Implementation of bolus plus constant infusion and sensitivity to acetylcholine in human brain

The positron emission tomography (PET) radioligand (-)-[(18)F]flubatine is specific to α4β2(⁎) nicotinic acetylcholine receptors (nAChRs) and has promise for future investigation of the acetylcholine system in neuropathologies such as Alzheimer's disease, schizophrenia, and substance use disorders. The two goals of this work were to develop a simplified method for α4β2(⁎) nAChR quantification with bolus plus constant infusion (B/I) (-)-[(18)F]flubatine administration, and to assess the radioligand's sensitivity to acetylcholine fluctuations in humans. Healthy human subjects were imaged following either bolus injection (n=8) or B/I (n=4) administration of (-)-[(18)F]flubatine. The metabolite-corrected input function in arterial blood was measured. Free-fraction corrected distribution volumes (VT/fP) were estimated with modeling and graphical analysis techniques. Next, sensitivity to acetylcholine was assessed in two ways: 1. A bolus injection paradigm with two scans (n=6), baseline (scan 1) and physostigmine challenge (scan 2; 1.5mg over 60min beginning 5min prior to radiotracer injection); 2. A single scan B/I paradigm (n=7) lasting up to 240min with 1.5mg physostigmine administered over 60min beginning at 125min of radiotracer infusion. Changes in VT/fP were measured. Baseline VT/fP values were 33.8±3.3mL/cm(3) in thalamus, 12.9±1.6mL/cm(3) in cerebellum, and ranged from 9.8 to 12.5mL/cm(3) in other gray matter regions. The B/I paradigm with equilibrium analysis at 120min yielded comparable VT/fP values with compartment modeling analysis of bolus data in extrathalamic gray matter regions (regional means <4% different). Changes in VT/fP following physostigmine administration were small and most pronounced in cortical regions, ranging from 0.8 to 4.6% in the two-scan paradigm and 2.8 to 6.5% with the B/I paradigm. These results demonstrate the use of B/I administration for accurate quantification of (-)-[(18)F]flubatine VT/fP in 120min, and suggest possible sensitivity of (-)-[(18)F]flubatine binding to physostigmine-induced changes in acetylcholine levels.

Additional chromosomal abnormalities in core-binding factor acute myeloid leukemia

Despite sharing a similar genetic abnormality, patients with core binding factor acute myeloid leukemia (CBF-AML), which is characterized by the presence of t(8;21) or inv(16)/t(16;16), show heterogeneous survival. Other molecular or cytogenetic factors are supposed to have an impact on the prognosis. We enrolled 24 CBF-AML patients to determine the impact of cytogenetic abnormality, and c-KIT, FLT3, NPM1, and CEBPA mutations on the prognosis. Only three patients had the c-KIT mutation (3/24, 12.5%) and one had the FLT3 mutation. However, over half of the patients (14/24) harbored additional cytogenetic changes, including ten with loss of sexual chromosomes (LOS) [all in the t(8;21) group], and six had additional abnormalities (two cases had both LOS and additional abnormalities). From this small-number study, no association was found between c-KIT mutation and survival and relapse rate. However, additional chromosome abnormalities had a significant association with relapse of the disease (P = 0.027). Stem cell transplant had a trend of benefitting patients after relapse (P = 0.065). This implies that chromosome abnormalities occur in CBF-AML and might take part in the heterogeneous nature of CBF-AML.

Development of primer pairs from diverse chloroplast genomes for use in plant phylogenetic research

Variation in the chloroplast DNA sequence is useful for plant phylogenetic studies. However, the number of variable sequences provided by chloroplast DNA for suggested genes or genomic regions in plant phylogenetic analyses is often inadequate. To identify conserved regions that can be used to design primers and amplify variable sequences for use in plant phylogenetic studies, the complete chloroplast genomic sequences of six plant species (including Oryza sativa, Arabidopsis thaliana, Glycine max, Lotus japonicus, Medicago truncatula, and Phaseolus vulgaris), searched from the taxonomy database of NCBI were investigated. A total of 93 conserved regions, 32 in large single copy and 61 in inverted repeat regions, were identified. A set of five primer pairs were designed according to the conserved sequences located in the psbA~trnK, psbB~psbH, rpl23~trnI, trnR~trnN, and trnY~trnD regions to amplify variable DNA fragments. An additional 18 plant accessions from 14 species were used to validate their utility. Each of the tested species could be distinguished by length polymorphisms of fragments amplified with the five primer pairs. trnR~trnN and rpl23~trnI amplified fragments specific to monocot and legume species, respectively. Three primer pairs located in the psbA~trnK, psbB~psbH, and trnR~trnN regions were applied to amplify variable DNA sequences for phylogenetic analysis using the maximum parsimony method. The consistent result between taxonomy and phylogenetic analysis on the variable sequences amplified with these three primer pairs was revealed. The five newly developed primer pairs are recommended as tools for use in the identification of plant species and in phylogenetic studies.

Prognostic implication of molecular aberrations in cytogenetically normal acute myeloid leukemia patients receiving allogeneic hematopoietic stem cell transplantation

Different molecular aberrations can be discriminated into certain prognostic subgroups in cytogenetically normal acute myeloid leukemia (CN-AML) patients but their impact on allogeneic hematopoietic stem cell transplantation (allo-HSCT) remains controversial and studies from Asian populations are lacking. Forty-two adult non-M3 AML patients receiving allo-HSCT from 2002 to 2009 in southern Taiwan were retrospectively reviewed for survey, 23 (54.7%) of whom were CN-AML. NPM1, FLT3-ITD, and CEBPA were analyzed. After a median follow-up of 104 weeks (range, 8 to 384), patients in the good risk group (harboring either NPM1 or CEBPA mutation without concurrent FLT3-ITD) showed a borderline worse overall survival (OS) compared with the intermediate/poor risk group (P = 0.08). Interestingly, a poorer OS was found in patients with the CEBPA mutation (P = 0.003) but not the NPM1 mutation (P = 0.96). No OS difference was found between patients with or without FLT3-ITD (P = 0.15). In patients receiving allo-HSCT at first remission, there was no significant OS benefit in the good risk group (P = 0.33). In patients receiving allo-HSCT beyond first remission, disease status played a major role (P = 0.006), irrespective of molecular aberrations. Allo-HSCT in good risk patients should be carefully evaluated in Taiwanese, especially in patients with the CEBPA mutation. Conversely, allo-HSCT should be considered in first remission in patients with an intermediate/poor risk, where it may overcome the adverse impact of FLT3-ITD. Disease status remained a main issue in patients receiving allo-HSCT beyond first remission.

Identification of candidate genes underlying an iron efficiency quantitative trait locus in soybean

Prevalent on calcareous soils in the United States and abroad, iron deficiency is among the most common and severe nutritional stresses in plants. In soybean (Glycine max) commercial plantings, the identification and use of iron-efficient genotypes has proven to be the best form of managing this soil-related plant stress. Previous studies conducted in soybean identified a significant iron efficiency quantitative trait locus (QTL) explaining more than 70% of the phenotypic variation for the trait. In this research, we identified candidate genes underlying this QTL through molecular breeding, mapping, and transcriptome sequencing. Introgression mapping was performed using two related near-isogenic lines in which a region located on soybean chromosome 3 required for iron efficiency was identified. The region corresponds to the previously reported iron efficiency QTL. The location was further confirmed through QTL mapping conducted in this study. Transcriptome sequencing and quantitative real-time-polymerase chain reaction identified two genes encoding transcription factors within the region that were significantly induced in soybean roots under iron stress. The two induced transcription factors were identified as homologs of the subgroup lb basic helix-loop-helix (bHLH) genes that are known to regulate the strategy I response in Arabidopsis (Arabidopsis thaliana). Resequencing of these differentially expressed genes unveiled a significant deletion within a predicted dimerization domain. We hypothesize that this deletion disrupts the Fe-DEFICIENCY-INDUCED TRANSCRIPTION FACTOR (FIT)/bHLH heterodimer that has been shown to induce known iron acquisition genes.

Uterine leiomyosarcoma metastasis to the breast

BACKGROUND

Uterine leiomyosarcoma is a rare female neoplasm with a high recurrent and metastatic rate. However, only a few cases have been reported on metastasis to the breast. The purpose of this work is to stress the role of follow-up and to increase physicians' awareness of such lesion. case: A 62-year-old female suffered from a breast nodule and multiple metastases six years after resection for uterine leiomyosarcoma. Pathology revealed a rare condition of uterine leiomyosarcoma with breast metastasis.

CONCLUSION

The case highlights the important role of long-term follow-up in uterine leiomyosarcoma and implies the necessity of tissue proof in patients with the disease.

Gene frequencies of the HPA-1 to HPA-13, Oe and Gov platelet antigen alleles in Taiwanese, Indonesian, Filipino and Thai populations

Human platelet antigen (HPA) systems consist of more than twelve bi-allelic antigen polymorphisms in which a base pair substitution leads to change in an amino acid of a glycoprotein expressed on the platelet. The neonatal alloimmune thrombocytopenia (NAIT), post transfusion purpura, and refractoriness to platelet transfusion can be induced by antibodies against human platelet antigens: e.g. HPA-1a, 3a, 4a, 5a, and Gova. HPA typing is essential for the diagnosis and treatment of a variety of diseases. We developed a PCR-based method to detect HPA-1 to HPA-13, Oe and Gov platelet alloantigens. In this method, the amplified PCR products were used to recognize the polymorphism after restriction enzyme digestions. Among 566 Taiwanese, 107 Indonesian, 100 Filipino and 137 Thai subjects studied, HPA-1a, 2a, 4a, 5a, 6a, 7aW, 8aW, 9a, 10a, 11a, 12a, 13a, Oea genes were present in every sample; while HPA-1b, 2b, 4b, 5b and 6b were rarely found. HPA-7aW, 8aW, 9, 10, 11, 12, 13, and Oea alleles were noted to be monomorphic only. HPA-3a/3b alleles had frequencies of 0.595/0.405, 0.505/0.495, 0.507/0.493, 0.530/0.470, while Gova/Govb of 0.462/0.538, 0.450/0.550, 0.463/0.537, 0.520/0.480 among Taiwanese, Indonesians, Thais and Filipinos respectively. The prevalence rates of HPA-1 to 13 in this study were also consistent with other previous reports using different methods. The alloimmunization due to Gov and HPA-3 antigens need to be emphasized in these populations.

Gene frequencies of the HPA-1 to HPA-8w platelet antigen alleles in Taiwanese, Indonesian, and Thai

Human platelet antigen (HPA) systems consist of more than eight biallelic antigen polymorphisms in which a base pair substitution leads to change in an amino acid of a glycoprotein expressed on the platelet. HPA typing is essential in the diagnosis and treatment for a variety of diseases. We developed a polymerase chain reaction (PCR)-based method to detect HPA-1 through HPA-8w. In this method, the amplified PCR products were used to recognize the polymorphism after restriction enzyme digestions. Among 295 Taiwanese, 107 Indonesian, and 137 Thai subjects studied, HPA-1a, 2a, 4a, 5a, 6a, 7aw, and 8aw genes were present in every sample tested. HPA-1b, 2b, 4b, 5b, and 6b were rarely found among subjects. Only monomorphic HPA-7aw and 8aw alleles were noted in the samples. HPA-3a and 3b alleles showed frequencies of 0.595/0.405, 0.504/0.496, and 0.507/0.493 in Taiwanese, Indonesian, and Thai subjects, respectively. Our report is the first PCR-based method to detect most of the HPA antigen variants in Taiwanese, Indonesian, and Thai. The genomic typing results were also confirmed by direct sequencing for uncertain and some representative cases. The prevalence rates of HPA-1, 2, 3, 4, and 5 in this study were also consistent with other previous reports using different methods.

Autologous peripheral blood stem cells harvesting in Kaohsiung Medical University Hospital

We report our clinical experience in autologous peripheral blood stem cells harvesting. A total of 40 patients with 112 apheresis procedures were analyzed, 88 with Cobe system and 24 with MCS3P system. Our results revealed that there was no significant difference in efficiency of CD34(+) cell harvesting between both apheresis systems, but the Cobe system had more nucleated cells collected and less red cell contaminated in the final PBSCs collections. The percentage of CD34(+) cells collected decreased significantly following the first day's harvesting (p = 0.026). There was a good correlation between the percentage of CD34(+) cells in PBSCs and colony forming units-granulocyte macrophage (CFU-GM) or burst forming unit-erythrocyte (BFU-E)(r = 0.909, p < 0.0001; r = 0.788, p < 0.0001, respectively). However, it was negatively correlated with the patient's age. The CD34(+) cells collected in patients with acute leukemias were also higher than those patients with other solid tumors. Ten cases (13%) with 15 apheresis procedures experienced side effects like numbness, nausea, fever, or headache etc. The Cobe system seemed to have higher frequency of side effects than that of MCS3P system (16% vs 4%). From our results, we concluded that both COBE and MCS3P system have similar efficiency and all patients could tolerate the apheresis procedures in peripheral blood stem cells harvesting. The CD34(+) cell can be used as a good parameter to estimate the amount of stem cells collected. The patient's age and disease pattern were significant factors influencing the CD34(+) stem cells collection in autologous peripheral blood stem cells harvesting.

[Isolation of a kind of endophytic fungus which can produce taxol compounds]

OBJECTIVE

To isolate a kind of endophytic fungus which can produce taxol compounds from the bark of Taxus Cuspidata Sieb et Zucc.

METHODS

Endophytic fungus was isolated from the bark of Taxus Cuspidata Sieb et Zucc by aseptic techniques and the analysis of the culture fluid from the fermentation of fungus was carried out by high performance liquid chromatography (HPLC).

RESULTS

Endophytic fungus was obtained from the bark of Taxus Cuspidata Sieb et Zucc and the chemical analysis showed that the culture of fungus contain taxol compounds.

CONCLUSION

Endophytic fungus which can produce taxol compounds exists in the bark of Taxus Cuspidata Sieb et Zucc.

A molecular genetic analysis of the Kidd blood group polymorphism in Taiwanese, Thais, and Filipinos

In this study, we molecularly detect the Jka/Jkb polymorphism in Taiwanese, Thais, and Filipinos with PCR-restriction enzyme digestion. We designed the primers with mutagenic bases to create two restriction enzyme cutting sites (EcoN I and Xba I) simultaneously to confirm the genetic polymorphism of Jka/Jkb. One hundred and seven unrelated Taiwanese, 107 Thais foreign laborers, and 102 Filipino foreign laborers in Taiwan were analyzed. The frequency of Jka and Jkb is 0.51 and 0.49 in Taiwanese, 0.44 and 0.56 in Thais, and 0.45 and 0.55 in Filipinos, respectively. The molecular analysis of Jka/Jkb polymorphism is simple, accurate and could confirm the uncertain results obtained by serological typing. The method could be used for predicting fetal Kidd genotype from amniocyte DNA, and to avoid the hemolytic disease of newborns caused by Jk antibody.

Spatial heterogeneity of calcium transient alternans during the early phase of myocardial ischemia in the blood-perfused rabbit heart

BACKGROUND

Optical mapping of cytosolic calcium transients in intact mammalian hearts is now possible using long-wavelength [Ca(2+)](i) indicators. We propose that beat-to-beat [Ca(2+)](i) transient alternans during ischemia may lead to spatial and temporal heterogeneity of calcium-activated membrane currents.

METHODS AND RESULTS

To test this hypothesis, isolated rabbit hearts were loaded with the fluorescent [Ca(2+)](i) indicator, rhod-2 AM, and imaged at 300 frames/sec during blood-perfused ischemic trials. High-quality [Ca(2+)](i) transients were recorded in each of 8 hearts.[Ca(2+)](i) transient alternans was never present in control records but occurred in each of the hearts during ischemia, with onset after 2 to 4 minutes. Alternans was confined to circumscribed regions of the heart surface 5 to 15 mm across. Multiple regions of alternans were found in most hearts, and regions that were out of phase with one another were found in 6 hearts. Quantitative maps of alternans were constructed by calculating an alternans ratio. This ratio behaved as a continuous variable that reached a maximum value in the center of the regions with alternans.

CONCLUSIONS

These results demonstrate marked spatial heterogeneity of the [Ca(2+)](i) transient during the early phase of ischemia, which could produce electrical instability and arrhythmias in large mammalian hearts.

Risk factors for ICU mortality in critically ill patients

BACKGROUND AND PURPOSE

Advances in critical care medicine have increased the chances of survival for patients with severe illness or trauma. However, such patients consume a large proportion of medical resources. This study sought risk factors for mortality that have potential to be modified among patients treated in medical or surgical intensive care units (ICUs).

METHODS

This 6-month prospective observational study was conducted in the medical and surgical ICUs of an 1,800-bed university hospital. All adult patients with an expected ICU stay of 48 hours or more were followed up regularly until discharge from the ICUs, or for 10 weeks during their stay in ICUs.

RESULTS

Of 342 patients enrolled, 77 (22.5%) died during a median follow-up period of 5 days (range, 2-70 days). Among a range of variables at the time of ICU entry or developing during stay in ICUs, 17 were associated with higher mortality rate. Multivariate analysis using a logistic regression model demonstrated that the presence of systemic inflammatory response syndrome (SIRS) at the time of ICU entry (adjusted relative risk, ARR, 2.85; 95% confidence interval, CI, 1.16-7.05), Acute Physiological and Chronic Health Evaluation (APACHE) II score on ICU Day 4 (ARR 1.12 with increment of one score; 95% CI 1.01-1.24), Therapeutic Intervention Scoring System (TISS) score on Day 4 (ARR 1.13 with increment of one score; 95% CI 1.05-1.23), parenteral nutrition (ARR 4.97, 95% CI 1.73-14.26), and nosocomial Candida infection (ARR 3.39, 95% CI 1.12-10.23) were independently associated with ICU mortality.

CONCLUSIONS

In addition to SIRS and the APACHE II and TISS scores, this study found that nosocomial Candida infection and parenteral nutrition were independently associated with mortality after control for admission conditions, severity of illness scores, and interventions.

CD34+ stem cell transplantation in malignancies: report of three cases

Purging tumor cells from peripheral blood stem cells (PBSCs) used to treat patients with malignancy is important in the prevention of relapse. Positive selection of CD34+ stem cells using either immunomagnetic methods or an avidin-biotin conjugated CD34 monoclonal antibody binding column can reduce the number of contaminating tumor cells. We describe the management of three patients with malignancy treated using high-dose chemotherapy and enriched CD34+ cell transplantation. PBSCs were mobilized with cyclophosphamide plus recombinant granulocyte-colony stimulating factor (rG-CSF), and then leukophoresis was performed to harvest the PBSCs. The collected cells were positively selected for CD34+ cells using the Cellpro system. The CD34(+)-enriched PBSCs were then cryopreserved in the vapor phase of liquid nitrogen for future reinfusion. All three patients recovered smoothly after transplantation. The mean time to full hematologic recovery was 12 days for white blood cells (> or = 1 x 10(9)/L) and 14 days for platelets (> or = 20 x 10(9)/L), respectively. Partial remission occurred in two patients who were disease free for more than 4 years, and in one patient who died of hepatic failure with liver cirrhosis 5.5 months posttransplantation.

Tellurium-bridged manganese carbonyl clusters: synthesis and structural transformations of [Te4Mn3(CO10]-, [Te2Mn3(CO)9]2-, [Te2Mn3(CO)9]-, and [Te2Mn4(CO)12]2-

The reactions of appropriate ratios of K2TeO3 and [Mn2(CO)10)] in superheated methanol solutions lead to a series of novel cluster anions [Te4Mn3(CO)10] (1), [Te2Mn3(CO)9]2- (2), [Te2Mn3(CO)9]- (3), and [Te2Mn4(CO)12]2- (4). When cluster 1 is treated with [Mn2(CO)10]/KOH in methanol, paramagnetic cluster 2 is formed in moderate yield. Cluster 2 is oxidized by [Cu(MeCN)4]BF4 to give the closo-cluster [Te2Mn3(CO)9]- (3), while treatment of 2 with [Mn2(CO)10]/KOH affords the closo-cluster 4. IR spectroscopy showed that cluster 1 reacted with [Mn2(CO)10] to give cluster 4 via cluster 2. Clusters 1-4 were structurally characterized by spectroscopic methods or/and X-ray analyses. The core structure of 1 can be described as two [Mn(CO)3] groups doubly bridged by two Te2 fragments in a mu2-eta2 fashion. Both [Mn(CO)3] groups are further coordinated to one [Mn(CO)4] moiety. Cluster 2 is a 49 e- species with a square-pyramidal core geometry. While cluster 3 displays a trigonal-bipyramidal metal core, cluster 4 possesses an octahedral core geometry.

Optical mapping of ventricular defibrillation in isolated swine right ventricles: demonstration of a postshock isoelectric window after near-threshold defibrillation shocks

BACKGROUND

Investigators who studied ventricular defibrillation by use of optical mapping techniques failed to observe an initial defibrillation event (isoelectric window or quiescent period) shown by electrode mapping studies. This discrepancy has important implications for the mechanisms of defibrillation. The purpose of the present study was to demonstrate an optical equivalent of an isoelectric window after a near-threshold defibrillation shock. Methods and Results-- We studied 10 isolated, perfused swine right ventricles. Upper limit of vulnerability was determined by shocks on T waves. A 50% probability of successful defibrillation (DFT50) was determined with an up-down algorithm. Immediately after unsuccessful defibrillation shock, new wavefronts were generated. When the shock strength was low, immediate reinitiation of reentry and ventricular fibrillation might occur without a postshock isoelectric window. However, if the shock strength was within 50 V of DFT50 (near-threshold), a synchronized activation occurred, followed by organized repolarization that ended 64+/-18 ms after shock. After a period of quiescence (18+/-24 ms), activation recurred 83+/-33 ms after shock and reinitiated ventricular fibrillation. Similar patterns of activation, including a quiescent period, were observed after shock was applied on the T wave of the paced beat that induced ventricular fibrillation. Upper limit of vulnerability correlated well with DFT50.

CONCLUSIONS

In isolated swine right ventricles, an optical equivalent of an isoelectric window exists after near-threshold defibrillation shocks. These findings support the idea that a near-threshold defibrillation shock terminates all activation wavefronts but fails to halt ventricular fibrillation because the same shock reinitiates ventricular fibrillation after an isoelectric window.

Patterns of wave break during ventricular fibrillation in isolated swine right ventricle

Several different patterns of wave break have been described by mapping of the tissue surface during fibrillation. However, it is not clear whether these surface patterns are caused by multiple distinct mechanisms or by a single mechanism. To determine the mechanism by which wave breaks are generated during ventricular fibrillation, we conducted optical mapping studies and single cell transmembrane potential recording in six isolated swine right ventricles (RV). Among 763 episodes of wave break (0.75 times x s(-1) x cm(-2)), optical maps showed three patterns: 80% due to a wave front encountering the refractory wave back of another wave, 11.5% due to wave fronts passing perpendicular to each other, and 8.5% due to a new (target) wave arising just beyond the refractory tail of a previous wave. Computer simulations of scroll waves in three-dimensional tissue showed that these surface patterns could be attributed to two fundamental mechanisms: head-tail interactions and filament break. We conclude that during sustained ventricular fibrillation in swine RV, surface patterns of wave break are produced by two fundamental mechanisms: head-tail interaction between waves and filament break.

Effects of diacetyl monoxime and cytochalasin D on ventricular fibrillation in swine right ventricles

Whether or not the excitation-contraction (E-C) uncoupler diacetyl monoxime (DAM) and cytochalacin D (Cyto D) alter the ventricular fibrillation (VF) activation patterns is unclear. We recorded single cell action potentials and performed optical mapping in isolated perfused swine right ventricles (RV) at different concentrations of DAM and Cyto D. Increasing the concentration of DAM results in progressively shortened action potential duration (APD) measured to 90% repolarization, reduced the slope of the APD restitition curve, decreased Kolmogorov-Sinai entropy, and reduced the number of VF wave fronts. In all RVs, 15-20 mmol/l DAM converted VF to ventricular tachycardia (VT). The VF could be reinduced after the DAM was washed out. In comparison, Cyto D (10-40 micromol/l) has no effects on APD restitution curve or the dynamics of VF. The effects of DAM on VF are associated with a reduced number of wave fronts and dynamic complexities in VF. These results are compatible with the restitution hypothesis of VF and suggest that DAM may be unsuitable as an E-C uncoupler for optical mapping studies of VF in the swine RVs.

Marek's disease virus (MDV) encodes an interleukin-8 homolog (vIL-8): characterization of the vIL-8 protein and a vIL-8 deletion mutant MDV

Chemokines induce chemotaxis, cell migration, and inflammatory responses. We report the identification of an interleukin-8 (IL-8) homolog, termed vIL-8, encoded within the genome of Marek's disease virus (MDV). The 134-amino-acid vIL-8 shares closest homology to mammalian and avian IL-8, molecules representing the prototype CXC chemokine. The gene for vIL-8 consists of three exons which map to the BamHI-L fragment within the repeats flanking the unique long region of the MDV genome. A 0.7-kb transcript encoding vIL-8 was detected in an n-butyrate-treated, MDV-transformed T-lymphoblastoid cell line, MSB-1. This induction is essentially abolished by cycloheximide and herpesvirus DNA polymerase inhibitor phosphonoacetate, indicating that vIL-8 is expressed with true late (gamma2) kinetics. Baculovirus-expressed vIL-8 was found to be secreted into the medium and shown to be functional as a chemoattractant for chicken peripheral blood mononuclear cells but not for heterophils. To characterize the function of vIL-8 with respect to MDV infection in vivo, a recombinant MDV was constructed with a deletion of all three exons and a soluble-modified green fluorescent protein (smGFP) expression cassette inserted at the site of deletion. In two in vivo experiments, the vIL-8 deletion mutant (RB1BvIL-8DeltasmGFP) showed a decreased level of lytic infection in comparison to its parent virus, an equal-passage-level parent virus, and to another recombinant MDV containing the insertion of a GFP expression cassette at the nonessential US2 gene. RB1BvIL-8DeltasmGFP retained oncogenicity, albeit at a greatly reduced level. Nonetheless, we have been able to establish a lymphoblastoid cell line from an RB1BvIL-8DeltasmGFP-induced ovarian lymphoma (MDCC-UA20) and verify the presence of a latent MDV genome lacking vIL-8. Taken together, these data describe the identification and characterization of a chemokine homolog encoded within the MDV genome that is dispensable for transformation but may affect the level of MDV in vivo lytic infection.

Experimental and theoretical analysis of phase singularity dynamics in cardiac tissue

INTRODUCTION

Quantitative analysis of complex self-excitatory wave patterns, such as cardiac fibrillation and other high-order reentry, requires the development of new tools for identifying and tracking the most important features of the activation, such as phase singularities.

METHODS AND RESULTS

Image processing operations can be used to detect the phase singularity at the tip of a spiral wave. The phase space behavior of a spatiotemporal sequence of data may be reconstructed using time-series analysis. The phase singularities then are localized efficiently by computing the topologic charge density as the curl of the spatial phase gradient. We analyzed the singularity interaction dynamics of both experimentally observed and numerically simulated instances of quatrefoil reentry and found that the singularity behavior in the experimental preparations can be classified into three categories on the basis of how their separation changes with time.

CONCLUSION

Topologic charge densities can be calculated easily and efficiently to reveal phase singularity behavior. However, the differences between theoretical and experimental observations of singularity separation distances indicate the need for more sophisticated numerical models.

Dynamics of intramural and transmural reentry during ventricular fibrillation in isolated swine ventricles

The intramural dynamics of ventricular fibrillation (VF) remain poorly understood. Recent investigations have suggested that stable intramural reentry may underlie the mechanisms of VF. We performed optical mapping studies of VF in isolated swine right ventricles (RVs) and left ventricles (LVs). Nine RV walls were cut obliquely in their distal edge exposing the transmural surface. Six LV wedge preparations were also studied. Results showed that intramural reentry was present. In RV, 28 of 44 VF episodes showed reentry; 15% of the activation pathways were reentrant. Except for 4 episodes, reentry was transmural, involving subendocardial structures as the papillary muscle (PM) or trabeculae. In LV, reentry was observed in 27 of 27 VF episodes; 23% of the activations were part of reentrant pathways (P<0.05 compared with RV). All LV reentrant pathways were truly intramural (confined to the wall) and were frequently located at the PM insertion. In both ventricles, reentry was spatially and temporally unstable. Histological studies showed abrupt changes in fiber orientation at sites of reentry and wave splitting. Connexin 40 immunostaining demonstrated intramyocardial Purkinje fibers at sites of reentry in the PM root and around endocardial trabeculae. Our results confirm that reentry is frequent-but unstable-in the myocardial wall during VF. In RV, reentry is mostly transmural and requires participation of subendocardial structures. The LV has a greater incidence of reentry and is intramural. Anisotropic anatomic structures played key roles in the generation of wave splitting and in the maintenance of reentry.

Efficacy of a mass hepatitis B immunization program after switching to recombinant hepatitis B vaccine: a population-based study in Taiwan

To study the efficacy of immunization against hepatitis B after plasma-derived vaccine was replaced by recombinant vaccine, 2-year-old Taiwanese children were recruited by stratification random sampling and tested for hepatitis B markers. They were grouped according to maternal infectivity and children's immunization status. Of 2010 children, 2.5% had hepatitis B surface antigen (HBsAg), 94.1% had its antibody (anti-HBs), 6.8% had core antibody, and 3.3% were seronegative. Children of highly infectious mothers immunized with hepatitis B immunoglobulin and vaccine on schedule had a lower HBsAg-positive rate and a higher anti-HBs-positive rate than those with vaccine only and off-schedule. The efficacy of the Taiwanese mass hepatitis B immunization was maintained after switching to recombinant hepatitis B vaccine.

Altered cellular but not humoral reactions in children with complicated enterovirus 71 infections in Taiwan

Enterovirus 71 (EV 71) infections have high neurovirulence and fatality. Immune responses were assessed in 78 patients with EV 71 infection. EV 71 meningoencephalitis occurred more frequently in younger children and in boys. C-reactive protein levels were not elevated, although total leukocyte counts were increased in these patients. The CD40-ligand expression on T cells significantly decreased in children with meningoencephalitis (P=.041). Polymorphism of the cytotoxic T lymphocyte antigen-4 (CTLA-4) at position 49 of exon 1 showed a higher frequency of G/G genotype in patients with EV 71 meningoencephalitis than in those without meningoencephalitis (18/31 vs. 14/47; P=.045) and in control subjects (18/31 vs. 25/93l; P=.007). Specific EV 71 neutralizing antibody titers were detectable but did not differ in children with and without meningoencephalitis in the acute and convalescent stages. Results from this study suggest that younger children with a certain CTLA-4 polymorphism and altered cellular but not humoral response may be linked to EV 71 meningoencephalitis.

Secondary chronic myelogenous leukemia after autologous peripheral blood stem cell transplantation for Lymphoma

A 31-year-old woman was diagnosed with intestinal lymphoma (high-grade mucosa-associated lymphoid tissue lymphoma, stage IIE) in September 1996. Eleven courses of chemotherapy were administered, but the results were poor. She received autologous peripheral blood stem cell transplantation (PBSCT) in September 1997. Leukocytosis was noted, and chronic myelogenous leukemia was diagnosed 8 months after the PBSCT, progressing to blast phase 10 months later. We report this case because secondary chronic myelogenous leukemia after stem cell transplantation is rare.

Phosphorus removal characteristics of a combined AS-biofilm process cultured by different COD/TP ratios

The COD/TP ratio of influent is an important parameter for the phosphorus removal in a biological nutrient removal (BNR) process. In this study, we investigated the phosphorus removal and denitrification characteristics of a combined activated sludge-biofilm process, as cultured by different influent COD/TP ratios ranged from 12 to 120. Experimental results indicated that, when COD/TP ratios exceeded 30, the removal efficiencies of COD, TN and TP were 98%, 76% and 100%, respectively. However, when the COD/TP ratios were less than 30, the COD removal efficiency still surpassed 98%, but the TP removal efficiency decreased to 41% and 31.8% when COD/TP ratios were 20 and 12. Moreover, the weight percentage of phosphorus in the sludge attained a stable value when the COD/TP ratios were below 30. The maximum weight percentage of phosphorus in the sludge was found to be about 6% and, under this condition, the critical COD/TP ratio of influent was 30 of the process under a sludge retention time of 12 days. Although the amount of accumulated PHAs per mg phosphate released (gamma PHA/PO4) remained stable between a COD/TP ratio of 30 to 120, it increased with a decreased of the COD/TP ratio when the COD/TP ratio was less than 30.

The protein tyrosine kinase family of the human genome

As the sequencing of the human genome is completed by the Human Genome Project, the analysis of this rich source of information will illuminate many areas in medicine and biology. The protein tyrosine kinases are a large multigene family with particular relevance to many human diseases, including cancer. A search of the human genome for tyrosine kinase coding elements identified several novel genes and enabled the creation of a nonredundant catalog of tyrosine kinase genes. Ninety unique kinase genes can be identified in the human genome, along with five pseudogenes. Of the 90 tyrosine kinases, 58 are receptor type, distributed into 20 subfamilies. The 32 nonreceptor tyrosine kinases can be placed in 10 subfamilies. Additionally, mouse orthologs can be identified for nearly all the human tyrosine kinases. The completion of the human tyrosine kinase family tree provides a framework for further advances in biomedical science.

Lewis (FUT3) genotypes in Taiwanese, Thai, and Filipino populations

The Lewis (Le) blood type comprises two major antigens, Le(a) and Le(b), which are encoded by alpha (1,2)-fucosyltransferase (FUT2) and a (1,3/1,4)-fucosyl-transferase (FUT3). In this study, we analyzed the mutations of FUT3 in Taiwanese, Thai, and Filipino populations and correlated these with serologic phenotypes. One hundred and thirty-seven Taiwanese, 71 Thai, and 125 Filipino were studied unselectively. The frequency of the normal and four other mutant alleles for Taiwanese, Thai, and Filipino, respectively, were as follows: 187/274 (68.2%), 87/142 (61.3%), and 160/250 (64.0%) were wild type (Le); 14/274 (5.1%), 1/142 (0.7%), and 1/250 (0.4%) were a T202C/C314T mutation (le202,314); 35/274 (12.8%), 15/142 (10.6%), and 22/250 (8.8%) had the G508A mutation (le508); and 38/274 (13.9%), 39/142 (27.4%), and 67/250 (26.8%) carried the T1067A mutation (le1067). The le445 and le1007 were not detected in this study. Our result provided the first genetic data of the FUT3 gene in these three populations, and the frequency distribution of mutant alleles among Taiwanese, Thai, and Filipinos demonstrates a significant difference (P<0.001). In our study, the le202,314 mutation had considerable frequency in the Taiwanese, but the le1067 mutation had a higher frequency in Thai and Filipinos.

Molecular basis of Lewis blood type in Taiwanese

The Lewis (Le) histo-blood group system comprises two major antigens, Le(a) and Le(b) which are determined by alpha (1,2)-fucosyltransferase (FUT2) and alpha (1,3/1,4)-fucosyltransferase (FUT3). In this study, we analyzed the mutations of FUT2 and FUT3 genes in 101 Taiwanese by molecular biology method and compared them with their serologic phenotypes to explore their relationship. There is at least one wild allele of FUT2 and FUT3 genes in phenotype of Le (a-b+). The phenotypes of Le (a+b-) and Le (a+b+) are caused by mutations of both alleles of FUT2 gene and at least one wild allele of FUT3 gene. The genotypes of Le (a+b-) and Le (a+b+) are the same. Twenty cases are phenotype of Le (a-b-), which are caused by mutations of both alleles of FUT 2 gene and/or FUT 3 gene. Twelve cases were caused by both alleles mutations of FUT 3 gene only, while three cases were caused by mutations of both alleles of FUT2 gene and the rest of the cases were caused by mutations of both alleles of FUT2 and FUT3 genes. Our findings confirm that the Le histo-blood group is determined by the interaction of FUT 2 and FUT 3 genes. Our report is the first study of FUT 2 gene and FUT 3 gene in a Taiwanese population. We suggest that the genetic analysis of Le blood group should include FUT 2 and FUT 3 genes together.

Three-dimensional surface reconstruction and fluorescent visualization of cardiac activation

Optical imaging of transmembrane potentials in cardiac tissue is a rapidly growing technique in cardiac electrophysiology. Traditional studies typically use a monocular imaging setup, thus limiting investigation to a restricted region of tissue. However, studies of large-scale wavefront dynamics, especially those during fibrillation and defibrillation, would benefit from visualization of the entire epicardial surface. To solve this problem, a panoramic cardiac visualization algorithm was developed which performs the two tasks of reconstruction of the surface geometry of the heart, and representation of the panoramic fluorescence information as a texture mapping onto the geometry that was previously created. This system permits measurement of epicardial electrodynamics over a geometrically realistic representation of the actual heart being studied. To verify the accuracy of the algorithm, the procedure was applied to synthetic images of a patterned ball; further verification was provided by application of the algorithm to a model heart placed in the experimental setup. Both sets of images produced mean registration image errors on the order of 2 pixels, corresponding to roughly 3 mm on the geometry. We demonstrate the algorithm by visualizing epicardial wavefronts on an isolated, perfused rabbit heart.

Mechanisms of ventricular fibrillation induction by 60-Hz alternating current in isolated swine right ventricle

BACKGROUND

The mechanisms by which 60-Hz alternating current (AC) can induce ventricular fibrillation (VF) are unknown.

METHODS AND RESULTS

We studied 7 isolated perfused swine right ventricles in vitro. The action potential duration restitution curve was determined. Optical mapping techniques were used to determine the patterns of activation on the epicardium during 5-second 60-Hz AC stimulation (10 to 999 microA). AC captured the right ventricles at 100+/-65 microA, which is significantly lower than the direct current pacing threshold (0.77+/-0.45 mA, P:<0.05). AC induced ventricular tachycardia or VF at 477+/-266 microA, when the stimulated responses to AC had (1) short activation CLs (128+/-14 ms), (2) short diastolic intervals (16+/-9 ms), and (3) short diastolic intervals associated with a steep action potential duration restitution curve. Optical mapping studies showed that during rapid ventricular stimulation by AC, a wave front might encounter the refractory tail of an earlier wave front, resulting in the formation of a wave break and VF. Computer simulations reproduced these results.

CONCLUSIONS

AC at strengths less than the regular pacing threshold can capture the ventricle at fast rates. Accidental AC leak to the ventricles could precipitate VF and sudden death if AC results in a fast ventricular rate coupled with a steep restitution curve and a nonuniform recovery of excitability of the myocardium.

Safety and efficacy of cefpirome in comparison with ceftazidime in Chinese patients with sepsis due to bacterial infections

BACKGROUND

The safety and efficacy of cefpirome (CPM), a fourth-generation cephalosporin, has not yet been studied in an Asian population.

METHODS

Sixty-nine adult Chinese patients with sepsis due to bacterial infections were enrolled in the study and randomly assigned to receive CPM (2 g i.v. every 12 h) or ceftazidime (2 g i.v. every 8 h).

RESULTS

Both groups were comparable in terms of demographic, clinical and microbiological features. The causative pathogen was Escherichia coli or Klebsiella pneumoniae in the majority of microbiologically documented cases. The rates of clinical response (94 vs. 94%) and bacteriological response (65 vs. 68%) were similar in both groups. Similar adverse events, including rashes, gastrointestinal upset and asymptomatic elevation of hepatic enzymes, occurred in a minority of patients in both groups. All events were self-limited after discontinuation of the drugs.

CONCLUSION

CPM is as safe and effective as ceftazidime in the treatment of sepsis due to bacterial infections in Chinese patients.

Mutation analysis of PTEN/MMAC1 in acute myeloid leukemia

Recently, a putative tumor suppressor gene, PTEN/MMAC1, has been identified at chromosome 10q23.3, which encodes a 403 amino acid dual-specificity phosphatase containing a region of homology to tensin and auxillin. Somatic mutations of the PTEN/MMAC1 gene have been identified in a number of cancer cell lines and primary cancers. Mutations in PTEN/MMAC1 are most frequently found in advanced cancers. To evaluate the role of the PTEN/MMAC1 gene in leukemia, bone marrow and/or peripheral blood from 62 acute myeloid leukemia (AML) patients, 5 hemopoietic cell lines (HL60, U937, Raji, KG-1, K562), and 30 normal controls were analyzed. The results showed aberrant PTEN/MMAC1 transcripts in 15 of the 62 (24%) AML patients, 4 of the 5 cell lines (80%), and 4 of the 30 (13%) normal controls. As in our previous study of TSG101, the abnormal transcripts may result from aberrant RNA splicing as evidenced by the presence of both these aberrant transcripts and normal full length transcripts in all specimens examined. Loss of heterozygosity (LOH) analysis and PCR-SSCP of the entire coding region showed that none of the AML cases had LOH or mutation. Only one frameshift mutation at codon 130 (insertion of CCCG) with premature termination of coding sequence was observed in the U937 cell line. Our results indicate that the PTEN/MMAC1 gene may play a role in a small percentage of AML, but its significance needs to be further evaluated.

Dihydrofolate reductase from Kaposi's sarcoma-associated herpesvirus

Kaposi's sarcoma-associated herpesvirus (KSHV) is the first human virus known to encode dihydrofolate reductase (DHFR), an enzyme required for nucleotide and methionine biosynthesis. We have studied the purified KSHV-DHFR enzyme in vitro and analyzed its expression in cultured B-cell lines derived from primary effusion lymphoma (PEL), an AIDS-associated malignancy. The amino acid sequence of KSHV-DHFR is most similar to human DHFR (hDHFR), but the viral enzyme contains an additional 23 amino acids at the carboxyl-terminus. The viral DHFR, overexpressed and purified from E. coli, was catalytically active in vitro. The K(m) of KSHV-DHFR for dihydrofolate (FH(2)) was 2.4 microM, which is significantly higher than the K(m) of recombinant hDHFR (rhDHFR) for FH(2) (390 nM). K(m) values for NADPH were similar for the two enzymes, about 1 microM. KSHV-DHFR was inhibited by folate antagonists such as methotrexate (K(i): 200 pM), aminopterin (K(i): 610 pM), pyrimethamine (K(i): 29 nM), trimethoprim (K(i): 2.3 microM), and piritrexim (K(i): 3.9 nM). In all cases, K(i) values for these folate antagonists were higher for KSHV-DHFR than for rhDHFR. The viral enzyme was expressed at levels two- to tenfold higher than hDHFR in PEL cell lines as an early lytic cycle gene. KSHV-DHFR mRNA and protein appeared from 6 to 24 h after chemical induction of the KSHV lytic cycle. Epitope-tagged KSHV-DHFR and rhDHFR both localized to the nucleus of transfected cells, while other KSHV nucleotide metabolism genes localized to the cytoplasm. DHFR activity was not essential for viral replication in cultured PEL cells. Since hDHFR was not detectable in peripheral blood mononuclear cells (PBMCs), KSHV-DHFR may function to provide increased DHFR activity in vivo in infected cells that have little or none of their own enzyme.

[Analysis of imidacloprid and damanlin by high performance liquid chromatography]

A new method for determination of imidacloprid and damanlin by using HPLC was established. It was carried out on a mu Bondapak C18 column (3.9 mm i.d. x 300 mm) with ACN-MeOH-H2O (60:10:30, V/V) as eluent and detected at 240 nm using photodiode array detector. The results of imidacloprid and damanlin were 3.71% and 15.65% respectively. The standard deviations for imidacloprid and damanlin were 0.88% and 0.76% respectively.

Clinical implications of aberrant TSG101 transcripts in acute myeloblastic leukemia

Tsg101 is a mouse tumor suppressor gene whose homozygous deletion produces transformation of NIH3T3 cells and leads to metastases in nude mice. The human homologue of the gene, TSG101, is localized in chromosome 11p15.1-p15.2. Reduced TSG101 expression may cause the defect of the cell cycle checkpoint that leads to genetic instability and consequently to the progression of neoplasia. Aberrant TSG101 transcript have been identified in many types of cancers, and the relaxation of RNA splicing fidelity may be an onco-developmental marker in cancers and could play a general role in tumorigenesis. In our previous study, smaller TSG101 transcripts were found in AML specimens, hematopoietic cell lines and normal controls. The aberrant transcripts occurred more frequently in the AML cases and cell lines. The patients with aberrant TSG101 transcripts had higher initial white cell count, lower LDH level, and lower complete remission rate after induction chemotherapy. However, further multivariate analysis of clinical data revealed that there was no relationship to the TSG101 aberrant transcripts. The clinical significance of TSG101 aberrant transcript in AML needs further evaluation.

Mutation analysis of PTEN/MMAC 1 in sporadic thyroid tumors

Recently, a putative tumor suppressor gene, PTEN/MMAC1, has been identified at chromosome 10q23.3. This gene encodes a 403 amino acid dual specificity phosphatase containing a region of homology to tensin and auxillin. Somatic mutations of the PTEN/MMAC1 gene have been found in a number of cancer cell lines and primary cancers. Cowden disease, an autosomal dominant harmartoma syndrome associated with thyroid and breast tumors, has been found to be associated with mutations of PTEN/MMAC1 gene. To evaluate the role of the PTEN/MMAC1 gene in sporadic thyroid tumors, we studied 17 sporadic thyroid tumors, of which 12 were papillary thyroid carcinomas, 1 was follicular thyroid carcinoma, 1 was medullary thyroid carcinoma and 3 were thyroid adenomas. Direct sequencing of PCR-amplified products was performed for all nine exons of PTEN/MMAC1. No mutations of PTEN/MMAC1 gene were observed in any of the sporadic thyroid tumors. Our results indicate that the PTEN/MMAC1 gene may not play a major role in sporadic thyroid tumors.

Aberrant transcripts of FHIT, TSG101 and PTEN/MMAC1 genes in normal peripheral mononuclear cells

Aberrant transcripts of FHIT and TSG101 using nested RT-PCR were reported in many human tumours. The role of these aberrant transcripts in tumourigenesis is not clear. We, therefore, analyzed the aberrant transcripts of FHIT, TSG101 and PTEN/MMAC1 in peripheral mononuclear cells of normal individuals using nested RT-PCR to explore the role of these genes in cancer development. The results showed that there are at least five types of aberrant transcripts: type I is the deletion at junction located in-between normal exon and intron; type II has deletion of some bases and subsequent insertion of several bases in the deletion area; type III accommodates splicing donor or acceptor site-like sequence; type IV has homologous sequences near the deleted junction; and type V comprises the homologous sequences at the deletion junction. A normal healthy person can have more than one aberrant transcripts of FHIT, TSG101 and PTEN/MMAC1 genes. The size and the number of the transcripts vary and the diversity is unconstrained. It is not depended on the time, condition of the reaction, or the isolation method. From these results, we suggested that the aberrant transcripts of FHIT, TSG101 and PTEN/MMAC1 genes may be the imperfect products of splicesome which occur one in every thousands, ten thousands or more. As a result, these data implied no direct association between the aberrant transcripts and tumourigenesis.

Molecular characterization of secretor type alpha(1, 2)-fucosyltransferase gene deficiency in the Philippine population

We analyzed the seven mutations which are responsible for the deficiency of the secretor type alpha(1,2)-fucosyltransferase gene product, Se enzyme, in the Philippine population. One hundred and one unrelated Filipinos in Taiwan were studied. A new mutation, a 3-base pair deletion from nt 688 through 690, was found in two (0. 1%) of 202 chromosomes. The frequencies of six other mutated alleles were as follows: 71/202 (35.2%) were cDNA 385 A-->T missensed mutation (se2), 28/202 (13.9%) were C571T nonsense mutation (se3), 16/202 (7.9%) were G849A nonsense mutation (se4), 4/202 (1.9%) were G428A nonsense mutation (se1), and 81/202 (40.1%) were wild-type allele (Se). No C628T nonsense mutations (se5) or fusion genes of pseudogene and FUT2 gene (se 6) were found in this population. For the molecular basis of phenotype Le(a+ b-): eight cases had se2/se2, six cases had se2/se3, two cases had se3/se4, one case was homozygous of se4, one case was se3/se1, and two cases were se2/se7. For the Le(a+ b+) phenotype: four cases had se2/se2, two cases had se2/se3, one case was se3/se3, and one case was se2/se4. For the Le(a- b+) phenotype: 16 cases were Se/Se, 21 cases were Se/se2, six cases were Se/se3, five cases were Se/se4, and two cases had Se/se1. Our results suggest that the genotypes of the alpha(1, 2)-fucosyltransferase gene in phenotypes Le(a+ b+) and Le(a+ b-) are the same. Other factors that play important roles may cause the differences between these two phenotypes. Several hotspot mutations in the alpha(1,2)-fucosyltransferase gene are responsible for the nonsecretor phenotype.

MEQ and V-IL8: cellular genes in disguise?

One of the hallmarks of oncogenic viruses is their ability to subvert the growth regulation and evade immune response of the host. There are a number of tricks devised by various virus families. Oncogenic herpesviruses often accomplish this by encoding homologs of cellular genes involved in these functions. These viral homologs sometimes are hyperactive forms of their cellular counterparts, which function to overtake the cellular pathways, other times serve as decoys to mask the cellular functions. Marek's disease virus (MDV) carries at least two genes in that category. We have previously described Meq protein (MEQ gene product), a transcriptional factor with homology to proto-oncogenes Jun and Fos in the bZIP domain. Meq dimerizes with Jun or Fos and the Meq/Jun heterodimer is able to transactivate promoters with AP-1 site. We show here that Meq and Jun colocalize in living cells, adding to the physiological significance of the dimer formation. In addition, we present data to show that Meq and Jun can functionally complement each other in cis and in trans, using transformation and transactivation assays. Finally we describe the discovery of an IL8 chemokine homolog, designated as v-IL8 (viral IL8) in the MDV genome and discuss its possible function in MDV infection.