[Characteristics of serum bile acids among healthy children in Zhejiang province]

Objective: To characterize the serum bile acid profiles of healthy children in Zhejiang Province. Methods: A cross-sectional study was conducted on 245 healthy children who underwent imaging and laboratory biochemical tests during routine physical examinations at the Children's Hospital of Zhejiang University School of Medicine from January 2020 to July 2022. Overnight fasting venous blood samples were collected, and the concentrations of 18 individual bile acids in the serum were accurately quantitated using tandem mass spectrometry. The concentration difference of bile acid were compared between different genders and to explore the correlation between age and bile acid levels. Used the Mann-Whitney U test for intergroup comparison and Spearman test to correlation analysis. Results: A total of 245 health children with a age of 10 (8, 12) years including 125 boys and 120 girls. There were no significant differences in levels of total bile acids, primary and secondary bile acids, free and conjugated bile acids between the two gender groups (all P>0.05). The serum concentrations of ursodeoxycholic acid and glycoursodeoxycholic acid in girls were significantly higher than those in boys (199.0 (66.9, 276.5) vs. 154.7 (49.3, 205.0) nmol/L, 274.0 (64.8, 308.0) vs. 181.0 (43.8, 209.3) nmol/L, Z=2.06, 2.71, both P<0.05). The serum taurolithocholic acid in both boys and girls were positively correlated with age (r=0.31, 0.32, both P<0.05). The serum chenodeoxycholic acid and glycochenodeoxycholic acid in the boys group were positively correlated with age (r=0.20, 0.23, both P<0.05), whereas the serum tauroursodeoxycholic acid in the girls group was negatively correlated with age (r=-0.27, P<0.05), and the serum cholic acid was positively correlated with age (r=0.34, P<0.05). Conclusions: The total bile acid levels are relatively stable in healthy children in Zhejiang province. However, individual bile acids showed gender differences and were correlated with age.

Continuous positive airway pressure for treating hypoxemia due to pulmonary vein injury: A case report

BACKGROUND

Vascular injury during thoracoscopic surgery for esophageal cancer is a rare but life-threatening complication that can lead to severe hypotension and hypoxemia. Anesthesiologists need to provide rapid and effective treatment to save patients' lives.

CASE SUMMARY

A 54-year-old male patient was scheduled to undergo a thoracoscopic-assisted radical resection of esophageal cancer through the upper abdomen and right chest. While dissociating the esophagus from the carina through the right chest, unexpected profuse bleeding occurred from a suspected pulmonary vascular hemorrhage. While the surgeon attempted to achieve hemostasis, the patient developed severe hypoxemia. The anesthesiologist implemented continuous positive airway pressure (CPAP) using a bronchial blocker (BB), which effectively improved the patient’s oxygenation and the operation was completed successfully.

CONCLUSION

CPAP using a BB can resolve severe hypoxemia caused by accidental injury of the left inferior pulmonary vein during surgery.

[A clinical challenge of evaluation and management in children with genetic obesity]

Obesity is a growing global public health problem, while 40%-70% of obesity is determined by genetic factors. This article focuses on the classification, disease characteristics, diagnosis and progressive treatment of childhood genetic obesity. The prevention and control of childhood genetic obesity requires early detection of obese individuals and early screening of obesity causes. At the same time, clinicians are advised to propose individualized therapy and intervention measures based on multi-disciplinary opinions to improve the health of genetic obese children.

[Analysis of clinical phenotype and genotype of Chinese children with disorders of sex development]

Objective: To explore the heterogeneity and correlation of clinical phenotypes and genotypes in children with disorders of sex development (DSD). Methods: A retrospective study of 1 235 patients with clinically proposed DSD in 36 pediatric medical institutions across the country from January 2017 to May 2021. After capturing 277 DSD-related candidate genes, second-generation sequencing was performed to analyzed the heterogeneity and correlation combined with clinical phenotypes. Results: Among 1 235 children with clinically proposed DSD, 980 were males and 255 were females of social gender at the time of initial diagnosis with the age ranged from 1 day of age to 17.92 years. A total of 443 children with pathogenic variants were detected through molecular genetic studies, with a positive detection rate of 35.9%. The most common clinical phenotypes were micropenis (455 cases), hypospadias (321 cases), and cryptorchidism (172 cases) and common mutations detected were in SRD5A2 gene (80 cases), AR gene (53 cases) and CYP21A2 gene (44 cases). Among them, the SRD5A2 mutation is the most common in children with simple micropenis and simple hypospadias, while the AMH mutation is the most common in children with simple cryptorchidism. Conclusions: The SRD5A2 mutation is the most common genetic variant in Chinese children with DSD, and micropenis, cryptorchidism, and hypospadias are the most common clinical phenotypes. Molecular diagnosis can provide clues about the biological basis of DSD, and can also guide clinicians to perform specific clinical examinations. Target sequence capture probes and next-generation sequencing technology can provide effective and economical genetic diagnosis for children with DSD.

[Relationship between body mass index and sexual development in Chinese children]

Objective: To investigate the relationship between body mass index (BMI) and sexual development in Chinese children. Methods: A nationwide multicenter and population-based large cross-sectional study was conducted in 13 provinces, autonomous regions and municipalities of China from January 2017 to December 2018. Data on sex, age, height, weight were collected, BMI was calculated and sexual characteristics were analyzed. The subjects were divided into four groups based on age, including ages 3-<6 years, 6-<10 years, 10-<15 years and 15-<18 years. Multiple Logistic regression models were used for evaluating the associations of BMI with sexual development in children. Dichotomous Logistic regression was used to compare the differences in the distribution of early and non-early puberty among normal weight, overweight and obese groups. Curves were drawn to analyze the relationship between the percentage of early puberty and BMI distribution in girls and boys at different Tanner stages. Results: A total of 208 179 healthy children (96 471 girls and 111 708 boys) were enrolled in this study. The OR values of B2, B3 and B4+ in overweight girls were 1.72 (95%CI: 1.56-1.89), 3.19 (95%CI: 2.86-3.57), 7.14 (95%CI: 6.33-8.05) and in obese girls were 2.05 (95%CI: 1.88-2.24), 4.98 (95%CI: 4.49-5.53), 11.21 (95%CI: 9.98-12.59), respectively; while the OR values of G2, G3, G4+ in overweight boys were 1.27 (95%CI: 1.17-1.38), 1.52 (95%CI: 1.36-1.70), 1.88 (95%CI: 1.66-2.14) and in obese boys were 1.27 (95%CI: 1.17-1.37), 1.59 (95%CI: 1.43-1.78), and 1.93 (95%CI: 1.70-2.18) (compared with normal weight Tanner 1 group,all P<0.01). Analysis in different age groups found that OR values of obese girls at B2 stage and boys at G2 stage were 2.02 (95%CI: 1.06-3.86) and 2.32 (95%CI:1.05-5.12) in preschool children aged 3-<6 years, respectively (both P<0.05). And in the age group of 6-10 years, overweight girls had a 5.45-fold risk and obese girls had a 12.54-fold risk of B3 stage compared to girls with normal BMI. Compared with normal weight children, the risk of early puberty was 2.67 times higher in overweight girls, 3.63 times higher in obese girls, and 1.22 times higher in overweight boys, 1.35 times higher in obese boys (all P<0.01). Among the children at each Tanner stages, the percentage of early puberty increased with the increase of BMI, from 5.7% (80/1 397), 16.1% (48/299), 13.8% (27/195) to 25.7% (198/769), 65.1% (209/321), 65.4% (157/240) in girls aged 8-<9, 10-<11 and 11-<12 years, and 6.6% (34/513), 18.7% (51/273), 21.6% (57/264) to 13.3% (96/722), 46.4% (140/302), 47.5% (105/221) in boys aged 9-<10, 12-<13 and 13-<14 years, respectively. Conclusions: BMI is positively correlated with sexual development in both Chinese boys and girls, and the correlation is stronger in girls. Obesity is a risk factor for precocious puberty in preschool children aged 3-<6 years, and 6-<10 years of age is a high risk period for early development in obese girls.

[The construction of comprehensive stroke prevention and control system requires attention to the precise policies of young stroke]

Youth is the core force of social and economic development, once the occurrence of youth stroke will place a heavy burden on society and family. However, the prevention and control of stroke in China is mainly aimed at middle-aged and elderly patients, the part of young stroke is relatively easy to be ignored. This article focuses on the characteristics, research progress, prevention and control status of young stroke, pointing out the importance of centering on the prevention and treatment of young stroke. At the same time, it hopes that the industry can concentrate on the prevention and treatment of young stroke, making precise policies in the future, and developing secondary prevention guidelines for the causes or risk factors of young stroke, so as to improve comprehensive stroke prevention and control system. On this basis, the health level of the whole population will be improved, and the life expectancy of residents will be extended, thus promoting the realization of the strategic goal of "Healthy China 2030".

[Changing prevalence of overweight and obesity among Chinese children aged 6-15 from 2009-2019]

Objective: To analyze the trends of overweight and obesity prevalence in Chinese children, aged from 6 to 15 years old among 4 provinces and cities from 2009 to 2019. Methods: Reviewed the national multi-center epidemiological survey data of children from the National Key Technology R&D Program of China during the Eleventh Five-Year Plan (2009 to 2010) and the National Key Research and Development Program of China during the Thirteenth Five-Year Plan (2017 to 2019). The participants' data were selected from four provinces,municipalities and autonomous region,including Beijing, Tianjin (Northern region), Zhejiang (Eastern region), and Guangxi (Southern region). Totally 14 597 pairs of 6-15 year-old children were surveyed. According to the body mass index (BMI) and standard deviation score (SDS) of children among different genders, ages, and regions, t test or chi-square test was used to evaluate the changes in overweight and obesity over a 10-year span. Results: Totally 7 721 pairs of boys and 6 876 pairs of girls were collectted in this study, whose mean age was (10.7±2.5) years. In the past 10 years, the overall BMISDS were 0.39±1.24 and 0.36±1.31 and the overall obesity rate were 11.8% (n=1 773) anel 12.5% (n=1 813) of children in the 4 administrative regions did not have statistically significant differences (all P>0.05). However, the overall overweight rate rose from 17.1% (n=2 496) to 19.1% (n=2 781) (χ²=18.657, P<0.01), and the average annual growth rate was 0.20%. The BMISDS in the Eastern region increased from 0.10±1.07 to 0.19±1.22 (t=-4.095, P<0.01), and the overweight rate and obesity rate increased by 3.8% (n=202) and 3.1% (n=169) respectively (both P<0.01); the BMISDS in the Northern region and the obesity rate did not have statistically significant differences(all P>0.05), but the overweight rate rose from 20.5% (n=1 233) to 22.8% (n=1 365) significantly (χ²=7.431, P<0.01); BMISDS in the Southern region was significantly decreased from 0.30±1.19 to 0.09±1.25 (t=1.426, P<0.01), and the rate of obesity decreased from 9.8% (n=315) to7.9% (n=256) (χ²=6.46, P<0.05), the overweight rate was not stafistically significant (P=0.10), respectively. The obesity rate of boys had risen from 16.4% (n=1 265) to 18.2% (1 407) (χ²=8.997, P<0.01) in the past 10 years, and the overweight rate had risen from 18.0% (n=1 393) to 20.5% (n=1 579) (χ²=14.26, P<0.01). The overweight+obesity rate rose from 34.4% (n=2 658) to 38.7% (n=2 986) (χ²=29.859, P<0.01), and the weight problem in the age group of 8 to 11 years was particularly severe (all P<0.01). The obesity rate of girls dropped from 6.8% (n=468) to 5.9% (n=406) (χ²=4.546, P<0.05), the overweight rate rose from 16.0% (n=1 103) to 17.5% (n=1 202) (χ²=5.006, P<0.05), and the overall overweight+obesity rate rose from 22.8% (n=1 571) to 23.4% (n=1 608) (χ²=0.53, P>0.05). Conclusions: The growth rate of obesity among children in China had slowed down from 2009 to 2019, but the overweight rate was still on the rise. The overall base of overweight and obesity population continued to expand. The weight problem of peri-adolescent boys was particularly prominent. The current status of obesity epidemics in different regions, ages, and genders are significantly different and had their own characteristics. It is necessary to establish a personalized prevention and control strategy.

Ginkgolide B Maintains Calcium Homeostasis in Hypoxic Hippocampal Neurons by Inhibiting Calcium Influx and Intracellular Calcium Release

Ginkgolide B (GB), a terpene lactone and active ingredient of Ginkgo biloba, shows protective effects in neuronal cells subjected to hypoxia. We investigated whether GB might protect neurons from hypoxic injury through regulation of neuronal Ca²⁺ homeostasis. Primary hippocampal neurons subjected to chemical hypoxia (0.7 mM CoCl₂) in vitro exhibited an increase in cytoplasmic Ca²⁺ (measured from the fluorescence of fluo-4), but this effect was significantly diminished by pre-treatment with 0.4 mM GB. Electrophysiological recordings from the brain slices of rats exposed to hypoxia in vivo revealed increases in spontaneous discharge frequency, action potential frequency and calcium current magnitude, and all these effects of hypoxia were suppressed by pre-treatment with 12 mg/kg GB. Western blot analysis demonstrated that hypoxia was associated with enhanced mRNA and protein expressions of Ca_v1.2 (a voltage-gated Ca²⁺ channel), STIM1 (a regulator of store-operated Ca²⁺ entry) and RyR2 (isoforms of Ryanodine Receptor which mediates sarcoplasmic reticulum Ca²⁺ release), and these actions of hypoxia were suppressed by GB. Taken together, our in vitro and in vivo data suggest that GB might protect neurons from hypoxia, in part, by regulating Ca²⁺ influx and intracellular Ca²⁺ release to maintain Ca²⁺ homeostasis.

[Preliminary investigation of gender assignment in 46,XY disorders of sex development with severe male undermasculinisation]

Objective: To explore the feasibility of gender assignment in 46,XY disorders of sex development (DSD) with severe undermasculinisation mainly based on molecular diagnosis. Methods: A retrospective study of 45 patients of 46, XY DSD with severe undermasculinisation were admitted between November 2015 and October 2018 at Children's Hospital, Zhejiang University School of Medicine. The initial social gender were all female, of whom the external genital manifestations were Prader 0 to 2; the degree of masculinity was scored using external masculinisation score (EMS); the position and development of the gonads were examined by ultrasound, cystoscopy and laparoscopy, also including assessing the development of the Wolffian tube and the Müllerian tube. The level and ratio of testosterone to dihydrotestosterone before and after hCG stimulation were evaluated for the function of Leydig cell and 5α-reductase-2. Gender role scales and sandbox games were used to assess gender role behavior. Genital sensitivity to androgen stimulation was assessed; A panel including 163 genes related to gender development were determined by second-generation sequencing in all 45 patients. Finally, a multidisciplinary team (MDT) makes a gender assignment after a comprehensive analysis mainly based on the molecular etiological diagnosis. Results: Thirty-nine out of 45 patients (87%) had an identifiable genetic etiology, and the remaining 6 (13%) were negative for genetic testing. Forty-five patients had EMS less than or equal to 3 points. Sexual psychological assessment was performed in 39 patients, with male dominance in 24 (62%) and female dominance in 15 (38%). The gender assignment was 23 cases (51%) for male and 19 cases (42%) for female, and 3 cases (7%) were not completely determined. Conclusions: Molecular diagnosis provides a strong basis for appropriate gender assignment of 46, XY DSD children with severe undermasculinisation. Based on molecular diagnosis, each DSD should be analyzed by professional MDT to analyze the clinical symptoms/signs, gonadal development, gonad tumor risk, external genital morphology, sexual psychological assessment, potential fertility opportunities, parental views, Social and cultural factors, etc. make appropriate gender assignment.

[Hyperglycemia caused by mutation of GCK gene in 10 patients analysis of clinical and mutation characteristics]

Objective: To explore the gene mutation characteristics and detailed clinical presentations of hyperglycemia caused by GCK mutations in 10 patients. Methods: The clinical and follow-up data of 10 patients with hyperglycemia caused by mutation of GCK gene were reviewed. The patients were ascertained between January 1, 2014 and August 31, 2018 at the Department of Pediatrics, the First Affiliated Hospital of Zhejiang University and Ningbo Women & Children's Hospital. Clinical data were collected, including age, gender, main complaint, family history, fasting blood glucose, fasting blood insulin, 2-hour blood glucose, 2-hour blood insulin after oral glucose tolerance test, glycosylated hemoglobin, anti-glutamic acid decarboxylase antibody and body mass index. Mutations of GCK gene were detected by Sanger sequencing or high-throughput sequencing of diabetes-related genes in the patients and their family members. Results: There were ten patients, 8 of them were male, 2 were female.The ages at diagnosis varied between 4.7 to 12.3 years. The patients usually did not have obvious clinical symptoms of diabetes mellitus. Most of them were unexpectedly found to have hyperglycemia and with impaired glucose metabolism in three consecutive generations. The fasting blood glucose of patients was 6.8-7.7 mmol/L, 2-hour postprandial blood glucose was 7.8-11.6 mmol/L. Fasting blood insulin was 0.5-8.5 mU/L, glucose tolerance test results showed that 2 h postprondial blood insulin was 1.3-55.4 mU/L. The level of glycosylated hemoglobin was 6.1%-6.8%. Anti-glutamic acid decarboxylase antibody was negative in all patients. The GCK mutations identified in patients and one of their parents were located at exon5 (4 cases), exon9 (2 cases), exon2 (1 case), exon4 (1 case), exon6 (1 case) and exon7 (1 case). Conclusions: Most of the hyperglycemia patients caused by GCK mutations did not have typical clinical symptoms of diabetes. The fasting blood glucose was slightly elevated. Abnormal glucose tolerance test results were found in all 10 patients. Three consecutive generations of family had impaired glucose metabolism. GCK mutations located at exon 5 were common in 10 cases. There was no correlation between type of mutations and plasma glucose levels in domestic and international researches. When fasting glucose was found abnormal in clinic, a complete family history should be taken and the GCK gene should be sequenced to confirm the diagnosis in time.

[Advances in the research of pressure therapy for pediatric burn patients with facial scar]

Facial scar and deformation caused by burn injury severely affect physical and psychological well-being of pediatric burn patients, which needs medical workers and pediatric burn patients' family members to pay much attention to and to perform early rehabilitation treatment. Pressure therapy is an important rehabilitative strategy for pediatric burn patients with facial scar, mainly including wearing headgears and transparent pressure facemasks, which have their own features. To achieve better treatment results, pressure therapy should be chosen according to specific condition of pediatric burn patients and combined with other assistant therapies. Successful rehabilitation for pediatric burn patients relies on cooperation of both family members of pediatric burn patients and society. Rehabilitation knowledge should be provided to parents of pediatric burn patients to acquire their full support and cooperation in order to achieve best therapeutic effects and ultimately to rebuild physical and psychological well-being of pediatric burn patients.

[Effect of calcium-independent phospholipase A(2) inhibitor in reducing hepatocyte lipoapoptosis and improving insulin resistance]

Objective: To investigate the effect of calcium-independent phospholipase A(2) (iPLA(2)) inhibitor in reducing hepatocyte lipoapoptosis and improving insulin resistance. Methods: A total of 28 male Sprague-Dawley rats were randomly divided into the following three groups: 12 rats in group I (normal control group) were given normal diet for 18 weeks; 8 rats in group II (non-alcoholic fatty liver disease model group) were given high-fat diet for 18 weeks; 8 rats in group III (iPLA(2) inhibitor group) were given high-fat diet for 18 weeks and intraperitoneal injection of the iPLA(2) inhibitor bromoenol lactone 150 μg/kg once every other day since week 15 (14 times of injection in total). All the rats were sacrificed at the same time, and body weight and liver weight were measured. Blood lipids, serum enzymes, fasting blood glucose, fasting insulin, free fatty acid, and serum iPLA(2) concentration were measured in each group, and liver pathological changes were evaluated. The terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling was used to measure the level of hepatocyte apoptosis and the apoptotic index was calculated. Quantitative PCR was used to measure the mRNA expression of iPLA(2). The Student-Newman-Keuls test and the chi-square test were used for comparison of parameters between groups I, II, and III. P < 0.05 was considered statistically significant. Results: Compared with group I, group II had significant increases in triglyceride (0.75±0.05 mmol/L vs 1.20±0.13 mmol/L, P < 0.05), cholesterol (1.50±0.12 mmol/L vs 2.94±0.34 mmol/L, P < 0.05), low-density lipoprotein (0.65±0.06 mmol/L vs 1.30±0.16 mmol/L, P < 0.05), free fatty acid (0.58±0.09 mEq/L vs 0.80±0.20 mEq/L, P < 0.05), fasting blood glucose (4.85±0.22 mmol/L vs 6.94±0.65 mmol/L, P < 0.05), and fasting insulin (0.89±0.52 mmol/L vs 1.29±0.52 mmol/L, P < 0.05), and a significant reduction in the insulin sensitivity index (0.52±0.21 vs 0.27±0.11, P < 0.05); group II also had significant inflammation and fatty degeneration shown by liver pathology, and compared with group I, group II had significant increases in apoptotic cells and apoptotic index (0.58%±0.17% vs 39.69%±4.96%, P < 0.05). Compared with group I, group II had significant increases in serum iPLA(2) concentration (2.92±0.08 ng/ml vs 3.28±0.14 ng/ml, P < 0.05) and the mRNA expression of iPLA(2) in the liver (1.07±0.18 vs 7.68±0.49, P < 0.05). Compared with group II, group III had a lower level of hepatocyte apoptosis, a significant reduction in apoptotic index (39.69%±4.96% vs 24.80%±2.53%, P < 0.05), significant reductions in serum iPLA(2) concentration (3.28±0.14 ng/ml vs 2.64±0.24 ng/ml, P < 0.05) and the mRNA expression of iPLA(2) in the liver (7.68±0.49 vs 2.60±0.36, P < 0.05), significant reductions in fasting insulin (1.29±0.52 mmol/L vs 0.80±0.09 mmol/L, P < 0.05) and fasting blood glucose (6.94±0.65 mmol/L vs 5.18±0.35 mmol/L, P < 0.05), and a significant increase in insulin sensitivity index (0.27±0.11 vs 0.45±0.09, P < 0.05). Conclusion: There is a significant increase in the expression of iPLA(2) in rats with non-alcoholic fatty liver disease, and iPLA2 inhibitor can reduce hepatocyte lipoapoptosis and improve insulin resistance.

First Report of Anthracnose of Malva sylvestris Caused by Colletotrichum trifolii in China

Common mallow (Malva sylvestris L.) is a perennial medicinal plant in the Malvaceae family, which is native to Asia, Europe, and North Africa. In July 2012, typical symptoms of anthracnose disease, with a disease incidence of ~70%, were observed on common mallow in the Medicinal Herb Garden of Shenyang Pharmaceutical University, Liaoning, China. The fungus mainly infected the stalks and leaves of M. sylvestris. Pinpoint, brownish lesions initially appeared at the flowering stage and the disease spread within the field. The lesions on stems gradually enlarged and became dark brown, elliptical, and slightly concave. Concurrently, acervuli and mucilaginous conidial masses of the pathogen appeared on lesions under moist conditions. Conidia were hyaline, one-celled, cylindrical with both ends rounded, and measured 10.0 to 12.5 × 2.5 to 4.0 μm (mean 11.3 × 3.3 μm). The fungus was isolated from symptomatic tissues. Small pieces from leaves and stems were surface disinfested with 70% ethanol and 1.5% sodium hypochlorite for 1 min, then rinsed three times with sterile distilled water, and cultured on potato dextrose agar (PDA) at 25°C. The colonies on PDA had initially white aerial mycelia, and later became greenish black with regularly whorled rings. To confirm Koch's postulates, five 3-month-old plants of M. sylvestris were inoculated with a conidial suspension (10⁵ conidia/ml) prepared from PDA cultures incubated for 14 days. Five non-inoculated plants served as controls. The plants were maintained in the greenhouse at 22 to 25°C and about 75% relative humidity under natural daylight. Typical symptoms on inoculated plants were reproduced after ~10 to 14 days, whereas control plants remained asymptomatic. The pathogen was successfully recovered from symptomatic tissues and re-identified, completing Koch's postulates. The internal transcribed spacer (ITS) and large subunit -28S (LSU) region of rDNA was amplified with primers ITS1/ITS4 and NL1/NL4, respectively, and sequenced. Phylogenetic trees (ITS and LSU) that were obtained using MEGE3.1 with the neighbor-joining method showed that both of the isolates fall in the Colletotrichum trifolii clade. The representative sequences (ITS and LSU) were deposited in GenBank (Accession Nos. KJ155692 and KJ920935). The fungus isolated from symptomatic tissues was identified as C. trifolii on the basis of morphological, cultural characteristics, and sequence analysis (2). According to previous references, C. orbiculare and C. malvarum on Malvaceae were respectively described in America and Europe (1,3,4). However, the isolate from M. sylvestris significantly differed from those of C. orbiculare and C. malvarum in cultural characteristics and sequence analysis. In this paper, the results showed that M. sylvestris is a new host of C. trifolii. To our knowledge, this is the first report of mallow anthracnose caused by C. trifolii in China. References: (1) J. A. Bailey et al. Phytopathology 86:1076, 1996. (2) U. Damm et al. Fungal Divers. 61:29, 2013. (3) K. Hyde et al. Fungal Divers. 39:147, 2009. (4) L. Tosi et al. Plant Dis. 88:425, 2004.

First Report of Root Rot on Pulsatilla koreana Caused by Fusarium oxysporum in China

Windflowers (Pulsatilla spp.) are perennial medicinal plants in the family Ranunculaceae with high economic as well as medicinal value in China. It is commonly used as traditional Chinese medicine (1). In May 2012, a root rot disease was observed on windflower (Pulsatilla koreana Nakai) at flowering stages in fields of Liaoning Province, China. The diseased area was estimated to be over 500 ha in the province and the yield was reduced by 30% on average with up to 45% yield losses in some fields. As the disease progressed, brown lesion production extended onto lateral and main roots, and aboveground tissues shriveled and decayed; in severe cases, white mycelium was clearly visible on diseased root tissue. Isolations from symptomatic roots were made on potato dextrose agar (PDA) and single-spore cultures were obtained. Colonies were initially white, but became pale violet with age, and purple pigments were produced in the agar. Microconidia were abundant, unicellular, oval to reniform, and ranged from 5.6 to 13.1 (9.3) × 2.8 to 4.2 (3.2) μm. Macroconidia were sparse, three-septate, slightly curved, and ranged from 21.9 to 39.4 (31.2) × 3.4 to 4.5 (3.9) μm. The isolated fungus was morphologically similar to Fusarium oxysporum (2). Two isolates were selected for molecular identification, and the internal transcribed spacer (ITS) region of rDNA was amplified using the primers ITS1/ITS4 (3) and sequenced. The obtained sequences (GenBank Accession Nos. JX669525 and JX669526) showed 99% homology with the sequences of F. oxysporum in GenBank (GQ121303). For pathogenicity tests, the isolate was cultured on PDA for 10 days at 25°C. Inoculations were performed on 10 healthy P. koreana plants by spraying a conidial suspension (2.0 × 10⁵ microconidia ml^-1) on roots previously wounded with a metal needle. Ten non-treated plants used as controls were sprayed with distilled water. The inoculated plants were incubated at 25°C under conditions of 12/12 h (light and dark). After 2 weeks, root rot symptoms were similar to the original symptoms observed under field conditions. No disease was observed on water-inoculated control plants. The same fungus was reisolated from the roots of infected plants, satisfying Koch's postulates. To our knowledge, this is the first report of F. oxysporum on P. koreana in China. The disease was hitherto scarcely reported in any other countries, and may deserve more attention in the future. References: (1) S. C. Bang et al. J. Nat. Prod. 68:268, 2005. (2) J. F. Leslie and B. A. Summerell. The Fusarium Laboratory Manual. Blackwell Professional, Ames, IA, 2006. (3) T. J. White et al. Page 315 in: PCR Protocols: A Guide to Methods and Applications. Academic Press, San Diego, 1990.

First Report of Sclerotinia Rot of Chinese Atractylodes Caused by Sclerotinia nivalis in China

Chinese atractylodes (Atractylodes japonica Koidz.ez Kitam.) is a perennial herb in the Compositae family, and is widely distributed in China. The dried rhizomes of the plant are used in traditional Chinese medicine. During the summer of 2011, typical signs and symptoms of Sclerotinia rot were observed on Chinese atractylodes in a production field of Liaoning Province of China. Symptoms were observed in plants at the flowering stage, distributed in patches throughout the rows, and with a disease incidence of approximately 10 to 15%. The lower mature leaves of infected plants first became yellow and wilted, basal stem areas showed a black-brown rot at the same time under conditions of high humidity, and white cottony mycelium formed along the basal stem and soil surfaces. Ultimately, the basal stem and roots rotted and the plants wilted and died quickly. Black, irregular sclerotia (average 0.8 to 6.9 mm in diameter) were also observed within the pith cavity of split stems and rotted roots. The pathogen was isolated from symptomatic tissues and sclerotia, surface disinfested with 2% sodium hypochlorite, and cultured on potato dextrose agar (PDA) (1). The fungus was mesophilic, with an optimum temperature for mycelial growth in culture of about 20°C. Colonies on PDA produced masses of white aerial mycelium, with small white flocci distributed among sclerotia. After 2 weeks, sclerotia 0.5 to 4.5 mm in diameter were produced near the margin in a uniform distribution. Sclerotia were spherical, elongated, or fused to form irregular shapes and tightly attached to the agar surface by their under surface, which could be seen through the bottom of the petri dishes. DNA sequences of five replicates were obtained using the TianGen DNA secure plant kit. The internal transcribed spacer (ITS) region of rDNA was amplified with primers ITS1/ITS4 and sequenced. BLAST analysis of the 513-bp segment showed high similarity (99%) with a sequence of Sclerotinia nivalis (GenBank Accession No. AB516670). A representative sequence was deposited in GenBank (Accession No. JX294862). The fungus isolated from symptomatic tissues was identified as S. nivalis Saito on the basis of morphological and cultural characteristics (2,3) and ITS sequence analysis. Symptoms were reproduced in the greenhouse by inoculating the basal stem and roots of 15 atractylodes plants at the 7- to 10-leaf stage. Inoculum was prepared by macerating 14-day-old PDA cultures of the fungus in a blender and placing the mixture (approximately 20 g) into the potting medium of each plant. Sterile PDA was used to inoculate the five control plants. Plants were maintained in a greenhouse at 22 to 25°C and about 75% relative humidity. After 7 to 10 days, symptoms were similar to those in the fields. Lower leaves of inoculated plants became yellow and wilted, and infected plants died 2 weeks after inoculation, whereas control plants remained healthy. The pathogen was successfully recovered from symptomatic tissues, completing Koch's postulates. To our knowledge, this is the first report of Sclerotinia rot of Chinese atractylodes. Given its wide host range, S. nivalis has great potential to become an economically important plant pathogen. References: (1) W. G. Kim and W. D. Cho. Mycobiology 30:41, 2002. (2) G. Q. Li et al. Mycol. Res. 104:232, 2000. (3) I. Saito. Mycoscience 38:227, 1997.

Sclerotinia Rot of Windflower (Pulsatilla koreana Nakai) Caused by Sclerotinia nivalis in China

Windflowers (Pulsatilla spp.) are perennial medicinal plants in the family Ranunculaceae with high economic as well as medicinal value in China. It is a commonly used traditional Chinese medicine (1). In 2012, a stem rot disease was observed on windflower (P. koreana Nakai) at flowering stages in fields of Liaoning Province, China. Disease incidence ranged from 10 to 65% (average of 45%) and resulted in approximately 25 to 60% yield loss. The infected area of plants initially takes on a dark green or brown water-soaked appearance and then becomes paler. Soon after, plants turn brown or black and die. If moisture conditions remain conducive, a cottony mycelium cover was observed on the affected area. Later, the mycelium usually produces numerous black sclerotia that were up to 1 cm long in affected plant parts. Diseased tissue were surface sterilized for 1 min in 1% NaOCl (v/v), rinsed with sterilized distilled water, and plated on potato dextrose agar (PDA). Isolates were mesophilic, with an optimum growth temperature of around 20°C. Colonies on PDA were white, with abundant aerial mycelium. Some mycelium in the colony center, especially that submerged in the medium, was light brown. Sclerotia were spherical to subspherical, elongated or fused to form irregular shapes, 2.5 to 9.0 × 2.0 to 6.8 mm. They were tightly attached to the agar surface by their under surface, which could be seen through the bottom of the petri dishes. These characteristics were consistent with Sclerotinia nivalis (2,3). Two isolates were selected for molecular identification. The internal transcribed spacer (ITS) region of rDNA was amplified using the primers ITS1/ITS4 (4) and sequenced. The obtained sequences (GenBank Accession Nos. JX206828 and JX424615) showed 99 and 100% homology with the sequences of S. nivalis in GenBank (Accession No. AB516670). To demonstrate pathogenicity, mycelial blocks of the isolates grown on PDA were placed on the base of the stems of ten 1-month-old Pulsatilla koreana plants. The same numbers of control plants were treated with PDA plugs as a control. The inoculated plants were incubated at 25°C with a 12-h photoperiod. After 4 days, the initiation of stem necrosis was observed, and 9 days after inoculation, the plants collapsed and died. Control plants had no symptoms. The same fungus was reisolated from all inoculated plants, satisfying Koch's postulates. To our knowledge, this is the first confirmed report of windflower as a natural host for S. nivalis in China. References: (1) S. C. Bang et al. J. Nat. Prod. 68:268, 2005. (2) G. Q. Li et al. Mycol. Res. 104:232, 2000. (3) I. Saito. Mycoscience. 38:227, 1997. (4) T. J. White et al. Page 315 in: PCR Protocols: A Guide to Methods and Applications. Academic Press, San Diego, 1990.

Severe Outbreak of Rust Caused by Coleosporium pulsatillae Detected on Pulsatilla spp. in China

Windflower (Pulsatilla spp.) is a perennial medicinal plant in the Ranunculaceae with high economic value as well as medicinal value in China. It is a commonly used Chinese herbal medicine. In 2007, two species, Pulsatilla koreana Nakai and P. chinensis Regel, were observed with severe rust symptoms at three locations (Shenyang City, Benxi City, and Fushun County) in Liaoning, China. The diseased area was estimated to be more than 500 ha and the yield was reduced by 30% on average with up to 65% yield losses in some fields. Since its first record in 2007, the disease has been recorded every year in parts of China. A survey of all cultivated fields in August 2011 revealed that 90% of the Pulsatilla plants were heavily infected with rust. Early symptoms on the adaxial leaf surfaces were small, circular, yellow spots that later enlarged, coalesced, and developed necrotic centers. On the abaxial side, numerous yellow rust uredinia were visible. Urediniospores are globose or ellipsoidal, sometimes angular in shape, with a yellowish content, and measured 22.6 to 39.4 × 15.2 to 23.9 μm. Spore walls were coarsely verrucose when examined by light and scanning electron microscopy. Telia and teliospores were observed in mid-August. Hypophyllous telia often formed around uredinial clusters. Telia were 0.3 to 1.1 mm wide and erumpent with numerous teliospores in a compact layer. Teliospores were clavate, oblong to ellipsoidal, 60.2 to 120.8 × 12.1 to 24.4 μm, gelatinous, and one celled. Teliospores were four celled with the division of the protoplast into an internal four-celled basidium. Pathogenicity tests included inoculation of young P. koreana plants by spraying a urediniospore suspension (30,000 spores/ml of deionized water). Inoculated plants were incubated at 25°C for 48 h, and typical rust symptoms and uredinia developed in 10 to 15 days. On the basis of symptomatology, the host, and morphology of uredinial and telia, the fungus was identified as Coleosporium pulsatillae (Str.) Lév (2). The internal transcribed spacer (ITS) region was amplified using ITS1-F and ITS4-B primers (3), and an amplified product of 817 bp, specific for the species C. pulsatillae, was obtained. The sequence was deposited in GenBank (Accession No. JQ029765). Although this pathogen has been mentioned as part of a fungal species survey from China, it was not fully described (4). This pathogen has been reported on Anemone chinensis in Austria, Sibiria (2), and Korea (1). It has not been reported from anywhere else in China. To our knowledge, this is the first fully described record and most severe outbreak of C. pulsatillae on windflower. References: (1) W. D. Cho and H. D. Shin. List of Plant Diseases in Korea. Korean Society of Plant Pathology, Seoul, Korea, 2004. (2) J. B. De-Toni. Sylloge Fungorum 7:754, 1888. (3) M. Gardes et al. Mol. Ecol. 2:113, 1993. (4) F. L. Tai. Sylloge Fungorum Sinicorum. Science Press, Beijing, 1979.

Response surface optimization of phosphorus species adsorption onto powdered alum sludge

The purpose of this study is to optimize adsorption conditions of powdered alum sludge (PAS) as low-cost adsorbent for the removal of three P-species (ortho-P, poly-P and organic-P) from wastewater using the response surface methodology (RSM). Initially, RSM in the basis of a 3-variable Box-Behnken design was used to determine the effect of pH (from 4 to 7), PAS mass (from 0.1 to 0.5 g) and PAS particle size (from 125 to 420 microm) on the response levels (removal efficiencies of the three P-species). Three response surface quadratic models in terms of three factors were then obtained from an analysis of the experimental data using a SAS computer package. Thereafter, the effect of each of the parameters on P removal for each of the three species was examined using the three-dimensional response surface. All three parameters (pH, PAS mass and PAS particle size) had a significant effect on the removal of each of the P species. Finally, optimal conditions for P species removal were determined at which the P-removals of 99.8% (for ortho-P), 94.9% (for poly-P) and 94.8% (for organic-P) were achieved, respectively. The results derived from the verification experiments agreed with that predicted by the models, confirming the suitability of the established models and the success of RSM in optimizing the PAS adsorption conditions.

Conditioning of aluminium-based water treatment sludge with Fenton's reagent: effectiveness and optimising study to improve dewaterability

Alternative conditioning of aluminium-based drinking water treatment sludge using Fenton reagent (Fe2+/H2O2) was examined in this study. Focuses were placed on effectiveness and factors to affect such novel application of Fenton process. Experiments have demonstrated that considerable improvement of alum sludge dewaterability evaluated by capillary suction time (CST) can be obtained at the relative low concentrations of Fenton reagent. A Box-Behnken experimental design based on the response surface methodology was applied to evaluate the optimum of the influencing variables, i.e. iron concentration, hydrogen peroxide concentration and pH. The optimal values for Fe2+, H2O2, and pH are 21 mg g(-1)DS(-1)(dry solids), 105 mg g(-1)DS(-1) and 6, respectively, at which the CST reduction efficiency of 48+/-3% can be achieved, this agreed with that predicted by an established polynomial model in this study.

Type 1 diabetes mellitus in a child with phenobarbital hypersensitivity syndrome

OBJECTIVE

To report a case of type 1 diabetes mellitus (T1DM) in a child with phenobarbital hypersensitivity syndrome with an emphasis on the clinical presentation, diagnostic modalities and treatment options.

CASE SUMMARY

A 5-yr-old girl developed fever, rash and hepatic inflammation after receiving phenobarbital. Infection and connective tissue diseases were excluded and an adverse event following phenobarbital administration [anticonvulsant hypersensitivity syndrome (AHS)] was considered. Clinical manifestation was somewhat improved after systemic hydrocortisone and other antiallergic drugs were administrated. However, polyuria, polydipsia, dehydration, severe metabolic acidosis with increased anion gap and hyperglucosemia were found about 4 weeks after stopping phenobarbital. Increased blood ketone and glycosylated hemoglobin (HbA1c), and decreased blood insulin and C-peptide confirmed the diagnosis of T1DM. Insulin was used and gamma-immunoglobulin was administered on the 25th day after admission. Since then, clinical symptoms and signs improved significantly and the patient was discharged on the 45th day after admission. Postdischarge course was uneventful and the patient is well with sequential HbA1c of 7.3% 1 month after discharge.

CONCLUSIONS

AHS should be suspected in patients who develop unexplained systemic manifestations following exposure to aromatic antiepileptics, including phenobarbital. The timely recognition and treatment with corticosteroids and immunoglobulin is required and useful. The potential damage of beta-cells should be considered in patients with AHS.

IL-18 gene promoter ?137C/G and ?607C/A polymorphisms in Chinese Han children with type 1 diabetes mellitus

Type 1 diabetes mellitus (T1DM) is a heterogeneous autoimmune disease, and both environmental and genetic factors play a role in its pathogenesis. Interleukin (IL)-18 is a potent pro-inflammatory cytokine capable of inducing interferon-gamma production that is associated with the development of T1DM. The gene for IL-18 is located on chromosome 11q22.2-q22.3 and has been reported to be associated with a susceptibility to T1DM. To test the putative involvement between IL-18 gene polymorphism and predisposition to T1DM, we conducted a case-control study in Chinese Han children. The single nucleotide polymorphisms at position -607(C/A) and -137(C/G) in the promoter region of the IL-18 gene were analysed by sequence-specific primers-polymerase chain reaction in 118 patients with T1DM and 150 healthy controls. (1) The allele frequency of -607A was 41.2% and 53.0%, respectively, in patients and in control subjects (P = 0.01), but the allele frequency of -137C/G was not statistically significant (P = 0.37). (2) The distribution of CC genotype at position -607 was significantly different between patients and normal controls (P = 0.03), while the distribution of AA genotype in patients was significantly lower than that in the controls (P = 0.03). (3) Furthermore, there was a significant increase in haplotype (-137C/-607G) and genotype combination (-137GG/ -607CC) in patients compared with controls (P = 0.03 and P = 0.04, respectively). The results of this study show that IL-18 gene promoter polymorphisms confer susceptibility to T1DM in Chinese Han children. Moreover, subjects carrying AA genotype at position -607 of the promoter of IL-18 gene may be a low risk of T1DM development.

Several mutations in the melanocortin 4 receptor gene are associated with obesity in Chinese children and adolescents

AIM

To screen mutations in the melanocortin 4 receptor (MC4R) in obese and normal-weight Chinese children and adolescents.

METHODS

Three hundred Chinese children and adolescents, including 200 obese and 100 healthy non-obese individuals, were evaluated. The coding region of the MC4R gene was amplified by polymerase chain reaction (PCR) and sequenced.

RESULTS

In obese individuals, we detected two novel heterozygous non-synonymous mutations (c.496G>A, resulting in Val166Ile; c.929G>A, resulting in Arg310Lys) and a novel heterozygous non-sense mutation (c.831T>A, resulting in a premature stop codon Cys277Stop). In both obese individuals and controls, a novel heterozygous non-synonymous mutation (c.68T>G, resulting in Leu23Arg, 0.5 and 1%, respectively) and the Val103Ile polymorphism (c.307G>A, 3 and 2%, respectively) were found. There was no difference in alanine aminotransferase (ALT), aspartate aminotransferase (AST), triglyceride (TG), cholesterol (CHOL) and whole body insulin sensitivity index (WBISI) between obese individuals with and without mutation. The prevalence for heterozygous MC4R mutations was 1.5% in the obese.

CONCLUSIONS

Two novel heterozygous non-synonymous mutations (Val166Ile; Arg310Lys) and a novel heterozygous non-sense mutation (Cys277Stop) were detected in Chinese obese individuals. Leu23Arg variant might be a polymorphism in the Chinese population. There were no differences between clinical and biochemical profiles in the heterozygous mutations and the wild type.

Liver injury and hepatocyte apoptosis induced by chronic alcoholic intoxication in rats

AIM: To investigate the role of hepatocyte apoptosis in the pathogenesis of alcohol-induced liver diseases (ALD) in rats.

METHODS: The rat model of liver injury was induced by combination of drinking and gastric irrigation of ethanol. The morphological changes of the liver were observed by routine HE staining under light microscope. The hepatocyte apoptosis was examined by TUNEL, and the levels of serum alanine aminotransferase (ALT) and aspartate transaminase (AST) were detected by the rate method.

RESULTS: At the end of the 5^th week, the light and moderate steatosis appeared in ethanol-treated rat livers, the proportion of fatty degeneration was 40% (8/20); At the end of the 10^th week, the proportion was increased to 85%(17/20), and the morphological changes of alcoholic hepatitis (AH) were found in 45%(9/20) rats. The serum levels of ALT and AST (nkat/L) in ethanol-treated rats were significantly higher than those of the controls (5 wk: 1 017±267 vs 550±133, P < 0.05; 1 350±333 vs 967±150, P < 0.05; 10 wk: 1 500±267 vs 767±250, P < 0.05; 2 167±533 vs 850±183, P < 0.05), and ALT and AST levels at 10 wk were also higher than those at 5 wk (P < 0.05). The TUNEL indexes (%) in at 5 and 10 wk were 0.33±0.49 and 2.03±1.61 respectively (P < 0.05), and the index at 10 wk was significantly different from that of the controls (0.10±0.21, P < 0.05). Furthermore, the TUNEL index of alcoholic hepatitis was significantly higher than that of alcoholic fatty liver (3.24±1.50% vs 1.12±0.63%, P < 0.05). Both show the significant difference.

CONCLUSION: Chronic and excessive ethanol consumption can cause liver injury in rats. The amount and time of daily ethanol intake is closely related with the degrees of liver injury. Hepatocyte apoptosis may play an important role in the pathogenesis of ALD.

[Studies of treatment strategy and prognosis on acute myeloid leukemia with chromosome 8 and 21 translocation]

OBJECTIVE

To investigate the relationship between the biological features and the treatment efficacy and prognosis in acute myeloid leukemia subtype M2 (AML-M2) patients with chromosome 8 and 21 translocation.

METHODS

By using Cox regression model and Kaplan-Meier analyses, prognostic factors in 54 cases of de novo adult AML with t(8;21) in our institute from 1990 to 2003 were retrospectively analyzed.

RESULT

The complete remission (CR) rates were 81.9% for all M2 patients, 82.4% for patients with normal karyotype, 88.5% for patients with t(8;21) [P > 0.05 for normal karyotype vs t(8;21)], 100.0% for 28 patients with t(8;21) alone and 75.0% for 24 patients with additional chromosome abnormalities (P < 0.01). The actuarial 3 year overall survival(OS) was 26% for M2 patients with normal karyotype, 25% for patients with t(8;21) [P > 0.05 for normal karyotype vs t(8;21)], in whole t(8;21) group, 46.4% for patients with t(8;21) alone and 0% for patients with additional chromosome abnormalities (P < 0.01). Multivariate analysis of prognostic factors showed that chromosome abnormalities besides t(8;21) was the only factor affecting CR, disease-free survival (DFS) and OS. DFS of allogeneic hematopoietic stem cell transplantation (HSCT) and intermediate-dose cytarabine/high dose cytarabine (IDAC) groups were better than the group received routine dose cytarabine as postremission therapy (P < 0.01).

CONCLUSION

AML with t(8;21) is not a single defined AML subset, and patients with additional chromosome abnormalities have a worse prognosis. HSCT and IDAC could improve the outcome. HSCT is the best choice for patients with high risks, especially with additional chromosome abnormalities.

[Use of heterogeneous acelluar dermal matrix and autologous overthin split-thickness skin for repair of deep burn at articular sites]

OBJECTIVE

To investigate the effect of heterogeneous (swine) acellular dermal matrix (s-ADM) and autologous overthin split-thickness skin (auto-OTS) composite grafting in repair of deep burns at articular sites.

METHODS

From May 1999 to April 2000, 19 articular sites in 16 patients, including 14 males and 2 females, were treated. In all the 19 sites of deep burn, the total burn area varied from 2% to 48% and the full-thickness burn area varied from 1% to 35%. After the primary escharectomy (1 to 5 days later) and complete hemostasis, the s-ADM was utilized to cover the exposed articular sites and the auto-OTS was transferred on the surface of sutured s-ADM. The size of s-ADM applied to each patient varied from 25 cm2 to 150 cm2. Regular skin grafting was adopted elsewhere other than the articular site. The survival rate of all skin grafting was evaluated and pathological examination was performed.

RESULTS

The survival rate of the composite skin was (90.80 +/- 18.34)%, which was obvious higher than the survival rate of contiguous granulosum skin grafting (P < 0.05) and almost the same with that of snip skin grafting(P > 0.05). The survived composite skin appeared as smooth and soft as normal skin, and the function of articular site almost recovered with neglectable hypertrophic scar. The pathological examination revealed that the normal cell grew into s-ADM with regularly arranged collagen fiber and neovascularization in the matrix.

CONCLUSION

The combination of s-ADM and auto-OTS graft is cheap and effective method to cover wound and minimize hypertrophic scar.

Lack of BCL10 mutations in multiple myeloma and plasma cell leukemia

To determine whether the BCL10 mutation plays a role in the oncogenesis of plasma cell dyscrasias, we used polymerase chain reaction-single-strand conformation polymorphism (PCR-SSCP) and direct sequencing analysis and examined the genomic BCL10 mutations in 57 patients with multiple myeloma or plasma cell leukemia and 52 normal bone marrow samples. We found three polymorphic sequence variants, either alone or in combination, at codons 5 and 8, and in intron 1 at base 58 of the BCL10 gene in 37 patients with plasma cell dyscrasia. Identical aberrant band shifts were also observed in 34 normal marrow samples. No polymorphic variants were identified in exon 2 or 3 in either patient or control samples, and no pathogenic mutations were detected. Patients with plasma cell dyscrasias in Taiwan appeared to have a higher frequency of polymorphisms at codon 5 and intron 1 at base 58, and a lower frequency at codons 8 and 213. Our results suggest that BCL10 is not involved in the oncogenesis of plasma cell dyscrasias.

Simultaneous occurrence of multiple aetiologies of polycythaemia: renal cell carcinoma, sleep apnoea syndrome, and relative polycythaemia in a smoker with masked polycythaemia rubra vera

A 58 year old male heavy smoker presented with intracranial haemorrhage and erythrocytosis. Four aetiologies of polycythaemia--polycythaemia rubra vera (PRV), renal cell carcinoma, sleep apnoea syndrome, and relative polycythaemia--were found to be associated with the underlying causes of erythrocytosis. He did not fulfill the diagnostic criteria for PRV at initial presentation, but an erythropoietin independent erythroid progenitor assay identified the masked PRV, and the low post-phlebotomy erythropoietin concentration also suggested the likelihood of PRV evolution. This case demonstrates that a search for all the possible causes of erythrocytosis is warranted in patients who already have one aetiology of polycythaemia.

Isolation and characterization of plasmid pSW200 from Erwinia stewartii

The nucleotide sequence of pSW200 of Erwinia stewartii SW2 was determined. This plasmid is 4367 bp long, consisting of four mobilization genes, mobCABD, and an origin of replication homologous to those of ColE1-type plasmids. The plasmid also contains a region of forty-one 15-bp repeats. Deleting this region does not affect the stability or the copy number when maintained as sole plasmid in the cell. However, the plasmid is rapidly lost when a homoplasmid with the intact repeat region is introduced into the cell. The function of this region may provide pSW200 an advantage in competing with an incompatible plasmid in the cell.

Cloning and characterization of the ori region of pSW1200 of Erwinia stewartii: similarity with plasmid P1

The ori region of an Erwinia stewartii plasmid, pSW1200 (106 kb), has been cloned and sequenced. This region consists of a gene encoding a protein which has 91% similarity and 73% identity with the RepA protein of bacteriophage P1. The ori region also consists of eight copies of 19-bp iterons which are highly homologous to the iterons of P1. Similar to plasmid P1, pSW1200 replicon has a copy number of approximately 1. On the other hand, the copy number increases about ninefold if three of the iterons located downstream from repA gene are deleted. We also demonstrate that pGEM-5Z consisting of a copy of P1 iteron is incompatible with a pSW1200 derivative, pSW1201, suggesting that pSW1200 and P1 DNA are incompatible and both belong to the IncY group.

Characterization of the replicon of plasmid pSW500 of Erwinia stewartii

A 1.6-kb DNA region required for the replication of pSW500 from Erwinia stewartii SW2 has been identified. DNA sequencing analysis revealed that this DNA fragment consists of a DnaA box, seven 16-bp direct repeats, and a 1005-bp open reading frame. The seven direct repeats have been demonstrated to mediate the incompatibility function of the plasmid. Primer extension analysis showed that the 1005-bp ORF is transcribed in vivo and the +1 site of the transcript is located 113 bp upstream from the translation initiation codon of the ORF. Complementation studies showed that this ORF is required for the replication of the plasmid and may encode a replication protein, RepA. Gene fusion studies revealed that the expression of repA is autoregulated by RepA. We also found that the pSW500 replicon has a copy number of approximately two and that the plasmid is stably maintained in Escherichia coli, thus demonstrating that the replicon contains all the elements required for copy number control and plasmid stability in E. coli. Curing of pSW500 from E. stewartii SW2 revealed that loss of pSW500 did not have any obvious effect on morphology or physiology of the cells, suggesting that pSW500 does not encode a function that is indispensable for the survival of the organism.

Sequence analysis of an Erwinia stewartii plasmid, pSW100

The nucleotide sequence of the smallest plasmid of Erwinia stewartii SW2 was determined. This plasmid, pSW100 (4272 bp), consists of a 702-bp region homologous to the origins of replication of plasmids p15A, ColE1, and ColA. Plasmid pSW100 also contains sequences homologous to the bom region and mobCABD genes of ColE1, except that a single-base deletion in mobA has been detected. This deletion did not affect the mobilization ability of pSW100 by an endogenous conjugative plasmid of E. stewartii SW2, pDC250. Plasmid pSW100 also has a 1596-bp open reading frame with five 132-bp perfect repeats. However, this open reading frame and the repeats are not required for plasmid replication. Furthermore, curing of pSW100 did not cause any phenotypic change, suggesting that this plasmid is not essential for the survival of the organism.

Aberration antigen expression in adult acute myelocytic leukemias

Marrows from 58 newly diagnosed acute myelocytic leukemia (FAB-AML) patients were immunophenotyped by flow cytometry with 13 kinds of monoclonal antibodies. Marrows of 53.4% of the patients showed pure myeloid antigen expression (Ly-AML) and 34.5% displayed both myeloid and lymphocyte associated antigen expression (Ly+AML). In general, fluorescence intensity of lymphocyte associated antigen in Ly+AML was weaker than that of myeloid antigen. Myeloid and lymphoid marker cells distributed randomly in DNA-aneuploidy. It took more days to reach the first complete remission in Ly+AML. The aberration antigen expression in AML allows a sensitive detection of minimal residual leukemic cells in complete remission bone marrow and treatment stratification.

Construction of lactose-utilizing Xanthomonas campestris and production of xanthan gum from whey

Xanthomonas campestris pv. campestris possesses a low level of beta-galactosidase and therefore is not able to grow and produce significant amounts of xanthan gum in a medium containing lactose as the sole carbon source. In this study, a beta-galactosidase expression plasmid was constructed by ligating an X. campestris phage phi LO promoter with pKM005, a ColE1 replicon containing Escherichia coli lacZY genes and the lpp ribosome-binding site. It was then inserted into an IncP1 broad-host-range plasmid, pLT, and subsequently transferred by conjugation to X. campestris 17, where it was stably maintained. The lacZ gene under the control of the phage promoter was expressed at a high level, enabling the cells to grow in a medium containing lactose. Production of xanthan gum in lactose or diluted whey by the engineered strain was evaluated, and it was found to produce as much xanthan gum in these substrates as the cells did in a medium containing glucose.