[Association between congenital hypothyroidism and in-hospital adverse outcomes in very low birth weight infants]

Objective: To investigate the association between congenital hypothyroidism (CH) and the adverse outcomes during hospitalization in very low birth weight infants (VLBWI). Methods: This prospective, multicenter observational cohort study was conducted based on the data from the Sino-northern Neonatal Network (SNN). Data of 5 818 VLBWI with birth weight <1 500 g and gestational age between 24-<37 weeks that were admitted to the 37 neonatal intensive care units from January 1st, 2019 to December 31st, 2022 were collected and analyzed. Thyroid function was first screened at 7 to 10 days after birth, followed by weekly tests within the first 4 weeks, and retested at 36 weeks of corrected gestational age or before discharge. The VLBWI were assigned to the CH group or non-CH group. Chi-square test, Fisher exact probability method, Wilcoxon rank sum test, univariate and multivariate Logistic regression were used to analyze the relationship between CH and poor prognosis during hospitalization in VLBWI. Results: A total of 5 818 eligible VLBWI were enrolled, with 2 982 (51.3%) males and the gestational age of 30 (29, 31) weeks. The incidence of CH was 5.5% (319 VLBWI). Among the CH group, only 121 VLBWI (37.9%) were diagnosed at the first screening. Univariate Logistic regression analysis showed that CH was associated with increased incidence of extrauterine growth retardation (EUGR) (OR=1.31(1.04-1.64), P<0.05) and retinopathy of prematurity (ROP) of stage Ⅲ and above (OR=1.74(1.11-2.75), P<0.05). However, multivariate Logistic regression analysis showed no significant correlation between CH and EUGR, moderate to severe bronchopulmonary dysplasia, grade Ⅲ to Ⅳ intraventricular hemorrhage, neonatal necrotizing enterocolitis in stage Ⅱ or above, and ROP in stage Ⅲ or above (OR=1.04 (0.81-1.33), 0.79 (0.54-1.15), 1.15 (0.58-2.26), 1.43 (0.81-2.53), 1.12 (0.70-1.80), all P>0.05). Conclusion: There is no significant correlation between CH and in-hospital adverse outcomes, possibly due to timely diagnosis and active replacement therapy.

[Effect of EIT-guided individualized PEEP setting on the incidence of hypoxemia in elderly patients undergoing robot-assisted radical prostatectomy]

Objective: To investigate the effect of individualized positive end expiratory pressure (PEEP) setting guided by chest electrical impedance tomography (EIT) on the incidence of hypoxemia in elderly patients undergoing robot-assisted radical prostatectomy in the post anesthesia care unit (PACU). Methods: From September 2020 to October 2021, sixty elderly patients, with the American Association of Anesthesiologists (ASA) of Grade Ⅰ to Ⅲ, who underwent selective robot-assisted radical prostatectomy under general anesthesia in the Cancer Hospital Affiliated to Fudan University were selected. The participants were divided into two groups by the minimum randomized grouping method: EIT-PEEP group (EP group, n=30) and fixed PEEP group (FP group, n=30). After completion of tracheal intubation and establishment of pneumoperitoneum flexion posture, the individualized PEEP setting was guided by EIT in EP group, and the PEEP setting in FP group was 5 cmH₂O (1 cmH₂O=0.098 kPa) to the end of operation. During the operation, the ventilation mode of pressure regulation volume control was adopted. The driving pressure, dynamic lung compliance (Cdyn), oxygenation index and hemodynamics were recorded at 5 min (T₁), 30 min (T₂), 60 min (T₃) after PEEP setting and at the time of tracheal catheter removal (T₄) in both groups. The primary end point was the incidence of hypoxemia in PACU after extubation. Results: The incidence of hypoxemia after extubation was 3.3% (1/30) in EP group and 26.7% (8/30) in FP group (P=0.030). The difference of driving pressure between the two groups at T₂ [(13.1±2.4) cmH₂O vs (14.9±2.9) cmH₂O, P=0.012], T₃ [(12.7±2.4) cmH₂O vs (15.6±2.8) cmH₂O, P<0.001] was statistically significant. In EP group, Cdyn was improved at T₂ [(38.4±7.2) ml/cmH₂O vs (31.9±5.2) ml/cmH₂O, P=0.006] and T₃ [(37.5±9.0) ml/cmH₂O vs (30.4±5.9) ml/cmH₂O, P=0.001]. In EP group, PaO₂/FiO₂ increased at T₁ [(465.7±84.5) mmHg vs (383.5±58.0) mmHg, 1 mmHg=0.133 kPa, P<0.001], T₂ [(504.7±105.8) mmHg vs (418.9±73.7) mmHg, P=0.001], T₃ [(520.7±92.2) mmHg vs (423.2±90.7) mmHg, P<0.001], T₄ [(368.7±42.0) mmHg vs (339.5±54.9) mmHg, P=0.024]. Conclusion: The individualized PEEP setting guided by EIT can reduce the incidence of hypoxemia in elderly patients undergoing robot assisted radical prostatectomy in PACU.

[Contrastive analysis about the postoperative clinical characteristics of elderly patients with colorectal cancer in different age groups]

Objective: To explore the postoperative clinical characteristics of elderly patients with colorectal cancer at different ages. Methods: Retrospective analysis was performed on the clinical data of 720 elderly patients with Colorectal Cancer in Beijing Hospitals from January 2012 to December 2019. There were 411 males and 309 females with a median age of 74 years. We divided the patients into young-old, old-old, oldest-old colorectal cancer patient groups and used chi-square comparative analysis of different groups of patients with clinical disease characteristics. Results: The oldest-old colorectal cancer patients tended to have normal body mass index (BMI), and the site of the disease shifted to the right. The incidence of concomitant diseases such as heart disease and hypertension increases gradually with age, and the incidence of diabetes is highest in old-old colorectal cancer patients. The proportion of open surgery was higher in the oldest-old group, but the operation time was shorter than the other two groups. In addition, the incidence of postoperative complications in elderly patients with colorectal cancer gradually increases with age, especially cardiac complications and other complications such as pneumonia, deep venous thrombosis of lower limbs, urinary retention, urinary tract infection, renal failure, cerebral hemorrhage, cerebral infarction, and so on. Conclusions: The BMI of the oldest-old patients tended to be normal, and the site of the disease shifted to the right. The incidence of heart disease, hypertension, and other concomitant diseases and postoperative complications in elderly patients with colorectal cancer gradually increase with age. Thus, the choice of treatment should be more individualized for elderly patients with colorectal cancer, and more attention should be paid to perioperative management.

[Diagnosis and treatment of two imported cases with schistosomiasis haematobia in Fujian Province]

OBJECTIVE

To analyze the diagnosis and treatment of two imported cases with schistosomiasis haematobia, so as to provide insights into improving the diagnosis and treatment and avoiding misdiagnosis and mistreatment of imported schistosomiasis haematobia.

METHODS

The medical records and epidemiological data pertaining to the two cases were collected. The stool and urine samples were collected for identification of Schistosoma eggs using the Kato-Katz technique and direct smear method after centrifugal precipitation, and blood samples were collected for detection of anti-Schistosoma antibody. Following definitive diagnosis, the patients were given praziquantel therapy.

RESULTS

The patient 1, a Malagasy, was infected in Madagascar and returned to China for delivery. The case presented intermittent painless terminal hematuria symptoms, and showed no remarkable improvements following multiple-round treatments in several hospitals. In January 2017, she was found to be positive for anti-Schistosoma antibody, negative for feces test, and positive for S. haematobium eggs in urine test, and miracidia were hatched from eggs. Then, the case was diagnosed as schistosomiasis haematobia. Patient 2 worked in Republic of Malawi for many years, and presented intermittent painless terminal hematuria since October 2018; however, no definite diagnosis or effective treatment was received after admission to multiple hospitals. In March 2019, pathological examinations showed a number of eggs in the interstitium of the bladder mass, accompanied by a large number of eosinophils, which was consistent with schistosomiasis cystitis. In April 2019, he was tested positive for serum anti-Schistosoma antibody, negative for the fecal test, and had S. haematobium eggs in urine samples, with miracidia hatched from eggs. Then, the case was diagnosed as schistosomiasis haematobia. Following treatment with praziquantel at a dose of 60 mg/kg, all symptoms disappeared.

CONCLUSIONS

Overseas imported schistosomiasis haematobia is likely to be misdiagnosed. The training pertaining to schistosomiasis control knowledge requires to be improved among clinical professionals, in order to avoid misdiagnosis and mistreatment.

Population Pharmacokinetics and Pharmacodynamics of Norvancomycin in Children With Malignant Hematological Disease

Knowledge of pharmacokinetic (PK) behavior of norvancomycin (NVCM) in pediatric patients is lacking, which leads to empirical therapy in clinical practice. This study developed a population PK model of children aged 0-15 years; 112 opportunistic samples in total from 90 children were analyzed. The stability and prediction of the final model were evaluated by goodness-of-fit plots, nonparametric bootstrap, visual predictive check, and normalized prediction distribution errors. The PKs of NVCM in children was described by a 2-compartment model with first-order elimination along with body weight and estimated glomerular filtration rate as significant covariates on clearance. The population typical values of the PK parameters were as follows: clearance 0.12 L/kg/h, central compartment distribution volume 0.17 L/kg, peripheral compartment distribution volume 0.38 L/kg, and intercompartmental clearance 0.35 L/kg/h. Logistic analysis showed that the ratio of area under the concentration-time curve over 24 hours (AUC_0-24 ) to minimum inhibitory concentration (MIC) had the strongest correlation with clinical efficacy, and at least 80% clinical efficiency could be achieved when AUC_0-24 /MIC ≥ 221.06 was defined as the target. Monte Carlo simulation results suggested that a higher dose was required for this pediatric population in order to reach the target. The dosing regimen was optimized based on the final model. A population PK model of NVCM was first characterized in children with hematologic malignancy, and an evidence-based approach for NVCM dosage individualization was provided.

Population Pharmacokinetics of Caspofungin and Dosing Optimization in Children With Allogeneic Hematopoietic Stem Cell Transplantation

Caspofungin is the first echinocandin antifungal agent that licented for pediatric use in invasive candidiasis and aspergillosis. In this study, we evaluated the population pharmacokinetics of caspofungin and investigate appropriate dosing optimization against Candida spp. in children with allogeneic hematopoietic stem cell transplantation (allo-HSCT) in order to improve therapeutic efficacy. All participants received a recommended caspofungin 70 mg/m² loading dose followed by 50 mg/m² maintenance dose. A one-compartment model with first-order elimination was best fitted the data from 48 pediatric patients. Body surface area and aspartate aminotransferase had significant influence on caspofungin clearance from covariate analysis. Our results reviewed that dose adjustment is not necessary in patients with mild liver dysfunction. Monte Carlo simulations were performed using pharmacokinetic data from our study to evaluate the probability of target attainment (PTA) of caspofungin regimen in terms of AUC₂₄/MIC targets against Candida spp. The results of simulations predicted that a caspofungin 70 mg/m² at first dose, 50 mg/m² of daily dose may have a high probability of successful outcome against C. albicans and C. glabrata whilst 60 mg/m² maintenance dose was required for fungistatic target against C. parapsilosis but may be not sufficient to achieve optimal fungicidal activity. Caspofungin standard regimen had high probability of successful outcome against C. albicans (MIC ⩽ 0.25 mg/L) and C. glabrata (MIC ⩽ 0.5 mg/L) but insufficient for C. parapsilosis with MIC > 0.25 mg/L. That may provide an evidence based support to caspofungin individualized administration and decrease the risk of therapeutic failure in allo-HSCT pediatric patients.

[Prevalence of high-risk HPV and its distribution in cervical precancerous lesions among 35-64 years old women who received cervical cancer screening in Beijing]

Objective: To study the prevalence of high-risk HPV (HR HPV) in women who accepted cervical cancer screening in Beijing and its distribution in cervical precancerous lesions. Methods: From January 2014 to March 2015, all women aged 35-64 years old and received free screening in institutions of cervical cancer in Beijing were recruited. Stratified cluster random sampling method was used in selecting 31 091 women for gynecological examination and genotyping of HR-HPV. Those positive for HR-HPV (except for HPV 16/18) were examined for cervical cell. For those atypical squamous cells of uncertain significance (ASCUS) and above, who were positive for HPV 16/18 and with uncertain results for cervical cell, were transferred for colposcopy examination. For those with suspicious or abnormal results for colposcopy, were transferred for histopathology. The prevalence of HR-HPV, cervical cancer and precancerous lesions among the participants were analyzed. Results: Totally 31 091 women aged from 35-year-old to 64-year-old, with 44.3% (13 780 women) in the 35-49 age group and 55.7% (17 311 women) in the 50-64 age group. 66.1% (20 536 women) were rural women. The infection rate of HR-HPV was 7.4%(2 305 cases) among the women. High-risk infection rates of HPV except HPV 16/18 were 5.7% (1 758 cases), and multi-infection rate was 1.5% (477 cases). The highest infection rate was 7.9% (1 044 cases) among the 45-49 year-old and 50-54 year-old age groups (χ(2)=14.07, P=0.015). The rate in rural women was significantly higher than that of the urban women (6.2%, 507 cases; 7.9%, 1 798 cases) (χ(2)=25.75, P<0.001). The proportion of HPV16, HPV18, HPV52, HPV51, HPV58 was 17.0% (391 cases), 6.9% (161 cases), 8.6% (20 cases), 5.2% (12 cases) and 7.7% (18 cases), respectively. The detection rate of cervical cancer and precancerous lesions in the population was 395.6/100 000 (123 cases). In high-grade squamous intraepithelial lesions (HSIL), HPV16 and 18 infections accounted for 60.5% (72 cases) of all. HPV16 infection rate and detection rate of HSIL were the highest in 50-54 year-old group which were 1.5% (107 cases) and 25.2% (30 cases) (χ(2)=11.54, P=0.042). Conclusion: Top five types of HR-HPV infection in women who accepted cervical cancer screening in Beijing were HPV16, 18, 52, 51 and 58. The infection rate of HPV16 and 18 increased significantly in HSIL women. HPV16 infection rate and detection rate of HSIL were the highest in 50-54 year-old age group.

[Effect of low-dose or standard-dose conjugated equine estrogen combined with different progesterone on bone density in menopause syndrome women]

Objective: To explore the effect of low-dose or standard-dose conjugated equine estrogen (CEE) combined with natural progesterone or dydrogesterone on bone density in menopause syndrome women. Methods: Totally 123 patients with menopause syndrome were recruited and randomly assigned to 3 treatment groups: group A (low-dose CEE+progesterone) , group B (standard-dose CEE+progesterone) , group C (standard-dose CEE+dydrogesterone) . Using continuous sequential regimen, the duration of intervention was 12 cycles. The bone mineral density of lumbar 2-4 and neck of femur, the bone metabolic markers, the level of FSH and estradiol were examined just before the drug administration and 12 months after the beginning of experiment. Results: There were 107 cases completed the one year trial. (1) Bone density: after 12 cycles of treatment, there was no significant change in bone density in group A (P>0.05) ; lumbar vertebrae of group B and C increased significantly, at 3.0% and 2.1%respectively (all P<0.05) . The bone density of left femoral neck of group C significantly increased by 2.9% (P=0.029) . There was no significant difference among the treatment groups at the beginning of experiment (P>0.05) . (2) Bone metabolic markers: after 12 cycles of treatment, the levels of calcium, phosphorus, alkaline phosphatase, Ca/Cr decreased significantly, the difference were statistically significant (all P<0.05) . There was no significant difference among the treatment groups at the beginning of experiment (P>0.05) . (3) Levels of FSH and estradiol: after 12 cycles of treatment, the levels of FSH in three groups were decreased significantly (all P<0.01) . The levels of estradiol in three groups were increased significantly (all P<0.01) . There was no significant difference among the treatment groups at the beginning of experiment (P>0.05) . Conclusions: Both low-dose and standard-dose menopause hormone therapy (MHT) could elevate the level of estradiol, reduce bone turnover, prevent bone loss of postmenopausal women effectively. The standard dose of MHT could also increase the density of vertebrae and femoral neck, and generate more clinical benefits.

[Analysis of clinical features of 23 patients with POEMS syndrome]

OBJECTIVE

To describe the endocrine abnormalities in patients with POEMS syndrome in order to identify more patients with POEMS syndrome among those who have endocrine dysfunctions.

METHODS

We searched the inpatient medical record system of Peking University People's Hospital with "POEMS syndrome". Finally the data from 23 patients were analyzed. Epidata 3.0 was used for data entering and SPSS 19.0 was used for statistical analysis.

RESULTS

The median age of all the 23 patients was 47 years. The ratio of male to female was 1.88:1. Polyneuropathy was the most common initial symptom which accounted for 56.5% in the 23 patients. The median duration from the initial symptoms to diagnosis as POEMS syndrome was 30 months. Among all the departments, the number of confirmed cases was highest in the department of neurology. The median duration from the onset of initial symptoms (6 months) to the diagnosis made in neurology department was also significantly shorter than in other departments. Among all the 23 patients, 100.0% of them had polyneuropathy, 82.6% had organomegaly, 95.7% had endocrinopathy, 52.2% were M protein positive, 91.3% had skin changes, 45.5% had papilledema, 43.5% had extravascular volume overload, 43.5% had platelet elevation and 17.4% had Castleman disease. Among all the patients with endocrinopathy, the incidence of hyperprolactinemia was 60.0% which was the highest one followed by thyroid dysfunction and adrenal dysfunction. Among the patients who had endocrine system dysfunctions, most of them had two target endocrine glands involved (36.5%).

CONCLUSION

Endocrinopathy is an important component of POEMS syndrome and it is of great importance to pay more attention to POEMS syndrome in patients with thyroid dysfunction, adrenal dysfunction, gonadal dysfunction, parathyroid dysfunction, hyperprolactinemia and glucose intolerance, especially in patients with two or more target gland dysfunctions. Symptoms and signs of polyneuropathy should be assessed carefully to reduce misdiagnosis of POEMS syndrome. Evaluation of the endocrine system should also be done in patients diagnosed with POEMS syndrome in order to treat the patients properly.

[PrepFiler Express BTATM Lysis Buffer Combined with Silicon Microbeads for Rapid DNA Extraction from Bone]

OBJECTIVES

To establish a convenient and rapid method for extracting DNA from bone.

METHODS

Fifteen long bone samples were washed and sterilized. The skeletal fragments were obtained by electric drill, and lysed by PrepFiler Express BTA™ lysis buffer. DNA was then manually extracted by silicon microbeads for further analysis.

RESULTS

STR genotyping was successfully obtained in 14 out of the 15 samples, and the detection rate was 93.33%.

CONCLUSIONS

The method for DNA extraction from bone established in present study is convenient, quick, effective, and with a strong applicability, which is worth spreading and applying.

An update on acupuncture point injection

This overview reports the global research advances in acupuncture point injection in the last 5 years. Acupuncture point injection can be applied to a wide range of curable diseases, predominantly those involving pain, but it has poor clinical evidence. Progress has been attained in the mechanism research on acupuncture point injection, but further studies remain necessary. With the reported adverse effects of acupuncture point injection, the need to standardize its clinical procedure has become urgent.

Immune protective mechanism of rMOMP protein ophthalmic vaccine regarding intraocular hypertension and retinal optic nerve injury in rats

The aim of this study was to explore the immune protective mechanism of rMOMP protein vaccine in intraocular hypertension and retinal optic nerve injury in rats. The rMOMP protein ophthalmic vaccine was prepared and quality-controlled. Sixty normal adult SD rats were randomly divided into two groups to establish a chronic ocular hypertension model and an optic nerve injury model. The model rats were vaccinated with rMOMP-CS ophthalmic vaccine. Fluorogold retrograde tracing was used to observe retinal ganglion cells, and an immunofluorescence method to determine the expression of retinal GAP43, CD3, BDNF, and GDNF. rMOMP protein ophthalmic vaccine met the requirements for medicinal use. The number of retinal ganglion cells (RGCs) of the rMOMP-CS group in the chronic ocular hypertension model was significantly higher than that of the CS group (P < 0.05). The count of RGCs of the rMOMP-CS group in the optic nerve clamping injury model was significantly higher than that of the CS group (P < 0.01). Thus, rMOMP protein ophthalmic vaccine can induce an increase in the expression of retinal neurotrophic factors, thereby exerting a protective effect on damaged retinal optic nerve.

Etiology of Moldy Core, Core Browning, and Core Rot of Fuji Apple in China

'Fuji' apple fruit were collected in Shaanxi Province, China, and 186 fungal isolates were obtained from the fruit core region. Fungi were isolated from fruit with symptomless core regions, as well as from the core regions of fruit showing browning, typical moldy core, or core rot. Based on phylogenetic and morphological analysis, all fungi were identified to species. Pathogenicity was determined by cutting apple fruit into halves and daubing spore suspensions containing 1 × 10⁴ up to 1 × 10⁸ spores/ml on the carpel in the core region. Pathogenicity varied significantly among genera, with Alternaria and Cladosporium spp. causing core browning at lower spore concentrations and moldy core at higher spore concentrations. Combinations of pathogens initiated more browning and moldy core than the pathogens applied alone. Epicoccum and Phoma spp. predominated in dry core rot, whereas primarily Trichothecium but also Fusarium and Penicillium spp. caused wet core rot. Core browning was introduced as a new type of core symptom, along with moldy core, dry core rot, and wet core rot. Alternaria alternata, A. tenuissima, A. arborescens, Cladosporium cladosporioides, and C. tenuissimum were the main pathogens causing core browning and moldy core.

Expression and properties of hyperpolarization-activated current in rat dorsal root ganglion neurons with known sensory function

The hyperpolarization-activated current (I(h)) has been implicated in nociception/pain, but its expression levels in nociceptors remained unknown. We recorded I(h) magnitude and properties by voltage clamp from dorsal root ganglion (DRG) neurons in vivo, after classifying them as nociceptive or low-threshold-mechanoreceptors (LTMs) and as having C-, Aδ- or Aα/β-conduction velocities (CVs). For both nociceptors andLTMs, I(h) amplitude and I(h) density (at -100 mV) were significantly positively correlated with CV.Median I(h) magnitudes and I(h) density in neuronal subgroupswere respectively:muscle spindle afferents(MSAs):-4.6 nA,-33 pA pF(-1); cutaneous Aα/β LTMs: -2.2 nA, -20 pA pF(-1); Aβ-nociceptors: -2.6 nA, -21 pA pF(-1); both Aδ-LTMs and nociceptors: -1.3 nA, ∼-14 pA pF(-1); C-LTMs: -0.4 nA, -7.6 pA pF(-1); and C-nociceptors: -0.26 nA, -5 pApF(-1). I(h) activation slow time constants (slow τ values) were strongly correlated with fast τ values; both were shortest in MSAs. Most neurons had τ values consistent with HCN1-related I(h); others had τ values closer to HCN1+HCN2 channels, or HCN2 in the presence of cAMP. In contrast, median half-activation voltages (V(0.5)) of -80 to -86 mV for neuronal subgroups suggest contributions of HCN2 to I(h). τ values were unrelated to CV but were inversely correlated with I(h) and I(h) density for all non-MSA LTMs, and for Aδ-nociceptors. From activation curves ∼2-7% of I(h)would be activated at normal membrane potentials. The high I(h) may be important for excitability of A-nociceptors (responsible for sharp/pricking-type pain) and Aα/β-LTMs (tactile sensations and proprioception). Underlying HCN expression in these subgroups therefore needs to be determined. Altered high I(h) may be important for excitability of A-nociceptors (responsible for sharp/pricking-type pain) and Aα/β-LTMs (tactile sensations and proprioception). Underlying HCN expression in these subgroups therefore needs to be determined. Altered Ih expression and/or properties (e.g. in chronic/pathological pain states) may influence both nociceptor and LTM excitability.expression and/or properties (e.g. in chronic/pathological pain states) may influence both nociceptor and LTM excitability.

First Report of Botryosphaeria dothidea Causing Canker and Shoot Blight of Eucalyptus in China

Eucalyptus spp. are grown on approximately 2 million ha in China and is the most important genus in forest plantations worldwide. An outbreak of cankers and shoot blight was observed for the first time on Eucalyptus grandis in China during May of 2008. Symptoms included dieback of shoots and branches, lesions and canker formation on the stems, and clear or yellow-to-red exudates on stems and branches. Isolations were made from affected trees in Shilin County from May to July of 2008. Diseased samples were plated on potato dextrose agar (PDA) and incubated at 26°C. Fungal isolates developed copious, white, aerial mycelium that became dark gray after 5 to 6 days and formed black pycnidia after 14 days. Conidia were hyaline, aseptate, thin walled, fusiform, and measured 19 to 28 × 4 to 6 μm. Ascospores were hyaline, aseptate, and widest from the middle to upper third (17 to 28 × 6 to 13 μm). Identity was confirmed by analysis of the rDNA internal transcribed spacer region (ITSI-5.8S-ITS2) with primers ITS1 and ITS4. BLAST searches showed 99 to 100% identity with Botryosphaeria dothidea isolates from GenBank (Accession Nos. FJ358703 and EU080916). Representative sequences of B. dothidea from eucalyptus from China were deposited into GenBank (Accession Nos. FJ517657 and FJ517658). On the basis of morphological and molecular results, the fungus isolated from diseased eucalyptus wood was confirmed to be B. dothidea. Pathogenicity tests were conducted by stem inoculation of 10-month-old E. grandis seedlings. Two experiments were conducted using two inoculation techniques. In the first experiment, 2-mm-diameter actively growing mycelium plugs of B. dothidea were applied to 2-mm-long bark wounds on the middle point of the stems, and control seedlings were inoculated with sterile PDA plugs in a similar fashion as above. Inoculated and control seedlings were inoculated in a greenhouse and watered as needed. In the second experiment, segments of branches (averaging 18 mm in diameter and 30 cm long) were inoculated with 5-mm-diameter plugs of actively growing mycelium. Control segments of branches were inoculated as previously described. The branches were incubated at 26°C in moist chambers. There were five replicate seedlings per inoculation technique. After 20 days, all E. grandis seedlings showed leaf wilting, Dark, vascular stem tissue was observed. Symptoms were more abundant on the segment of branches. After 6 days, vascular necroses that developed on the inoculated plants were 5.2 ± 1.2 cm. B. dothidea was reisolated from all inoculated symptomatic tissue; no symptoms were visible in the control seedlings and no fungus was isolated from them. These results confirm previous reports of B. dothidea causing canker and dieback symptoms of Eucalyptus species in Australia (2), the United States (1), and South Africa (3). To our knowledge, this is the first report of B. dothidea causing canker disease on eucalyptus in China. References: (1) E. L. Barnard et al. Plant Dis. 71:358, 1987. (2) E. M. Davison and C. S. Tay. Plant Dis. 67:1285, 1983. (3) H. Smith et al. Plant Pathol. 43:1031, 1994.

Inhibition of reverse transcriptase activity of hepatitis B virus polymerase by β-l-D4A-TP

β-L-enantiomer of 2',3'-didehydro-2',3'-dideoxyadenosine-5'-triphosphate (β-L-D4A-TP) has previously been proven to inhibit the replication of viral DNA in the Hep G2 2.2.15 cells and in transgenic mouse harboring 1.3-fold-overlength genome of Hepatitis B virus (HBV). To study the inhibition mechanism of the nucleoside analog β-L-D4A-TP, a polymerase reaction in vitro with the recombinant HBV nucleocapsids was conducted to determine the exact mode of inhibition of the HBV replication by β-L-D4A-TP. The HBV viral DNA and viral DNA-polymerase complex formed in the polymerase reaction were assayed. The results of this study showed that β-L-D4A-TP inhibited the replication of HBV DNA by inactivating the reverse transcriptase (RT) activity in a concentration-dependent manner. The kinetics of β-L-D4A-TP inhibition of the RT activity was the result of an apparent competitive inhibition with dATP.

[cDNA cloning and sequencing of human urokinase receptor]

Human urokinase receptor (uPAR), a 55 kD glycoprotein linked to the cell membrane by a glycosylphosphatidylinositol anchor, plays a central role in cell migration and tissue remodeling. The human uPAR cDNA was cloned from a highly metastatic human lung giant cell line PG by RT-PCR and then subcloned into pGEM-T vector and sequenced. The data indicate that there are three bases substitution (705, 746, 755) which subsequently leads to two amino acid mutation (249, 252) compared to that of previously reported. The cDNA sequence of uPAR was registered in GenBank with accession number AF257789.