[Preliminary study on the effect of fecal microbiota transplantation on neurobehavior and gut microbiota of offspring rats exposed to arsenic].

Objective: To explore the effects of fecal microbiota transplantation (FMT) on neurobehavior and gut microbiota of arsenic-exposed offspring rats. Methods: In April 2021, Thirty-six SPF SD rats aged 8 weeks were seleted, rats were ranked by weight and divided into four groups according to randomized block design, namely control group, arsenic exposure group (As group) , arsenic+normal saline group (As+NaCl group) and As+FMT group, 6 females and 3 males in each group. Fecal microbiota fluid were provided by feces of rats in control group. Rats drank tap water containing 75 mg/L sodium arsenite for one week and then were caged together. The arsenic exposure was terminated until the pups were born. Female rats with vaginal plug were treated with fecal microbiota fluid via gavage during neurodevelopmental teratogenic window period. The volume of gavage was 1 ml/100 g with once every two days, for a total of three times. Weight alterations of offspring rats were recorded every week after weaning, and when offspring rats grew up for 6 weeks, Morris test and open field experiment was used to observe learning and memory abilities, as well as neurobehavioral performance of autonomous exploration and tension, respectively. 16S rDNA sequencing technology was used to detect microbiota diversities in fecal samples of rats in As group and As+FMT group. Results: Compared with the control group, the ratio of swimming distance and staying time in the target quadrant and the times of crossing the platform of rats in As group decreased significantly, and the motor distance, times entering central zone and the number of grid crossing of rats decreased significantly (P<0.05) . Compared with As group, the ratio of swimming distance in target quadrant, the motor distance in central zone and times entering central zone of rats in As+FMT group were evidently increased (P<0.05) . The analysis of fecal microbiota diversities showed that, at the phyla level, the relative abundance of Bacteroidetes in feces of rats in As+FMT group was higher than that in As group (68.34% vs 60.55%) , while the relative abundance of Firmicutes was lower than that in As group (28.02% vs 33.48%) . At the genus level, the relative abundance of Prevotella in As+FMT group was significantly higher than that in As group, becoming the dominant genus (42.08% vs 21.78%) . Additionally, compared with As group, a total of 22 genus were increased with 21 decreased genus in As+FMT group (P<0.05) . LEfSe analysis showed that dominant genuses in As+FMT group were Prevotella and UCG_005, and their relative abundance was significantly higher than that of As group (P<0.05) . Conclusion: FMT may alleviate the impaired learning and memory ability and anxiety like behavior of the offspring rats exposed to arsenic, and improve the disrupted gut microbiota.

[Analysis of clinical characteristics of 17 patients with inhalation dimethyl sulfate poisoning].

This paper analyzed the clinical data of 17 patients with inhalation dimethyl sulfate poisoning in Changzhou Third People's Hospital, in order to understand the clinical characteristics, treatment and prognosis of patients with inhalation dimethyl sulfate poisoning, and guide clinicians to make effective measures in time. Dimethyl sulfate poisoning progresses rapidly and dangerously. The prognosis is usually better if the patients are separated from the toxic environment as soon as possible, given glucocorticoids in early and short-term, closely observed respiratory tract injury, and treated with endotracheal intubation and invasive mechanical ventilation when necessary.

Identification of the most appropriate existing anthropometric index for home-based obesity screening in children and adolescents.

OBJECTIVES: Home-based self-screening and monitoring for obesity is particularly valuable for the prevention and control of chronic diseases. This study aimed to identify an anthropometric index suitable for home-based obesity screening in children and adolescents. STUDY DESIGN: The design of this study is a cross-sectional study. METHODS: A total of 14,042 students (6-17 years) from the Qibao Community, Minhang District, Shanghai, were studied in 2018. The percentage body fat (PBF), height, weight, waist circumference (WC) and hip circumference were measured. Body mass index (BMI), triponderal mass index (TMI), body adiposity index (BAI), waist-to-hip ratio (WHR) and waist-to-height ratio (WHtR) were calculated. Partial correlation analysis was used to evaluate the relationships between these indices and PBF, and receiver operating characteristic (ROC) curves were used to evaluate their performance for obesity screening. RESULTS: BMI, TMI, WC and WHtR were found to strongly correlate with PBF (r ≥ 0.830, all P < 0.001). The optimal index for obesity screening in children (6-11 years) was BMI (area under the ROC curve [AUC] = 0.980 for boys and 0.981 for girls) and in adolescents (12-17 years) was TIM (AUC = 0.976 for boys and 0.945 for girls); however, the optimal cut-off values for BMI and TMI differed among the subgroups. The ROC curve analysis showed that WHtR had similar cut-off values in each subgroup (0.45 for boys of 6-11 years and 0.43 for the other subgroups), excellent performance in children (AUC>0.90) and good performance in adolescents (AUC = 0.960 for girls and 0.878 for boys). CONCLUSIONS: Owing to its accuracy and stable cut-off value for defining obesity, WHtR should be recommended for home-based obesity screening in children and adolescents.

[Bronchoalveolar lavage fluid was used to diagnose two cases of 2019-nCoV infection].

The case reports 2 cases of novel coronavirus pneumonia diagnosed by concurrent bronchoalveolar lavage in our hospital, 1 case had a history of epidemiology, clinical symptoms and high imaging suspicion, but repeated negative throat swabs. One patient was diagnosed 2019-nCoV. Before the patient was discharged, the clinical symptoms disappeared, the chest CT showed significant improvement, and the pharynx swab was twice negative, reaching the discharge standard.We detected the ORF 1ab gene, the N gene and the nucleic acid of the new coronavirus in the broncho-alveolar lavage fluid of 2 patients. The results showed that the positive rate of bronchoalveolar lavage for detection of new coronavirus nucleic acid was high, and bronchoalveolar lavage for suspected or confirmed new coronavirus pneumonia patients with negative detection of nucleic acid in pharynx swabs but still residual lung lesions was helpful for early diagnosis, treatment and prognosis.

[Focus on diagnosis and treatment of genetic liver disorders].

The advancement and popularization of molecular diagnostic techniques has challenged and redefined the traditional concept of genetic metabolic disease. Regardless of disease origin, all genetic defects that lead to hepatobiliary dysfunction or structural abnormalities are termed as genetic liver disorders. Online Mendelian Inheritance in Man (OMIM) is a database consisting 693 genetic diseases with clear molecular mechanism of liver related phenotypes. Moreover, the effective measures to control infectious liver disease have strengthened the importance of research in the field of (adult and children) genetic liver disorders at home and abroad by well-recognized hepatologists. Notably, all patients with unexplained hepatopathy and multiple system diseases involving liver and gallbladder needs screening for genetic liver disorders, except for factors such as infection, immunity, drug-related, and anatomical abnormalities. We hope more patients with complicated liver disorders will benefit from definitive diagnosis and effective treatment in the near future with clear explanation of clinical phenotype, genotype, and metabolomics.

[Research Progress on Individual Identification Using Forensic Imaging Data under the Influence of Evidence Rule].

With the progress and development of the DNA test and imaging technique, and the evolution of evidence rule which bring the discussions about whether the individual identification using imaging data is outdated, and other disputes such as whether radiologic evidence could be suitable for contemporary evidence and be used to solve the posture difference of imaging test. This article summaries the domestic and foreign researches of individual identification using imaging data in the past 20 years and reviews the problems above.

[Neonatal sclerosing cholangitis caused by DCDC2 variations in two siblings and literature review].

Objective: To summarize and review the clinical and genetic features of neonatal sclerosing cholangitis (NSC) caused by DCDC2 variations. Methods: Whole exome sequencing was performed to identify DCDC2 variants in two Chinese siblings with NSC who were diagnosed in Children's Hospital of Fudan University in May 2017. Clinical, laboratory and genetic data of the two cases were summarized. Key words of "DCDC2" "neonatal sclerosing cholangitis" were searched in Chinese databases and PubMed for articles published until April 2018, and all the relevant literature were reviewed. Results: Patient 1 was a 3-year-and-2-month-old boy. He was admitted to our hospital due to cholestasis for 3 years. Laboratory findings showed elevated levels of gamma-glutamyl transpeptidase (161-1 092 U/L) and total cholesterol (5.4-7.7 mmol/L). Magnetic resonance cholangiopancreatography showed multiple dilations of intrahepatic bile ducts and bilateral hydronephrosis. Patient 2, the older brother of patient 1, was a 9-year-and-9-month-old boy. He was admitted to our hospital due to "cholestasis for 9 years" . CT angiography showed hydrocephalus and left internal carotid artery aneurysms with vascular malformations. A homozygous variant c.529dupA (NM_001195610) in DCDC2 gene was identified in patient 1 by whole exome sequencing. Patient 2 was a homozygote and his parents were heterozygotes with the variation. There has been 2 relevant articles published (Chinese 0, English 2), which reported 11 cases of DCDC2-related NSC in total. All the 13 patients, including the 2 cases reported here, had an onset of symptoms at 0 to 6 months of age. The most common clinical manifestation was cholestasis with high gamma-glutamyl transpeptidase levels, acholic stool, and progression to portal hypertension. Renal and neurological abnormalities were also frequently present. Hypercholesterolemia was observed in one case. Radiological findings revealed the characteristic strictures and dilatations of the intrahepatic and (or) extrahepatic biliary tree. Liver histological examination showed peripheral ductopenia, ductal plate malformation, fibrosis, and cirrhosis. Among the 13 patients, 10 patients required liver transplantation. A total of 7 types of DCDC2 variants were detected in 13 patients. Conclusions: DCDC2-related NSC is characterized by the onset of cholestasis with high gamma-glutamyl transpeptidase level and acholic stool in early infancy, which was likely to progress to cirrhosis in early childhood. Renal and neurological abnormalities are also frequently present.Cholangiography or magnetic resonance cholangiopancreatography show strictures and dilatations of the intrahepatic or (and) extrahepatic biliary tree. Identification of pathogenic DCDC2 variants would aid the diagnosis of NSC.

[Application of a modified tympanic membrane surgical knife with suction and tube device in myringotomy with ventilation tube placement].

Objective:To explore the efficacy of a modified tympanic membrane surgical knife with suction and tube device in myringotomy with ventilation tube placement for the treatment of secretory otitis media.Method:From June of 2014 to December of 2015, 87 cases of secretory otitis media were randomly divided into two groups: One group was treated by general approach to achieve tympanic membrane tube insertion, and another group with modified method. The total effective rate，the rate of tube detachment at 3 months postoperatively, the rate of scar formation or tympanic membrane atrophy, the operation time and the success rate of tube insertion for the first time in two groups were analyzed retrospectively. Result:There was no significantly difference between two groups about the total effective rate，the rate of tube detachment and the rate of scar formation or tympanic membrane atrophy（P>0.05）.However, the duration of operation in general method groupï¼»(11.4±4.3 min）］was significantly longer than that in modified method groupï¼»(8.1±3.6)minï¼½(t=5.412，P<0.05）.In addition, the success rate of tube insertion in general group（81.2%） was significantly lower than that in modified group（93.7%）(χ²=5.397，P<0.05）. Conclusion:The modified method contributed to shorten the duration of operation, improved the success rate of tube insertion and avoided the injury of tympanic membrane and external auditory canal caused by repeated operation.

Size-dependent electrical transport properties in Co nanocluster-assembled granular films.

A series of Co nanocluster-assembled films with cluster sizes ranging from 4.5 nm to 14.7 nm were prepared by the plasma-gas-condensation method. The size-dependent electrical transport properties were systematically investigated. Both of the longitudinal resistivity ([Formula: see text]) and saturated anomalous Hall resistivity ([Formula: see text]) continuously increased with the decrease of the cluster sizes (d). The [Formula: see text] firstly increased and then decreased with increasing the temperature for all samples, which could be well described by involving the thermally fluctuation-induced tunneling (FIT) process and scattering. The tunneling effect was verified to result in the invalidation of classical anomalous Hall effect (AHE) scaling relation. After deducting the contribution from tunneling effect to [Formula: see text], the AHE scaling relation between [Formula: see text] and the scattering resistivity ([Formula: see text]) by varying the temperature was reconstructed. The value of scaling exponent γ increased with increasing Co cluster sizes. The size dependence of γ might be qualitatively interpreted by the interface and surface-induced spin flip scattering. We also determined the scaling relation between [Formula: see text] and [Formula: see text] at 5 K by changing the Co cluster sizes, and a large value of γ = 3.6 was obtained which might be ascribed to the surface and interfacial scattering.

Multiple losses and transfers to the nucleus of two mitochondrial succinate dehydrogenase genes during angiosperm evolution.

Unlike in animals, the functional transfer of mitochondrial genes to the nucleus is an ongoing process in plants. All but one of the previously reported transfers in angiosperms involve ribosomal protein genes. Here we report frequent transfer of two respiratory genes, sdh3 and sdh4 (encoding subunits 3 and 4 of succinate dehydrogenase), and we also show that these genes are present and expressed in the mitochondria of diverse angiosperms. Southern hybridization surveys reveal that sdh3 and sdh4 have been lost from the mitochondrion about 40 and 19 times, respectively, among the 280 angiosperm genera examined. Transferred, functional copies of sdh3 and sdh4 were characterized from the nucleus in four and three angiosperm families, respectively. The mitochondrial targeting presequences of two sdh3 genes are derived from preexisting genes for anciently transferred mitochondrial proteins. On the basis of the unique presequences of the nuclear genes and the recent mitochondrial gene losses, we infer that each of the seven nuclear sdh3 and sdh4 genes was derived from a separate transfer to the nucleus. These results strengthen the hypothesis that angiosperms are experiencing a recent evolutionary surge of mitochondrial gene transfer to the nucleus and reveal that this surge includes certain respiratory genes in addition to ribosomal protein genes.

Unsaturated acyclic analogues of 2'-deoxyadenosine and thymidine containing fluorine: synthesis and biological activity.

The syntheses and biological activities of fluorobutynol 11 and (E)- and (Z)-fluorobutenols 8a,d and 9a,d are described. Alkylation of adenine with bromofluorobutyne 13a afforded intermediate 14 which was converted to fluorobutynol 11. Aldehyde 16a and (carbethoxyfluoromethyl)-triphenylphosphonium bromide furnished (E)- and (Z)-fluorobutenoates 19a and 20a accompanied by regioisomer 21a. A similar reaction of compound 16d afforded Z- and E-esters 19d and 20d. Reduction of the mixture of 19a and 20a with DIBALH gave (E)- and (Z)-fluoroalkenols 8a and 9a. Similarly, the Z-ester 19d gave (Z)-fluoroalkenol 9d. Both 19d and 20d were reduced with NaBH4 to give (Z)- and (E)-fluoroalkenols 9d and 8d. Hydrogenation of 19a and 20a afforded fluoro ester 23. A similar reduction of 8a and 9a led to fluoro alcohol 24 and the defluorinated product 25 which were separated by chromatography on a Bio-Rad AG 1-X2 (OH-) column. (Z)-Fluorobutenol 9a is a substrate for adenosine deaminase, whereas the E-isomer 8a is inert toward the enzyme. By contrast, analogue 8a inhibited the replication and cytopathic effect of HIV-1 in ATH8 cells with an IC50 of approximately 100 microM, but the Z-isomer 9a was inactive. This effect was accompanied by 36% cytotoxicity at 100 microM. Compounds 11 and 8d inhibited the growth of murine leukemia L1210 culture with IC50 = 89 and 60 microM, respectively.

(R)-(-)- and (S)-(+)-Synadenol: synthesis, absolute configuration, and enantioselectivity of antiviral effect.

Synthesis of (R)-(-)- and (S)-(+)-synadenol (1a and 2a, 95-96% ee) is described. Racemic synadenol (1a + 2a) was deaminated with adenosine deaminase to give (R)-(-)-synadenol (1a) and (S)-(+)-hypoxanthine derivative 5. Acetylation of the latter compound gave acetate 6. Reaction with N, N-dimethylchloromethyleneammonium chloride led to 6-chloropurine derivative 7. Ammonolysis furnished (S)-(+)-synadenol (2a). Absolute configuration of 1a was established by two methods: (i) synthesis from (R)-methylenecyclopropanecarboxylic acid (8) and (ii) X-ray diffraction of a single crystal of (-)-synadenol hydrochloride. Racemic methylenecyclopropanecarboxylic acid (10) was resolved by a modification of the described procedure. The R-enantiomer 8 was converted to ethyl ester 13 which was brominated to give vicinal dibromides 14. Reduction with diisobutylaluminum hydride then furnished alcohol 15 which was acetylated to the corresponding acetate 16. Alkylation-elimination procedure of adenine with 16 yielded acetates 17 and 18. Deprotection with ammonia afforded a mixture of Z- and E-isomers 1a and 19 of the R-configuration. Comparison with products 1a and 2a by chiral HPLC established the R-configuration of (-)-synadenol (1a). These results were confirmed by X-ray diffraction of a single crystal of (-)-synadenol hydrochloride. The latter forms a pseudosymmetric dimer with adenine-adenine base pairing in the lattice with the nucleobase in an anti-like conformation. Enantiomers 1a and 2a exhibit varied enantioselectivity toward different viruses. Both enantiomers are equipotent against human cytomegalovirus (HCMV) and varicella zoster virus (VZV). The S-enantiomer 2a is somewhat more effective than R-enantiomer 1a in herpes simplex virus 1 and 2 (HSV-1 and HSV-2) assays. By contrast, enantioselectivity of antiviral effect is reversed in Epstein-Barr virus (EBV) and human immunodeficiency virus type 1 (HIV-1) assays where the R-enantiomer 1a is preferred. In these assays, the S-enantiomer 2a is less effective (EBV) or devoid of activity (HIV-1).

(Z)- and (E)-2-((hydroxymethyl)cyclopropylidene)methyladenine and -guanine. New nucleoside analogues with a broad-spectrum antiviral activity.

New nucleoside analogues 14-17 based on a methylenecyclopropane structure were synthesized and evaluated for antiviral activity. Reaction of 2,3-dibromopropene (19) with adenine (18) led to bromoalkene 20, which was benzoylated to give N6,N6-dibenzoyl derivative 23. Attempts to convert 20 or 23 to bromocyclopropanes 21 and 22 by reaction with ethyl diazoacetate catalyzed by Rh2(OAc)4 were futile. By contrast, 2,3-dibromopropene (19) afforded smoothly (E)- and (Z)-dibromocyclopropane carboxylic esters 24 + 25. Alkylation of adenine (18) with 24 + 25 gave (E)- and (Z)-bromo derivatives 21 + 22. Base-catalyzed elimination of HBr resulted in the formation of (Z)- and (E)-methylenecyclopropanecarboxylic esters 26 + 27. More convenient one-pot alkylation-elimination of adenine (18) or 2-amino-6-chloropurine (30) with 24 + 25 afforded (Z)- and (E)-methylenecyclopropane derivatives 26 + 27 and 31 + 32. The Z-isomers were always predominant in these mixtures (Z/E approximately 2/1). Reduction of 26 + 27 and 31 + 32 with DIBALH afforded (Z)- and (E)-methylenecyclopropane alcohols 14 + 16 and 33 + 34. The latter were resolved directly by chromatography. Compounds 14 + 16 were converted to N6-(dimethylamino)methylene derivatives 28 and 29 which were separated and deprotected to give 14 and 16. Reaction of 33 and 34 with HCO2H led to guanine analogues 15 and 17. The 1H NMR spectra of the Z-analogues 14 and 15 are consistent with an anti-like conformation of the nucleobases. By contrast, 1H NMR and IR spectra of bromo ester 21 are indicative of syn-conformation of adenine. Several Z-(hydroxymethyl)methylenecyclopropanes exhibited in vitro antiviral activity in micromolar or submicromolar range against human and murine cytomegalovirus (HCMV and MCMV), Epstein-Barr virus (EBV), human herpes virus 6 (HHV-6), varicella zoster virus (VZV), and hepatitis B virus (HBV). Analogues 14, 15, and 33 were the most effective agents against HCMV (IC50 1-2.1, 0.04-2.1, and 0.8-5.6 microM), MCMV (IC50 2.1, 0.3, and 0.3 microM) and EBV in H-1 (IC50 0.2, 0.3, and 0.7 microM) and Daudi cells (IC50 3.2, 5.6, and 1.2 microM). Adenine analogue 14 was active against HBV (IC50 2 microM), VZV (IC50 2.5 microM), and HHV-6 (IC50 14 microM). Synadenol (14) and the E-isomer (16) were substrates of moderate efficiency for adenosine deaminase from calf intestine. The E-isomer 16 was more reactive than Z-isomer 14. The deamination of 14 effectively stopped at 50% conversion. Synadenol (14) was also deaminated by AMP deaminase from aspergillus sp.

Effective treatment of murine cytomegalovirus infections with methylenecyclopropane analogues of nucleosides.

A number of new nucleoside analogues with a Z- or E-methylenecyclopropane structure exhibited significant activity against human and murine cytomegaloviruses (HCMV, MCMV) in tissue culture that was generally comparable to, or greater than, 9-[(1-3-dihydroxy-2-propoxy)methyl]guanine (ganciclovir, GCV). Several of these analogues were chosen for further evaluation of therapeutic efficacy utilizing a MCMV infection. Intraperitoneal (i.p.) inoculation of 3-week-old Balb/c mice with 2.0 x 10(5) plaque forming units (pfu) of MCMV results in an acute, lethal infection with rapid virus replication in visceral and glandular tissue, thus, making it an ideal model for identifying compounds that have potential for use in humans. Synadenol (QYL-284A) and synguanol (QYL-438) were administered i.p. once daily for 5 days initiated 6, 24, or 48 h post-viral infection. Significant protection was demonstrated at 50 and 16.7 mg/kg compared to placebo, with efficacy comparable to GCV. When delivered orally once or twice daily at 100 mg/kg per day, QYL-438 was active, but less effective than GCV. In addition, 2-amino-6-methoxypurine analogue (QYL-941) was active at 60 mg/kg administered orally twice daily, comparable to GCV, while it's prodrug (QYL-972) was as effective as GCV at 40 mg/kg when delivered twice daily for 5 days. Additionally, analogue 2-amino-6-cyclopropylaminopurine (QYL-769) was found to be highly efficacious when given orally twice daily for 5 days. Mortality of 0% and 13% was observed at 60 and 20 mg/kg, respectively, which was similar to GCV. Oral treatment with QYL-769 or GCV reduced virus replication in target organs, but neither resulted in complete clearance of MCMV. These data indicate that these new analogues have activity comparable to GCV when given orally to mice and should be evaluated further to assess their potential for use in humans.

Synthesis and antiviral activity of phosphoralaninate derivatives of methylenecyclopropane analogues of nucleosides.

Phenylmethylphosphoro-L-alaninate prodrugs of antiviral Z-methylenecyclopropane nucleoside analogues and their inactive E-isomers were synthesized and evaluated for their antiviral activity against HCMV, HSV-1, HSV-2, HHV-6, EBV, VZV, HIV-1 and HBV. The adenine Z-analogue was a potent inhibitor of all these viruses but it displayed cellular toxicity. The guanine Z-derivative was active against HCMV, HBV, EBV and VZV and it was not cytotoxic. The 2,6-diaminopurine analogue was the most potent against HIV-1 and HBV and somewhat less against HHV-6, HCMV, EBV and VZV in a non-cytotoxic concentration range. The 2-amino-6-cyclopropylamino and 2-amino-6-methoxypurine prodrugs were also more active than parent analogues against several viruses but with a less favorable cytotoxicity profile. In the E-series of analogues, adenine derivative was active against HIV-1, HBV and EBV, and it was non-cytotoxic. The guanine analogue exhibited a significant effect only against HBV. The 2,6-diaminopurine E-analogue was inactive with the exception of a single EBV assay. The 2-amino-6-methoxypurine Z-methylenecyclopropane nucleoside analogue was an effective inhibitor of HCMV, MCMV and EBV. The 2,6-diaminopurine Z-prodrug seems to be the best candidate for further development.

(Z)- and (E)-2-(hydroxymethylcyclopropylidene)-methylpurines and pyrimidines as antiviral agents.

Several Z- and E-methylenecyclopropane nucleoside analogues were synthesized and tested for antiviral activity in vitro against human and murine cytomegalovirus (HCMV, MCMV), Epstein-Barr virus (EBV), varicella zoster virus (VZV), hepatitis B virus (HBV), herpes simplex virus types 1 and 2 (HSV-1, HSV-2), human herpesvirus 6 (HHV-6) and human immunodeficiency virus type 1 (HIV-1). The Z-2-amino-6-cyclopropylaminopurine analogue was the most effective agent against HCMV (EC50 or EC90 0.4-2 microM) followed by syncytol and the Z-2,6-diaminopurine analogues (EC50 or EC90 3.4-29 and 11-24 microM, respectively). The latter compound was also a strong inhibitor of MCMV (EC50 0.6 microM). Syncytol was the most potent against EBV (EC50 < 0.41 and 2.5 microM) followed by the Z-2,6-diaminopurine (EC50 1.5 and 6.9 microM) and the Z-2-amino-6-cyclopropyl-aminopurine derivative (EC50 11.8 microM). Syncytol was also most effective against VZV (EC50 3.6 microM). Activity against HSV-1, HSV-2 and HHV-6 was generally lower; synthymol had an EC50 of 2 microM against HSV-1 (ELISA) and 1.3 microM against EBV in Daudi cells but was inactive in other assays. The 2-amino-6-cyclopropylamino analogue displayed EC50 values between 215 and > 74 microM in HSV-1 and HSV-2 assays. 2-Amino-6-cyclopropylaminopurine and 2,6-diaminopurine derivatives were effective against HBV (EC50 2 and 10 microM, respectively), whereas none of the analogues inhibited HIV-1 at a higher virus load. Syncytol and the E isomer were equipotent against EBV in Daudi cells but the E isomer was much less effective in DNA hybridization assays. The E-2,6-diaminopurine analogue and E isomer of synthymol were devoid of antiviral activity.

Synthesis and enantioselectivity of the antiviral effects of (R,Z)-,(S,Z)-methylenecyclopropane analogues of purine nucleosides and phosphoralaninate prodrugs: influence of heterocyclic base, type of virus and host cells.

A series of R and S enantiomers of 2-aminopurine methylenecyclopropane analogues of nucleosides was synthesized. Two diastereoisomeric lipophilic phosphate prodrugs derived from R and S enantiomers of 2,6-diaminopurine analogue were also prepared. Enantioselectivity (diastereoselectivity in case of prodrugs) of in vitro antiviral effects was investigated with human and murine cytomegalovirus (HCMV and MCMV, respectively), herpes simplex virus types 1 and 2 (HSV-1 and HSV-2, respectively), human immunodeficiency virus type 1 (HIV-1), hepatitis B virus (HBV), Epstein-Barr virus (EBV) and varicella zoster virus (VZV). Strong differences in enantioselectivity were found between the R and S enantiomers of adenine analogue and enantiomeric 2-aminopurine analogues. Thus, the enantiomers of adenine analogue were equipotent against HCMV but not MCMV, where the S enantiomer is strongly preferred. The same S preference was found throughout the 2-aminopurine series for both HCMV and MCMV. In contrast, R-synadenol in HIV-1 assays was the best agent, whereas the S enantiomers of moderately effective 2-amino-6-cyclopropylamino and 2-amino-6-methoxypurine analogues were preferred. Little enantiomeric preference was found for R and S enantiomers of synadenol and the corresponding enantiomers of 2,6-diaminopurine analogue against HBV. A mixed pattern of enantioselectivity was observed for EBV depending on the type of host cells and assay. Against VZV, the R and S enantiomers of adenine analogue were equipotent or almost equipotent, but throughout the series of 2-aminopurine analogues a distinct preference for the S enantiomers was found. The stereoselectivity pattern of both diastereoisomeric prodrugs mostly followed enantioselectivity of the parent analogues. The varying enantioselectivities in the series of purine methylenecyclopropane analogues are probably a consequence of differences in the mechanisms of action in different virus/host cell systems.

Treatment of coke-plant wastewater by biofilm systems for removal of organic compounds and nitrogen.

Coke-plant wastewater was treated by an anaerobic-anoxic-aerobic (A(1)-A(2)-O) biofilm system and an anoxic-aerobic (A/O) biofilm system, respectively. At same or similar levels of hydraulic retention time (HRT), the two systems had almost identical chemical oxygen demand (COD) and NH(3) removals, but a different organic-N removal. Set-up of an acidogenic stage benefited for the removal of organic-N and the A(1)-A(2)-O system was more useful for total nitrogen removal than the A-O system. HRT did not have a substantial effect on the COD and NH(3)-N removal efficiencies, but considerably influenced the organic-N removal and distribution of oxidized nitrogen in the final effluent. The GC/MS analysis demonstrated that some refractory compounds were decomposed at the acidogenic stage and resulted in the production of some intermediates, which were more readily degraded in the subsequent aerobic stage. Hence, the A(1)-A(2)-O system had better effluent quality than the A-O system in terms of effluent composition.

Phylogenetic distribution and evolution of mycorrhizas in land plants.

A survey of 659 papers mostly published since 1987 was conducted to compile a checklist of mycorrhizal occurrence among 3,617 species (263 families) of land plants. A plant phylogeny was then used to map the mycorrhizal information to examine evolutionary patterns. Several findings from this survey enhance our understanding of the roles of mycorrhizas in the origin and subsequent diversification of land plants. First, 80 and 92% of surveyed land plant species and families are mycorrhizal. Second, arbuscular mycorrhiza (AM) is the predominant and ancestral type of mycorrhiza in land plants. Its occurrence in a vast majority of land plants and early-diverging lineages of liverworts suggests that the origin of AM probably coincided with the origin of land plants. Third, ectomycorrhiza (ECM) and its derived types independently evolved from AM many times through parallel evolution. Coevolution between plant and fungal partners in ECM and its derived types has probably contributed to diversification of both plant hosts and fungal symbionts. Fourth, mycoheterotrophy and loss of the mycorrhizal condition also evolved many times independently in land plants through parallel evolution.