Fine mapping of Hyplip1 and the human homolog, a potential locus for FCHL

Familial combined hyperlipidemia (FCHL) is a common genetic dyslipidemia predisposing to premature coronary heart disease (CHD). We previously identified a locus for FCHL on human Chromosome (Chr) 1q21-q23 in 31 Finnish FCHL families. We also mapped a gene for combined hyperlipidemia (Hyplip1) to a potentially orthologous region of mouse Chr 3 in the HcB-19/Dem mouse model of FCHL. The human FCHL locus was, however, originally mapped about 5 Mb telomeric to the synteny border, the centromeric part of which is homologous to mouse Chr 3 and the telomeric part to mouse Chr 1. To further localize the human Hyplip1 homolog and estimate its distance from the peak linkage markers, we fine-mapped the Hyplip1 locus and defined the borders of the region of conserved synteny between human and mouse. This involved establishing a physical map of a bacterial artificial chromosome (BAC) contig across the Hyplip1 locus and hybridizing a set of BACs to both human and mouse chromosomes by fluorescence in situ hybridization (FISH). We narrowed the location of the mouse Hyplip1 gene to a 1.5-cM region that is homologous only with human 1q21 and within approximately 5-10 Mb of the peak marker for linkage to FCHL. FCHL is a complex disorder and this distance may, thus, reflect the well-known problems hampering the mapping of complex disorders. Further studies identifying and sequencing the Hyplip1 gene will show whether the same gene predisposes to hyperlipidemia in human and mouse.

Differential mechanisms mediating descending pain controls for antinociception induced by supraspinally administered endomorphin-1 and endomorphin-2 in the mouse

We have previously demonstrated that both endomorphin-1 and endomorphin-2 produce their antinociception by the stimulation of mu-opioid receptors. However, the antinociception induced by endomorphin-2 contains an additional component, which is mediated by the release of dynorphin A (1-17) acting on kappa-opioid receptors. These studies were done to determine whether the antinociception induced by endomorphin-1 and endomorphin-2 given supraspinally was mediated by the activation of different descending pain control pathways in the mouse. Specific receptor antagonists or antisera against endogenous opioid peptides were injected intrathecally to block the receptors or bind the released endogenous opioid peptides, and endomorphin-1 or endomorphin-2 was then administered i.c.v. to activate the descending pain control systems to produce antinociception. The tail-flick response was used as antinociceptive test. The blockade of the alpha(2)-adrenoceptors and 5-hydroxytryptamine receptors in the spinal cord by i.t. injection of yohimbine and methysergide, respectively, inhibited the antinociception induced by i.c.v.-administered endomorphin-1 and endomorphin-2. However, the antinociception induced by endomorphin-2 was inhibited by i.t. pretreatment with delta(2)-opioid receptor antagonist naltriben or kappa-opioid receptor antagonist nor-binaltorphimine, but not by the mu-opioid receptor antagonist D-Phe-Cys-Tyr-D-Try-Orn-Thr-Pen-Thr-NH(2) or the delta(1)-opioid receptor antagonist 7-benzylidene naltrexamine. Intrathecal pretreatment with antiserum against Met-enkephalin attenuated the antinociception induced by i.c.v.-administered endomorphin-2, but not endomorphin-1. Furthermore, i.t. pretreatment with antiserum against dynorphin A (1-17) also inhibited the antinociception induced by i.c.v.-administered endomorphin-2, but not endomorphin-1. Intrathecal pretreatment with antiserum against Leu-enkephalin or beta-endorphin did not inhibit i.c.v.-administered endomorphin-1- or endomorphin-2-induced antinociception. The results indicate that, like other opioid micro-receptor agonists, morphine, and [D-Ala(2), N-Me-Phe(4), Gly(5)-ol]-enkephalin, endomorphin-1 and endomorphin-2 given i.c.v. produce antinociception by activating spinipetal noradrenergic and serotonergic pathways for producing antinociception. However, the antinociception induced by endomorphin-2 given i.c.v. also contains other components, which are mediated by the release of Met-enkephalin and dynorphin A (1-17) acting on opioid delta(2)- and kappa-receptors, respectively, in the spinal cord.

[Separation and identification of polyclonal antibodies against type II fimbriae of actinomyces viscosus 5951]

OBJECTIVE

This study was aimed to prepare the polyclonal antibodies against type II fimbriae of actinomyces viscosus 5951.

METHODS

Purified type II fimbriae of actinomyces viscosus 5951 were obtained by physical and chemical ways. Then antibodies against type II fimbriae were prepared through immunity of poly ways and tested by double immunodiffusion.

RESULTS

The molecular quality of type II fimbriae was 34ku.Concentration of antibodies against type II fimbriae reached 1:64 after immunity of poly ways.

CONCLUSION

The molecular quality of type II fimbriae was 34ku.The titre of the antibodies was 1:64, and had mild cross reaction with type I fimbriae.

Motional dressed states in a bose-einstein condensate: superfluidity at supersonic speed

We present an exact analytic solution of a nonlinear Schrodinger field interacting with a moving potential (obstacle) at supersonic speed. We discover conditions under which the field can form a stable shape-invariant structure localized around the obstacle-a dressing effect that protects the field against excitations by the obstacle. Such an effect demonstrates the existence of frictionless motion beyond the conventionally defined critical velocity.

An outbreak of plague including cases with probable pneumonic infection, Ecuador, 1998

During February and March of 1998, 12 sudden deaths were reported among residents of a high-Andean community in Ecuador. All 12 fatalities were members of the same extended family and some had apparent exposure to sick guinea-pigs. Following an initial investigation by public health officials, an additional death was reported in a nearby community in April, also associated with exposure to sick guinea-pigs. Blood samples from humans, dogs, and a rodent were tested for antibody to the F1 antigen of Yersinia pestis by passive haemagglutination assay. Tissue from rodents was subjected to direct fluorescent antibody staining using fluorescein-labelled monoclonal antibody to Y. pestis F1 antigen. Formalin-fixed specimens from the 2 autopsies were evaluated using a 2-step alkaline phosphatase immunoassay with a monoclonal antibody to Y. pestis F1 antigen, and tissues that had not been embedded in paraffin were tested for the presence of DNA encoding the F1 structural antigen by polymerase chain reaction. Serological evaluation of close contacts of the fatalities revealed positive titres to F1 antigen of Y. pestis, the aetiological agent of plague, in 3 contacts from the first community and 1 from the second. Immunohistochemical staining of tissues collected from 2 of the fatalities provided evidence that both had pneumonic plague. Five of 14 dogs found in the communities were seropositive for plague antibody, providing evidence of a recent epizootic plague in the area.

Three clusters of ciguatera poisoning: clinical manifestations and public health implications

Between July 1997 and August 1998 we investigated three clusters (26 cases) of ciguatera poisoning in the inner Sydney area. Tropical reef fish were implicated in each cluster. Most of those affected had musculoskeletal, neurological and gastrointestinal symptoms. The clusters raise questions about the need for rapid diagnosis and enhanced surveillance mechanisms, the regulation of fish supply, and the lack of testing facilities for ciguatera toxin.

Spectroscopic characterization of Co(II)-, Ni(II)-, and Cd(II)-substituted wild-type and non-native retroviral-type zinc finger peptides

The nucleocapsid protein (NCP) from Mason-Pfizer monkey virus (MPMV) contains two evolutionary invariant Cys-X2-Cys-X4-His-X4-Cys retroviral-type zinc finger structures, where the Cys and His residues provide ligands to a tetrahedrally coordinated Zn(II) ion. The N-terminal zinc finger (F1) of NCP from MPMV contains an immediately contiguous Cys in the -1 position relative to the start of this conserved motif: Cys-Cys-X2-Cys-X4-His-X4-Cys. Metal complexes of 18-amino acid peptides which model the native zinc finger sequence, SER-Cys-X2-Cys-X4-His-X4-Cys (F1-SC), and non-native Cys-SER-X2-Cys-X4-His-X4-Cys (F1-CS) and SER-SER-X2-Cys-X4-His-X4-Cys (F1-SS) sequences have been spectroscopically characterized and compared to the native two-zinc-finger protein fragment, MPMV NCP 21-80. All Co(II)-substituted peptide complexes adopt tetrahedral ligand geometries and have S- -->Co(II) ligand-to-metal charge-transfer (LMCT) transition intensities consistent with three Co(II)-S bonds for F1-SC and F1-CS. The non-native F1-CS peptide binds Co(II) with KCo= 1.5 x 10(6) M(-1), comparable to that of the native complex, and approximately 100-fold tighter than F1-SS. Like the Co(II) derivative, the absorption spectrum of Ni(II)-substituted NCP 21-80 is most consistent with tetrahedral Ni(II) complexes with multiple thiolate donors. In contrast, Ni(II) complexes of F1-SC and F1-CS exhibit a single absorption band in the 400-550 nm region (epsilon approximately 200-300 M(-1) cm (-1), distinct in the two complexes, assignable to a degenerate d-d transition envelope characteristic of non-native square-planar coordination geometry, and an intense LMCT transition in the UV (epsilon255 approximately 14,000 M(-1) cm(-1)). Cd(II) complexes have intense absorption in the UV (lambda(max)=233nm), with absolute intensities consistent with approximately 5000 M(-1) cm(-1) per Cd(II)-S bond. 113Cd NMR spectroscopy of 113Cd MPMV NCP gives delta=649 ppm, consistent with S3N coordination. Co(II) and Cd(II) complexes of non-native F1-CS peptides are more sensitive to oxidation by O2, relative to F1-SC, suggestive of a higher lability in the non-native chelate. The implications of these findings for the evolutionary conservation of this motif are discussed.

Genetic dissection of tomato bushy stunt virus p19-protein-mediated host-dependent symptom induction and systemic invasion

The plus-sense single-stranded RNA of tomato bushy stunt virus (TBSV) encodes a 19-kDa protein, which is translated from a 3' proximal open reading frame (p19) that is entirely nested within the cell-to-cell movement gene (p22). Expression of the cytosolic p19-protein induces either a systemic lethal collapse in Nicotiana benthamiana and N. clevelandii, or necrotic local lesions on resistant N. tabacum. In spinach, the p19-protein is required at high abundance for efficient systemic invasion. This study aimed to determine whether these seemingly different host-dependent biological activities are governed by the same or separate regions on the 172 amino acid p19-protein. For this purpose, codons for charged amino acids predicted to be exposed on the surface of the polypeptide and presumably available for host-specific interactions, were targeted for mutagenesis. A total of 12 mutants were generated, which had no deficiencies in replication or cell-to-cell movement, and substitution of amino acids at the extreme N-terminal end or within the carboxyl 70 amino acids failed to cause a noticeable biological effect on plants. However, mutations dispersed between positions 43 and 85 on the N-terminal half prevented the onset of a systemic lethal necrosis on N. benthamiana and N. clevelandii. With one exception, the same mutants elicited mostly chlorotic, rather than necrotic, local lesions on N. tabacum. Mutations in the central region, which substituted Arg with Gly at positions 72 or 75-78, impaired the ability of TBSV to systemically invade spinach plants. However, substitution with Ala instead of Gly at position 72 had minimal effects on systemic spread in spinach, suggesting the possible influence of protein structure effects. The implications are that regions on the N-terminal portion of the p19-protein mediate interactions in a host-dependent manner and that a central region is required for all activities either by a direct effect of the amino acids or through maintenance of structural integrity.

MRE-Binding transcription factor-1: weak zinc-binding finger domains 5 and 6 modulate the structure, affinity, and specificity of the metal-response element complex

MRE-binding transcription factor-1 (MTF-1) contains six Cys(2)-His(2) zinc finger sequences, and it has been suggested that the zinc finger domain itself may function as a zinc sensor in zinc-activated expression of metallothioneins (MTs). Previous work has shown that a subset ( approximately 3-4) of the zinc fingers in MTF-zf play a structural role in folding and high-affinity metal-response element (MREd) binding, while one or more other fingers have properties consistent with a metalloregulatory role (weak zinc binding affinity in the absence of DNA). We show here that zinc fingers 5 and 6 correspond to the weak zinc-binding fingers in MTF-zf. Limited trypsinolysis of a Zn(6)-MTF-zf:MREd complex gives rise to a highly protease-resistant core fragment corresponding to amino acids 137-260 or N-terminal zinc fingers 1-4 of MTF-zf. Characterization of a collection of broken-finger (His --> Asn) and missing-finger mutants of MTF-zf reveals that deletion of zinc fingers 5 and 6 to create MTF-zf14 attenuates MREd binding affinity ( approximately 20-fold), while deletion of fingers 4-6 (MTF-zf13) results in a further 20-fold reduction of binding affinity with a nearly complete loss of specificity. Circular dichroism studies reveal that the binding of MTF-zf to the MREd induces a dramatic alteration of the structure of the MREd from a B-form to a double-helical conformation with A-like features. Formation of stoichiometric complexes with MTF-zf14, H279N (Deltazf5) MTF-zf, and MTF-zf13 induces comparatively less A-like structure. Steady-state fluorescence resonance energy transfer (FRET) spectroscopy has been used to globally define the orientation of the multifinger MTF-zf on the MREd. These experiments suggest that fingers 1-4 are oriented on the highly conserved TGCRCnC side of the MREd with fingers 5-6 bound at or near the gGCCc sequence. These findings are consistent with a model in which the N-terminal zinc fingers in MTF-zf are required for high affinity and specific binding to the consensus TGCRCnC core in a way which is subjected to structural and allosteric modulation by the weak zinc-binding C-terminal zinc fingers.

Isolation and structure of SCH 351633: a novel hepatitis C virus (HCV) NS3 protease inhibitor from the fungus Penicillium griseofulvum

A new hepatitis C virus (HCV) protease inhibitor designated as Sch 351633 (1) was isolated from the fungus, Penicillium griseofulvum. Structure elucidation of 1 was accomplished by analysis of spectroscopic data, which determined compound 1 to be a bicyclic hemiketal lactone. Compound 1 exhibited inhibitory activity in the HCV protease assay with an IC50 value of 3.8 microg/mL.

PCR detection of Yersinia pestis in fleas: comparison with mouse inoculation

The "gold standard" for identifying Yersinia pestis-infected fleas has been inoculation of mice with pooled flea material. Inoculated mice are monitored for 21 days, and those that die are further analyzed for Y. pestis infection by fluorescent-antibody assay and/or culture. PCR may provide a more rapid and sensitive alternative for identifying Y. pestis in fleas. To compare these assays, samples were prepared from 381 field-collected fleas. Each flea was analyzed individually by both PCR and mouse inoculation. Sixty of the 381 flea samples were positive for Y. pestis by PCR; 48 of these PCR-positive samples caused death in mice (80.0% agreement). None of the 321 PCR-negative samples caused death. Among the 12 mice that survived inoculation with PCR-positive samples, 10 were later demonstrated by serology or culture to have been infected with Y. pestis. This suggests that death of inoculated mice is less reliable than PCR as an indicator of the presence of Y. pestis in flea samples. Mouse inoculation assays produce results that are comparable to PCR only when surviving as well as dead mice are analyzed for infection. The rapidity and sensitivity (10 to 100 CFU of Y. pestis) of PCR suggest that it could serve as a useful alternative to mouse inoculation for routine plague surveillance and outbreak investigations.

Immature thymocytes employ distinct signaling pathways for allelic exclusion versus differentiation and expansion

T cell receptor (TCR) beta chain allelic exclusion occurs at the thymocyte CD4- 8- (double-negative, or DN) to CD4+ 8+ (double-positive, or DP) transition, concurrently with differentiation and cellular expansion, and is imposed by a negative feedback loop in which a product of the first rearranged TCRbeta allele arrests further recombination in the TCRbeta locus. All of the major events associated with the development of DP cells can be induced by the introduction of TCRbeta or activated Lck transgenes. Here, we present evidence that the signaling pathways that promote thymocyte differentiation and expansion of RAG-deficient DN cells but not those that suppress rearrangements of endogenous TCRbeta genes in normal DN cells are engaged by activated Ras. We propose that TCRbeta allelic exclusion is mediated by effector pathways downstream of Lck but independent of Ras.

Phenolic aporphine-benzylisoquinoline alkaloids from Thalictrum faberi

From the roots of Thalictrum faberi, six new phenolic aporphine-benzylisoquinoline alkaloids, 3-hydroxy-6'-desmethyl-9-O-methylthalifaboramine (1), 3-hydroxythalifaboramine (2), 6'-desmethylthalifaboramine (3); 3,5'-dihydroxythalifaboramine (4), 5'-hydroxythalifaboramine (5) and 3-hydroxy-6'-desmethylthalifaboramine (6) were isolated. Their structures were established through the use of one- and two-dimensional NMR techniques. All of the tested alkaloids showed potent cytotoxic and antimalarial activities.

Nystatin prophylaxis: its inability to prevent fungal peritonitis in patients on continuous ambulatory peritoneal dialysis

OBJECTIVE

To evaluate the potential effectiveness of nystatin as prophylaxis for fungal peritonitis (FP) in patients on continuous ambulatory peritoneal dialysis (CAPD).

DESIGN

This historically controlled study was designed to investigate the effectiveness of nystatin in the prevention of FP. For this purpose we compared the incidence of FP among 240 (new and prevalent) CAPD patients between January 1996 and November 1996 (period A) with its incidence in 240 new and prevalent CAPD patients in our program between January 1997 and November 1997 (period B) when nystatin prophylaxis was used. There were 2400 patient-months in each period. Nystatin (500,000 IU four times per day), was given orally at the beginning of other antibiotic therapy (usually for peritonitis) and continued for 5 days after the end of the antibiotic therapy.

RESULTS

During period A, 133 peritonitis episodes were recorded, and during period B, 99 episodes were recorded. Six episodes of FP were identified in over 2400 patient-months of period A, and 12 in over 2400 patient-months of period B. This difference was not statistically significant. Three episodes of antibiotic-related FP were seen in period A, and four in period B. The remaining episodes arose de novo, that is, unrelated to the use of antibiotics. We observed no side effects for nystatin.

CONCLUSION

In CAPD patients the use of nystatin, a nonabsorbable antifungal agent, as prophylaxis in every instance of peritonitis or other indications for antibiotics, did not lower the incidence of fungal peritonitis.

Pregnancy outcome following maternal organic solvent exposure: a meta-analysis of epidemiologic studies

BACKGROUND

Evidence of fetal damage or demise from occupational organic solvent levels that are not toxic to the pregnant woman is inconsistent in the medical literature. The risk for major malformations and spontaneous abortion from maternal inhalation of organic solvent exposure during pregnancy was summarized using meta-analysis.

METHODS

Medline, Toxline, and Dissertation Abstracts databases were searched to locate all research papers published in any language from 1996 to 1994. Included were studies that were case-control or cohort in design and indicated first trimester (or up to 20 weeks gestation for spontaneous abortion) maternal solvent exposure. A summary odds ratio (ORs) with 95% confidence intervals (CI) was calculated from research results combined by the Mantel-Haenszel method.

RESULTS

In total, 559 studies were obtained from the literature search. Five studies for each outcome of interest qualified for inclusion in the analysis. The ORs for major malformations from five studies (n = 7,036 patients) was 1.64 (CI 1.16-2.30) and for spontaneous abortion from five studies (n = 2,899 patients) was 1.25 (CI 0.99-1.58).

CONCLUSIONS

Maternal occupational exposure to organic solvents is associated with a tendency toward an increased risk for spontaneous abortion and additional studies may affect the trend. There is a statistically significant association with major malformations which warrants further investigation.

The futility of pretransplant coronary bypass grafting in asymptomatic patients on peritoneal dialysis

OBJECTIVE

To evaluate the validity of recommending coronary artery bypass grafting (CABG) in preparation for renal transplantation in asymptomatic peritoneal dialysis (PD) patients with evidence of reversible myocardial ischemia.

DESIGN

Retrospective review in a single PD unit.

PARTICIPANTS

Ten asymptomatic PD patients who underwent CABG to be placed on the transplant list comprised the study group. Ten age-, sex-, and disease-matched PD patients who did not receive CABG were used as a comparison group.

MEASUREMENTS

Clinical outcome from 1990 to the present.

RESULTS

Only 1 patient in the study group has received a transplant. Seven patients (70%) have died or have been removed from the list because of comorbid illness. Only 2 patients are still on the waiting list.

CONCLUSION

As a result of the long waiting time for cadaveric renal transplant and the high risk of interim development of comorbid disease, only a minority of patients come to transplantation. The presence of coronary disease is likely a surrogate for more generalized cardiac and vascular disease in this population. In light of these findings, the policy of prophylactic revascularization in asymptomatic dialysis patients in preparation for renal transplantation needs to be reconsidered.

The effect of blood in the oral cavity on breath alcohol analysis

The theory that blood (containing alcohol) present in the oral cavity may falsely increase breath analysis recently led to a successful appeal against a drink driving conviction. Subjects who had previously consumed vodka (37.2% alc/vol), at 30 ml/10 kg and reached a BAC (blood alcohol concentration) of between 0.05 and 0.10% were then given four oral solutions consisting of a control (distilled water), and 0.05, 0.10 and 0.15% aqueous alcohol (ethanol) solutions, administered in coded form. A four-way cross-over, blind, randomized assay was conducted with the solutions, with breath analyses conducted in the presence or absence of solution in the mouth. The first trial group (n = 18) received 2 ml of solution, and we found that the simulated 0.15, 0.10 and 0.05% alcohol solutions in the mouth produced BAC reading increases of 0.0088 +/- 0.0014, 0.0062 +/- 0.0008 and 0.0055 +/- 0.0010% respectively (p < 0.001). The second trial group (n = 20) received 1 ml of solution and produced BAC reading increases of 0.0047 +/- 0.0011 (p < 0.001), 0.0023 +/- 0.0008 (p < 0.01) and 0.0020 +/- 0.0006% (p < 0.05) respectively. In conclusion, these studies indicate that small volumes of blood (containing alcohol) in the mouth would not have a practical effect on breath analysis readings.

Turnover of thrombomodulin at the cell surface occurs at a similar rate to receptors that are not actively internalized

Loss of thrombomodulin (TM) from the endothelial cell surface is thought to contribute to thrombosis encountered in malignant and inflammatory disease. Internalization or endocytosis of TM from the cell surface has been proposed to be one mechanism by which TM levels are reduced. Previous work has led to a view that TM is rapidly internalized using a non-conventional pathway, under the direction of a signal motif in its extracellular domain. This is contrary to the clathrin-dependent route taken by most rapidly internalized receptors that possess signals in their cytoplasmic domains. However the internalization rate of TM has never been directly compared to known internalizing or non-internalizing molecules. Here we show that the rate and amount of uptake of TM (5-10% per hour) is indistinguishable from the non-internalizing influenza virus haemagglutinin (HA), and is considerably less than the actively internalizing low density lipoprotein receptor, which reaches a steady state of approximately 50% internalized in 15 min. The low level rate of TM and HA internalization observed is comparable to the rate of normal plasma membrane turnover. Furthermore, this uptake of TM does not require a signal in its extracellular domain.

Neurokinin receptor inhibitors: fermentation, isolation, physico-chemical properties, structure and biological activity

Seven neurokinin (NK) receptor inhibitors SCH 60059 (1), SCH 60065 (2), SCH 64879 (3), SCH 60061 (4), SCH 60063 (5), SCH 60057 (7), and SCH 64878 (9) and two uncharacterized components 6 and 8, were isolated from the fermentation broth of a fungus taxonomically classified as an Acremonium sp. These compounds were isolated from the fermentation broth by ethyl acetate extraction. Purification and separation of the individual compounds were achieved by NK1 and NK2 assay-guided fractionation using gel filtration, reverse phase chromatography and HPLC. The NK active compounds were identified to be a family of polyhydroxy isoprenoid derivatives, including glycosylated members, by spectroscopic and degradation studies. Compounds 1 approximately 5 and 7 contain nine isoprene units connected in head to tail fashion and compound 9 contains fifteen isoprene units connected in a similar manner. All these compounds showed dual inhibition in NK1 and NK2 assays with IC50 values ranging from 2.5 approximately 11 microM in the NK1 assay and 6.8 approximately 16 microM in the NK2 assay.

Relationship of short-term verbal memory to the need for hyperbaric oxygen treatment after carbon monoxide poisoning

It has long been known that carbon monoxide (CO) poisoning has a spectrum of effects on cognitive functioning, including memory, perception, and attention. The current study reports the investigation of the effects of CO poisoning on short-term verbal memory, both rote and context aided. Impairment was measured before and after hyperbaric oxygen (HBO) treatment. Twenty-six patients who had been admitted for emergency treatment after exposure to significant CO poisoning were tested using a measure of short-term recall for word lists with no or varying degrees of internal context-aided structure. Impairment of context-aided memory (but not rote memory) has been previously reported to be associated with low relative frontal volume in psychiatric patients. Carbon monoxide poisoning was significantly associated with impairment of context-aided memory, with the degree of pretreatment impairment predicting the number HBO treatments judged to be necessary on the basis of clinical monitoring of the patient. In patients with poisoning of moderate severity, pretreatment performance in context-aided memory improved after the first HBO treatment. The implications of these findings for the effects of CO poisoning on frontal area function are discussed. The memory measure used in this study appears to have considerable potential usefulness in the clinical assessment of the severity of CO poisoning in patients treated in an emergency setting.

Two separate regions in the genome of the tobacco etch virus contain determinants of the wilting response of Tabasco pepper

Infection of Tabasco pepper by the tobacco etch virus (TEV) typically causes wilting associated with root necrosis. However, a strain of TEV, designated TEV nonwilting (TEV NW), is able to infect Tabasco pepper plants but does not cause wilting. In order to locate the genetic determinants responsible for the wilting response, a full-length cDNA clone of TEV NW from which infectious transcripts can be derived was made. A number of chimeric constructs were prepared by substituting cDNA fragments between TEV HAT (which causes wilting) and TEV NW clones. This approach was used to identify two wilting determinants in TEV HAT: one encompasses the 3' one-third of the P3 encoding region; the other spans the 3' end of the CI, the 6-kDa protein, and the 5' end of the VPg-NIa coding regions. Substitutions of both these TEV NW fragments into TEV HAT resulted in infection but not wilting of Tabasco pepper, while the replacement of either of the fragments alone did not alter the wilting response. This indicates that both TEV NW regions contain determinants necessary but not sufficient to alter the wilting response and that both must be present in order to avoid the wilting response. There was no difference between the in vitro transcription-translation products derived from constructs containing these regions from TEV HAT and TEV NW.

Sch 54445: a new polycyclic xanthone with highly potent antifungal activity produced by Actinoplanes sp

A novel antifungal agent, Sch 54445, was isolated from the fermentation broth of an Actinoplanes species. Sch 54445 was identified as a polycyclic xanthone related to the albofungin family of compounds on the basis of analyses of spectroscopic data. As a broad-spectrum antifungal agent, Sch 54445 exhibits highly potent activities against various yeasts and dermatophytes with MIC values approximately 0.00038 microgram/mL.