Accumulation of chlorpyrifos on residential surfaces and toys accessible to children

Quantitative examination of major pathways and routes of exposure to pesticides is essential for determining human risk. The current study was conducted in two apartments and examines the accumulation of the pesticide chlorpyrifos in childrens' toys after the time suggested for reentry after application. It has been established for the first time that a semivolatile pesticide will accumulate on and in toys and other sorbant surfaces in a home via a two-phase physical process that continues for at least 2 weeks postapplication. A summation of the above for a 3-6-year-old child yielded an estimated nondietary total dose of 208 microg/kg/day. Potential exposure from the inhalation pathway was negligible, while dermal and nondietary oral doses from playing with toys contributed to 39 and 61% of the total dose, respectively. If children with high frequency mouthing behavior are considered as candidates for acute exposure to chlorpyrifos residues, the estimated acute dose could be as high as 356 microg/kg/day. Routine reapplication of pesticides could lead to continued accumulation in toys and other sorbant surfaces, e.g., pillows, with large sorbant reservoirs, which can become a long-term source of exposure to a child. Estimates of a child's nondietary exposure to chlorpyrifos associated with toys and other sorbant surfaces for a period of 1 week following application appear to be of public health concern, and studies of actual childhood exposure from this pathway are warranted in the home environment. The above information should be used to determine if current procedures for postapplication reentry are sufficient and to evaluate the need for procedures to store frequently used household toys, pillows, and other sorbant objects during insecticidal application.

Systematic review and economic modelling of the effectiveness and cost-effectiveness of non-surgical treatments for women with stress urinary incontinence

OBJECTIVES

To assess the clinical effectiveness and cost-effectiveness of non-surgical treatments for women with stress urinary incontinence (SUI) through systematic review and economic modelling.

DATA SOURCES

The Cochrane Incontinence Group Specialised Register, electronic databases and the websites of relevant professional organisations and manufacturers, and the following databases: CINAHL, EMBASE, BIOSIS, Science Citation Index and Social Science Citation Index, Current Controlled Trials, ClinicalTrials.gov and the UKCRN Portfolio Database.

STUDY SELECTION

The study comprised three distinct elements. (1) A survey of 188 women with SUI to identify outcomes of importance to them (activities of daily living; sex, hygiene and lifestyle issues; emotional health; and the availability of services). (2) A systematic review and meta-analysis of non-surgical treatments for SUI to find out which are most effective by comparing results of trials (direct pairwise comparisons) and by modelling results (mixed-treatment comparisons - MTCs). A total of 88 randomised controlled trials (RCTs) and quasi-RCTs reporting data from 9721 women were identified, considering five generic interventions [pelvic floor muscle training (PFMT), electrical stimulation (ES), vaginal cones (VCs), bladder training (BT) and serotonin-noradrenaline reuptake inhibitor (SNRI) medications], in many variations and combinations. Data were available for 37 interventions and 68 treatment comparisons by direct pairwise assessment. Mixed-treatment comparison models compared 14 interventions, using data from 55 trials (6608 women). (3) Economic modelling, using a Markov model, to find out which combinations of treatments (treatment pathways) are most cost-effective for SUI.

DATA EXTRACTION

Titles and abstracts identified were assessed by one reviewer and full-text copies of all potentially relevant reports independently assessed by two reviewers. Any disagreements were resolved by consensus or arbitration by a third person.

RESULTS

Direct pairwise comparison and MTC analysis showed that the treatments were more effective than no treatment. Delivering PFMT in a more intense fashion, either through extra sessions or with biofeedback (BF), appeared to be the most effective treatment [PFMT extra sessions vs no treatment (NT) odds ratio (OR) 10.7, 95% credible interval (CrI) 5.03 to 26.2; PFMT + BF vs NT OR 12.3, 95% CrI 5.35 to 32.7]. Only when success was measured in terms of improvement was there evidence that basic PFMT was better than no treatment (PFMT basic vs NT OR 4.47, 95% CrI 2.03 to 11.9). Analysis of cost-effectiveness showed that for cure rates, the strategy using lifestyle changes and PFMT with extra sessions followed by tension-free vaginal tape (TVT) (lifestyle advice-PFMT extra sessions-TVT) had a probability of greater than 70% of being considered cost-effective for all threshold values for willingness to pay for a QALY up to 50,000 pounds. For improvement rates, lifestyle advice-PFMT extra sessions-TVT had a probability of greater than 50% of being considered cost-effective when society's willingness to pay for an additional QALY was more than 10,000 pounds. The results were most sensitive to changes in the long-term performance of PFMT and also in the relative effectiveness of basic PFMT and PFMT with extra sessions.

LIMITATIONS

Although a large number of studies were identified, few data were available for most comparisons and long-term data were sparse. Challenges for evidence synthesis were the lack of consensus on the most appropriate method for assessing incontinence and intervention protocols that were complex and varied considerably across studies.

CONCLUSIONS

More intensive forms of PFMT appear worthwhile, but further research is required to define an optimal form of more intensive therapy that is feasible and efficient for the NHS to provide, along with further definitive evidence from large, well-designed studies.

Testing cognitive function in elderly populations: the PROSPER study. PROspective Study of Pravastatin in the Elderly at Risk

OBJECTIVES

For large scale follow up studies with non-demented patients in which cognition is an endpoint, there is a need for short, inexpensive, sensitive, and reliable neuropsychological tests that are suitable for repeated measurements. The commonly used Mini-Mental-State-Examination fulfils only the first two requirements.

METHODS

In the PROspective Study of Pravastatin in the Elderly at Risk (PROSPER), 5804 elderly subjects aged 70 to 82 years were examined using a learning test (memory), a coding test (general speed), and a short version of the Stroop test (attention). Data presented here were collected at dual baseline, before randomisation for active treatment.

RESULTS

The tests proved to be reliable (with test/retest reliabilities ranging from acceptable (r=0.63) to high (r=0.88) and sensitive to detect small differences in subjects from different age categories. All tests showed significant practice effects: performance increased from the first measurement to the first follow up after two weeks.

CONCLUSION

Normative data are provided that can be used for one time neuropsychological testing as well as for assessing individual and group change. Methods for analysing cognitive change are proposed.

Climatic Change in Tasmania Inferred from a 1089-Year Tree-Ring Chronology of Huon Pine

A climatically sensitive huon pine tree-ring chronology from western Tasmania allows inferences about Austral summer temperature change since A.D. 900. Since 1965, huon pine growth has been unusually rapid for trees that are in many cases over 700 years old. This growth increase correlates well with recent anomalous warming in Tasmania on the basis of instrumental records and supports claims that a climatic change, perhaps influenced by greenhouse gases, is in progress. Although this temperature increase exceeds any that are inferred to have occurred during the past 1089 years at this location, it has not yet clearly emerged from the natural background variability of climate in this part of the Southern Hemisphere.

Analysis of urinary metabolites of tea catechins by liquid chromatography/electrospray ionization mass spectrometry

Tea has been proposed to have beneficial health effects which have been attributed to the polyphenolic compounds known as catechins. The bioavailability and biotransformation of these compounds, however, are not clearly understood. In this study, we used liquid chromatography/electrospray ionization-mass spectrometry (LC/ESI-MS) to determine urinary glucuronidated and sulfated tea catechins and their metabolites (including methylated and ring-fission metabolites) based on the detection of deprotonated molecular ions and aglycone fragment ions. The compound resolution was achieved both chromatographically and mass spectroscopically. After green tea administration, the major conjugates appeared in human, mouse, and rat urine samples were identified as monoglucuronides and monosulfates of (-)-epigallocatechin (EGC) and (-)-epicatechin. We also found O-methyl-EGC-O-glucuronides and -O-sulfates and O-methyl-epicatechin-O-sulfates in human urine. (-)-5-(3',4',5'-Trihydroxyphenyl)-gamma-valerolactone (M4) and (-)-5-(3',4'-dihydroxyphenyl)-gamma-valerolactone (M6), the ring-fission metabolites of EGC and (-)-epicatechin, respectively, were also predominantly in monoglucuronide and monosulfate forms in the urine. In comparison to rats, the urinary metabolite profiles of tea catechins in mice resemble more closely to those in humans. This is the first report describing direct simultaneous analysis of multiple tea catechin conjugates in urine samples. This method will allow more thorough investigations of the biotransformation of tea polyphenols.

Functionalized iminium salt systems for catalytic asymmetric epoxidation

A range of dihydroisoquinolinium salts containing alcohol, ether, and acetal functionalities in the nitrogen substituent has been prepared and tested as asymmetric epoxidation catalysts, providing ee's of up to ca. 60%.

Coeliac disease and autoimmune Addison's disease: a clinical pitfall

BACKGROUND

Coeliac disease has an increased prevalence in a number of autoimmune endocrine conditions. An association between coeliac disease and Addison's disease has been proposed in isolated case reports, but has not been formally studied.

AIM

To investigate the extent of this association.

DESIGN

Prospective screening of patients with confirmed Addison's disease.

METHODS

From central computerized records, we identified all living patients with a diagnosis of autoimmune Addison's disease in the past 30 years and presently attending our affiliated hospitals. After exclusions, 44 were invited to attend for screening.

RESULTS

Of 41 patients screened, five (12.2%) had coeliac disease: Three were previously diagnosed coeliacs and this was confirmed on review, including examination of biopsy material. A further two had positive IgA-endomysial antibodies. Histological confirmation was obtained in both cases. Neither had laboratory or clinical evidence of malabsorption.

DISCUSSION

In this series of patients with Addison's disease, a higher co-morbidity with coeliac disease was observed than in any previously studied endocrine condition. We recommend that coeliac serology (anti-endomysial and tissue transglutaminase antibody) testing be incorporated routinely into the autoimmune screen for other conditions in patients with Addison's disease.

Conservative treatment for urinary incontinence in Men After Prostate Surgery (MAPS): two parallel randomised controlled trials

OBJECTIVE

To determine the clinical effectiveness and cost-effectiveness of active conservative treatment, compared with standard management, in regaining urinary continence at 12 months in men with urinary incontinence at 6 weeks after a radical prostatectomy or a transurethral resection of the prostate (TURP).

BACKGROUND

Urinary incontinence after radical prostate surgery is common immediately after surgery, although the chance of incontinence is less after TURP than following radical prostatectomy.

DESIGN

Two multicentre, UK, parallel randomised controlled trials (RCTs) comparing active conservative treatment [pelvic floor muscle training (PFMT) delivered by a specialist continence physiotherapist or a specialist continence nurse] with standard management in men after radial prostatectomy and TURP.

SETTING

Men having prostate surgery were identified in 34 centres across the UK. If they had urinary incontinence, they were invited to enroll in the RCT.

PARTICIPANTS

Men with urinary incontinence at 6 weeks after prostate surgery were eligible to be randomised if they consented and were able to comply with the intervention.

INTERVENTIONS

Eligible men were randomised to attend four sessions with a therapist over a 3-month period. The therapists provided standardised PFMT and bladder training for male urinary incontinence and erectile dysfunction. The control group continued with standard management.

MAIN OUTCOME MEASURES

The primary outcome of clinical effectiveness was urinary incontinence at 12 months after randomisation, and the primary measure of cost-effectiveness was incremental cost per quality-adjusted life-year (QALY). Outcome data were collected by postal questionnaires at 3, 6, 9 and 12 months.

RESULTS

Within the radical group (n = 411), 92% of the men in the intervention group attended at least one therapy visit and were more likely than those in the control group to be carrying out any PFMT at 12 months {adjusted risk ratio (RR) 1.30 [95% confidence interval (CI) 1.09 to 1.53]}. The absolute risk difference in urinary incontinence rates at 12 months between the intervention (75.5%) and control (77.4%) groups was -1.9% (95% CI -10% to 6%). NHS costs were higher in the intervention group [£ 181.02 (95% CI £ 107 to £ 255)] but there was no evidence of a difference in societal costs, and QALYs were virtually identical for both groups. Within the TURP group (n = 442), over 85% of men in the intervention group attended at least one therapy visit and were more likely to be carrying out any PFMT at 12 months after randomisation [adjusted RR 3.20 (95% CI 2.37 to 4.32)]. The absolute risk difference in urinary incontinence rates at 12 months between the intervention (64.9%) and control (61.5%) groups for the unadjusted intention-to-treat analysis was 3.4% (95% CI -6% to 13%). NHS costs [£ 209 (95% CI £ 147 to £ 271)] and societal costs [£ 420 (95% CI £ 54 to £ 785)] were statistically significantly higher in the intervention group but QALYs were virtually identical.

CONCLUSIONS

The provision of one-to-one conservative physical therapy for men with urinary incontinence after prostate surgery is unlikely to be effective or cost-effective compared with standard care that includes the provision of information about conducting PFMT. Future work should include research into the value of different surgical options in controlling urinary incontinence.

Local administration of EAA antagonists blocks light-induced phase shifts and c-fos expression in hamster SCN

Syrian hamsters were fitted with guide cannulas stereotaxically aimed at the suprachiasmatic nuclei (SCN) and housed in constant darkness in cages equipped with running wheels. Animals received 300-nl injections of either vehicle, CNQX, or MK-801 into the region of the SCN 5 min before a brief (10 min at 20 lx) light exposure. Local administration of either 1 mM CNQX or 1 mM MK-801 at circadian time (CT) 18 significantly inhibited light-induced phase advances (vehicle = 52 +/- 9 min; CNQX = 12 +/- 7 min; MK-801 = 12 +/- 5 min; P < 0.05 relative to vehicle+light group). The effects of both drugs were reversible and dose related. Injection of 1 mM MK-801 at CT13.5 resulted in a 71% inhibition of light-induced phase delays (vehicle = -51 +/- 6 min; MK-801 = -15 +/- 5 min; P < 0.05), while CNQX failed to significantly inhibit light-induced phase delays (-39 +/- 10 min). Local administration of either 1 mM CNQX or MK-801 into the SCN region reduced the number of Fos-immunoreactive cells relative to vehicle-injected controls by approximately 32 and 44%, respectively (vehicle = 951 +/- 79; CNQX = 643 +/- 135, P < 0.05; MK-801 = 533 +/- 143, P < 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)

Two-dimensional gel analyses of the 24-kDa cap binding protein from poliovirus-infected and uninfected HeLa cells

The 24-kDa cap binding protein (CBP) from uninfected, mock-infected and poliovirus-infected HeLa cell extracts was isolated by m7GTP affinity chromatography and examined by isoelectric focusing followed by SDS-PAGE. Two major species (pI 6.7 and 7.1) and two minor species (pI 6.5 and 6.8) were found in all cases. Preparations from postribosomal supernate (S200) and the supernate from 0.5 M KCl washed ribosomes (RSW) also demonstrated these same four species. We conclude that there are no detectable differences between ribosome-associated and soluble 24-kDa CBP and that the 24-kDa CBP is not detectably altered by poliovirus infection. We also report the presence of a previously undescribed 16-kDa polypeptide(s) doublet that copurifies with the 24-kDa CBP from uninfected, mock-infected and poliovirus-infected HeLa cells.

Volatile organic compounds emitted by filamentous fungi isolated from flooded homes after Hurricane Sandy show toxicity in a Drosophila bioassay

Superstorm Sandy provided an opportunity to study filamentous fungi (molds) associated with winter storm damage. We collected 36 morphologically distinct fungal isolates from flooded buildings. By combining traditional morphological and cultural characters with an analysis of ITS sequences (the fungal DNA barcode), we identified 24 fungal species that belong to eight genera: Penicillium (11 species), Fusarium (four species), Aspergillus (three species), Trichoderma (two species), and one species each of Metarhizium, Mucor, Pestalotiopsis, and Umbelopsis. Then, we used a Drosophila larval assay to assess possible toxicity of volatile organic compounds (VOCs) emitted by these molds. When cultured in a shared atmosphere with growing cultures of molds isolated after Hurricane Sandy, larval toxicity ranged from 15 to 80%. VOCs from Aspergillus niger 129B were the most toxic yielding 80% mortality to Drosophila after 12 days. The VOCs from Trichoderma longibrachiatum 117, Mucor racemosus 138a, and Metarhizium anisopliae 124 were relatively non-toxigenic. A preliminary analysis of VOCs was conducted using solid-phase microextraction-gas chromatography-mass spectrometry from two of the most toxic, two of the least toxic, and two species of intermediate toxicity. The more toxic molds produced higher concentrations of 1-octen-3-ol, 3-octanone, 3-octanol, 2-octen-1-ol, and 2-nonanone; while the less toxic molds produced more 3-methyl-1-butanol and 2-methyl-1-propanol, or an overall lower amount of volatiles. Our data support the hypothesis that at certain concentrations, some VOCs emitted by indoor molds are toxigenic.

Quality of life improvements following one year of setmelanotide in children and adult patients with Bardet-Biedl syndrome: phase 3 trial results

BACKGROUND

Bardet-Biedl syndrome is a rare genetic disease associated with hyperphagia and early-onset, severe obesity. There is limited evidence on how hyperphagia and obesity affect health-related quality of life in patients with Bardet-Biedl syndrome, and on how management of these symptoms may influence disease burden. This analysis evaluated changes in health-related quality of life in adults and children with Bardet-Biedl syndrome in a Phase 3 trial following 1 year of setmelanotide treatment (ClinicalTrials.gov identifier: NCT03746522).

METHODS

Patients with Bardet-Biedl syndrome and obesity received 52 weeks of treatment with setmelanotide and completed various self-reported health-related quality of life measures. Patients aged < 18 years or their caregiver completed the Pediatric Quality of Life Inventory (PedsQL; meaningful improvement, 4.4-point change); adults aged ≥ 18 years completed the Impact of Weight on Quality of Life Questionnaire-Lite (IWQOL-Lite; meaningful improvement range, 7.7-12-point change). Descriptive outcomes were reported in patients with data both at active treatment baseline and after 52 weeks of treatment.

RESULTS

Twenty patients (< 18 years, n = 9; ≥ 18 years, n = 11) reported health-related quality of life at baseline and 52 weeks. For children and adolescents, PedsQL score mean change from baseline after 52 weeks was + 11.2; all patients with PedsQL impairment at baseline (n = 4) experienced clinically meaningful improvement. In adults, IWQOL-Lite score mean change from baseline was + 12.0. Of adults with IWQOL-Lite impairment at baseline (n = 8), 62.5% experienced clinically meaningful improvement. In adults, IWQOL-Lite score was significantly correlated with changes in percent body weight (P = 0.0037) and body mass index (P = 0.0098).

CONCLUSIONS

After 1 year of setmelanotide, patients reported clinically meaningful improvements across multiple health-related quality of life measures. This study highlights the need to address the impaired health-related quality of life in Bardet-Biedl syndrome, and supports utility of setmelanotide for reducing this burden. Trial Registration NCT03746522. Registered November 19, 2018, https://clinicaltrials.gov/ct2/show/NCT03746522 .

Maternal, placental, and fetal distribution of titanium after repeated titanium dioxide nanoparticle inhalation through pregnancy

Epidemiological studies have associated ambient engineered nanomaterials or ultrafine particulate matter (PM_0.1), collectively referred to as nanoparticles (NPs), with adverse pregnancy outcomes including miscarriage, preterm labor, and fetal growth restriction. Evidence from non-pregnant models demonstrate that NPs can cross the lung air-blood barrier and circulate systemically. Therefore, inhalation of NPs during pregnancy leading to fetoplacental exposure has garnered attention. The purpose of this study was to evaluate the distribution of inhaled titanium dioxide nanoparticles (nano-TiO₂) from the maternal lung to maternal and fetal systemic tissues. Pregnant Sprague Dawley rats were administered whole-body exposure to filtered air or of nano-TiO₂ aerosols (9.96 ± 0.06 mg/m³) between gestational day (GD) 4 and 19. On GD 20 maternal, placental, and fetal tissues were harvested then digested for ICP-MS analysis to measure concentrations of titanium (Ti). TEM was used to visualize particle internalization by the placental syncytium. The results demonstrate the extrapulmonary distribution of Ti to various maternal organs during pregnancy. Our study found Ti accumulation in the decidua/junctional and labyrinth zones of placentas embedded in all sections of uterine horns. Further, NPs deposited in the placenta, identified by TEM, were found intracellularly within nuclear, endoplasmic reticulum, and vesicle organelles. This study identified the systemic distribution and placental accumulation of Ti after nano-TiO₂ aerosol inhalation in a pregnancy model. These findings arouse concerns for poor air quality for pregnant women and possible contributions to adverse pregnancy outcomes.

Removing leakage-induced correlated errors in superconducting quantum error correction

Quantum computing can become scalable through error correction, but logical error rates only decrease with system size when physical errors are sufficiently uncorrelated. During computation, unused high energy levels of the qubits can become excited, creating leakage states that are long-lived and mobile. Particularly for superconducting transmon qubits, this leakage opens a path to errors that are correlated in space and time. Here, we report a reset protocol that returns a qubit to the ground state from all relevant higher level states. We test its performance with the bit-flip stabilizer code, a simplified version of the surface code for quantum error correction. We investigate the accumulation and dynamics of leakage during error correction. Using this protocol, we find lower rates of logical errors and an improved scaling and stability of error suppression with increasing qubit number. This demonstration provides a key step on the path towards scalable quantum computing.

Effect of mean airway pressure on gas exchange during high-frequency oscillatory ventilation

We studied the effect of mean airway pressure (Paw) on gas exchange during high-frequency oscillatory ventilation in 14 adult rabbits before and after pulmonary saline lavage. Sinusoidal volume changes were delivered through a tracheostomy at 16 Hz, a tidal volume of 1 or 2 ml/kg, and inspired O2 fraction of 0.5. Arterial PO2 and PCO2 (PaO2, PaCO2), lung volume change, and venous admixture were measured at Paw from 5 to 25 cmH2O after either deflation from total lung capacity or inflation from relaxation volume (Vr). The rabbits were lavaged with saline until PaO2 was less than 70 Torr, and all measurements were repeated. Lung volume change was measured in a pressure plethysmograph. Raising Paw from 5 to 25 cmH2O increased lung volume by 48-50 ml above Vr in both healthy and lavaged rabbits. Before lavage, PaO2 was relatively insensitive to changes in Paw, but after lavage PaO2 increased with Paw from 42.8 +/- 7.8 to 137.3 +/- 18.3 (SE) Torr (P less than 0.001). PaCO2 was insensitive to Paw change before and after lavage. At each Paw after lavage, lung volume was larger, venous admixture smaller, and PaO2 higher after deflation from total lung capacity than after inflation from Vr. This study shows that the effect of increased Paw on PaO2 is mediated through an increase in lung volume. In saline-lavaged lungs, equal distending pressures do not necessarily imply equal lung volumes and thus do not imply equal PaO2.

Q fever epidemic in Victorian general practice

In 1979, 110 people associated with a local rural abattoir presented with an acute febrile illness thought to be Q fever. Of these, 70 were shown by serotesting to have had Q fever, and one was shown to have had leptospirosis alone. Four individuals had mixed infections of Q fever with another zoonotic infection, two with leptospirosis, and two with brucellosis. Only 44% of suspected cases of Q fever were shown to have complement-fixing antibodies to Q fever four weeks after the infection, but 74% had anti-bodies 12 weeks after infection. This epidemic of Q fever occurred soon after the abattoir began to slaughter feral goats for the first time; there is reason to believe that the epidemic may have been related to the introduction of this practice.

Nucleotide sequence and in vitro expression of the capsid protein gene of tobacco ringspot virus

The nucleotide sequence of the 3' terminal 2022 nucleotides (nt) of tobacco ringspot virus (TobRV) RNA 2 has been determined. Protein microsequence analysis of the amino-terminal residues of purified capsid protein localized the capsid protein gene between nt 2014 and 583 (from the 3' terminus) of this sequence. The proteolytic cleavage site that is processed to liberate the capsid protein from the RNA 2-encoded polyprotein was identified as Cys-Ala. The predicted translation product from the gene is a 477 amino acid long polypeptide with a calculated MW of 53 kDa. The gene was modified at the 5' end to facilitate sub-cloning, and to provide it with a methionine initiation codon. The modified gene was sub-cloned, transcribed in vitro and expressed in a rabbit reticulocyte lysate translation system, where it directed the synthesis of a 53 kDa polypeptide. Garnier-Osguthorpe-Robson analyses of the secondary structure of the capsid protein predicted the presence of three beta sheet domains, which suggests that this nepovirus capsid may be structurally analogous to those of the como- and picornaviruses. These and other results from computer analyses of the nucleic acid and amino acid sequences, and comparisons with the capsid proteins of nepoviruses and other related viruses are discussed.

Expression of tobacco ringspot virus capsid protein and satellite RNA in insect cells and three-dimensional structure of tobacco ringspot virus-like particles

The capsid protein gene of tobacco ringspot virus (TobRV), which had been modified to contain an amino-terminal methionine codon, was ligated into a baculovirus transfer vector downstream from the polyhedrin promoter. The resulting plasmid was cotransfected with linearized baculovirus DNA into insect cells. Recombinant baculovirus expressed high levels of the TobRV capsid protein that assembled to form virus-like particles that were similar in size and shape to authentic TobRV capsids. These virus-like particles did not encapsidate any RNA, including the capsid protein mRNA. The capsid protein mRNA is a truncated RNA 2, which may lack a putative encapsidation signal. To determine whether an intact packaging substrate could be encapsidated by the TobRV capsid protein, another recombinant baculovirus, concomitantly expressing both capsid protein and TobRV satellite RNA, was constructed. Surprisingly, the vast majority of the satellite RNA molecules expressed from this recombinant baculovirus were ligated in the insect cells to form circular RNA molecules. Like circular forms of satellite RNA generated in planta, these circular satellite molecules remained unencapsidated by the TobRV capsid protein. Computer-generated three-dimensional reconstruction using electron cryomicrographs of the empty virus-like particles allowed the first structural analyses of any nepovirus capsid. This 22-A resolution reconstruction resembled capsids of other members of the picornavirus superfamily. These data support the hypothesis that the nepovirus capsid is structurally analogous to those of the como- and picornaviruses.

Elimination of germ-line tandemly repeated sequences from the somatic genome of the ciliate Oxytricha fallax

The ciliated protozoa exhibit nuclear dimorphism. The genome of the somatic macronucleus arises from the germ-line genome of the micronucleus following conjugation. We have studied the fates of highly repetitious sequences in this process. Two cloned, tandemly repeated sequences from the micronucleus of Oxytricha fallax were used as probes in hybridizations to micronuclear and macronuclear DNA. The results of these experiments show: (1) the cloned repeats are members of two apparently unrelated repetitious sequence families, which each appear to comprise a few percent of the micronuclear genome, and (2) the amount of either family in the macronuclei from which our DNA was prepared is about 1/15 that found in an equal number of diploid micronuclei. Most, if not all, of the apparent macronuclear copies of these repeats can be accounted for by micronuclear contamination, which strongly suggests that these sequences are eliminated from the macronuclei and have no vegetative function.

Circulating zearalenone and its metabolites differ in women due to body mass index and food intake

The environmental estrogen, zearalenone (ZEA), is found in the food supply from Fusarium fungal contamination in grains and sometimes used as a growth promoter for beef cattle. Long-term exposure to ZEA and its metabolites may present health risk due to higher estrogenic activity. Serum ZEA metabolites were measured to determine the exposure and the association with food intake in 48 overweight/obese women (52 ± 9 years). The free and conjugated ZEA indicated the highest detection rate of all the metabolites. Conjugated ZEA and total ZEA metabolites were lower (p = 0.02) in overweight/obese than normal weight women, and free metabolites were either the same or showed a trend to be higher. In addition, those with highest (280-480 g/d) compared those with lowest (<115 g/d) meat consumption had higher conjugated serum ZEA metabolite concentrations (p < 0.05). Intakes of other food groups (i.e., dairy, cereal, etc.) were not associated with ZEA metabolites. These findings indicate that ZEA and its metabolites are detectable in nearly all women and concentrations are associated with greater meat intake, and influenced by body mass index. Determining how the food supply influences human concentrations of ZEA metabolites is warranted, as well as determining vulnerable populations.