Outburst of Jupiter's synchrotron radiation after the impact of comet Shoemaker-Levy 9.

Jupiter's nonthermal microwave emission, as measured by a global network of 11 radio telescopes, increased dramatically during the Shoemaker-Levy 9 impacts. The increase was wavelength-dependent, varying from approximately 10 percent at 70 to 90 centimeters to approximately 45 percent at 6 and 36 centimeters. The radio spectrum hardened (flattened toward shorter wavelengths) considerably during the week of impacts and continued to harden afterward. After the week of cometary impacts, the flux density began to subside at all wavelengths and was still declining 3 months later. Very Large Array and Australia Telescope images of the brightness distribution showed the enhancement to be localized in longitude and concentrated near the magnetic equator. The evidence therefore suggests that the increase in flux density was caused by a change in the resident particle population, for example, through an energization or spatial redistribution of the emitting particles.

Comparison of chronic physical and emotional social defeat stress effects on mesocorticolimbic circuit activation and voluntary consumption of morphine.

Chronic social defeat stress (CSDS) is a well-established rodent model of depression that induces persistent social avoidance. CSDS triggers molecular adaptations throughout the mesocorticolimbic reward circuit, including changes in the activity of dopamine neurons in the ventral tegmental area (VTA), that may also influence drug reward. One limitation of traditional, physical CSDS (PS) is that injury complicates the study of opiate drugs like morphine. Thus, we sought to characterize a variation of CSDS, termed emotional CSDS (ES), that eliminates this confound. We assessed the effect of PS and ES on mesocorticolimbic circuit activation, VTA gene expression, and morphine intake. We found that PS and ES similarly induced ΔFosB in the hippocampus, but only PS significantly increased ΔFosB expression in the prefrontal cortex and striatum. In contrast, cFos expression was similarly reduced by both PS and ES. Interestingly, we found that PS and ES similarly increased voluntary morphine consumption immediately following stress, despite differences in the magnitude of the depressive phenotype and striatal ΔFosB expression at this time point. Combined, these data suggest that both stress paradigms may be useful for investigation of stress-induced changes in drug behavior.

Prevention of acute dystonic reactions in patients beginning high-potency neuroleptics.

The authors performed a prospective double-blind study of 39 inpatients beginning high-potency neuroleptics. Patients were randomly assigned to a 7-day course of benztropine or placebo in addition to a neuroleptic. Of 17 patients receiving placebo, eight (47%) suffered an acute dystonic reaction; of 22 patients receiving benztropine, none suffered this reaction--a highly significant difference. The authors also found minimal anticholinergic toxicity attributable to the addition of benztropine to the neuroleptic regimen. These results suggest that an initial 7-day prophylaxis with benztropine is a high-benefit, low-risk adjunctive treatment to neuroleptic therapy.

A comparison of nonculture-dependent methods for detection of Chlamydia trachomatis infections in pregnant women.

Two nonculture-dependent methods for the detection of Chlamydia trachomatis in endocervical samples from obstetric patients were compared with routine isolation in McCoy cell cultures. When compared with culture, the sensitivities and specificities of the methods were: direct fluorescent antibody staining (MicroTrak [Syva Co.]) 98.1 and 95.4%, and enzyme immunoassay (Chlamydiazyme [Abbott Laboratories]) 96.3 and 92.9%, respectively. In 89% of apparent false-positive direct fluorescent antibody cases and 64% of enzyme immunoassay cases, an additional positive nonculture result was considered to indicate infection missed by culture. Considering these data, revised sensitivities were 84.4% for culture, 95.2% for direct fluorescent antibody, and 95.3% for enzyme immunoassay. Revised specificities were 99.5% for direct fluorescent antibody and 97.3% for enzyme immunoassay. Both nonculture tests appear acceptable for screening high-risk obstetric patients, and may be more sensitive than routine cell culture.

EtOH self-administration in anticipation of noise stress in C57BL/6J mice.

C57BL/6J mice were studied for self-administration of ethanol (EtOH) during a signal period that preceded delivery of an environmental stressor (noise) in the home cage. Animals were given 5 weeks of conditioning in which a 5-min period of 75-dB pulsed noise (SIGNAL) preceded a 20-min period of more intense, 90-dB pulsed noise (NOISE) five times daily. EtOH (10% w/v) was then provided in a choice procedure, and drink tube contacts were monitored by computer. Mice that had received the 5 weeks of SIGNAL and NOISE pairings showed an increase in EtOH-seeking behavior, as reflected in EtOH tube contacts during the SIGNAL period. The increase was significant as compared to contacts during baseline or QUIET periods and also as compared to contacts during the same period for control (Ctrl) mice that had received only the 75-dB SIGNAL during conditioning. A subsequent test for passive avoidance confirmed that the 75-dB SIGNAL was aversive for mice that had received noise conditioning but not for Ctrl mice. In sum, the results were in accord with a priori predictions that mice would not show increased EtOH tube contacts during occurrence of intense noise itself but would show increased contacts during the signal that preceded noise. These results were interpreted as preliminary evidence that C57BL/6J mice show self-administration of EtOH in anticipation of an environmental stressor.

Tissue response to biodegradable injectable microcapsules.

Biodegradable microcapsules have been shown to be capable of delivering a sustained release of various medicinal agents. We have observed an initial minimal, sharply localized, acute inflammatory response to intramuscularly injected microcapsules produced from various polymers. Evaluation of later time points has shown a diminishing macrophage, foreign body giant cell, and connective tissue response along with actual microcapsule degradation. No fibrous capsule formation was seen. Complete resolution of the tissue reaction can be expected, with the time frame depending upon the polymer utilized. Published experimental results report similar minor tissue responses to a variety of injected biodegradable microcapsules.

The EMS response to the Oklahoma City bombing.

This is a descriptive study of the Emergency Medical Services response to a bombing of a United States Federal Building in Oklahoma City, Oklahoma on 19 April 1995. The explosion emanated from a rented truck parked in the front of the building. The force of the explosion destroyed three of the four support columns in the front of the building and resulted in a pancaking effect of the upper floors onto the lower floors. There were three distinct phases of the medical response: 1) Immediately available local EMS ambulances and staff; 2) Additional ambulances staffed by recalled, off-duty personnel; and 3) mutual-aid ambulances and personnel from the surrounding communities. There were 361 persons in the building at the time of the explosion, 163 of these perished. Within the first hour of the explosion, 139 patients were transported to area hospitals. Of these, 32% were in critical condition. During the day of the explosion, 444 persons were treated for physical injuries: 410 of these were related to the explosion and 14, including one with fatal injuries, were sustained during search and rescue attempts. A total of 354 (80%) were treated and released from emergency departments, and 90 (20%) were admitted to hospitals. Six of the transported victims either were dead on arrival to the emergency department or died after admission to the hospital. Of those who died, 95% of the deaths were related to blunt trauma associated with the collapse of the structure. Only three persons were extricated alive after the first five hours following the explosion. The scene became flooded with volunteers who, although their intentions were to provide help and aid to those injured, created a substantial logistical problem for Incident Command. Several other lessons were learned: 1) Telephone lines and cells became overloaded, but the Hospital Emergency Administrative Radio system was operational only in three of the 15 hospitals; 2) Volunteer personnel should have responded to the hospitals and not to the scene; and 3) Training was an essential for the success of such a response. Thus, the success of this operation was a function of the intense training, practice, and coordination between multiple agencies.

Multivariate permutation analysis associates multiple polymorphisms with subphenotypes of major depression.

Unipolar major depressive disorder (MDD) is a prevalent, disabling condition with multiple genetic and environmental factors impacting disease risk. The diagnosis of MDD relies on a cumulative measure derived from multiple trait dimensions and alone is limited in elucidating MDD genetic determinants. We and others have proposed that MDD may be better dissected using paradigms that assess how specific genes associate with component features of MDD. This within-disease design requires both a well-phenotyped cohort and a robust statistical approach that retains power with multiple tests of genetic association. In the present study, common polymorphic variants of genes related to central monoaminergic and cholinergic pathways that previous studies align with functional change in vitro or depression associations in vivo were genotyped in 110 individuals with unipolar MDD. Subphenotypic characteristics were examined using responses to individual items assessed with the Structured Clinical Interview for Diagnostic and Statistical Manual of Mental Disorders (DSM IV), the 17-item Hamilton Rating Scale for Depression (HAM-D) and the NEO Five Factor Inventory. Multivariate Permutation Testing (MPT) was used to infer genotype-phenotype relationships underlying dimensional findings within clinical categories. MPT analyses show significant associations of the norepinephrine transporter (NET, SLC6A2) -182 T/C (rs2242446) with recurrent depression [odds ratio, OR = 4.15 (1.91-9.02)], NET -3081 A/T (rs28386840) with increase in appetite [OR = 3.58 (1.53-8.39)] and the presynaptic choline transporter (CHT, SLC5A7) Ile89Val (rs1013940) with HAM-D-17 total score {i.e. overall depression severity [OR = 2.74 (1.05-7.18)]}. These relationships illustrate an approach to the elucidation of gene influences on trait components of MDD and with replication, may help identify MDD subpopulations that can benefit from more targeted pharmacotherapy.

Effect of selenium intake and fetal age on mRNA levels of two selenoproteins in porcine fetal and maternal liver.

The objective of this study was to determine if levels of mRNA encoding cytosolic glutathione peroxidase (cGPx) and thioredoxin reductase (TrxR-1) change during fetal development, and if maternal Se intake during gestation affects the mRNA levels of these proteins. Prepubertal gilts (n = 24) were randomly assigned to either Se-adequate (0.39 ppm of Se; n = 12) or Se-deficient (0.05 ppm of Se; n = 12) diets, 6 wk before breeding. Maternal liver was collected at d 10, 45, 70, and 114 of pregnancy, and fetal liver samples were collected at the same times except d 10. Complementary DNA sequences encoding cGPx and TrxR-1 were cloned and sequenced. Quantitative real-time PCR analysis indicated that levels of mRNA for cGPx in fetal liver decreased more than 3-fold between d 45 and 114 of gestation. Although the gilts were only marginally deficient in Se, and maternal Se intake did not affect cGPx mRNA levels in fetal liver, the low-Se diet tended (P = 0.1) to reduce fetal TrxR-1 mRNA levels. In the liver of the dams, the low Se intake did not affect mRNA levels for either cGPx or TrxR-1. Compared with the liver of the dams, mRNA levels for cGPx were about 3.5 times lower in fetal liver. Results of this study support the hypothesis that neonatal pigs are born with reduced cGPx corresponding to reduced cGPx mRNA levels during late gestation.

Multidisciplinary discharge assessment of the medically and socially high-risk infant.

Discharge from a neonatal intensive care unit (NICU) requires assessment, coordination, and possible intervention by a multidisciplinary team. The infant's health condition and the family's social situation must be considered before discharge to design a discharge plan for the child's long-term well-being. This article presents the neonatal discharge assessment tool (N-DAT) as a method to identify risks at the time of discharge. The tool offers specific recommendations for use with infants who are medically or socially high risk. The implications for the NICU team and for coordination with community providers are discussed.

Complex organization of the mitochondrial genome of petaloid CMS carrot.

The petaloid trait in carrot is a mitochondrially associated homeotic-like conversion of stamens into petals which results in cytoplasmic male sterility (cms), but little is understood about the phenomenon at the molecular level. Identification of region(s) of the mitochndrial (mt) genome that are causally implicated in cms may be aided by a physical map of cms-associated mtDNA. The mt genome of petaloid cms carrot is 255 kb in length and contains three pairs of repeated sequences, two in direct orientation and one in inverted orientation. All regions of the genome are present in equal stoichiometries, but the arrangement of the repeated sequences prevented the representation of the entire genome as a single master circle or multiple subgenomes. An alternative model of mtDNA replication that accounts for our data is discussed.

Plasmid RNA polymerase-like mitochondrial sequences in Agaricus bitorquis.

A linear mitochondrial plasmid, pEM, found in certain isolates of the basidiomycete Agaricus bitorquis, potentially encodes virus-like DNA and RNA polymerases. Mitochondrial DNA from Agaricus bisporus that hybridizes to an internal region of pEM contains a fragmented and potentially non-functional version of the carboxy terminal end of the plasmid RNA polymerase. In this study, we present the sequence of the corresponding region of mitochondrial DNA from A. bitorquis. This sequence contained the same region of the plasmid RNA polymerase gene as was reported for the mitochondrial DNA of A. bisporus, and the level of similarity between the A. bisporus and A. bitorquis mitochondrial sequences was much higher than the level of similarity between either mitochondrial sequence and the plasmid. We propose that this plasmid RNA polymerase-like sequence was present in the Agaricus mitochondrial genome before the divergence of A. bisporus and A. bitorquis, and thus is unlikely to be a recent derivative of the plasmid pEM.

Widespread distribution of low-copy-number variants of mitochondrial plasmid pEM in the genus Agaricus.

The incidence of the linear mitochondrial plasmid pEM in Agaricus spp. was believed to be rare, based on visualization by gel electrophoresis and Southern hybridization. However, we report in this study PCR amplification of pEM-like sequences from all but one species of Agaricus examined. Regions amplified included (1) the pEM RNA polymerase gene and (2) adjoining carboxy-termini of the DNA and RNA polymerase genes. Sequence data from the RNA polymerase-like products support a plasmid, rather than mitochondrial, origin for these sequences. Sequence variation was low, and most differences were silent or conservative at the amino acid level. Stop codons were found in two of seven sequence types suggesting that functional constraints are low. A parsimony-derived phylogeny for these sequences did not match expected phylogenies for the host species. Recent acquisition of the plasmid is presented as the most likely hypothesis explaining these observations.

Homology between mitochondrial DNA of Agaricus bisporus and an internal portion of a linear mitochondrial plasmid of Agaricus bitorquis.

Agaricus bisporus, the cultivated mushroom, contains a mitochondrial fragment (50H) which was previously demonstrated by Southern hybridization to have sequence similarity to an internal region of pEM, a linear mitochondrial plasmid of Agaricus bitorquis. The nucleotide sequence of 50H was determined and compared to the sequence of the corresponding pEM fragment. The region of sequence homology on pEM is contained within an open reading frame (ORF) that may encode an RNA polymerase, but 50H is neither an intact nor a complete copy of the ORF. pEM also contains an ORF with characteristics of genes for virus-encoded DNA polymerases. pEM appears to be very similar to other linear mitochondrial plasmids (in fungi and higher plants) reported to contain ORFs that may encode the same types of polymerases. The potential functionality of the pEM sequence suggests that it has diverged less than the mitochondrial fragment from a common ancestor.

Comparison of two commercially available isolation systems for Chlamydia trachomatis.

In a comparison of two commercially available chlamydial isolation systems in which cycloheximide-treated McCoy cell monolayers are used, the system from Bartels Immunodiagnostic Supplies, Inc., Bellevue, Wash., was found to be superior to that from M. A. Bioproducts, Walkersville, Md. for the detection of Chlamydia trachomatis by iodine staining. Of 288 clinical specimens run in parallel, 47 (16.3%) were positive, with 16 of 47 positive results detected in the Bartels system only and 1 of 47 positive results detected in the M. A. Bioproducts system only (P less than 0.001). A comparison of the number of inclusion-forming units per cover slip from clinical specimens and passaged isolates also showed that the Bartels cell system demonstrated higher inclusion counts than the M. A. Bioproducts system. In routine clinical use, overall isolation rates were higher (P less than 0.001) and contamination rates were lower (P less than 0.001) with the Bartels system as compared with results obtained in a previous time period in which the M. A. Bioproducts system was used.

Rapid detection of Pneumocystis carinii in bronchoalveolar lavage samples by using Cellufluor staining.

Cellufluor (Calcofluor white) has been found to be a useful, rapid chemofluorescent stain for detection of Pneumocystis carinii cysts in bronchoalveolar lavage samples. When compared with toluidine blue O and Giemsa stains on 45 specimens (22 positive and 23 negative), the sensitivity and specificity of the Cellufluor stain were 95 and 100%, respectively.

Reduced symptoms of Verticillium wilt in transgenic tomato expressing a bacterial ACC deaminase.

Summary Ethylene evolved during compatible or susceptible disease interactions may hasten and/or worsen disease symptom development; if so, the prevention of disease-response ethylene should reduce disease symptoms. We have examined the effects of reduced ethylene synthesis on Verticillium wilt (causal organism, Verticillium dahliae) of tomato by transforming tomato with ACC deaminase, which cleaves ACC, the immediate biosynthetic precursor of ethylene in plants. Three promoters were used to express ACC deaminase in the plant: (i) CaMV 35S (constitutive expression); (ii) rolD (limits expression specifically to the site of Verticillium infection, i.e. the roots); and (iii) prb-1b (limits expression to certain environmental cues, e.g. disease infection). Significant reductions in the symptoms of Verticillium wilt were obtained for rolD- and prb-1b-, but not for 35S-transformants. The pathogen was detected in stem sections of plants with reduced symptoms, suggesting that reduced ethylene synthesis results in increased disease tolerance. The effective control of formerly recalcitrant diseases such as Verticillium wilt may thus be obtained by preventing disease-related ethylene production via the tissue-specific expression of ACC deaminase.