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The United States (US) Environmental Protection Agency (EPA) included strontium (Sr) in the Contaminant Candidate List 3 as a potential chemical for future regulation. Sr occurrence data at US public water systems were gathered under the Unregulated Contaminant Monitoring Rule 3, and the EPA assessed the potential to improve public health as well as the costs of promulgating a Sr regulation. The EPA delayed issuing a final regulatory determination for Sr to gather more information, including treatment research on removing Sr from drinking water for which there is very limited data, but the health reference level was lowered to 1.5 mg L−1. The objective of this research was to evaluate the effectiveness of full-scale ion exchange (IX) and lime softening on Sr removal from groundwater at eight drinking water treatment plants in Ohio. IX softeners removed 92–98% of Sr which utilities blended to achieve Sr concentrations ranging from 2.7–7.0 mg L−1resulting in an overall removal including blending of 67–81%. Lime softening plants achieved 44–95% Sr removal on average, resulting in finished water Sr concentrations ranging from 0.2–4.9 mg L−1. Sr removal appeared to parallel calcium removal, and the Sr concentration in the finished water might be limited by the Sr concentration in the raw water. Under normal operating conditions, only 2 of the 8 softening plants consistently achieved finished water Sr concentrations less than the health reference level. Although treatment modifications likely could improve Sr removal at increased operating costs, the finished water concentration might be limited by blending at IX plants and the raw water Sr concentration at lime softening plants.

The water industry is experiencing renewed interest in optimizing manganese (Mn) control. With greater knowledge of Mn in drinking water, water utilities will be better prepared to develop effective management strategies.

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Although use of buprenorphine in the treatment of opioid dependence is expected to continue to increase, little is known about the optimal setting for providing the medical and psychosocial care required with buprenorphine pharmacotherapy.

Our previous observations indicated that upon infection with minute virus of mice (MVM), Ehrlich ascites cells lose a transcription elongation activity which is essential for the readthrough of the MVM attenuator. This was monitored by the ability of extracts from uninfected but not from infected cells to support readthrough of the P4 attenuator when added to partially purified transcription elongation complexes. We have investigated the nature of this change in transcription elongation following MVM infection. In this communication, we show that infection of Ehrlich ascites cells with MVM leads to a general shift in the length of nascent mRNA synthesized in isolated nuclei and separated by sucrose gradients. Furthermore, infection leads to attenuation of transcription of the cellular gene c-fos but not c-myc. We show biochemical evidence to support a model by which, following MVM infection, there is a functional reduction in the activity of a TFIIS-like general transcriptional elongation activity.

Minute virus of mice (MVM) nucleoprotein complexes were leached from infected cell nuclei in the presence of a hypotonic buffer. Detailed biochemical analyses performed on the extracted complexes revealed nucleoprotein complexes sedimenting together with virions at 110S and defective particles sedimenting at 50S. In contrast to the virions, the nucleoprotein complexes were found to be sensitive to treatment with DNase, Sarkosyl, and heparin. They were found to be composed of replicative forms of MVM DNA and cellular histones. After extensive micrococcal nuclease digestion performed on purified nucleoprotein complexes, a viral nucleosomes core containing a DNA segment of about 140 base pairs in length was identified. These complexes when visualized by electron microscopy revealed the existence of beaded structures (minichromosomes) having 26 and 52 beads per monomer and dimer molecules, respectively. We suggest that the organization of the intracellular viral DNA in a minichromosome structure is an essential step in the virus growth cycle.

Political debate about how the changing age distribution of the population would affect higher education enrollments led presidents of Michigan's constitutionally autonomous state universities to sponsor “systemwide” enrollment projections based on calculations of the participation rates and credit hour loads of 66 student subgroups that were defined by age, gender, and degree level. The 1985 figures were applied to cohort population projections in order to assess the impact of an aging population on the enrollments of 1990, 1995, and 2000. “Recession” and “recovery” regression models were then developed and used to explore the 1974–1985 relationship between enrollments and economic variables and to generate alternate projections.

To characterize the transcriptional organization and regulation of minute virus of mice, an autonomous parvovirus, viral transcriptional complexes were isolated and cleaved with restriction enzymes. The in vivo preinitiated nascent RNA was elongated in vitro in the presence of [alpha-32P]UTP to generate runoff transcripts. The lengths of the runoff transcripts were analyzed by gel electrophoresis under denaturing conditions. On the basis of the map locations of the restriction sites and the lengths of the runoff transcripts, the in vivo initiation sites were determined. Two major initiation sites having similar activities were thus identified at residues 201 +/- 5 and 2005 +/- 5; both of them were preceded by a TATAA sequence. When uncleaved viral transcriptional complexes or isolated nuclei were incubated in vitro in the presence of [alpha-32P]UTP or [alpha-32P]CTP, they synthesized labeled RNA that, as determined by polyacrylamide gel electrophoresis, contained a major band of 142 nucleotides. The RNA of the major band was mapped between the initiation site at residue 201 +/- 5 and residue 342. We noticed the potential of forming two mutually exclusive stem-and-loop structures in the 142-nucleotide RNA; one of them is followed by a string of uridylic acid residues typical of a procaryotic transcription termination signal. We propose that, as in the transcription of simian virus 40, RNA transcription in minute virus of mice may be regulated by attenuation and may involve eucaryotic polymerase B, which can respond to a transcription termination signal similar to that of the procaryotic polymerase.

The importance of nitric oxide (NO) and dilator prostaglandins in uterine resistance arterioles was investigated. In pentobarbital anaesthetized rats at dioestrus-2, the uterine microcirculation in vivowas transilluminated by a fibreoptic probe and microvessels (circumferential arterioles) viewed by video microscopy. Arteriolar diameters were measured while increasing concentrations of acetylcholine (ACh), serotonin (5-HT), phenylephrine (PE), or angiotensin II (AII) were applied topically (suffused) over the uterus. Agonists were applied alone or with ibuprofen (IBU; cyclooxygenase inhibitor), Nω-nitro-l-arginine (l-NA; nitric oxide synthase inhibitor) or both. Circumferential arterioles were dilated by ACh and 5-HT (10−8–10−4mol l−1) and constricted by PE (10−8–10−5mol l−1) and AII (10−11–10−7mol l−1). Suffusion of l-NA or l-NA with ibuprofen (10−4mol l−1each) abolished ACh-induced dilation; ibuprofen alone blocked dilation at higher ACh concentrations. Serotonin-induced relaxation was significantly attenuated by l-NA alone or in combination with ibuprofen. Vasoconstriction induced by PE was enhanced by l-NA alone and l-NA with ibuprofen, but ibuprofen alone had no effect. In contrast, AII-induced constriction was enhanced significantly by ibuprofen or l-NA and further enhanced when both ibuprofen and l-NA were present. These results suggest that ACh can release either nitric oxide (NO) or cyclooxygenase products to cause uterine arteriolar dilation and that 5-HT-induced uterine microvascular relaxation is mediated via NO only. They also suggest that PE-induced vasoconstriction is attenuated by the release of NO but not cyclooxygenase products and that constrictor responses evoked by AII are attenuated by both NO and dilator prostaglandin release. Thus, both nitric oxide and dilator prostaglandins are important in the control of uterine microvessels.

We have previously reported that a block of transcription elongation is functioning in vivoand in vitrowithin the leader sequences of SV40 and the adenovirus 2 major late transcription units and in the regulation of transcription of the P4 promoter of minute virus of mice. In the present study using the HeLa whole cell extract-Sarkosyl system with adenovirus 2 major late promoter as a template we have analyzed several basic parameters that can contribute to our understanding of the mechanism that regulates the elongation block at the adenovirus 2 attenuation site. We show that the elongation block is augmented at elevated temperatures (40–45 °C). The elongation block can be reversed by the addition of 0.2 MNaCl to the transcription reaction and the reversibility is temperature-dependent. Furthermore, while at 30–35 °C the elongation block is reversible with dilution of the Sarkosyl, at 40–45 °C it is only partially reversible. These results may indicate that a factor(s) is involved in the regulation of the elongation block and/or that the conformation of the transcription complex is temperature dependent. Finally, we show that the extent of the elongation block is dependent on the consecutive T residues at the attenuation site and we discuss the involvement of RNA secondary structure in eliciting the elongation block.

Homeopathic doctor Eric Asher entertains us with tales of treating his family pets while John Saxton gives the veterinary perspective. [ABSTRACT FROM AUTHOR]

Moths of the genus Celerio, hovering and feeding from blossoms, have been observed to react vigorously to high-pitched sounds. The acoustic receptor appears to involve the labial palps. Its characteristics have been determined from responses made, when the moth is exposed to artificial sound pulses, by an interneuron originating in its head. These responses have been found only in 4 out of 19 sphingid species tested.

Two cases of apparent failure to respond to well-indicated homeopathic treatment are presented in a case of nephrotic syndrome, there was dramatic response to exclusion of food of bovine origin.

During the course of experiments previously reported1a male cat was prepared with an extensive bilateral lesion probably involving the left side of the eighth cervical segment and the right side of the first thoracic segment of the spinal cord. The lesion was produced on March 26, 1940. At the time of writing, 21 months after the operation, the animal appears to be in excellent condition. Its weight remains constant at about 3.04 kg, which is slightly above the preoperative value. There have been no pressure ulcers. The appetite is good, and although neither micturition nor defecation occurs spontaneously, the output of urine and feces is normal in quantity. Active spermatozoa are produced and are ejaculated in response to appropriate stimulation. Sensory anesthesia and volitional paralysis are apparent below the level of the lesion. Breathing is entirely diaphragmatic. The functional signs are those of complete interruption of the spinal pathways.In addition to the usual spinal reflexes, which appear in this animal with regularity and vigor, there is occasionally exhibited a mass reflex of exceptional character which I have not seen described for laboratory animals. It is often elicited by rubbing the shoulder region in such a way as to evoke the typical scratch reflex. Upon continuation or intensification of the stimulus, the scratch response gives way to a violent flexor spasm of the muscles of the abdomen, which brings the hind feet into a position forward of the head, with the legs slightly abducted. As the flexor spasm begins, the rubbing of the shoulder region is discontinued, and the subsequent events occur without further external stimulation.

Cumulative graphic and tabular records covering a period of 27 years show associations of more than 37 species of mites with some 137 species of moths, chiefly noctuids, collected at light in western Massachusetts. Abundance of mites varied from year to year, with peak incidence for most species in late July and early Aug. Tympanic parasites of the mite genus Dicrocheles were by far the most numerous, with more than 1800 mite-host associations recorded. In 1976 D. scedastes, formerly known from the Old World only, outnumbered the common New World species, D. phalaenodectes; in 1977 the number of D. scedastes was low in comparison with D. phalaenodectes. Dicrocheles and certain other moth mites may be redistributed by annual migrations of their hosts and might prove useful in studying patterns of pest moth migration.

Although phoresy upon insects by larval nematodes is well known (Goodey 1951), their occurrence on mites has seldom been reported. Davydova et al. (1967) found numerous examples on gamasines from the burrows of small mammals and the nests of birds in West Siberia. While they could not determine the species of larval worms, they considered that such phoresy favors the distribution and the completion of the life cycle in forms parasitic upon the vertebrates in the nests or burrows of which the mites were found. Dr. E. W. Baker (personal communication) recalls seeing 1 mite bearing a supposed nematode larva, and remembers the report of a similar finding in a Russian paper published prior to 1954, but could give no further details. I have not located the early Russian report, nor have I made an exhaustive search of the literature for other instances.

Recorded or artificially imitated bat pulses and continuous steady tones selected from the same frequency range were about equally effective in restricting the numbers of atympanate moths taken in an ultrasonic light trap as compared with those taken in a silent trap. Slightly but significantly lower numbers of atympanate microlepidoptera also were taken in the ultrasonic as compared with the silent trap. Among seven steady stimulus tones ranging from 12.5 to 200 kcps., the one showing the greatest effectiveness for moths with thoracic tympana was that at 37.5 kcps. For moths with abdominal tympana, the most effective frequency was 75 kcps.