Erratum to: Further analysis of selection-based instruction, lag reinforcement schedules, and the emergence of topography-based responses to interview questions.

[This corrects the article DOI: 10.1007/s40616-015-0031-5.].

Expression of a magainin-type antimicrobial peptide gene (MSI-99) in tomato enhances resistance to bacterial speck disease.

MSI-99 is a synthetic analog of magainin II (MII), a small cationic peptide highly inhibitory to a wide spectrum of microbial organisms. Tomato plants were transformed to express a gene encoding the MSI-99 peptide and tested for possible enhancement of resistance to important pathogens of this crop. Thirty-six tomato transformants carrying an MSI-99 expression vector designed to target the peptide into extracellular spaces were obtained by Agrobacterium tumefaciens-mediated transformation. Expression of MSI-99 caused no obvious cytotoxic effects in these plants. In the tests with Pseudomonas syringae pv. tomato (bacterial speck pathogen) at 10(5 )CFU/ml, several MSI-99-expressing lines developed significantly fewer disease symptoms than controls. However, MSI-99-expressing lines were not significantly different from controls in their responses to the fungal pathogen Alternaria solani (early blight) and the oomycete pathogen Phytophthora infestans (late blight). These findings are in accordance with our previous in vitro inhibition tests, which showed that the MSI-99 peptide is more inhibitory against bacteria than against fungi and oomycetes. Additional in vitro inhibition assays showed that MSI-99 loses its antimicrobial activity in the total or extracellular fluids from leaflets of non-transformed tomato plants; however, P. syringae pv. tomato could not multiply in the extracellular fluid from an MSI-99-expressing line. Our results suggest that expression strategies providing continuous high expression of MSI-99 will be necessary to achieve significant enhancement of plant disease resistance.

Modification of the in vivo four-point loading model for studying mechanically induced bone adaptation.

We modified the noninvasive, in vivo technique for strain application in the tibiae of rats (Turner et al., Bone 12:73-79, 1991). The original model applies four-point bending to right tibiae via an open-loop, stepper-motor-driven spring linkage. Depending on the magnitude of applied load, the model produces new bone formation at periosteal (Ps) or endocortical surfaces (Ec.S). Due to the spring linkage, however, the range of frequencies at which loads can be applied is limited. The modified system replaces this design with an electromagnetic vibrator. A load transducer in series with the loading points allows calibration, the loaders' position to be adjusted, and cyclic loading completed under load control as a closed servo-loop. Two experiments were conducted to validate the modified system: (1) a strain gauge was applied to the lateral surface of the right tibia of 5 adult female rats and strains measured at applied loads from 10 to 60 N; and (2) the bone formation response was determined in 28 adult female Sprague-Dawley rats. Loading was applied as a haversine wave with a frequency of 2 Hz for 18 sec, every second day for 10 days. Peak bending loads were applied at 33, 40, 52, and 64 N, and a sham-loading group was included at 64 N. Strains in the tibiae were linear between 10 and 60 N, and the average peak strain at the Ps.S at 60 N was 2664 +/- 250 microstrain, consistent with the results of Turner's group. Lamellar bone formation was stimulated at the Ec.S by applied bending, but not by sham loading. Bending strains above a loading threshold of 40 N increased Ec lamellar bone formation rate, bone forming surface, and mineral apposition rate with a dose response similar to that reported by Turner et al. (J Bone Miner Res 9:87-97, 1994). We conclude that the modified loading system offers precision for applied loads of between 0 and 70 N, versatility in the selection of loading rates up to 20 Hz, and a reproducible bone formation response in the rat tibia. Adjustment of the loader also enables study of mechanical usage in murine tibia, an advantage with respect to the increasing variety of transgenic strains available in bone and mineral research.

Stable transformation of tomato cell cultures after bombardment with plasmid and YAC DNA.

Stable transformants were obtained after microprojectile particle bombardment of tomato cell suspensions (Lycopersicon esculentum cv VFNT Cherry and L. pennellii). The suspensions were bombarded with tungsten particles coated with either plasmid (∼6.3 kb) or yeast artificial chromosome (YAC) (80 kb) DNA containing the ß-glucuronidase (GUS) and neomycin phosphotransferase II (nptII) genes. The YAC DNA contained an insert of approximately 50 kb of DNA from VFNT Cherry. L. pennellii suspensions were more amenable to transformation than VFNT Cherry; more kanamycin-resistant calli were recovered from L. pennelli after bombardment with plasmid DNA, and only L. pennellii cells produced transformants after bombardment with YAC DNA. DNA gel blot analysis confirmed the presence of the nptll and GUS genes. This analysis also confirmed the integration of YAC DNA into the genome of the kanamycin-resistant calli and suggested that the level of intactness of the integrated YAC DNA was fairly high in four of the five transformants examined. Microprojectile bombardment of regenerable cultures with YACs may ultimately aid in map-based cloning of agriculturally-important genes.

A microcomputer system for physiological data collection and analysis.

The ability to monitor and record activity within the masticatory system is of importance to both general practitioner and research worker. Recent developments in physiological data collection and analysis at the Department of Anatomy, University of Queensland, have achieved that objective in a simple and cost-effective manner. Recording, printing, plotting, and a wide range of analysis procedures can be undertaken utilizing relatively inexpensive available computers.

Functional in vivo analyses of the 3' flanking sequences of the Chlamydomonas chloroplast rbcL and psaB genes.

Possible roles of untranslated sequences at the 3' ends of chloroplast genes, which include inverted repeat elements, were investigated in Chlamydomonas reinhardtii in vivo. Chlamydomonas chloroplast rbcL or psaB 3' flanking regions were coupled in various arrangements 3' to a chimeric gene consisting of a Chlamydomonas chloroplast atpB promoter sequence fused 5' to the Escherichia coli uidA (GUS) structural gene. These genes were introduced into the Chlamydomonas chloroplast genome at the same location by homologous recombination following microprojectile bombardment. Transformants harboring chimeric GUS genes fused to rbcL or psaB gene 3' inverted repeat sequences in their normal forward orientations accumulated GUS transcripts of a single size, whereas GUS transcripts of heterogenous sizes accumulated in transformants harboring the same gene lacking an inverted repeat sequence at its 3' end. Thus, the 3' flanking regions of the rbcL and psaB genes can define the location of the 3' terminus of a transcript in vivo. In chloroplast transformants harboring chimeric GUS genes fused to multiple inverted repeat sequences in their normal forward orientations, only GUS transcripts accumulated that were terminated by the first inverted repeat sequence. The latter data suggest that the 3' ends of these RNAs are the products of either transcription termination or endonucleolytic cleavage. Analyses of GUS transcripts in transformants harboring GUS genes terminated by rbcL or psaB gene 3' flanking regions in reversed orientations indicate that transcript 3' end formation in vivo requires nucleotide sequences located outside the inverted repeat elements. Inasmuch as decay rates of GUS transcripts were found to be independent of the presence of a 3' inverted repeat sequence, RNA stabilization does not appear to be a major in vivo function of these elements in the Chlamydomonas chloroplast transcripts studied.

Construction of expression vectors based on the rice actin 1 (Act1) 5' region for use in monocot transformation.

It has been previously reported that the 5' region of the rice actin 1 gene (Act1) promoted high-level expression of a beta-glucuronidase reporter gene (Gus) in transformed rice cells. In this paper we describe the construction of Act1-based expression vectors for use in monocot transformation. As part of the development of these vectors, we have evaluated the influence of the Act1 first intron, the Act1-Gus junction-encoded N-terminal amino acids, and the sequence context surrounding the Act1 and Gus translation initiation site on Act1-Gus gene expression in rice and maize cells. We have found that addition of Act1 intron 1 to the transcription unit of a Gus reporter gene under control of the cauliflower mosaic virus (CaMV) 35S promoter stimulated GUS activity more than 10-fold in transformed rice cells. Optimization of the sequence context around the Gus translation initiation site resulted in a 4-fold stimulation of Gus expression in transformed rice cells. By utilizing both the Act1 intron 1 and optimized Gus translation initiation site, a 40-fold stimulation in Gus expression from the CaMV 35S promoter has been achieved in transformed rice cells; very similar results were obtained in transformed maize cells. Taken together these results suggest that the Act1-based expression vectors described here should promote the expression of foreign genes in most, if not all, transformed monocot cells to levels that have not previously been attainable with alternative expression vectors.

Stable transformation of sorghum cell cultures after bombardment with DNA-coated microprojectiles.

Cells from a suspension culture of Sorghum vulgare (sorghum) have been transformed to either hygromycin or kanamycin resistance following uptake of pBC1 or pNGI plasmids, respectively, introduced on DNA-coated high velocity microprojectiles. Hygromycin- and kanamycin-resistant transformants contained hygromycin B phosphotransferase- and neomycin phosphotransferasehybridizing restriction fragments of the expected size, respectively. A second introduced, but unselected for, reporter uidA gene which encodes ß-glucuronidase activity was also detected by DNA gel blot analysis in these transformants and shown to be expressed at low levels in two of the ten transformants analyzed. Transcripts from the introduced foreign genes accumulated to detectable levels in only these two transformants, both of which had a high copy number of genes integrated into their genome. This report further establishes the biolistic method as a useful route for delivery of DNA into the difficult-to-transform monocotyledonous plant species and represents the first stable transformation of this agronomically-important cereal grain.

Transcriptional analysis of endogenous and foreign genes in chloroplast transformants of Chlamydomonas.

Transcription from modified chloroplast genes has been studied in vitro, but only with the recently developed ability to stably introduce foreign DNA into Chlamydomonas reinhardtii chloroplast chromosomes in situ has it become possible to do so in vivo. Cloned chloroplast DNA sequences, into which had been inserted chimeric genes composed of the GUS coding sequence reporter under transcriptional control of chloroplast promoters for the C. reinhardtii atpA, atpB, and rbcL genes, were introduced into the cells on microprojectiles. These constructs become integrated into chloroplast chromosomes by homologous recombination. RNA gel blot analyses demonstrated that a single major beta-glucuronidase (GUS)-hybridizing transcript accumulates in each chloroplast transformant. We have found that: (1) Transcription of the chimeric gene begins at the same site as in the corresponding endogenous chloroplast gene; (2) the rates of transcription in vivo of the atpA:GUS and atpB:GUS genes relative to one another and to other genes are the same as those for the endogenous atpA and atpB genes, respectively, indicating that these promoters are fully functional despite being fused to a foreign gene and being at an alien location on the chloroplast chromosome; (3) in contrast to the atpA and atpB promoters, the rbcL promoter directs transcription of the rbcL:GUS gene at only 1% of the expected rate, suggesting that other features are required for optimal activity of this promoter; and (4) 22 base pairs upstream of the 5' end of the atpB:GUS transcript in the atpB promoter element is sufficient to confer wild-type levels of promoter activity.

Studies on Chlamydomonas chloroplast transformation: foreign DNA can be stably maintained in the chromosome.

As shown originally by Boynton and co-workers (Boynton, J.E., Gillham, N.W., Harris, E.H., Hosler, J.P., Johnson, A.M., Jones, A.R., Randolph-Anderson, B.L., Robertson, D., Klein, T.M., Shark, K.B., and Sanford, J.C. [1988]. Science 240, 1534-1538), a nonphotosynthetic, acetate-requiring mutant strain of Chlamydomonas reinhardtii with a 2.5-kilobase pair deletion in the chloroplast Bam 10 restriction fragment region that removes the 3' half of the atpB gene and a portion of one inverted repeat can be transformed to photosynthetic competency following bombardment with microprojectiles coated with wild-type Bam 10 DNA. We have found that assorted other circular plasmids, single-strand DNA circles, or linear, duplex DNA molecules containing the wild-type atpB gene can also complement the same mutant. DNA gel blot hybridization analysis of all such transformants indicates that the complementing DNA has integrated into the chromosome at the atpB locus and suggests that a copy-correction mechanism operating between the inverted repeats maintains sequence identity in this region. Sequences from the intact inverted repeat may be recruited to restore the incomplete copy when exogenous DNA with only a portion of the deleted sequence is introduced. Furthermore, a foreign, unselected-for, chimeric gene flanked by chloroplast DNA sequences can be integrated and maintained stably in the chloroplast chromosome. The bacterial neomycin phosphotransferase structural gene fused to the maize chloroplast promoter for the large subunit gene of ribulose-1,5-biphosphate carboxylase (rbcL) has been integrated into the inverted repeat region of the Bam10 restriction fragment. RNA transcripts that hybridize to the introduced foreign gene have been identified.

Effect of ciprofloxacin on intracellular organisms: in-vitro and in-vivo studies.

Ciprofloxacin is taken up rapidly by both human neutrophils and mouse peritoneal macrophages. It does not appear to be bound firmly within the cell and can be eluted readily if the extracellular concentration is lowered. Uptake does not depend on an active transport mechanism. Intracellular ciprofloxacin is biologically active reducing the survival of intracellular Staphylococcus aureus and Mycobacterium fortuitum, in vitro. In vivo, ciprofloxacin was effective in treating a murine systemic infection with an intracellular pathogen Salmonella typhimurium. The progress of infection in sensitive mice with no natural immunity was delayed by ciprofloxacin although at the dosage used the mice were not cured. These results suggested that clinical studies in patients infected by intracellular pathogens are warranted and that ciprofloxacin may have an important role in the treatment of this type of infection.

Ciprofloxacin treatment of systemic salmonella infection in sensitive and resistance mice.

Five days therapy with ciprofloxacin (10 mg/kg bd) starting on day 6 after infection with Salmonella typhimurium, significantly reduced mortality in A/J and CBA mice. In CBA mice ciprofloxacin therapy also resulted in significantly lower viable counts of Salm. typhimurium in the livers and spleens of surviving mice at day 36 than was found in untreated mice or those given chloramphenicol. Ciprofloxacin failed to prevent fatal Salm. typhimurium disease in the majority of Balb/C mice, a strain that has no natural immunity to salmonella infection. Death was delayed in ciprofloxacin-treated mice and ciprofloxacin did control the multiplication of salmonellae in liver and spleen within 3 days of commencement.

Dyskinesias in the geriatric population.

In a population of 500 British geriatric nursing home patients, dyskinesias were assessed using the Abnormal Involuntary Movement Scale. The prevalence of spontaneous dyskinesias was 13.2%, whereas 22.1% of patients receiving neuroleptics medication demonstrated dyskinesias. The frequency was greater in male patients (21.2%) than in female patients (13.2%). Conjoint treatment with antipsychotic and antiparkinsonian medication resulted in the greatest prevalence of abnormal movements (40.6%). The average age of the study population was 82.6 years, and there was no trend for greater frequencies of dyskinesias according to age.

Epidemiology of group B streptococci: one year's experience in an obstetric and special care baby unit.

The epidemiology of group B streptococci (GBS) was studied in an obstetric unit and the related special care baby unit (SCBU). In 1 year 53 (77%) of 69 babies who acquired GBS from their mothers were colonized within 24 h of birth, compared with only 9 (35%) of 38 who acquired GBS from non-maternal sources. While 38 (36%) of 107 GBS colonized babies in the obstetric unit derived the organism from a non-maternal source, the value for the SCBU was only 2 (9%) of 23. In babies rectal and umbilical swabs gave the highest GBS isolation rates. Phage-typing and serotyping suggested that colonized mother baby pairs, rather than staff, were the primary source of hospital acquired GBS. This mode of GBS acquisition did not result in long-term carriage once babies had left hospital. Nosocomial transmission can play an important part in GBS epidemiology, but can be minimized by attention to infection control procedures.

The effect of the beta-adrenoceptor antagonist pindolol on exercise performance.

1 Fifty-two patients who had been treated for essential hypertension for at least 5 years with once-a-day pindolol alone or in combination with a diuretic participated in a strenuous exercise programme. The 24 h antihypertensive efficacy of once-a-day pindolol was shown in blood pressure readings made before the intake of the day's dose. 2 During the first stage of the study before interruption of therapy, pindolol maintained effective blood pressure control and prevented an excessive rise in blood pressure and heart rate following strenuous exercise. 3 Following a 6 week period of interruption of pindolol therapy, higher blood pressure and heart rate levels were reached following exercise. 4 After reintroduction of a single dose of pindolol, improvement in blood pressure control and lower heart rate levels were again seen following exercise. 5 Compared with the period without drug systolic and diastolic blood pressures were lowered to about the same extent at rest and during exercise after maintenance pindolol and after a single dose of pindolol following a 6 week interruption period, but pre-exercise levels rose considerably during the period when therapy was discontinued.

Co-dergocrine (hydergine) in the treatment of tardive dyskinesia.

In a double-blind, placebo-controlled study with co-dergocrine in the treatment of tardive dyskinesia in a group of elderly chronic psychiatric patients the reduction of dyskinetic scores in the group receiving active medication was slightly greater than that in the placebo group; however, this difference did not reach a level of statistical significance. It is suggested that further work could be undertaken with a longer period of treatment, and at a higher dosage level of co-dergocrine, in a younger patient sample.