Parent Mental Health Before and During the COVID-19 Pandemic

Although extant cross-sectional data suggest that parents have experienced numerous challenges (e.g., homeschooling, caregiver burden) and mental health consequences during the COVID-19 pandemic, longitudinal data are needed to confirm mental health changes relative to pre-pandemic levels and identify which specific pandemic-related changes most highly predict mental health during the pandemic. In two longitudinal subsamples (N = 299 and N = 175), we assessed change in anxiety, depression, and stress before and during the pandemic and whether the accumulation of pandemic-related changes predicted observed mental health changes. On average, parents reported increased depression and anxiety, but no significant changes in reported stress. Moreover, increased interpersonal conflict, difficulty managing work and caregiving responsibilities, and increased economic challenges were the types of pandemic-related changes that most strongly predicted worse mental health, highlighting that juggling caregiving responsibilities and economic concerns, along with the pandemic's impact on interpersonal family relationships are key predictors of worsening parental mental illness symptoms.

A miniaturized piezoelectric Mössbauer spectrometer with feedback control

A Mössbauer spectrometer was built and evaluated using an amplified piezoelectric actuator under feedback control for the Doppler velocity drive. The actuator was driven with a quadratic displacement waveform, giving a linear velocity profile. The optimization of the piezoelectric Doppler drive under feedback control was performed with measurements from a laser Doppler vibrometer. 57Fe Mössbauer spectra of α-iron in transmission geometry show minimal peak distortions. The performance of this piezoelectric Doppler drive makes Mössbauer spectrometry possible in applications requiring small size, mass, and low cost.

A New Bipartite Geminivirus (Begomovirus) Causing Leaf Curl and Crumpling in Cucurbits in the Imperial Valley of California

During fall 1998, volunteer watermelons (Citrullus lunatus L. (Thunb.) Matsum. & Nakai) showing leaf curl, crumpling, and yellowing symptoms were found in a commercial honeydew melon (Cucumis melo L. subsp. melo Inodorus group) field in the Imperial Valley of California. The plants were infected with a begomovirus (family Geminiviridae, genus Begomovirus) based on (i) a positive response in squash blots probed with a general begomovirus DNA probe (1) and (ii) amplification of DNA-A (≈1.2 kb) and DNA-B (≈1.4 kb) fragments by polymerase chain reaction (PCR) with degenerate DNA-A (PAL1v1978/PAR1c496) and DNA-B (PBL1v2040/PBR1c970) primers, respectively (3). The DNA-A and -B fragments were cloned and sequenced (GenBank accession nos. AF224760 [DNA-A] and AF224761 [DNA-B]). The DNA-A and -B fragments had a nearly identical (99.5%) common region (CR) of 186 (DNA-A) and 187 (DNA-B) nucleotides, indicating they were from the same begomovirus. Database searches conducted with these sequences revealed no high degree of sequence identity (i.e., >90%) with other begomoviruses, including Squash leaf curl virus (SqLCV [2]) from southern California. The partial AC1 sequence (669 nt) was most identical to Tomato severe leaf curl virus (ToSLCV) from Guatemala (83%) and SqLCV (81%), the partial AV1 sequence (135 nt) was most identical to Tomato golden mosaic virus from Brazil (84%) and SqLCV (81%), and the CR was most identical to Squash yellow mottle virus from Costa Rica (81%), ToSLCV (81%), and SqLCV (77%). The partial BV1 sequence (465 nt) was most identical to Bean calico mosaic virus and SqLCV (72%), and the partial BC1 sequence (158 nt) was most identical to SqLCV (75%). Watermelon seedlings bombarded with a DNA extract from infected watermelon volunteers developed crumpling and distortion symptoms, whereas seedlings bombarded with gold particles alone developed no symptoms. Geminivirus infection in symptomatic seedlings was confirmed by PCR. These results suggest a new begomovirus caused the disease symptoms in the watermelon volunteers. Leaf crumpling and curling symptoms were not observed in spring melons in the Imperial Valley in 1999, but on 2 July and 17 August 1999, cantaloupe (C. melo L. subsp. melo Cantalupensis group), muskmelon (C. melo L. subsp. melo Cantalupensis group), and watermelon plants with leaf crumpling and yellowing were found. These plants were infected with the new begomovirus based on sequence analysis of PCR-amplified DNA-A fragments (97 to 98% identity for CR and partial AC1 sequence). A survey of fall melons, conducted 23 to 24 September 1999, revealed widespread symptoms of leaf curl and crumpling on new growth of muskmelon plants in all seven commercial fields examined (estimated incidence 25 to 50%) and on watermelon volunteers. No such symptoms were observed on leaves of honeydew melons. Symptomatic muskmelon and watermelon leaves, collected from eight locations throughout the Imperial Valley, were infected with the new begomovirus based on sequence analysis of PCR-amplified DNA-A fragments. Thus, a new begomovirus has emerged in the Imperial Valley; the name Cucurbit leaf crumple virus (CuLCrV) is proposed. References: (1) R. L. Gilbertson et al. Plant Dis. 75: 336, 1991. (2) S. G. Lazarowitz and I. B. Lazdins. Virology 180:58, 1991. (3) M. R. Rojas et al. Plant Dis. 77:340, 1993.

RESPONSIVE-TO-ANTAGONIST1, a Menkes/Wilson disease-related copper transporter, is required for ethylene signaling in Arabidopsis

Ethylene is an important regulator of plant growth. We identified an Arabidopsis mutant, responsive-to-antagonist1 (ran1), that shows ethylene phenotypes in response to treatment with trans-cyclooctene, a potent receptor antagonist. Genetic epistasis studies revealed an early requirement for RAN1 in the ethylene pathway. RAN1 was cloned and found to encode a protein with similarity to copper-transporting P-type ATPases, including the human Menkes/Wilson proteins and yeast Ccc2p. Expression of RAN1 complemented the defects of a ccc2delta mutant, demonstrating its function as a copper transporter. Transgenic CaMV 35S::RAN1 plants showed constitutive expression of ethylene responses, due to cosuppression of RAN1. These results provide an in planta demonstration that ethylene signaling requires copper and reveal that RAN1 acts by delivering copper to create functional hormone receptors.

Subtle neurological deficits and psychopathological findings in substance-abusing homeless and non-homeless veterans

This study evaluated the hypothesis that homeless individuals would display higher levels of neurological deficits than non-homeless individuals, particularly in frontal lobe or executive functions. Eighteen acutely homeless, 15 chronically homeless, and 20 non-homeless individuals admitted to an inpatient psychiatric service received a battery of neurological and psychosocial measures. In comparison to non-homeless subjects with comparable levels of psychopathology, homeless individuals showed higher levels of hostility, prior criminal activity, and family history of psychiatric illness, but lower levels of depression. A positive relationship between hostility and neurological soft signs was observed among chronically homeless subjects. These results suggest that a substantial subset of nonpsychotic homeless veterans suffers from "occult" neurological deficits.

First Report of Bean Common Mosaic Necrosis Potyvirus (BCMNV) Infecting Common Bean in California

During the 1996 growing season (June to September) an outbreak of bean common mosaic was detected in a navy bean field (cv. Snow Bunting) in Colusa County, CA. Early field inspections (August 1996) revealed an incidence of 5 to 10% infection, whereas a late field inspection (September) showed an incidence of 70 to 90% infection. Enzyme-linked immunosorbent assay (ELISA) was performed on 18 leaf samples from symptomatic plants collected from this field with two monoclonal antibodies (Mab): Mab I-2, which detects bean common mosaic necrosis virus (BCMNV) strains (previously necrotic or serotype A bean common mosaic potyvirus [BCMV] strains), and Mab 197, which detects BCMV strains (previously non-necrotic or serotype B BCMV strains) and BCMNV (3). ELISA results indicated BCMNV infection in all 18 samples. In order to confirm ELISA results and to further characterize the viral isolate(s), primary leaves of the differential bean cvs. Black Turtle Soup (BTS) T-39, Topcrop, Amanda, and Sutter Pink were inoculated mechanically with sap prepared from the same leaves used for ELISA. Within 1 week, BTS T-39 and Topcrop plants showed necrotic spots on inoculated leaves and systemic necrosis and death (black root rot symptoms), Sutter Pink showed typical systemic mosaic symptoms, and Amanda showed necrotic spots and restricted vein necrosis on inoculated leaves. These reactions were consistent with infection by the NL-3 strain of BCMNV (1). Reverse transcriptase-polymerase chain reaction was used to amplify a portion of the genome of the virus that contains the 3' end of the coat protein (CP) gene and the 3' untranslated region (UTR). A DNA fragment of approximately 670 bp was amplified and DNA sequence analysis revealed that the nucleotide sequences of the 3' end of the CP and the UTR region of the California BCMNV isolate were 98 and 94% similar to those of the Michigan isolate of the BCMNV NL-3 strain (2), respectively. Together, these results suggest that the outbreak of bean common mosaic in the cv. Snow Bunting navy beans was caused by a pathogroup VI BCMNV isolate, and DNA sequence information suggests that it is similar to the NL-3 strain of BCMNV. This is the first report of BCMNV in California. References: (1) E. Drijfhout et al. Neth. J. Plant Pathol. 84:13, 1978. (2) G. F. Fang et al. Virus Res. 39:13, 1995. (3) G. I. Mink et al. Arch. Virol. S:397, 1992.

Partial Characterization of Two Whitefly-Transmitted Geminiviruses Infecting Tomatoes in Venezuela

Whitefly-transmitted geminiviruses can cause significant yield losses on tomatoes (Lycopersicon esculentum Mill.) in Venezuela. To identify the geminivirus(es) infecting tomatoes in Venezuela, 20 tomato samples from commercial tomato fields in four states and one weed (Euphorbia heterophylla L.) sample were examined for geminivirus infection. All samples showed symptoms generally associated with geminivirus infection, including golden or yellow mosaic, mottling, crumpling and/or distortion of leaves, and, in some cases, stunted and distorted growth. Through the use of squash blot hybridization analysis and a general probe for Western Hemisphere whitefly-transmitted geminiviruses (4), geminivirus nucleic acids were detected in 19 of 20 tomato samples and the weed sample. No samples were infected with tomato yellow leaf curl virus (TYLCV), based on squash blot hybridization analysis with a TYLCV-specific probe. With polymerase chain reaction (PCR) and degenerate primers for whitefly-transmitted geminiviruses (PAL1v1978 and PAR1c496) (4), an approximately 1.2-kb DNA-A fragment was amplified from the 19 squash blot-positive tomato samples and from the weed sample. No DNA fragment was amplified from any samples when TYLCV-specific primers (PTYC1v2406 and PTYIRc287) (3) were used. PCR-amplified DNA-A fragments from four samples representing four different states [Monagas (5L), Guarico (3M), Aragua (3R), and Portuguesa (2U)] were cloned and sequenced. Partial AC1, AV1, and complete common region (CR) sequences of the 5L, 3M, and 2U DNA-A fragments were 92 to 93, 93, and 95 to 97% identical, respectively, indicating that these were DNA-A clones of the same virus. Furthermore, these sequences were 91 to 92, 92 to 95, and 93 to 95% identical, respectively, to sequences of homologous regions of potato yellow mosaic virus (PYMV), indicating that these tomato-infecting geminiviruses are isolates or strains of PYMV. The partial AC1, AV1, and complete CR sequences of the 3R DNA-A fragment were 79, 95, and 77% identical to those of 5L, 3M, and 2U clones, respectively, suggesting that this is a different geminivirus. These sequences were 75 to 87, 82 to 88, and 73 to 81% identical, respectively, to sequences of homologous regions of other tomato geminiviruses, including tomato golden mosaic from Brazil, tomato mottle from Florida, and tomato leaf crumple from Mexico. The bipartite nature of the geminiviruses that were present in the 5L, 3M, 3R, and 2U samples was suggested by the amplification of a DNA-B fragment with degenerate DNA-B primers (PBL1v2040 and PCRc1) (4). These results suggest at least two distinct bipartite Western Hemisphere whitefly-transmitted geminiviruses are associated with tomato virus diseases in Venezuela, and that one of these (sample 3R) may be an undescribed geminivirus. The sequence of the DNA-A fragment from the weed sample was not closely related to the tomato-infecting geminiviruses and, therefore, this weed was not an alternate host of these viruses. Furthermore, because PYMV has been shown to infect tomatoes and cause yellow mosaic symptoms (1), it would be of interest to determine the relationship of PYMV and tomato yellow mosaic geminivirus (ToYMV), which has been reported infecting tomatoes in Venezuela (2), but has not been characterized on the molecular level. References: (1) A. K. Buragohain et al. J. Gen. Virol. 75:2857, 1994. (2) R. C. de Uzcátegui and R. Lastra. Phytopathology 68:985, 1978. (3) M. K. Nakhla et al. Phy-topathol. Mediterr. 32:163, 1993. (4) M. R. Rojas et al. Plant Dis. 77:340, 1993.

Localization of alpha 7 nicotinic receptor subunit mRNA and alpha-bungarotoxin binding sites in developing mouse somatosensory thalamocortical system

Previous studies in rat, showing a transient pattern of expression of the alpha 7 nicotinic acetylcholine receptor in the ventrobasal thalamus and barrel cortex during the first 2 postnatal weeks, suggest that these receptors may play a role in development of the thalamocortical system. In the present study, in situ hybridization and radiolabeled ligand binding were employed to examine the spatiotemporal distribution of alpha 7 mRNA and alpha-bungarotoxin binding sites in the thalamocortical pathway of mouse during early postnatal development. As in the rat, high levels of alpha 7 mRNA and alpha-bungarotoxin binding sites are present in the barrel cortex of mouse during the first postnatal week. Both alpha 7 mRNA and its receptor protein are observed in all cortical laminae, with the highest levels seen in the compact cortical plate, layer IV, and layer VI. When viewed in a tangential plane, alpha 7 mRNA and alpha-bungarotoxin binding sites delineate a whisker-related barrel pattern in layer IV by P3-5. Quantitative analysis reveals a dramatic decrease in the levels of expression of alpha 7 mRNA and alpha-bungarotoxin binding sites in the cortex by the end of the second postnatal week. Unlike in the rat, only low levels of alpha 7 mRNA or alpha-bungarotoxin binding sites are present in the ventrobasal complex of the mouse thalamus. The broad similarities between the thalamocortical development of rat and mouse taken together with the present results suggest that alpha 7 receptors located on cortical neurons, rather than on thalamic neurons, play a role in mediating aspects of thalamocortical development.

Transcription of a bacteriophage lambda DNA site blocks growth of Escherichia coli

The rap mutation in Escherichia coli prevents the growth of bacteriophage lambda. Phage mutations that overcome rap inhibition (bar) have been mapped to loci in the pL operon. We cloned and sequenced three mutations in two of these loci: barIa to the left arm of the lambda attachment site (attP) and barII in the ssb (ea10) gene. The mutations represent single base-pair changes within nearly identical 16-base-pair DNA segments. Each mutation disrupts a sequence of dyad symmetry within the segment. Plasmids carrying a bar+ sequence downstream to an active promoter are lethal to rap, but not rap+, bacteria. The bar sequences isolated from the lambda bar mutants are not lethal. We synthesized a minimal lambda barIa+ sequence, 5'-TATATTGATATTTATATCATT, and cloned it downstream to an inducible promoter. When transcribed, this sequence is sufficient to kill a rap strain.

Radiosensitization by derivatives of isoindole-4,7-dione

New derivatives of isoindole -4,7-dione have been synthesized and their radiation sensitization and chemical behavior have been studied. One-electron reduction potentials have been determined by pulse radiolysis and found to be in the range of -0.45 to -0.36 V vs NHE . Radiosensitization effects were tested in vivo using soft tissue sarcoma transplanted in mice. All the isoindole -4,7-diones tested were found to exert considerable radiosensitization, approaching that of misonidazole tested under comparable conditions. The derivatives which contain a carbethoxy group on the pyrrolic ring were found to have more positive reduction potentials and to act as more efficient sensitizers. Further development of this class of radiosensitizers is underway.

Effects of coronary arterial pressure on left ventricular end-systolic pressure-volume relation of isolated canine heart

In the excised canine left ventricle, the end-systolic pressure-volume relationship (ESPVR) has been shown to be approximately linear over the working range of loading conditions when coronary arterial pressure (CAP) is maintained constant, independent of loading conditions. To investigate the ESPVR under the more intact physiological condition in which the CAP varies with loading on the left ventricle, we studied the effect of changes in CAP on the ESPVR in 10 excised cross-circulated canine ventricles which were contracting isovolumically. The ESPVR, determined from isovolumic contractions at four different volumes, was reasonably independent of CAP as long as CAP remained above a critical pressure (67.0 +/- 22.1 mm Hg). Below this pressure, the slope of ESPVR decreased although the volume axis intercept (V0) remained unaltered. These findings indicate that under physiological conditions, where there is a close coupling of CAP to systolic left ventricular pressure, the ESPVR should become nonlinear in the low preload or afterload regions. When CAP was varied with the left ventricular pressure in five ventricles, the ESPVR indeed became nonlinear in the low-load region. We conclude that the ESPVR in intact conditions is reasonably linear in the physiological load range, but it can be nonlinear in the low-load range.

Ventricular size and shape by two-dimensional echocardiography

The evaluation of cardiac size and shape has been aided by the recent development of high resolution real-time two-dimensional echocardiography, which permits dynamic cross-sectional evaluation of all or a large portion of the left ventricle throughout the cardiac cycle. This review addresses itself to the determination of left ventricular size and shape by two-dimensional echocardiography. A method is described for accurate volume determination in the intact, isolated, ejecting canine heart. By combining the two-dimensional echocardiogram with knowledge of transducer position and orientation with respect to the heart, it is possible to reconstruct a three-dimensional representation of a chamber and thereby measure volume without reliance on major geometric assumptions. Because of the unique ability of two-dimensional echocardiography to produce a cross-sectional image of the beating heart in a large number of planes, it is suitable for the determination of cardiac shape and architecture. The recognition of early regional cardiac dilatation in acute myocardial infarction is described. Changes in ventricular shape brought about by the dynamic alterations lend themselves well to two-dimensional echocardiographic study. The pivotal nature of the interventricular septum renders it susceptible to changes in the functional state of both ventricles. That the interventricular septum may mediate ventricular interaction acutely is suggested by the acute effects of right ventricular loading in man using the Mueller maneuver. Leftward septal displacement and flattening of the septum during the early maximal Mueller maneuver is evidenced by a substantial increase in the radius of curvature of the septal segment, without a change in the left ventricular free wall. This septal flattening occurs in diastole and persists during systole. Diastolic events thus appear to influence systolic shape. Changed septal shape may be an important mechanism of, and evidence for, ventricular interdependence in normal man.