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1.
Nat Commun ; 6: 5952, 2015 Jan 22.
Article in English | MEDLINE | ID: mdl-25608712

ABSTRACT

High-order harmonic generation in polyatomic molecules generally involves multiple channels of ionization. Their relative contribution can be strongly influenced by the presence of resonances, whose assignment remains a major challenge for high-harmonic spectroscopy. Here we present a multi-modal approach for the investigation of unaligned polyatomic molecules, using SF6 as an example. We combine methods from extreme-ultraviolet spectroscopy, above-threshold ionization and attosecond metrology. Fragment-resolved above-threshold ionization measurements reveal that strong-field ionization opens at least three channels. A shape resonance in one of them is found to dominate the signal in the 20-26 eV range. This resonance induces a phase jump in the harmonic emission, a switch in the polarization state and different dynamical responses to molecular vibrations. This study demonstrates a method for extending high-harmonic spectroscopy to polyatomic molecules, where complex attosecond dynamics are expected.

2.
Phys Rev Lett ; 108(20): 203001, 2012 May 18.
Article in English | MEDLINE | ID: mdl-23003145

ABSTRACT

Recollision processes provide direct insight into the structure and dynamics of electronic wave functions. However, the strength of the process sets its basic limitations--the interaction couples numerous degrees of freedom. In this Letter we decouple the basic steps of the process and resolve the role of the ionic potential which is at the heart of a broad range of strong field phenomena. Specifically, we measure high harmonic generation from argon atoms. By manipulating the polarization of the laser field we resolve the vectorial properties of the interaction. Our study shows that the ionic core plays a significant role in all steps of the interaction. In particular, Coulomb focusing induces an angular deflection of the electrons before recombination. A complete spatiospectral analysis reveals the influence of the potential on the spatiotemporal properties of the emitted light.


Subject(s)
Electrons , Models, Theoretical , Argon/chemistry , Ions/chemistry , Thermodynamics
3.
Physiol Behav ; 96(2): 209-17, 2009 Feb 16.
Article in English | MEDLINE | ID: mdl-18957302

ABSTRACT

Maternal behavior was examined in Flinders Sensitive-Line (FSL) and Wistar-Kyoto (WKY) rats, two different genetic animal models of depression. Behavioral patterns were assessed by undisturbed observations in the nest [Post-Partum Days (PPD) 4 and 9] and post-disturbance observations ("retrieval tests") on PPD 10. Litters were randomly allocated to a mild chronic-stress condition (limiting available bedding between PPD 2 and 9) or a standard rearing condition. The findings indicated that FSL dams did not differ from control dams in the undisturbed observations. However, in the post-disturbance observations FSL dams exhibited less pup-directed behaviors, a shorter latency to first pup carrying/retrieval and more self-directed behaviors than controls (the latter effect only in dams' interaction with whole litter). In contrast, WKY dams performed more pup-directed activities (e.g., nursing and licking) and less self-directed activities in both the undisturbed and post-disturbance observations (in both dams' interaction with single-pup and with the whole-litter) compared to controls. Accordingly, WKY dams exhibited a shorter latency for first pup-licking bout (in both post-disturbance observations). The early life mild chronic-stress used in the study ('limited-bedding') had a minor effect on the dams' behavior. Overall, the study investigated for the first time the maternal behavior of WKY dams and suggests that these dams show an almost opposite behavioral pattern to that of FSL dams. The results are discussed with regard to earlier findings in the FSL strain and behavioral patterns documented in depressed human mothers.


Subject(s)
Depression/genetics , Depression/physiopathology , Maternal Behavior/physiology , Postpartum Period/physiology , Analysis of Variance , Animals , Animals, Newborn , Disease Models, Animal , Female , Maternal Behavior/psychology , Postpartum Period/psychology , Pregnancy , Random Allocation , Rats , Rats, Inbred WKY , Rats, Sprague-Dawley , Rats, Wistar , Reaction Time/physiology , Species Specificity
4.
Behav Brain Res ; 193(1): 94-100, 2008 Nov 03.
Article in English | MEDLINE | ID: mdl-18539346

ABSTRACT

Children of depressed parents exhibit high rates of emotion-dysregulation, characterized by excessive withdrawal or approach strategies toward the mother in infancy. The understanding of factors affecting the establishment of these behavioral deficits is limited. The current study utilized two genetic animal models of depression, the Wistar-Kyoto (WKY) and Flinders Sensitive Line (FSL) rat strains. In addition, in order to assess the interactive effects of depressive vulnerability and exposure to early life stress, the subjects were raised either in a standard rearing condition or exposed to mild chronic-stress on postnatal days (PND) 2-9. On PND 10-11, an isolation test examined the pups' emotion-regulation. WKY pups produced less separation-induced ultrasonic vocalizations (USV) and proximity-seeking behaviors, compared to controls. In addition, WKY pups did not show the expected potentiation effect that was evident in control pups (an increase in USV and pivoting behavior after a short reunion with the dam). FSL pups exhibited less proximity-seeking behaviors compared to controls while showing levels of USV, potentiation of USV, and change in proximity-seeking behaviors that were similar to controls. No differences between the strains were found in self-grooming. The early life chronic-stress paradigm had no effect on the behaviors of the pups, indicating either stress-resilience or a limited effect of the paradigm. Overall, the results tentatively imply a tendency of the WKY and FSL pups towards withdrawal behavior instead of approach-behavior when regulating emotion, with a more pronounced pattern in WKY pups. This behavioral profile is reminiscent of avoidant attachment, a characteristic of many children of depressed parents.


Subject(s)
Behavior, Animal/physiology , Depression/psychology , Social Isolation/psychology , Analysis of Variance , Animals , Anxiety/psychology , Disease Models, Animal , Emotions/physiology , Exploratory Behavior/physiology , Rats , Rats, Inbred Strains , Rats, Inbred WKY , Rats, Sprague-Dawley , Rats, Wistar , Social Environment , Species Specificity , Stress, Psychological/physiopathology
5.
Psychoneuroendocrinology ; 31(9): 1105-16, 2006 Oct.
Article in English | MEDLINE | ID: mdl-16982157

ABSTRACT

Children of depressed parents often exhibit emotion-regulation deficits, characterized by either excessive withdrawal or approach strategies toward the mother. The current study examined behavioral and physiological emotion-regulation in preweanling pups (postnatal day 17-19) belonging to two different genetic animal models of depression, Wistar-Kyoto (WKY) and Flinders Sensitive-Line (FSL) rats. The study also examined the effects of stress on the two animal models, hypothesizing an interactive effect of hereditary vulnerability and exposure to stress. Chronic-stress was simulated by providing limited bedding to the dam and litter for a week, in the early postnatal period. Acute-stress was generated by exposure to an adult male rat, an ethologically valid stressor. Emotion-regulation of the pups was examined using a Y-maze preference test and radioimmunoassay of Hypothalamic-Pituitary-Adrenal (HPA) axis hormones (corticosterone & adreno-corticotropin/ACTH). WKY and FSL pups exhibited reduced approach-behavior toward the dam, an emotion-regulation profile reminiscent of avoidant attachment evident in many children of depressed parents. In contrast, the two animal models did not show similar HPA axis activity. FSL pups exhibited markedly lower ACTH levels compared to controls, while WKY pups did not differ from controls. With regard to the stress manipulations, the limited-bedding condition had no effect, while the acute-stressor induced overall effects on all groups, with more pronounced reactivity evident in the WKY and FSL pups. Taken together, the experiments indicate a similar behavioral profile of the two strains at the preweanling period, while suggesting HPA dysfunction in only one of the strains.


Subject(s)
Adrenocorticotropic Hormone/blood , Behavior, Animal/physiology , Depression/metabolism , Hydrocortisone/blood , Social Behavior , Stress, Psychological/metabolism , Analysis of Variance , Animals , Depression/etiology , Depression/psychology , Disease Models, Animal , Emotions/physiology , Exploratory Behavior/physiology , Female , Male , Object Attachment , Rats , Rats, Inbred Strains , Rats, Inbred WKY , Rats, Sprague-Dawley , Social Environment , Species Specificity , Stress, Psychological/complications
6.
Behav Brain Res ; 167(2): 261-9, 2006 Feb 28.
Article in English | MEDLINE | ID: mdl-16271773

ABSTRACT

Animal models have been used in understanding the neuro-biological basis of depression and predicting successful treatment strategies. The current study focused on two genetic models of depression, the Flinder's Sensitive Line (FSL) and Wister-Kyoto (WKY). Our laboratory showed depressive symptomatology in pre-pubertal WKY and FSL rats, and the current study focused on the strains' anxiety-like traits. Since human depression-anxiety comorbidity is very common at young ages, it is essential to establish whether FSL and WKY pre-pubertal rats also exhibit such comorbidity. In addition, the effect of different rearing environments was studied using a mild chronic-stress condition (limiting available bedding between post-natal days 2-9). Two well-validated tests of anxiety, the open-field and elevated plus-maze, were used on 40-day-old pups. FSL pups exhibited lower anxiety-like behavior when compared to controls, in traditional open-field and plus-maze measures. A different pattern was observed in the WKY strain, which exhibited heightened anxiety-like behaviours in the FSL strain and affecting WKY's body-weight. Overall, the findings indicate differential expression of anxiety in pre-pubertal rats belonging to the 'depressed' strains, suggesting that these strains may be suitable for modelling different sub-groups of depression at young ages.


Subject(s)
Anxiety/complications , Behavior, Animal/physiology , Depression/etiology , Sexual Maturation/physiology , Social Environment , Stress, Psychological/complications , Age Distribution , Analysis of Variance , Animals , Anxiety/psychology , Chronic Disease , Depression/psychology , Disease Models, Animal , Exploratory Behavior/physiology , Rats , Rats, Inbred Strains , Rats, Inbred WKY , Species Specificity
7.
Hum Gene Ther ; 9(5): 649-57, 1998 Mar 20.
Article in English | MEDLINE | ID: mdl-9551613

ABSTRACT

Transduction of MDR1 may be of use in chemoprotection of normal bone marrow (BM) cells during treatment of malignancies, or as a selectable marker for the transfer of other genes into the BM, a critical target for the cure of many diseases. To that aim, the human multidrug resistance gene MDR1 was cloned into an SV40 pseudoviral vector containing the SV40 origin of replication (ori) and encapsidation signal (ses), and the plasmid was encapsidated in COS cells as SV40/MDR1 pseudovirions. Expression of the human MDR1 gene was demonstrated in murine MEL cells infected with SV40/MDR1 pseudovirions, using a monoclonal antibody (MPK16) specific for the human 170-kD P-glycoprotein. Functional P-glycoprotein was demonstrated by resistance to colchicine in NIH-3T3 cells infected with SV40/MDR1 pseudovirions. Activity of P-glycoprotein was assayed by rhodamine-123 dye exclusion and fluorescence-activated cell sorter analysis (FACS) in various cell types including hematopoietic cells. Highly efficient gene transfer and expression was demonstrated in all murine and human cell types tested, including primary human BM cells. Using multiplicities of infection (moi) of 1-2, over 95% of cells were found to become MDR1+. The percent of MDR1+ cells was proportional to the moi. We conclude that the SV40 pseudoviral vector is efficient for gene transmission into human hematopoietic cells.


Subject(s)
Gene Transfer Techniques , Genes, MDR , Genetic Vectors , Hematopoietic Stem Cells , Simian virus 40/genetics , 3T3 Cells , ATP Binding Cassette Transporter, Subfamily B, Member 1/analysis , Animals , COS Cells , Cells, Cultured , Colchicine/pharmacology , Drug Resistance/genetics , Fibroblasts , Hematopoietic Stem Cells/drug effects , Humans , Mice , Plasmids , Polymerase Chain Reaction , Tumor Cells, Cultured
8.
Photochem Photobiol ; 59(4): 491-6, 1994 Apr.
Article in English | MEDLINE | ID: mdl-8022894

ABSTRACT

alpha-Chymotrypsin exhibits photoswitchable activities in an organic solvent after covalent modification of the protein backbone with thiophenefulgide active ester (2). The thiophenefulgide-modified alpha-chymotrypsin exhibits reversible photoisomerizable properties between states (3)-E and (3)-C. The modified alpha-chymotrypsin, where nine lysine residues are substituted by thiophenefulgide units, retains 60% of the activity of the native enzyme. The activities of thiophenefulgide-modified alpha-chymotrypsin toward esterification of N-acetyl-L-phenylalanine (4) by ethanol in cyclohexane are controlled by the configuration of the attached photoisomerizable component and by prior bioimprinting of the protein backbone with the reaction substrate (4). The esterification of (4) in cyclohexane using bioimprinted (3)-C is two-fold faster than in the presence of (3)-E. In the presence of a nonbioimprinted enzyme, esterification of (4) by (3)-C is five-fold faster than with (3)-E. The activity of bioimprinted (3)-E toward esterification of (4) is 4.5-fold higher than that of nonbioimprinted (3)-E. Switchable cyclic esterification of (4) is accomplished by sequential photoisomerization of the thiophenefulgide-modified alpha-chymotrypsin between states (3)-C and (3)-E.


Subject(s)
Chymotrypsin/radiation effects , Chymotrypsin/chemistry , Light , Photochemistry , Solvents
9.
Ann Ophthalmol ; 25(9): 350-2, 1993 Sep.
Article in English | MEDLINE | ID: mdl-8297073

ABSTRACT

A 15-year-old myopic girl had a retinal detachment associated with optic disc coloboma and a macular hole. The retinal detachment was treated successfully with vitrectomy, drainage of the subretinal fluid, and gas tamponade. The possibility of a macular hole should be investigated in myopic eyes with optic disc colobomas and retinal detachments. To the best of our knowledge, such a combination has not been described previously.


Subject(s)
Coloboma/complications , Optic Disk/abnormalities , Retinal Detachment/complications , Retinal Perforations/complications , Adolescent , Female , Fundus Oculi , Humans , Myopia/complications , Retinal Detachment/surgery , Retinal Perforations/surgery , Visual Acuity , Vitrectomy
10.
Br J Ophthalmol ; 76(5): 280-3, 1992 May.
Article in English | MEDLINE | ID: mdl-1356429

ABSTRACT

Out of a total of 2272 diurnal curves (DC) of intraocular pressure (IOP) obtained from 1178 patients 690 first curves of the right eye of all patients were analysed. For each DC there were 4-6 IOP readings taken between 8 am and 6.30 pm of the same day. The patients' diagnosis, age, sex, type of IOP lowering medication, diabetes, and the calendar month of the year were recorded. In 40% of cases the highest IOP was found at the earliest morning measurement with some 65% of peaks occurring before noon. The lowest IOP measurement showed no specific predilection for any particular time of the day. These findings were true for all diagnosis groups. The mean range of IOP fluctuation during the DC was 5.0 mm Hg in normals, 5.8 mm Hg in patients with open angle glaucoma (OAG), and 6.8 mm Hg in patients with ocular hypertension (OHT). Patients treated with timolol had a lower mean IOP fluctuation range than those on other types of IOP lowering treatment. No association was found between all other parameters examined and the diurnal IOP distribution.


Subject(s)
Circadian Rhythm/physiology , Glaucoma, Open-Angle/physiopathology , Intraocular Pressure/physiology , Ocular Hypertension/physiopathology , Adrenergic beta-Antagonists/therapeutic use , Aged , Female , Glaucoma, Open-Angle/drug therapy , Humans , Male , Middle Aged , Ocular Hypertension/drug therapy , Seasons
11.
Eur J Epidemiol ; 6(3): 253-6, 1990 Sep.
Article in English | MEDLINE | ID: mdl-2253728

ABSTRACT

Optimal breast cancer screening includes both physical examination and mammography. In anticipation of the addition of routine mammographic screening to Israel's 25-year-old early breast cancer detection program, we examined the demographic characteristics of almost one thousand women attending a breast cancer screening examination in Tel Aviv for the first time. The specific objective of the survey was to see whether women attending screening were those who stood a good chance of benefiting from it. Only half the women were aged 40 or older, and there was a preponderance of women of Western origin. Almost half had a breast-related complaint at the time of the visit. Targeted public education and appropriate administrative measures are necessary to ensure that women who can benefit from screening attend screening clinics and that clinics are not filled to capacity by women needing diagnostic evaluation and followup rather than routine screening. Tel Aviv general practitioners appeared to be aware of the advantages of breast cancer screening.


Subject(s)
Breast Neoplasms/prevention & control , Mass Screening , Adult , Age Factors , Attitude of Health Personnel , Breast Neoplasms/genetics , Female , Humans , Israel , Mammography , Middle Aged , Self-Examination
12.
Ann Ophthalmol ; 22(8): 312-3, 1990 Aug.
Article in English | MEDLINE | ID: mdl-1699465

ABSTRACT

Congenital insensitivity to pain is a well-defined entity in the group of sensory deficiency syndromes. To the best of our knowledge, unilateral neuroparalytic keratitis associated with congenital insensitivity to pain has not been reported. We report such a case to alert clinicians to this potentially blinding problem.


Subject(s)
Corneal Ulcer/complications , Pain Insensitivity, Congenital/complications , Peripheral Nervous System Diseases/complications , Child, Preschool , Female , Humans , Peripheral Nervous System Diseases/pathology , Sural Nerve/pathology , Tears/metabolism
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