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1.
Transfus Med ; 28(3): 255-260, 2018 Jun.
Article in English | MEDLINE | ID: mdl-28940904

ABSTRACT

OBJECTIVES: The aim of this study was to evaluate the applicability of genotyping of the ABCG2 gene using MALDI-TOF MS and to estimate the allele frequency in the Japanese population. BACKGROUND: Jr (a-) phenotype has a prevalence of approximately 0·05% among Japanese blood donors; DNA-based genotyping was conducted to investigate the molecular basis of the Jr (a-) phenotype along with serological typing. To detect all SNPs of the ABCG2 gene, a high-throughput SNP genotyping platform is needed. METHODS: Overall, 1004 Jr (a-) blood samples were collected from blood donors in Japan and pre-genotyped. To detect the SNPs of the ABCG2 gene using MALDI-TOF MS, polymerase chain reaction and unextend primer were designed. In total, 205 Jr (a-) samples were genotyped using MALDI-TOF MS analysis. RESULTS: The SNPs of 1004 Jr (a-) samples were identified using the HRM analysis and DNA sequencing, and 799 of 1004 (80%) Jr (a-) samples had the homozygous for c.376 T. The designed primers for MALDI-TOF MS perfectly detected the SNPs of the ABCG2 gene. A total of 205 Jr (a-) samples were genotyped using MALDI-TOF MS. Calling failures occurred in only two samples with the mutations c.736CT to c.376C and c.421C to c.421CA. The concordance rate between the pre-genotyped and MALDI-TOF MS-based genotyping results was very high (99·02%) for all ABCG2 alleles. CONCLUSIONS: Jr (a-) Japanese donors had almost the homozygous for c.376 T. However, detections of more than 20 SNPs of the ABCG2 gene for the JR blood group genotyping are needed. MALDI-TOF MS-based genotyping was highly concordant with the pre-genotyped results for all ABCG2 alleles.


Subject(s)
ATP Binding Cassette Transporter, Subfamily G, Member 2/genetics , Genotyping Techniques/methods , Neoplasm Proteins/genetics , Polymorphism, Single Nucleotide , Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization/methods , Asian People , Female , Genotyping Techniques/instrumentation , Humans , Japan , Male
2.
Diabetes Obes Metab ; 17 Suppl 1: 6-11, 2015 Sep.
Article in English | MEDLINE | ID: mdl-26332962

ABSTRACT

The circadian clock mechanism in animals involves a transcriptional feedback loop in which the bHLH-PAS proteins CLOCK and BMAL1 form a transcriptional activator complex to activate the transcription of the Period and Cryptochrome genes, which in turn feed back to repress their own transcription. In the mouse liver, CLOCK and BMAL1 interact with the regulatory regions of thousands of genes, which are both cyclically and constitutively expressed. The circadian transcription in the liver is clustered in phase and this is accompanied by circadian occupancy of RNA polymerase II recruitment and initiation. These changes also lead to circadian fluctuations in histone H3 lysine4 trimethylation (H3K4me3) as well as H3 lysine9 acetylation (H3K9ac) and H3 lysine27 acetylation (H3K27ac). Thus, the circadian clock regulates global transcriptional poise and chromatin state by regulation of RNA polymerase II.


Subject(s)
ARNTL Transcription Factors/genetics , CLOCK Proteins/genetics , Circadian Clocks/genetics , Mammals/genetics , ARNTL Transcription Factors/physiology , Acetylation , Animals , Basic Helix-Loop-Helix Transcription Factors/genetics , CLOCK Proteins/physiology , Gene Expression , Histones/metabolism , Humans , Liver/physiology , Lysine/metabolism , Mice , Models, Biological , RNA Polymerase II/metabolism , Transcription, Genetic
3.
Transfus Med ; 24(1): 39-44, 2014 Feb.
Article in English | MEDLINE | ID: mdl-24152224

ABSTRACT

BACKGROUND: Blood-group genotyping arrays have been widely used in Caucasian and African American populations, but have not been thoroughly tested in Japanese subjects. AIM: To evaluate, using the BLOODchip(®) Reference genotyping system, the concordance of previously typed samples with expected phenotypes and the coverage of the Japanese variants. METHODS: Blood samples from 100 Japanese donors were obtained. DNA was extracted with QIAsymphony (Qiagen, Hilden, Germany). Samples were typed by serological methods and processed with the BLOODchip(®) . When a non-concordant result was identified, further sequencing by polymerase chain reaction-single specific primer (PCR-SSP) was performed. RESULTS: Concordance between systems was 98% (736/751), and 98.8% (742/751) if only non-software-related non-concordances were considered. In the ABO group, 6 'No Call' (NC, inability of the BLOODchip(®) to assign a result) were ascribed to a variant of blood subtype A1 (A102; 467C>T), a common subtype in Asian populations, whereas three NC presented additional polymorphisms not contained in the BLOODchip(®) (A102/A205, A102/O06 and A204/O02). In the RhD group, one discrepancy was correctly genotyped as RHD*1227A (Del phenotype) by the BLOODchip(®) (phenotyped as partial D, RHD*DIVb). Another was phenotyped as D+ by the BLOODchip(®) (phenotyped weak D by serology) and confirmed as RHD*D-CE(2)-D heterozygous by sequencing. The 3 RhD NC can be solved by further software update. For RhCE, one discrepancy was correctly genotyped for both systems; however, only the BLOODchip(®) was able to detect RHCE*CX allele. CONCLUSIONS: By programming the A102 ABO variant into the system software with the new allele combinations, the BLOODchip(®) Reference is a suitable genotyping tool to be applied to Asian samples.


Subject(s)
Blood Group Antigens/genetics , Blood Grouping and Crossmatching , Genotyping Techniques , Adult , Asian People , Blood Group Antigens/blood , Blood Grouping and Crossmatching/instrumentation , Blood Grouping and Crossmatching/methods , Female , Genotyping Techniques/instrumentation , Genotyping Techniques/methods , Humans , Infant, Newborn , Japan , Male , Sensitivity and Specificity
4.
ScientificWorldJournal ; 2014: 476207, 2014.
Article in English | MEDLINE | ID: mdl-24715814

ABSTRACT

Yarrowia lipolytica is a nonpathogenic dimorphic aerobic yeast that stands out due to its ability to grow in hydrophobic environments. This property allowed this yeast to develop an ability to metabolize triglycerides and fatty acids as carbon sources. This feature enables using this species in the bioremediation of environments contaminated with oil spill. In addition, Y. lipolytica has been calling the interest of researchers due to its huge biotechnological potential, associated with the production of several types of metabolites, such as bio-surfactants, γ-decalactone, citric acid, and intracellular lipids and lipase. The production of a metabolite rather than another is influenced by the growing conditions to which Y. lipolytica is subjected. The choice of carbon and nitrogen sources to be used, as well as their concentrations in the growth medium, and the careful determination of fermentation parameters, pH, temperature, and agitation (oxygenation), are essential for efficient metabolites production. This review discusses the biotechnological potential of Y. lipolytica and the best growing conditions for production of some metabolites of biotechnological interest.


Subject(s)
Biotechnology , Yarrowia/physiology , Yarrowia/growth & development , Yarrowia/metabolism
5.
J Hosp Infect ; 146: 160-165, 2024 Apr.
Article in English | MEDLINE | ID: mdl-37301228

ABSTRACT

BACKGROUND: During the COVID-19 pandemic, hygiene awareness was increased in communities and hospitals. However, there is controversy regarding whether such circumstances affected the incidence of surgical site infections (SSIs) in the orthopaedic surgical field. AIM: To examine the impact of the COVID-19 pandemic on the incidence of SSIs after orthopaedic surgery. METHODS: The medical records of patients having undergone orthopaedic surgery were extracted from the nationwide surveillance database in Japan. The primary outcomes were the monthly incidences of total SSIs, deep or organ/space SSIs, and SSIs due to meticillin-resistant Staphylococcus aureus (MRSA). Interrupted time series analysis was conducted between pre-pandemic (January 2017 to March 2020) and pandemic (April 2020 to June 2021) periods. RESULTS: A total of 309,341 operations were included. Interrupted time series analysis adjusted for seasonality showed no significant changes in the incidence of total SSIs (rate ratio 0.94 and 95% confidence interval 0.98-1.02), deep or organ/space SSIs (0.91, 0.72-1.15), or SSIs due to MRSA (1.07, 0.68-1.68) along with no remarkable slope changes in any parameter (1.00, 0.98-1.02; 1.00, 0.97-1.02; and 0.98, 0.93-1.03, respectively). CONCLUSIONS: Awareness and measures against the COVID-19 pandemic did not markedly influence the incidence of total SSIs, deep or organ/space SSIs, or SSIs due to MRSA following orthopaedic surgery in Japan.

6.
J Endocrinol Invest ; 36(10): 853-9, 2013 Nov.
Article in English | MEDLINE | ID: mdl-23665535

ABSTRACT

AIM: The aim of this study was to determine the correlation between the growth hormone (GH)-insulin-like growth factor-I (IGF-I) axis and glucose intolerance in acromegaly during the early postoperative period. SUBJECTS AND METHODS: The study included 20 patients with acromegaly caused by GH-secreting pituitary adenoma who received transsphenoidal surgery in our hospital. Glucose tolerance was evaluated with oral glucose tolerance tests (OGTTs) performed during pre- and early postoperative periods (9 [7-18] days after surgery). Homeostasis model assessment of insulin resistance (HOMA-IR) and insulinogenic index (IGI) were calculated, and correlation analyses were performed between these values and the GH-IGF-I axis. Patients were divided according to postoperative changes of the axis, and glucose tolerance was compared between the groups. RESULTS: In preoperative OGTTs, nine patients had impaired glucose tolerance and two had diabetes mellitus patterns. Postoperatively, significant reduction was observed both in fasting plasma glucose levels (p<0.01) and in HOMA-IR (p<0.01), whereas IGI showed no significant change. HOMA-IR was significantly correlated with serum IGF-I levels both before (r=0.83, p<0.01) and after (r=0.57, p<0.01) surgery, although it was not correlated with serum GH levels. Patients who achieved more than 50% postoperative reduction in serum IGF-I levels showed significant improvement in OGTTs results (p<0.05). CONCLUSIONS: In patients with acromegaly, serum IGF-I levels, but not GH levels, were significantly correlated with insulin resistance. Early postoperative improvement of glucose tolerance is observed in patients who achieved postoperative reduction in serum IGF-I levels.


Subject(s)
Acromegaly/surgery , Biomarkers/blood , Insulin Resistance , Insulin-Like Growth Factor I/analysis , Neurosurgical Procedures , Sphenoid Sinus/surgery , Acromegaly/blood , Acromegaly/etiology , Adult , Aged , Female , Follow-Up Studies , Human Growth Hormone/blood , Humans , Male , Middle Aged , Pituitary Neoplasms/blood , Pituitary Neoplasms/complications , Postoperative Period , Prognosis , Young Adult
7.
Anaerobe ; 22: 137-40, 2013 Aug.
Article in English | MEDLINE | ID: mdl-23792231

ABSTRACT

This study investigated the suppression of in vitro rumen methane (CH4) output by the supernatant of Lactobacillus plantarum TUA1490L. Hydrogen peroxide (H2O2) was detected in the supernatant. Although CH4 output was reduced by 72%, the supernatant had an adverse effect on total volatile fatty acid (VFA) concentration.


Subject(s)
Fatty Acids, Volatile/metabolism , Fermentation/drug effects , Hydrogen Peroxide/metabolism , Hydrogen-Ion Concentration/drug effects , Lactobacillus plantarum/metabolism , Methane/biosynthesis , Rumen/metabolism , Animals , In Vitro Techniques , Livestock
8.
Minerva Stomatol ; 62(1-2): 23-9, 2013.
Article in English | MEDLINE | ID: mdl-23422681

ABSTRACT

AIM: This study evaluated the effect of microwave irradiation as an alternative method for disinfection of different types of denture base acrylic resins. METHODS: Twenty-four samples for each conventional, microwaved and characterized heat-cured acrylic resin were made and subjected to sterilization with ethylene oxide for the groups: 1) irradiated samples; 2) non-irradiated samples; and 3) samples without yeast. Each group was subdivided according to inoculation with C. albicans, C. dubliniensis and C. tropicalis. The samples were inoculated with 100 µL of inoculum of each species of Candida and later placed in an incubator at 37 °C for 1 hr to perform the first adhesion. After this time, each well was supplemented with sterile media and the plate was once again taken to a stove for incubation at 37 °C for 6 hr. The samples were immersed in 100 mL of sterile water and irradiated with microwave at 650 W for 3 min. Control samples were considered as the non-irradiated group. After incubation for 48 hr, irradiated and non-irradiated samples were subjected to a digital colony counter. RESULTS: Control group (non-irradiated) showed microbial growth for resins and the means of ufc/mL were without statistically significant differences. Microwave irradiated samples (experimental group) promoted no viable colonies for all Candida species and types of acrylic resins. The means of ufc/mL were without statistically significant differences. CONCLUSION: Microwave irradiation was an effective method for disinfection of the acrylic resins inoculated with C. albicans, C. dubliniensis and C. tropicalis.


Subject(s)
Acrylic Resins/radiation effects , Candida/radiation effects , Disinfection/methods , Microwaves , Candida/growth & development , Candida albicans/growth & development , Candida albicans/radiation effects , Candida tropicalis/growth & development , Candida tropicalis/radiation effects , Candidiasis/prevention & control , Dental Prosthesis , Equipment Contamination , Ethylene Oxide , Hot Temperature , Humans , Opportunistic Infections/prevention & control , Prosthesis-Related Infections/prevention & control
9.
Heredity (Edinb) ; 109(5): 261-8, 2012 Nov.
Article in English | MEDLINE | ID: mdl-22948186

ABSTRACT

In many eusocial Hymenoptera, a proportion of males are produced by workers. To assess the effect of male production by workers on the effective population size N(e), a general expression of N(e) in Hymenoptera with worker-produced males is derived on the basis of the genetic drift in the frequency of a neutral allele. Stochastic simulation verifies that the obtained expression gives a good prediction of N(e) under a wide range of conditions. Numerical computation with the expression indicates that worker reproduction generally reduces N(e). The reduction can be serious in populations with a unity or female-biased breeding sex ratio. Worker reproduction may increase N(e) in populations with a male-biased breeding sex ratio, only if each laying worker produce a small number of males and the difference of male progeny number among workers is not large. Worker reproduction could be an important cause of the generally lower genetic variation found in Hymenoptera, through its effect on N(e).


Subject(s)
Genetic Variation , Hymenoptera/genetics , Models, Genetic , Animals , Female , Male , Population Density , Reproduction/genetics
10.
Neurol Sci ; 33(2): 453-61, 2012 Apr.
Article in English | MEDLINE | ID: mdl-21822697

ABSTRACT

Moderate to severe migraine attacks are treated with triptans. However, about 25% of migraineurs fail to respond to triptans. We investigated the involvement of gene polymorphisms, personality traits and characteristics of headache, and made a scoring system for prediction of clinical response to triptans in patients with migraine. Gene polymorphisms including serotonin (5-HT)(1B) receptor G861C and dopamine receptor 2 (DRD2) C939T, personality traits and characteristics of headache were investigated in 46 consistent responders and 14 inconsistent responders to triptans. The multivariate stepwise logistic regression analysis revealed that age, periorbital/deep orbital pain and C/C genotype carrier at DRD2 C939T were significant factors that contributed independently to the negative response to triptans in patients with migraine. Their odds ratios were 6.329 (40-69 vs. 20-39 years, 95% CI 1.441-27.778), 6.772 (no vs. yes, periorbital/deep orbital pain, 95% CI 1.159-39.580) and 14.085 (non-C/C vs. C/C genotype at DRD2 C939T, 95% CI 1.253-166.667), respectively. The predictive index (PI) of clinical response to triptans in patients with migraine was calculated using these three factors. The score in inconsistent responders (1.6 ± 0.6) was significantly higher than that in consistent responders (0.8 ± 0.7, P < 0.001). Sensibility of low-score (RI = 0) group was 100%, and specificity of high-score (PI ≥ 2) group was 87%. The proposed scoring system should in the future be the object of larger studies to confirm its validity.


Subject(s)
Migraine Disorders/drug therapy , Tryptamines/therapeutic use , Adult , Age Factors , Aged , Analysis of Variance , Female , Genotype , Humans , Male , Middle Aged , Migraine Disorders/genetics , Migraine Disorders/psychology , Minisatellite Repeats/genetics , Personality/genetics , Personality Inventory , Polymorphism, Genetic/genetics , Predictive Value of Tests , Receptors, Dopamine D2/genetics , Receptors, Serotonin/genetics , Retrospective Studies , Sensitivity and Specificity , Serotonin Antagonists/therapeutic use , Serotonin Plasma Membrane Transport Proteins/genetics , Statistics, Nonparametric , Surveys and Questionnaires , Young Adult
11.
AJNR Am J Neuroradiol ; 43(9): 1279-1285, 2022 09.
Article in English | MEDLINE | ID: mdl-36007950

ABSTRACT

BACKGROUND AND PURPOSE: Choroidal anastomosis, a hemorrhage-prone periventricular collateral manifestation in Moyamoya disease, outflows to the cortex posterior to the central sulcus. The objective of the present study was to test whether the angiographic extent of revascularization posterior to the central sulcus contributes to the postoperative reduction of choroidal anastomosis. MATERIALS AND METHODS: This retrospective cohort study included choroidal anastomosis-positive hemispheres before direct bypass surgery. The postoperative reduction of choroidal anastomosis was determined by a consensus of 2 raters according to the previous research. An imaging software automatically traced the angiographic revascularization area, which was subsequently divided into anterior and posterior parts by an anatomic line corresponding to the central sulcus. Each area was quantitatively measured as a percentage relative to the whole supratentorial area. RESULTS: Postoperative reduction of choroidal anastomosis was achieved in 68 (85.0%) of the 80 included hemispheres. The revascularization area posterior to the central sulcus was significantly larger in the hemispheres with reduction than in those with no reduction (mean, 15.2% [SD, 7.1%] versus 4.2% [SD, 3.4%], P < .001), whereas no significant difference was observed in the revascularization area anterior to the central sulcus. Multivariate analysis revealed that the revascularization area posterior to the central sulcus was the only significant factor associated with reduction (OR, 1.57; 95% CI, 1.21-2.03, for every 1% increase). CONCLUSIONS: The results suggest that a larger revascularization posterior to the central sulcus is associated with postoperative reduction of choroidal anastomosis regardless of the extent of anterior revascularization. It might facilitate optimal selection of the revascularization site for preventing hemorrhage.


Subject(s)
Cerebral Revascularization , Moyamoya Disease , Humans , Moyamoya Disease/diagnostic imaging , Moyamoya Disease/surgery , Moyamoya Disease/complications , Retrospective Studies , Cerebral Angiography , Anastomosis, Surgical/methods , Cerebral Revascularization/methods
12.
New Microbes New Infect ; 44: 100933, 2021 Nov.
Article in English | MEDLINE | ID: mdl-34631109

ABSTRACT

Bacteroides pyogenes is a member of the oral flora of cats and dogs. We report a case of B. pyogenes isolated from an appendiceal abscess in a patient without a history of animal contact. This species was identified by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS) and sequencing of 16S rRNA, rpoB, gyrB and hsp60 genes.

14.
Food Sci Technol Int ; 16(4): 315-20, 2010 Aug.
Article in English | MEDLINE | ID: mdl-21339148

ABSTRACT

The use of fungal and yeast biomass in foodstuff, either as supplements or as major ingredients in formulations is an area of growing interest for the modern food industry. The aim of this study was to evaluate the nutritional potential of biomasses obtained from filamentous fungi Penicillium sclerotiorum, Penicillium janthinellum, Rhizopus stolonifer and Syncephalastrum racemosum. Biomasses presented 26-37% of total proteins, 1.7-3.5% of lipids and 4.6-9.1% of ashes. The humidity level reached 75-83%. Ashes were screened for minerals contents with a special outcome for S. racemosum biomass that presented 3438 mg/100 g (dw) of magnesium. Fatty acids present in the biomasses were screened and the palmitic (C16:0), estearic (C18:0), elaidic (18:1n9-t), oleic (18:1n9-c), linolelaidic (C18:2n6-t), linoleic (C18:2n6-c) and γ-linolenic (C18:3n6) acids were found to be the most abundant, from a total of 88-90% of identified fatty acids. Overall data indicate that the filamentous fungi studied have good nutritional properties, possessing a combination of good level of proteins, low level of fat, and presence of essential fatty acids, including omega-3 derivatives, along with the presence of Ca, Mg, Zn and Fe.


Subject(s)
Fungal Proteins/chemistry , Fungi/chemistry , Lipids/chemistry , Minerals/chemistry , Chromatography , Dietary Supplements , Fungal Proteins/metabolism , Fungi/metabolism , Tropical Climate
15.
Sci Adv ; 6(46)2020 11.
Article in English | MEDLINE | ID: mdl-33188020

ABSTRACT

Neurodegenerative disorders are caused by progressive neuronal loss, and there is no complete treatment available yet. Neuroinflammation is a common feature across neurodegenerative disorders and implicated in the progression of neurodegeneration. Dysregulated activation of microglia causes neuroinflammation and has been highlighted as a treatment target in therapeutic strategies. Here, we identified novel therapeutic candidate ALGERNON2 (altered generation of neurons 2) and demonstrate that ALGERNON2 suppressed the production of proinflammatory cytokines and rescued neurodegeneration in a 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-induced Parkinson's disease model. ALGERNON2 stabilized cyclinD1/p21 complex, leading to up-regulation of nuclear factor erythroid 2-related factor 2 (Nrf2), which contributes to antioxidative and anti-inflammatory responses. Notably, ALGERNON2 enhanced neuronal survival in other neuroinflammatory conditions such as the transplantation of induced pluripotent stem cell-derived dopaminergic neurons into murine brains. In conclusion, we present that the microglial potentiation of the p21-Nrf2 pathway can contribute to neuronal survival and provide novel therapeutic potential for neuroinflammation-triggered neurodegeneration.


Subject(s)
Microglia , Neurodegenerative Diseases , Animals , Disease Models, Animal , Dopaminergic Neurons/metabolism , Mice , Mice, Inbred C57BL , Microglia/metabolism , NF-E2-Related Factor 2/metabolism , Neurodegenerative Diseases/etiology , Neurodegenerative Diseases/metabolism , Neurodegenerative Diseases/therapy , Neuroinflammatory Diseases
16.
Phys Rev Lett ; 103(24): 242301, 2009 Dec 11.
Article in English | MEDLINE | ID: mdl-20366198

ABSTRACT

The effects of fluctuating initial conditions are studied in the context of relativistic heavy ion collisions where a rapidly evolving system is formed. Two-particle correlation analysis is applied to events generated with the NEXSPHERIO hydrodynamic code, starting with fluctuating nonsmooth initial conditions (IC). The results show that the nonsmoothness in the IC survives the hydroevolution and can be seen as topological features of the angular correlation function of the particles emerging from the evolving system. A long range correlation is observed in the longitudinal direction and in the azimuthal direction a double peak structure is observed in the opposite direction to the trigger particle. This analysis provides clear evidence that these are signatures of the combined effect of tubular structures present in the IC and the proceeding collective dynamics of the hot and dense medium.

17.
Science ; 220(4592): 82-4, 1983 Apr 01.
Article in English | MEDLINE | ID: mdl-6298939

ABSTRACT

Forskolin, a highly specific activator of adenylate cyclase, produced both delay and advance phase shifts of the circadian rhythm recorded from the isolated eye of the marine mollusk Aplysia. The phase dependence of the response to forskolin was identical to that with serotonin, which also stimulates adenylate cyclase in the eye. The ability of agents to activate adenylate cyclase in homogenates was correlated with their ability to shift the phase of the circadian oscillator. These results along with earlier findings show that adenosine 3',5'-monophosphate mediates the effect of serotonin on the rhythm and regulates the phase of the circadian pacemaker in the eye of Aplysia.


Subject(s)
Adenylyl Cyclases/physiology , Circadian Rhythm , Adenosine Monophosphate/physiology , Animals , Aplysia/physiology , Circadian Rhythm/drug effects , Colforsin , Cyclic AMP/physiology , Diterpenes/pharmacology , Eye/drug effects , Ocular Physiological Phenomena , Serotonin/pharmacology
18.
Science ; 217(4565): 1104-11, 1982 Sep 17.
Article in English | MEDLINE | ID: mdl-6287576

ABSTRACT

Daily rhythms in many behavioral, physiological, and biochemical functions are generated by endogenous oscillators that function as internal 24-hour clocks. Under natural conditions, these oscillators are synchronized to the daily environmental cycle of light and darkness. Recent advances in locating circadian pacemakers in the brain and in establishing model systems promise to shed light on the cellular and biochemical mechanisms involved in the generation and regulation of circadian rhythms.


Subject(s)
Circadian Rhythm , Animals , Cyclic AMP/physiology , Humans , Light , Pineal Gland/physiology , Supraoptic Nucleus/physiology
19.
Science ; 264(5166): 1724-33, 1994 Jun 17.
Article in English | MEDLINE | ID: mdl-8209253

ABSTRACT

Modern molecular genetic and genomic approaches are revolutionizing the study of behavior in the mouse. "Reverse genetics" (from gene to phenotype) with targeted gene transfer provides a powerful tool to dissect behavior and has been used successfully to study the effects of null mutations in genes implicated in the regulation of long-term potentiation and spatial learning in mice. In addition, "forward genetics" (from phenotype to gene) with high-efficiency mutagenesis in the mouse can uncover unknown genes and has been used to isolate a behavioral mutant of the circadian system. With the recent availability of high-density genetic maps and physical mapping resources, positional cloning of virtually any mutation is now feasible in the mouse. Together, these approaches permit a molecular analysis of both known and previously unknown genes regulating behavior.


Subject(s)
Behavior, Animal , Genetic Techniques , Genetics, Behavioral/methods , Animals , Circadian Rhythm/genetics , Female , Learning , Long-Term Potentiation , Male , Mice , Mice, Inbred Strains , Mice, Knockout , Mutagenesis
20.
Science ; 255(5051): 1581-4, 1992 Mar 20.
Article in English | MEDLINE | ID: mdl-1549784

ABSTRACT

The suprachiasmatic nuclei (SCN) of the hypothalamus comprise the primary pacemaker responsible for generation of circadian rhythms in mammals. Light stimuli that synchronize this circadian clock induce expression of the c-fos gene in rodent SCN, which suggests a possible role for Fos in circadian entrainment. Appropriate light stimuli also induce the expression of jun-B messenger RNA in the SCN of golden hamsters but only slightly elevate c-jun messenger RNA levels. In addition, light increases the amount of a protein complex in the SCN that binds specifically to sites on DNA known to mediate regulation by the AP-1 transcription factor. The photic regulation of both jun-B messenger RNA expression and AP-1 binding activity is dependent on circadian phase: only light stimuli that shift behavioral rhythms induce jun-B and AP-1 expression. Thus, light and the circadian pacemaker interact to regulate a specific set of immediate-early genes in the SCN that may participate in entrainment of the circadian clock.


Subject(s)
Gene Expression Regulation , Genes, jun/physiology , Light , Periodicity , Proto-Oncogene Proteins c-jun/biosynthesis , RNA, Messenger/biosynthesis , Animals , Base Sequence , Cricetinae , Genes, fos/physiology , Molecular Sequence Data , Nucleic Acid Hybridization , RNA Probes , Suprachiasmatic Nucleus/physiology , Time Factors , Transcription, Genetic
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