Neural correlates of mindfulness meditation and hypnosis on magnetic resonance imaging: similarities and differences. A scoping review

BACKGROUND

Mindfulness meditation (MM) and hypnosis practices are gaining interest in mental health, but their physiological mechanisms remain poorly understood. This study aimed to synthesize the functional, morphometric and metabolic changes associated with each practice using magnetic resonance imaging (MRI), and to identify their similarities and differences.

METHODS

MRI studies investigating MM and hypnosis in mental health, specifically stress, anxiety, and depression, were systematically screened following PRISMA guidelines from four research databases (PubMed, Web of Science, Embase, PsycINFO) between 2010 and 2022.

RESULTS

In total, 97 references met the inclusion criteria (84 for MM and 13 for hypnosis). This review showed common and divergent points regarding the regions involved and associated brain connectivity during MM practice and hypnosis. The primary commonality between mindfulness and hypnosis was decreased default mode network intrinsic activity and increased central executive network - salience network connectivity. Increased connectivity between the default mode network and the salience network was observed in meditative practice and mindfulness predisposition, but not in hypnosis.

CONCLUSIONS

While MRI studies provide a better understanding of the neural basis of hypnosis and meditation, this review underscores the need for more rigorous studies.

Blindness increases the risk for hip fracture and vertebral fracture but not the risk for distal radius fracture: a longitudinal follow-up study using a national sample cohort

The risks for hip fracture and vertebral fracture, but not the risk for distal radius fracture, were significantly higher in the blindness group than in the control group with a maximum 12-year follow-up.

PURPOSE

To evaluate the influence of visual impairment on the risk for osteoporotic fractures at common sites: hip, thoracic/lumbar vertebra, and distal radius.

METHODS

This longitudinal follow-up study used a database of a national sample cohort from 2002 to 2013 provided by the Korean National Health Insurance Service. Of a total of 1,125,691 subjects, 3918 patients with visual impairment and age ≥ 50 years were enrolled in a 1:4 ratio; 15,672 control participants were matched for age, sex, income, and region of residence. Stratified Cox proportional-hazards models were used to evaluate the crude and adjusted (for steroid medication, rheumatoid arthritis, depression, osteoporosis, diabetes mellitus, and stroke history) hazard ratios (HRs) for each fracture site. Fracture diagnoses were based on the ICD-10 codes: hip fracture (S720, S721, S722), vertebral fracture (S220, S320), and distal radius fracture (S525).

RESULTS

The HRs for hip and vertebral fracture were significantly higher in the blindness group (adjusted HR = 2.46, p < 0.001 for hip fracture; adjusted HR = 1.42, p = 0.020 for thoracic/lumbar vertebral fracture) than in the matched control group. However, the HR for distal radius fracture was not higher in the blindness group. The HRs for all three fracture sites were not significantly higher in the non-blindness visual impairment group after adjustment.

CONCLUSION

The risks for hip fracture and vertebral fracture were significantly higher in the blindness group. However, the risk for distal radius fracture was not related to visual impairment including blindness.

Correction to: Review of global neurosurgery education: Horizon of Neurosurgery in the Developing Countries

[This corrects the article DOI: 10.1186/s41016-020-00194-1.].

Review of global neurosurgery education: Horizon of Neurosurgery in the Developing Countries

Globally, the discipline of neurosurgery has evolved remarkably fast. Despite being one of the latest medical specialties, which appeared only around hundred years ago, it has witnessed innovations in the aspects of diagnostics methods, macro and micro surgical techniques, and treatment modalities. Unfortunately, this development is not evenly distributed between developed and developing countries. The same is the case with neurosurgical education and training, which developed from only traditional apprentice programs in the past to more structured, competence-based programs with various teaching methods being utilized, in recent times. A similar gap can be observed between developed and developing counties when it comes to neurosurgical education. Fortunately, most of the scholars working in this field do understand the coherent relationship between neurosurgical education and neurosurgical practice. In context to this understanding, a symposium was organized during the World Federation of Neurological Surgeons (WFNS) Special World Congress Beijing 2019. This symposium was the brain child of Prof. Yoko Kato—one of the eminent leaders in neurosurgery and an inspiration for female neurosurgeons. Invited speakers from different continents presented the stages of development of neurosurgical education in their respective countries. This paper summarizes the outcome of these presentations, with particular emphasis on and the challenges faced by developing countries in terms of neurosurgical education and strategies to cope with these challenges.

Electromechanical properties of human osteoarthritic and asymptomatic articular cartilage are sensitive and early detectors of degeneration

OBJECTIVE

To evaluate cross-correlations of ex vivo electromechanical properties with cartilage and subchondral bone plate thickness, as well as their sensitivity and specificity regarding early cartilage degeneration in human tibial plateau.

METHOD

Six pairs of tibial plateaus were assessed ex vivo using an electromechanical probe (Arthro-BST) which measures a quantitative parameter (QP) reflecting articular cartilage compression-induced streaming potentials. Cartilage thickness was then measured with an automated thickness mapping technique using Mach-1 multiaxial mechanical tester. Subsequently, a visual assessment was performed by an experienced orthopedic surgeon using the International Cartilage Repair Society (ICRS) grading system. Each tibial plateau was finally evaluated with μCT scanner to determine the subchondral-bone plate thickness over the entire surface.

RESULTS

Cross-correlations between assessments decreased with increasing degeneration level. Moreover, electromechanical QP and subchondral-bone plate thickness increased strongly with ICRS grade (ρ = 0.86 and ρ = 0.54 respectively), while cartilage thickness slightly increased (ρ = 0.27). Sensitivity and specificity analysis revealed that the electromechanical QP is the most performant to distinguish between different early degeneration stages, followed by subchondral-bone plate thickness and then cartilage thickness. Lastly, effect sizes of cartilage and subchondral-bone properties were established to evaluate whether cartilage or bone showed the most noticeable changes between normal (ICRS 0) and each early degenerative stage. Thus, the effect sizes of cartilage electromechanical QP were almost twice those of the subchondral-bone plate thickness, indicating greater sensitivity of electromechanical measurements to detect early osteoarthritis.

CONCLUSION

The potential of electromechanical properties for the diagnosis of early human cartilage degeneration was highlighted and supported by cartilage thickness and μCT assessments.

Non-destructive electromechanical assessment (Arthro-BST) of human articular cartilage correlates with histological scores and biomechanical properties

OBJECTIVE

The hand-held Arthro-BST™ device is used to map electromechanical properties of articular cartilage. The purpose of the study was to evaluate correlation of electromechanical properties with histological, biochemical and biomechanical properties of cartilage.

METHOD

Electromechanical properties (quantitative parameter (QP)) of eight human distal femurs were mapped manually ex vivo using the Arthro-BST (1 measure/site, 5 s/measure, 3209 sites). Osteochondral cores were then harvested from different areas on the femurs and assessed with the Mankin histological score. Prior to histoprocessing, cores were tested in unconfined compression. A subset of the cores was analyzed with polarized light microscopy (PLM) to assess collagen structure. Biochemical assays were done on additional cores to obtain water content and glycosaminoglycan (GAG) content. The QP corresponding to each core was calculated by averaging all QPs collected within 6 mm of the core center.

RESULTS

The electromechanical QP correlated strongly with both the Mankin score and the PLM score (r = 0.73, P < 0.0001 and r = -0.70, P < 0.0001 respectively) thus accurately reflecting tissue quality and collagen architecture. Electromechanical QP also correlated strongly with biomechanical properties including fibril modulus (r = -0.76, P < 0.0001), matrix modulus (r = -0.69, P < 0.0001), and log of permeability (r = 0.72, P < 0.0001). The QP correlated weakly with GAG per wet weight and with water content (r = -0.50, P < 0.0003 and r = 0.39, P < 0.006 respectively).

CONCLUSION

Non-destructive electromechanical QP measurements correlate strongly with histological scores and biomechanical parameters providing a rapid and reliable assessment of articular cartilage quality.

Improving the accuracy of pre-operative survival prediction in renal cell carcinoma with C-reactive protein

Background:

Validated objective biomarkers are needed for patients with renal cell carcinoma (RCC) to guide patient management and define high-risk populations for follow-up or for therapeutic purposes.

Methods:

Patients undergoing nephrectomy for RCC (n=286 all stages, 84% with conventional clear cell type) were included with a median duration follow-up of 5 years. The prognostic significance of pre-operative haematological and biochemical variables, including C-reactive protein (CRP) values were examined and whether they added additional information to a recently published pre-operative scoring system was determined.

Results:

C-reactive protein was the most significant predictor of overall survival (OS; χ²=50.9, P<0.001). Five-year OS for patients with CRP⩽15 mg l⁻¹vs >15 mg l⁻¹ was 72% (95% CI 65–78%) and 33% (95% CI 23–44%), respectively. Similar results were seen for cancer-specific survival (CSS) and disease-free survival. On multivariate analysis, CRP remained highly significant for CSS (χ²=17.3, P<0.0001) and OS (χ²=9.8, P<0.002), in addition to other pre-operative variables including log of neutrophil/lymphocyte ratio, red blood cell count and white cell count. C-reactive protein was significant in addition to the pre-operative nomogram score (χ²=12.5, P=0.0004 for OS, χ²=16.2, P=0.0001 for CSS and χ²=8.6, P=0.003 for DFS) and was still significant when other pre-operative variables were included.

Conclusion:

C-reactive protein and other haematological and biochemical variables have independent prognostic significance in RCC and may enhance pre-operative scoring systems.

Mapping and Comparative Analysis of QTL for Crown Rust Resistance in an Italian x Perennial Ryegrass Population

ABSTRACT Crown rust (Puccinia coronata f. sp. lolli) is a serious fungal foliar disease of perennial ryegrass (Lolium perenne L.) and Italian ryegrass (L. multiflorum Lam.), which are important forage and turf species. A number of quantitative trait loci (QTL) for crown rust resistance previously were identified in perennial ryegrass under growth chamber or greenhouse conditions. In this study, we conducted a QTL mapping for crown rust resistance in a three-generation Italian x perennial ryegrass interspecific population under natural field conditions at two locations over 2 years. Through a comparative mapping analysis, we also investigated the syntenic relationships of previously known crown rust resistance genes in other ryegrass germplasms and oat, and genetic linkage between crown rust resistance QTL and three lignin genes: LpOMT1, LpCAD2, and LpCCR1. The interspecific mapping population of 156 progeny was developed from a cross between two Italian x perennial ryegrass hybrids, MFA and MFB. Because highly susceptible reactions to crown rust were observed from all perennial ryegrass clones, including two grandparental clones and eight clones from different pedigrees tested in this study, two grandparent clones from Italian ryegrass cv. Floregon appeared to be a source of the resistance. Two QTL on linkage groups (LGs) 2 and 7 in the resistant parent MFA map were detected consistently regardless of year and location. The others, specific to year and location, were located on LGs 3 and 6 in the susceptible parent MFB map. The QTL on LG2 was likely to correspond to those previously reported in three unrelated perennial ryegrass mapping populations; however, the other QTL on LGs 3, 6, and 7 were not. The QTL on LG7 was closely located in the syntenic genomic region where genes Pca cluster, Pcq2, Pc38, and Prq1b resistant to crown rust (P. coronata f. sp. avenae) in oat (Avena sativa L.) were previously identified. Similarly, the QTL on LG3 was found in a syntenic region with oat genes resistant to crown rust isolates PC54 and PC59. This indicates that the ortholoci for resistance genes to different formae speciales of crown rust might be present between two distantly related grass species, ryegrass and oat. In addition, we mapped four restriction fragment length polymorphism loci for three key ryegrass lignin genes encoding caffeic acid-O-methyltransferase, cinnamyl alcohol dehydrogenase, and cinnamoyl CoA-reductase on LG7. These loci were within a range of 8 to 17 centimorgans from the QTL on LG7, suggesting no tight linkage between them. The putative ortholoci for those lignin biosynthesis genes were identified on segments of rice (Oryza sativa L.) chromosomes 6 and 8, which are the counterparts of ryegrass LG7. Results from the current study facilitate understanding of crown rust resistance and its relationship with lignin biosynthesis, and also will benefit ryegrass breeders for improving crown rust resistance through marker-assisted selection.

Chromosomal rearrangements differentiating the ryegrass genome from the Triticeae, oat, and rice genomes using common heterologous RFLP probes

An restriction fragment length polymorphism (RFLP)-based genetic map of ryegrass (Lolium) was constructed for comparative mapping with other Poaceae species using heterologous anchor probes. The genetic map contained 120 RFLP markers from cDNA clones of barley (Hordeum vulgare L.), oat (Avena sativa L.), and rice (Oryza sativa L.), covering 664 cM on seven linkage groups (LGs). The genome comparisons of ryegrass relative to the Triticeae, oat, and rice extended the syntenic relationships among the species. Seven ryegrass linkage groups were represented by 10 syntenic segments of Triticeae chromosomes, 12 syntenic segments of oat chromosomes, or 16 syntenic segments of rice chromosomes, suggesting that the ryegrass genome has a high degree of genome conservation relative to the Triticeae, oat, and rice. Furthermore, we found ten large-scale chromosomal rearrangements that characterize the ryegrass genome. In detail, a chromosomal rearrangement was observed on ryegrass LG4 relative to the Triticeae, four rearrangements on ryegrass LGs2, 4, 5, and 6 relative to oat, and five rearrangements on ryegrass LGs1, 2, 4, 5, and 7 relative to rice. Of these, seven chromosomal rearrangements are reported for the first time in this study. The extended comparative relationships reported in this study facilitate the transfer of genetic knowledge from well-studied major cereal crops to ryegrass.

Induction chemotherapy plus three-dimensional conformal radiation therapy in the definitive treatment of locally advanced non-small-cell lung cancer

PURPOSE

To evaluate our institution's experience using chemotherapy in conjunction with three-dimensional conformal radiation therapy (3D-CRT).

METHODS AND MATERIALS

From 1991 to 1998, 152 patients with Stage III non-small-cell lung cancer (NSCLC) were treated with 3D-CRT at Memorial Sloan-Kettering Cancer Center. A total of 137 patients (90%) were surgically staged with either thoracotomy or mediastinoscopy. The remainder were staged radiographically. Seventy patients were treated with radiation therapy alone, and 82 patients received induction chemotherapy before radiation. The majority of chemotherapy-treated patients received a platinum-containing regimen. Radiation was delivered with a 3D conformal technique using CT-based treatment planning. The median dose in the radiation alone group was 70.2 Gy, while in the combined modality group, it was 64.8 Gy.

RESULTS

The median follow-up time was 30.5 months among survivors. Stage IIIB disease was present in 36 patients (51%) in the radiation-alone group and 57 patients (70%) in the combined-modality group. Thirty-nine patients had poor prognostic factors (KPS < 70 or weight loss > 5%), and they were equally distributed between the two groups. The median survival times for the radiation-alone and the combined-modality groups were 11.7 months and 18.1 months, respectively (p = 0.001). The 2-year rates of local control in the radiation-alone and combined-modality groups were 35.4% and 43.1%, respectively (p = 0.1). Grade 3 or worse nonhematologic toxicity occurred in 20% of the patients receiving radiation alone and in 16% of those receiving chemotherapy and radiation. Overall, there were only 4 cases of Grade 3 or worse esophagitis.

CONCLUSION

Despite more Stage IIIB patients in the combined-modality group, the addition of chemotherapy to 3D-CRT produced a survival advantage over 3D-CRT alone in Stage III NSCLC without a concomitant increase in toxicity. Chemotherapy thus appears to be beneficial, even in patients who are receiving higher doses of radiation therapy than are typically given with conventional techniques. Because locoregional failure remains a major challenge in patients with advanced disease, 3D-CRT in conjunction with chemotherapy may allow safe treatment to the dose levels required to further enhance local control.

Role of the sequence of the rne-dependent site in 3' processing of M1 RNA, the catalytic component of Escherichia coli RNase P

The 3' processing of M1 RNA, the catalytic component of Escherichia coli RNase P, occurs by two pathways involving multiple steps. The precursor of M1 RNA has an rne-dependent site downstream of the processing site, whose sequence variation affects the processing efficiency. In this study, we showed that the sequence itself of the rne-dependent site possessed the ability to determine the processing pathways and that it also affected the cleavage specificity with the generation of the processing products at one nucleotide upstream or downstream of the normal cleavage sites.

A small-scale survey on the status of intestinal parasite infections in rural villages in Nepal

The status of intestinal parasite infections was investigated in two rural villages (Chitrasar, Jerona) in Chitwan District, Nepal in 1999. Stool examination was performed with a total of 300 specimens from schoolchildren by formalin-ether sedimentation technique. The prevalence rate of intestinal parasite infections in the surveyed areas was 44.0%. The prevalence rate in Jerona was slightly higher than that in Chitrasar. The prevalence rate of intestinal parasite infections in female was slightly higher than that in male without statistically significant difference. Entamoeba coli was the most commonly found protozoan parasite (21.0%) followed by Giardia lamblia (13.7%) and others (5.3%). Hookworm was the most prevalent intestinal helminth (13.0%) followed by Trichuris trichiura (3.0%) and others (5.0%). Forty-three specimens (14.3%) showed mixed infections. It is necessary to implement large-scale treatment with anthelminthics, health education and sanitary improvement for intestinal parasite control in the surveyed areas.

Contact endoscopy of the larynx: a quantitative study

Contact endoscopy is a technique of obtaining detailed magnified images of living epithelium, using a modified glass rod lens endoscope placed on the surface of the tissue. The technique has been extensively described in gynaecological, and more recently, laryngeal and nasal tissues. However, no quantitative studies of its diagnostic accuracy yet exist. A prospective partially blinded controlled study of eight cases with a variety of laryngeal pathologies is described. A single pathologist with no knowledge of the ultimate histological diagnoses successfully identified six of eight laryngeal pathologies on contact endoscopic findings, while the other two cases were identified to a degree of accuracy that was sufficient to positively identify the need for standard tissue biopsy. The advantages and disadvantages of the technique are described, along with suggestions for its role in clinical practice.

Variations in the low levels of cyclin D1/BCL1 have prognostic value in chronic lymphocytic leukemia

Cyclin D1 (CyD1)/BCL1 (PRAD1) is expressed at high levels in almost all cases of mantle cell leukemia/lymphoma (MCL) and in rare cases of chronic lymphocytic leukemia (CLL). The CyD1/BCL1 protein plays an important role in the progression of cells through the G1 phase of cell cycle. Most of the CyD1/BCL1 protein expression studies are performed using immunohistochemistry. We used a sensitive solid-phase radioimmunoassay (RIA) to quantify CyD1 protein expression in 199 patients with CLL. Of these 137 patients were previously untreated with the rest having had standard chemotherapeutic regimens including alkylating agents and fludarabine before being referred to our center. Median white cell count in these patients was 49x10(3) /microl (range 3.0-438.5x10(3)/microl), hemoglobin level 13.1 g/dl (range 5.2-17.3 g/dl), platelet count 157x10(3) /microl (range 10-377x10(3) /microl), age 58 (range 26-89), and beta2-microglobulin 2.75 mg/dl (range 1.1-14.3). The median radioactivity (CPM) of mononuclear cells obtained from 56 normal individuals was assigned a value of 1. There was no significant variation in CyD1 levels among normal individuals (SD=0. 12). While most CyD1 levels in MCL varied from 6.5 to 15.6, the median CyD1/BCL1 in CLL was 1.4 with 75th percentile under 2.12. Rare CLL cases (3.5%) showed levels between 4 and 8.83. When divided into two groups at the median level, patients with higher CyD1/BCL1 expression had shorter survival (P = 0.03). This remained true when applied only to the previously untreated patients (P=0.05). Despite the relatively low expression, the CyD1/BCL1 levels in univariate analysis were as good or better predictors of survival than Binet (P = 0.03) or Rai (P = 0.05) staging. Furthermore, CyD1/BCL1 levels correlated with serum beta2-microglobulin (P = 0.001), white blood cell count (P = 0.004) and hemoglobin levels at the time of collection (P = 0.0003) but not with lymphocyte count, platelet count or age. The data demonstrate that CyD1/BCL1 is likely to play a significant role in the biology of CLL and can be used as a prognostic indicator. Further studies to clarify the role of CyD1 in the biology of CLL and its value as a prognostic indicator at the time of diagnosis are encouraged.

In vitro analysis of processing at the 3'-end of precursors of M1 RNA, the catalytic subunit of Escherichia coli RNase P: multiple pathways and steps for the processing

M1 RNA of 377 nucleotides, the catalytic subunit of Escherichia coli RNase P, is produced by a 3' processing reaction from precursor M1 RNA, a major transcript from the rnpB gene. We analyzed products and intermediates generated by the in vitro processing reaction using a 40% ammonium sulfate precipitate of the S30 fraction (ASP-40) and determined their involvement in the processing. From the results we proposed a model of two pathways for 3' processing of M1 RNA. In this model, one pathway (pathway I) involves +385/+386 intermediates and the other pathway (pathway II) does not. The position of the 3'-end of the precursor molecule determined the choice of the pathways. The precursor having the 3'-end of +413 was processed by both pathways while that having the +415 end was processed only by pathway II. The ASP-40 fraction generated processing products (termed +378/+379 RNA) containing one or two more nucleotides at the 3'-end than M1 RNA, regardless of which pathway was used. Therefore, both pathways require the final 3' trimming for complete processing. The endonucleolytic generation of +378/+379 RNA by pathway II was blocked by the rne-3071 mutation, suggesting that this step is carried out by RNase E.

Expression of C5 protein, the protein component of Escherichia coli RNase P, from the tac promoter

The accurate function of C5 protein, the protein component of Escherichia coli RNase P, is uncertain in vivo. A controllable expression system for C5 protein was constructed which can be used to investigate effects of C5 protein on various cellular functions including biosynthesis of RNase P in vivo. The semisynthetic rnpA gene encoding C5 protein was fused to the tac promoter of the pKK223-3 expression vector. This tac promoter expression system produced a high level of C5 protein upon induction with isopropyl-beta-D-thiogalacto-pyranoside. When the overexpressed C5 protein was purified and used for reconstitution of RNase P, the reconstituted enzyme was active. The N-terminal amino acid of the overexpressed C5 protein was leucine specified by the second codon of the rnpA gene. The more controllable expression system was constructed by introducing the lacIq gene into the vector sequence itself.

First Report of Grapevine Kober Stem Grooving in the United States

The last decade has brought extensive new plantings of grapevines (Vitis vinifera L.) to California vineyards. In some vineyards, severe viruslike problems have been observed (2). To ascertain possible causal agent(s), extensive testing for grapevine viruses was initiated. Testing included a 2-year woody index on indicators V. rupestris cv. Saint George, LN 33, V. vinifera cv. Cabernet Franc, and Kober 5BB. To our knowledge, this is the first field survey for grape virus diseases in the United States that includes woody indexing on Kober 5BB, a relatively new indicator for the grapevine rugose wood diseases (1). A Sonoma County field selection of Sauvignon Blanc grafted to the rootstock Freedom was included in these tests; the 2-year-old vines exhibited stunting, leaf rolling, leaf yellowing, wood necrosis, and pitting symptoms at the graft union. When indexed on the four indicators, the following disease symptoms were observed: stem pitting on V. rupestris; corky bark on LN 33; leafroll on Cabernet Franc; and stem grooving on Kober 5BB. An enzyme-linked immunosorbent assay confirmed the presence of grapevine leafroll-associated viruses 2, and 3, as well as Grapevine Virus A, which is associated with Kober stem grooving. The Sauvignon Blanc selection appears to be infected with several grapevine viruses, as is often the case when virus symptoms in vineyards are severe. Among these disease agents, only Kober stem grooving is reported to cause the severe pitting and grooving symptoms observed on the indicator Kober 5BB (1). This is the first report of Kober stem grooving in the United States. References: (1) R. Garau et al. Vitis 33:161, 1994. (2) D. A. Golino. Am. J. Enol. Vitic. 44:148, 1993.

A Role for Cytokinins in De-Etiolation in Arabidopsis (det Mutants Have an Altered Response to Cytokinins)

When grown in the absence of light, Arabidopsis thaliana deetiolated (det) mutants develop many of the characteristics of light-grown plants, including the development of leaves and chloroplasts, the inhibition of hypocotyl growth elongation, and elevated expression levels of light-regulated genes. We show here that dark-grown wild-type seedlings exhibit similar phenotypic traits if any one of a variety of cytokinins are present in the growth medium. We further show that the striking phenotype of det mutants is unlikely to be caused by different levels of cytokinins in these mutants. The three major Arabidopsis cytokinins, zeatin, zeatin riboside, and isopentenyladenosine, accumulate to similar levels in wild-type seedlings grown in either the light or the dark. There is no consistently different pattern for the levels of these cytokinins in wild-type versus det1 or det2 mutants. However, det1 and det2 have an altered response to cytokinin in a detached leaf senescence assay and in tissue culture experiments. A model is proposed in which light and cytokinins act independently or sequentially through common signal transduction intermediates such as DET1 and DET2 to control the downstream light-regulated responses.