Structural basis of calmodulin modulation of the rod cyclic nucleotide-gated channel.

Calmodulin (CaM) regulates many ion channels to control calcium entry into cells, and mutations that alter this interaction are linked to fatal diseases. The structural basis of CaM regulation remains largely unexplored. In retinal photoreceptors, CaM binds to the CNGB subunit of cyclic nucleotide-gated (CNG) channels and, thereby, adjusts the channel's Cyclic guanosine monophosphate (cGMP) sensitivity in response to changes in ambient light conditions.

The structure of cyclic nucleotide-gated channels in rod and cone photoreceptors.

Cyclic nucleotide-gated (CNG) channels play a central role in rod and cone photoreceptors of the vertebrate retina. In photoreceptors, light triggers a series of biochemical reactions that ultimately close CNG channels and evoke a brief voltage pulse, a signal that is later passed on to the brain. Malfunction of CNG channels can lead to loss of vision.

Structural basis of the partially open central gate in the human CNGA1/CNGB1 channel explained by additional density for calmodulin in cryo-EM map.

The recently reported structure of the human CNGA1/CNGB1 CNG channel in the open state (Xue et al., 2021a) shows that one CNGA1 and one CNGB1 subunit do not open the central hydrophobic gate completely upon cGMP binding. This is different from what has been reported for CNGA homomeric channels (Xue et al.

The structure of the native CNGA1/CNGB1 CNG channel from bovine retinal rods.

In rod photoreceptors of the retina, the cyclic nucleotide-gated (CNG) channel is composed of three CNGA and one CNGB subunits, and it closes in response to light activation to generate an electrical signal that is conveyed to the brain. Here we report the cryo-EM structure of the closed state of the native rod CNG channel isolated from bovine retina. The structure reveals differences between CNGA1 and CNGB1 subunits.

Reducing the Carbon Footprint of Academic Conferences: The Example of the American Society of Tropical Medicine and Hygiene.

We calculated carbon emissions associated with air travel of 4,834 participants at the 2019 annual conference of the American Society of Tropical Medicine and Hygiene (ASTMH). Together, participants traveled a total of 27.7 million miles or 44.

Estimating, monitoring and minimizing the travel footprint associated with the development of the Athena X-ray Integral Field Unit: An on-line travel footprint calculator released to the science community.

Global warming imposes us to reflect on the way we carry research, embarking on the obligation to minimize the environmental impact of our research programs, with the reduction of our travel footprint being one of the easiest actions to implement, thanks to the advance of digital technology. The X-ray Integral Field Unit (X-IFU), the cryogenic spectrometer of the Athena space X-ray observatory of the European Space Agency will be developed by a large international consortium, currently involving 240 members, split over 13 countries, 11 in Europe, Japan and the United States. The travel footprint associated with the development of the X-IFU is to be minimized.

Supernovae. ⁴⁴Ti gamma-ray emission lines from SN1987A reveal an asymmetric explosion.

In core-collapse supernovae, titanium-44 ((44)Ti) is produced in the innermost ejecta, in the layer of material directly on top of the newly formed compact object. As such, it provides a direct probe of the supernova engine. Observations of supernova 1987A (SN1987A) have resolved the 67.

An ultraluminous X-ray source powered by an accreting neutron star.

The majority of ultraluminous X-ray sources are point sources that are spatially offset from the nuclei of nearby galaxies and whose X-ray luminosities exceed the theoretical maximum for spherical infall (the Eddington limit) onto stellar-mass black holes. Their X-ray luminosities in the 0.5-10 kiloelectronvolt energy band range from 10(39) to 10(41) ergs per second.

Asymmetries in core-collapse supernovae from maps of radioactive 44Ti in Cassiopeia A.

Asymmetry is required by most numerical simulations of stellar core-collapse explosions, but the form it takes differs significantly among models. The spatial distribution of radioactive (44)Ti, synthesized in an exploding star near the boundary between material falling back onto the collapsing core and that ejected into the surrounding medium, directly probes the explosion asymmetries. Cassiopeia A is a young, nearby, core-collapse remnant from which (44)Ti emission has previously been detected but not imaged.

Radio detections during two state transitions of the intermediate-mass black hole HLX-1.

Relativistic jets are streams of plasma moving at appreciable fractions of the speed of light. They have been observed from stellar-mass black holes (~3 to 20 solar masses, M(⊙)) as well as supermassive black holes (~10(6) to 10(9) M(⊙)) found in the centers of most galaxies. Jets should also be produced by intermediate-mass black holes (~10(2) to 10(5) M(⊙)), although evidence for this third class of black hole has, until recently, been weak.

An intermediate-mass black hole of over 500 solar masses in the galaxy ESO 243-49.

Ultraluminous X-ray sources are extragalactic objects located outside the nucleus of the host galaxy with bolometric luminosities exceeding 10(39) erg s(-1). These extreme luminosities-if the emission is isotropic and below the theoretical (Eddington) limit, where the radiation pressure is balanced by the gravitational pressure-imply the presence of an accreting black hole with a mass of approximately 10(2)-10(5) solar masses (M[symbol: see text]). The existence of such intermediate-mass black holes is in dispute, and though many candidates have been proposed, none are widely accepted as definitive.

Cat-scratch disease simulating a malignant process of the chest wall.

Unlabelled: Cat-scratch disease is a well-known cause of regional adenopathy in immunocompetent children. Rarely, patients may present with symptoms simulating a neoplastic disease. The case of a 12-year-old boy with fever, swelling of the chest wall and hepatosplenic nodules is reported.

[Bacteroides fragilis meningitis revealing a meningorectal fistula].

Unlabelled: Cases of meningitis due to Bacteroides fragilis are rare; we report a case revealing a meningorectal fistula.

Case Report: A 2-month-old infant developed a severe sepsis syndrome following a rectosigmoidoscopy for rectal bleeding. Lumbar puncture diagnosed bacterial meningitis.

Changes in the expression of the heme-regulated eIF-2 alpha kinase and heat shock proteins in rabbit reticulocytes maturing during recovery from anemia.

Changes in the expression of the heme-regulated eIF-2 alpha kinase (HRI), heat shock proteins (Hsps, Hsp90, and 70) and their associated cohorts (p60 and p23) were studied in maturing rabbit reticulocytes during recovery from anemia. Reticulocytosis was induced by injection of N-acetylphenylhydrazine or by phlebotomy from the ear vein, and circulating red blood cells were fractionated on histopaque density gradients. Northern and Western blot analyses indicated that HRI and hsps mRNA and protein content gradually decreased during maturation of reticulocytes into erythrocytes.

[Post-natal diagnostic strategy of urinary tract malformations detected by prenatal screening].

Background: The increasing experience with prenatal ultrasonographic diagnosis allows detection of more and more mild urinary tract anomalies. Thus, the clinical significance of many pyelectasis detected before birth is not known.

Patients And Methods: From a retrospective study of 78 patients, we determined the positive predictive value (PPV) of prenatal ultrasound findings for urinary tract malformations.

Torsion of the gallbladder in children.

Two cases of torsion of the gallbladder in children (ages 5 and 7) are reported, and the relevant literature is reviewed. The condition is extremely rare in the pediatric population, and the correct diagnosis is rarely made preoperatively. However, the clinical presentation may be evocative of the diagnosis.

[Adamantinoma of the tibia. X-ray computed tomographic and MRI study. Apropos of a case].

Adamantinoma of the long bones in a very rare tumor that mainly affects the tibia. Its diagnosis is difficult both radiologically, as the lesion appears as a poorly specific metaphyseal lacuna with or without periosteal reaction, and histologically. Its prognosis used to be guarded because of recurrence and of possible metastatic diffusion, but it has been considerably improved by wide resection with reconstruction.

[X-ray computed tomographic study of the ethmoid bone and middle meatus. III. Application to chronic infectious sinus pathology].

As nasal endoscopy, high resolution CT is a part of the chronic rhinosinusitis pre-operative assessment. It shows, thanks to a precise and anatomical study of the ethmoid and sinusal draining, the extension of the diseases and the local morphological variations which predispose to chronic diseases. The main aspects of chronic sinusitis, nasal polyposis and fungal maxillary sinus diseases are reported.

[Intrathoracic chondrosarcoma arising at a rib in a patient with multiple exostoses].

A case of chondrosarcoma arising from the 7th left rib in a patient with multiple exostosis disease is reported. The initial CT scan feature is a purely intrathoracic mass with a parietal and pericardial junction and calcifications within the tumor. A review of the literature about the costal chondrosarcoma and their CT scan features is done and shows the uncommon initial aspect of this case.

[Pelvic cystic lymphangioma. Apropos of a case in an adult].

The authors report about the observation of a subperitoneal pelvic cystic lymphangioma in an adult patient: ultrasound and CT dat had yet never been described for the rare pelvic form, and are the same as with the other locations of cystic lymphangioma in adults.

[Epithelioid hemangioendothelioma of the liver and superior vena cava. Radiological results apropos of a case in an adult].

Epithelioid hemangioendothelioma is a rare, ubiquitous, vascular tumor, difficult to diagnosis but sometimes identified after detection of metastases, and with a prognosis intermediary between angioma and angiosarcoma. The tumors have been described as developing in the large venous trunks and recently lesions have been reported in liver. Little documented data exist with respect to radiologic appearances.

[Aneurysm of an aberrant right subclavian artery. Original contribution of x-ray computed tomography and digital subtraction angiography].

An original aspect of a case of atheromatous aneurysm of an aberrant right subclavian artery was the evaluation of the complementary diagnostic value of CT scan and intravenous digital subtraction angiography imaging. The vascular anomaly was clearly identified, the CT scan visualizing the aneurysm sac more effectively and the angiography providing a vascular cartography. These two non-invasive exploratory examinations provide complementary data for the preoperative diagnosis and investigation of the aberrant right subclavian artery aneurysm.