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1.
ISME Commun ; 4(1): ycad002, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38304082

RESUMEN

Dry permafrost is a challenging environment for microbial life due to cold, dry, and often oligotrophic conditions. In 2016, Elephant Head, Antarctica, was confirmed as the second site on Earth to contain dry permafrost. It is geographically distinct from the McMurdo Dry Valleys where dry permafrost has been studied previously. Here, we present the first study of the microbial activity, diversity, and functional potential of Elephant Head dry permafrost. Microbial activity was measured using radiorespiration assays with radiolabeled acetate as a carbon source at 5, 0, and -5°C. Low, but detectable, rates of microbial activity were measured in some samples at 0 and -5°C. This is distinct from previous studies of McMurdo Dry Valley dry permafrost which concluded that dry permafrost represents a cold-arid limit to life on the planet. The isolation of cold-adapted organisms from these soils, including one capable of subzero growth, further supports that the Elephant Head dry active layer and dry permafrost harbor viable microbial life, which may be active in situ. Metagenomic, 16S rRNA gene, and internal transcribed spacer and amplicon sequencing identified similar microbial communities to other Antarctic and cold environments. The Elephant Head microbial community appears to be adapted for survival in cold, dry, and oligotrophic conditions based on the presence of cold adaptation and stress response genes in the metagenomes. Together, our results show that dry permafrost environments do not exclude active microbial life at subzero temperatures, suggesting that the cold, dry soils of Mars may also not be as inhospitable as previously thought.

2.
Nature ; 625(7996): 679-684, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38267683

RESUMEN

In conventional Bardeen-Cooper-Schrieffer superconductors1, electrons with opposite momenta bind into Cooper pairs due to an attractive interaction mediated by phonons in the material. Although superconductivity naturally emerges at thermal equilibrium, it can also emerge out of equilibrium when the system parameters are abruptly changed2-8. The resulting out-of-equilibrium phases are predicted to occur in real materials and ultracold fermionic atoms, but not all have yet been directly observed. Here we realize an alternative way to generate the proposed dynamical phases using cavity quantum electrodynamics (QED). Our system encodes the presence or absence of a Cooper pair in a long-lived electronic transition in 88Sr atoms coupled to an optical cavity and represents interactions between electrons as photon-mediated interactions through the cavity9,10. To fully explore the phase diagram, we manipulate the ratio between the single-particle dispersion and the interactions after a quench and perform real-time tracking of the subsequent dynamics of the superconducting order parameter using nondestructive measurements. We observe regimes in which the order parameter decays to zero (phase I)3,4, assumes a non-equilibrium steady-state value (phase II)2,3 or exhibits persistent oscillations (phase III)2,3. This opens up exciting prospects for quantum simulation, including the potential to engineer unconventional superconductors and to probe beyond mean-field effects like the spectral form factor11,12, and for increasing the coherence time for quantum sensing.

3.
Eur J Ophthalmol ; 34(2): 589-593, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-37956464

RESUMEN

PURPOSE: To present a case and surgical technique for management of Pseudomonas aeruginosa panophthalmitis secondary to an infected scleral buckle. METHODS: Surgical technique video for management of an infected scleral buckle resulting in panophthalmitis with scleral buckle and suture explant and insertion of a subpalpebral lavage system. RESULTS: After two months, the visual acuity was restored to hand motion, likely secondary to a fibrotic secondary membrane, and the retina remain attached. This reports the first description of globe salvage for panophthalmitis from a P. aeruginosa-infected scleral buckle. CONCLUSION: This case encourages surgeons to remove all aspects of an exposed scleral buckle, including sutures, and emphasizes the importance of routine culture of all explanted material, even in the absence of clinical infection. In addition, this case encourages the use of a subpalpebral lavage in cases of severe P. aeruginosa ocular infections.


Asunto(s)
Panoftalmitis , Desprendimiento de Retina , Humanos , Pseudomonas aeruginosa , Panoftalmitis/cirugía , Terapia Recuperativa , Irrigación Terapéutica , Curvatura de la Esclerótica , Desprendimiento de Retina/cirugía
4.
Case Rep Ophthalmol Med ; 2023: 3288984, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37273837

RESUMEN

Purpose. We report a case of bacterial keratitis secondary to an undescribed Bergeyella sp. Bergeyella spp. are not easily cultured, and many reports have identified unculturable isolates through broad-range bacterial polymerase chain reaction (PCR). Observations. A healthy 29-year-old male was attempting to repair an acrylic cannabis water pipe when it shattered and a fragment hit him in the left eye. Two weeks later, he presented with foreign body sensation, scleral injection, and photophobia that were refractory to prolonged corticosteroid therapy. Following a subconjunctival triamcinolone injection, the patient developed a hypopyon and multifocal, midstromal, epithelized corneal infiltrates. Broad-range PCR of the aqueous fluid detected deoxyribonucleic acid closely matching the Bergeyella genus. Empiric treatment directed toward gram-negative bacteria led to the clinical resolution of the inflammation. Conclusions and Importance. This is the first reported case of ocular inflammation secondary to a Bergeyella spp.. As broad-range PCR testing becomes more accessible, we anticipate that additional PCR-positive and culture-negative scenarios will occur.

6.
Phys Rev Lett ; 130(11): 113202, 2023 Mar 17.
Artículo en Inglés | MEDLINE | ID: mdl-37001062

RESUMEN

We propose to simulate bosonic pair creation using large arrays of long-lived dipoles with multilevel internal structure coupled to an undriven optical cavity. Entanglement between the atoms, generated by the exchange of virtual photons through a common cavity mode, grows exponentially fast and is described by two-mode squeezing of effective bosonic quadratures. The mapping between an effective bosonic model and the natural spin description of the dipoles allows us to realize the analog of optical homodyne measurements via straightforward global rotations and population measurements of the electronic states, and we propose to exploit this for quantum-enhanced sensing of an optical phase (common and differential between two ensembles). We discuss a specific implementation based on Sr atoms and show that our sensing protocol is robust to sources of decoherence intrinsic to cavity platforms. Our proposal can open unique opportunities for next-generation optical atomic clocks.

8.
Diagnostics (Basel) ; 12(7)2022 Jul 14.
Artículo en Inglés | MEDLINE | ID: mdl-35885616

RESUMEN

We report a case of a 74-year-old gentleman who presented with floaters and decreased vision in the right eye after cataract surgery. His past medical history was significant for metastatic renal cell carcinoma (mRCC) to bone, lung and abdomen which was presumed stable for the last two years while on the tyrosine kinase inhibitor (TKI), pazopanib. Clinical examination revealed significant vitritis with a distinctive clumping of cells on the pre-retinal surface and posterior hyaloid face. Magnetic resonance imaging of the brain revealed new lesions suspicious for metastases. A diagnostic vitrectomy was performed to determine the nature of the vitritis and clear the visual axis. Cytopathologic evaluation of the vitreous demonstrated clusters of malignant cells that were positive for AE1/AE3 and PAX-8, and negative for the CD20, CD3, RCC, SOX-10 and S-100 immunohistochemical markers. The overall findings favored a metastatic RCC to the vitreous. Choroidal and retinal metastases from mRCC have been previously reported; however, vitreous involvement by mRCC with no evidence of retinal or choroidal mass has not been described. New treatments of mRCC include TKIs which target vascular endothelial growth factor receptors (VEGFRs). Herein, we analyze the factors that could have precipitated this unusual metastasis to the vitreous.

9.
Am J Ophthalmol Case Rep ; 27: 101593, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-35664450

RESUMEN

Purpose: Birdshot Retinochoroiditis (BRC) is an uncommon but distinct form of bilateral posterior uveitis. It is generally of indolent onset, making early natural history difficult to study. Our report seeks to expand knowledge on the natural history of the onset of BRC. Observations: Our patient presented with clinical features that were consistent with unilateral BRC, despite it being defined as a bilateral condition. Over the course of one year he developed retinal vasculitis, vitritis and fundus features of BRC in the second eye. Conclusions and Importance: Although BRC is a bilateral disease, our case demonstrates that the onset may sometimes be sequential instead of simultaneous. Unilateral disease that is characteristic of BRC should be monitored for second-eye involvement with multi-modal imaging including fundus photography, angiography, perimetry, electroretinography, and optical coherence tomography of the macula with emphasis on the choroidal thickness.

10.
J Acad Ophthalmol (2017) ; 14(2): e166-e168, 2022 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-37388174

RESUMEN

Purpose The aim of this study was to evaluate the ophthalmology residency match results to determine changes in the rate of home-institution matches during the coronavirus disease 2019 (COVID-19) pandemic. Methods Aggregate deidentified summary match result data from 2017 to 2022 was obtained from the Association of University Professors of Ophthalmology and the San Francisco (SF) Match. A chi-squared test was performed to determine if the rate of candidate matching to the home residency program in ophthalmology was higher in the post-COVID-19 compared with pre-COVID-19 match years. A literature review using PubMed was performed of other medical subspecialty match rates to home institution during the same study period. Results A chi-squared test for difference in proportions confirmed a significantly higher chance of matching to the home program for ophthalmology in the post-COVID-19, SF Match year of 2021 to 2022 compared with 2017 to 2020 ( p = 0.001). Other medical specialties including otolaryngology, plastic surgery, and dermatology also showed similar increased home institution residency match rates during the same time period. Although neurosurgery and urology also had increased trend rates for home institution match rates, these results did not reach statistical significance. Conclusions The ophthalmology home-institution residency SF Match rate was significantly increased during the COVID-19 pandemic year 2021 to 22. This mirrors a trend reported in other specialties including the otolaryngology, dermatology, and plastic surgery in the 2021 match. Additional study will be required to identify factors leading to this observation.

11.
Science ; 373(6555): 673-678, 2021 08 06.
Artículo en Inglés | MEDLINE | ID: mdl-34353950

RESUMEN

Fully controllable ultracold atomic systems are creating opportunities for quantum sensing, yet demonstrating a quantum advantage in useful applications by harnessing entanglement remains a challenging task. Here, we realize a many-body quantum-enhanced sensor to detect displacements and electric fields using a crystal of ~150 trapped ions. The center-of-mass vibrational mode of the crystal serves as a high-Q mechanical oscillator, and the collective electronic spin serves as the measurement device. By entangling the oscillator and collective spin and controlling the coherent dynamics via a many-body echo, a displacement is mapped into a spin rotation while avoiding quantum back-action and thermal noise. We achieve a sensitivity to displacements of 8.8 ± 0.4 decibels below the standard quantum limit and a sensitivity for measuring electric fields of 240 ± 10 nanovolts per meter in 1 second. Feasible improvements should enable the use of trapped ions in searches for dark matter.

12.
Phys Rev Lett ; 126(17): 173601, 2021 Apr 30.
Artículo en Inglés | MEDLINE | ID: mdl-33988424

RESUMEN

We propose to simulate dynamical phases of a BCS superconductor using an ensemble of cold atoms trapped in an optical cavity. Effective Cooper pairs are encoded via the internal states of the atoms, and attractive interactions are realized via the exchange of virtual photons between atoms coupled to a common cavity mode. Control of the interaction strength combined with a tunable dispersion relation of the effective Cooper pairs allows exploration of the full dynamical phase diagram of the BCS model as a function of system parameters and the prepared initial state. Our proposal paves the way for the study of the nonequilibrium features of quantum magnetism and superconductivity by harnessing atom-light interactions in cold atomic gases.

13.
Cornea ; 40(3): 377-379, 2021 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-32991358

RESUMEN

PURPOSE: To report a patient who presented with red eye and diffuse palpebral conjunctival thickening and papillary growth bilaterally. METHODS: A 63-year-old woman with a medical history of stage IV adenocarcinoma of the lung with metastasis to the bone, the lung, and the lymph nodes presented with redness and irritation of both eyes for 3 months. The patient has been treated with topical corticosteroids for 3 weeks with no relief of symptoms. RESULTS: Clinical examination and pathology report of conjunctival biopsy confirmed the diagnosis of conjunctival acanthosis nigricans. CONCLUSIONS: Conjunctival acanthosis nigricans is a rare paraneoplastic condition that resembles papilloma and can present a challenge in diagnosis. When acanthosis nigricans occurs after the diagnosis of malignancy, it can be an indicator of progression of the underlying condition. The diagnosis of conjunctival acanthosis nigricans in a patient with no history of cancer should prompt clinicians for further malignancy workup.


Asunto(s)
Acantosis Nigricans/diagnóstico , Adenocarcinoma/secundario , Neoplasias Óseas/secundario , Neoplasias de la Conjuntiva/diagnóstico , Neoplasias Pulmonares/patología , Metástasis Linfática , Síndromes Paraneoplásicos Oculares/diagnóstico , Acantosis Nigricans/tratamiento farmacológico , Neoplasias de la Conjuntiva/tratamiento farmacológico , Femenino , Glucocorticoides/uso terapéutico , Humanos , Persona de Mediana Edad , Síndromes Paraneoplásicos Oculares/tratamiento farmacológico
14.
Sci Rep ; 10(1): 17008, 2020 10 12.
Artículo en Inglés | MEDLINE | ID: mdl-33046729

RESUMEN

To compare the effectiveness of self- retained cryopreserved AM as an adjuvant therapy for infectious corneal ulcers. Retrospective, case-control study of 24 eyes of 24 consecutive patients with central and paracentral corneal infectious ulcers and initial visual acuity worse than 20/200. Among them, 11 eyes of 11 patients received additional placement of self-retained cryopreserved AM. Epithelialization and Best Corrected Snellen Visual Acuity (BCSVA) were compared between the two groups. At baseline, both groups had comparable age, gender, visual acuity (VA), size and location of corneal ulcer. Patients receiving additional placement of cryopreserved AM had significantly faster epithelialization within 3.56 ± 1.78 weeks vs 5.87 ± 2.20 weeks (p = 0.01) and achieved complete epithelialization in significantly more patients (72.7% vs 23.1% p = 0.04) despite overall larger baseline defect size (32.7 ± 19.5 mm2 vs 21.5 ± 10.7 mm2, p = 0.11). Consequently, the AM group had clinically significant BCSVA (> 3 lines) (81.8% vs 38.4%, p = 0.047) and total VA improvement (log MAR 0.7 ± 0.6 vs 1.6 ± 0.9, p = 0.016) compared to the control group at the time of complete epithelialization. In-office sutureless AM may be an effective adjuvant therapy in treating sight-threatening infectious corneal ulcers by promoting faster corneal epithelialization and overall better recovery of the VA.


Asunto(s)
Amnios/trasplante , Úlcera de la Córnea/cirugía , Epitelio Corneal/cirugía , Repitelización/fisiología , Adulto , Anciano , Estudios de Casos y Controles , Epitelio Corneal/fisiopatología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Resultado del Tratamiento , Adulto Joven
15.
Am J Ophthalmol Case Rep ; 19: 100761, 2020 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-32529120

RESUMEN

PURPOSE: To report successful management of acute ocular graft-versus-host disease (oGVHD) by self-retained cryopreserved amniotic membrane (AM). OBSERVATIONS: A 69-year-old male developed acute oGVHD following hematopoietic stem cell transplantation (HSCT) with severe dryness, pain, photophobia, and blurred vision, the right eye worse than the left eye. Despite topical artificial tears, corticosteroids, and bandage contact lens (BCL) for two weeks, his right eye deteriorated with increasing redness and blurred vision and presented with diffuse conjunctival inflammation, severe superficial punctate keratitis, and corneal and limbal epithelial defect. Hence, self-retained cryopreserved AM was applied in the right eye while conventional therapy was continued in the left eye. Placement of self-retained AM for 3-days resulted in resolution of symptoms, reduction in inflammation, and complete re-epithelialization of the corneal and limbal defect with the visual acuity improving from 20/500 to 20/70 in the right eye. In contrast, the visual acuity improved from 20/300 to 20/150 and remained inflamed with conventional therapy in the left eye. One-month post-AM placement, the right eye remained asymptomatic with the visual acuity improved to 20/30 without any additional therapy, whereas the left eye improved to 20/70 with conventional treatment of BCL, loteprednol, and artificial tears. CONCLUSIONS AND IMPORTANCE: This case suggests application of self-retained AM can be an effective treatment to accelerate the restoration of vision and corneal surface health for acute oGVHD.

16.
Nature ; 580(7805): 602-607, 2020 04.
Artículo en Inglés | MEDLINE | ID: mdl-32350478

RESUMEN

Interactions between atoms and light in optical cavities provide a means of investigating collective (many-body) quantum physics in controlled environments. Such ensembles of atoms in cavities have been proposed for studying collective quantum spin models, where the atomic internal levels mimic a spin degree of freedom and interact through long-range interactions tunable by changing the cavity parameters1-4. Non-classical steady-state phases arising from the interplay between atom-light interactions and dissipation of light from the cavity have previously been investigated5-11. These systems also offer the opportunity to study dynamical phases of matter that are precluded from existence at equilibrium but can be stabilized by driving a system out of equilibrium12-16, as demonstrated by recent experiments17-22. These phases can also display universal behaviours akin to standard equilibrium phase transitions8,23,24. Here, we use an ensemble of about a million strontium-88 atoms in an optical cavity to simulate a collective Lipkin-Meshkov-Glick model25,26, an iconic model in quantum magnetism, and report the observation of distinct dynamical phases of matter in this system. Our system allows us to probe the dependence of dynamical phase transitions on system size, initial state and other parameters. These observations can be linked to similar dynamical phases in related systems, including the Josephson effect in superfluid helium27, or coupled atomic28 and solid-state polariton29 condensates. The system itself offers potential for generation of metrologically useful entangled states in optical transitions, which could permit quantum enhancement in state-of-the-art atomic clocks30,31.

17.
Phys Rev Lett ; 124(19): 193602, 2020 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-32469538

RESUMEN

In the context of quantum metrology, optical cavity-QED platforms have primarily been focused on the generation of entangled atomic spin states useful for next-generation frequency and time standards. Here, we report a complementary application: the use of optical cavities to generate nonclassical states of light for electric field sensing below the standard quantum limit. We show that cooperative atom-light interactions in the strong collective coupling regime can be used to engineer generalized atom-light cat states which enable quantum enhanced sensing of small displacements of the cavity field even in the presence of photon loss. We demonstrate that metrological gains of 10-20 dB below the standard quantum limit are within reach for current cavity-QED systems operating with long-lived alkaline-earth atoms.

18.
Case Rep Ophthalmol Med ; 2020: 6760272, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32148986

RESUMEN

PURPOSE: To report an unusual presentation of commercial cannabidiol (CBD) oil-induced Stevens-Johnson Syndrome/toxic epidermal necrolysis (SJS-TEN). METHODS: A 56-year-old woman presented with acute onset of a diffuse, blistering, maculopapular rash with over 30% total body surface area (BSA) involvement two days after taking CBD oil sublingually for chronic pain. Biopsy confirmed SJS-TEN. Ophthalmology was consulted and mild eye involvement was found. She was started on topical cyclosporine, prednisone, moxifloxacin, and erythromycin ointment to prevent progression, which was successful. She was otherwise treated with supportive therapy in the intensive care burn unit and ultimately passed away from septic shock. CONCLUSION: In this case, we described an unusual drug-induced SJS from a commercial, non-FDA-regulated cannabis product. The use of a commercial CBD product should be cautioned due to potential for series of drug reactions to the cannabis product and the risk for reaction to other unregulated other pharmacological components.

19.
Ocul Immunol Inflamm ; 28(2): 217-227, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-30821569

RESUMEN

Purpose: To investigate the link between treatment with CTLA-4 and PD-1 checkpoint blockade inhibitors and the development of noninfectious uveitis.Methods: A survey was distributed to uveitis specialists to identify patients who developed uveitis while receiving either PD-1 inhibitors pembrolizumab and nivolumab; PD-L1 inhibitors atezolizumab, avelumab, and durvalumab; or the CTLA-4 inhibitor ipilimumab.Results: Fifteen patients from seven institutions were identified. The most common cancer diagnosis (13/15) was malignant melanoma. Fourteen patients had a new uveitis diagnosis following checkpoint blockade administration (six anterior uveitis, six panuveitis, one posterior uveitis, one anterior/intermediate combined); one patient developed optic neuritis. Uveitis was diagnosed within 6 months after drug initiation for 11/12 patients (median 63 days). Corticosteroid treatment was effective for most patients, although two patients had permanent loss of vision.Conclusions: Patients on checkpoint inhibitor therapy should be educated to seek care if they develop ocular symptoms, and prompt referral to specialists should be incorporated into oncology protocols.


Asunto(s)
Antineoplásicos Inmunológicos/uso terapéutico , Antígeno CTLA-4/antagonistas & inhibidores , Receptor de Muerte Celular Programada 1/antagonistas & inhibidores , Uveítis/tratamiento farmacológico , Humanos , Uveítis/inmunología , Uveítis/metabolismo
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