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1.
Proc Natl Acad Sci U S A ; 120(9): e2210037120, 2023 02 28.
Artículo en Inglés | MEDLINE | ID: mdl-36812197

RESUMEN

Despite its massive potential, Raman imaging represents just a modest fraction of all research and clinical microscopy to date. This is due to the ultralow Raman scattering cross-sections of most biomolecules that impose low-light or photon-sparse conditions. Bioimaging under such conditions is suboptimal, as it either results in ultralow frame rates or requires increased levels of irradiance. Here, we overcome this tradeoff by introducing Raman imaging that operates at both video rates and 1,000-fold lower irradiance than state-of-the-art methods. To accomplish this, we deployed a judicially designed Airy light-sheet microscope to efficiently image large specimen regions. Further, we implemented subphoton per pixel image acquisition and reconstruction to confront issues arising from photon sparsity at just millisecond integrations. We demonstrate the versatility of our approach by imaging a variety of samples, including the three-dimensional (3D) metabolic activity of single microbial cells and the underlying cell-to-cell variability. To image such small-scale targets, we again harnessed photon sparsity to increase magnification without a field-of-view penalty, thus, overcoming another key limitation in modern light-sheet microscopy.


Asunto(s)
Iluminación , Microscopía , Microscopía/métodos , Fotones , Imagenología Tridimensional/métodos
2.
Eur Phys J E Soft Matter ; 46(12): 118, 2023 Dec 05.
Artículo en Inglés | MEDLINE | ID: mdl-38051443

RESUMEN

We report here the spontaneous formation of lipid-bilayer-wrapped virus particles, following the injection of "naked" virus particles into the subphase of a Langmuir trough with a liquid monolayer of lipids at its air-water interface. The virus particles are those of the well-studied cowpea chlorotic mottle virus, CCMV, which are negatively charged at the pH 6 of the subphase; the lipids are a 9:1 mix of neutral DMPC and cationic CTAB molecules. Before adding CCMV particles to the subphase we establish the mixed lipid monolayer in its liquid-expanded state at a fixed pressure (17.5 mN/m) and average area-per-molecule of (41Å2). Keeping the total area fixed, the surface pressure is observed to decrease at about 15 h after adding the virus particles in the subphase; by 37 h it has dropped to zero, corresponding to essentially all the lipid molecules having been removed from the air-water interface. By collecting particles from the subphase and measuring their sizes by atomic force microscopy, we show that the virus particles have been wrapped by lipid bilayers (or by two lipid bilayers). These results can be understood in terms of thermal fluctuations and electrostatic interactions driving the wrapping of the anionic virus particles by the cationic lipids. Spontaneous acquisition by a virus particle of, first, a hydrophobic lipid monolayer envelope and, then, a hydrophilic lipid bilayer envelope, as it interacts from the subphase with an oppositely charged Langmuir monolayer.


Asunto(s)
Membrana Dobles de Lípidos , Fosfolípidos , Membrana Dobles de Lípidos/química , Fosfolípidos/química , Agua/química , Propiedades de Superficie
3.
Ecotoxicol Environ Saf ; 188: 109893, 2020 Jan 30.
Artículo en Inglés | MEDLINE | ID: mdl-31735370

RESUMEN

Cellular and humoral responses were evaluated in Litopenaeus vannamei juveniles when exposed to malathion, endosulfan, and their mixture. Each experiment was performed in the hemolymph collected at each exposure time (5 and 96 h) in duplicate; total hemocyte count, coagulation time, hemocyanin concentration, phenoloxidase (PO) and superoxide dismutase (SOD) activities were quantified. Survival was not affected by pesticides applied individually and mixed. Clotting time did not show significant differences concerning increase of concentration percentage of the pesticides tested. In organisms exposed to the pesticide mixture, hemocyanin decreased at 5 h of exposure as the concentration increased. Only in the malathion experiment did exposed shrimp to 10 and 50% of the LC50-96 h show significantly (p < 0.05) higher hemocyte contents. For malathion, significantly (p < 0.05) lower PO values in shrimp exposed to higher concentrations (10 and 50% of the LC50-96 h) were determined. While for the mixture treatment, high SOD value was determined at high exposure time and concentration. Malathion was the pesticide that showed an effect on some variables even at sublethal concentrations. The Continuous Concentration Criteria of the United States Environmental Protection Agency did not represent effects on the variables when they were compared with the averages of the control group.


Asunto(s)
Endosulfano/toxicidad , Inmunidad Celular/efectos de los fármacos , Inmunidad Humoral/efectos de los fármacos , Malatión/toxicidad , Penaeidae/efectos de los fármacos , Animales , Sinergismo Farmacológico , Hemocianinas/sangre , Hemocitos/efectos de los fármacos , Hemocitos/inmunología , Hemolinfa/efectos de los fármacos , Hemolinfa/inmunología , Monofenol Monooxigenasa/metabolismo , Penaeidae/inmunología
4.
Opt Lett ; 42(5): 1011-1014, 2017 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-28248354

RESUMEN

Through simulations and experiment, this Letter shows how a particle's extinction cross section can be extracted from a digital hologram. Spherical and nonspherical particles are considered covering a range of cross-sectional values of nearly five orders of magnitude. The extracted cross sections are typically less than 10% in error from the true values. It is also shown that holograms encompassing a sufficiently large angular range of scattered light yield an estimate for the absorption cross section.

5.
Clin Exp Hypertens ; 39(6): 513-519, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28678544

RESUMEN

Hypertension (HBP) is a chronic disease characterized by increased blood pressure, which despite several treatments maintains a high morbi-mortality, which suggests that there are other mechanisms involved in this pathology, within which the orphan receptors could be candidates for the treatment of the HBP; these receptors are called orphan receptors because their ligand is unknown. These receptors have been suggested to participate in some pathologies because they are associated with various systems such as GPR88, which has been linked to the dopaminergic system, and GPR124 with angiogenesis, suggesting that these receptors could take part in HBP. Hence, the aim of this work was to study the expression of orphan receptors GPR88 and GPR124 in various tissues of normotensive and hypertensive rats. We used Wistar Kyoto (WKY) and spontaneously hypertensive rat (SHR) of 6-8 and 10-12 weeks of age and we determined systolic blood pressure (SBP), heart rate, as well as mRNA of GPR88 and GPR124 receptors by reverse transcription polymerase chain reaction (RT-PCR) in the aorta, heart, kidney, and brain. Our results showed that GPR88 and GPR124 were expressed in all analyzed tissues, but their expression is dependent on the age and development of HBP because their expression tends to be modified as HBP is established. Therefore, we conclude that GPR88 and GPR124 receptors may be involved in the development or maintenance of high blood pressure.


Asunto(s)
Expresión Génica , Hipertensión/genética , ARN Mensajero/metabolismo , Receptores Acoplados a Proteínas G/genética , Animales , Aorta/metabolismo , Presión Sanguínea , Encéfalo/metabolismo , Frecuencia Cardíaca , Riñón/metabolismo , Masculino , Miocardio/metabolismo , Ratas , Ratas Endogámicas SHR , Ratas Endogámicas WKY
6.
Clin Exp Hypertens ; 38(1): 56-62, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-26268856

RESUMEN

Diabetes and hypertension have been associated with cardiovascular diseases and stroke. Some reports have related the coexistence of hypertension and diabetes with increase in the risk of developing vascular complications. Recently some studies have shown results suggesting that in the early stages of diabetes and hypertension exist a reduced functional response to vasopressor agents like angiotensin II (Ang II), which plays an important role in blood pressure regulation mechanism through the activation of its AT1 and AT2 receptors. For that reason, the aim of this work was to study the gene and protein expression of AT1 and AT2 receptors in aorta of diabetic SHR and WKY rats. Diabetes was induced by the administration of streptozotocin (60 mg/kg i.p.). After 4 weeks of the onset of diabetes, the protein expression was obtained by western blot and the mRNA expression by RT-PCR. Our results showed that the hypertensive rats have a higher mRNA and protein expression of AT1 receptors than normotensive rats while the AT2 expression remained unchanged. On the other hand, the combination of diabetes and hypertension increased the mRNA and protein expression of AT1 and AT2 receptors significantly. In conclusion, our results suggest that diabetes with hypertension modifies the mRNA and protein expression of AT1 and AT2 receptors. However, the overexpression of AT2 could be associated with the reduction in the response to Ang II in the early stage of diabetes.


Asunto(s)
Angiotensina II/metabolismo , Aorta/metabolismo , Diabetes Mellitus Experimental/metabolismo , Hipertensión/metabolismo , Receptor de Angiotensina Tipo 1 , Receptor de Angiotensina Tipo 2 , Animales , Aorta/fisiopatología , Presión Sanguínea/fisiología , Diabetes Mellitus Experimental/complicaciones , Diabetes Mellitus Experimental/fisiopatología , Perfilación de la Expresión Génica , Hipertensión/complicaciones , Hipertensión/fisiopatología , Masculino , ARN Mensajero/metabolismo , Ratas , Ratas Endogámicas SHR , Ratas Endogámicas WKY , Receptor de Angiotensina Tipo 1/genética , Receptor de Angiotensina Tipo 1/metabolismo , Receptor de Angiotensina Tipo 2/genética , Receptor de Angiotensina Tipo 2/metabolismo
7.
Opt Lett ; 39(13): 3993-6, 2014 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-24978790

RESUMEN

This work presents a new concept to measure the extinction cross section for a single particle in situ. The concept involves recording the hologram produced by the interference of a particle's forward-scattered light with the incident light. This interference pattern is fundamentally connected to the energy flow that gives rise to extinction, and, by integrating this measured pattern, one obtains an approximation for the cross section. Mie theory is used to show that this approximation can be as little as 1% in error of the true value for many cases of practical interest. Moreover, since an image of the particle can be computationally reconstructed from a measured hologram using the Fresnel-Kirchhoff diffraction theory, one can obtain the cross section simultaneously with the particle shape and size.

8.
J Relig Health ; 53(5): 1285-96, 2014 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-23572240

RESUMEN

This study examines the association between beliefs about God and psychiatric symptoms in the context of Evolutionary Threat Assessment System Theory, using data from the 2010 Baylor Religion Survey of US Adults (N = 1,426). Three beliefs about God were tested separately in ordinary least squares regression models to predict five classes of psychiatric symptoms: general anxiety, social anxiety, paranoia, obsession, and compulsion. Belief in a punitive God was positively associated with four psychiatric symptoms, while belief in a benevolent God was negatively associated with four psychiatric symptoms, controlling for demographic characteristics, religiousness, and strength of belief in God. Belief in a deistic God and one's overall belief in God were not significantly related to any psychiatric symptoms.


Asunto(s)
Cultura , Trastornos Mentales/psicología , Religión y Psicología , Adulto , Femenino , Humanos , Masculino , Encuestas y Cuestionarios , Estados Unidos
9.
Cureus ; 16(5): e60592, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38894762

RESUMEN

The intricate relationship between cancer and cardiovascular diseases (CVD), notably heart failure (HF), is gaining attention in the medical field. This literature review explores the intricate interplay between cancer and CVD, particularly HF, emphasizing their significant impact on global mortality and comorbidity. While preventive measures have contributed to reducing their incidence, challenges persist in predicting and managing cancer-related complications. This review article delves into various risk factors associated with both cancer and HF, including lifestyle factors, genetic predispositions, and immune system dysregulation. It highlights emerging evidence suggesting a direct interaction between cancer and HF, with studies indicating an elevated risk of mortality from cancer in patients with HF and vice versa. Pathological mechanisms such as inflammation, oxidative stress, and tissue hypoxia are implicated in cancer-induced cardiac dysfunction, underscoring the need for comprehensive clinical investigations and ethical considerations in patient care. The review also discusses the potential role of biomarkers in risk assessment, early detection of cardiotoxicity, and understanding common pathophysiological links between cancer and HF, paving the way for multifaceted preventive and therapeutic approaches.

10.
Cureus ; 16(4): e59392, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38817463

RESUMEN

Immersion pulmonary edema, also known as swimming-induced pulmonary edema (SIPE), manifests with cough, dyspnea, hemoptysis, and hypoxemia from flash pulmonary edema after surface swimming, often in healthy young individuals with no predisposing conditions. SIPE commonly resolves spontaneously within 24-48 hours but can be fatal. Post-mortem findings demonstrate heavy, edematous lungs and frothy airways. Although these pathologic findings are like those seen in patients with drowning, SIPE, by definition, is associated with pulmonary edema that develops with a closed glottis without drowning/aspiration. However, patients who develop SIPE during swimming could lose consciousness and drown. Its pathophysiology is poorly understood, and the medical literature infrequently describes SIPE. Due to the multifactorial and complex pathophysiology and the scarcity of medical literature describing SIPE, the diagnosis could be difficult at presentation. This case report elaborates on diagnosing and treating swimming-induced pulmonary edema in a hypertensive and obese female who presented to our emergency room with an acute onset of shortness of breath after recreational swimming in a pool.

11.
Cureus ; 16(4): e59155, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38803750

RESUMEN

Coronary artery fistulas (CAFs) are rare vascular anomalies characterized by abnormal connections between coronary arteries and cardiac chambers or adjacent structures. Advances in cardiac interventions have led to an increasing recognition of acquired CAFs, which are typically congenital. We present a case of a 62-year-old male with a complex medical history, including hypertension, atrial fibrillation, and heart failure, who presented with exertional chest pain and palpitations. Diagnostic evaluation revealed a significant CAF originating from the right coronary artery (RCA) and terminating into the coronary sinus and right ventricle. Despite the absence of significant coronary artery occlusions, the fistula was deemed clinically significant due to its potential to cause myocardial ischemia. Management involved guideline-directed medical therapy and lifestyle modifications. This case underscores the importance of early recognition and appropriate management of CAFs to optimize patient outcomes. Further research is needed to better understand the natural history and optimal management strategies of CAFs.

12.
Opt Express ; 21(10): 12611-6, 2013 May 20.
Artículo en Inglés | MEDLINE | ID: mdl-23736480

RESUMEN

This work investigates a method for digital holographic imaging of microparticles. Traditional digital holographic techniques use a particle's forward scattered light to form the hologram, whereas here we use the backscattered light. Images of a particle are then computationally reconstructed from the backscatter hologram, and several examples of such reconstructions are presented. A potential advantage of this technique is that the backscatter holograms may be more sensitive to particle-surface details.


Asunto(s)
Holografía/métodos , Interpretación de Imagen Asistida por Computador/métodos , Microesferas , Fotometría/métodos , Refractometría/métodos , Procesamiento de Señales Asistido por Computador
13.
Cureus ; 15(2): e35055, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-36938178

RESUMEN

Brugada syndrome is an aberrant ST-segment elevation in the right precordial leads. It can progress into sudden cardiac death (SCD) among patients with structurally normal hearts. Most patients are asymptomatic at presentation, but those who develop symptoms can present with syncope due to other arrhythmias such as ventricular tachycardia or fibrillation. Early diagnosis and appropriate management can prevent future complications in patients with a significant family history.

14.
Cureus ; 15(1): e34377, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-36874680

RESUMEN

Acute coronary syndrome remains the primary cause of mortality and morbidity in the United States. Cardiac ischemia is a consequence of an imbalance between oxygen demand and supply. The sensitivity of troponin is above 99% in diagnosing cardiac injury; rare exceptions can occur, however. We present a case of acute coronary syndrome with a negative troponin level, even on repeated testing using different methods at two different centers.

15.
Cureus ; 15(11): e49402, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-38149142

RESUMEN

Diabetic ketoacidosis (DKA) is a life-threatening metabolic emergency traditionally associated with Type 1 diabetes but is increasingly recognized in Type 2 diabetes, particularly with the use of sodium-glucose cotransporter-2 (SGLT-2) inhibitors. Euglycemic DKA, characterized by near-normal blood glucose levels, is a distinct variant that has gained attention. This case report highlights a unique presentation of euglycemic DKA in a 56-year-old female with a past medical history of Type 2 Diabetes Mellitus who presented to the emergency department with a one-week history of chest pain.

16.
Spectrochim Acta A Mol Biomol Spectrosc ; 284: 121776, 2023 Jan 05.
Artículo en Inglés | MEDLINE | ID: mdl-36070673

RESUMEN

Ammonia borane, as a source of hydrogen, has attracted much attention due to its high hydrogen content, low molecular weight, and high stability in solution. However, the process and enhancement of hydrogen release must be done practically under ambient conditions. For this work, Raman spectroscopy, principal component analysis (PCA), and molecular simulation were applied to study the hydrogen release process of ammonia borane. Three stages of release were observed from room temperature to 1300 °C. The shift, the appearance, and the disappearance of the Raman bands were evident in the whole process. In-situ monitoring of Raman and PCA, with four different heating rates between 70 and 130 °C, was done; ammonia borane showed visible variations in its first release step, in which a fast rate helped reduce distortion in the release process. Finally, molecular simulation of ammonia borane using the Density Functional Theory (DFT) in calculations showed that dihedral rotation and stretching of the hydrogen bonds can occur before the first release step.


Asunto(s)
Boranos , Amoníaco , Boranos/química , Calefacción , Hidrógeno/química , Espectrometría Raman
17.
Ann Med Surg (Lond) ; 85(7): 3744-3747, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-37427166

RESUMEN

Reverse takotsubo syndrome, a variant of takotsubo cardiomyopathy, is an acute left ventricular failure characterized by the basal akinesis/hypokinesis associated with apical hyperkinesis. Its presentation is similar to that of the acute coronary syndrome. Case presentation: The authors present a case of a 49-year-old woman, a vice principal at a local school with a history of hypertension, who was brought to our center after she collapsed while giving a graduation speech. Reverse takotsubo was a presumed diagnosis after we ruled out other differentials. Clinical discussion: The pathophysiology of reverse takotsubo syndrome is poorly understood. It might be due to a different pattern of catecholamine-mediated myocardial dysfunction than classic takotsubo cardiomyopathy. It is often associated with physical and/or emotional stressors. Conclusion: Supportive treatment and identification and prevention of triggers can reduce the recurrence of reverse takotsubo cardiomyopathy. Physicians should be aware of various triggers for this condition.

18.
Ann Med Surg (Lond) ; 85(7): 3638-3641, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-37427202

RESUMEN

Infective endocarditis (IE) primarily affects the endocardium of heart valves. Neurologic manifestations include strokes, intracerebral hemorrhages, meningitis, cerebral and spinal abscess, and mycotic aneurysms. Although rare, meningitis is a potentially life-threatening complication of IE, so physicians should be aware of this rare and fatal complication of IE. Case presentation: Here, the authors present a case of a 53-year-old male who presented with bacterial meningitis secondary to IE. His blood culture was positive for methicillin-sensitive staphylococcal aureus. Echocardiography findings were suggestive of endocarditis. Despite aggressive intensive care management, our patient did not survive. Clinical discussion: The isolation of Staphylococcus aureus in culture should raise a suspicion of foci being elsewhere outside the central nervous system. Treatment of complications like meningitis may require intrathecal antibiotics. The vegetation and neurological complications are often difficult to treat and require the participation of a multidisciplinary team. Conclusions: The diagnosis of IE in patients presenting with neurologic deficits and fever should be considered. A physician should raise a suspicion of infective foci being elsewhere outside the central nervous system if the organism isolated in culture is Staphylococcus aureus.

19.
J Biophotonics ; 16(9): e202300068, 2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-37287076

RESUMEN

Since its first demonstration over 100 years ago, scattering-based light-sheet microscopy has recently re-emerged as a key modality in label-free tissue imaging and cellular morphometry; however, scattering-based light-sheet imaging with subcellular resolution remains an unmet target. This is because related approaches inevitably superimpose speckle or granular intensity modulation on to the native subcellular features. Here, we addressed this challenge by deploying a time-averaged pseudo-thermalized light-sheet illumination. While this approach increased the lateral dimensions of the illumination sheet, we achieved subcellular resolving power after image deconvolution. We validated this approach by imaging cytosolic carbon depots in yeast and bacteria with increased specificity, no staining, and ultralow irradiance levels. Overall, we expect this scattering-based light-sheet microscopy approach will advance single, live cell imaging by conferring low-irradiance and label-free operation towards eradicating phototoxicity.


Asunto(s)
Microscopía Fluorescente , Microscopía Fluorescente/métodos , Citosol
20.
Cureus ; 15(11): e49191, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-38130546

RESUMEN

This case report explores the intricate diagnostic challenges encountered in a 30-year-old male patient with abdominal pain, jaundice, and a history of acetaminophen use. Initially presenting as a potential case of drug-induced hepatitis due to acetaminophen overdose, the diagnosis took an unexpected turn when the patient tested positive for hepatitis B surface antigen. The case highlights the complexity of diagnosing acute hepatitis, considering multiple potential etiologies, including viral and drug-induced factors. Differential diagnoses for this case involve considering drug-induced hepatitis, autoimmune hepatitis, various viral hepatitis types, and the potential contribution of cocaine-induced hepatitis as individual possibilities or in combination. This case emphasizes the need for a comprehensive evaluation, the consideration of multiple potential causes, and the importance of ongoing monitoring and follow-up to ensure optimal patient care in cases of acute hepatitis.

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