Biomarkers and sepsis severity as predictors of mechanical ventilation and mortality in COVID-19.

Introduction: Patients with septic shock face an elevated risk of mortality compared to those with sepsis. Several biomarkers, including lactate dehydrogenase, albumin, and lactate/albumin (L/A), have been associated with increased mortality in COVID-19 patients. This study aims to assess the relationship between sepsis, septic shock, and mortality, as well as the need for mechanical ventilation in COVID-19 patients. Demographic, sepsis severity factors, and biomarkers are examined. Methods: A retrospective case series from June 2020 to March 2021 included 490 patients diagnosed with sepsis or septic shock secondary to SARS-CoV-2 pneumonia. Time-to-event analyses were conducted for mechanical ventilation and mortality. Statistical significance was set at p ≤ .0038. Serum lactate, albumin, lactate/albumin ratio, C-reactive protein, platelet levels, and three sepsis severity scales, (CCI, SOFA, APACHE IV) were assessed. Results: Sepsis was identified in 352 patients (71.8%), while 138 had septic shock. Patients with septic shock were more likely to require invasive ventilator support. Factors associated with a higher risk of intubation included higher APACHE IV scores, elevated serum albumin levels, and increased L/A ratio. L/A ratio and serum lactate levels demonstrated the best diagnostic accuracy for mechanical ventilation (AUC, 0.964 and 0.946, respectively), mortality (AUC, 0.926 and 0.887, respectively). Discussion: Increased C-reactive protein, combined with increased serum lactate and a high lactate/albumin ratio, may assist clinicians in identifying COVID-19 patients at risk of mechanical ventilation and mortality upon admission. Optimal cut-off values for lactate (1.45-1.65 mmol/L) and L/A ratio (0.413) can aid in prioritizing medical care for at risk COVID-19 patients.

Tomographic findings and mortality in patients with severe and critical pneumonia with COVID-19 diagnosis.

Introduction: A high percentage of patients with non-severe (17.9%) and severe (2.9%) atypical pneumonia do not display pulmonary tomographic findings upon hospital admission; furthermore, lesion associated with COVI-19 are peripherally distributed in a multifocal ground-glass pattern, as well as displaying an irregular consolidation pattern, with a posterior or lower lobe predilection. The main objective of this study was to identify the pulmonary radiological patterns in patients diagnosed with SARS-CoV-2 pneumonia, the factors associated with the need for mechanical ventilation, as well as their survival rates at 30 days. Methods: We report the pulmonary tomographic findings of 490 consecutive patients with severe and critical pneumonia due to SARS-CoV-2. The patients were classified according to the tomography and demographic findings, sepsis severity prognostic scales, Charlson comorbidity index (CCI), the Sequential Organ Failure Assessment (SOFA), and the Acute Physiology and Chronic Health Evaluation (APACHE IV). The Kaplan-Meier method was used to calculate survival distributions. Results: 89.80% of patients had ground-glass opacities, 81.63% radiologic consolidation sign, 42.45% vascular thickening pattern, 37.55% lymphadenopathies, 14.90% pleural effusion, and 2.65% pulmonary thrombosis; meanwhile, 91.02% had bilateral lesions, 85.51% had peripheral lesions, and 75.92% had basal lobe lesions. APACHE IV (HR, 1.191, 95% CI [1.126, 1.260]), SOFA (HR, 5.178, 95%CI [3.103, 8.641]), and CCI (HR, 0.673, 95%CI [0.510, 0.889]), as well as the pulmonary damage severity index (HR, 1.282, 95%CI [1.151, 1.428]), predict the need for invasive mechanical ventilation. Only moderate ARDS patients with mild and severe lung disease showed different 30-day mortality distributions (χ2 = 7.00, p = 0.008). Discussion: Although the survival distributions did not vary significantly, an overwhelming majority of patients (i.e., 84.35%) with a higher pulmonary damage severity index (i.e., 23>) died within 30 days of hospital admission, while only 25.91% with moderate lung damage and 2.42% with mild lung damage.

Pulmonary thromboembolism and alveolar hemorrhage as initial manifestations of systemic lupus erythematosus.

Systemic lupus erythematosus (SLE) is an autoimmune disease that affects multiple organs. SLE can affect the lung, the pulmonary vasculature, and the pleura. A 38-year-old female with limb pain and ecchymosis who later developed pulmonary thromboembolism and alveolar hemorrhage is presented here. Clinical, imaging, laboratory, and histopathological evidence is presented. The patient met the European League Against Rheumatism (EULAR) and the American College of Rheumatology (ACR) criteria for SLE. Furthermore, the patient had a Systemic Lupus Erythematosus Disease Activity Index 2000 (SLEDAI-2K) score of 35; thus, indicating severe disease. This case is an example of concomitant venous and arterial lung complications in an SLE patient.

Suspended LRSPP for the development of highly integrated active plasmonic devices.

We present a novel long-range surface plasmon polariton (LRSPP) device consisting of a suspended dielectric matrix in which an electrically active, millimeter-long metallic waveguide is embedded. We show that, by opening an air gap under the lower cladding, the influence of the substrate is suppressed and the symmetry of the thermo-optical distribution around the LRSPP waveguide is preserved over extended ranges of applied electrical current with minimal optical losses. Experimental results show that, compared to a standard nonsuspended structure, our device allows either the induction of a phase change that is three times larger, for a fixed electrical power, or, equivalently, a scaling down of the device to one-tenth of its original length, for a fixed phase change.

Few-mode erbium-doped fiber amplifier with photonic lantern for pump spatial mode control.

We demonstrate a few-mode erbium-doped fiber amplifier employing a mode-selective photonic lantern for controlling the modal content of the pump light. Amplification of six spatial modes in a 5 m long erbium-doped fiber to ∼6.2 dBm average power is obtained while maintaining high modal fidelity. Through mode-selective forward pumping of the two degenerate LP21 modes operating at 976 nm, differential modal gains of <1 dB between all modes and signal gains of ∼16 dB at 1550 nm are achieved. In addition, low differential modal gain for near-full C-band operation is demonstrated.

Sphingosine-1-phosphate, regulated by FSH and VEGF, stimulates granulosa cell proliferation.

Sphingosine-1-phosphate (S1P) is a bioactive polar sphingolipid which stimulates proliferation, growth and survival in various cell types. In the ovary S1P has been shown protect the granulosa cells and oocytes from insults such as oxidative stress and radiotherapy, and S1P concentrations are greater in healthy than atretic large follicles. Hence, we postulate that S1P is fundamental in follicle development and that it is activated in ovarian granulosa cells in response to FSH and VEGF. To test this hypothesis we set out: i) to evaluate the effect of FSH and VEGF on S1P synthesis in cultured bovine granulosa cells and ii) to analyse the effect of S1P on proliferation and survival of bovine granulosa cells in vitro. Seventy five thousand bovine granulosa cells from healthy medium-sized (4-7mm) follicles were cultured in 96-well plates in McCoy's 5a medium containing 10ng/mL of insulin and 1ng/mL of LR-IGF-I at 37°C in a 5% CO2/air atmosphere at 37°C. Granulosa cell production of S1P was tested in response to treatment with FSH (0, 0.1, 1 and 10ng/mL) and VEGF (0, 0.01, 0.1, 1, 10 and 100ng/mL) and measured by HPLC. Granulosa cells produced S1P at 48 and 96h, with the maximum production observed with 1ng/mL of FSH. Likewise, 0.01ng/mL of VEGF stimulated S1P production at 48, but not 96h of culture. Further, the granulosa cell expression of sphingosine kinase-1 (SK1), responsible for S1P synthesis, was demonstrated by Western blot after 48h of culture. FSH increased the expression of phosphorylated SK1 (P<0.05) and the addition of a SK1 inhibitor reduced the constitutive and FSH-stimulated S1P synthesis (P<0.05). Sphingosine-1-phosphate had a biphasic effect on granulosa cell number after culture. At low concentration S1P (0.1µM) increased granulosa cell number after 48h of culture (P<0.05) and the proportion of cells in the G2 and M phase of the cell cycle (P<0.05), whereas higher concentrations decreased cell number (10µM; P<0.05) by an increase (P<0.05) in the proportion of cells in apoptosis (hypodiploid cells). In addition, treatment with SK-178 suppressed the FSH- and VEGF-stimulated rise of the granulosa cells number (P<0.05). Interestingly, the effect of 0.1µM S1P on granulosa cell number and their proportion in G2/M phases is similar to that observed with 1ng/mL FSH. The results of this study are the first to demonstrate sphingosine-1-phosphate (S1P) synthesis in granulosa cells under the control of FSH and VEGF. The later achieved through the regulation of sphingosine kinase 1 expression. This S1P augments the proportion of cells in the G2/M phase of the cell cycle that translates in increased granulosa cell proliferation.

Six mode selective fiber optic spatial multiplexer.

Low-loss all-fiber photonic lantern (PL) mode multiplexers (MUXs) capable of selectively exciting the first six fiber modes of a multimode fiber (LP01, LP11a, LP11b, LP21a, LP21b, and LP02) are demonstrated. Fabrication of the spatial mode multiplexers was successfully achieved employing a combination of either six step or six graded index fibers of four different core sizes. Insertion losses of 0.2-0.3 dB and mode purities above 9 dB are achieved. Moreover, it is demonstrated that the use of graded index fibers in a PL eases the length requirements of the adiabatic tapered transition and could enable scaling to large numbers.

P450-aromatase mRNA is expressed in the corpus luteum (CL) of the non-pregnant sheep and goat: the expression of the enzyme is present throughout pregnancy in the goat CL.

In most mammals, the corpus luteum (CL) and placenta are the major sources of progesterone. The goat pregnancy depends on the presence of CL after mid-gestation, while sheep pregnancy does not. The expression and distribution of P450-aromatase (P450-Aro) mRNA throughout gestation has not been investigated in the goat CL and partially in the sheep CL. The present research was designed to characterize the expression of P450-Aro mRNA in small ruminant CL with emphasis in the goat. For this purpose, ovaries from Criollo goats and Pelibuey sheeps were analysed using in situ reverse transcription-polymerase chain reaction (RT-PCR) for the histological detection of P450-Aro transcripts. In addition, P450-Aro expression was determined by in vitro RT-PCR. In situ RT-PCR studies showed that the goat and sheep CL were rich in cells positive for P450-Aro mRNA. We have also found in vitro RT-PCR expression of P450-Aro mRNA in goat CL at 1, 3 and 4 months of gestation. This study shows that the goat CL expresses P450-Aro mRNA along gestation, suggesting that this structure is capable to produce oestrogens up to the end of gestation.

Fiber-optic sensor for liquid level measurement.

A novel (to the best of our knowledge) liquid level sensor based on multimode interference (MMI) effects is proposed and demonstrated. By using a multimode fiber (MMF) without cladding, known as no-core fiber, liquids around the MMF modify the self-imaging properties of the MMI device and the liquid level can be detected. We show that the sensor exhibits a highly linear response with the sensing range and multiplexed operations easily controlled by just modifying the length of the no-core fiber. At the same time, we can measure the refractive index of the liquid based on the maximum peak wavelength shift. We can also use the sensor for continuous and discrete liquid level sensing applications, thus providing a liquid level sensor that is inexpensive with a very simple fabrication process.

Expression of P450-aromatase in the goat placenta throughout pregnancy.

The enzyme P450-aromatase (P450-Aro) is essential for the conversion of androgens to estrogens. The objective was to study the expression and distribution of P450-Aro in goat placentae throughout pregnancy. For this purpose, we used reverse transcription-polymerase chain reaction (RT-PCR) with primers derived from the ovarian cDNA sequence found by our group. The expression of P450-Aro mRNA was first detected by in vitro RT-PCR in cotyledons at 4 months and was still present at term. Based on in situ RT-PCR, cotyledon microvilli expressed P450-Aro mRNA early in pregnancy; the signal was detected in the syncytiotrophoblast and in non-fused cytotrophoblasts inside the microvilli, but was scarce in the interstitial cells of the villous core. In the last 2 months of pregnancy (including at term), the expression of P450-Aro mRNA was still detected in the syncytiotrophoblast. However, P450-Aro was never detected in the caruncule (regardless of stage of pregnancy). In conclusion, P450-Aro was expressed in the goat placenta microvilli starting early in pregnancy; the expression and distribution of the enzyme increased throughout pregnancy and was still present at term.

Ultra-widely tunable long-period holey-fiber grating by the use of mechanical pressure.

We report an ultra-widely tunable long-period holey-fiber grating, which combines the wide-range single-mode behavior and transverse strain sensitivity of the holey fibers with the advantages of mechanically induced long-period fiber gratings. We obtain a versatile widely tunable long-period holey-fiber grating with attractive transmission spectral characteristics for optical communications, fiber-based amplifiers, and lasers. The mechanically induced long-period holey-fiber grating shows a continuous tuning range over 500 nm, more than 12 dB depth notches with less than 0.75 dB out-of-band losses, and bandwidth control from 10 to 40 nm.

Citric acid demineralization and subepithelial connective tissue grafts.

BACKGROUND: The present study was designed to evaluate the effect, if any, of citric acid root demineralization in the outcome of subepithelial connective tissue grafts performed to cover localized gingival recessions. METHODS: Thirty-six patients participated, each providing one gingival recession; 19 received citric acid demineralization, while 17 did not. All were treated surgically with subepithelial connective tissue grafts and followed for 6 months. At baseline and 6 months, the following parameters were recorded: plaque index, gingival index, recession height, probing depth, recession width, and amount of keratinized tissue. Data were analyzed statistically to 1) evaluate the results achieved with each procedure individually over time and 2) compare the results obtained with the 2 procedures after 6 months. RESULTS: Results showed significant reductions in recession height after 6 months independently of whether citric acid was applied or not (2.79+/-0.79 versus 2.56+/-0.73). Similarly, recession width was significantly reduced (3.74+/-1.19 versus 3.50 +/-0.73), and the width of keratinized tissue was significantly increased (2.47+/-1.6 versus 2.3+/-1.2). No significant changes in probing depth were found (-0.16+/-0.06 versus -0.13+/-0.81). No significant differences were found when both techniques were compared in any one of the parameters analyzed (all P >0.30). CONCLUSIONS: It is concluded that: 1) the subepithelial connective tissue graft procedure provides a satisfactory solution in the treatment of localized gingival recessions, and 2) citric acid demineralization does not affect the clinical outcome of the surgical technique.

Vector soliton fiber lasers.

We show by simulations that a nonlinear optical loop mirror with birefringent fiber can have intensity-dependent transmission of vector soliton pulses with a 50/50 coupler. Using this result we propose two mode-locked laser cavity designs.

Beam amplification resulting from non-Bragg wave mixing in photorefractive strontium barium niobate.

Two-wave mixing with a small angle between beams in a photorefractive crystal biased with an external electric field leads to the formation of additional non-Bragg orders and to wave amplification. A steady-state gain of 25 cm (-1) was obtained for an external voltage of 3 kV/cm in strontium barium niobate. Noise amplification and oscillation are also demonstrated.

Observation of interaction forces between one-dimensional spatial solitons in photorefractive crystals.

We propagate two coherent and parallel beams of a He-Ne laser through a Bi(12)TiO(20) photorefractive crystal in the presence of drift nonlinearity. Our experimental results demonstrate that the beams attract or repel each other according to their initial phase difference. They attract each other when they are initially in phase and they repel each other when they are initially out of phase. These experimental results agree with numerical predictions recently published.

Modulation Z-scan technique for characterization of photorefractive crystals.

We propose a simple single-beam configuration for characterization of the amplitude, speed of growth, and polarization properties of the photoinduced refractive-index change that is due to a drift photorefractive mechanism of nonlinearity in crystals, namely, the modulation Z-scan technique, based on the modulation of an externally applied electric field. The results of a simple theoretical model developed for one-dimensional parabolic photorefractive lens formation in this configuration are illustrated by original experiments with a semi-insulating GaAs crystal at lambda -1.06 microm.

Formation of steady-state cylindrical thermal lenses in dark stripes.

Characteristic features of the formation of cylindrical laser-induced thermal steady-state lenses in the dark stripes associated with spatial dark-soliton propagation are analyzed and verified experimentally in an ethanol-dye solution. Positive focusing power perpendicular to the dark stripe is ensured by defocusing along the axis of this stripe and depends strongly on the shape of the light-beam profile and the orientation of the dark stripe within it.

Experimental evidence of modulation instability in a photorefractive Bi(12)TiO(20) crystal.

We present experimental results on the propagation of an interference pattern of two He-Ne laser beams of unequal amplitudes through a photorefractive Bi(12)TiO(20) crystal in the presence of drift nonlinearity. The phenomenon that we have observed is the focusing of the fringes as the nonlinearity of the crystal is increased. We show that such a phenomenon can be quantitatively interpreted in the framework of modulation instability theory.

Anticoagulant and estrogenic effects of two new 17 beta-aminoestrogens, butolame [17 beta-(4-hydroxy-1-butylamino)-1,3,5(10)-estratrien-3-ol] and pentolame [17 beta-(5-hydroxy-1-pentylamino)-1,3,5(10)-estratrien-3-ol].

The syntheses and characterizations of two new 17 beta-aminoestrogens, butolame [17 beta-(4-hydroxy-1-butylamino)-1,3,5(10)-estratrien-3-ol] and pentolame [17 beta-(5-hydroxy-1-pentylamino)-1,3,5(10)-estratrien-3-ol], are presented. Both compounds, when administered in single subcutaneous injections to male mice and rats, produce dose-dependent increases in blood clotting times that may last several days. The estrogenic effects assessed by the vaginal cornification test are of relatively short duration.