Systemic Mastocytosis - a Diagnostic Challenge

Mastocytosis refers to a group of disorders characterized by the infiltration of clonally derived mast cells to the skin or extracutaneous tissues resulting in a heterogeneous clinical picture. It is a rare hematologic disorder in all its forms. The exact incidence is unknown; it affects patients of any age and males and females equally. Its molecular pathogenesis is incompletely understood. The clinical features of mastocytosis result from both chronic and episodic mast cell mediator release, signs and symptoms arising from diffuse or focal tissue infiltration, and, occasionally, the presence of an associated non-mast cell clonal hematologic disease. The histopathologic analysis is essential for definitive diagnosis but there is no curative treatment. The authors report a clinical case of a 72-year-old woman with no history of allergies, with bicytopenia, weight loss, and diffuse axial osteolytic lesions. This is a rare clinical case of aggressive systemic mastocytosis for which palliative treatment can improve survival and quality of life. A brief review of the literature about this pathology is also included

Primary gas thermometry by means of laser-absorption spectroscopy: Determination of the Boltzmann constant

We report on a new optical implementation of primary gas thermometry based on laser absorption spectrometry in the near infrared. The method consists in retrieving the Doppler broadening from highly accurate observations of the line shape of the R(12) $\nu_{1} + 2 \nu_{2}^{\phantom{1}0} + \nu_{3}$ transition in CO$_{2}$ gas at thermodynamic equilibrium. Doppler width measurements as a function of gas temperature, ranging between the triple point of water and the gallium melting point, allowed for a spectroscopic determination of the Boltzmann constant with a relative accuracy of $\sim1.6\times10^{-4}$.Comment: Submitted to Physical Review Letter

High Neutrophil-to-Lymphocyte and Platelet-to-Lymphocyte Ratios Are Associated with a Higher Risk of Hemodialysis Vascular Access Failure

Our aim was to determine the predictive role of the preoperative neutrophil-to-lymphocyte ratio (NLR) and platelet-to-lymphocyte ratio (PLR) in vascular access malfunctioning in patients who had undergone their first native arterio-venous fistula (AVF) for hemodialysis. Methods: This was a single-center retrospective observational study. All patients who underwent the procedure of the creation of a first native AVF for hemodialysis from January 2019 to December 2020 were considered eligible to be part of this study. Reinterventions for AVF malfunctioning were registered and the population was subdivided into two groups with respect to AVF malfunctioning. ROC curves were obtained to find the appropriate cut-off values for the NLR and PLR. A multivariate analysis was used to identify the independent predictors for an AVF malfunction. Kaplan–Meier curves were used to evaluate the AVF patency rates. A total of 178 patients were enrolled in the study, of them 70% (n = 121) were male. The mean age was 67.5 ± 12 years. Reinterventions for AVF malfunctioning were performed on 102 patients (57.3%). An NLR > 4.21 and a PLR > 208.8 was selected as the cut-off for AVF malfunctioning. The study population was divided into two groups depending on the NLR and PLR values of the individual. For the NLR < 4.21 group, the AVF patency rates were 90.7%, 85.3%, and 84% at the 3-, 6-, and 12-month follow-up, respectively, and 77.5%, 65.8%, and 39.3% at 3, 6, and 12 months for the NLR > 4.21 group, respectively (p < 0.0001). For the PLR < 208.8 group, the patency rates were 85.6%, 76.7%, and 67.7% at the 3-, 6-, and 12-month follow-up. For the PLR > 208.28 group, the patency rates were 80.8%, 71.2%, and 50.7% for the 3-, 6-, and 12-month follow-up, respectively (p = 0.014). The multivariate analysis highlighted that diabetes mellitus, the neutrophil count, the lymphocyte count, and the NLR were independent risk factors for an AVF failure. In our experience, the NLR and PLR are useful markers for the stratification of vascular access failure in hemodialysis patients. The inexpensive nature and ready availability of the values of these biomarkers are two points of strength for everyday clinical practice

Versatile OSCAT time-domain THz spectrometer

: We report on a compact and versatile time-domain spectrometer operating in the THz spectral region from 0.2 to 2.5 THz based on ultrafast Yb:CALGO laser and photo-conductive antennas. The spectrometer operates with the optical sampling by cavity tuning (OSCAT) method based on laser repetition rate tuning, which allows at the same time the implementation of a delay-time modulation scheme. The whole characterization of the instrument is presented and compared to the classical THz time-domain spectroscopy implementation. THz spectroscopic measurements on a 520-μm thick GaAs wafer substrate together with water vapor absorption measurements are also reported to further validate the instrument capabilities

Passive mode locking of a Tm,Ho:KY(WO4)(2) laser around 2 μm

We report the first demonstration, to our knowledge, of passive mode locking in a Tm3+, Ho3+-codoped KYWO42 laser operating in the 2000-2060 nm spectral region. An InGaAsSb-based quantum well semiconductor saturable absorber mirror is used for the initiation and stabilization of the ultrashort pulse generation. Pulses as short as 3.3 ps were generated at 2057 nm with average output powers up to 315 mW at a pulse repetition frequency of 132 MHz for 1.15 W of absorbed pump power at 802 nm from a Ti:sapphire laser

Comb-assisted spectroscopy of CO2 absorption profiles in the near- and mid-infrared regions

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Cavitation phenomenon in mechanical prosthetic valves: Not only microbubbles

Introduction: Microbubbles (MBs) or cavitation is high-velocity, echo-bright findings present during the closing or opening of a mechanical valve (MVP). Cavitation bubble growth or gas emboli are less frequently described. We evaluated the hemodynamic parameters involved in the formation of gas emboli and the impact of gas emboli on requests for additional investigations. Methods and Results: Transthoracic echocardiographic studies (TTE) of 57 patients (31 males, mean age 46.8\ua0\ub1\ua013.8\ua0years) with gas emboli were evaluated after heart valve replacement surgery. The majority (72%, n\ua0=\ua042) had a mitral or combined mitral/aortic MVP, with 28% (n\ua0=\ua016) an aortic MVP. The last TTE with and without gas emboli were considered for the same patient and the no emboli group was the control group (42 patients). The patient's blood pressure (BP) and heart rate (HR) were available for each TTE. Comparing the two TTEs, the systolic and diastolic BP, transmitral and aortic gradients, and left ventricular ejection fraction were similar but the HR (80.9\ua0\ub1\ua018.7 vs 72.5\ua0\ub1\ua013.9\ua0bpm, P\ua0=.02) was significantly higher in the group with gas emboli. A TEE was performed 52 times in 27 patients, due to gas emboli, with one case positive for thrombus/vegetation. For 19 patients, a brain CT was requested. In two patients, the indication for the brain CT was gas emboli but the result was negative. Conclusion: Gas emboli are frequently present and associated to an increased HR. They can cause the misdiagnosis of endocarditis or thrombus formation with significant additional requests for diagnostic examinations

Performance and costs of a rapid syphilis test in an urban population at high risk for sexually transmitted infections

Introduction. Rapid syphilis screening could facilitate caseidentification in populations at high risk for sexually transmitted infections (STI). The aim of this study was to compare the performance and the cost-effectiveness of a rapid immunochromatography syphilis test with a traditional ELISA screening test in patients with suspected infectious syphilis or patients at high risk for STI/syphilis. Methods. Consecutive patients attending a STI clinic cosensually underwent serological testing with two different tests. Sensitivity, specificity, Positive Predictive Values, Negative Predictive Values and effectiveness of the two tests were evaluated with respect to definitive diagnosis. Results. In our population, the immunochromatography essay (Abbott Determine Syphilis TP) had a sensitivity of 95.0% (95% CI 88.7-97.8) and a specificity of 97.7% (95% CI 94.7-99.0). The ELISA test had a sensitivity of 95.0% (95% CI 88.8-97.9) and a specificity of 97.2% (95% CI 94.1-98.7). The Positive Predictive Value for ELISA was 94.1% (95% CI 87.6-97.3) and 95.0% (95% CI 88.7-97.8) for the rapid test. The Negative Predictive Value was 97.7% (95% CI 94.7-99) for both ELISA and the rapid tests. The cost-effectiveness analysis showed that the rapid test was less expensive than ELISA (? 26.46 vs ? 40.57) and yielded a similar number of right diagnoses. Conclusions. The Abbott Determine Syphilis TP test is an accurate, easy and inexpensive test that could facilitate the rapid detection of syphilis in high-risk urban patients