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Human immunodeficiency virus (HIV) infection has historically been related to the development of specific cancers, some of which are so closely linked to the infection, such as Kaposi's Sarcoma (KS), that they have earned the name Acquired Immuno-Deficiency Syndrome (AIDS)-defining cancers (ADCs). While the development of antiretroviral therapy (ART) has decreased the incidence of AIDS-defining cancers, the resulting aging of people living with HIV (PLWH) highlighted an increased occurrence of other forms of cancer. At the "Gaetano Martino" hospital in Messina, we developed a multidisciplinary approach by creating a bridge between the Oncology Unit and the Infectious Diseases Unit to carry out screening and a more rapid diagnostic and therapeutic journey for cancers in PLWH. The goal is to improve the diagnosis of various types of cancer by involving other professionals, such as gastroenterologists and gynecologists, to ensure faster access to treatment and, therefore, a greater chance of survival. In addition, our multidisciplinary approach has also included vaccine screening, offered by the "Gaetano Martino" hospital and useful for preventing the development of specific forms of cancer in the entire population and particularly in PLWH. [ABSTRACT FROM AUTHOR]

Swift J1749.4-2807 is the only known eclipsing accreting millisecond X-ray pulsar. In this paper, we report on seven thermonuclear (Type-I) X-ray bursts observed by NICER during its 2021 outburst. The first six bursts show slow rises and long decays, indicative of mixed H/He fuel, whereas the last burst shows fast rise and decay, suggesting He-rich fuel. Time-resolved spectroscopy of the bursts revealed typical phenomenology (i.e. an increase in blackbody temperature during the burst rise, and steady decrease in the decay), however, they required a variable N H. We found that the values of N H during the bursts were roughly double those found in the fits of the persistent emission prior to each burst. We interpret this change in absorption as evidence of burst–disc interaction, which we observe due to the high inclination of the system. We searched for burst oscillations during each burst and detected a signal in the first burst at the known spin frequency of the neutron star (517.92 Hz). This is the first time burst oscillations have been detected from Swift J1749.4-2807. We further find that each X-ray burst occurs on top of an elevated persistent count rate. We performed time-resolved spectroscopy on the combined data of the bursts with sufficient statistics (i.e. the clearest examples of this phenomenon) and found that the blackbody parameters evolve to hotter temperatures closer to the onset of the bursts. We interpret this as a consequence of an unusual marginally stable burning process similar to that seen through mHz QPOs. [ABSTRACT FROM AUTHOR]

We report the discovery of millihertz quasi-periodic oscillations (mHz QPOs) from the neutron star (NS) low-mass X-ray binary 4U 1730–22 using the Neutron Star Interior Composition Explorer (NICER). After being inactive for almost 50 years, 4U 1730–22 went into outburst twice between June and August 2021, and between February and July 2022. We analyse all the NICER observations of this source, and detect mHz QPOs with a significance > 4 σ in 35 observations. The QPO frequency of the full data set ranged between ∼ 4.5 and ∼ 8.1 mHz with an average fractional rms amplitude of the order of ∼2 per cent. The X-ray colour analysis strongly suggests that 4U 1730–22 was in a soft spectral state during the QPO detections. Our findings are consistent with those reported for other sources where the mHz QPOs have been interpreted as the result of a special mode of He burning on the NS surface called marginally stable nuclear burning (MSNB). We conclude that the mHz QPOs reported in this work are also associated with the MSNB, making 4U 1730–22 the eighth source that shows this phenomenology. We discuss our findings in the context of the heat flux from the NS crust. [ABSTRACT FROM AUTHOR]

The neutron star low-mass X-ray binary SWIFT J1749.4–2807 is the only known eclipsing accreting millisecond X-ray pulsar. In this manuscript, we perform a spectral characterization of the system throughout its 2021, 2-week-long outburst, analysing 11 NICER  observations and quasi-simultaneous XMM-Newton  and NuSTAR  single observations at the outburst peak. The broad-band spectrum is well-modelled with a blackbody component with a temperature of ∼0.6 keV, most likely consistent with a hotspot on the neutron star surface, and a Comptonization spectrum with power-law index Γ ∼ 1.9, arising from a hot corona at ∼12 keV. No direct emission from the disc was found, possibly due to it being too cool. A high truncation radius for the disc, i.e. at ∼20–30 RG, was obtained from the analysis of the broadened profile of the Fe line in the reflection component. The significant detection of a blue-shifted Fe XXVI absorption line at ∼7 keV indicates weakly relativistic X-ray disc winds, which are typically absent in the hard state of X-ray binaries. By comparing the low flux observed during the outburst and the one expected in a conservative mass-transfer, we conclude that mass-transfer in the system is highly non-conservative, as also suggested by the wind detection. Finally, using the NICER  spectra alone, we followed the system while it was fading to quiescence. During the outburst decay, as the spectral shape hardened, the hotspot on the neutron star surface cooled down and shrank, a trend which could be consistent with the pure power-law spectrum observed during quiescence. [ABSTRACT FROM AUTHOR]

We present the pulsar timing analysis of the accreting millisecond X-ray pulsar SWIFT J1749.4 − 2807 monitored by NICER and XMM–Newton during its latest outburst after almost 11 yr of quiescence. From the coherent timing analysis of the pulse profiles, we updated the orbital ephemerides of the system. Large phase jumps of the fundamental frequency phase of the signal are visible during the outburst, consistent with what was observed during the previous outburst. Moreover, we report on the marginally significant evidence for non-zero eccentricity (e ≃ 4 × 10−5) obtained independently from the analysis of both the 2021 and 2010 outbursts and we discuss possible compatible scenarios. Long-term orbital evolution of SWIFT J1749.4 − 2807 suggests a fast expansion of both the NS projected semimajor axis (x), and the orbital period (P orb), at a rate of |$\dot{x}\simeq 2.6\times 10^{-13}\, \text{lt-s}\, \text{s}^{-1}$| and |$\dot{P}_{\rm orb}\simeq 4 \times 10^{-10}\, \text{s}\, \text{s}^{-1}$|⁠ , respectively. SWIFT J1749.4 − 2807 is the only accreting millisecond X-ray pulsar, so far, from which the orbital period derivative has been directly measured from appreciable changes on the observed orbital period. Finally, no significant secular deceleration of the spin frequency of the compact object is detected, which allowed us to set a constraint on the magnetic field strength at the polar caps of B PC < 1.3 × 108 G, in line with typical values reported for AMXPs. [ABSTRACT FROM AUTHOR]

INTRODUCTION: Aspergilloma is a non-invasive form of pulmonary aspergillosis usually presenting as a clump of mold in pre-existing cavitary lung disease. Aspergillus related lung diseases have been classified into four types, whose manifestation is often related to previous lung diseases and host immunologic status. CASE REPORT: Cases of cavitary pulmonary aspergillosis without any evidence of pre-existing cavities, are rarely reported. We present here a case of pulmonary aspergillosis in which cavity formation appeared apparently after the establishment of infection. CONCLUSIONS: The occurrence of atypical presentations and the importance of recognizing these unusual cases of pulmonary aspergilloma is discussed. [ABSTRACT FROM AUTHOR]

OBJECTIVE: The objective of this narrative review is to present a summary of current knowledge of host-fungal pathogen interaction focusing on the importance of the innate immune system in host defense against invasive fungal infections. In addition, the emergence of drug resistance in the treatment of invasive fungal infections has also been highlighted. MATERIALS AND METHODS: A literature review was conducted to identify articles documenting the role of the host innate immune system against fungal pathogen and the emergence of drug resistance in the treatment of invasive fungal infections. RESULTS: In this review, we provide an update from the most recent studies on the role of the host innate immune system against fungal pathogen and we also highlight the mechanisms that these pathogens use to evade the innate immune system. CONCLUSIONS: This review highlights the existence of different cellular mechanisms that, following the recognition of fungal PAMPS, induce the production of different sets of defense factors. The development of new diagnostic methods and antifungal drugs along with a better understanding of the host immune response are key approaches to controlling invasive fungal infections. [ABSTRACT FROM AUTHOR]

We detect millihertz quasi-periodic oscillations (mHz QPOs) using the Rossi X-ray Time Explorer (RXTE) from the atoll neutron-star (NS) low-mass X-ray binaries 4U 1608–52 and Aql X–1. From the analysis of all RXTE observations of 4U 1608–52 and Aql X–1, we find mHz QPOs with a significance level >3σ in 49 and 47 observations, respectively. The QPO frequency is constrained between ∼4.2 and 13.4 mHz. These types of mHz QPOs have been interpreted as being the result of marginally stable nuclear burning of He on the NS surface. We also report the discovery of a downward frequency drift in three observations of 4U 1608–52, making it the third source that shows this behaviour. We only find strong evidence of frequency drift in one occasion in Aql X–1, probably because the observations were too short to measure a significant drift. Finally, the mHz QPOs are mainly detected when both sources are in the soft or intermediate states; the cases that show frequency drift only occur when the sources are in intermediate states. Our results are consistent with the phenomenology observed for the NS systems 4U 1636–53 and EXO 0748–676, suggesting that all four sources can reach the conditions for marginally stable burning of He on the NS surface. These conditions depend on the source state in the same manner in all four systems. [ABSTRACT FROM AUTHOR]

We present the first-year data set of high-cadence, long-duration observations of the bright millisecond pulsar J0437−4715 obtained in the Argentine Institute of Radioastronomy (IAR). Using two single-dish 30 m radio antennas, we gather more than 700 hr of good-quality data with timing precision better than 1 μs. We characterize the white and red timing noise in IAR's observations, we quantify the effects of scintillation, and we perform single-pulsar searches of continuous gravitational waves, setting constraints in the nHz–μHz frequency range. We demonstrate IAR's potential for performing pulsar monitoring in the 1.4 GHz radio band for long periods of time with a daily cadence. In particular, we conclude that the ongoing observational campaign of the millisecond pulsar J0437−4715 can contribute to increase the sensitivity of the existing pulsar-timing arrays. [ABSTRACT FROM AUTHOR]

MAXI J1807+132 is a low-mass X-ray binary (LMXB) first detected in outburst in 2017. Observations during the 2017 outburst did not allow for an unambiguous identification of the nature of the compact object. MAXI J1807+132 that was detected in outburst again in 2019 and was monitored regularly with Neutron Star Interior Composition Explorer (NICER). In this paper, we report on 5 days of observations during which we detected three thermonuclear (Type-I) X-ray bursts, identifying the system as a neutron star LMXB. Time-resolved spectroscopy of the three Type-I bursts revealed typical characteristics expected for these phenomena. All three Type-I bursts show slow rises and long decays, indicative of mixed H/He fuel. We find no strong evidence that any of the Type-I bursts reached the Eddington Luminosity; however, under the assumption that the brightest X-ray burst underwent photospheric radius expansion, we estimate a <12.4 kpc upper limit for the distance. We searched for burst oscillations during the Type-I bursts from MAXI J1807+132 and found none (<10 per cent amplitude upper limit at 95 per cent confidence level). Finally, we found that the brightest Type-I burst shows a ∼1.6 s pause during the rise. This pause is similar to one recently found with NICER in a bright Type-I burst from the accreting millisecond X-ray pulsar SAX J1808.4–3658. The fact that Type-I bursts from both sources can show this type of pause suggests that the origin of the pauses is independent of the composition of the burning fuel, the peak luminosity of the Type-I bursts, or whether the NS is an X-ray pulsar. [ABSTRACT FROM AUTHOR]