Molybdenum disulfide, exfoliation methods and applications to photocatalysis: a review.

This review provides a deep analysis of the mechanical and optoelectronic characteristics of MoS2. It offers a comprehensive assessment of diverse exfoliation methods, encompassing chemical, liquid-phase, mechanical, and microwave-driven techniques. The review also explores MoS2's versatile applications across various domains and meticulously examines its significance as a photocatalyst. Notably, it highlights key factors influencing the photocatalytic process. Indeed, the enhanced visible light responsiveness of materials like MoS2 holds immense potential across a wide range of applications. MoS2's remarkable photocatalytic response to visible light, coupled with its notable stability, opens up numerous possibilities in various fields. This unique combination makes MoS2 a promising candidate for applications that require efficient and stable photocatalytic processes, such as environmental remediation, water purification, and energy generation. Its attributes contribute significantly to addressing contemporary challenges and advancing sustainable technologies.

The Effectiveness of COVID-19 Vaccines in Preventing Hospitalizations During the Delta Wave: A Patient-Population Study at a Major Referral Center.

Background and objective Coronavirus disease 2019 (COVID-19) has turned into a deadly global pandemic since its first discovery in Wuhan, China in December 2019. Safe and effective vaccines against COVID-19 have been introduced to the public and have been shown to reduce the severity of the disease and related mortality rates. COVID-19 vaccination was first introduced in Lebanon in mid-February 2021. In this study, we analyzed the effectiveness of vaccination against COVID-19-related hospitalization during the Delta wave at a major referral center in Lebanon. Methods This patient-population study was conducted on patients hospitalized with COVID-19 between July 1, 2021, and September 30, 2021, at the Rafik Hariri University Hospital (RHUH) in Beirut, Lebanon. Data were collected directly from the patients or from digitized records and included demographic characteristics (age, sex, and comorbidities), vaccination status, oxygen requirement, and outcomes. National vaccination data were collected from the daily bulletin provided by the Lebanese Ministry of Public Health. The data collected were analyzed using SPSS Statistics Version 19.0 (IBM Corp., Armonk, NY). Results A total of 289 patients were included in the study, of whom 90.3% were unvaccinated and 9.7% were vaccinated with at least one dose of a two-dose regimen. Only 4.5% of the 289 patients were fully vaccinated. Among those fully or partially vaccinated, the mean time from symptom onset to hospitalization was shorter but the hospital stay was longer compared to the unvaccinated group. The mortality rate was higher in the unvaccinated group (25.7%) compared to 14.3% among the vaccinated. The vaccine effectiveness compared to the national vaccination rate (22.5% in the population after the first and second dose) was 71.71% and 83.78% respectively. Conclusion The findings of this study highlight the fact that complete/partial vaccination against COVID-19 was highly protective against severe disease and hospitalization during the period with a predominance of the Delta variant in Lebanon.

Visceral Kaposi's Sarcoma as a Presentation in a Newly Diagnosed HIV-Infected Man: A Case Report.

Kaposi's sarcoma is an angioproliferative malignancy due to human herpesvirus-8 and is associated with immunosuppression. Although most cases are cutaneous and resolve with treatment of the underlying condition, few cases present with organ involvement and have a fulminant course. We present a case of a 24-year-old sexually active man who presented with fulminant visceral Kaposi's sarcoma, without cutaneous involvement. He presented with anasarca, high fever, hypoalbuminemia, and anemia on day five of antiretroviral therapy (ART). There was clinical improvement after the first dose of liposomal doxorubicin. However, given that he developed refractory pancytopenia, with disease relapse by the third week, he received a second dose of doxorubicin, with no clinical improvement, and the patient died with multi-organ dysfunction on day 22 of presentation. The main treatment is liposomal doxorubicin with ART, and the disease is typically associated with a poor prognosis.

Adenovirus Infection as a Cause of Fever of Unknown Origin and Allograft Dysfunction in a Kidney Transplant Recipient.

With the recent introduction of more potent modern immunosuppressive regimens in solid-organ transplant, new types of viral infections such as adenovirus are emerging as a potential cause for graft dysfunction and loss. We report a case of 41-year-old male patient with end-stage renal disease from recurrent kidney stones who underwent kidney transplant from a deceased 12-year-old female donor. He developed adenoviral infection with acute cystitis, microscopic hematuria, and necrotizing interstitial nephritis associated with graft dysfunction within the first month of the postoperative period. Diagnosis was made by graft biopsy that showed more than 60% necrosis with tubulointerstitial hemorrhage, thrombotic microangiopathy, and histologic features suggestive of viral infection with negative Cytomegalovirus and polyomavirus stains in the graft and elevated adenovirus PCR in the blood. Simultaneously, the patient had very low absolute total lymphocyte count of 70 cells/µL during which he received supratherapeutic tacrolimus at whole blood trough levels and mycophenolate mofetil. This prompted the tapering of immunosuppression and the discontinuation of all antimicrobial drugs. Within a 2-week period, the immune reconstitution was sufficient for the clearance of the infection and the subsequent gradual recovery of graft function.

The effects of VTA NMDA receptor antagonism on reward-related learning and associated c-fos expression in forebrain.

The mechanisms whereby reward-associated stimuli come to function as conditioned stimuli and acquire the capacity to activate the same neural regions activated by primary rewards (i.e., dopamine terminal regions) is not fully understood. We hypothesized that NMDA receptor stimulation in the VTA is necessary for the acquisition by a CS to both produce conditioned approach and activate dopamine terminal regions. Rats were tested in a conditioned approach protocol that consisted of light stimulus-food conditioning sessions (30 randomly presented light stimulus-food pellet pairings), a session with no stimuli or food and 1 session with only light stimulus (CS-only) presentations. Food trough head entries during the CS and just prior to the CS were recorded and a CS/pre-CS ratio indicating the conditioned approach response was calculated. Brain tissue was harvested after the CS-only session and processed for c-fos expression in prefrontal cortex area 2, nucleus accumbens core and shell and medial and lateral caudate. When bilateral intra-VTA microinjections of AP-5 (0, 0.25 or 0.5 µg) were made prior to each of the conditioning sessions the 0.5 µg AP-5 dose prevented the acquisition of conditioned approach; when 0.5 µg AP-5 injections were made prior to the CS-only test they failed to affect expression of the response. Also, 0.5 µg AP-5 prior to conditioning significantly reduced c-fos expression in response to the CS in nucleus accumbens core. These results suggest that VTA NMDA receptor stimulation is necessary for both the acquisition of reward-related learning and acquisition by the CS to activate dopamine terminal regions.

Behavioral activating effects of selective AMPA receptor antagonism in the ventral tegmental area.

In recent years, the role of glutamate in drug seeking has received increasing attention. The current study tested the hypothesis that NBQX (a selective AMPA receptor antagonist) in the ventral tegmental area (VTA) would reduce cocaine seeking. Rats were trained to lever-press for intravenous cocaine (1.0 mg/kg/injection). Two test conditions were used, each preceded by bilateral intra-VTA microinjections of vehicle, 0.5, 1.0 or 2.0 µg/0.5 µl of NBQX. In the without-conditioned-stimulus (without-CS) condition, neither active (cocaine-associated) nor inactive levers produced any consequences. In the with-CS condition, the active lever turned on the stimulus light (as during training) and the infusion pump, which delivered an injection of saline. NBQX produced 2 effects: (1) an overall increase in responding, and (2) an increase in active lever-pressing at the 0.5-µg dose in the with-CS condition. A separate group of rats was allowed to press 2 levers without reinforcement, and the 0.5-µg NBQX dose enhanced responding on both levers. These results failed to support the hypothesis that AMPA receptor antagonism in VTA would reduce cocaine seeking and suggest that such antagonism causes general activating effects and may enhance the capacity of cocaine-CSs to function as conditioned reinforcers.