Analysis of the relationship between drug susceptibility of Cryptococcus neoformans isolates and mortality in HIV-negative cryptococcal meningitis.

OBJECTIVES: The relationship between antifungal susceptibility and mortality of cryptococcal meningitis (CM) in HIV-negative patients is poorly understood. METHODS: We conducted a retrospective analysis of 1-year follow-up of 200 HIV-negative CM patients with an initial cerebrospinal fluid (CSF) culture for Cryptococcus neoformans. According to the cut-off values of minimum inhibitory concentration (MIC), two groups of five antifungal agents were classified: amphotericin B (AmB), ≤0.5 µg/mL, >0.5 µg/mL; 5-flucytosine (5-FC), ≤4 µg/mL, >4 µg/mL; fluconazole (FLU), ≤4 µg/mL, >4 µg/mL; itraconazole (ITR), ≤0.125 µg/mL, >0.125 µg/mL; and voriconazole (VOR), <0.25 µg/mL, ≥0.25 µg/mL. Comparisons were performed to analyse clinical features, laboratory, modified Rankin Scale (mRS) scores, and CSF findings under different prognosis outcomes in 1-year. RESULTS: All of Cryptococcus neoformans isolates were sensitive to AmB and VOR, most of them were sensitive to 5-FC and FLU (95.5% and 90.5%, respectively) while only 55.0% of them were susceptible to ITR. Minimum inhibitory concentrations of ITR and VOR were significantly related to baseline mRS scores. All-cause mortality was not significantly related to MICs in Cryptococcus neoformans strains. The combination of actual antifungal agents and two groups of the MICs values for antifungal agents had no significant effects on all-cause mortality. CONCLUSION: Most Cryptococcus neoformans isolates were sensitive to AmB, VOR, 5-FC, and FLU. Because of the small number of deaths, we are not able to comment on whether MIC is associated with mortality of CM in HIV-negative patients.

Clinical characteristics, treatment, and outcome of low-risk non-HIV-associated cryptococcal meningitis: A retrospective cohort study.

Although non-human immunodeficiency virus (HIV)-associated cryptococcal meningitis (CM) is a severe disease, there are still some non-HIV CM patients with a low risk of therapeutic failure. Recognizing clinical characteristics of low-risk non-HIV-associated CM may enable clinicians to treat non-HIV-associated CM more reasonably. According to the definition of low-risk non-HIV-associated CM in the 2010 Infectious Diseases Society of America guideline, a total of 220 non-HIV CM patients were divided into two groups (Group 1: 35 low-risk patients and Group 2: 185 non-low-risk patients). Clinical characteristics, treatment, and outcome were compared between the two groups. Compared with non-low-risk patients, low-risk patients had a lower rate of headache (82.9% vs. 95.7%, P = .012), cerebrospinal fluid (CSF) opening pressure (OP) at baseline (CSF OP < 250-mm H2O, 60.0% vs. 32.4%, P = .001), and baseline CSF cryptococcal count (median, 0 vs. 2376, P < .001), higher baseline CSF white blood cell (median, 130 vs. 90, P = .029) and CSF protein (median, 0.87 vs. 0.73, P = .011). Multivariate analysis showed that baseline CSF OP <250-mm H2O (OR: 2.545, 95% CI 1.168, 5.545, P = .019) was independently associated with low-risk for non-HIV-associated CM. The lengths of AMB-d-based induction therapy of low-risk patients (median, 20 days) were shorter (P < .001) than that of non-low-risk patients (median, 38 days). The successful outcome rate of low-risk patients was higher than non-low-risk patients (97.1% vs. 54.6%, P < .001). We demonstrated that non-HIV-associated CM patients with baseline CSF OP < 250-mm H2O were prone to the low-risk status.

This was a retrospective cohort study to find the features of low-risk non-human immunodeficiency virus (HIV)-associated cryptococcal meningitis (CM). We found that non-HIV-associated CM patients with baseline cerebrospinal fluid opening pressure <250-mm H2O were prone to low-risk status.

Seasonality and meteorological factors of HIV-negative cryptococcal meningitis in Guangdong Province, China.

OBJECTIVE: Information about the seasonal characteristics of human immunodeficiency virus (HIV)-negative cryptococcal meningitis (CM) is quite limited. The aim of this study was to explore the seasonality and meteorological factors of HIV-negative patients with CM. METHODS: We performed a retrospective study of 469 HIV-negative CM patients admitted to the Third Affiliated Hospital of Sun Yat-sen University, Guangzhou, Guangdong Province, China. Their initial onset symptoms of CM occurred from January 2011 to December 2020. The temperature, precipitation, sunlight, humidity and wind speed for the corresponding period and the associated topographic, ecological type and soil type parameters data were collected. The Poisson regression model was used to determine the meteorological factors associated with CM onset. The geographical detector method was used to detect other environmental factors associated with CM onset. RESULTS: CM onset did not showed a seasonal fluctuation, but was strongly associated with mean temperature (ß = .010, p = .028) and mean relative humidity (ß = -.011, p = .006). In the rainy season, only mean wind speed remained significantly associated with CM onset (ß = -.108, p = .041). In the dry season, mean temperature (ß = .014, p = .016), mean relative humidity (ß = -.016, p = .006) and hours of sunlight (ß = -.002, p = .016) were significantly associated with CM onset. Topographic, ecological type and soil type factors did not add explanatory power. CONCLUSIONS: Our findings add the knowledge about the environmental factors of HIV-negative CM. Meteorological factors, especially temperature and humidity, may be the main environmental factors affecting the onset of HIV-negative CM.

Neurological worsening during treatment of HIV-negative cryptococcal meningitis in a patient with Evans syndrome.

A 49-year-old woman with a rare autoimmune hematological disease, Evans syndrome, was admitted to the authors' hospital with immune reconstitution inflammatory syndrome-like reconstitution syndrome after effective antifungal therapy for cryptococcal meningitis. She initially improved after receiving corticosteroid treatment; after prednisone was tapered, her clinical presentation and brain imaging deteriorated but finally improved with the addition of thalidomide. Immune reconstitution inflammatory syndrome-like reconstitution syndrome is a rare complication in cryptococcal meningitis patients receiving immunosuppressive therapy. Thalidomide can be given in addition to corticosteroid therapy to effectively control the paradoxical inflammatory response and improve clinical outcomes.

The effect of serum uric acid, bilirubin, and albumin levels on antioxidant status in HIV-negative immunocompetent cryptococcal meningitis patients with post-infectious inflammatory response syndrome.

Oxidative imbalances have been observed in various neurological diseases. Despite the microbiological control in cryptococcal meningitis (CM), a proportion of previously healthy patients experience a clinical deterioration known as post-infectious inflammatory response syndrome (PIIRS). However, the antioxidant status in PIIRS remains unclear. In this study, we found that the serum antioxidant status of HIV-negative immunocompetent CM patients during PIIRS episodes was lower than that of healthy controls. There was a relationship between baseline serum indirect bilirubin levels and the development of PIIRS, and serum uric acid levels may indicate the severity of the disease during PIIRS episodes. Oxidative stress may play a role in the development of PIIRS.

This retrospective study on the serum antioxidant status in HIV-negative immunocompetent CM patients suggested that during PIIRS episodes, the serum antioxidant status in CM patients may be lower. CM patients with high baseline serum Ibil levels were more likely to develop PIIRS.

Reversible deafness and blindness in Cryptococcus gattii meningitis with a ventriculoperitoneal shunt: A case report and literature review.

Cryptococcus gattii (C. gattii) has been considered a leading cause of meningitis in immunocompetent hosts in tropical and subtropical regions. Visual loss is common but hearing impairment is relatively infrequent in C. gattii meningitis. Notably, there have been limited studies on the etiology, and especially therapy of auditory and ocular complications associated with C. gattii meningitis. Here we report a case of reversible deafness and blindness treated with a ventriculoperitoneal shunt (VPS) surgery in C. gattii meningitis. This case indicated that elevated intracranial pressure (ICP) may play a role in the concurrent hearing and vision impairments associated with C. gattii meningitis and the early VPS surgery after the initiation of the antifungal therapy may effectively improve both hearing and vision in this condition.

Protein Condensate Formation via Controlled Multimerization of Intrinsically Disordered Sequences.

Many proteins harboring low complexity or intrinsically disordered sequences (IDRs) are capable of undergoing liquid-liquid phase separation to form mesoscale condensates that function as biochemical niches with the ability to concentrate or sequester macromolecules and regulate cellular activity. Engineered disordered proteins have been used to generate programmable synthetic membraneless organelles in cells. Phase separation is governed by the strength of interactions among polypeptides with multivalency enhancing phase separation at lower concentrations. Previously, we and others demonstrated enzymatic control of IDR valency from multivalent precursors to dissolve condensed phases. Here, we develop noncovalent strategies to multimerize an individual IDR, the RGG domain of LAF-1, using protein interaction domains to regulate condensate formation in vitro and in living cells. First, we characterize modular dimerization of RGG domains at either terminus using cognate high-affinity coiled-coil pairs to form stable condensates in vitro. Second, we demonstrate temporal control over phase separation of RGG domains fused to FRB and FKBP in the presence of dimerizer. Further, using a photocaged dimerizer, we achieve optically induced condensation both in cell-sized emulsions and within live cells. Collectively, these modular tools allow multiple strategies to promote phase separation of a common core IDR for tunable control of condensate assembly.

Post-Infectious Inflammatory Response Syndrome in an HIV-Negative Immunocompetent Elderly Patient With Cryptococcal Meningitis: A Case Report and Literature Review.

We report a previously healthy 82-year-old male with cryptococcal meningitis (CM) who represented neurological deterioration due to post-infectious inflammatory response syndrome (PIIRS) occurring in 4 months after initial antifungal therapy. He was treated with corticosteroids for 2 months and recovered clinically. However, the clinical manifestation, cerebrospinal fluid (CSF), and brain magnetic resonance imaging (MRI) results got worse again on the next day after corticosteroid withdrawal. The analysis of inflammatory cytokines and culture on CSF, as well as brain MRI, still suggested a diagnosis of PIIRS. Therefore, corticosteroid therapy was used again and he subsequently obtained a complete resolution of symptoms.

Ceramide-Fabricated Co-Loaded Liposomes for the Synergistic Treatment of Hepatocellular Carcinoma.

Combination therapy is one of the important methods to improve therapeutic effect on the treatment of hepatocellular carcinoma (HCC). Sorafenib (SF) is a canonical US Food and Drug Administration-approved multikinase molecule inhibitor against HCC. However, therapeutic benefit with Sorafenib alone was usually unsatisfactory. Ceramide (CE) is an endogenous bioactive sphingolipid, which has a strong potential to suppress various tumors. The combination of SF and CE was hoping to exert maximum synergistic antitumor effect through different tumor-suppressible mechanisms. In this respect, SF and CE co-loaded liposomes (SF/CE-liposomes) were developed to verify synergistic antitumor efficacy. The optimal molar ratio of SF and CE was determined through combination index. SF/CE-liposomes were prepared by thin-film hydration method, which exhibited spherical or ellipsoidal shape. Particle size of SF/CE-liposomes was 174 ± 4 nm with homogeneous distribution. Release profile of SF demonstrated that addition of CE imposed no significant impact on the release of SF. SF/CE-liposomes exhibited acceptable stability in different media and desirable storage stability over 30 days at 4°C. In vitro cellular uptake confirmed that SF/CE-liposomes could be efficiently internalized into HepG2 cells. In vitro cytotoxicity evaluation indicated that SF/CE-liposomes exhibited higher cytotoxicity on HepG2 cells. IC50 value of SF/CE-liposomes was 11.5 ± 0.44 µM, which was significantly lower than that of SF-liposomes (**p < 0.01). Evaluation of in vivo synergistic effect on H22-bearing mice verified that SF/CE-liposomes achieved robust antitumor activity in preventing tumor growth. All results suggested that SF/CE-liposomes might be served as an efficient co-delivery system for improving therapeutic efficacy of HCC.

Tumor-Microenvironment Relaxivity-Changeable Gd-Loaded Poly(L-lysine)/Carboxymethyl Chitosan Nanoparticles as Cancer-Recognizable Magnetic Resonance Imaging Contrast Agents.

Magnetic resonance imaging (MRI) contrast agents with tumor-microenvironment changeable relaxivity are effective to increase the sensitivity and selectivity of MRI in tumor diagnosis. In this study, pH-sensitive Gd-loaded Poly(L-lysine)/ Carboxymethyl Chitosan Nanoparticles (Gd-PCNPs) were developed as relaxivity-changeable MRI contrast agents based on the "on­off" switchable strategy. The "on­off" switchable nano-contrast agents were capable of releasing Gd3+ in response to physical stimulation, with structure transformed. Gd-PCNPs could responsively disassemble in an acidic tumor-microenvironment and increase the exchange of protons between water molecules and Gd3+ ions, thus selectively enhance the relaxivity in tumor area. Gd-PCNPs were self-assembled via electrostatic interaction between poly(L-lysine)-diethylenetriamine pentaacetic acid-gadolinium and pH-sensitive carboxymethyl chitosan (CMCS). Gd-PCNPs exhibited spherical shape with uniform particle size distribution (166.00 ± 1 .71 nm) and negative zeta potential (­13.2 ± 4.7 mV). The relaxivity of Gd-PCNPs increased from 6.618 mM­1 · s­1 to 10.008 mM­1 · s­1 when the pH values decrease from 7.4 to 6.0, which was higher than Magnevist® (3.924 mM­1 · s­1 at both pH 7.4 and 6.0 (p <0 05). The changeable relaxivity of Gd/PCNPs would result in enhanced tumor/normal tissue signal contrast, which was verified by in vivo MRI test. In vivo MRI test showed that the signal of Gd-PCNPs was significantly enhanced with prolonged imaging time in tumor tissue compared to Magnevist® (p <0 05). Furthermore, Gd-PCNPs exhibited unobvious in vitro cytotoxicity under the experimental concentrations in B16 cells. No obvious damage was observed in the different tissues of mice. These results indicated that the relaxivity-changeable Gd-PCNPs exhibited demonstrated sensitivity and selectivity in tumor diagnosis with a great potential as a novel MRI contrast agent.

Polymeric complex micelles based on the double-hydrazone linkage and dual drug-loading strategy for pH-sensitive docetaxel delivery.

Stimuli-triggered drug release and improved drug loading are two key prerequisites in the preparation of nano-drug delivery systems. Herein, we constructed the first pluronic P123-double (d)-hydrazone bond (hyd)-docetaxel (DTX)/DTX complex micelles (P123-d-hyd-DTX/DTX) which integrated the highly pH-sensitive strategy and the dual drug-loading pattern in one platform. We synthesized pluronic P123-double (d)-hydrazone bond (hyd)-docetaxel (DTX) conjugates (P123-d-hyd-DTX) by conjugating DTX to the PEO chains of P123 via two hydrazone linkages in the backbone for the first time. An increase in the number of hydrazone linkages within the unimolecular conjugate was conducive to improve the pH sensitivity of conjugated-based micelles. Besides, aiming at improving drug loading, the dual drug-loading strategy (chemical conjugation and physical encapsulation) was adopted. Namely, pH-sensitive P123-d-hyd-DTX was used as a vehicle to further encapsulate DTX for preparing P123-d-hyd-DTX/DTX complex micelles. The resulting P123-d-hyd-DTX/DTX micelles exhibited intact spherical shape, uniform particle size distribution (110.37 nm) and higher drug loading (12.64%). The release study in vitro confirmed that P123-d-hyd-DTX/DTX micelles and P123-d-hyd-DTX micelles (as a control) showed highly pH-responsive release properties. In particular at pH 6.5, almost 90.9% and 75% of DTX was released within 48 h, respectively. Compared to P123-d-hyd-DTX micelles, P123-d-hyd-DTX/DTX complex micelles exhibited higher proliferation inhibition effects on B16F10 cells (p < 0.01), while the cytotoxicity of P123-d-hyd-DTX/DTX complex micelles was slightly inferior to that of free DTX (p < 0.05). In the xenograft B16F10 melanoma model, P123-d-hyd-DTX/DTX complex micelles suppressed tumor growth more effectively than Duopafei® (p < 0.01) and P123-d-hyd-DTX micelles (p < 0.05), without causing obvious adverse effects. Overall, the novel polymeric complex micelle based on double-hydrazone bond and dual drug-loading strategies was a promising delivery platform to improve therapeutic efficiency and decrease side effects in cancer treatments.

pH-Sensitive carboxymethyl chitosan-modified cationic liposomes for sorafenib and siRNA co-delivery.

Combination of chemotherapeutic drug and small interfering RNA (siRNA) can affect multiple disease pathways and has been proven effective in suppressing tumor progression. Co-delivery of drug and siRNA within a same nanocarrier is a vital means in this field. The present study aimed at the development of a pH-sensitive liposome to co-deliver drug and siRNA to tumor region. Driven by the electrostatic interaction, the pH-sensitive material, carboxymethyl chitosan (CMCS), was coated onto the surface of the cationic liposome (CL) preloaded with sorafenib (Sf) and siRNA (Si). To evaluate whether the resulting CMCS-modified Sf and siRNA co-delivery cationic liposome (CMCS-SiSf-CL) enhanced antitumor efficiency after systematic administration, in vitro and in vivo experiments were evaluated in HepG2 cells and the H22 cells-bearing Kunming mice model. The experimental results demonstrated that CMCS-SiSf-CL was able to condense siRNA efficiently and protect siRNA from being degraded by serum and RNase. The release rate of Sf from CMCS-modified liposome exhibited pH-sensitive release behavior. Furthermore, in vitro cellular uptake results showed that CMCS-SiSf-CL yielded higher fluorescence intensity at pH 6.5 than at pH 7.4, and that siRNA could be delivered to tumor site by CMCS-SiSf-CL in vivo. The in vivo antitumor efficacy showed that CMCS-Sf-CL inhibits tumor growth effectively when compared with free Sf solution. In current experimental conditions, this liposomal formulation did not show significant toxicity both in vitro and in vivo. Therefore, co-delivering Sf with siRNA by CMCS-SiSf-CL might provide a promising approach for tumor therapy.