Combination immunotherapy of MAb B6.1 with fluconazole augments therapeutic effect to disseminated candidiasis

We recently reported that IgM MAb B6.1, specific for β-1, 2-mannotriose on the cell wall of Candida albicans, is therapeutic to disseminated candidiasis due to C. albicans. In the current study, we examined if MAbB6.1 enhances therapeutic effect of fluconazole (FLC) to the disseminated disease. To assess the combination effect, determination by the kidneys-colony forming unit and survival times were used. Results showed that the therapeutic effect of FLC on mice with disseminated candidiasis was dose-dependent, but a FLC dose at 0.8 mg/kg body weight of mice was ineffective. To determine combination effect, mice treated intraperitoneally with a combination of FLC plus MAb B6.1 at 1 h post-infection — a condition of developing partial therapeutic activity — enhanced survival times beyond the effect by only antibody (p < 0.05). The resulting MST (mean survival times) value from the combinationreceived mice was almost the same as MST value from 3.2 mg FLC dose-given animals (p < 0.05). Another combination of 1.6 mg FLC dose and B6.1 reduced severity of the disseminated disease at almost the same rate as combination efficacy of 0.8 mg FLC dose plus B6.1. This data indicates that B6.1 acts in concert with FLC and that this combination therapy augments protection, which suggests a possibility of reducing FLC dose. The augmentation response was specific because an irrelevant IgM MAb S9 was not effective to the disseminated disease. Thus, our present studies demonstrate that this combination immunotherapy may be a way of solving the problem of limited antifungal drug choices caused by drug-resistant C. albicans.     

Immunomodulator tuftsin increases the susceptibility of Cryptococcus neoformans to liposomal amphotericin B in immunocompetent BALB/c mice

The co-administration of immunomodulators and antibiotics has been proved very successful for treatment of opportunistic infectious diseases. In the present study, we evaluated the combination of liposomal amphotericin B (lip-Amp B) and immunomodulator tuftsin to cure Cryptococcus neoformans infection in BALB/c mice. Mice infected with C. neoformans were treated with Amp B deoxycholate and tuftsin free or tuftsin-loaded Amp B liposomes. The results of the present study demonstrated higher efficacy of tuftsin-loaded Amp B liposomes against experimental murine cryptococcosis, in terms of enhanced survival rate and reduced fungal burden in organs (lungs and brain) of the treated mice. Interestingly, pre-treatment of mice with liposomal tuftsin before challenging them with the C. neoformans infection resulted in 100% survival of the treated animals followed by treatment with lip-Amp B. Immunomodulator-based therapy seems likely to be more beneficial for treatment of fungal infectious diseases.     

Prophylactic Role of Liposomized Chloroquine Against Murine Cryptococcosis Less Susceptible to Fluconazole

No HeadingPurpose. The prophylactic role of liposomized chloroquine (lip-CQ) has been assessed against less susceptible Cryptococcus neoformans infection in murine model.Methods. In the current study, we investigated the antifungal activity of lip-CQ against C. neoformans in macrophages cell line (J 774) and murine model. Mice were pretreated with free as well as liposomized formulations of CQ at various doses. The anticryptococcal activity of fluconazole was compared in mice with or without CQ pretreatment. The efficacy of CQ prophylaxis was assessed by survival as well as colony forming units (cfu) in brain and lungs of treated mice.Results. Fluconazole alone was not found significantly effective against C. neoformans in both in vitro and in vivo studies. However, the antifungal activity of fluconazole increases in chloroquine-pretreated mice. Lip-CQ was found to be more effective in comparison to the same dose of free chloroquine in reducing fungal burden from macrophages in vitro and lungs and brain of C. neoformans infected mice.Conclusions. The enhanced prophylactic activity of lip-CQ seems due to rapid uptake of drug-containing liposomes by macrophages. The liposome-mediated accumulation of CQ in macrophages makes the environment unfavorable (alkaline) for the intracellular multiplication of C. neoformans. Moreover, the increased incidence of multidrug resistance and diversity of pathogenic microorganisms inhibited or killed by CQ makes it the drug of choice for prophylactic therapy.     

Anti-inflammatory potential of carotenoid meso-zeaxanthin and its mode of action

Abstract

Context: meso-Zeaxanthin (MZ) is a xanthophyll carotenoid with profound antioxidant activity.

Objective: Oxidative stress plays a decisive role in numerous degenerative diseases including cancer. The present study evaluates anti-inflammatory effect of MZ.

Materials and methods: Balb/c mice were treated with different doses of MZ (50 and 250?mg/kg b.wt, orally) 5?d before subcutaneous injection of carrageenan (1%), dextran (1%), and formalin (2%). Paw edema formation in MZ-treated and -untreated animals was measured using vernier calipers. Anti-inflammatory activity of MZ against lipopolysaccharide (LPS)-induced inflammatory model was studied by culturing macrophages in the presence and absence of LPS (5?μg/ml) and different concentrations of MZ (5, 10, and 25?μg/ml). After 24?h, the effect of MZ on pro-inflammatory cytokine levels in macrophages was analyzed by ELISA and its effect on various inflammatory genes was studied by RT-PCR.

Results: MZ administration at different doses significantly (p?<?0.001) inhibited paw edema induced by carrageenan, dextran, and formalin in mice. MZ also exhibited profound anti-inflammatory effect against LPS-induced inflammation in macrophages. Increased production of nitric oxide, C-reactive proteins, and various pro-inflammatory cytokines (TNF-α, interleukin-1β, and interleukin-6) in LPS-stimulated macrophages was significantly reduced by MZ treatment. Moreover, LPS-stimulated up-regulated mRNA expression of various inflammatory mediator genes like COX-2, TNF-α, and iNOS was down-regulated by MZ administration.

Discussion and conclusion: MZ has potent anti-inflammatory effect which can be due to its down-regulated expression of various inflammatory mediator genes. Since cancer is considered as an inflammatory disease, the present study points towards the importance of MZ in chemo-preventive strategy.     

Cytotoxicity and anti-Leishmania amazonensis activity of Citrus sinensis leaf extracts

Context: Leishmania amazonensis is the main agent of diffuse cutaneous leishmaniasis, a disease characterized by lesional polymorphism and the commitment of skin surface. Previous reports demonstrated that the Citrus genus possess antimicrobial activity.

Objective: This study evaluated the anti-L. amazonensis activity of Citrus sinensis (L.) Osbeck (Rutaceae) extracts.

Materials and methods: Citrus sinensis dried leaves were subjected to maceration with hexane (CH), ethyl acetate (CEA), dichloromethane/ethanol (CD/Et – 1:1) or ethanol/water (CEt/W – 7:3). Leishmania amazonensis promastigotes were treated with C. sinensis extracts (1–525?μg/mL) for 120?h at 27?°C. Ultrastructure alterations of treated parasites were evaluated by transmission electron microscopy. Cytotoxicity of the extracts was assessed on RAW 264.7 and J774.G8 macrophages after 48-h treatment at 37?°C using the tetrazolium assay. In addition, Leishmania-infected macrophages were treated with CH and CD/Et (10–80?μg/mL).

Results: CH, CD/Et and CEA displayed antileishmanial activity with 50% inhibitory activity (IC₅₀) of 25.91?±?4.87, 54.23?±?3.78 and 62.74?±?5.04?μg/mL, respectively. Parasites treated with CD/Et (131.2?μg/mL) presented severe alterations including mitochondrial swelling, lipid body formation and intense cytoplasmic vacuolization. CH and CD/Et demonstrated cytotoxic effects similar to that of amphotericin B in the anti-amastigote assays (SI of 2.16, 1.98 and 1.35, respectively). Triterpene amyrins were the main substances in CH and CD/Et extracts. In addition, 80?μg/mL of CD/Et reduced the number of intracellular amastigotes and the percentage of infected macrophages in 63% and 36%, respectively.

Conclusion: The results presented here highlight C. sinensis as a promising source of antileishmanial agents.     

Thymus peptides regulate activity of RAW 264.7 macrophage cells: inhibitory analysis and a role of signal cascades

Objectives: The aim of this study was to reveal T-lymphocyte-independent mechanisms of thymic peptide-mediated immunomodulation.

Methods: The effects of two thymic peptides— thymulin and thymopentin were studied in cultured RAW 264.7 macrophages (lipopolysaccharide-stimulated or unstimulated) by measuring cytokine production and signal protein levels.

Results: Both peptides increased proinflammatory cytokine secretion by unstimulated RAW 264.7 macrophages and these effects were blocked by the NF-κB cascade inhibitor, stress-activated protein kinase (SAPK)/JNK cascade inhibitor and, to a lesser extent, Toll-like 4 receptor activity inhibitor. In macrophages stimulated by bacterial lipopolysaccharide, peptides alone did not affect cytokine secretion, but significantly enhanced effects of each of the inhibitors. Thymopentin increased activation of both NF-κB and SAPK/JNK cascades in unstimulated macrophages, while thymulin significantly decreased activation of the SAPK/JNK but not NF-κB cascade in LPS-stimulated macrophages. Thymulin and thymopentin increased production of the heat shock protein HSP72 both in LPS-stimulated and unstimulated cells.

Conclusions: Thymulin and thymopentin are effective anti-inflammatory modulators with direct actions on innate immune cells; the effects involve multiple signal cascades, including NF-κB and SAPK/JNK pathways. Since signaling cascades are now considered to be targets for new therapies, thymic peptides may be prospective modulators of signaling cascades, acting alone or in combination with other agents.     

Curcumin suppresses inflammatory cytokines and heat shock protein 70 release and improves metabolic parameters during experimental sepsis

Context: Curcumin has been reported to have anti-inflammatory, antioxidant and hypoglycaemic properties, besides reducing mortality in sepsis.

Objective: This study evaluates the biological activities of a curcumin dispersion formulated by spray-drying in experimental sepsis.

Materials and methods: Male Wistar rats were subjected to sepsis by caecal ligation and puncture (CLP), controls were sham operated. The animals were treated with curcumin dispersion (100?mg/kg, p.o.) or water for 7 days prior to CLP and at 2?h after surgery. One group was used to analyze curcumin absorption through HPLC; another had the survival rate assessed during 48?h; and from a third group, blood was collected by decapitation to analyze metabolic and inflammatory parameters.

Results: The plasma curcumin levels reached 2.5?ng/mL at 4?h, dropped significantly (p?p?p?p?p?p?Discussion and conclusion: Our results show that the curcumin dispersion dose employed was not detrimental to the septic rats. In fact, it temporarily increased their survival rate, improved important metabolic parameters, reduced proinflammatory cytokines and HSP70 production.     

Protective effect of Artin M from extract of Artocarpus integrifolia seeds by Th1 and Th17 immune response on the course of infection by Candida albicans

The immunoregulatory effect of Artin M and jacalin from extract of Artocarpus integrifolia seeds (jack extract) against infection with Candida albicans was investigated. Swiss mice received jack extract containing 500 μg protein/ml PBS intraperitoneally (i.p.) or PBS alone and after 72 h were infected i.p. with C. albicans CR15 (10⁷) and sacrificed after 30 min, 2, 6, 24, and 72 h. ELISA analysis revealed that in jack extract-treated mice IFN-γ was predominantly produced versus IL-10 in control mice. These results suggest that jack extract induced a protective immune response, since C. albicans clearance was complete at 72 h postinfection. Jack extract presents two lectins (Artin M and jacalin) with distinct biological properties. Artin M was able to induce IL-12 production by macrophages. Also, Artin M in different concentrations, associated with jacalin or in jack extract induced both IFN-γ and IL-17 production. As a consequence, phagocytic and candidacidal activity increased significantly. Alanine aminotransferase activity (ALT) was used as parameter for damage of the liver. The activity of ALT correlated with inoculum size that increased significantly in control group, however, mice pretreated with jack extract 3 days before infection presented normal ALT. Mice pretreated with jack extract that received a lethal inoculum of Candida presented 90% survival versus 20% among controls or mice pretreated with jacalin. Thus, the results suggest that Artin M by itself, associated with jacalin or present in jack extract is able to induce protective Th1 and Th17 immune responses against Candida albicans infection.     

Peptides with indirect in vivo activity against an intracellular pathogen: selective lysis of infected macrophages

Abstract: A collection of natural peptides, simplified analogs of natural peptides, de novo amphipathic peptides and de novo amphipathic peptides composed of 50–80% α,α‐dialkylated glycines (α,α‐Dags) were synthesized on solid‐phase resin as the C‐terminus amides using N‐α‐fluorenylmethyloxycarbonyl protection. The synthesis of the peptides rich in α,α‐Dags used acid fluoride coupling methods. The peptides show antimicrobial activity against Escherichia coli and Staphylococcus aureus but no direct antimicrobial activity against Brucella abortus at 100 µm in vitro. However, in vivo treatment with several of these peptides results in significant reductions of B. abortus in chronically infected immune BALB/c mice relative to infected control animals. The chronically infected mice were susceptible to peptide toxicity at much lower peptide doses than control animals. The highest nonlethal dose for infected mice was only 25 µg for melittin, whereas 500 µg doses were nonlethal for many of the other peptides. Several of the α,α‐Dag‐rich peptides selectively destroy B. abortus‐infected murine macrophages in vitro. Thus, these peptides apparently reduce the bacterial load in vivo by destroying a portion of the infected macrophages and exposing the sequestered bacteria to the immune response in the mice.     

Nanoparticle formulation increases Syzygium cumini antioxidant activity in Candida albicans-infected diabetic rats

Context: Syzygium cumini (L.) Skeels (Myrtaceae) is a medicinal plant widely used in folk medicine for the treatment of diabetes mellitus (DM). However, studies on the use of this plant and of nanoparticle formulations against DM-related fungal infections are scarce.

Objective: To evaluate the effect of the treatments with aqueous seed extract of S. cumini (ASc) and ASc-loaded polymeric nanoparticles (NPASc) on biochemical parameters in Candida albicans-infected diabetic rats.

Materials and methods: Male Wistar rats were divided into eight groups: Control, DM, C. albicans, C. albicans?+?ASc, C. albicans?+?NPASc, DM?+?C. albicans, DM?+?C. albicans?+?ASc and DM?+?C. albicans?+?NPASc. Rats were daily treated with ASc or NPASc (100?mg/kg) for 21 days. Biochemical parameters in serum and urine, advanced oxidation protein product (AOPP) and TBARS levels in the serum, kidney, liver and pancreas and N-acetyl-β-d-glucosaminidase (NAG) activities in kidney and urine were evaluated.

Results: Biochemical and oxidative stress parameters increased in rats with DM and/or candidiasis. NPASc was more effective than ASc in decreasing glucose (56%), cholesterol (33%) and creatinine (51%) levels; serum (16%) and pancreatic (46%) AOPP and renal (48%) TBARS levels when compared with DM?+?C. albicans group. In C. albicans group, both treatments decreased NAG activity but did not decrease creatinine levels.

Conclusions: These data suggest that the use of nanotechnology is able to improve plant extract properties such as antioxidant activity that may be useful in diabetes-related complications.     

Effect of Liposomal and Free Bisphosphonates on the IL-1β, IL-6 and TNFα Secretion from RAW 264 Cells in Vitro

Purpose. In order to evaluate the possible antiinflammatory action of bisphosphonates, the effect of the drugs on the secretion of proinflammatory cytokines (IL-l, IL-6 and TNF) from macrophages was studied. Liposomes or high concentration of extracellular calcium was used to enhance the intracellular delivery of bisphosphonates. Methods. RAW 264 cells were used as macrophage model, and they were induced with lipopolysaccharide to produce the cytokines. The cytokine concentrations in the culture supernatants were measured with time-resolved fluoroimmunoassay. Results. As a free drug, clodronate and pamidronate, but not etidronate, inhibited LPS-stimulated secretion of the cytokines from macrophage-like RAW 264 cells. Low concentrations of pamidronate, however, induced the IL-6 secretion, and the cytokine inhibitory action at the higher concentrations of pamidronate was attributed to cytotoxicity of the compound. The cytokine induction or toxic effects were not observed with clodronate or etidronate. When the drugs were encapsulated in negatively charged unilamellar liposomes, the inhibitory potency of both clodronate and etidronate enhanced by a factor of 10-20, while that of pamidronate was not increased. The complex formation of bisphosphonates with extracellular calcium, although enhancing the uptake of the compounds by macrophages, did not considerably increase their cytokine inhibitory potency. Conclusions. Bisphosphonates have inhibitory action on cytokine secretion by macrophages. The non-cytotoxic cytokine inhibition by liposome encapsulated clodronate could be beneficial in local inflammatory diseases, where the inflammation is sustained by the excessive amounts of inflammatory cytokines produced by activated macrophages.     

The effect of intracellular delivery of catalase and antisense oligonucleotides to NF-κB using albumin microcapsules in the endotoxic shock model

Microencapsulated (MC) catalase has been shown to inhibit H₂O₂ and tumor necrosis factor (TNF) in vitro after endotoxin stimulation. It is the purpose of this study to determine whether MC catalase improves pro-inflammatory cytokine inhibition and mortality in an endotoxic shock model in vivo. We also examined whether MC catalase and antisense oligonucleotides (ASO) to nuclear factor κB (NF-κB) together improved survival by inhibiting pro-inflammatory cytokines using different mechanisms. Methods: Albumin microcapsules containing catalase and ASO to NF-κB were prepared 2–7 μm in size by using a Büchi spray dryer. Progressively increasing doses of MC catalase, MC ASO to NF-κB, and the combination were given to rats before the administration of Escherichia coli endotoxin. Results demonstrated 60% survival in rats given 15?mg/kg MC catalase, 70% survival with 20?mg/kg MC ASO NF-κB, and 80% survival with the combination. TNF was inhibited by 53% in the MC catalase group 4?h after endotoxin administration, 43% in the ASO NF-κB group, and 78% in the combination group compared to controls. In conclusion, this study demonstrates the effectiveness of MC intracellular delivery of the naturally occurring antioxidant catalase in improving animal survival. The addition of ASO to NF-κB improved both cytokine inhibition and animal survival in endotoxic shock.     

Biodistribution of Amphotericin B When Delivered Through Cholesterol Hemisuccinate Vesicles in Normal and A. Fumigatus Infected Mice

Purpose. This study compared the biodistribution of two amphotericin B formulations in normal and Aspergillus infected mice. Amphotericin B cholesterol hemisuccinate vesicles (ABCV) which reduces the toxicity of amphotericin B and thereby enhances its therapeutic efficacy in a murine model of aspergillosis was compared with conventional amphotericin B deoxycholate suspension (AmB_DOC). Methods. ABCV (12 mg/kg wt) and AmB_DOC (2 mg/kg wt) were intravenously administered to normal and A.fumigatus infected mice. The concentration of amphotericin B in plasma and other organs was determined at different time points. Results. It was observed that ABCV had a significantly different pharmacokinetic profile compared to conventional amphotericin B. In comparison to AmB_DOC significantly lower levels of amphotericin B were observed in kidneys and plasma, the major target organs of toxicity. Animals receiving ABCV demonstrated high levels of amphotericin B in liver (38% retention till 48 h) and spleen (2.6% retention till 48 h) in comparison to AmB_DOC (7.3% and 0.21% retention in liver and spleen respectively till 48 h). Biodistribution studies of ABCV in infected mice demonstrated that there was a moderate enhancement in levels of amphotericin B in liver, spleen, lungs and kidneys as compared to normal mice and the plasma levels were reduced. However, such observations were not made after AmB_DOC administration to infected mice except for kidneys in which there was a marked increase in uptake as compared to normal mice. Conclusions. Our results suggest that prolonged retention of high concentrations of ABCV in reticuloendothelial system organs is the reason for its reduced toxicity. Enhanced localization of the drug at the infected site may lead to improvement in therapeutic efficacy.     

Anti-inflammatory effect of Arnica montana in a UVB radiation-induced skin-burn model in mice

Abstract

Background: ultraviolet radiation types A and B (UV) (400–315nm and 315–280nm respectively) are the main components present in sunlight known to cause skin injuries. Arnica montana is a plant that has been widely studied for containing anti-inflammatory, healing and analgesic properties capable of preventing or ameliorating lesions. Here, we investigated the therapeutic effect of topical application of Arnica montana after UVB-induced cutaneous injuries in mice.

Methods: mice were exposed to UVB radiation (Philips TL40W/12 RS lamp) in a period of 3?hours. After one hour of radiation exposure, the animals were treated with topical application of Arnica montana ointment (250?mg/g) in the ear. At the time of 16?hours after treatment, the parameters of edema, oxidative stress and inflammatory reaction were measured in the ear of mice.

Results: our results demonstrated that topical treatment with Arnica montana reduced the UVB-induced inflammatory response as demonstrated by the reduction of ear edema, inhibition of myeloperoxidase activation, decrease of nuclear factor kappa B levels and reduction of proinflammatory cytokines levels, such as interleukin-1beta, interleukin-6, tumour necrosis factor-alpha and interferon-gamma. In addition, Arnica montana ameliorated oxidative damage mediated by UVB radiation, as demonstrated by the reduction of lipid peroxidation, protein oxidation and increase of tissue antioxidant capacity and glutathione levels in the ear.

Conclusion: we concluded that Arnica montana ointment is effective in alleviating the auricular inflammatory process and oxidative damage induced by acute UVB radiation, sustaining the traditional use of Arnica montana for the treatment of skin disorders.     

Antimicrobial activity of Buchenavia tetraphylla against Candida albicans strains isolated from vaginal secretions

Context: Buchenavia tetraphylla (Aubl.) RA Howard (Combretaceae: Combretoideae) is an ethnomedicinal plant with reported antifungal action.

Objective: This study evaluates the antimicrobial activity of B. tetraphylla leaf extracts against clinical isolates of Candida albicans. The morphological alterations, combinatory effects with fluconazole and the cytotoxicity of the active extract were analyzed.

Materials and methods: Extracts were obtained using different solvents (hexane: BTHE; chloroform: BTCE; ethyl acetate: BTEE; and methanol: BTME). Antimicrobial activity was determined by the broth microdilution method using nine strains of C. albicans isolated from vaginal secretions and one standard strain (UFPEDA 1007).

Results: All extracts showed anti-C. albicans activity, including against the azole-resistant strains. The MIC values ranged from 156 to 2500?μg/mL for the BTHE; 156 to 1250?μg/mL for the BTCE; 625 to 1250?μg/mL for the BTME and 625?μg/mL to 2500?μg/mL for the BTEE. BTME showed the best anti-C. albicans activity. This extract demonstrated additive/synergistic interactions with fluconazole. Scanning electron microscopy analysis suggested that the BTME interferes with the cell division and development of C. albicans. BTME showed IC₅₀ values of 981 and 3935?μg/mL, against J774 macrophages and human erythrocytes, respectively. This extract also enhanced the production of nitric oxide by J774 macrophages.

Discussion and conclusion: Buchenavia tetraphylla methanolic extract (BTME) is a great source of antimicrobial compounds that are able to enhance the action of fluconazole against different C. albicans strains; this action seems related to inhibition of cell division.     

Anti-inflammatory effects of curcumin are associated with down regulating microRNA-155 in LPS-treated macrophages and mice

Context: The natural polyphenolic compound curcumin has been proved to modulate innate immune responses and possess anti-inflammatory properties. Nevertheless, the mechanism remains poorly understood, particularly regarding curcumin-regulated miRNAs under inflammatory response.

Objective: This study investigates the role of miRNA-155 in the effects of curcumin on inflammatory response in cell and a mouse model.

Materials and methods: The anti-inflammatory activity of curcumin (5, 10 and 15?μM, 2?h) in lipopolysaccharide (LPS, 200?ng/mL)-induced cells were measured by quantitative PCR. The animals were treated orally by 20?mg/kg curcumin for 3?days before an LPS intraperitoneal injection (10?mg/kg, 16?h). MicroRNA (miRNA) expression and the underlying molecular mechanisms were assessed using transfection technique and western blotting.

Results and discussion: Curcumin efficiently inhibited LPS-induced cytokines (TNF-α, IL-6) and microRNA-155 (miR-155) expression (p?50 21.8 and 22.3?μM at 48?h, respectively). Moreover, the levels of cytokines were suppressed by curcumin in miR-155 mimics transfected cells (p?p?p?Conclusions: Curcumin’s ability to suppress LPS-induced inflammatory response may be due to the inhibition of miR-155.     

2018-2022年深圳市妇幼保健院分离真菌的分布及耐药情况分析

目的 调查分析南方医科大学附属深圳妇幼保健院分离真菌的分布特点和药物敏感性情况,为妇幼真菌感染疾病的临床诊治、耐药性监测和流行病学研究提供参考。方法 回顾分析南方医科大学附属深圳妇幼保健院2018年1月-2022年12月标本采集、真菌鉴定和抗真菌药敏试验的结果数据。结果 共分离真菌3 350株,前2位分别为白色念珠菌1 542株、光滑念珠菌223株。阳性标本以阴道分泌物/宫颈分泌物为主。妇科和产科分离到的真菌最多。白色念珠菌对伊曲康唑、伏立康唑的5年耐药率分别为9.58%、4.12%,对两性霉素B和5-氟胞嘧啶的5年敏感率分别为99.79%、98.01%,对氟康唑的历年敏感率有逐渐升高的态势。光滑念珠菌、近平滑念珠菌和热带念珠菌对两性霉素B及5-氟胞嘧啶的敏感率均为100.00%。克柔念珠菌对两性霉素B和伏立康唑100.00%敏感。结论 南方医科大学附属深圳妇幼保健院分离真菌以念珠菌属为主,其中白色念珠菌最多。阴道分泌物/宫颈分泌物是主要真菌阳性分离标本。白色念珠菌对两性霉素B的耐药率最低、敏感率最高,对伊曲康唑的耐药率最高、敏感率最低。光滑念珠菌、近平滑念珠菌、热带念珠菌和克柔念珠菌对两性霉素B和5-氟胞嘧啶均无耐药性。光滑念珠菌对伊曲康唑耐药率最高、敏感率最低。     

Antiplasmodial activity of aqueous extract of Berberis aristata roots against Plasmodium berghei-infected BALB/c mice

Abstract

Context: The rising problem of resistance to present antimalarial drugs stresses the need to look for newer antiplasmodial components with effective modes of action. The roots of Berberis aristata DC. (Berberidaceae) are used in the traditional medicine for malaria in various parts of India.

Objective: The objective of this study was to evaluate antiplasmodial activity of B. aristata roots extract for the validation of its traditional medicinal use.

Material and methods: Aqueous root extract of Berberis aristata (AREBA) was screened for its in vitro as well as in vivo antiplasmodial activity against lethal rodent malaria parasite Plasmodium berghei NK65. In vitro activity was evaluated against schizont maturation of P. berghei using various concentrations ranging from 1 to 100?µg/mL. For in vivo studies, AREBA at the doses of 150, 250, 350, and 650?mg/kg/d was administered to P. berghei infected BALB/c mice orally for 4 consecutive days (D0–D3).

Results: AREBA showed in vitro antiplasmodial activity with an IC₅₀ value of 40?µg/mL. In vivo studies demonstrated a variable dose-dependent chemosuppression with higher efficacy at lower doses. At a dose of 350?mg/kg/d, the suppressive and preventive activities were found to be 67.1% and 53.9%, respectively, followed by enhancing mean survival period up to 12.8?d for the curative assay versus 7.5?d for the untreated mice.

Discussion and conclusion: These results provide relevant scientific evidences for the traditional medicinal use of this plant as malaria remedy and further advocates the isolation and characterization of active antiplasmodial principle from this plant.     

Locally Delivered Polyclonal Antibodies Potentiate Intravenous Antibiotic Efficacy Against Gram-Negative Infections

Purpose. Comparison of the anti-microbial efficacy of locally delivered antibodies in tandem with conventional systemic administration of ceftazidime antibiotic therapy in two lethal gram-negative animal infection models. Methods. Previously published lethal E. coli-induced closed peritonitis and Klebsiella-induced burn wound infections were generated in outbred female CF-1 mice cohorts. Pooled human polyclonal antibodies were injected locally into sites of infection in these mice simultaneously with intravenous infusions of the broad-spectrum antibiotic, ceftazidime. Mouse survival was compared in sham control cohorts vs. both ceftazidime-alone or antibody-alone systemically infused cohorts as well as local antibody-systemic ceftazidime combination therapy cohorts. Microbial burdens in blood and tissue samples (by agar plating), as well as interleukin-6 cytokine levels (using ELISA) correlated with sepsis, were monitored in sacrificed animals as a function of antimicrobial treatment regimen. Results. Local delivery of human polyclonal antibodies to infection sites was shown to produce synergistic therapeutic efficacy in combination with systemic antibiotic administration in these lethal wound infection models in mice. Enhanced benefits of the unique combination therapy included host survival, bacterial burden both locally and systemically, and IL-6 levels in host serum. Conclusions. Commercial pooled human antibodies contain a broad spectrum of antimicrobial activity against gram-negative pathogens. Prevention of systemization of infection correlates with host survival in these models. Local control of infection using doses of local, high-titer polyclonal antibodies can enhance traditional approaches to curb systemic spread of infection using intravenous antibiotics. Antibodies provide antimicrobial efficacy independent of known pathogen resistance mechanisms.