In silico and in vitro potentials of crocin and amphotericin B on Leishmania major: Multiple synergistic mechanisms of actions

A significant barrier to optimal antileishmanial treatment is low efficacy and the emergence of drug resistance. Multiple approaches were used to monitor and assess crocin (a central component of saffron) mixed with amphotericin B (AmpB) potential in silico and in vitro consequences. The binding behavior of crocin and iNOS was the purpose of molecular docking. The results showed that crocin coupled with AmpB demonstrated a safe combination, extremely antileishmanial, suppressed Leishmania arginase absorption, and increased parasite death. This natural flower component is a robust antioxidant, significantly promoting the expression of the Th1-connected cytokines (IL12p40, IFN-γ, and TNF- α), iNOS, and transcription factors (Elk-1, c-Fos, and STAT-1). In comparison, the expression of the Th2-associated phenotypes (IL-10, IL-4, and TGF-β) was significantly reduced. The leishmanicidal effect of this combination was also mediated through programmed cell death (PCD), as confirmed by the manifestation of phosphatidylserine and cell cycle detention at the sub-GO/G1 phase. In conclusion, crocin with AmpB synergistically exerted in vitro antileishmanial action, generated nitric oxide and reactive oxygen species, modulated Th1, and Th2 phenotypes and transfer factors, enhanced PCD profile and arrested the cell cycle of Leishmania major promastigotes. The main action of crocin and AmpB involved wide-ranging mechanistic insights for conducting other clinical settings as promising drug candidates for cutaneous leishmaniasis. Therefore, this combination could be esteemed as a basis for a potential bioactive component and a logical source for leishmanicidal drug development against CL in future advanced clinical settings.

Antileishmanial potentials of azacitidine and along with meglumine antimoniate on Leishmania major: In silico prediction and in vitro analysis

This study aimed to investigate the in vitro and in silico antileishmanial activity of azacitidine (AZA) on Leishmania major promastigotes and amastigotes. The in silico method was used to evaluate the possibility of the interaction of AZA into the binding pocket of inducible nitric oxide synthase (iNOS), a leading defensive oxidative metabolite. Following that, in vitro anti-promastigote, and anti-amastigote activity of AZA was determined using an MTT assay and a macrophage model, respectively. Cytotoxic effects of AZA and meglumine antimoniate (MA) were also assessed by MTT assay on murine macrophages. All experiments were performed in triplicate. The results showed that AZA interacted with Ser133, Gln134, and Lys13 amino acids of iNOS, and the molecular docking score was obtained at -241.053 kcal/mol. AZA in combination with MA significantly (P<0.001) inhibited the growth rate of nonclinical promastigote (IC50 247.6±7.3 μM) and 8.5-fold higher of clinical intramacrophage amastigote stage (29.8±5.3 μM), compared to the untreated group. A significant upsurge of Th1 subsets and transcription genes and a meaningful decline in Th2 cytokines subclasses at the equivalent concentrations of AZA and MA was observed (P<0.001). The apoptosis effect of AZA along with MA was significantly induced on L. major in a dose-dependent manner (P<0.001). The present study demonstrated that AZA possesses antileishmanial activity in in vitro and in silico models. However, AZA combined with MA was more effective than AZA alone in inhibiting the growth rate of promastigotes and amastigotes of L. major. This study indicates that AZA in combination with MA demonstrated a potent antileishmanial mechanism, promoting immune response and enhancing an immunomodulatory role toward the Th1 pathway. This experimental study is a basic study for applying more knowledge about the mechanisms of AZA along with MA in animal models in the future.

Synthesis and physicochemical characterization of Zn-Al layered double hydroxides (LDHs) as a delivery system for amphotericin B: In vitro and in silico antileishmanial study

Leishmaniasis as a widespread neglected vector-borne protozoan disease is a major public health concern in endemic areas due to 12 million people affected worldwide and 60,000 deaths annually. Several problems and side effects in using current chemotherapies leads to progression of new drug delivery systems against leishmaniasis. For instance, layered double hydroxides (LDHs) so-called anionic clays due to their proper characteristics, have been considered recently. In the present study, LDH nanocarriers were prepared using co-precipitation method. Then, the intercalation reactions with amphotericin B were conducted via indirect ion exchange assay. Finally, after characterization of prepared LDHs, the anti-leishmanial effects of Amp-Zn/Al-LDH nanocomposites against Leishmania major were evaluated using an in vitro and in silico model. According to results, current study demonstrated that Zn/Al-NO₃ LDH nanocarriers can be used as a new promising delivery system by intercalating amphotericin B into its interlayer space for leishmaniasis treatment by eliminating the L. major parasites by remarkable immunomodulatory, antioxidant and apoptotic effects.

The inhibitory effect of 6-gingerol and cisplatin on ovarian cancer and antitumor activity: In silico, in vitro, and in vivo

Background

Epithelial ovarian cancer is very common in women and causes hundreds of deaths per year worldwide. Chemotherapy drugs including cisplatin have adverse effects on patients' health. Complementary treatments and the use of herbal medicines can help improve the performance of medicine. 6-Gingerol is the major pharmacologically active component of ginger. In this study, we compared the effects of 6-gingerol, cisplatin, and their combination in apoptotic and angiogenetic activities in silico, in test tubes, and in in vivo assays against two ovarian cancer cell lines: OVCAR-3 and human umbilical vein endothelial cells (HUVECs).

Methods

The drug-treated cell lines were evaluated for their cytotoxicity, cell cycle, and apoptotic and angiogenetic gene expression changes.

Results

The proportion of apoptosis treated by 6-gingerol coupled with cisplatin was significantly high. In the evaluation of the cell cycle, the combination therapy also showed a significant promotion of a higher extent of the S sequence. The expression of p53 level, Caspase-8, Bax, and Apaf1 genes was amplified again with combination therapy. Conversely, in both cell lines, the cumulative drug concentrations reduced the expression of VEGF, FLT1, KDR, and Bcl-2 genes. Similarly, in the control group, combination treatment significantly decreased the expression of VEGF, FLT1, KDR, and Bcl-2 genes in comparison to cisplatin alone.

Conclusions

The findings of the present study demonstrated that the cisplatin and 6-gingerol combination is more effective in inducing apoptosis and suppressing the angiogenesis of ovarian cancer cells than using each drug alone.

Empagliflozin induces apoptotic-signaling pathway in embryonic vasculature: In vivo and in silico approaches via chick’s yolk sac membrane model

The present investigation was conducted to evaluate the vascular-toxicity of empagliflozin (EMP) in embryonic vasculature. Firstly, the vascular-toxicity of the drug as well as its interaction with apoptotic regulator proteins was predicted via in silico approach. In the next step, the apoptotic-signaling pathway in embryonic vasculature was evaluated using a chick’s YSM model. In silico simulation confirmed vascular-toxicity of EMP. There was also an accurate affinity between EMP, Bax and Bcl-2 (−7.9 kcal/mol). Molecular dynamics assay revealed complex stability in the human body conditions. Furthermore, EMP is suggested to alter Bcl-2 more than BAX. Morphometric quantification of the vessels showed that the apoptotic activity of EMP in embryonic vasculature was related to a marked reduction in vessel area, vessel diameter and mean capillary area. Based on the qPCR and immunohistochemistry assays, enhanced expression level of BAX and reduced expression level of Bcl-2 confirmed apoptotic responses in the vessels of the YSM. We observed that induction of an apoptotic signal can cause the embryonic defect of the vascular system following EMP treatment. The acquired data also raised suspicions that alteration in apoptotic genes and proteins in the vasculature are two critical pathways in vascular-toxicity of EMP.

Effects of Moderate-Intensity Interval Training on Gene Expression and Antioxidant Status in the Hippocampus of Methamphetamine-Dependent Rats

Methamphetamine (METH) can cause neurotoxicity and increase the risk of neurodegenerative disorders such as Alzheimer's and Parkinson's diseases. This study aimed to investigate the effect of moderate-intensity interval training (MIIT) on gene expression and antioxidant status of the hippocampus of METH-dependent rats. Thirty-two male Wistar rats were randomly divided into four equal groups (n = 8): saline, METH, MIIT, and METH + MIIT. METH was injected intraperitoneally at 5 mg/kg for 21 days. The MIIT(interval running) was performed on the treadmill 5 days a week for 8 weeks. Morris water maze test was performed to measure learning and memory. Then, the hippocampal tissue was extracted to evaluate changes in gene expression and biochemical enzymes. The data were analyzed using one-way and two-way ANOVA methods at p < 0.05. The results showed that METH injection significantly reduced spatial memory and antioxidant enzymes and increased the expression of α-synuclein (α-syn), cyclin-dependent kinase 5 (CDK5), tau, and phosphorylated tau (p-tau) genes compared to the saline group. MIIT significantly increased spatial memory and antioxidant enzymes. However, it reduced α-syn, CDK5, tau, and p-tau expression. Thus, this study depicted that methamphetamine-dependent rats with memory deficits have lower antioxidant enzyme levels and higher expression of α-syn, CDK5, tau, and p-tau genes, and that an 8-week MIIT may have beneficial effects on the memory impairments as well as antioxidant status and gene expression in male rats.

Cytotoxicity of Amphotericin B and AmBisome: In Silico and In Vivo Evaluation Employing the Chick Embryo Model

Leishmaniasis has been identified as a significant disease in tropical and subtropical regions of the world, with Iran being one of the disease-endemic areas. Various treatments have been applied for this disease, and amphotericin B (Amp B) is the second line of treatment. Side effects of this drug have been reported in various organs. The present study investigated the effects of different types of Amp B on fetal organs using in silico and in vivo assays (chicken embryos). In vivo analysis was done by checking pathological changes, angiogenesis, and apoptosis alterations on eggs treated by Amp B and AmBisome. In silico approach was employed to predict the affinity of Amp B and AmBisome to the vascular endothelial growth factor A (VEGF-A), its receptor (KDR1), apoptotic-regulator proteins (Bcl-2-associated X protein (Bax), B-cell lymphoma (Bcl-2), and Caspase-8. The ADME-toxicity prediction reveals that AmBisome possesses a superior pharmacological effect to Amp B. The best result of all the dockings in the Molegro Virtual Docker (MVD) was obtained between Bax, Bcl-2, Caspase-8, KDR1, and VEGF-A targets. Due to the lower Egap (HOMO–LUMO) of AmBisome, the chemical reactivity of AmBisome was higher than that of Amp B. In vivo analysis showed that embryos that received Amp B exhibited less vascular density than AmBisome. Amp B alone significantly increased the expression of apoptosis and decreased angiogenesis genes compared to AmBisome. The histopathology analysis of the treated embryos showed a reduction in the blood vessel collapse and an increase in degenerative and apoptotic–necrotic changes in the embryonic tissues. Overall, the results suggest the potential benefits of AmBisome over Amp B, which might be a better treatment strategy to treat leishmaniasis during pregnancy.

Antiproliferative properties of Turmerone on Leishmania major: Modes of action confirmed by antioxidative and immunomodulatory roles

Treatment of leishmaniasis by conventional synthetic compounds has faced a serious challenge worldwide. This study was performed to evaluate the effect and modes of action of aromatic Turmerone on the Leishmania major intra-macrophage amastigotes, the causative agent of zoonotic cutaneous leishmaniasis in the Old World. In the findings, the mean numbers of L. major amastigotes in macrophages were significantly decreased in exposure to Turmerone plus meglumine antimoniate (Glucantime®; MA) than MA alone, especially at 50 µg/mL. In addition, Turmerone demonstrated no cytotoxicity as the selectivity index (SI) was 21.1; while it induced significant apoptosis in a dose-dependent manner on L. major promastigotes. In silico molecular docking analyses indicated an affinity of Turmerone to IL-12, with the MolDock score of - 96.8 kcal/mol; which may explain the increased levels of Th1 cytokines and decreased level of IL-10. The main mechanism of action is more likely associated with stimulating a powerful antioxidant and promoting the immunomodulatory roles in the killing of the target organism.

In vitro and in vivo therapeutic potentials of 6-gingerol in combination with amphotericin B for treatment of Leishmania major infection: Powerful synergistic and multifunctional effects

The ongoing conventional drugs for leishmaniasis treatment are insufficient. The present study aimed to assess 6-gingerol alone and in combination with amphotericin B on Leishmania major stages using experimental and in vivo murine models. Here, arrays of experimental approaches were designed to monitor and evaluate the 6-gingerol potential therapeutic outcomes. The binding affinity of 6-gingerol and IFN-γ was the basis for docking conformations. 6-Gingerol combined with amphotericin B represented a safe mixture, extremely leishmanicidal, a potent antioxidant, induced a remarkable apoptotic index, significantly increased the expression of the Th1-related cytokines (IL-12p40, IFN-γ, and TNF- α), iNOS, and transcription factors (STAT1, c-Fos, and Elk-1). In contrast, the expression of the Th2-related cytokines was significantly downregulated (p < 0.001). This combination was also potent when the lesion appearance was evaluated following three weeks of treatment. The histopathological and immunohistochemical patterns of the murine model represented clusters of CD4+ and CD8+ T lymphocytes which compressed and deteriorated the macrophages harboring Leishman bodies. The primary mode of action of 6-gingerol and amphotericin B involved broad mechanistic insights providing a coherent basis for further clinical study as a potential drug candidate for CL. In conclusion, 6-gingerol with amphotericin B synergistically exerted anti-leishmanial activity in vitro and in vivo and potentiated macrophages' leishmanicidal activity, modulated Th1- and Th2-related phenotypes improved the histopathological changes in the BALB/c mice infected with L. major. They elevated the leukocyte infiltration into the lesions. Therefore, this combination should be considered for treating volunteer patients with CL in clinical studies.

Leishmanicidal, cytotoxic and apoptotic effects of Gossypium hirsutum bulb extract and its separated fractions on Leishmania major

BACKGROUND & OBJECTIVES

Leishmaniasis is a major global health problem with no safe and effective therapeutic drugs. This study evaluated the cytotoxic and apoptotic effects of crude extract and fractions of Gossypium hirsutum bulb on Leishmania major stages using advanced experimental models.

METHODS

Bulbs of G. hirsutum were collected from the Kerman province of Iran. The bulb was extracted using Soxhlet apparatus and different fractions were obtained by column chromatography (CC). Different concentrations of the extract and the fractions were evaluated against L. major and compared with Glucantime®. The cytotoxicity and apoptotic values were analysed by flow cytometry. The fractions obtained in CC were monitored by thin layer chromatography, and fractions with similar chromatographic patterns were mixed.

RESULTS

The extract and two fractions, F4 and F5 inhibited the proliferation of L. major promastigotes and amastigotes in a dose-dependent manner at 72 h post-treatment. No significant cytotoxic effects were observed for extract and fractions, as the selectivity index was over 1000, far beyond >10. The mean apoptotic values for L. major were superior to those of Glucantime^®.

INTERPRETATION & CONCLUSION

Both the crude extract and fractions (F4 and F5) had significant antileishmanial effects on L. major stages, and were were superior relative to Glucantime^®. No cytotoxic effects were associated with the extract or fractions and they showed excellent apoptotic index, a possible mechanism behind inducing parasite death. Further investigations are essential to study the effect of G. hirsutum bulb fractions in animal model and clinical settings for planning strategies for the prevention and control of leishmaniasis.

Clinical and laboratory evaluation of cured and non-cured patients with cutaneous leishmaniasis treated by Glucantime

BACKGROUND & OBJECTIVES

Insufficient treatment of cutaneous leishmaniasis (CL) by conventional drugs is a major barrier in control strategies. This study was aimed to evaluate Glucantime efficacy and the susceptibility of Glucantime unresponsive and responsive CL isolates in the field and laboratory.

METHODS

Chi-square test (x^[2]) was used to determine the significance of difference between proportions in Glucantime-treated patients. The inhibitory activity of various concentrations of Glucantime against Leishmenia tropica stages was evaluated by a colorimetric cell viability MTT and macrophage assays. Mixed model, t-test and ANOVA were performed to determine the significance of difference between various concentrations of Glucantime unresponsive or responsive isolates and untreated control group and p <0.05 was defined as significant level. Altogether, 89.8% of the patients were cured by Glucantime, whilst 10.2% remained non-cured.

RESULTS

The overall Glucantime efficacy in different age groups and genders was similar. The IC₅₀ values of promastigotes and amastigotes for Glucanime unresponsive isolates were 2.1 and 2.6 times higher than the equivalent rates obtained for responsive cases, respectively. The overall mean number of amastigotes within macrophages in unresponsive isolates was significantly higher (32.68 ± 1.24) than that in responsive ones (18.68 ± 1.52, p <0.001). Glucantime unresponsive and responsive field isolates of anthroponotic CL (ACL) caused by L. tropica strongly correlated to in vitro assays.

INTERPRETATION & CONCLUSION

Monitoring of Glucantime unresponsiveness by the health surveillance system is extremely important, where anthroponotic transmission occurs in humans. Hence, physicians should be aware of such clinical unresponsive presentations with ACL for antimonial therapeutic failure to improve management of disease in endemic regions.

Partridge and embryonated partridge egg as new preclinical models for candidiasis

Candida albicans (C. albicans) is the most common cause of candidiasis in humans and animals. This study was established to a new experimental infection model for systemic candidiasis using partridge and embryonated partridge egg. First, we tested the induction of systemic candidiasis in partridge and embryonated partridge egg. Finally, interaction between virulence factors of C. albicans and Bcl-2 family members was predicted. We observed that embryonic infection causes a decrease in survival time and at later embryonic days (11–12th), embryos showed lesions. Morphometric analysis of the extra-embryonic membrane (EEM) vasculature showed that vascular apoptotic effect of C. albicans was revealed by a significant reduction in capillary area. In immunohistochemistry assay, low expression of Bcl-2 and increased expression of Bax confirmed apoptosis. The gene expression of Bax and Bcl-2 was also altered in fungi-exposed EEM. Ourin silico simulation has shown an accurate interaction between aspartic proteinase, polyamine oxidase, Bcl-2 and BAX. We observed that the disease was associated with adverse consequences, which were similar to human candidiasis. Acquired results support the idea that partridge and embryonated partridge egg can be utilized as appropriate preclinical models to investigate the pathological effects of candidiasis.

The potential role and apoptotic profile of three medicinal plant extracts on Leishmania tropica by MTT assay, macrophage model and flow cytometry analysis

Introduction

Treatment of leishmaniasis with conventional synthetic drugs is a major global challenge. This study was designed to explore the leishmanicidal activity and apoptotic profile of three leaf extracts on Leishmania tropica stages.

Methods

The plants of Quercus velutina, Calotropis procera and Nicotiana tabacum were gathered from Anbarabbad county, in the southeastern part of Kerman province and extracted by maceration method using methanol alcohol. Various concentrations of the extracts (1, 10, 100 and 1000 μg/mL) were used against L. tropica stages to evaluate the inhibitory effect by colorimetric assay, macrophage model and flow cytometry. The MTT assay was conducted to determine the IC₅₀ and CC₅₀ values in promastigotes and J774-A1 macrophages, respectively. For intra-macrophage amastigotes, the leishmanicidal activity was evaluated by calculating the mean number of amastigotes in each macrophage and also IC₅₀ values. The promastigote or amastigote stages with no drug and complete medium without organisms were considered as positive and negative controls, respectively. Meglumine antimoniate (Glucantime) was also used as standard drug. Also, annexin V was used to assess the apoptotic profile. All treatment settings were incubated for a standard time of 72 h in triplicates. Data were analyzed by t-test and ANOVA.

Results

The findings showed that all plant extracts inhibited the proliferation rate of promastigotes and amastigotes (P ˂ 0.001); especially, Q. velutina represented the lowest IC₅₀ in both stages. Besides, Q. velutina showed the least number of amastigotes in each macrophage compared to the other groups (4.5 μg/mL). The percentage of parasitic apoptosis at 1000 μg/mL of Q. velutina, C. procera, N. tabacum and Glucantime® were 37.4, 18.6, 8.5 and 52.4, respectively. Amastigotes (clinical stage) were significantly more susceptible to extracts and also Glucantime® than promastigotes (P < 0.001).

Conclusions

This study revealed that all three extracts of Q. velutina, C. procera and N. tabacum exhibited an effective antileishmanial activity and induced apoptosis against the L. tropica promastigotes. Further investigations are essential to isolate and analyze the chemical compositions and their biological properties.

The potential role of nicotinamide on Leishmania tropica: An assessment of inhibitory effect, cytokines gene expression and arginase profiling

Leishmaniasis represents a major health concern worldwide which has no effective treatment modality. Nicotinamide (NAm) has been used for a wide range of applications from anticancer to antimicrobial usage. This study aimed to assess the effect of NAm combination on Leishmania tropica Inhibition, as well as on cytokines gene expression and arginase (ARG) activity in L. tropica-infected macrophages in an in vitro model. The leishmanicidal effects of NAm and Glucantime (meglumine antimoniate, MA) alone and in combination (NAm/MA) were evaluated using a colorimetric assay and macrophage model. Additionally, immunomodulatory effects and enzymatic activity were assessed by analyzing Th1 and Th2 cytokines gene expression and ARG level, respectively, in infected macrophages treated with NAm and MA, alone and in combination. Findings indicated that the NAm/MA combination demonstrated greater inhibitory effects on L. tropica promastigotes and amastigotes compared with each drug individually. Docking results proved the affinity of NAm to IFN-γ, which can affirm the increased levels of IFN-γ, IL-12p40 and TNF-α as well as reductions in IL-10 secretion with a dose-response effect, especially in the combination group. The NAm/MA combination also showed a significant reduction in the level of ARG activity at all concentrations used compared to each drug individually. These findings indicate higher effectiveness of NAm plus MA in reducing parasite growth, promoting immune response and inhibiting ARG level. This combination should be considered as a potential therapeutic regimen for treatment of volunteer patients with anthroponotic cutaneous leishmaniasis (ACL) in future control programs.

Epidemiological and molecular studies on Echinococcus granulosus from free-roaming dogs in Southeast Iran

Background and Aim:

Cystic echinococcosis (CE), as a major zoonotic helminth infection, imposes remarkable socioeconomic burden on many endemic countries across the world, including Iran. Due to the high importance of free-roaming dogs in the transmission of CE, epidemiological and molecular studies in this type of hosts are required in the endemic regions. This study aimed to investigate the epidemiology and genotyping of Echinococcusgranulosus isolated from stray dogs in Kerman, Southeast Iran.

Materials and Methods:

Eighty-four samples were isolated from stray dogs in the city and suburbs of Kerman in coordination with the health authorities and the municipality office for rabies control and dog population management. Dog demographic data, including age and sex were collected. The worm was isolated by necropsy and genomic DNA was extracted and partial cytochrome c oxidase subunit 1 gene was amplified using specific primers. Phylogenetic and Templeton-Crandall-Sing (TCS) network analyses were carried out on the sequence data.

Results:

The overall prevalence of CE in the surveyed dogs was 10.7% (9/84 cases). Out of 84 stray dogs, 33 (39.3%) and 51 (60.7%) cases were male and female, respectively. There was not a statistically significant difference between the infection and gender of dogs. However, infection is shown more in dogs under one year of age with a statistically significant difference (p<0.05). The results of molecular studies indicated E. granulosus G1 genotype for all isolates. The high presence of free-roaming dogs in urban and peri-urban areas and high frequency of parasite in this animal is a risk factor for humans in the region. Haplotype sequence analysis on the dog isolates revealed a close relationship with other E. granulosus isolates in Kerman.

Conclusion:

The findings of this study provide evidence-based data about the epidemiological and molecular characteristics of CE in dog definitive hosts of Southeast Iran. Further studies are required to understand the prevalence and parasite genotypes in dogs in Iran.

Calcium carbonate nanowires: greener biosynthesis and their leishmanicidal activity

The synthesis of inorganic rod shape nanostructures is important in chromatography, dentistry, and medical applications such as bone implants, and drug and gene delivery systems.

Niosomal formulation of amphotericin B alone and in combination with glucantime: In vitro and in vivo leishmanicidal effects

This study aimed to evaluate the efficacy of glucantime and amphotericin B (AmB) encapsulated in niosome against cutaneous leishmaniasis (CL) using in vitro and in vivo models. The niosomal formulations of the drugs alone and in combination were prepared and characterized. Subsequent to the examination of their cytotoxicity, their efficacy was evaluated using an in vitro MTT assay, macrophage model, flow cytometry, and gene expression profiling. For evaluation of therapeutic effect of niosomal combination on the lesion induced by Leishmania major in inbred BALB/c mice, the size of lesions and number of parasites in spleen was assessed. The niosomal formulations demonstrated significantly greater inhibitory effects compared with the non-niosomal forms when the IC₅₀ was considered. The niosomal combination showed an increase in the apoptotic values and gene expression levels of IL-12 and metacaspase and a decrease in the levels of IL-10 with a dose-response effect. The niosomal combination was also effective in reducing the lesion size and splenic parasite burden in mice. Our findings indicated that there is a synergistic effect between AmB and glucantime in niosomal form in the inhibition of intracellular and extracellular forms of L. tropica. Additionally, the in vivo results on L. major suggest that topical niosomal formulation could be useful in the treatment of CL.

A Novel Niosomal Combination of Selenium Coupled with Glucantime against Leishmania tropica

There is no effective treatment modality available against different forms of leishmaniasis. Therefore, the aim of this study was to improve the penetration and efficacy of selenium and glucantime coupled with niosomes and compared them with their simple forms alone on in vitro susceptibility assays. In this study, the niosomal formulations of selenium and in combination with glucantime were prepared. The size and morphology of the niosomal formulations were characterized and the effectivity of the new formulation was also evaluated using in vitro MTT assay, intra-macrophage model, and gene expression profile. From the results obtained, no cytotoxicity effect was observed for niosomal and simple forms of drugs, as alone or in combination. Niosomal formulations of the drugs significantly showed more inhibitory effects (P ≤ 0.001) than the simple drugs when the selectivity index was considered. The gene expression levels of Interleukin (IL-10) significantly decreased, while the level of IL-12 and metacaspase significantly increased (P ≤ 0.001). The results of the present study showed that selenium plus glucantime niosome possess a potent anti-leishmanial effect and enhanced their lethal activity as evidenced by the in vitro experiments.

Host's immune response in unresponsive and responsive patients with anthroponotic cutaneous leishmaniasis treated by meglumine antimoniate: A case-control study of Th1 and Th2 pathways

The objective of the present study was to compare the host's immune responses between unresponsive and responsive patients with anthroponotic cutaneous leishmaniasis (ACL) treated by meglumine antimoniate. A case-control study was carried out in an endemic focus in Iran. Blood samples were taken from patients and peripheral blood mononuclear cells (PBMCs) were isolated. Two wells were considered for each isolate of unresponsive and responsive patients; one was exposed to L. tropica (Lt-stimulated cells) and the other remained non-exposed (non-stimulated cells). After 24 h of incubation, whole RNA was extracted from each sample. Real-time quantitative PCR was carried out to confirm the differences in expression levels of IL-12 P40, IFN-γ, IL-1β, IL-4 and IL-10 among isolates. Data were analyzed and P < 0.05 was considered to be statistically significant. In our study, Lt-stimulated cells and non-stimulated cells in unresponsive groups demonstrated significantly lower expression levels of IL-1β, IL-12 P40 and IFN-γ genes and higher expression levels of IL-4 and IL-10 genes, compared to Lt-stimulated cells and non-stimulated cells in responsive groups. There was a negative correlation between IL-12 P40 with IL-10 and IL-1β with IL-10 in ACL Lt-stimulated cells in unresponsive group, while a positive correlation between IL-12 P40 with IL-1β and IL-12 P40 with IFN-γ in ACL Lt-stimulated cells in responsive group. Probably, different immune responses caused by various factors play a major role in the pathogenesis and development of unresponsiveness in ACL patients. The profile and timing of cytokine production correlated well with the treatment outcome of Leishmania infection.

Differential expression of TLRs 2, 4, 9, iNOS and TNF-α and arginase activity in peripheral blood monocytes from glucantime unresponsive and responsive patients with anthroponotic cutaneous leishmaniasis caused by Leishmania tropica

BACKGROUND

Detection of the mechanism of host/parasite interactions in unresponsive forms of anthroponotic cutaneous leishmaniasis (ACL) caused by Leishmania tropica is helpful for immunotherapy and vaccine development. In the present study, the gene expression of toll-like receptors (TLRs), TNF-α, iNOS and also arginase (ARG) activity in monocytes from Glucantime unresponsive in comparison to responsive patients infected with L. tropica was investigated.

METHODS

In this case-control study, patients with unresponsive (n = 10) and responsive (n = 10) ACL were recruited. Gene expression of TLR2, TLR4, TLR9, TNF-α and iNOS was analyzed in L. tropica-exposed monocytes. The level of ARG activity in both isolated promastigotes and the lysates of monocytes was also determined.

RESULTS

L. tropica-exposed monocytes represented higher expression of all three TLRs and TNF-α and lower expression of iNOS compared to unexposed ones in both groups of patients. Results revealed a significant down-regulation of TLR2 and TNF-α and up-regulation of TLR9 expression in unresponsive isolates in comparison to responsive ones. Besides, ARG level showed a significant increase in L. tropica-stimulated monocytes and cultured promastigotes from unresponsive isolates versus responsive ones.

CONCLUSIONS

The decreased TLR2, TLR4, TNF-α and iNOS and the increased level of TLR9 expression in L. tropica-exposed monocytes from unresponsive isolates and also the increment in ARG activity in their promastigotes and monocytes, might possibly be involved in the severity of the disease and leading to Glucantime unresponsiveness.

Cryotherapy of cutaneous leishmaniasis caused by Leishmania major in BALB/c mice: A comparative experimental study

Background & objectives

Leishmania parasites are sensitive to very low temperature. Cryotherapy is considered as an alternative to the existing pentavalent antimonials, for local treatment of cutaneous leishmaniasis (CL). Normally, liquid nitrogen (N₂) at a temperature of -196 °C, is used in cryotherapy of CL, but it's efficacy is not consistent. Recently, few studies have also reported the use of carbon dioxide (CO₂) slush at -78.5 °C in CL cryotherapy. This study was aimed to evaluate the effectiveness of N₂ vs CO₂ cryotherapy for CL treatment in mice. Methods: In total, 21 BALB/c mice were infected with Leishmania major strain [MRHO/IR/74/ER]. Samples were divided into three groups based on the intervention provided-Solid CO₂ cryotherapy, liquid N₂ cryotherapy and control group; with seven mice randomly assigned to each group. Control group received no intervention, and in the other two groups cryotherapy was used every two weeks for maximum of three months. Follow up examinations were scheduled at the time of cryotherapy, during which the size of each lesion was measured. For three mice in each study group, the spleen parasite DNA load was quantified using real-time PCR.

Results

After treatment, the liquid N₂ cryotherapy showed significant reduction in size of the lesions (p = 0.029) as compared to the solid CO₂ cryotherapy and control group. Also, Leishmania DNA load in spleen was significantly lower in the mice receiving liquid N₂ cryotherapy (p <0.001).

Interpretation & conclusion

Liquid N₂ cryotherapy is superior to CO₂ cryotherapy, and it can be an effective method for controlling L. major infection. Further investigations are essential to find optimal number of treatment sessions and time intervals.

Geographical distribution and molecular characterization for cutaneous leishmaniasis species by sequencing and phylogenetic analyses of kDNA and ITS1 loci markers in south-eastern Iran

This study aimed to explore geographic distribution and molecular characterization of cutaneous leishmaniasis (CL) species by amplifying two popular markers in kinetoplast DNA and internal transcribed spacer 1 loci by nested-PCR, and characterized by sequencing and phylogenetic analyses. Findings demonstrated that two species co-existed in the province: L. tropica (88.5%) and L. major (11.5%). All gender and age groups were equally infected, although males, 21-30 years old, exhibited a significantly higher infection. Sequencing and phylogenetic analyses of 34 randomly selected samples showed that L. tropica isolates exhibited some degree of heterogeneity. Both anthroponotic CL and zoonotic CL are present in south-eastern Iran with predominance of L. tropica species. Some level of heterogeneity was observed in L. tropica isolates which possibly reflects different colonies in the area. Implementation of diagnostic tools directly from clinical samples could be an important strategic approach for exploration of spatial distribution, molecular characterization and phylogenetic analyses.

Molecular detection and genetic diversity of Toxoplasma gondii in different tissues of sheep and goat in Eastern Iran

This study was designed to detect parasitic DNA in tissues from sheep and goats raised and slaughtered in the southeastern Iran as well as to genetically characterize infecting strains of T. gondii. A total of 240 tissue samples consisting of heart, brain, and diaphragm were obtained from sheep (n=40) and goats (n=40) slaughtered in abattoirs from three provinces located in southeastern Iran including Kerman, Razavi Khorasan, and South Khorasan Provinces between February to October 2015. Nested PCR amplified the B1 and GRA6 genes. To determine the genetic characterization of positive samples, all genotyped positive samples were examined by PCR-RFLP. Sequencing analysis was performed to evaluate the prevalence of type strains (I, II and III). A total of 68(56.66%) tissue samples of sheep and 53(44.16%) from goats were found to be positive for T. gondii B1 gene, that included 11(27.5%) diaphragm, 21(52.5%) heart, and 36(90%) brain of sheep; and 20(50%) diaphragm, 11(22%) heart and 22(55%) brain of goats. Moreover, 22(18.3%) tissue samples of sheep and 20(16.6%) tissue samples of goats were found positive with GRA6 gene for T. gondii. There are three genotypes and mix genotype using mseI enzyme among all positive samples. The results demonstrated the presence of T. gondii DNA in tissues of sheep and goats from southeast of Iran. Control of Toxoplasma infection animal products are important in consumer protection.

Life cycle energy use, costs, and greenhouse gas emission of broiler farms in different production systems in Iran-a case study of Alborz province

In order to achieve sustainable development in agriculture, it is necessary to quantify and compare the energy, economic, and environmental aspects of products. This paper studied the energy, economic, and greenhouse gas (GHG) emission patterns in broiler chicken farms in the Alborz province of Iran. We studied the effect of the broiler farm size as different production systems on the energy, economic, and environmental indices. Energy use efficiency (EUE) and benefit-cost ratio (BCR) were 0.16 and 1.11, respectively. Diesel fuel and feed contributed the most in total energy inputs, while feed and chicks were the most important inputs in economic analysis. GHG emission calculations showed that production of 1000 birds produces 19.13 t CO_2-eq and feed had the highest share in total GHG emission. Total GHG emissions based on different functional units were 8.5 t CO_2-eq per t of carcass and 6.83 kg CO_2-eq per kg live weight. Results of farm size effect on EUE revealed that large farms had better energy management. For BCR, there was no significant difference between farms. Lower total GHG emissions were reported for large farms, caused by better management of inputs and fewer bird losses. Large farms with more investment had more efficient equipment, resulting in a decrease of the input consumption. In view of our study, it is recommended to support the small-scale broiler industry by providing subsidies to promote the use of high-efficiency equipment. To decrease the amount of energy usage and GHG emissions, replacing heaters (which use diesel fuel) with natural gas heaters can be considered. In addition to the above recommendations, the use of energy saving light bulbs may reduce broiler farm electricity consumption.

Human polymorphonuclear leukocytes produce cytokines in response to Leishmania major promastigotes

Polymorphonuclear leukocytes (PMN) release cytokines that may influence the development of the subsequent adaptive immune response. Little is known about cytokines produced by human PMN in response to Leishmania (L.). In this study, mRNA expression of Interleukin (IL)-12p40, IL-12p35, Interferon (IFN)-γ, transforming growth factor (TGF)-β, IL-1, and IL-4 in PMN of volunteers stimulated with L. major promastigotes has been investigated by real-time PCR and the results were confirmed by flow cytometer. The results showed that L. major did not induce mRNA expression of IL12p40, IL12p35, IFN-γ, and TGF-β in PMN, while IL-1 and IL-4 mRNA were induced. Flow cytometry results confirmed no IFN-γ production by PMN with or without stimulation. IL-12p70 was present in untreated and L. major-treated PMN, and these cells release IL-12 following incubation with L. major. Significant amount of IL-1 even without treatment with promastigotes was detected in PMN. Moreover, the proportion of PMN, which produce IL-1 in response to L. major, was increased compared with the percent of unstimulated IL-1-producing PMN. The results showed the accumulation of small amounts of IL-4 in PMN after stimulation. In conclusion, our results indicate that IL-12 and IL-1 are pre-stored in human PMN, nor L. major induces IL-1 and IL-4, but not IL-12, IFN-γ, nor TGF-β expression in these cells.

Modeling of Basil Leaves Drying by GA–ANN

In this research, the experiment is done by a dryer. It could provide any desired drying air temperature between 20 and 120°C and air relative humidity between 5 and 95% and air velocity between 0.1 and 5.0 m/s with high accuracy, and the drying experiment was conducted at five air temperatures of 40, 50, 60, 70 and 80°C and at three relative humidity 20, 40 and 60% and air velocity of 1.5, 2 and 2.5 m/s to dry Basil leaves. Then with developed Program in MATLAB software and by Genetic Algorithm could find the best Feed-Forward Neural Network (FFNN) structure to model the moisture content of dried Basil in each condition; anyway the result of best network by GA had only one hidden layer with 11 neurons. This network could predict moisture content of dried basil leaves with correlation coefficient of 0.99.

Hybrid response surface methodology-genetic algorithm optimization of ultrasound-assisted transesterification of waste oil catalysed by immobilized lipase on mesoporous silica/iron oxide magnetic core-shell nanoparticles

The production ofbiodiesel by transesterification of waste cooking oil (WCO) to partially substitute petroleum diesel is one of the measures for solving the twin problems of environment pollution and energy demand. An environmentally benign process for the enzymatic transesterification using immobilized lipase has attracted considerable attention for biodiesel production. Here, a superparamagnetic, high surface area substrate for lipase immobilization is evaluated. These immobilization substrates are composed of mesoporous silica/superparamagnetic iron oxide core-shell nanoparticles. The effects of methanol ratio to WCO, lipase concentration, water content and reaction time on the synthesis of biodiesel were analysed by utilizing the response surface methodology (RSM). A quadratic response surface equation for calculating fatty acid methyl ester (FAME) content as the objective function was established based on experimental data obtained in accordance with the central composite design. The RSM-based model was then used as the fitness function for genetic algorithm (GA) to optimize its input space. Hybrid RSM-GA predicted the maximum FAME content (91%) at the optimum level of medium variables: methanol ratio to WCO, 4.34; lipase content, 43.6%; water content, 10.22%; and reaction time, 6h. Moreover, the immobilized lipase could be used for four times without considerable loss of the activity.

Carbohydrate and amino acid degradation pathways in L-methionine/D-[13C] glucose model systems

Maillard model systems consisting of labeled D-[(13)C]glucoses, L-[(15)N]methionine, and L-[methyl-(13)C]methionine, have been utilized to identify the amino acid and carbohydrate fragmentation pathways occurring in the model system through Py-GC/MS analysis. The label incorporation analyses have indicated that the carbohydrate moiety produces 1-deoxy- and 3-deoxyglucosones and undergoes C(2)/C(4) and C(3)/C(3) cleavages to produce glycolaldehyde, tetrose, and C(3)-reactive sugar derivatives such as acetol, glyceraldehyde, and pyruvaldehyde. Glycolaldehyde was found to incorporate C-1, C-2 (70%) and C-5, C-6 (30%) glucose carbon fragments, whereas the tetrose moiety incorporates only C-3, C-4, C-5, C-6 glucose carbon atoms. In addition, the major source of reactive C(3) fragments was found to contain C-4, C-5, C-6 sugar moiety. On the other hand, methionine alone also generated Strecker aldehyde as detected by its condensation product with 3-(methylthio)propylamine. Plausible mechanisms were proposed for the formation of the interaction products between sugar and amino acid degradation products on the basis of the label incorporation patterns.

Origin of carbohydrate degradation products in L-Alanine/D-[(13)C]glucose model systems

Maillard model systems consisting of labeled D-[(13)C]glucoses and L-[(13)C]alanines have been utilized to identify the origin of carbon atoms in glycolaldehyde, pyruvaldehyde, 1-hydroxy-2-propanone (acetol), 2,3-butanedione, 3-hydroxy-2-butanone, 2,3-pentanedione, and compounds containing C(5) and C(6) intact glucose carbon chains. The origin of carbon atoms in glycolaldehyde and pyruvaldehyde was inferred from the analysis of label incorporation pattern of methyl and dimethylpyrazines. The origin of carbon atoms in the remaining compounds was determined by direct analysis. The data indicated that glycolaldehyde incorporated intact C5-C6 and C1-C2 carbon chains of glucose. Acetol and pyruvaldehyde incorporated intact C1-C2-C3 and C4-C5-C6 carbon chains of glucose. On the other hand, 2, 3-butanedione and 3-hydroxy-2-butanone incorporated intact C3-C4-C5-C6 carbon chain of glucose. In addition, analysis of compounds containing intact glucose C(5) carbon chains have indicated that glucose in the presence of L-alanine can lose either C-1 atom to produce a pentitol moiety responsible for the formation of furanmethanol or it can lose the C-6 atom to produce a pentose moiety responsible for the formation of furfural. Plausible mechanisms, consistent with the observed label incorporation, were proposed for the formation of sugar degradation products.

Formation of sugar-specific reactive intermediates from (13)C-labeled L-serines

Analysis of the pyrolysis products of [1-(13)C], [2-(13)C], and [3-(13)C]-labeled L-serines has indicated the presence of three initial degradation pathways. Decarboxylation followed by deamination produces aminoethanol and acetaldehyde, respectively; a retro-aldol pathway generates formaldehyde and glycine. Dehydration of L-serine can lead to the formation of pyruvic acid, which eventually can be converted into the amino acid alanine. Formation of alanine and glycine was confirmed due to the detection of 2, 5-diketo-3,6-dimethylpiperazine and cycloglycylalanine. Most of the advanced decomposition products of L-serine can be rationalized on the basis of these initial degradation products. Label incorporation studies have elucidated the origin of carbonyl precursors of methyl- and 2,3-dimethylpyrazines formed in the thermal decomposition mixture of L-serine. Three mechanistic pathways were identified for the formation of carbonyl precursors of methyl- and 2, 3-dimethylpyrazines. The major pathway (70%) for the formation of the precursor of methylpyrazine involved aldol addition of formaldehyde to glycolaldehyde to form glyceraldehyde. On the other hand, the major pathway (60%) for the formation of the precursor of 2,3-dimethylpyrazine involved an aldol condensation of acetaldehyde with glycolaldehyde to form 2,3-butanedione.

Increased CD38 expression is associated with favorable prognosis in adult acute leukemia

CD38 is expressed in acute lymphoblastic leukemia (ALL) and acute myelogenous leukemia (AML) blasts and its prognostic significance is unknown. We investigated CD38 expression in 304 AML and 138 ALL patients. CD38 was lower in AML-M3 compared to other FAB subtypes (5% vs. 41%; P < 0.001), but was similar among ALL subtypes (56.6%; P = 0.69). Ph + ALL and AML with t(15; 17) patients showed lower CD38 expression than the other cytogenetic groups. Overall survival favored AML and ALL patients with higher CD38 levels. Multivariate analysis revealed CD38 expression to be an independent outcome predictor in AML, but not in ALL.

Origin of 2,3-pentanedione and 2,3-butanedione in D-glucose/L-alanine Maillard model systems

Model studies using independently labeled D-[(13)C]glucoses and L-[(13)C]alanines have indicated that 2,3-butanedione is formed by a single pathway involving only glucose carbon atoms, whereas 2, 3-pentanedione is formed by two pathways, one involving glucose carbon atoms (10%) and the other (90%) through the participation of C2'-C3' atoms of L-alanine and a C(3) carbon unit from D-glucose. Analysis of label incorporation into selected mass spectral fragments of 2,3-pentanedione have indicated that the C(3) carbon unit originates either from C1-C2-C3 or from C4-C5-C6 fragments of D-glucose. In addition, model studies with pyruvaldehyde and glyceraldehyde have implicated these intermediates as plausible C(3) glucose carbon units capable of producing 2,3-pentanedione upon reaction with L-alanine. The labeling studies have also confirmed a previously identified chemical transformation of alpha-keto aldehydes affected by the amino acid that leads to the addition of the C-2 atom of the amino acid to the aldehydic carbon atom of alpha-keto aldehydes.

Quantitation of minimal residual disease in acute myelogenous leukemia and myelodysplastic syndromes in complete remission by molecular cytogenetics of progenitor cells

Detection of karyotypic clonal abnormalities are prognostically useful in patients with acute myelogenous leukemia (AML) and myelodysplastic syndromes (MDS), but cytogenetic methods are not sensitive enough to detect low numbers of residual leukemic cells in patients who have achieved complete remission (CR). Fluorescence in situ hybridization (FISH) and fluorescence activated cell sorting (FACS) were used to investigate the frequency and presence of minimal residual disease (MRD) in AML and MDS patients (n = 28) with monosomy of chromosomes 7, 17 and 18 and trisomy of chromosomes 6, 8, 9 and 10 in CR. MRD was detected in all patients with monosomy 7 (n = 10) and followed by relapse in eight patients after 4.8 +/- 3.1 months. In contrast, persistent leukemic cells occurred in 11/12 patients with trisomy 8, but only three of them relapsed after 7.7 +/- 4.0 months. Cox regression analysis showed that cytogenetic class and levels of clonal cells at CR were related to time to relapse (P = 0.001). The level of MRD identified patients at high and low risk of relapse. High absolute levels of proliferating residual leukemic cells correlated with monosomy 7 and high risk of relapse.

Generation and the fate of C2, C3, and C4 reactive fragments formed in Maillard model systems of [13C]glucose and [13C]glycine or proline

Model studies with pyrolysis/GC/MS using labeled [13C] glucoses with labeled [15N/13C]glycines and proline have indicated that the Maillard model systems consisting of glucose and glycine or proline generate similar C2, C3, C4 fragments such as acetic acid, and pyruvaldehyde. Furthermore, the labeling studies have enabled the identification of the origin of these reactive intermediates and their stable end-products such as N-acetylpyrrolidine, 1-(1'-pyrrolidinyl)-2-propanone amd 1-(1'-pyrrolidinyl)-2-butanone in proline model system and pyrazines and pyrazinones in glycine. In glycine model system, pyruvaldehyde and 2,3-butandione were found to be formed either from the degradation of the carbohydrate moiety (90 and 35%, respectively) or by an aldol-type interaction of glycine with alpha-ketoaldehydes. The same intermediates in proline system are formed exclusively from the carbohydrate degradation pathway.

Multilineage involvement of Philadelphia chromosome positive acute lymphoblastic leukemia

Acute lymphocytic leukemia (ALL) is considered a clonal disease restricted to the lymphoid compartment. The Philadelphia chromosome (Ph) is found in a subset of ALL with poor prognosis. Here we present the largest series of Ph+ ALL analyzed for involvement of the myeloid compartment. For the first time at a single cell level the presence of Ph in lineages other than lymphoid is demonstrated. Granulocytes from nine patients diagnosed with BCR-ABL + ALL (eight Ph+, one Ph-) were purified using two layer density gradient separation. They were further identified by the morphology of DAPI-stained nuclei and studied for the presence of the Ph by fluorescence in situ hybridization (FISH) using a BCR-ABL dual-color probe. Ph was demonstrated in 30 to 93% of granulocytes in all patients. FISH identified major and minor BCR gene breakpoints (M-bcr and m-bcr). In one patient, with CD19+/34+/33-/2-/3-/7-/10- lymphoblasts, involvement of B cells (CD19+), T cells (CD3+), myeloid (CD13+), erythroid (glycophorin A+) cells was found by FISH following fluorescence-activated cell sorting (FACS). The diagnosis of ALL as opposed to lymphoblastic transformation of CML was established based on clinical and laboratory data including Western blot results demonstrating the presence of p190/m-bcr in five of the nine cases studied. Results suggest that Ph+ ALL originates from a pluripotent stem cell.

Minimal residual disease in acute myelogenous leukaemia and myelodysplastic syndromes: a follow-up of patients in clinical remission

The majority of patients with acute myelogenous leukaemia (AML) and myelodysplastic syndromes (MDS) relapse, especially those with unfavourable cytogenetics. This study was designed to investigate the presence and frequency of minimal residual disease (MRD) in patients with AML or MDS (n=35) and numerical abnormalities of chromosomes 6, 7, 8, 9, 10, 17 and 18 in clinical remission by using a combination of fluorescence activated cell sorting (FACS), fluorescence in-situ hybridization (FISH) and labelling with bromodeoxyuridine (BUdR). The technique enables the detection of as few as three leukaemic cells in 10(5) normal cells. MRD was detected in 33/35 patients in complete remission (CR). 16 patients relapsed (8/11 with monosomy 7, 4/17 with trisomy 8, and 4/7 with other cytogenetic abnormalities) after a median of 4.8 months (range 3-13). Levels of MRD (P=0.007) and proliferation index (P=0.011) were significantly higher in patients with monosomy 7 than in patients with trisomy 8 or other cytogenetic abnormalities. The percentage of cells in S-phase, the number of abnormal cells and cytogenetic class were related to time to relapse (P=0.001) with S-phase being the single most important prognostic factor (P=0.0001). We conclude that the combination of FACS/FISH/BUdR, which determines the number, phenotype and proliferation rate of very rare leukaemic cells in patients with AML or MDS in clinical remission, provides information that is useful in the identification of patients with high and low likelihood of relapse.

Phagocyte transport as mechanism for enhanced therapeutic activity of liposomal amphotericin B

Liposomal amphotericin B (L-AmB) is emerging as one of the most attractive new antifungal agents. We have attempted to show that phagocytic cells circulating in blood play an important role in transport and accumulation of L-AmB at inflammatory sites in vivo. Free AmB or L-AmB was injected intravenously to mice, and the amount of AmB in peritoneal exudate cells was quantitated by high-performance liquid chromatography. Higher levels of AmB were detected in a higher number of mice injected with L-AmB. The presence of L-AmB in inflammatory peritoneal cells after intravenous administration of fluorescence-labeled L-AmB also suggested that macrophages play an important role in the transport of intravenously administered L-AmB to inflammatory sites.

In vitro activities of free and liposomal drugs against Mycobacterium avium-M. intracellulare complex and M. tuberculosis

We compared MICs and MBCs of various free- and liposome-incorporated antimicrobial agents against several patient isolates of Mycobacterium avium-M. intracellulare complex and certain American Type Culture Collection strains of M. avium, M. intracellulare, and Mycobacterium tuberculosis. Seven of 19 agents were selected for incorporation into liposomes. The MICs of these agents for 50 and 90% of isolates tested (MIC50s and MIC90s, respectively) ranged from 0.5 to 62 micrograms/ml. Members of the M. avium-M. intracellulare complex were resistant to killing by most of the other agents tested in the free form. However, clofazimine, resorcinomycin A, and PD 117558 showed complete killing of bacteria at concentrations ranging from 8 to 31 micrograms/ml, represented as MBC90s. Among the liposome-incorporated agents, clofazimine and resorcinomycin A had the highest killing effects (MBC90s, 8 and 16 micrograms/ml, respectively). Furthermore, both free and liposome-incorporated clofazimine had equivalent growth-inhibitory and killing effects on all American Type Culture Collection strains of M. avium, M. intracellulare, and M. tuberculosis tested. These results show that the antibacterial activities of certain drugs, particularly those of clofazimine and resorcinomycin, were maintained after the drugs were incorporated into liposomes.

Roles of liposome composition and temperature in distribution of amphotericin B in serum lipoproteins

The role of liposome composition and temperature in the distribution of amphotericin B (AmB) with serum lipoproteins and the role of particle charge in AmB transfer to serum lipoproteins were determined. Serum obtained from healthy volunteers was incubated with known concentrations of AmB or different liposomal formulations of AmB (1 to 100 micrograms/ml) at 37 degrees C for various time intervals (5, 10, 20, 30, 45, and 60 min). After each interval, serum was removed and separated into high-density lipoprotein (HDL) and low-density lipoprotein (LDL) fractions by an LDL-direct assay. The distribution of AmB (Fungizone) at 5 min through 1 h of incubation at 25 degrees C remained constant and was similar in the HDL and LDL fractions. At 37 degrees C, at 5 through 45 min of incubation, 54 to 61% of AmB was recovered in the HDL fraction; however, at 1 h more than 75% of the AmB concentration was recovered in the HDL fraction. In contrast, 87.5 to 92% AmB was recovered in the HDL fraction throughout the incubation when negatively charged liposomal AmB (dimyristoylphosphatidylcholine [DMPC]:dimyristoylphosphatidylglycerol [DMPG], 7:3 [wt/wt]) was used. With positively charged liposomes, 75 to 87.7% of AmB was recovered in the HDL fraction through the different time points studied. AmB incorporated into DMPC (neutral) and DMPG (negative) liposomes, and AmB was distributed in an HDL:LDL ratio of 6:4 following 1 h of incubation. Ninety percent of AmB and 80% of the lipid were found in the HDL fraction in a 3:1 molar DMPG:AmB ratio and in the LDL fraction in a 6:1 molar ratio. Lipid charge and temperature play a role in AmB distribution into serum lipoproteins. AmB and DMPG may contransfer as an intact drug-lipid complex to serum lipoproteins.

Liposomal hamycin: reduced toxicity and improved antifungal efficacy in vitro and in vivo

Hamycin has been used to treat a variety of yeast and other fungal infections by oral, topical, and intraperitoneal routes. However, its parenteral use has been reported to be associated with high toxicity. Multilamellar liposomes composed of dimyristoyl phosphatidyl choline, dimyristoyl phosphatidyl glycerol, and various amounts of cholesterol were used as drug carriers for hamycin. The antifungal activity of hamycin was maintained after liposome encapsulation (MIC range, 0.6-1.2 micrograms/ml), and toxicity was reduced in vitro and in vivo as the concentration of cholesterol was increased to an appropriate ratio. Mice were treated with various doses of free or liposomal hamycin 2 days after infection. Although free drug did not significantly improve survival, liposomal hamycin at an equivalent dose (0.6 mg/kg) increased the survival from 18 to 38 days. Higher doses (1.2 and 1.8 mg/kg) showed further improvement in survival and reduction in numbers of colony-forming units in the kidneys. Liposome encapsulation resulted in improved therapeutic index of hamycin.

Antifungal activity of HWA-138 and amphotericin B in experimental systemic candidiasis

HWA-138, a pentoxifylline analog, has been shown to increase yeast urinary clearance and to reduce yeast counts in the kidneys of rats infected with Candida albicans. Furthermore, HWA-138 has also been shown to prevent amphotericin B-induced acute renal failure in rats. We report here on the effects of HWA-138 alone and in combination with amphotericin B in the treatment of systemic candidiasis in mice. When single doses of HWA-138 were administered intravenously (10, 25, or 50 mg/kg of body weight) into infected mice, no significant improvement in survival was observed. In infected mice treated intravenously with multiple doses of HWA-138 (10, 25, or 50 mg/kg once daily for 5 consecutive days), a significant increase in survival time was seen only in animals also receiving 25 mg of HWA-138 per kg (14 +/- 3 days test versus 9 +/- 1 days control; P less than 0.05). The coadministration of subtherapeutic doses of amphotericin B and HWA-138 resulted in increased survival time. Combination therapy with amphotericin B (0.1-mg/kg single dose) and HWA-138 (10-, 25-, or 50-mg/kg multiple doses) resulted in a significant increase in survival time over controls (19 +/- 4, 19 +/- 5, and 21 +/- 9 days, respectively, versus 9 +/- 3 days; P less than 0.05). Combination therapy with amphotericin B (0.2-mg/kg single dose) and HWA-138 (10-, 25-, or 50-mg/kg multiple doses) also resulted in a significant increase in survival time over controls (24 +/- 6, 24 +/- 6, and 24 +/- 6, respectively, versus 9 +/- 3 days; P less than 0.05). Combination therapy with amphotericin B (0.2-mg/kg single dose) and HWA-138 (10-, 25-, or 50-mg/kg multiple doses) also resulted in a significant increase in survival time over controls (24 +/- 6, 24 +/- 6, and 24 +/- 6, respectively, versus 9 +/- 3 days; P < 0.05). Variance analysis of these findings indicate synergistic activity between amphotericin B and HWA-138 in the treatment of experimental candidiasis in mice.

Proteolytic enzymes released by liver macrophages may promote hepatic injury in a rat model of hepatic damage

Using macrophages isolated from the livers of normal rats and from rats injected intravenously with Corynebacterium parvum 6 days previously, N-acetyl-glucosaminidase (NAG) and plasminogen activator (PA) production have been measured during in vitro culture. There was a significant increase (p less than 0.02) in the supernatant activity of NAG by the C. parvum recruited macrophages 8.05 +/- 1.17 nmol product/mg protein/h as compared with normal, 3.86 +/- 0.77 nmol product/mg protein/h. There was a similar increase in cellular NAG content by recruited macrophages 412 +/- 66 nmol product/mg protein compared with 153 +/- 35 nmol product/mg protein (p less than 0.01) in normals. When macrophages of either group were exposed in vitro to endotoxin alone or a combination of endotoxin followed by latex particles, NAG values were similar to those obtained from nonexposed cells. In contrast, PA supernatant production increased significantly (p less than 0.02) on exposure to endotoxin with a corresponding reduction in cellular PA content, but the cellular PA content and supernatant release were similar for each group of cells. There was a fourfold increase in the number of macrophages isolated from the C. parvum-treated livers/g liver weight. Thus, the hepatocytes in this model of liver injury are potentially exposed to a 10-fold increase in the concentration of the acid hydrolase NAG; potentiation of cell damage by the administration of endotoxin may be mediated through the observed increase in production of secretory enzymes such as plasminogen activator. In conclusion, this study supports the hypothesis that proteolytic products released by recruited and activated macrophages may result in hepatocyte damage.

Carcinoma of the thyroid gland in Iran

Of the 1698 cases of thyroid disease seen during the 17 years 1956-72 in the Taj Cancer Institute, Tehran, 398 were cases of carcinoma, an incidence of 23.4 per cent. The factors involved in this high incidence of malignancy are discussed and the treatment of these patients is described.