Prevention of renal stone disease recurrence. A systematic review of contemporary pharmaceutical options

Introduction: Renal stone disease has a high recurrence rate. Prompt metabolic evaluation followed by appropriate medical management is of paramount importance for preventing disease recurrence.

Areas covered: A PubMed/Medline search was performed to identify randomized controlled studies evaluating medical treatments against renal stone recurrence. Due to the limited number of published randomized studies, non-randomized studies of significant importance were included and reported.

Expert opinion: Thiazides are widely used for lowering calcium levels in urine and thus preventing calcium stone formation. Citrate supplements may increase the urine citrate level and increase pH. Allopurinol has shown significant efficacy for preventing formation of calcium stones in hyperuricosuric patients. Prevention of recurrence of infection stones and cystine stones has not been widely studied. Several agents that are used today have shown efficacy outside randomized controlled studies. However, they may produce severe adverse events, which are minimizing their use.     

Inhibitors of α-glucosidase and α-amylase from Cyperus rotundus

Context: A methanol extract of Cyperus rotundus L. (Cyperaceae) rhizomes showed inhibitory activity against α-glucosidase and α-amylase, two enzymes involve in carbohydrate digestion.

Objective: Identification of compounds from C. rotundus rhizomes responsible for the inhibition of α-glucosidase and α-amylase.

Materials and methods: Compounds were identified by a phytochemical investigation using combined chromatographic and spectroscopic methods. α-glucosidase and α-amylase inhibitory activities were evaluated by in vitro enzyme inhibition assays.

Results: A new (2RS,3SR)-3,4′,5,6,7,8-hexahydroxyflavane (1), together with three known stilbene dimers cassigarol E (2), scirpusin A (3) and B (4) were isolated. Compound 2 inhibited both α-glucosidase and α-amylase activities while the flavane 1 only showed effect on α-amylase, and compounds 3 and 4 were active on α-glucosidase. All four compounds showed significant 2,2-diphenyl-1-picrylhydrazyl (DPPH) scavenging activity.

Discussion: The inhibitory activities against α-amylase and α-glucosidase of the C. rotundus rhizomes were reported for the first time. Stilbene dimers are considered as potent inhibitors of α-glucosidase and promising antihyperglycemic agents.

Conclusion: The isolated compounds may contribute to the antidiabetic property of C. rotundus.     

Taurine reduces blue light-induced retinal neuronal cell apoptosis in vitro

Background: The massive uptake of organic compatible osmolytes is a self-protective response to multiple stressors.

Objective: This study aimed to determine the protective effects of the osmolyte taurine against blue light-induced apoptosis in retinal neuronal cells in vitro.

Methods: Real-time PCR was used to measure osmolyte transport. Radioimmunoassays were performed to measure osmolyte uptake. Cell Counting Kit-8 assays were conducted to measure cellular viability. Flow cytometry analysis was used to measure apoptosis.

Results: Compared with normotonic stress, hypertonic stress-induced uptake of osmolytes, including betaine, myoinositol, and taurine, into the retinal neuronal cells. Blue light increased osmolyte transporter mRNA expression together with osmolyte uptake. Furthermore, taurine significantly suppressed blue light-induced retinal neuronal cell apoptosis.

Conclusion: The compatible osmolyte taurine may have an important role in cell resistance to blue light and cell survival.     

Corneal perforation: another side effect of nicorandil

Context: Nicorandil is an antianginal drug used for 20 years in Japan and introduced in France in 1994. Since 1997, side effects such as mucocutaneous ulcerations have regularly been reported.

Objective: To describe the first case of a patient with a spontaneous corneal perforation associated with mucocutaneous ulcerations while taking Nicorandil.

Materials and methods: A 81-year-old patient, with no past history of ocular disease but a long past history of cardiovascular disease, presented with a spontaneous paracentral corneal perforation. This was consecutive to 5 months of recurrent keratoconjunctivitis and mucocutaneous ulcerations resistant to conventional therapy. (He was taking nicorandil for 5 years.) A penetrating keratoplasty was performed in emergency.

Results: Inflammatory and infectious causes of spontaneous corneal perforation were ruled out. After initial uneventful post-operative wound healing, an epithelial ulcer appeared on the graft. Dermatologists suggested the iatrogenic role of nicorandil and the drug was discontinued. Both mucocutaneous and corneal ulcerations resolved rapidly.

Discussion: Although mucocutaneous ulcerations have been attributed several times to nicorandil, this is, to our knowledge, the first major corneal damage due to this antianginal drug. Timing, pattern of illness, absence of other aetiology, recurrence of epithelial ulceration on the corneal graft and its spontaneous healing after nicorandil discontinuation make it highly apparent probable that nicorandil was directly involved in this corneal perforation.

Conclusion: Ophthalmologists and dermatologists should be aware of the risk of severe but reversible corneal ulcerations in patients treated with nicorandil. A pharmacovigilance warning statement should be compulsory.     

A review on phytochemical and pharmacological properties of Litsea coreana

Context: Litsea coreana H. Lév. (Lauraceae) is used as an ethnic herb or beverage in China. Substantial studies indicate that it contains a variety of compounds and shows diverse bioactivities with no toxicity.

Objective: This review analyzes and summarizes the ethnopharmacological applications, phytochemistry, and pharmacological activities and molecular mechanisms of L. coreana.

Methods: Related literature (from 1998 to 2016) was obtained and compiled via searching databases including Scopus, Web of Science, Google Scholar, CNKI and PubMed. Keywords (Litsea coreana, hawk tea, eagle tea and laoying cha) were used to select the articles.

Results: Studies indicate that L. coreana contains characteristic polysaccharides, polyphenols, essential oils, and numerious flavonoids, which exhibit remarkable bioactivities, such as hepatoprotection, hyperglycaemia, anti-inflammation, antioxidation and antibacterial, through multiple molecular mechanisms.

Conclusion: This paper provides a systematic review on the phytochemicals and pharmacological activities of L. coreana which should be useful for further study and application of this medicinal herb.     

Echinacea biotechnology: advances,commercialization and future considerations

Context: Plants of the genus Echinacea (Asteraceae) are among the most popular herbal supplements on the market today. Recent studies indicate there are potential new applications and emerging markets for this natural health product (NHP).

Objective: This review aims to synthesize recent developments in Echinacea biotechnology and to identify promising applications for these advances in the industry.

Methods: A comprehensive survey of peer-reviewed publications was carried out, focusing on Echinacea biotechnology and impacts on phytochemistry. This article primarily covers research findings since 2007 and builds on earlier reviews on the biotechnology of Echinacea.

Results: Bioreactors, genetic engineering and controlled biotic or abiotic elicitation have the potential to significantly improve the yield, consistency and overall quality of Echinacea products. Using these technologies, a variety of new applications for Echinacea can be realized, such as the use of seed oil and antimicrobial and immune boosting feed additives for livestock.

Conclusions: New applications can take advantage of the well-established popularity of Echinacea as a NHP. Echinacea presents a myriad of potential health benefits, including anti-inflammatory, anxiolytic and antibiotic activities that have yet to be fully translated into new applications. The distinct chemistry and bioactivity of different Echinacea species and organs, moreover, can lead to interesting and diverse commercial opportunities.     

Hyaluronic acid modified daunorubicin plus honokiol cationic liposomes for the treatment of breast cancer along with the elimination vasculogenic mimicry channels

Background: Breast cancer is an alarming global public health problem and a main cause of cancer-related death in women. Systemic chemotherapy is the most widely used treatment for breast cancer. However, current chemotherapy treatments are far from desirable due to poor targeting specificity, severe side effects and vasculogenic mimicry (VM).

Purpose: Hyaluronic acid (HA)-modified daunorubicin plus honokiol (HNK) cationic liposomes were prepared and characterised for treatment of breast cancer by eliminating VM.

Methods: HA-modified daunorubicin plus HNK cationic liposomes were prepared by a thin-film hydration method. Evaluations were performed on MCF-7 cells and MDA-MB-435S cells, which are human breast cancer cells, and xenografts of MDA-MB-435S cells.

Results: In vitro results revealed that the HA-modified daunorubicin plus HNK cationic liposomes enhanced the cellular uptake and destroyed VM channels. In vivo results demonstrated that the liposomes prolonged the circulation time in the blood, obviously accumulated in the tumour region, and enhanced the overall anticancer effects. Action mechanisms were related to down-regulation of VM protein indicators including FAK, EphA2, MMP-2 and MMP-9.

Conclusions: The prepared HA-modified daunorubicin plus HNK cationic liposomes may serve as a promising therapeutic strategy for the treatment of breast cancer.     

Monoterpenoids from the whole herb of Veronicastrum axillare

Context: Veronicastrum axillare (Sieb. et Zucc.) Yamazaki (Scrophulariaceae) embraces varieties of bioactivities such as anti-inflammatory, anti-pyresis and detoxification activity, while little is known of the phytochemical components of this medicinal plant.

Objective: To isolate and identify bioactive constituents from the whole herb of V. axillare.

Materials and methods: Ethanol extract of the whole herb of V. axillare was subjected to successive column chromatography. Chemical structures of the compounds were elucidated by detailed spectroscopic analyses on the basis of NMR, IR and HR-MS data.

Results: A new monoterpenoid, axillacetal A (1) and a known analogue, tarumal (2), were isolated from the whole herb of V. axillare. The structure of tarumal (2) was also revised according to our NMR data.

Discussion and conclusion: This is the first report on the isolation and authentication of novel chemical constituents from V. axillare.     

Current and emerging drug options in the treatment of diarrhea predominant irritable bowel syndrome

Introduction: Irritable bowel syndrome diarrhea predominant (IBS-D) is a highly prevalent GI disease, affecting nearly a third of all patients diagnosed with irritable bowel syndrome. Current treatment options are limited.

Areas covered: This review discusses the pharmacotherapeutic options for IBS-D including currently used medications, the two newly FDA approved medications, as well as emerging therapies with potential benefit in IBS-D. Particular emphasis is placed on rifaximin and eluxadoline and their possible use in IBS-D.

Expert Opinion: Current pharmacological treatment of IBS-D includes loperamide, bile acid sequestrants, antispasmodics, tricyclic antidepressants, alosetron, eluxadoline and rifaximin. The latter two treatments have significantly added to the pharmacotherapeutic options for patients suffering from IBS-D.     

Dosing strategies to optimize currently available anti-MRSA treatment options (Part 2: PO options)

Introduction: Methicillin-resistant Staphylococcus aureus (MRSA) is a problematic pathogen in both outpatient and inpatient settings. Research to optimize the dosing of these agents is needed to slow the development of antimicrobial resistance and to decrease the likelihood of clinical failure.

Areas covered: This review summarizes the available data for orally administered antimicrobials routinely used as monotherapy for MRSA infections. We make recommendations and highlight the current gaps in the literature. A PubMed (1966 – Present) search was performed to identify relevant literature for this review.

Expert commentary: There is a vast divide in the amount of pharmacokinetic/pharmacodynamic data to guide dosing decisions for older MRSA agents compared with the oxazolidenones.

Five-year view: Additional retrospective data will become available for the older MRSA agents in severe MRSA infections.     

Can binimetinib,encorafenib and masitinib be more efficacious than currently available mutation-based targeted therapies for melanoma treatment?

Introduction: Historically, there were few effective and durable treatments for metastatic melanoma. Recently, mutation based targeted therapies have revolutionized treatment and outcomes for patients with metastatic melanoma. Specifically, inhibitors aimed at BRAF, NRAS, and C-KIT mutations are now commonly used in treatment for patients harboring the specific mutations.

Areas covered: A brief review of current BRAF, NRAS, and C-KIT inhibitors provides background for a thorough review of newly developed agents namely binimetinib, a MEK inhibitor, encorafenib a BRAF inhibitor, and masitinib which inhibits C-KIT.

Expert opinion: While the 3 novel agents reviewed here have potential for use in melanoma, optimal utilization will occur once a more personalized approach incorporating genomic, proteomic, and immunologic data guides therapeutic decisions.     

Decreased viability and proliferation of CHANG conjunctival epithelial cells after contact with ultraviolet light-irradiated pollen

Context: Contact with pollen is the major reason for the development of allergic symptoms on the ocular surface leading to a significant increase of allergic diseases worldwide. Environmental changes such as increased ultraviolet (UV) radiation and air pollution are discussed as contributory causes for this increase.

Objective: We investigated the effect of UV light on the histamine content of pollen and examined if an irradiation of pollen affects the viability and proliferation of conjunctival cells.

Materials and methods: Alder (Alnus glutinosa) and hazel (Corylus avellana) pollen were irradiated for different time periods with sunlight, UV-A or UV-B light and the histamine content was analysed and compared with non-irradiated pollen. Conjunctival epithelial cells (CHANG cells) were exposed to irradiated and non-irradiated pollen followed by an assessment of cell viability with the colorimetric MTS test and the impedance-based measurement of cell proliferation using the xCELLigence real-time analysis system.

Results: UV light irradiation increased the histamine level of alder and hazel pollen in a dose-dependent manner. CHANG cells treated with irradiated pollen induced a statistically significant higher decrease of cell viability than treatment with non-irradiated pollen.

Discussion and conclusions: Our results indicate that UV light is able to alter pollen thus making them more harmful for conjunctival cells.     

First-line treatment in the management of advanced renal cell carcinoma: systematic review and network meta-analysis

Objectives: To conduct a systematic review and network meta-analysis (NMA) to assess effectiveness of first-line treatments for advanced renal cell carcinoma (RCC).

Methods: Database searches were conducted to identify randomized controlled trials (RCTs) reporting results for eligible treatments. A fixed-effect Bayesian NMA was conducted to assess the relative effectiveness of treatments, with progression-free survival (PFS) reported as hazard ratios (HRs) and 95% credible intervals (CrIs).

Results: Eleven unique RCTs were suitable for inclusion in the NMA. In the base case, in terms of PFS, sunitinib was superior compared with bevacizumab + IFN-α (HR = 0.79, 95% CrI: 0.64 – 0.96), everolimus (HR = 0.70, 95% CrI: 0.56 – 0.87), sorafenib (HR = 0.56, 95% CrI: 0.40 – 0.77) and temsirolimus + bevacizumab (HR = 0.74, 95% CrI: 0.56 – 0.96). Although, the point values for the mean and median HRs were < 1.0, there was no significant difference in PFS between sunitinib and axitinib, pazopanib or tivozanib. Although sensitivity analyses impacted the results of the NMA, no treatment was significantly more efficacious than sunitinib.

Conclusion: Results from this analysis suggest that there is no treatment superior to the current benchmark treatment, sunitinib, in the management of advanced RCC in the first-line setting.     

Overcoming platinum resistance in ovarian cancer treatment: from clinical practice to emerging chemical therapies

Introduction: The objective of this review is to summarize results from clinical trials that tested cytotoxic drugs and target strategies for the treatment of platinum resistant (PR) recurrent ovarian cancer (ROC) with particular attention to Phase III and ongoing trials.

Areas covered: Since platinum free interval (PFI) represents the most important predictive factor for response to platinum re-treatment in ROC, non-platinum regimens are conventionally considered the most appropriate approaches.

Impressive progress has been made in recent decades, resulting in the identification of most effective cytotoxic agents and in the development of new target strategies.

However, the efficacy of most of these drugs for the treatment of PR disease is still limited.

Expert opinion: The most favorable benefit for the treatment of PR disease, has been described by the AURELIA trial that showed a 3.3 months increase in progression free survival (PFS) when bevacizumab was combined with non-platinum single agent chemotherapy in bevacizumab-naïve patients.

Nevertheless, the use of novel agents is associated to important costs for just little gains in survival.

Thus, in our opinion the economic evaluation, such as the incorporation of quality of life into the clinical studies is crucial for the development of future trials for PR-ROC.     

Safety of anticonvulsant agents in pregnancy

Introduction: Seizures in pregnancy are particularly challenging, as their management requires careful consideration of not only the etiology of the seizure, but also the physiologic changes of pregnancy as well as potential adverse effects on the developing embryo or fetus. Newer antiepileptic drugs (AEDs) have increasingly shown promising results of lower rate of teratogenesis, as well as better seizure control during pregnancy.

Areas covered: We performed a review of the scientific literature of seizures in pregnancy including status epilepticus as well as eclampsia, with a focus on safety of currently used AEDs. This covers the different generations of antiepileptic medications, their interactions and seizure recurrence preventative measures. In addition, we summarized our personal approach to the care for these women.

Expert opinion: In summary, morbidity associated with seizure in pregnancy is decreasing as treatments and supportive therapies have improved. The understanding of teratogenesis as well as novel targeted therapeutics will allow women on AEDs during their pregnancy, to receive the safest drug for their developing fetus as well as themselves.     

Taurine prevents ultraviolet B induced apoptosis in retinal ganglion cells

Background: Compatible osmolytes accumulation is an active resistance response in retina under ultraviolet (UV) radiation and hypertonicity conditions.

Objective: The purpose of this research is to investigate the protective role of taurine on retina under UVB radiation.

Methods: Osmolytes transporters were measured by quantitative realtime PCR. Osmolytes uptake was estimated by radioimmunoassay. Cell viability was calculated by MTT assay. Cell apoptosis was measured by flow cytometry analysis.

Results: Hypertonicity accelerated osmolytes uptake into retinal ganglion cells (RGCs) including taurine, betadine, and myoinositol. UVB radiation increased osmolytes transporter expression and osmolytes uptake. In addition, osmolyte taurine remarkably prevented UVB radiation induced cell apoptosis in RGCs.

Conclusions: The effect of compatible osmolyte taurine on cell survival rate may play an important role in cell resistance and adaption to UVB exposure.     

Modulating release of ranibizumab and aflibercept from thiolated chitosan-based hydrogels for potential treatment of ocular neovascularization

Background: This paper describes the synthesis of thiolated chitosan-based hydrogels with varying degrees of crosslinking that has been utilized to modulate release kinetics of two clinically relevant FDA-approved anti-VEGF protein drugs, ranibizumab and aflibercept. These hydrogels have been fabricated into disc shaped structures for potential use as patches on ocular surface.

Methods: Protein conformational changes and aggregation after loading and release was evaluated by circular dichroism (CD), steady-state tryptophan fluorescence spectroscopy, electrophoresis and size-exclusion chromatography (SEC). Finally, the capacity of both released proteins to bind to VEGF was tested by ELISA and surface plasmon resonance (SPR) technology.

Results: The study demonstrates the versatility of thiolated chitosan-based hydrogels for delivering proteins. The effect of various parameters of the hydrogel on protein release kinetics and mechanism of protein release was studied using the Korsmeyer-Peppas release model. Furthermore, we have studied the stability of released proteins in detail while comparing it with non-entrapped proteins under physiological conditions to understand the effect of formulation conditions on protein stability.

Conclusions: The disc-shaped thiolated chitosan-based hydrogels provide a potentially useful platform to deliver ranibizumab and aflibercept for the treatments of ocular diseases such as wet AMD, DME and corneal neovascularization     

Impact of bodyweight/body mass index on the effectiveness of emergency contraception with levonorgestrel: a pooled-analysis of three randomized controlled trials

Objective:

A pooled analysis of two randomized controlled trials (RCTs) suggested that increased bodyweight and body mass index (BMI) may be associated with a greater probability of pregnancy. To address this issue we investigated whether higher bodyweight and/or BMI negatively impacted the risk of pregnancy in women receiving LNG-EC (levonorgestrel – emergency contraception) after unprotected sexual intercourse in a pooled analysis of three large multinational RCTs conducted by the World Health Organization (WHO).

Methods:

A pooled analysis of three double-blind, multinational RCTs conducted by the WHO to investigate the efficacy of LNG-EC in the general population. All analyses were done on the per-protocol set (PPS) which included 5812 women who received LNG-EC within 72 hours following unprotected sexual intercourse. The analysis was based on logistic regression, with pregnancy as the outcome. BMI and weight were represented in the same model.

Results:

A total of 56 pregnancies were available for analysis in the PPS. Increasing bodyweight and BMI were not correlated with an increased risk of pregnancy in the studied population. A limitation of this study is that despite the large study population in the pooled analysis there were relatively small numbers of women in the high-BMI and high-bodyweight subgroups.

Conclusion:

LNG-EC is effective for preventing pregnancy after unprotected intercourse or contraceptive failure and no evidence was found to support the hypothesis of a loss of EC efficacy in subjects with high BMI or bodyweight. Therefore, access to LNG-EC should not be limited only to women of lower bodyweight or BMI.     

Conventional- versus high-dose vancomycin regimen in patients with acute bacterial meningitis: a randomized clinical trial

Objective: Efficacy of the conventional- versus high-dose vancomycin regimen in patients with acute bacterial meningitis was compared.

Methods: In a randomized clinical trial 44 patients with acute bacterial meningitis were randomly assigned to the conventional- or high-dose vancomycin groups. Clinical and laboratory parameters were used for evaluation of response to the treatment regimens.

Results: In the high-dose group, leukocytosis and fever resolved significantly faster than those in the conventional group. Furthermore, the length of hospitalization was shorter and Glasgow Coma Scale at the end of 10th day was significantly lower in the high dose compared to the conventional group. Trend of creatinine clearance changes did not differ significantly between the two groups.

Conclusion: In comparison to the conventional-dose regimen, the high-dose vancomycin regimen was associated with significantly more favorable clinical response without increase in the incidence of nephrotoxicity in patients with acute bacterial meningitis.