A pH-sensitive silica nanoparticles for colon-specific delivery and controlled release of catechin: Optimization of loading efficiency and in vitro release kinetics.

Catechin is a naturally occurring flavonoid of the flavan-3-ol subclass with numerous biological functions; however, these benefits are diminished due to several factors, including low water solubility and degradation in the stomach's harsh environment. So, this study aimed to develop an intelligent catechin colon-targeting delivery system with a high loading capacity. This was done by coating surface-decorated mesoporous silica nanoparticles with a pH-responsive enteric polymer called Eudragit®-S100. The pristine wormlike mesoporous silica nanoparticles (< 100 nm) with high surface area and large total pore volume were effectively synthesized and modified with the NH2 group using the post-grafting strategy. Various parameters, including solvent polarity, catechin-carrier mass ratio, and adsorption time, were studied to improve the loading of catechin into the aminated silica nanoparticles. Next, the negatively charged Eudragit®-S100 was electrostatically coated onto the positively charged aminated nanocarriers to shield the loaded catechin from the acidic environment of the stomach (pH 1.9) and to facilitate site-specific delivery in the acidic environment of the colon (pH 7.4). The prepared nanomaterials were evaluated using several methods, including The Brauner-Emmett-Teller, surface area analyzer, zeta sizer, Field Emission Scanning Electron Microscope, Powder X-Ray Diffraction, Fourier Transform Infrared Spectroscopy, Energy-Dispersive X-ray Spectroscopy, and Differential Scanning Calorimetry. In vitro dissolution studies revealed that Eudragit®-S100-coated aminated nanomaterials prevented the burst release of the loaded catechin in the acidic environment, with approximately 90% of the catechin only being released at colonic pH (pH > 7) with a supercase II transport mechanism. As a result, silica nanoparticles coated with Eudragit®-S100 would provide an innovative and promising approach in targeted nanomedicine for the oral delivery of catechin and related medicines for treating diseases related to the colon, such as colorectal cancer and irritable bowel syndrome.

Genome-wide profiling of transcription factor activity in primary liver cancer using single-cell ATAC sequencing.

Primary liver cancer (PLC) consists of two main histological subtypes; hepatocellular carcinoma (HCC) and intrahepatic cholangiocarcinoma (iCCA). The role of transcription factors (TFs) in malignant hepatobiliary lineage commitment between HCC and iCCA remains underexplored. Here, we present genome-wide profiling of transcription regulatory elements of 16 PLC patients using single-cell assay for transposase accessible chromatin sequencing. Single-cell open chromatin profiles reflect the compositional diversity of liver cancer, identifying both malignant and microenvironment component cells. TF motif enrichment levels of 31 TFs strongly discriminate HCC from iCCA tumors. These TFs are members of the nuclear/retinoid receptor, POU, or ETS motif families. POU factors are associated with prognostic features in iCCA. Overall, nuclear receptors, ETS and POU TF motif families delineate transcription regulation between HCC and iCCA tumors, which may be relevant to development and selection of PLC subtype-specific therapeutics.

Is there a therapeutic potential in combining bupropion and naltrexone in schizophrenia?

INTRODUCTION: A sustained-release tablet composed of a combination of the dopamine and norepinephrine reuptake inhibitor bupropion (BUP) and the µ-opioid receptor antagonist naltrexone (NAT) is marketed under the brand name Contrave by Orexigen Therapeutics for appetite control. Minimal literature is available regarding the use of combination bupropion and naltrexone (BUPNAT) in individuals with schizophrenia. AREAS COVERED: In this review, we propose a theoretical model where BUPNAT may have a therapeutic effect in the treatment of schizophrenia. We explore the pathways targeted by the constituent drugs BUP and NAT and summarize the literature on their efficacy and possible adverse effects. We then look at the potential use of BUPNAT in schizophrenia. EXPERT OPINION: Research has hinted that BUP's dopaminergic properties affect the same striatal pathways involved in schizophrenia. NAT, via opioid receptor antagonism, indirectly increases striatal dopamine release by disinhibiting nicotinic acetylcholine receptors. As such, we hypothesize that BUPNAT can have a therapeutic effect in schizophrenia, particularly on negative symptoms. We also suggest that it may ameliorate comorbidities frequently seen in this group of patients, including obesity, smoking, and substance use. Further research and clinical data are needed to elucidate the potential clinical benefits of BUPNAT in the treatment of schizophrenia.

Synthesis and Evaluation of High Functionality and Quality Cell-penetrating Peptide Conjugated Lipid for Octaarginine Modified PEGylated Liposomes In U251 and U87 Glioma Cells.

The use of peptide ligand modified PEGylated liposomes has been widely investigated for tumor targeting. Peptides are mainly inserted in the liposomal lipid bilayer using PEG2K-lipid spacer (Peptide-PEG2K-DSPE). However, a lower cellular uptake from longer nonlinear PEG2K spacer was reported, we here synthesized a high functionality and quality (HFQ) lipid with a short, linear serine-glycine repeated peptide [(SG)5] spacer. The objective of the current study is to develop novel octaarginine (R8) peptide-HFQ lipid grafted PEGylated liposomes for glioma cells targeting. In vitro liposomes characterization showed that the mean particle size of all liposomal formulations was in the nano-scale range < 120 nm, with a small PDI value (i.e. ∼0.2) and had a spherical shape under Transmission Electron Microscope, indicating a homogenous particle size distribution. The flow cytometry in vitro cellular association data with U251 MG and U87 cells revealed that 1.5% R8-(SG)5-lipid-PEGylated liposomes exhibited significantly higher cellular association of ∼15.87 and 7.59-fold than the conventional R8-PEG2K-lipid-PEGylated liposomes (10.4 and 6.19-fold), respectively, relative to the unmodified PEGylated liposomes. Moreover, intracellular distribution studies using confocal laser scanning microscopy (CLSM) corroborated the results of the in vitro cell association. The use of ligand-HFQ-lipid liposomes could be a potential alternative to ligand-PEG2K-lipid-modified liposomes as a drug delivery system for tumor targeting.

Cleaning of oil-polluted bottom sediments of the boreal lake, Samotlor oil field, North Russia: case report.

Small lakes in areas of intensive crude oil production may be susceptible to oil pollution arising from accidental spills and leaks, eventually leading to the pollution of bottom sediments. Effective cleaning of aquatic bottom sediments remains a challenge. Flotation is a potentially simple and reliable approach for the cleanup of bottom sediments without their excavation from the water body. Full-scale testing of flotation-based technology using the specially designed airlift plant allowed the cleaning of bottom sediments of an unnamed boreal lake ('the lake') within the Samotlor oil field, North Russia, heavily polluted with crude oil several decades ago. The lake bottom sediments are dominated by peat and unevenly polluted with oil. The average oil content in the lake bottom sediments was 111 g kg-1. During the 1.5 months' field test in July-August 2018, the average total oil concentration in the bottom sediments of the lake was reduced to 1.99 g kg-1. Secondary water contamination was minimal; the content of oil hydrocarbons in the water after completion of work did not exceed 0.09 ± 0.04 mg L-1. This study demonstrates that flotation-based technology can be applied for in situ cleaning of oil-contaminated lake bottom sediments including those in boreal climates.

Novel biomarker signatures for idiopathic REM sleep behavior disorder: A proteomic and system biology approach.

OBJECTIVE: To perform a rigorous in-depth proteomics analysis to identify circulating biomarker signatures for idiopathic REM sleep behavior disorder (RBD), capable of providing new insights into the underlying pathogenic mechanisms and putative α-synuclein-related neurodegenerative processes. METHODS: Serum samples from patients with idiopathic RBD (n = 9) and healthy controls (n = 10) were subjected to a thorough liquid chromatography-mass spectrometry (MS)/MS proteomics analysis using ultimate 3,000 nanoLC interfaced to an ESI-orbitrap velos. Data were analyzed with a systems biology approach to identify altered pathways in RBD. RESULTS: We identified 259 proteins, 11 of which displayed significantly altered expression level in patients with RBD as compared to controls. Significant reduction in serum levels of dopamine ß-hydroxylase (DBH) and vitamin D binding protein (GC) were consistent with alterations in the norepinephrinergic (NErgic) and dopaminergic systems, respectively. Additional altered protein profiles indicated that immunity, inflammation, complement, and coagulation also play a role in RBD pathophysiology. CONCLUSIONS: Our results shed light on the protein signature profile, molecular pathways, and mechanisms involved in the pathogenesis of RBD and its clinical manifestation. This knowledge opens a new avenue towards more accurate and timely diagnosis and characterization of RBD, which might ultimately translate into new therapeutic strategies with disease-modifying effects. Further evaluation of the identified markers is required to confirm their diagnostic value and potential to guide clinical decision-making.

Risk of obstructive sleep apnea and excessive daytime sleepiness in hospitalized psychiatric patients.

OBJECTIVES: This study evaluated the risk of developing obstructive sleep apnea (OSA) and excessive daytime sleepiness (EDS) in hospitalized psychiatric patients at the American University of Beirut Medical Center (AUB-MC). Factors associated with OSA and EDS occurrence in this sample were also examined. METHODS: The Berlin questionnaire and the Epworth sleepiness scale; which respectively evaluate OSA and EDS symptoms, were administered to individuals hospitalized at an acute psychiatric treatment unit at the AUB-MC between the dates of January 2014 and October 2016. Additional data collected included general demographics, psychiatric diagnoses, and questionnaires evaluating depression and anxiety symptoms. Statistical analyses utilizing SPSS were performed to determine the prevalence of OSA and EDS, as well as their respective associations with patient profiles. RESULTS: Our results showed that 39.5% of participants were found to have a high risk of sleep apnea and 9.9% of the participants were found to have abnormal daytime sleepiness. The risk of developing OSA was associated with a higher body mass index (BMI) (P=0.02), and depression severity (patient health questionnaire 9 score) (P=0.01). Increasing severity of depressive symptoms was associated with a higher risk of sleep apnea (P=0.01). BMI (odds ratio [OR] =5.97, 95% confidence interval [CI] 1.89-18.82) and depression severity (OR =4.04, 95% CI 1.80-9.07) were also found to be predictors of OSA. The psychiatric diagnoses of the participants were not found to have a significant association with the risk of sleep apnea. CONCLUSION: The risk of OSA is increased among hospitalized psychiatric patients, and this condition can have detrimental effects on psychiatric patients. OSA appears to be under-recognized in this population, psychiatrists should screen for OSA in hospitalized psychiatric patients and refer them for diagnostic testing or treatment when indicated.

Evaluation of ethanolamine oleate sclerotherapy on the submandibular glands of canines as a potential therapy for sialorrhea.

BACKGROUND: Sialorrhea can have major negative effects on the physical and social well-being. Sclerotherapy may be useful in patients with sialorrhea by decreasing the amount of saliva production. The aim of this study was to test the effect of ethanolamine oleate (EO) in an experimental model as a preliminary step for its application in humans. METHODS: Histopathological and morphometric analysis of submandibular glands from thirteen dogs was preformed. A total of 25 glands were injected with 1ml of 2.5% EO (n=5), 1ml of 5% EO (n=5), 5ml of 2.5% EO (n=5) and 5ml of 5% EO (n=5). Five glands were used as control. RESULTS: EO significantly induced a dose dependent scaring of the gland ending in lobular transformation (salivary gland cirrhosis). Morphometric measurements showed that 1ml of 2.5% or 5% EO significantly induced fibrosis compared to normal glands (p=0.014 and 0.021, respectively). Fibrosis significantly increased and was more apparent when a dose of 5ml of 2.5% EO or 5% EO were injected [by semi-quantitative evaluation (p=0.016 and 0.002, respectively) and morphometric measurements (p=0.016 and 0.008, respectively)]. This scarring effect was significantly associated with reduction of area of acinar cells when a dose of 1ml-5%, 5ml-2.5% or 5ml-5% EO were applied (p=0.03. 0.012 and 0.004, respectively). Moreover, ductal injury was only significant when a dose of 5ml of 5% EO was used (p=0.034). This dose and concentration (i.e. 5ml-5% EO) had a significant synergetic effect [p=0.0119]. CONCLUSION: In this model, treatment with EO proved to permanently reduce the acinar area through induction of progressive, irreversible and dose dependant scarring (medical sialoadenectomy).

SmartPill technology provides safe and effective assessment of gastrointestinal function in persons with spinal cord injury.

STUDY DESIGN: Spinal cord injury (SCI) results in gastrointestinal (GI) complications, including gastroesophageal reflux disease and constipation, but much of the data is based on older technology. OBJECTIVE: GI transit times were determined in subjects with SCI using a new device called a SmartPill. Our principal goal was to assess whether this new technology can be applied in persons with SCI. METHODS: SCI and age- and gender-matched able-bodied (AB) control subjects not taking proton pump inhibitors were studied. Following an 8-h overnight fast, subjects consumed 120 g EggBeaters (60 kcal), two slices of white bread (120 kcal) and 30 g strawberry jam (74 kcal). A pH calibrated SmartPill capsule was swallowed with 8 ounces of water, after which subjects fasted for an additional 6 h prior to consuming an Ensure Plus nutrition shake (350 kcal). Subjects remained fasted for an additional 2 h, after which time they resumed their regular diets. RESULTS: Twenty subjects with SCI and 10 AB control subjects were studied. Data are expressed as mean±s.d. Comparing the group with SCI to the AB control group, gastric emptying time (GET), colonic transit time (CTT) and whole gut transit time (WGTT) were prolonged (GET: 10.6±7.2 vs 3.5±1.0 h, P<0.01; CTT: 52.3±42.9 vs 14.2±7.6 h, P=0.01; WGTT: 3.3±2.5 vs 1.0±0.7 days, P<0.01). No complications or side effects were reported. CONCLUSION: Our results indicate that the SmartPill technology is a safe, non-invasive assessment technique that provides valid diagnostic information in persons with SCI.

Lindane-induced biochemical perturbations in rat serum and attenuation by omega-3 and Nigella sativa seed oil.

Lindane (gamma-hexachlorocyclohexane, gamma-HCH), a highly persistent organochlorine insecticide is neurotoxic at acute doses and has been reported to induce oxidative stress in cells and tissues. In this study, we investigated the antioxidant property of Nigella sativa seed oil (N.O) and omega-3 polyunsaturated fatty acids (omega3) against gamma-HCH-induced oxidative hepatic and renal damage in male rats serum. Rats were orally given sublethal dose of gamma-HCH (12 mg/kg, 24 h prior to decapitation), while N.O (0.3 ml/kg) and omega3 (20 mg/kg) were given every 48 h for 20 days single or together, or also combined with gamma-HCH. gamma-HCH caused a significant increase in the levels of serum total lipids, cholesterol, and triglycerides by 49, 61 and 30% respectively, while HDL-cholesterol decreased by 45% compared to control group. Pretreatment with omega3 and N.O prior gamma-HCH administration re-established the altered biochemical features and alleviated the harmful effects of gamma-HCH on lipid profile. The concentration of serum total protein and albumin was significantly decreased by 35 and 45% respectively in rats treated with gamma-HCH compared to control. gamma-HCH also caused hepatic and renal damage, as observed from the elevated serum levels of urea, creatinine, total bilirubin and uric acid contents and aminotransferases (AST and ALT), phosphatases (ACP and ALP) and lactate dehydrogenase (LDH) activities. Co-administration of omega3 and N.O reversed the hazardous effects induced by gamma-HCH on the liver and kidney and also protected acetylcholinesterase from the inhibitory action of gamma-HCH as well as suppressed the lipid peroxidation. Thus, the results show that omega3 and N.O might prevent oxidative stress and attenuate the changes in the biochemical parameters induced by gamma-HCH in male rats.

Preparation and evaluation of fast-release mephenamic acid microspheres.

Mephenamic acid is characterized by low solubility, which affects its dissolution rate and bioavailability. The objective of this study was to develop fast-release microspheres of ammonium salt of the drug (AMM) by emulsion congealing.The effect of polymer, drug to polymer ratio, surfactant, type and volume of oil phase, stirring rate, microsphere size, encapsulation efficiency and stability of the microspheres were investigated. The results pointed out a good yield (69–98%) and encapsulation efficiency (71–100%). Optimum conditions include moderate molecular weight PEG, inclusion of Tween 20 and/or Span 80, high ratio of PEG (1 : 4, drug : PEG), use of mineral oil and high stirring rate (2000 rpm). Dissolution efficiency ranged between 57% and 90%. Effect of ageing on drug content and release revealed that the microspheres prepared remained stable throughout 1 year of storage. The described method was simple, efficient and resulted in stable microspheres with enhanced drug release.

Removal of o-nitrophenol from water by electrochemical degradation using a lead oxide/titanium modified electrode.

This study examined o-nitrophenol removal from aqueous solutions by electrochemical oxidation employing a modified electrode. The modified electrode was produced by electrodepositing lead oxide onto a titanium substrate. Following electrochemical oxidation of o-nitrophenol-containing solutions, the remaining o-nitrophenol concentration and chemical oxygen demand (COD) values were determined. The optimum parameters were current density of 40 mA cm(-2), pH of 2.47, 60 min of electrolysis time, 4 g L(-1) NaCl electrolyte solution and temperature of 30 degrees C. Under these optimum conditions of electrochemical degradation using a lead oxide/titanium modified electrode complete removal of o-nitrophenol and COD was achieved.

HIV type 1 subtype A epidemic in injecting drug user (IDU) communities in Iran.

HIV-1 C2-V3 subgenomic regions of the env gene from Iranian seropositive injecting drug users (IDUs) living in Mashhad have been analyzed to evaluate molecular and phylogenetic relationships with IDUs living in Tehran and identify possible common founder virus isolates. The results show that the viral sequences of the Iranian IDUs are strongly related and form a single cluster within the A subtype related to African Ugandan/Kenyan sub-Saharan isolates. Pairwise nucleotide alignment shows higher average divergence values within the Mashhad group than the Tehran group. Furthermore, the Mashhad sequences show much less conserved amino acid residues in the V3 loop than the Tehran sequences. These data represent the first macro-analysis of the HIV-1 molecular evolution in the Iran and Middle East epidemics and may be extremely relevant to guide the development and implementation of diagnostic as well as preventive/therapeutic approaches in this region.

Molecular and phylogenetic analysis of HIV-1 variants circulating among injecting drug users in Mashhad-Iran.

Genetic and phylogenetic information on the HIV-1 epidemic in Middle-East Countries, and in particular in Iran, are extremely limited. By March 2004, the Iranian Ministry of Health officially reported a cumulative number of 6'532 HIV positive individuals and 214 AIDS cases in the Iranian HIV-1 epidemic. The intra-venous drug users (IDUs) represent the group at highest risk for HIV-1 infection in Iran, accounting for almost 63% of all HIV-infected population. In this regards, a molecular phylogenetic study has been performed on a sentinel cohort of HIV-1 seropositive IDUs enrolled at the end of 2005 at the University of Mashhad, the largest city North East of Tehran. The study has been performed on both gag and env subgenomic regions amplified by Polymerase Chain Reaction (PCR) from peripheral blood mononuclear cells (PBMCs) and characterized by direct DNA sequence analysis. The results reported here show that the HIV-1 subtype A is circulating in this IDUs sentinel cohort. Moreover, the single phylogenetic cluster as well as the intra-group low nucleotide divergence is indicative of a recent outbreak. Unexpectedly, the Iranian samples appear to be phylogenetically derived from African Sub-Saharan subtype A viruses, raising stirring speculations on HIV-1 introduction into the IDUs epidemic in Mashhad. This sentinel study could represent the starting point for a wider molecular survey of the HIV-1 epidemics in Iran to evaluate in detail the distribution of genetic subtypes and possible natural drug-resistant variants, which are extremely helpful information to design diagnostic and therapeutic strategies.

Electrodegradation of methylene blue dye in water and wastewater using lead oxide/titanium modified electrode.

A modified electrode was prepared by the electrodeposition of a lead oxide layer on a titanium substrate. This electrode was used as an anode for electrocatalytic oxidation process of dyestuff in aqueous solution. The modified electrode was used for electrochemical degradation of methylene blue dye. The results of the electrocatalytic oxidation process of the dyestuff solutions were expressed in terms of the remaining dye concentration and chemical oxygen demand (COD) values. Different operating conditions and factors that affected the treatment process including current density, pH, initial dye concentration, conductive electrolyte and time of electrolysis were studied. The optimum operating conditions for the dye and modified electrode were investigated. This has resulted in complete removal of the dye and COD. The optimum conditions were applied to the treatment of methylene blue dye in real wastewater solutions. These results indicate that the suggested modified electrode was highly efficient in the treatment of effluents containing methylene blue dye with very slight effect of matrix. This electrochemical system is robust in structure and simple in operation. It has the potential to be developed as a feasible and an effective wastewater treatment process.

A C77G point mutation in CD45 exon 4, which is associated with the development of multiple sclerosis and increased susceptibility to HIV-1 infection, is undetectable in Japanese population.

HTLV-1 associated myelopathy/tropical spastic paraparesis (HAM/TSP) is one outcome of Human T-cell lymphotropic virus type 1 (HTLV-1) infection. It remains unknown why the majority of infected people remain healthy whereas only approximately 2-3% develop disease. Recently, heterozygous state of CD45 exon 4 mutation (C77C wild type and C77G mutant) was reported to be associated with development of multiple sclerosis in German patients and increased susceptibility to HIV-1 infection in the United Kingdom. To investigate whether this mutation is associated with the development of HAM/TSP, we studied a group of 164 HAM/TSP patients and 108 asymptomatic HTLV-1 carriers in Kagoshima (HTLV-1 endemic area in Southern Japan) by using PCR-RFLP and subsequent direct sequencing analysis. All 272 subjects showed homozygosity in the CD45 exon 4, suggesting that this mutation is absent or very rare in Japanese population.

Design, synthesis, and characterization of a novel hemoprotein.

Here we describe a synthetic protein (6H7H) designed to bind four heme groups via bis-histidine axial ligation. The hemes are designed to bind perpendicular to another in an orientation that mimics the relative geometry of the two heme a groups in the active site of cytochrome c oxidase. Our newly developed protein-design program, called CORE, was implemented in the design of this novel hemoprotein. Heme titration studies resolved four distinct K(D) values (K(D1) = 80 nM, K(D2) = 18 nM, K(D3) > or = 3 mM, K(D4) < or = 570 nM, with K(D3) x K(D4) = 1700); positive cooperativity in binding between the first and second heme, as well as substantial positive cooperativity between the third and forth heme, was observed. Chemical and thermal denaturation studies reveal a stable protein with native-like properties. Visible circular dichroism spectroscopy of holo-6H7H indicates excitonic coupling between heme groups. Further electrochemical and spectroscopic characterization of the holo-protein support a structure that is consistent with the predefined target structure.

Secondary structure in lung surfactant SP-B peptides: IR and CD studies of bulk and monolayer phases.

Pulmonary surfactant protein SP-B is known to facilitate adsorption and spreading of surfactant components across the air/water interface. This property appears essential for in vivo function in the alveolar subphase and at the air/alveolar surface. Three peptides with amino acid sequences based on SP-B containing predicted alpha-helical regions (SP-B(1--20), SP-B(9--36A), SP-B(40--60A)) have been synthesized to probe structure-function relationships and protein-lipid interaction in bulk phase and monolayer environments. IR and CD studies are reported along with traditional surface pressure-molecular area (pi-A) isotherms and IR reflection-absorption spectroscopy (IRRAS) investigations conducted at the air/water interface. In bulk phase, helix-promoting environments (methanol and aqueous dispersions of lipid vesicles), SP-B(1--20) and SP-B(9--36A) contained significant amounts of alpha-helical structure, whereas varying degrees of alpha-helix, random coil, and beta-sheet were observed in aqueous solutions and monolayers. The most striking behavior was observed for SP-B(9--36A), which displayed reversible surface pressure-induced beta-sheet formation. Bulk phase lipid melting curves and monolayer experiments with peptide-lipid mixtures showed subtle differences in the degree of bulk phase interaction and substantial differences in peptide surface activity. The uniqueness of IRRAS is emphasized as the importance of evaluating secondary structure in both bulk phase and monolayer environments for lung surfactant peptide mimics is demonstrated.

Pycnogenol((R)) in the Management of Asthma.

Asthma is characterized as a chronic inflammatory process. Pycnogenol((R)), a bioflavonoid mixture extracted from Pinus maritima, is known to scavenge free radicals while possessing antioxidant and antiinflammatory properties. The objective of this study was to evaluate the efficiency of this agent in a randomized, double-blinded, placebo-controlled, crossover study in patients with varying asthma severity. Twenty-six patients who fulfilled the American Thoracic Society criteria for asthma were enrolled in the study. Medical history, physical examination, blood sample analyses, and spirometric values were obtained at baseline, 4 weeks, and 8 weeks. The patients were randomly assigned to receive either 1 mg/lb/day (maximum 200 mg/day) Pycnogenol or placebo for the first period of 4 weeks and then crossed over to the alternate regimen for the next 4 weeks. No adverse effects were observed related to the study drug. Within the contingent of 22 patients who completed the study, almost all responded favorably to Pycnogenol in contrast to placebo. Pycnogenol treatment also significantly reduced serum leukotrienes compared with placebo. The results of this pilot study indicate that Pycnogenol may be a valuable nutraceutical in the management of chronic asthma. We recommend that further clinical trials be conducted in larger groups of asthmatics to establish its efficacy.

A new approach to the design of uniquely folded thermally stable proteins.

A new computer program (CORE) is described that predicts core hydrophobic sequences of predetermined target protein structures. A novel scoring function is employed, which for the first time incorporates parameters directly correlated to free energies of unfolding (deltaGu), melting temperatures (Tm), and cooperativity. Metropolis-driven simulated annealing and low-temperature Monte Carlo sampling are used to optimize this score, generating sequences predicted to yield uniquely folded, stable proteins with cooperative unfolding transitions. The hydrophobic core residues of four natural proteins were predicted using CORE with the backbone structure and solvent exposed residues as input. In the two smaller proteins tested (Gbeta1, 11 core amino acids; 434 cro, 10 core amino acids), the native sequence was regenerated as well as the sequence of known thermally stable variants that exhibit cooperative denaturation transitions. Previously designed sequences of variants with lower thermal stability and weaker cooperativity were not predicted. In the two larger proteins tested (myoglobin, 32 core amino acids; methionine aminopeptidase, 63 core amino acids), sequences with corresponding side-chain conformations remarkably similar to that of native were predicted.