Explorations of novel pyridine-pyrimidine hybrid phosphonate derivatives as aurora kinase inhibitors.

For developing novel therapeutic agents with good anticancer activities, a series of novel pyridine-pyrimidine hybrid phosphonate derivatives4(a-q) were synthesized by the Kabachnik-Fields method using CAN as catalyst. The compound 4o exhibited the most potent anticancer activity with an IC50 value of 13.62 µM, 17.49 µM, 5.81 µM, 1.59 µM and 2.11 µM against selected cancer cell lines A549, Hep-G2, HeLa, MCF-7, and HL-60, respectively. Compound 4o displayed seven times more selectivity towards Hep-G2 cancer cell lines compared to the human normal hepatocyte cell line LO2 (IC50 value 95.33 µM). Structure-Activity Relationship (SAR) studies were conducted on the variation in the aromatic ring (five-membered heterocyclic ring, six-membered heterocyclic ring) and the variation of substituents on the phenyl ring (electron donating groups, electron withdrawing groups). Furthermore, the mechanism of anticancer activity was clarified by further explorations in bioactivity by using in vitro aurora kinase inhibitory activity and molecular docking studies. The results showed that the compound 4o at IC50concentrationdemonstrated distinctive morphological changes such as cell detachment, cell wall deformation, cell shrinkage and reduced number of viable cells in cancer cell lines. Compound 4o induced early apoptosis and late apoptosis of 27.7% and 6.1% respectively.

Helicobacter pylori and cardiovascular complications: a mechanism based review on role of Helicobacter pylori in cardiovascular diseases.

Heart disease comprises a wide class of cardiovascular abnormalities, including ischemic heart disease, myocardial infarction, atherosclerosis, and coronary artery disease. It is the leading cause of death all over the world. Several traditional and novel risk factors, such as infectious and noninfectious agents, have been associated with heart disease. Out of these, Helicobacter pylori has been recently introduced as an important etiological factor for heart disease. Numerous seroepidemiological findings observed H. pylori antibodies in the blood of a patient with cardiovascular complications. The bacteria survive in the epithelial cells of gastric organs and cause digestive complications. Excess inflammatory pathogenesis and prognosis stimulate an immune response that further causes significant disturbances in various factors like cytokines, fibrinogen, triglycerides, high density lipoprotein, C-reactive protein, heat shock protein, and white blood cell count, and provoke a number of problems such as atherosclerosis and prothrombic state, and cross-reactivity which eventually leads to heart diseases. H. pylori releases toxigenic nutrients, chiefly vacuolating cytotoxin gen A (Vac A) and cytotoxin associated gene A (Cag A), of which Cag A is more virulent and involved in the formation of cholesterol patches in arteries, induction of autoimmune disorder, and release of immune mediated response. Although numerous mechanisms have been correlated with H. pylori and heart disease, the exact role of bacteria is still ambiguous.

Fabrication of fenofibrate nanocrystals by probe sonication method for enhancement of dissolution rate and oral bioavailability.

Fenofibrate (FBT) is lipophillic drug used in hypercholesterolemia and hypertriglyceridemia having logP 5.375, low solubility (practically insoluble in water) and low oral bioavailability (36%). The purpose of work was to develop FBT nanocrystals for the enhancement of solubility and oral bioavailability. Fenofibrate nanosuspension was prepared using probe sonicator and transformed into dry powder using freeze drying and characterized by DSC, FTIR, XRPD, SEM, particle size, polydispersity index (PDI), zeta potential, solubility, in vitro dissolution, in vivo bioavailability and stability studies. Formulation FNS3 and pure drug exhibited the in vitro dissolution about 73.89% and 8.53% in 1% sodium lauryl sulfate (SLS) media, respectively. When the particle size reduced from 80,000±923nm to 460±20nm, saturation solubility was significantly increased. The saturation solubility of formulation FNS3 in 0.5% and 1% of SLS media found to be 67.51±1.5µg/mL and 107±1.9µg/mL, respectively. While, the saturation solubility of pure drug in 0.5% and 1% of SLS was found to be 6.02±1.51µg/ml and 23.54±1.54µg/ml, respectively. The pharmacokinetic study of optimized nanocrystals (FNS3) conducted in New Zealand white rabbits showed 4.73-fold increase in relative bioavailability than that of pure drug. Long term stability studies showed that there was no significant change in the mean particle size and PDI at 5°C±3°C after 180 days. This enhanced dissolution and bioavailability of fenofibrate nanocrystals could be the promising approach for oral delivery.

Oromucosal delivery of venlafaxine by linseed mucilage based gel: in vitro and in vivo evaluation in rabbits.

Linseed is the crop that is used as a foodstuff in European and Asian countries. The objective of the present work was to extract mucilage from linseed, utilize it as mucoadhesive gelling agent along with synthetic polymers and administration of venlafaxine by buccal route in the gel form. Buccal administration of venlafaxine will avoid first pass metabolism, which will increase the bioavailability of the drug. Linseed mucilage based buccal mucoadhesive gel preparations in combination with chitosan, carbopol 934P, carboxy methylcellulose and polyvinyl pyrrolidone were formulated and the viscosity, gel strength, percentage mucoadhesion and in vitro diffusion of the formulation was evaluated. Formulation (F2) was subjected to in vivo analysis in rabbits. Formulation F2, which contained linseed mucilage (2 %) and chitosan (0.5 %), showed the highest percentage of mucoadhesion, gel strength and sustained drug diffusion. The bioavailability by the oral route and buccal route were compared with that of the intravenous route. The bioavailability of venlafaxine in the formulation F2 was 63.08 ± 1.28 % by buccal route, which was higher than by the oral route (39.21 ± 6.18 %). Based on these results, the combination of linseed mucilage and chitosan can be used to form a buccal mucoadhesive gel and increase the bioavailability of venlafaxine.

In vitro and in vivo consideration of novel environmentally responsive ophthalmic drug delivery system.

In the present study, novel environmentally responsive ophthalmic drug delivery system composed of two gelling polymers with different phase transition mechanisms was developed in order to obtain sustained drug release in ocular cavity. Combination of polyacrylic acid (carbopol 934P) and xanthan gum was investigated as ophthalmic vehicle and assessed for its in vitro and in vivo performance. Different ratios of these polymers were used to prepare environmentally responsive ophthalmic drug delivery system by simple mixing procedure. Developed formulation was assessed for physical tests such as appearance/clarity, pH, gelation; and performance characteristics such as drug content, rheological measurement, in vitro release, antimicrobial efficiency, in vivo studies for eye irritation, residence time estimation. Prepared formulation showed agreeable appearance/clarity, acceptable pH and good gelation property. In vitro and in vivo studies demonstrated adequate drug content, desired rheological behavior and reasonable in vitro and in vivo drug release property. In conclusion, the optimum concentration of polymers results in increased residence time and sustained drug release. On the basis of these findings, environmentally responsive system based on combination of carbopol and xanthan gum may be considered as a promising tool for ophthalmic delivery.

Microwave-generated bionanocomposites for solubility and dissolution enhancement of poorly water-soluble drug glipizide: in-vitro and in-vivo studies.

OBJECTIVES: In oral absorption of a drug, the drug first dissolves and then is absorbed by diffusion through gastrointestinal membranes. The gastrointestinal environment is aqueous in nature and it is well-known that one-third of the drug population is water insoluble. Hence, there is a need for enhancement of the solubility and dissolution of such drugs. In this work, enhancement of the solubility and dissolution of the practically insoluble drug glipizide was achieved by formation of bionanocomposites (BNCs) using microwave-induced diffusion (MIND), which ultimately leads to bioavailability enhancement. METHODS: BNCs were formed by using natural carriers such as gelatin, acacia, cassia and ghatti gum, with the help of microwaves. Selection of carriers was based on their surfactant and wetting properties. Solubility studies were carried out to establish the solubility-enhancing property of the BNCs. To support solubility analysis results, dissolution studies (i.e. powder dissolution and in-vitro dissolution) were carried out. The BNCs were characterized by Fourier transform infra-red spectroscopy, differential scanning calorimetry, X-ray diffraction studies, scanning electron microscopy and transmission electron microscopy. In-vivo performance of the optimised formulation was assessed by glucose-induced hyperglycaemia test in male albino Wistar rats. KEY FINDINGS: It was found that as the concentration of polymer in the composite increased the solubility and dissolution of glipizide were enhanced. The optimised ratio (drug : polymer) for all the composites was found to be 1:9. In the glucose-induced hyperglycemia test in rats, the optimized formulation demonstrated a significant reduction in hyperglycemia compared with a marketed formulation, Glynase. CONCLUSIONS: The novelty of this work is the green and cost-effective way of forming drug nanocomposites with the help of microwave, which can be scaled up to an industrial level. The method gives an immaculate means of solubilisation by generating drug dispersion at the micro and nanoscale level in natural biodegradable stabilising media. Hence, this study demonstrates the use of BNCs in solubility and dissolution enhancement.

Design and in vitro and in vivo characterization of mucoadhesive matrix pellets of metformin hydrochloride for oral controlled release: a technical note.

The aim of the current work was to design and develop matrix pellets of hydroxy propyl methyl cellulose K200M and microcrystalline cellulose in an admixture for a mucoadhesive gastroretentive drug delivery system. Pellets containing metformin hydrochloride (500 mg) were prepared by the pelletization technique using an extruder-spheronizer. Pellets were characterized by differential scanning calorimetry (DSC), x-ray diffraction (XRD), scanning electron microscopy (SEM), circularity, roundness, percent drug content, percent production yield, in vitro swelling, ex vivo mucoadhesion, in vitro drug release and in vivo x-ray imaging studies. Optimized pellets were sufficiently porous spheroids, free flowing, had smooth surfaces, had yields up to 75.45 ± 0.52% and had drug content up to 96.45 ± 0.19%. The average particle size of formulations MF2 and MF6 were 1.13 ± 0.41 mm and 1.22 ± 0.18 mm, respectively. Formulation MF6 exhibited strong adhesion, about 94.67%, to goat mucosal tissue, and the desired in vitro swelling, with a sustained drug release profile for 12 h and with retention in the upper small intestine of rabbits for 10 h. We conclude that hydroxy propyl methyl cellulose K200M and microcrystalline cellulose at a 2.80:1.00 w/w ratio could be an effective carrier for multiple unit controlled delivery of metformin hydrochloride.

Formulation and evaluation of bilayer tablets of metoclopramide hydrochloride and diclofenac sodium.

The main objective of the present research work was to develop a bilayer tablet of metoclopramide hydrochloride (MTH) and diclofenac sodium (DS) in separate layers to avoid incompatibility and thus to maximize the efficacy of both drugs in combination for the effective treatment of migraine headaches. MTH and DS were formulated as immediate and sustained release layers respectively. In vitro dissolution kinetic studies of an optimized (D10) batch of DS in both sustained release layer and bilayer tablet forms show good linearity of regression coefficient 0.9773 (first order equation). The results reveal that an optimized immediate release layer (M5) of MTH and a sustained release layer (D10) of DS might be suitable for the treatment of migraine by sequential release of the two drugs in a bilayer tablet. LAY ABSTRACT: Migraine is a type of recurring headache of moderate to severe intensity associated with gastrointestinal, neurological, and autonomic symptoms. In migraine, a combination of pretreatment with antiemetics is required for symptomatic treatment, when nausea and vomiting are severe. In our present research, we have selected the metoclopramide hydrochloride (MTH) active ingredient for study because it has an antiemetic effect and is a prokinetic agent. MTH is more effective to counteract gastric stasis associated with migraine, and it enhances the rate of absorption of non-steroidal anti-inflammatory drugs (NSAIDs). In the present investigation we combine MTH and a second active ingredient, diclofenac sodium, as a formulated bilayer tablet to prevent degradation of MTH.

Identification and development of 2,5-disubstituted oxadiazole as potential candidate for treatment of XDR and MDR tuberculosis.

Tuberculosis, the infection on the verge of eradication once, is now a great threat to mankind. Emergence of MDR and XDR-TB synergised with HIV and other immune-compressive diseases have increased the life threatening capacities of the disease. A small molecule has been identified here, which showed potent anti-tubercular activity. The identified hit compound has also been proved active against nearly 25 clinical isolates comparable with isoniazid.

Cress seed mucilage based buccal mucoadhesive gel of venlafaxine: in vivo, in vitro evaluation.

Venlafaxine is a newer antipsychotic drug which shows first pass effect. Cress seed is also called as garden cress or green salad. This study examined the mechanical (gel strength, adhesiveness) and rheological properties of cress seed mucilage based gels that contain different ratios of carbopol 934 P (0.5-1.5%). In addition, diffusion of venlafaxine from gel formulations was evaluated. The selected formulation was further analyzed for pharmacokinetic parameters in rabbits. All formulations exhibited pseudoplastic flow with thixotropy. Formulation F5 showed the C(max) of 24.19 ± 0.72 ng/ml by buccal route of administration and 17.98 ± 1.15 ng/ml by oral route of administration. The bioavailability of F5 by buccal route was 54.44% and that of by oral route was 39.60%. A combination of the cress seed mucilage and carbopol 934 P resulted in a prolonged and higher venlafaxine delivery by buccal route of administration.

A novel hydrogel plug of Sterculia urens for pulsatile delivery: in vitro and in vivo evaluation.

The objective of this study was to investigate a novel hydrogel plug using isolated root mucilage of Sterculia urens to obtain a desired lag time for an oral chronotherapeutic colon-specific pulsatile drug delivery of indomethacin. Pulsatile drug delivery was developed using chemically treated hard gelatin capsule bodies filled with eudragit multiparticulates of indomethacin, and sealed with different hydrogel plugs (root mucilage of S. urens, xanthan gum, guar gum, HPMC K4M and combination of maltodextrin with guar gum). Indomethacin multiparticulates were prepared using extrusion spheronization, spray drying and solvent evaporation techniques with Eudragit® L-100 and S-100 (1:2) by varying drug-to-polymer ratio. After oral administration, the water-soluble cap of capsule dissolved in the intestinal fluid and the hydrogel plug swells. After a controlled time, the swollen plug subsequently ejected from the dosage form, releases the contents of the capsule. The formulation factors affecting the drug release were concentration and types of hydrogel plug used. In vivo gamma scintigraphy study in healthy rabbits proved the capability of the system to release drug in lower parts of the gastrointestinal tract after a programmed lag time. This study demonstrates that the indomethacin multiparticulates could be successfully colon-targeted by the design of time and pH-dependent modified chronopharmaceutical formulation. In conclusion, the investigated novel hydrogel plug could be a valuable tool for achieving desired lag time.

In vivo, in vitro evaluation of linseed mucilage based buccal mucoadhesive microspheres of venlafaxine.

The purpose of the present research work was to extract linseed mucilage, use it as a mucoadhesive agent and to develop mucoadhesive microspheres for buccal delivery with an intention to avoid hepatic first-pass metabolism, by enhancing residence time in the buccal cavity. Linseed mucilage was extracted and used to prepare microspheres with varying concentrations of mucilage from formulation F1-F4 (1-2.5%) by spray-drying technique. The microspheres were evaluated for the yield, particle size, incorporation efficiency, swelling property, in vitro mucoadhesion, in vitro drug release, histological study, and stability. Microspheres were characterized by differential scanning colorimetry, scanning electron microscopy, and X-ray diffraction study. Further, the bioavailability study using the New Zealand rabbits was carried out. Formulation F4 showed the maximum mucoadhesion 89.37 ± 1.35%, 92.10 ± 1.37% incorporation efficiency, highest swelling index 0.770 ± 1.23. F4 showed a marked increase in the bioavailability after buccal administration (51.86 ± 3.95) as compared to oral route (39.60 ± 6.16). Also it took less time to reach maximum plasma concentration of 21.38 ± 1.05 ng/ml as compared to oral solution where it required 180 min to reach maximum plasma concentration of 17.98 ± 1.14. It is concluded from the results that linseed mucilage can be used in the production of the mucoadhesive microspheres.

Enhancement of oral bioavailability of atorvastatin calcium by self-emulsifying drug delivery systems (SEDDS).

The aim of the present study was to formulate a self-emulsifying drug delivery system of atorvastatin calcium and its characterization including in vitro and in vivo potential. The solubility of atorvastatin calcium was determined in various vehicles such as Captex 355, Captex 355 EP/NF, Ethyl oleate, Capmul MCM, Capmul PG-8, Gelucire 44/14, Tween 80, Tween 20, and PEG 400. Pseudoternary phase diagrams were plotted on the basis of solubility data of drug in various components to evaluate the microemulsification region. Formulation development and screening was carried out based on results obtained from phase diagrams and characteristics of resultant microemulsion. Prepared formulations were tested for microemulsifying properties and evaluated for clarity, precipitation, viscosity determination, drug content and in vitro dissolution. The optimized formulation further evaluated for particle size distribution, zeta potential, stability studies and in vivo potential. In vivo performance of the optimized formulation was evaluated using a Triton-induced hypercholesterolemia model in male Albino Wistar rats. The formulation significantly reduced serum lipid levels as compared with atorvastatin calcium. Thus studies illustrated the potential use for the delivery of hydrophobic drug such as atorvastatin calcium by oral route.

Predictable pulsatile release of tramadol hydrochloride for chronotherapeutics of arthritis.

The present investigation deals with the development of a pH and time-dependent press-coated pulsatile drug delivery system for delivering drugs into the colon. The system consists of a drug containing core, coated by a combination of natural polymer Delonix regia gum (DRG) and hydroxypropyl methylcellulose (HPMC K4M) in various proportions, which controls the onset of release. The whole system was coated with methacrylic acid copolymers, which not only prevents the drug release in the stomach, but also prolongs the lag time. Tramadol HCl was used as a model drug and varying combinations of DRG and HPMC K4M were used to achieve the desired lag time before rapid and complete release of the drug in the colon. It was observed that the lag time depends on the coating ratio of DRG to HPMC and also on press coating weight. Drug release was found to be increased by 15-30% in the presence of colonic microbial flora. The results showed the capability of the system in achieving pulsatile release for a programmable period of time and pH-dependent release to attain colon-targeted delivery.

Floating-mucoadhesive beads of clarithromycin for the treatment of Helicobacter pylori infection.

An objective of the present study was to develop alginate/hydroxypropyl methylcellulose (HPMC) based floating-mucoadhesive beads of clarithromycin to provide prolonged contact time of antibiotic to treat stomach ulcer. Floating-mucoadhesive beads were prepared and characterized for in vitro performance followed by investigation of ex vivo study in albino-wistar rats. Beads were prepared by ionic gelation technique where calcium chloride used as gelating agent and incorporated liquid paraffin for floating of the beads. Prepared beads were evaluated extensively for particle size, drug entrapment; swelling and surface morphology by using scanning electron microscopy. X-ray radioimaging study in rabbits, in vitro mucoadhesion using rat stomach mucosal membrane and in vitro drug release studies were carried out. Ex vivo performance of alginate-HPMC beads were studied using albino rats in comparison to simple alginate-calcium beads. Alginate-HPMC beads may be suitable floating-muco-adhesive drug delivery system for delivering clarithromycin to treat stomach ulcers.

Development of colon targeted multiparticulate pulsatile drug delivery system for treating nocturnal asthma.

The aim of the present study was to develop theophylline fast release enteric-coated pellets as a pulsatile drug delivery to the colon. The novelty of this work is the combination of pH and time-dependant enteric polymers as a single coating for the development of multiparticulate formulation. Theophylline pellets were optimized by applying a 2-factors 3-levels full factorial design. Continuous dissolution studies were carried out in simulated gastric, intestinal, and colonic fluid with pH 1.2 (0.1 N HCl), pH 7.4 and pH 6.8 (phosphate buffer), respectively. The lag time prior to the drug release was highly affected by combination of two factors, i.e. the percentage of Eudragit RL100 in polymer mixture and coating level. The formulation containing Eudragit RL100 and Eudragit S100 with a ratio of 4:1 and coating level of 12%w/w was found to be optimum. The results of serum study in New Zealand rabbits showed that the developed formulation provided a significant lag phase of 5 h. The present study demonstrates that the theophylline enteric-coated pellets could be successfully colon targeted by the design of pH- and time-dependant modified chronopharmaceutical formulation. In conclusion, pulsatile drug release over a period of 3-12 h is consistent with the requirements for chronopharmaceutical drug delivery.

Rapidly disintegrating tablets containing taste masked metoclopramide hydrochloride prepared by extrusion-precipitation method.

The purpose of this study was to mask the intensely bitter taste of metoclopramide HCl and to formulate a rapid disintegrating tablet (RDT) of the taste-masked drug. Taste masking was done by complexing metoclopramide HCl with aminoalkyl methacrylate copolymer (Eudragit EPO) in different ratio by the extrusion-precipitation method. Drug-polymer complexes (DPCs) were tested for drug content, in vitro taste in simulated salivary fluid (SSF) of pH 6.8, taste evaluation in oral cavity and molecular property. The complex having drug-polymer ratio of 1 : 2 shows significant taste masking, confirmed by drug release in SSF and in-vivo taste evaluation; therefore, it was selected for further study. Taste evaluation of DPCs in human volunteers revealed considerable taste masking with the degree of bitterness below threshold value (0.5) within 10 s, whereas, metoclopramide HCl was rated intensely bitter with a score of +3 for 10 s. Tablets were evaluated for various parameters like tensile strength, wetting time, water absorption ratio, in-vitro disintegration time, and disintegration in oral cavity. The effect of diluents, lubricants and sweetening agent (Xylisorb) on the disintegration time was also evaluated. Tablets of batch F3 containing mannitol and microcrystalline cellulose in the ratio 1 : 1 and 8% w/w crosspovidone showed faster disintegration (within 20 s) than the marketed formulation (180 s). Good correlation between in vitro disintegration behavior and in the oral cavity was recognized. Tablets of batch F3 also revealed rapid drug release (t(90), 90 s) in SGF compared with marketed formulation (t(90), 600 s).

In situ gels of Metoclopramide Hydrochloride for intranasal delivery: in vitro evaluation and in vivo pharmacokinetic study in rabbits.

Intranasal (IN) administration is a promising approach for rapid-onset delivery of medications and to circumvent their first-pass elimination when taken orally. Metoclopramide Hydrochloride (MET HCl) is a potent antiemetic, effective even for preventing emesis induced by cancer chemotherapy. The feasibility of developing an efficacious intranasal formulation of metoclopramide has been undertaken in this study. Formulations were modulated so as to have gelation at physiological ion content after intranasal administration. Gelation was determined by physical appearance. The mucoadhesive force in terms of detachment stress, determined using sheep nasal mucosal membrane, increased with increasing concentration of carbopol. The results of in vitro drug permeation studies across sheep nasal mucosa indicate that effective permeation could be significantly increased by using in situ gelling formulation with carbopol concentration 0.15% or greater. Histological examination did not detect any damage during in vitro permeation studies. Finally, the bioavailability study in rabbits revealed that the absolute bioavailability of MET HCl was significantly increased from 40.67% in the case of the oral drug solution to 54.61% in the case of the nasal in situ gel. This study points to the potential of mucoadhesive nasal in situ gel in terms of ease of administration, accuracy of dosing, prolonged nasal residence and improved drug bioavailability.

Development and evaluation of a pulsatile drug delivery system using novel polymer. Part II: in vivo radio imaging study.

The objective of the present study was to correlate the results of the in vitro release of a previously reported pulsatile drug delivery system with the in vivo radio imaging study. The formulated drug delivery system containing pellets of barium sulphate was administered to rabbits after overnight fast. Formulated dosage form, previously evaluated for in vitro drug release study, showed drug release after 6-10 h of lag time depending on the hardness as well as the thickness of the plug. Radio imaging study also showed that the plug in the capsule drug delivery system remains intact for the period of 6 h. Thus, the formulated drug delivery system is capable of delaying release in vitro as well as in rabbits for 6 hours.

Formulation and evaluation of floating, pulsatile, multiparticulates using pH-dependent swellable polymers.

The objective of this study was to develop a floating, pulsatile, multiparticulate drug delivery system intended for chronopharmacotherapy of arthritis. The floating pulsatile drug delivery has the advantage that a drug can be released in the upper gastrointestinal tract after a definite time period of no drug release, i.e. lag time. Cross-linked beads were prepared using low methoxylated pectin (LM104AS), sodium alginate, and low methoxylated pectin (LM104AS) along with sodium alginate by acid- base reaction during ionotropic gelation. Beads were dried in oven at 50 degrees C for 4 h. Aceclofenac was used as a model drug for encapsulation. Drug loaded multiparticulates were subjected to various characterization and evaluation parameters like entrapment efficiency, surface topography, size analysis and in vitro release study. It was found that calcium pectinate beads show maximum drug entrapment. Hence, pectin containing formulation was further studied for buoyancy, DSC and radio imaging study. Drug release study was performed in acidic environment using pH 1.2 buffer solution for 6 h and then at 7.4 pH for 60 min. The total drug release ranges from 5-10% and 90-94% in acidic and basic media, respectively.