Surgery, stomas, and anxiety and depression in inflammatory bowel disease: a retrospective cohort analysis of privately insured patients.

AIM: Patients with inflammatory bowel disease (IBD) are diagnosed with anxiety/depression at higher rates than the general population. We aimed to determine the frequency of anxiety/depression among IBD patients and the temporal association with abdominal surgery and stoma formation. METHOD: We conducted a retrospective cohort study in adult patients with IBD using difference-in-difference methodology and a large commercial claims database (2003-2016). Outcomes were anxiety/depression diagnoses before and after major abdominal surgery or stoma formation. RESULTS: We identified 10 481 IBD patients who underwent major abdominal surgery, 18.8% of whom underwent stoma formation, and 41 924 nonsurgical age- and sex-matched IBD controls who were assigned random index dates. Rates of anxiety and depression increased among all cohorts (P < 0.001). Surgical patients had higher odds of anxiety [one surgery, adjusted OR 6.90 (95% CI 6.11-7.79), P < 0.001; two or more surgeries, 7.53 (5.99-9.46), P < 0.001] and depression [one surgery, 6.15 (5.57-6.80), P < 0.001; two or more surgeries, 6.88 (5.66-8.36), P < 0.001] than nonsurgical controls. Undergoing multiple surgeries was associated with a significant increase in depression from 'pre' to 'post' time periods [1.43 (1.18-1.73), P < 0.001]. Amongst surgical patients, stoma formation was independently associated with anxiety [1.40 (1.17-1.68), P < 0.001] and depression [1.23 (1.05-1.45), P = 0.01]. New ostomates experienced a greater increase in postoperative anxiety [1.24 (1.05-1.47), P = 0.01] and depression [1.19 (1.03-1.45), P = 0.01] than other surgical patients. CONCLUSION: IBD patients who undergo surgery have higher rates of anxiety and depression than nonsurgical patients. Rates of anxiety and depression increase following surgery. Stoma formation represents an additional risk factor. These findings suggest the need for perioperative psychosocial support services.

Deposition of zinc oxide as an electron transport layer in planar perovskite solar cells by spray and SILAR methods comparable with spin coating.

CH3NH3PbI3 planar-structure perovskite solar cells were fabricated with the configuration FTO/ZnO/CH3NH3PbI3/Au. ZnO nanoparticles were synthesized by the precipitation method. Three different deposition methods including spin-coating, spraying and successive ionic layer adsorption and reaction (SILAR) were applied to fabricate the ZnO films as electron transport layers. Certain analyses, such as XRD, SEM, FESEM, UV-visible and I-V measurements, were carried out to evaluate the performance of the cells. The best cell performance was achieved for the perovskite solar cell with a ZnO film coated by the spin method. The average efficiency was 7% without using any hole transport materials and 10.25% using spiro-OMeTAD as a hole transport material. The average efficiencies of the cells coated by the spraying and SILAR methods using spiro-OMeTAD, were found to be 8.64% and 7.7% respectively. This study demonstrates the versatility of the spray and SILAR coating methods and their potential for fabricating low-cost, large scale, flexible and mass produced perovskite solar cells.

Risk of post-operative surgical site infections after vedolizumab vs anti-tumour necrosis factor therapy: a propensity score matching analysis in inflammatory bowel disease.

BACKGROUND: Perioperative vedolizumab (VDZ) and anti-tumour necrosis factor (TNFi) therapies are implicated in causing post-operative complications in inflammatory bowel disease (IBD). AIM: To compare the risk of surgical site infections (SSIs) between VDZ- and TNFi-treated IBD patients in propensity-matched cohorts. METHODS: The Optum Research Database was used to identify IBD patients who received VDZ or TNFi within 30 days prior to abdominal surgery between January 2015 and December 2016. The date of IBD-related abdominal surgery was defined as the index date. SSIs were determined by ICD-9/10 and CPT codes related to superficial wound infections or deep organ space infections after surgery. Propensity score 1:1 matching established comparable cohorts based on VDZ or TNFi exposure before surgery based on evidence-based risk modifiers. RESULTS: The propensity-matched sample included 186 patients who received pre-operative biologic therapy (VDZ, n = 94; TNFi, n = 92). VDZ and TNFi cohorts were similar based on age, gender, IBD type, concomitant immunomodulator exposure, chronic opioid or corticosteroid therapy, Charlson Comorbidity Index and malnutrition. VDZ patients were more likely to undergo an open bowel resection with ostomy. After propensity score matching, there was no significant difference in post-operative SSIs (TNFi 12.0% vs VDZ 14.9%, P = 0.56). Multivariable analysis indicated that malnutrition was the sole risk factor for developing SSI (OR 3.1, 95% CI 1.11-8.71) regardless of the type of biologic exposure. CONCLUSION: In the largest, risk-adjusted cohort analysis to date, perioperative exposure to VDZ therapy was not associated with a significantly higher risk of developing an SSI compared to TNFi therapy.

Antibody-Mediated Osseous Regeneration for Bone Tissue Engineering in Canine Segmental Defects.

Among many applications of therapeutic monoclonal antibodies (mAbs), a unique approach for regenerative medicine has entailed antibody-mediated osseous regeneration (AMOR). In an effort to identify a clinically relevant model of craniofacial defect, the present study investigated the efficacy of mAb specific for bone morphogenetic protein- (BMP-) 2 to repair canine segmental mandibular continuity defect model. Accordingly, a 15 mm unilateral segmental defect was created in mandible and fixated with a titanium plate. Anorganic bovine bone mineral with 10% collagen (ABBM-C) was functionalized with 25 µg/mL of either chimeric anti-BMP-2 mAb or isotype-matched mAb (negative control). Recombinant human (rh) BMP-2 served as positive control. Morphometric analyses were performed on computed tomography (CT) and histologic images. Bone densities within healed defect sites at 12 weeks after surgery were 1360.81 ± 10.52 Hounsfield Unit (HU), 1044.27 ± 141.16 HU, and 839.45 ± 179.41 HU, in sites with implanted anti-BMP-2 mAb, rhBMP-2, and isotype mAb groups, respectively. Osteoid bone formation in anti-BMP-2 mAb (42.99% ± 8.67) and rhBMP-2 (48.97% ± 2.96) groups was not significantly different but was higher (p < 0.05) than in sites with isotype control mAb (26.8% ± 5.35). In view of the long-term objective of translational application of AMOR in humans, the results of the present study demonstrated the feasibility of AMOR in a large clinically relevant animal model.

The effect of a platelet-rich fibrin conduit on neurosensory recovery following inferior alveolar nerve lateralization: a preliminary clinical study.

This retrospective study aimed to assess the recovery of neurosensory dysfunction following modified inferior alveolar nerve (IAN) lateralization surgery compared to the conventional approach. Data from two groups of patients who underwent IAN lateralization in 2014 were included in this study. In one group, platelet-rich fibrin was placed over the IAN and this was protected with a collagen membrane conduit; the other group underwent the conventional IAN lateralization procedure. Implants were placed immediately. Neurosensory dysfunction was evaluated at 3, 6, and 12 months post-surgery. Demographic, neurosensory disturbance (NSD), subjective two-point discrimination test (TPD), and static light touch test (SLT) data were obtained. Twenty-three IAN lateralization procedures with the placement of 51 implants were performed in 14 patients. At the 6-month follow-up, the number of patients experiencing normal sensation was greater in the modified surgery group, but the 12-month follow-up results were the same in the two groups. More precise sensation was observed with the TPD in the modified group at 6 months, and the modified group demonstrated better SLT scores at 6 months. Although the two groups had comparable results at the 12-month follow-up, it was observed that the modified technique accelerated neural healing within 6 months and reduced the length of the discomfort period.

Prevalence and risk factors of diabetes mellitus in a central district in Islamic Republic of Iran: a population-based study on adults aged 40-80 years.

Previous studies on type 2 diabetes mellitus in the Islamic Republic of Iran were mainly performed in provinces with large populations. This study determined the prevalence and risk factors of diabetes mellitus in an adult population (40-80 years old) from Yazd district. Multistage, systematic cluster random sampling was used in a crosssectional, population-based survey. Demographic, clinical and anthropometric data were collected, with diabetes defined as fasting blood sugar ≥ 7 mmol/L or a positive medical history of diabetes. The age- and sex-standardized prevalence of diabetes in 2090 individuals participants was 24.5% (95% CI: 22.2-26.8%), including 10.5% new cases. For each year of ageing, the prevalence of diabetes increased significantly by 4% and this trend was more pronounced in females than males. Low education and hypertension were significantly associated with diabetes prevalence. The prevalence of diabetes mellitus in Yazd is greater than the average levels nationwide and those of nearby countries.

A GPU-implemented physics-based haptic simulator of tooth drilling.

BACKGROUND: Restorative dentistry simulation is one of the most challenging applications involving virtual reality and haptics. This paper presents a haptics-based tooth drilling simulator for dental education. METHODS: Unlike the existing methods, the force model is based on physical properties which consider the geometrical model of the tool. In order to provide uniform force feedback from tooth layers, a new approach is suggested in which the physical properties of each tooth voxel are subsequently used in calculating the feedback force. We implement a hashing algorithm for collision detection due to its reduced time complexity. The haptics algorithm has been implemented on a graphics processing unit using the CUDA toolbox. RESULTS: In parallel processing, the speed of haptic loop execution is increased almost 8 times. CONCLUSION: The proposed idea for force calculation leads to a uniform sensation of force. An important feature of the designed system is the capability to run in a real-time fashion.

The effect of butyric acid with autogenous omental graft on healing of experimental Achilles tendon injury in rabbits.

In this study, the role of local injection of butyric acid (BA) with autogenous omental graft was evaluated in healing of experimental Achilles tendon injury in rabbits. Nine adult male New Zealand rabbits were anesthetized and a partial thickness tenotomy was created on both hindlimbs. In treated group, omental graft was secured in place using BA soaked polygalactin 910 suture. In control group, the graft was sutured without BA. Butyric acid and normal saline were injected daily to treatment and control groups for three days, respectively. Based on the findings, on day 15 after injury, the tendon sections showed that healing rate in BA treated group was higher than that in control group. Furthermore, at days 28 and 45, comparison between BA treated and control groups demonstrated that BA increased the healing rate but with no significance. In summary, results of this study show that application of BA with autogenous omental graft can improve healing process of damaged Achilles tendon.

Prevalence and risk factors of diabetes mellitus in a central district in Islamic Republic of Iran:a population-based study on adults aged 40-80 years

إن الدراسات السابقة عن السكري من النمط 2 في جمهورية إيران الإسلامية أجريت أساساً في مقاطعات ذات كثافة سكانية عالية. إن هذه الدراسة حددت مدى انتشار السكري وعوامل الخطورة المتعلقة به لدى السكان البالغين [تتراوح أعمارهم ما بين 40-80 سنة]في مقاطعة يزد. فقد استُخدم اعتيان عشوائي عنقودي منهجي متعدد المراحل في مسح سكاني مقطعي. وتم جمع البيانات السكانية والسريرية والأنثروبومترية [المتعلقة بالقياسات البشرية]، مع تعريف السكري بكون سكر دم الصيامي > 7 مليمول/لتر أو بوجود تاريخ طبي إيجابي للسكري. فكان انتشار السكري المعير بحسب العمر والجنس لدى 2090 فرداً مشاركاً 24.5% [%95 CI:22.2-26.8%]، بينها 10.5% حالات جديدة. كما لوحظ أن هناك زيادة ملحوظة في انتشار السكري مع تقدم العمر بلغت 4% لكل سنة، وكان هذا الاتجاه أكثر وضوحاً لدى الإناث منه لدى الذكور. وكان هناك ارتباط كبير بين تدني التعليم وارتفاع ضغط الدم وبين انتشار السكري. إن انتشار السكري في يزد أكبر من متوسط انتشاره على الصعيد الوطني وفي الدول المجاورة

Previous studies on type 2 diabetes mellitus in the Islamic Republic of Iran were mainly performed in provinces with large populations. This study determined the prevalence and risk factors of diabetes mellitus in an adult population (40–80 years old) from Yazd district. Multistage, systematic cluster random sampling was used in a crosssectional, population-based survey. Demographic, clinical and anthropometric data were collected, with diabetes defined as fasting blood sugar ≥ 7 mmol/L or a positive medical history of diabetes. The age- and sex-standardized prevalence of diabetes in 2090 individuals participants was 24.5% (95% CI: 22.2–26.8%), including 10.5% new cases. For each year of ageing, the prevalence of diabetes increased significantly by 4% and this trend was more pronounced in females than males. Low education and hypertension were significantly associated with diabetes prevalence. The prevalence of diabetes mellitus in Yazd is greater than the average levels nationwide and those of nearby countries.

Les études antérieures sur le diabète sucré de type 2 en République islamique d'Iran ont été principalement menées dans des provinces très peuplées. La présente étude a déterminé la prévalence et les facteurs de risque du diabète sucré dans une population d'adultes (40‑80 ans) du district de Yazd. Un échantillonnage en grappes aléatoire et systématique à plusieurs degrés a été utilisé dans une enquête populationnelle transversale. Des données démographiques, cliniques et anthropométriques ont été recueillies, tandis que le diabète a été défini par un taux de glycémie supérieur ou égal à 7 mmol/L ou par des antécédents médicaux positifs pour la maladie. La prévalence du diabète normalisée pour l'âge et le sexe chez 2090 participants était de 24,5 % (IC à 95 % : 22,2–26,8 %), avec 10,5 % de nouveaux cas. Pour chaque année supplémentaire de vieillissement, la prévalencedu diabète augmentait de 4 % et cette tendance était davantage marquée chez les femmes que chez les hommes. Un faible niveau d'études et une hypertension étaient significativement associés à la prévalence du diabète. La prévalence du diabète sucré à Yazd est supérieure aux niveaux moyens à l'échelle nationale et dans les pays voisins.

Investigation of treatment options to minimize the effects of acid erosion on enamel.

This in vitro study investigated 4 products (containing calcium, phosphate, and/or fluoride) and their ability to reharden enamel softened by hydrochloric acid as compared to hardening with saliva alone. Extracted human molars were embedded and polished, and baseline Vickers hardness (VH) of enamel was measured. Statistical analysis was performed with ANOVA followed by Student-Newman-Keuls post hoc tests (P = 0.05). For all groups, VH decreased significantly after immersion in hydrochloric acid. Fluoride in combination with casein phosphopeptide amorphous calcium phosphate was the most effective treatment for enamel hardness recovery.

Orthopaedic nurses' knowledge about pressure ulcers in Iran: a cross-sectional study.

OBJECTIVE: To assess nurses' knowledge about pressure ulcers in an Iranian orthopaedic ward. METHOD: A cross-sectional, self-report questionnaire study using Pieper's Pressure Ulcer Knowledge Test (PUKT). Orthopaedic nurses' knowledge about pressure ulcers was examined in two teaching hospitals in Iran. The questionnaire consisted of 41 true or false assertions, categorised according to pressure ulcer classification and onset, wound characteristics and preventive measure. RESULTS: Of 68 nurses, 57 participated in this study (response rate of 84%); of the respondents, 68%(n=39) were women and 32% (n= 18) were men. Mean age of participants was 30.2 ± 5.1 years and mean years of experience was 6.9 ± 4.6 years. The overall rate of correct responses by nurses was 70.1%.Nurses had the highest level of knowledge in the pressure ulcer prevention category and the lowest in the pressure ulcer categorisation and onset section. No relationship was found between level of knowledge and nurses' years of experience. CONCLUSION: Pressure ulcer prevention is one of the most important roles of nurses in an orthopaedic setting. The results of this study suggest that orthopaedic nurses in Iran were not sufficiently knowledgeable about pressure ulcers. Therefore, there is a need to improve their knowledge with some targeted, educational programmes.

Retinal vessel abnormalities predict coronary artery diseases.

BACKGROUND: There are limited data supporting an association between retinal microvascular changes and cardiovascular mortality, but there is no convincing evidence of an independent or direct association with atherosclerosis in coronary artery disease (CAD) patients. The present study examines the relationship between retinal microvascular changes and angiographic findings. METHODS: Patients who were candidates for angiography were, at first, referred to the ophthalmology department for the determination of the severity of retinal atherosclerosis based on the Scheie classification. Angiography was carried out afterwards. Each patient completed a questionnaire, also providing information on risk factors. For each patient, the Gensini score was calculated using angiography findings. RESULTS: A total of 168 patients (99 males and 69 females) with a mean age of 55.3±11.9 years were included in this study. The results show a significant association between CAD severity and retinal artery atherosclerosis (r = 0.47, p = 0.0001). In multiple regression analyses with CAD severity (using Gensini scoring) as a dependent variable, we observed a significant association between atherosclerosis scores based on Scheie criteria (ß=0.31, p<0.0001), diabetes mellitus (DM) (ß=0.29, p<0.0001), hypertension (ß=0.23, p<0.0001), smoking (ß=0.20, p<0.0001), and age (ß=0.15, p<0.0001). CONCLUSIONS: The results demonstrate that fundoscopic changes might be a predictor of CADs. However, more well-designed studies to verify these results are still needed.

Histone deacetylases as targets for multiple diseases.

Inhibition of Histone deacetylases (HDACs) has been emerged as important approach to reverse aberrant epigenetic changes associated with various cancerous and non-cancerous diseases. The field of histone deacetylase inhibitors (HDIs) is moving into a new phase of development. The structure of histone deacetylases is well-established and the active sites have been well identified. Various drugs targeting this enzyme are in the pipeline for the treatment of different diseases. Since first-generation HDAC inhibitors proved their clinical fruitfulness and also second generation inhibitors are rationally designed with improved specificity, experts believe that this class will emerge in the treatment of various diseases. Considering these facts present review focuses on HDACs and developments of HDIs in the treatment of various diseases.

Estimation of Amlodipine Besylate, Valsartan and Hydrochlorothiazide in Bulk Mixture and Tablet by UV Spectrophotometry.

A simple, precise, accurate and economic simultaneous UV spectrophotometric method has been developed for the estimation of amlodipine besylate, valsartan and hydrochlorothiazide in combination in bulk mixture and tablet. The estimation was based upon measurement of absorbance at absorbance maxima of 359 nm, 317 nm and 250 nm for amlodipine besylate, hydrochlorothiazide and valsartan in methanol, respectively in bulk mixture and tablet. The Beer Lambert's law obeyed in the concentration range 5-25 µg/ml, 10-50 µg/ml and 5-25 µg/ml for amlodipine besylate, hydrochlorothiazide and valsartan, respectively. The estimation of bulk mixture and tablet was carried out by simultaneous equation, Q-analysis and area under curve method for estimation of amlodipine besylate and hydrochlorothiazide and standard curve method for estimation of valsartan. The results were found to be in the range of 99.6±1.52% to 102±0.51%. Method was validated with respect to specificity, linearity, range, accuracy, precision, LOD, LOQ, robustness, ruggedness and can be applied for routine analysis of tablet dosage forms.

Evaluation of the Effect of Plasma Rich in Growth Factors (PRGF) on Bone Regeneration.

OBJECTIVE: Reconstruction methods are an essential prerequisite for functional rehabilitation of the stomatognathic system. Plasma rich in growth factors (PRGF) offers a new and potentially useful adjunct to bone substitute materials in bone reconstructive surgery. This study was carried out to investigate the influence of PRGF and fibrin membrane on regeneration of bony defects with and without deproteinized bovine bone mineral (DBBM) on rabbit calvaria. MATERIALS AND METHODS: Twelve New Zealand white rabbits were included in this randomized, blinded, prospective study. Four equal 3.3×6.6 mm cranial bone defects were created and immediately grafted with DBBM, PRGF+DBBM, PRGF+fibrin membrane and no treatment as control. The defects were evaluated with histologic and histomorphometric analysis performed 4 and 8 weeks later. RESULTS: Adding PRGF to DBBM led to increased bone formation as compared with the control group in 4- and 8-week intervals. In DBBM and PRGF+fibrin membrane samples, no significant increase was seen compared to the control group. There was also a significant increase in the rate of biodegradation of DBBM particles with the addition of PRGF in the 8-week interval. Neither noticeable foreign body reaction nor any severe inflammation was seen in each of the specimens evaluated. CONCLUSION: Under the limitation of this study, adding PRGF to DBBM enhanced osteogenesis in rabbit calvarias. Applying autologous fibrin membrane in the defects was not helpful.

Development, reproducibility and validity of the food frequency questionnaire in the Poland arm of the Prospective Urban and Rural Epidemiological (PURE) study.

BACKGROUND: A food frequency questionnaire (FFQ) is the most commonly used method in large epidemiological studies. The validation of an FFQ is essential for specific populations because foods are culture-dependent. The present study aimed to develop an FFQ and evaluate its validity and reproducibility in estimating the intake of nutrients in urban and rural areas of Poland. METHODS: Adult participants (n = 146) in the Polish arm of the ongoing Prospective Urban and Rural Epidemiological (PURE) study completed FFQs on two occasions, as well as four 24-h dietary recalls (DRs) during a 12-month period. Correlation coefficients (r) and de-attenuated correlation coefficients between dietary recalls and both FFQs were calculated for selected macro- and micronutrients. Agreement between the two methods was evaluated by classification into quartiles and the Bland-Altman method. Reproducibility was assessed by the intra-class correlation coefficient (ICC). RESULTS: The final food list contained 134 food items. For urban participants, FFQ2 generally underestimated energy, protein and fat compared to the FFQ1 and mean of DRs. In rural areas, compared to DRs, both FFQs overestimated energy and macronutrients. For both urban and rural settings, de-attenuated correlation exceeded 0.4 for almost all nutrients and the exact agreement in quartile categorisation was >66%. When assessing repeatability, ICC varied from 0.39-0.63 in an urban setting and 0.19-0.45 in a rural setting. CONCLUSIONS: This 134-item FFQ has good validity and reproducibility in relation to the reference method and can be used to rank individuals based on their macro- and micronutrient intake.

Factors associated with fruit and vegetable consumption among adults.

BACKGROUND: The higher consumption of fruit and vegetables is considered to be an indicator of healthy eating and the protective effects of fruit and vegetable (FV) consumption for noncommunicable diseases have been investigated extensively. The present study aimed to investigate the association between fruit and vegetable intake (FVI), health behaviours and socio-demographic factors among adult Canadians. METHODS: This analysis was based on the information from the Canadian Community Health Survey, Cycle 3.1. Daily intake of fruit and vegetables from a total number of 15,512 apparently healthy individuals, aged 18-64 years, were assessed using a structured questionnaire, which included 20 questions on the frequency of consumption of different types of fruit and vegetables. Multiple logistic regression models were used to determine the association between FVI and some socio-economic factors and lifestyle behaviour among adult Canadians. RESULTS: In total 77% of Canadian adults consumed fruit and vegetables less than five times per day. Females were more likely to consume more fruit [odds ratio (OR) 2.05; 95% confidence interval (CI) 1.75-2.4], vegetables (OR 1.95; 95% CI 1.65-2.29) and FV (OR 2.52; 95% CI 2.20-2.90) than males. Single/never married individuals, individuals with higher levels of education, never smokers, former drinkers and older people reported more consumption of fruit and vegetables than others. CONCLUSIONS: The results obtained in the present study indicate an association between FVI and some socio-economic and healthy lifestyle behaviours, and that a substantial gap exists between the recommended level and the actual intake of the FV among the Canadian population. Because a higher intake of FV improves public health, it is imperative to tailor nutrition education at the individual and community levels in Canadian populations.

Isolation and differentiation of mesenchymal stem cells from bovine umbilical cord blood.

Currently, mesenchymal stem cells (MSCs) are used in veterinary clinical applications. Bone marrow and adipose tissue are the most common sources of stem cells derived from adult animals. However, cord blood which is collected non-invasively is an alternative source of stem cells other than bone marrow and adipose tissue. Moreover, high availability and lower immunogenicity of umbilical cord blood (UCB) haematopoietic stem cells compared to other sources of stem cell therapy such as bone marrow have made them a considerable source for cell therapy, but MSCs is not highly available in cord blood and their immunogenicity is poorly understood. In this study, the cells with spindle morphology from 7 of 9 bovine UCB samples were isolated and cultured. These mesenchymal stromal cells were successfully differentiated to osteocytes, chondrocytes and adipocytes. In addition, Oct-4 and SH3 were determined by RT-PCR assay. It is the first report of isolation, culture, characterization and differentiation of bovine umbilical stem cells.

Preparation of a novel floating ring capsule-type dosage form for stomach specific delivery.

Study objectives were to develop a unique floating ring capsule dosage form which combines gastric soluble and insoluble portions, and to evaluate its suitability for stomach specific drug delivery. New floating ring capsules were developed using different polymers and were compared for various parameters. The formulation with HPMC and sodium CMC has better floating properties. The effects of polymers concentration on drug release were studies by in vitro release studies. The interaction studies of combined drug with polymers were determined using FT-IR spectroscopy. The entrapped air within the gel barrier and lower densities of HPMC and sodium CMC resulted in better floating behavior. Steady slow gel formations showed prolonged drug release. The in vitro release rates were generally found to be faster with low concentration of carbopol showing release within 2 h, while formulations containing high amount of HPMC showed release in 8 h. In particular, the higher concentration of HPMC formulation shows the best drug release performance. A very low change in peak shift was observed only with sodium alginate formulations. Further, FT-IR measurements confirmed the absence of any chemical interactions. Results indicate that new floating ring capsule is a promise dosage form for stomach specific delivery.

Stomatal vs. genome size in angiosperms: the somatic tail wagging the genomic dog?

BACKGROUND AND AIMS: Genome size is a function, and the product, of cell volume. As such it is contingent on ecological circumstance. The nature of 'this ecological circumstance' is, however, hotly debated. Here, we investigate for angiosperms whether stomatal size may be this 'missing link': the primary determinant of genome size. Stomata are crucial for photosynthesis and their size affects functional efficiency. METHODS: Stomatal and leaf characteristics were measured for 1442 species from Argentina, Iran, Spain and the UK and, using PCA, some emergent ecological and taxonomic patterns identified. Subsequently, an assessment of the relationship between genome-size values obtained from the Plant DNA C-values database and measurements of stomatal size was carried out. KEY RESULTS: Stomatal size is an ecologically important attribute. It varies with life-history (woody species < herbaceous species < vernal geophytes) and contributes to ecologically and physiologically important axes of leaf specialization. Moreover, it is positively correlated with genome size across a wide range of major taxa. CONCLUSIONS: Stomatal size predicts genome size within angiosperms. Correlation is not, however, proof of causality and here our interpretation is hampered by unexpected deficiencies in the scientific literature. Firstly, there are discrepancies between our own observations and established ideas about the ecological significance of stomatal size; very large stomata, theoretically facilitating photosynthesis in deep shade, were, in this study (and in other studies), primarily associated with vernal geophytes of unshaded habitats. Secondly, the lower size limit at which stomata can function efficiently, and the ecological circumstances under which these minute stomata might occur, have not been satisfactorally resolved. Thus, our hypothesis, that the optimization of stomatal size for functional efficiency is a major ecological determinant of genome size, remains unproven.