Imaging Fibrogenesis in a Diet-Induced Model of Nonalcoholic Steatohepatitis (NASH).

Purpose: Liver fibrosis is the hallmark of chronic nonalcoholic steatohepatitis (NASH) and is characterised by the excessive deposition of extracellular matrix proteins. Early detection and accurate staging of liver fibrosis is critically important for patient management. One of the earliest pathological markers in NASH is the activation of hepatic stellate cells (HSCs) which may be exploited as a marker of fibrogenesis. Activated HSCs secreting factors such as integrin α v ß 3 propagate fibrosis. The purpose of the current study was to assess the utility of the integrin α v ß 3 imaging agent [18F]FtRGD for the early detection of fibrosis in a diet-induced model of NASH longitudinally using PET imaging. Procedures: Mice were fed with either standard chow diet (SD), high-fat diet (HFD), or a choline-deficient, L-amino acid-defined high-fat fibrogenic diet (CDAHFD) to mimic the clinical pathology of liver disease and followed longitudinally for 10 weeks to assess the development of liver fibrosis using [18F]FtRGD positron emission tomography (PET) imaging. Standard blood biochemistry, histological measures, and qPCR were used to quantify integrin α v ß 3, smooth muscle actin, and collagen types 1 and 6 to assess the extent of NASH pathology and accurately stage liver fibrosis. Results: The CDAHFD fibrogenic diet predictably developed hepatic inflammation and steatosis over the 10 weeks studied with little NASH pathology detected in high fat diet-treated animals. Stage 1 fibrosis was detected early by histology at day 21 and progressed to stage 2 by day 35 and stage 3 by day 56 in mice fed with CDAHFD diet only. Noninvasive imaging with [18F]FtRGD correlated well with integrin α v ß 3 and was able to distinguish early mild stage 2 fibrosis in CDAHFD animals compared with standard chow diet-fed animals at day 35. When compared with high fat diet-fed animals, [18F]FtRGD was only able to distinguish later moderate stage 2 fibrosis in CDAHFD animals at day 49. Conclusions: The diet-induced progression of liver fibrosis was confirmed using histology and correlated well with the mRNA of integrin α v ß 3 and extracellular matrix protein expression. [18F]FtRGD showed very good correlation between liver uptake and integrin α v ß 3 expression and similar detection sensitivity to the current clinical gold standard modalities for staging of liver fibrosis.

Imaging adipose tissue browning using the TSPO-18kDa tracer [18F]FEPPA.

OBJECTIVES: The browning of white adipose tissue (WAT) into beige has been proposed as a strategy to enhance energy expenditure to combat the growing epidemic of obesity. Research into browning strategies are hampered by the lack of sensitive, translatable, imaging tools capable of detecting beige fat mass non-invasively. [18F]FDG is able to detect activated beige fat but provides little information on unstimulated beige fat mass. We have assessed the use of [18F]FEPPA, a tracer for the TSPO-18KDa found on the outer mitochondrial membrane, as an alternative imaging agent capable of detecting unstimulated brown fat (BAT) and beige fat. METHODS: Female Balb/c mice (n = 5) were treated for 7 days with the ß3 adrenergic agonist CL-316,243 to induce the browning of inguinal WAT (beige fat). Animals were imaged longitudinally with [18F]FDG and [18F]FEPPA and uptake in interscapular BAT and inguinal WAT assessed. The browning of inguinal WAT was confirmed using H&E and immunohistochemical detection of UCP-1 and TSPO. RESULTS: Repeated dosing with ß3-adrenergic agonist CL-316,243 caused a significant increase in [18F]FDG uptake in both interscapular BAT and inguinal WAT associated with the increased metabolic activity of brown and beige adipocytes respectively. [18F]FEPPA uptake was likewise increased in inguinal WAT but showed no increase in BAT uptake due to stimulation over the same time course. Furthermore, inguinal WAT uptake was unaffected by pharmacological blockade, indicating that [18F]FEPPA uptake is associated with the expression of mitochondria in BAT and beige adipocytes and independent of activation. CONCLUSION: These data show that [18F]FEPPA can detect BAT and newly formed beige fat under non-stimulated, thermoneutral conditions and that uptake after stimulation is linked to mitochondrial expression as opposed to activation.

Imaging the Proangiogenic Effects of Cardiovascular Drugs in a Diabetic Model of Limb Ischemia.

Purpose: Peripheral artery disease (PAD) causes narrowing of arteries in the limbs, leading to tissue ischemia, gangrene, and eventually limb amputation. The presence of diabetes greatly exacerbates the course of PAD, accounting for the majority of lower limb amputations. Therapeutic strategies focussing on macrovascular repair are less effective in diabetic patients where smaller vessels are affected, and proangiogenic therapies offer a viable adjunct to improve vascularisation in these at risk individuals. The purpose of the current study was to assess the proangiogenic effects of drugs routinely used to treat cardiovascular disease in a diabetic murine model of hind limb ischemia longitudinally using multimodal imaging. Procedures: Diabetic mice underwent surgical intervention to induce hind limb ischemia and were treated with simvastatin, metformin, or a combination orally for 28 days and compared to diabetic and nondiabetic mice. Neovascularisation was assessed using [18F]FtRGD PET imaging, and macrovascular volume was assessed by quantitative time of flight MRI. At each imaging time point, VEGF expression and capillary vessel density were quantified using immunohistochemical analysis, and functional recovery and disease progression were assessed. Results: Combined use of simvastatin and metformin significantly increased neovascularisation above levels measured with either treatment alone. Early angiogenic events were accurately assessed using PET [18F]FtRGD, showing maximal retention in the ischemic hind limb by day 8, which translated to a sustained increase in vascular volume at later time points. Immunohistochemical analysis shows that combined therapy significantly increased VEGF expression and capillary density (CD31+) in a similar time course and also slowed disease progression while simultaneously improving functional foot use. Conclusions: Combined treatment with simvastatin and metformin led to a significant improvement in limb angiogenesis, vascular volume, and sustained functional recovery in a diabetic murine model of HLI. PET imaging with [18F]FtRGD provides a robust method for early detection of these proangiogenic effects preclinically and may be useful for the assessment of proangiogenic therapies used clinically to treat diabetic PAD patients.

Dry powder inhalers: study of the parameters influencing adhesion and dispersion of fluticasone propionate.

Interactions between particles are dependent on the physicochemical characteristics of the interacting particles but it is also important to consider the manufacturing process. Blending active pharmaceutical ingredient (API) with carrier is a critical stage that determines the blend homogeneity and is the first step towards obtaining the final quality of the powder blend. The aim of this work was to study parameters that influence the interactions between API and carrier in adhesive mixtures used in DPI and their effect on API dispersion. The study was done with fluticasone propionate blended with lactose 'Lactohale 200'. The study was based on the influence of the operating conditions (speed, mixing time, resting steps during mixing), the size of the carrier and the storage conditions on the blend properties and on the API dispersion. The quality of the blends was examined by analysing the API content uniformity. Adhesion characteristics were evaluated by submitting mixtures to a sieving action by air depression with the Alpine air-jet sieve. Aerodynamic evaluation of fine particle fraction (FPF) was obtained using a Twin Stage Impinger; the FPF being defined as the mass percentage of API below 6.4 µm. For good dispersion and therefore good homogeneity of the API in the carrier particles, speed and powder blending time have to be sufficient, but not too long to prevent the appearance of static electricity, which is not favourable to homogeneity and stability. The FPF increases with the decrease in the carrier size. The storage conditions have also to be taken into consideration. Higher humidity favours the adhesion of API on the carrier and decreases the FPF.

Agglomerate behaviour of fluticasone propionate within dry powder inhaler formulations.

Due to their small size, the respirable drug particles tend to form agglomerates which prevent flowing and aerosolisation. A carrier is used to be mixed with drug in one hand to facilitate the powder flow during manufacturing, in other hand to help the fluidisation upon patient inhalation. Depending on drug concentration, drug agglomerates can be formed in the mixture. The aim of this work was to study the agglomeration behaviour of fluticasone propionate (FP) within interactive mixtures for inhalation. The agglomerate phenomenon of fluticasone propionate after mixing with different fractions of lactose without fine particles of lactose (smaller than 32 µm) was demonstrated by the optical microscopy observation. A technique measuring the FP size in the mixture was developed, based on laser diffraction method. The FP agglomerate sizes were found to be in a linear correlation with the pore size of the carrier powder bed (R(2)=0.9382). The latter depends on the particle size distribution of carrier. This founding can explain the role of carrier size in de-agglomeration of drug particles in the mixture. Furthermore, it gives more structural information of interactive mixture for inhalation that can be used in the investigation of aerosolisation mechanism of powder. According to the manufacturing history, different batches of FP show different agglomeration intensities which can be detected by Spraytec, a new laser diffraction method for measuring aerodynamic size. After mixing with a carrier, Lactohale LH200, the most cohesive batch of FP, generates a lower fine particle fraction. It can be explained by the fact that agglomerates of fluticasone propionate with very large size was detected in the mixtures. By using silica-gel beads as ball-milling agent during the mixing process, the FP agglomerate size decreases accordingly to the quantity of mixing aid. The homogeneity and the aerodynamic performance of the mixtures are improved. The mixing aid based on ball-milling effect could be used to ameliorate the quality of inhalation mixture of cohesive drug, such as fluticasone propionate. However, there is a threshold where an optimal amount of mixing aids should be used. Not only the drug des-aggregation reaches its peak but the increase in drug-carrier adhesion due to high energy input should balance the de-agglomeration capacity of mixing process. This approach provides a potential alternative in DPI formulation processing.

Influence of the lactose grade within dry powder formulations of fluticasone propionate and terbutaline sulphate.

Dry powder formulations are often composed of fine drug particles and coarser carrier particles, typically alpha-lactose monohydrate. However, the performance of a powder formulation may be highly dependent on the lactose quality and source. This study investigated the characteristics of lactose that influence the drug-to-carrier interaction and the performance of lactose-based dry powder inhaler formulations. The selected lactoses differed in the preparation processes and the content of fine lactose particles. Efficiency testing was done using fluticasone propionate and terbutaline sulphate as model drugs. Inverse gas chromatography was used to determine the surface heterogeneity distribution of different energy sites of the lactose and to understand the mechanism by which the fine carrier particles can improve the performance of dry powder inhalers. To assess the adhesion of respirable-sized drug to carrier particles, a simple method was developed based on aspiration and considering the whole blend as it is used in dry powder inhalers. When the percentage of fine lactose is high, a lower quantity of drug adheres to the lactose and/or the adhesion force is also lower. This was confirmed by the aerosolization assays done in the TSI (twin stage impinger). A correlation was observed between adhesion characteristics and inertial impaction. For both drugs, the fine particle fractions were highest in blends that present a greater proportion of lactose fine particles. A fairly good correlation between the fine particle fractions of both drugs and the peak max value and the AUC (area under curve) were found by inverse gas chromatography. With higher fine particle fraction values, which correspond to higher content of fines, the peak maxima determined by inverse gas chromatography were shifted to higher adsorption potentials, which supports the agglomeration hypothesis.

In vitro evaluation of powders for inhalation: the effect of drug concentration on particle detachment.

Limited information on the effect of the drug concentration on the performance of powders for inhalation is currently published. The aim of this work was to study the influence of drug concentration on the adhesion between drug and carrier and on the drug detachment from the carrier. The study was done with formoterol fumarate and fluticasone propionate blended with lactose Lactohale 200. To assess the adhesion of respirable-sized drug to carrier particles, a simple method was developed based on aspiration and considering the whole blend as it is used in dry powder inhalers. Adhesion characteristics were evaluated by submitting the mixtures to a sieving action by air depression with an Alpine air-jet sieve. Aerodynamic evaluation of fine particle dose and emitted dose was obtained using a Twin Stage Impinger (TSI). Drug concentration of powder blends used in dry powder inhalers influenced adhesion, content uniformity and in vitro deposition of the drug. For the higher concentration of formoterol, it seemed that a lower quantity of drug adhered to the lactose. This was confirmed by the aerosolization assays done in the TSI. The fine particle fraction increased linearly with the formoterol concentration. A correlation was observed between adhesion characteristics and inertial impaction. In the case of fluticasone, the influence of the concentration was different. First, the fine particle fraction increased with the concentration and then decreased with a further increase of the fluticasone concentration. This could be explained by the lack of homogeneity when the fluticasone concentration was high because of agglomerates of pure drug which can not be redispersed, or by the physico-chemical characteristics of this drug.

Air permeability of powder: a potential tool for Dry Powder Inhaler formulation development.

Dry Powder Inhalers have drawn great attention from pharmaceutical scientists in recent years in particular those consisting of low-dose micronized drug particles associated with larger carrier particles and called interactive mixtures. However, there is little understanding of the relation between bulk powder properties such as powder structure and its aerodynamic dispersion performance. The aim of this work was to develop a simple method to measure the air permeability of interactive mixtures used in Dry Powder Inhalers by using Blaine's apparatus--a compendial permeameter and to relate it to the aerodynamic behaviour. The study was done with fluticasone propionate and terbutaline sulphate as drug models that were blended with several lactoses having different particle size distribution thus containing different percentages of fine particle lactose. The quality of the blends was examined by analysing the drug content uniformity. Aerodynamic evaluation of fine particle fraction was obtained using a Twin Stage Impinger. A linear correlation between a bulk property--air permeability of packed powder bed--and the fine particle fraction of drug was observed for the tested drugs. The air permeability reflects the quantity of the free particle fraction in the interparticulate spaces of powder bed that leads to fine particle fraction during fluidization in air flow. A theoretical approach was developed in order to link the air permeability of powder bed and drag force acting on powders during aerosolization process. The permeability technique developed in this study provides a potential tool for screening Dry Powder Inhaler formulations at the development stage.

Arene-perfluoroarene interactions in crystal engineering. 4. Hexafluorobenzene-trans-stilbene (1/1).

In the title complex, C(6)F(6) x C(14)H(12), nearly parallel molecules of trans-stilbene and librationally disordered hexafluorobenzene form a mixed stack, with each molecule lying on an independent inversion centre. Adjacent stacks pack together in a herring-bone manner.

Nursing education, competency, and role in intravenous conscious sedation.

The advent of new hospital policies addressing analgesia and sedation motivates the nursing education department to implement an education plan for training RNs in the safe administration of medications that produce analgesia and sedation according to hospital policies. Learning materials must be procured or written, classroom content delineated, and a plan to precept all RNs who may be involved in IVCS procedures arranged. Our institution faced many obstacles in implementing such a program, including scheduling class time and clinical teaching time for IVCS preceptors, availability of IVCS procedures when preceptors and learners are available, and determining the course of action before a procedure requiring IVCS if the physician had not yet completed physician IVCS training. Obtaining quality monitoring data from these procedures is best initiated when the initial program is introduced. The RN's role in collecting quality monitoring data is crucial. The development of forms that include all required aspects of patient assessment, care, and monitoring promotes compliance with hospital policy.

Developing a competency-based program for conscious sedation.

This article reviews the growth of IVCS usage from OR to bedside, including criteria set by professional organizations and regulatory agencies, and presents the development of a competency-based program for the IVCS monitor. The planning and implementation process for the IVCS competency program is discussed in terms of phases selection of IVCS monitoring staff, training of staff, competency verification, and competency maintenance. Because health care institutions must address the professional and regulatory standards of practice in IVCS, quality management activities are essential.

Characteristics of gonadotropin response, follicular development, and endometrial growth and maturation across consecutive cycles of clomiphene citrate treatment.

OBJECTIVE: To examine the patterns of gonadotropin response, follicular development, and endometrial growth and maturation across consecutive cycles of clomiphene citrate (CC) treatment. DESIGN: Prospective analysis of cycle characteristics. SETTING: Academic tertiary medical center. PATIENTS: Nineteen consenting anovulatory infertile women receiving standardized, cyclic, incremental treatment with CC (50 to 150 mg/d, cycle days 5 to 9) for ovulation induction. INTERVENTIONS: In each of up to six consecutive treatment cycles, urinary LH was monitored twice daily from cycle day 10 until detection of the LH surge or day 21; blood samples and transvaginal ultrasound (US) examination were obtained on cycle days 3, 10, and every 1 to 3 days thereafter until collapse of the dominant follicle. Endometrial biopsy was performed 11 to 13 days after the LH surge in the first, third, and sixth ovulatory cycle. RESULTS: Follicular phase duration, peak follicular diameter, the number of preovulatory follicles, and peak endometrial thickness and echo pattern remained consistent across consecutive ovulatory (n = 55) and anovulatory (n = 23) treatment cycles. Endometrial dating was > or = 3 days out of phase in 2 of 31 (6%) cycles sampled. Peak serum E2 and P concentrations did not vary with cycle number or correlate with endometrial thickness or echo pattern. Cycle day 10 FSH levels were significantly higher in ovulatory subjects than in anovulatory subjects. CONCLUSIONS: Patterns of gonadotropin response, follicular development, and endometrial growth and maturation remain consistent across consecutive cycles of CC treatment.

Management of intermittent ovarian torsion by laparoscopic oophoropexy.

BACKGROUND: Ovarian torsion is a serious gynecologic condition that often results in adnexal removal. If recurrent, this can result in castration of young patients. Torsion in the pediatric population is rare, but it presents more management challenges for gynecologists. There are few reports of prophylactic oophoropexy in patients with intermittent torsion. CASE: A patient with a history of left adnexal torsion was treated with salpingo-oophorectomy at age 10. She subsequently presented at age 12 with right lower quadrant pain, and was found to have a 7 x 6 cm right adnexal mass on ultrasound examination. She was diagnosed with ovarian edema secondary to intermittent torsion. At laparoscopy, she was found to have a 3-cm utero-ovarian ligament. She was treated with laparoscopic shortening of the utero-ovarian ligament, and has remained symptom-free for 1 year. CONCLUSION: We believe that this is the first reported case of laparoscopic triplication of the utero-ovarian ligament to prevent recurrent torsion. In young patients, this treatment may be a reasonable alternative to oophoropexy as prophylaxis for ovarian torsion.

Single vs. multiple semen specimens in screening for male infertility factors. A comparison.

OBJECTIVE: To reevaluate the number of semen analyses necessary to establish whether further male infertility testing is necessary. STUDY DESIGN: The results of three consecutive semen analyses for infertility evaluations were retrospectively reviewed. A male factor was defined by an abnormal semen analysis if either the first specimen of three (single-sample screening) or two of the three specimens (multiple-sample screening) met World Health Organization criteria. Males considered abnormal by multiple-sample screening underwent sophisticated andrologic evaluation. RESULTS: A single-sample conventional semen analysis obtained from 209 males demonstrated a diagnostic accuracy of 10.4% false negatives and a sensitivity of 89.6% when compared to that of multiple-sample analysis. Andrologic evaluation of abnormal males by multiple-sample screening confirmed that 9 of the 11 men with normal first specimens were abnormal; all others were confirmed as abnormal. CONCLUSION: Analysis of multiple semen specimens provides a reliable screen in the evaluation of male factor infertility when the goal is to minimize the false negative rate of screening tests.

A strategy for responding to the training needs of nursing staff in a new cardiac/neurosurgical ICU and telemetry unit.

The decision of the Brigham and Women's Hospital (BWH) to expand its capacity to care for acute cardiac surgical and neurosurgical patients resulted in the need for an education and training program for a large group of nursing staff. In such situations, where an existing service is being expanded or a new service initiated, nursing education departments must quickly devise simple and cost-effective mechanisms to promote the competency of nursing staff. Nurse educators, staff nurses, nurse managers, and clinical nurse specialists all play a role in planning and implementing the relevant education and evaluation program. BWH chose to recruit temporary special projects staff nurses to address these increased educational needs.

Aberrant hypothalamic-pituitary-ovarian axis in the Watanabe heritable hyperlipidemic rabbit.

The WHHL rabbit has a defective low density lipoprotein receptor and is a model for familial hypercholesterolemia. WHHL rabbits are less fecund than NZW rabbits, the strain into which the defect has been inbred. This lower fecundity could be related to impaired ovarian steroidogenesis due to reduced intracellular availability of cholesterol. Here we compare the WHHL and NZW rabbits with regard to oocyte morphology and fertilization rates after stimulation with equine chorionic gonadotropin. We also compare hypothalamic-pituitary-ovarian axis function by measuring baseline and gonadotropin releasing hormone-stimulated plasma estradiol, progesterone, and gonadotropin levels, both before and after simvastatin inhibition of de novo cholesterol synthesis. WHHL rabbit oocytes remained encased in cumulus and had a lowered fertilization rate (9/50 vs. 83/87, P < 0.05). WHHL rabbits had lower baseline estradiol levels (7.1 +/- 0.72 vs. 10.2 +/- 0.94, P < 0.05) and had higher baseline follicle stimulating hormone (P < 0.05) and luteinizing hormone (P < 0.05) levels. Simvastatin lowered luteal progesterone concentrations only in WHHL rabbits (P < 0.05). We conclude that the hypothalamic-pituitary-ovarian axis in WHHL rabbits is abnormal. The reduced availability of intracellular cholesterol for progesterone synthesis by inhibition of de novo cholesterol biosynthesis leads to a significant reduction in plasma progesterone concentrations in the WHHL. These findings have implications for women with familial hypercholesterolemia, particularly regarding treatment with inhibitors of de novo cholesterol synthesis.

Expressive characteristics of anxiety in depressed men and women.

This study was aimed at identifying the expressive, movement, and social behaviors associated with anxiety in the syndrome of major depression. The sample consisted of 97 hospitalized male and female depressed patients. Expressive and social behaviors were evaluated prior to treatment in a structured videotaped interview. Anxiety was measured using a multi-vantaged approach including doctor's rating, nurse's rating, patient self-report, and a separate video rating. Results indicate that anxiety was significantly associated with agitation, distressed facial expression, bodily discomfort, and poor social interaction in both sexes. Men and women differed in certain respects: anxiety was highly related to motor retardation in women only, and to hostility in men only. Differences in the pattern of expressive behavior between high and low anxious, depressed patients were clearly significant, and several were large enough to serve as clinical indicators. These findings help to characterize the expressive features of anxiety in the context of severe depression, and add to the growing literature on sex differences in depression.