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ACS Nano ; 13(10): 11062-11069, 2019 10 22.
Article in English | MEDLINE | ID: mdl-31490647

ABSTRACT

We present a method for the computational image analysis of high frequency guided sound waves based upon the measurement of optical interference fringes, produced at the air interface of a thin film of liquid. These acoustic actuations induce an affine deformation of the liquid, creating a lensing effect that can be readily observed using a simple imaging system. We exploit this effect to measure and analyze the spatiotemporal behavior of the thin liquid film as the acoustic wave interacts with it. We also show that, by investigating the dynamics of the relaxation processes of these deformations when actuation ceases, we are able to determine the liquid's viscosity using just a lens-free imaging system and a simple disposable biochip. Contrary to all other acoustic-based techniques in rheology, our measurements do not require monitoring of the wave parameters to obtain quantitative values for fluid viscosities, for sample volumes as low as 200 pL. We envisage that the proposed methods could enable high throughput, chip-based, reagent-free rheological studies within very small samples.

3.
PLoS One ; 14(2): e0210497, 2019.
Article in English | MEDLINE | ID: mdl-30807573

ABSTRACT

BACKGROUND: In economic analyses of HIV interventions, South Africa is often used as a case in point, due to the availability of good epidemiological and programme data and the global relevance of its epidemic. Few analyses however use locally relevant cost data. We reviewed available cost data as part of the South African HIV Investment Case, a modelling exercise to inform the optimal use of financial resources for the country's HIV programme. METHODS: We systematically reviewed publication databases for published cost data covering a large range of HIV interventions and summarised relevant unit costs (cost per person receiving a service) for each. Where no data was found in the literature, we constructed unit costs either based on available information regarding ingredients and relevant public-sector prices, or based on expenditure records. RESULTS: Only 42 (5%) of 1,047 records included in our full-text review reported primary cost data on HIV interventions in South Africa, with 71% of included papers covering ART. Other papers detailed the costs of HCT, MMC, palliative and inpatient care; no papers were found on the costs of PrEP, social and behaviour change communication, and PMTCT. The results informed unit costs for 5 of 11 intervention categories included in the Investment Case, with the remainder costed based on ingredients (35%) and expenditure data (10%). CONCLUSIONS: A large number of modelled economic analyses of HIV interventions in South Africa use as inputs the same, often outdated, cost analyses, without reference to additional literature review. More primary cost analyses of non-ART interventions are needed.


Subject(s)
HIV Infections/economics , Anti-HIV Agents/economics , Antiretroviral Therapy, Highly Active/economics , Costs and Cost Analysis , HIV Infections/epidemiology , HIV Infections/therapy , Humans , Models, Economic , Patient Care/economics , Patient Education as Topic/economics , South Africa/epidemiology
4.
Appl Plant Sci ; 6(2): e1023, 2018 Feb.
Article in English | MEDLINE | ID: mdl-29732254

ABSTRACT

PREMISE OF THE STUDY: Biological collections are uniquely poised to inform the stewardship of life on Earth in a time of cataclysmic biodiversity loss. Efforts to fully leverage collections are impeded by a lack of trained taxonomists and a lack of interest and engagement by the public. We provide a model of a crowd-sourced data collection project that produces quality taxonomic data sets and empowers citizen scientists through real contributions to science. Entitled MicroPlants, the project is a collaboration between taxonomists, citizen science experts, and teachers and students from universities and K-12. METHODS: We developed an online tool that allows citizen scientists to measure photographs of specimens of a hyper-diverse group of liverworts from a biodiversity hotspot. RESULTS: Using the MicroPlants online tool, citizen scientists are generating high-quality data, with preliminary analysis indicating non-expert data can be comparable to expert data. DISCUSSION: More than 11,000 users from both the website and kiosk versions have contributed to the data set, which is demonstrably aiding taxonomists working toward establishing conservation priorities within this group. MicroPlants provides opportunities for public participation in authentic science research. The project's educational component helps move youth toward engaging in scientific thinking and has been adopted by several universities into curriculum for both biology and non-biology majors.

5.
Aesthet Surg J ; 33(5): 698-704, 2013 Jul.
Article in English | MEDLINE | ID: mdl-23718978

ABSTRACT

BACKGROUND: Although clinical evidence of successful autologous fat transfer (AFT) using third-generation ultrasound-assisted liposuction (UAL) is readily available, no study has quantified adipocyte viability using standardized methods. OBJECTIVES: The authors assess acute adipocyte viability following fat aspiration as a first step in determining the overall efficacy of using third-generation UAL for AFT. METHODS: Lipoaspirate samples were collected from patients who underwent elective liposuction procedures at multiple surgery centers. Patients with a history of bleeding disorders, diabetes, human immunodeficiency virus, or lipoatrophy disorders were excluded. The UAL system (VASER; Sound Surgical Technologies, Inc, Louisville, Colorado) was set at 60% amplitude in pulsed mode with vacuum aspiration of 15 in Hg or less. Laboratory analysis included free lipid volume, viability via lipolysis and propidium iodide staining, and cytological analysis, including cell surface protein examination and hematoxylin and eosin staining. RESULTS: The lipolysis assay revealed metabolically active adipocytes with a mean (SD) correlative viability of 85.1% (11%). Direct measures of acute viability via propidium iodide staining resulted in a mean (SD) viability measure of 88.7% (3.5%). Both mean values are within the historical range reported from syringe and vacuum-assisted lipoaspiration. Aqueous and lipid contents were favorably reduced after washing and filtering (Puregraft system; Cytori Therapeutics, Inc, San Diego, California). Cellular phenotypes identified were primarily white blood cells or vascular endothelial and vascular associated cells. CONCLUSIONS: Adipose tissue acquired via third-generation UAL is viable at harvest and is potentially a suitable source for autologous fat grafts. These results confirm reported clinical successes utilizing third-generation ultrasound lipoaspirate for AFT.


Subject(s)
Adipocytes/physiology , Adipose Tissue/transplantation , Lipectomy/methods , Ultrasonic Therapy/methods , Adipocytes/transplantation , Adipose Tissue/diagnostic imaging , Adipose Tissue/pathology , Adult , Biopsy, Needle , Cell Survival/physiology , Female , Humans , Immunohistochemistry , Male , Middle Aged , Sampling Studies , Tissue and Organ Harvesting/methods , Transplantation, Autologous , Treatment Outcome , Ultrasonography , Young Adult
7.
Science ; 334(6061): 1372-7, 2011 Dec 09.
Article in English | MEDLINE | ID: mdl-22096101

ABSTRACT

Most malaria drug development focuses on parasite stages detected in red blood cells, even though, to achieve eradication, next-generation drugs active against both erythrocytic and exo-erythrocytic forms would be preferable. We applied a multifactorial approach to a set of >4000 commercially available compounds with previously demonstrated blood-stage activity (median inhibitory concentration < 1 micromolar) and identified chemical scaffolds with potent activity against both forms. From this screen, we identified an imidazolopiperazine scaffold series that was highly enriched among compounds active against Plasmodium liver stages. The orally bioavailable lead imidazolopiperazine confers complete causal prophylactic protection (15 milligrams/kilogram) in rodent models of malaria and shows potent in vivo blood-stage therapeutic activity. The open-source chemical tools resulting from our effort provide starting points for future drug discovery programs, as well as opportunities for researchers to investigate the biology of exo-erythrocytic forms.


Subject(s)
Antimalarials/pharmacology , Drug Discovery , Imidazoles/pharmacology , Liver/parasitology , Malaria/drug therapy , Piperazines/pharmacology , Plasmodium/drug effects , Animals , Antimalarials/chemistry , Antimalarials/pharmacokinetics , Antimalarials/therapeutic use , Cell Line, Tumor , Drug Evaluation, Preclinical , Drug Resistance , Erythrocytes/parasitology , Humans , Imidazoles/chemistry , Imidazoles/pharmacokinetics , Imidazoles/therapeutic use , Malaria/parasitology , Malaria/prevention & control , Mice , Mice, Inbred BALB C , Molecular Structure , Piperazines/chemistry , Piperazines/pharmacokinetics , Piperazines/therapeutic use , Plasmodium/cytology , Plasmodium/growth & development , Plasmodium/physiology , Plasmodium berghei/cytology , Plasmodium berghei/drug effects , Plasmodium berghei/growth & development , Plasmodium berghei/physiology , Plasmodium falciparum/cytology , Plasmodium falciparum/drug effects , Plasmodium falciparum/growth & development , Plasmodium falciparum/physiology , Plasmodium yoelii/cytology , Plasmodium yoelii/drug effects , Plasmodium yoelii/growth & development , Plasmodium yoelii/physiology , Polymorphism, Single Nucleotide , Protozoan Proteins/chemistry , Protozoan Proteins/genetics , Protozoan Proteins/metabolism , Random Allocation , Small Molecule Libraries , Sporozoites/drug effects , Sporozoites/growth & development
8.
Craniomaxillofac Trauma Reconstr ; 2(3): 151-60, 2009 Oct.
Article in English | MEDLINE | ID: mdl-22110809

ABSTRACT

Bone substitutes are being increasingly used in craniofacial surgery and craniomaxillofacial trauma. We will review the history of the biomaterials and describe the ideal characteristics of bone substitutes, with a specific emphasis on craniofacial reconstruction. Some of the most commonly used bone substitutes are discussed in more depth, such as calcium phosphate and hydroxyapatite ceramics and cements, bioactive glass, and polymer products. Areas of active research and future directions include tissue engineering, with an increasing emphasis on bioactivity of the implant.

9.
Obes Surg ; 18(6): 644-7, 2008 Jun.
Article in English | MEDLINE | ID: mdl-18368462

ABSTRACT

BACKGROUND: It is well known that obesity is accompanied by changes in thyroid function. Hypothyroidism is associated with increased body weight. The aim of this study was to evaluate the operative outcomes, weight loss, and the effect of weight loss on thyroid function in morbidly obese patients with hypothyroidism who undergo laparoscopic Roux-en-Y gastric bypass (LRYGB) surgery. METHODS: A retrospective review of 20 morbidly obese female patients with hypothyroidism and on thyroid replacement therapy who underwent LRYGB between January 2003 and August 2006. RESULTS: Mean preoperative body mass index (BMI) was 47.6 kg/m2 (range 38-58.5 kg/m2). Average patient age was 44.5 years (range 21-66 years). There was one early complication (pneumonia). Late complications included one death, three anastomotic strictures, and one small bowel obstruction. The patients were followed for a mean of 13.5 months (range 3-24 months). Their mean excess body weight loss was 13 kg (22%), 24.4 kg (39.4%), 33.2 kg (63.3%), 38.4 kg (65%), 41.7 kg (70%), and 43 kg (73%) at 1, 3, 6, 9, 12, and 24 months, respectively. Change in a mean BMI was the same regardless of the patient preoperative and postoperative thyroxine dose. Hypothyroidism resolved in 5(25%) patients, improved in 2(10%) patients, unchanged in 8(40%) patients, and worsened in 5 (25%) patients. Most of the five whose hypothyroidism worsened had thyroid autoimmune disease. CONCLUSIONS: Hypothyroidism appears to improve in the vast majority of morbidly obese patients who undergo LRYGB, except for those whose thyroid disease is autoimmune in nature.


Subject(s)
Gastric Bypass , Hypothyroidism/complications , Laparoscopy , Obesity, Morbid/surgery , Adult , Aged , Humans , Hypothyroidism/blood , Hypothyroidism/drug therapy , Middle Aged , Obesity, Morbid/complications , Thyroxine/blood , Thyroxine/therapeutic use
10.
Int J Radiat Oncol Biol Phys ; 67(5): 1389-93, 2007 Apr 01.
Article in English | MEDLINE | ID: mdl-17394942

ABSTRACT

PURPOSE: To determine the safety and efficacy of preoperative hypofractionated radiotherapy using intensity-modulated radiotherapy (IMRT) and an incorporated boost with concurrent capecitabine in patients with locally advanced rectal cancer. METHODS AND MATERIALS: The eligibility criteria included adenocarcinoma of the rectum, T3-T4 and/or N1-N2 disease, performance status 0 or 1, and age > or =18 years. Photon IMRT and an incorporated boost were used to treat the whole pelvis to 45 Gy and the gross tumor volume plus 2 cm to 55 Gy in 25 treatments within 5 weeks. The study was designed to escalate the dose to the gross tumor volume in 5-Gy increments in 3-patient cohorts. Capecitabine was given orally 825 mg/m(2) twice daily for 7 days each week during RT. The primary endpoint was the maximal tolerated radiation dose, and the secondary endpoints were the pathologic response and quality of life. RESULTS: Eight patients completed RT at the initial dose level of 55 Gy. The study was discontinued because of toxicity-six Grade 3 toxicities occurred in 3 (38%) of 8 patients. All patients went on to definitive surgical resection, and no patient had a pathologically complete response. CONCLUSION: This regimen, using hypofractionated RT with an incorporated boost, had unacceptable toxicity despite using standard doses of capecitabine and IMRT. Additional research is needed to determine whether IMRT is able to reduce the side effects during and after pelvic RT with conventional dose fractionation.


Subject(s)
Antimetabolites, Antineoplastic/therapeutic use , Deoxycytidine/analogs & derivatives , Fluorouracil/analogs & derivatives , Radiotherapy, Intensity-Modulated/adverse effects , Rectal Neoplasms/drug therapy , Rectal Neoplasms/radiotherapy , Aged , Antimetabolites, Antineoplastic/adverse effects , Capecitabine , Combined Modality Therapy/methods , Deoxycytidine/adverse effects , Deoxycytidine/therapeutic use , Dose Fractionation, Radiation , Female , Fluorouracil/adverse effects , Fluorouracil/therapeutic use , Humans , Intraoperative Period , Male , Maximum Tolerated Dose , Middle Aged , Photons/therapeutic use , Quality of Life , Radiotherapy, Intensity-Modulated/methods , Rectal Neoplasms/pathology
11.
J Womens Health (Larchmt) ; 16(1): 134-8, 2007.
Article in English | MEDLINE | ID: mdl-17324104

ABSTRACT

OBJECTIVES: To assess the current perspective of regional obstetrician/gynecologists on providing primary/preventive healthcare, including their desire to provide primary care in their practices and whether or not they are adequately trained as primary care providers. METHODS: A self-administered survey with a Likert scale that included demographic information and questions about the practice of primary healthcare was mailed to regional obstetrician/gynecologists both in practice and in residency training. RESULTS: One hundred thirty-nine physicians responded to the survey (33% response rate). Respondents were divided (48% agreed vs. 52% disagreed) when asked if obstetrician/gynecologists should be considered primary healthcare providers. When asked if they viewed themselves as specialists who also provide primary care for women, the majority of physicians (62%) agreed. The majority of physicians (64%) disagreed when asked if they wanted to include primary care in their practice. When asked if they thought that they were adequately trained to provide primary healthcare, respondents were divided (47% agreed vs. 53% disagreed). However, a significant gender difference was found between respondents, with male physicians being more likely than female physicians to agree (55% vs. 33%, p < 0.05) when asked if they were adequately trained to provide primary care. CONCLUSIONS: In this regional study of obstetrician/gynecologists, physician opinions were divided regarding their status as primary care providers, but the majority of respondents did not want to include primary healthcare in their practice. A significant gender difference exists between physicians with regard to the question of adequate training for primary care, with male obstetrician/gynecologists being more likely as to agree that they are adequately trained to provide primary care.


Subject(s)
Attitude of Health Personnel , Gynecology/statistics & numerical data , Obstetrics/statistics & numerical data , Practice Patterns, Physicians'/statistics & numerical data , Preventive Health Services/statistics & numerical data , Primary Health Care/statistics & numerical data , Adult , Female , Health Care Surveys , Humans , Male , Mid-Atlantic Region , Middle Aged , Women's Health Services/statistics & numerical data
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