Connected Droplet Shape Analysis for Nanoflow Quantification in Thin Electroosmotic Micropumps and a Tunable Convex Lens Application.

Thin electroosmotic flow (EOF) micropumps can generate flow in confined spaces such as lab-on-a-chip microsystems and implantable drug delivery devices. However, status quo methods for quantifying flow and other important parameters in EOF micropumps depend on microfluidic interconnects or fluorescent particle tracking: methods that can be complex and error-prone. Here, we present a novel connected droplet shape analysis (CDSA) technique that simplifies flow rate and zeta potential quantification in thin EOF micropumps. We also show that a pair of droplets connected by an EOF pump can function as a tunable convex lens system (TCLS). We developed a biocompatible and all polymer EOF micropump with an SU-8 substrate and poly(3,4-ethylenedioxythiophene) polystyrene sulfonate (PEDOT:PSS) electrodes. We microdrilled a channel through the electrode/SU-8/electrode layers to realize a monolithic EOF micropump. Then, we deposited a pinned droplet on each end of the microchannel so that it connected them. By controlling the EOF between the droplets and measuring the corresponding change in their shape, we quantified the nanoliter EOF rate and zeta potential at the interface of SU-8 with two liquids (deionized water and a l-glutamate neurotransmitter solution). When the droplet pair and pump were used as a TCLS, CDSA successfully predicted how the focal length would change when the pump drove fluid from one droplet to another. In summary, CDSA is a simple low-cost technique for EOF rate and zeta potential measurement, and a pair of droplets connected by an EOF micropump can function as a TCLS without any moving parts.

Effect of repeated compaction of tablets on tablet properties and work of compaction using an instrumented laboratory tablet press.

The repeated compaction of Avicel PH101, dicalcium phosphate dihydrate (DCP) powder, 50:50 DCP/Avicel PH101 and Starch 1500 was studied using an instrumented laboratory tablet press which measures upper punch force, punch displacement and ejection force and operates using a V-shaped compression profile. The measurement of work compaction was demonstrated, and the test materials were ranked in order of compaction behaviour Avicel PH101 > DCP/Avicel PH101 > Starch > DCP. The behaviour of the DCP/Avicel PH101 mixture was distinctly non-linear compared with the pure components. Repeated compaction and precompression had no effect on the tensile fracture strength of Avicel PH101 tablets, although small effects on friability and disintegration time were seen. Repeated compaction and precompression reduced the tensile strength and the increased disintegration time of the DCP tablets, but improved the strength and friability of Starch 1500 tablets. Based on the data reported, routine laboratory measurement of tablet work of compaction may have potential as a critical quality attribute of a powder blend for compression. The instrumented press was suitable for student use with minimal supervisor input.

Identification of new adventitious rooting mutants amongst suppressors of the Arabidopsis thaliana superroot2 mutation.

The plant hormone auxin plays a central role in adventitious rooting and is routinely used with many economically important, vegetatively propagated plant species to promote adventitious root initiation and development on cuttings. Nevertheless the molecular mechanisms through which it acts are only starting to emerge. The Arabidopsis superroot2-1 (sur2-1) mutant overproduces auxin and, as a consequence, develops excessive adventitious roots in the hypocotyl. In order to increase the knowledge of adventitious rooting and of auxin signalling pathways and crosstalk, this study performed a screen for suppressors of superroot2-1 phenotype. These suppressors provide a new resource for discovery of genetic players involved in auxin signalling pathways or at the crosstalk of auxin and other hormones or environmental signals. This study reports the identification and characterization of 26 sur2-1 suppressor mutants, several of which were identified as mutations in candidate genes involved in either auxin biosynthesis or signalling. In addition to confirming the role of auxin as a central regulator of adventitious rooting, superroot2 suppressors indicated possible crosstalk with ethylene signalling in this process.

Factors associated with non-participation in one or two follow-up phases in a cohort study of injured adults.

OBJECTIVE: To identify factors associated with non-participation at the 12-month and 24-month follow-up phases of a prospective cohort study of injury outcomes. METHODS: Associations between non-participation at follow-up phases and a range of sociodemographic, injury, health, outcome and administrative factors were examined. RESULTS: An individual's non-participation at 12 months did not necessarily mean non-participation at 24 months. Sociodemographic factors were the most salient for non-participation, regardless of the number of follow-up phases or specific phase considered. CONCLUSIONS: Retention rates in prospective cohort studies of injury outcome may be improved by follow-up of everyone irrespective of previous non-participation, focusing resources to retain men, young adults, indigenous people and those living with people other than family members, and by ensuring that multiple alternative participant contacts are obtained. There is sufficient evidence to be concerned about potential bias given that several of the factors we, and others, have identified as associated with non-participation are also associated with various functional and disability outcomes following injury. This suggests detailed investigations are warranted into the effect non-participation may be having on the estimates for various outcomes.

Costs of injury in New Zealand: Accident Compensation Corporation spending, personal spending and quality-adjusted life years lost.

BACKGROUND: New Zealand offers a unique opportunity for cost-of-injury research due to its comprehensive, no-fault injury compensation insurance scheme, which is managed by the government-controlled Accident Compensation Corporation (ACC). OBJECTIVES: To estimate the costs of injury in New Zealand with respect to ACC's spending for entitlement claimants (ie, people with injuries requiring more than 'treatment only'), as well as injured individuals' out-of-pocket personal spending and non-pecuniary costs in terms of effects on health-related quality of life (HRQoL). METHODS: A prospective cohort study of people injured between June 2007 and May 2009 was followed for 12 months after injury. ACC's spending for each participant (n=2215) was estimated from ACC data. Out-of-pocket personal spending and quality-adjusted life years (QALYs) lost were estimated based on interviews conducted at 3, 5 and 12 months post injury. RESULTS: For the cohort studied, most of the reported financial costs of injury were met by ACC. ACC spending was higher for individuals with more severe injuries and ones admitted to hospital. There was no difference in mean personal spending between people who were hospitalised or not, or between those with minor or moderate injuries, although individuals with more severe injuries reported higher personal spending. CONCLUSIONS: Overall, the ACC appears to be performing well supporting injured people financially. Nonetheless, people with more severe injuries incur substantial out-of-pocket expenses. Costs are higher for hospitalised and more severe injuries, but non-hospitalised and less severe cases can still incur substantial costs. The HRQoL effects of injury-naturally, borne by injured individuals themselves-are relatively large on average.

A collection of INDEL markers for map-based cloning in seven Arabidopsis accessions.

The availability of a comprehensive set of resources including an entire annotated reference genome, sequenced alternative accessions, and a multitude of marker systems makes Arabidopsis thaliana an ideal platform for genetic mapping. PCR markers based on INsertions/DELetions (INDELs) are currently the most frequently used polymorphisms. For the most commonly used mapping combination, Columbia×Landsberg erecta (Col-0×Ler-0), the Cereon polymorphism database is a valuable resource for the generation of polymorphic markers. However, because the number of markers available in public databases for accessions other than Col-0 and Ler-0 is extremely low, mapping using other accessions is far from straightforward. This issue arose while cloning mutations in the Wassilewskija (Ws-4) background. In this work, approaches are described for marker generation in Ws-4 x Col-0. Complementary strategies were employed to generate 229 INDEL markers. Firstly, existing Col-0/Ler-0 Cereon predicted polymorphisms were mined for transferability to Ws-4. Secondly, Ws-0 ecotype Illumina sequence data were analyzed to identify INDELs that could be used for the development of PCR-based markers for Col-0 and Ws-4. Finally, shotgun sequencing allowed the identification of INDELs directly between Col-0 and Ws-4. The polymorphism of the 229 markers was assessed in seven widely used Arabidopsis accessions, and PCR markers that allow a clear distinction between the diverged Ws-0 and Ws-4 accessions are detailed. The utility of the markers was demonstrated by mapping more than 35 mutations in a Col-0×Ws-4 combination, an example of which is presented here. The potential contribution of next generation sequencing technologies to more traditional map-based cloning is discussed.

Endoscopic management of posttraumatic supraglottic stenosis in the pediatric population.

OBJECTIVES: Pediatric blunt laryngeal trauma is a rare and potentially life-threatening entity. External injuries can be misleading, and a high index of suspicion, as well as early intervention, is essential to achieve the best possible outcome. The authors of this report review the management of blunt laryngeal trauma in the pediatric population and describe the endoscopic management of posttraumatic supraglottic stenosis. METHODS: Methods used were case report from a tertiary referral institution and review of the literature. RESULTS: We describe the case of a 13-year-old girl whom developed supraglottic stenosis following blunt laryngeal trauma. Innovative endoscopic techniques were used in the successful management of this exceedingly rare entity. CONCLUSION: Early recognition and intervention are of paramount importance if successful endoscopic management of blunt laryngeal trauma is to be considered.

Assessment of the impedance cardiogram recorded by an automated external defibrillator during clinical cardiac arrest.

OBJECTIVE: To assess the impedance cardiogram recorded by an automated external defibrillator during cardiac arrest to facilitate emergency care by lay persons. Lay persons are poor at emergency pulse checks (sensitivity 84%, specificity 36%); guidelines recommend they should not be performed. The impedance cardiogram (dZ/dt) is used to indicate stroke volume. Can an impedance cardiogram algorithm in a defibrillator determine rapidly circulatory arrest and facilitate prompt initiation of external cardiac massage? DESIGN: Clinical study. SETTING: University hospital. PATIENTS: Phase 1 patients attended for myocardial perfusion imaging. Phase 2 patients were recruited during cardiac arrest. This group included nonarrest controls. INTERVENTIONS: The impedance cardiogram was recorded through defibrillator/electrocardiographic pads oriented in the standard cardiac arrest position. MEASUREMENTS AND MAIN RESULTS: Phase 1: Stroke volumes from gated myocardial perfusion imaging scans were correlated with parameters from the impedance cardiogram system (dZ/dt(max) and the peak amplitude of the Fast Fourier Transform of dZ/dt between 1.5 Hz and 4.5 Hz). Multivariate analysis was performed to fit stroke volumes from gated myocardial perfusion imaging scans with linear and quadratic terms for dZ/dt(max) and the Fast Fourier Transform to identify significant parameters for incorporation into a cardiac arrest diagnostic algorithm. The square of the peak amplitude of the Fast Fourier Transform of dZ/dt was the best predictor of reduction in stroke volumes from gated myocardial perfusion imaging scans (range = 33-85 mL; p = .016). Having established that the two pad impedance cardiogram system could detect differences in stroke volumes from gated myocardial perfusion imaging scans, we assessed its performance in diagnosing cardiac arrest. Phase 2: The impedance cardiogram was recorded in 132 "cardiac arrest" patients (53 training, 79 validation) and 97 controls (47 training, 50 validation): the diagnostic algorithm indicated cardiac arrest with sensitivities and specificities (+/- exact 95% confidence intervals) of 89.1% (85.4-92.1) and 99.6% (99.4-99.7; training) and 81.1% (77.6-84.3) and 97% (96.7-97.4; validation). CONCLUSIONS: The impedance cardiogram algorithm is a significant marker of circulatory collapse. Automated defibrillators with an integrated impedance cardiogram could improve emergency care by lay persons, enabling rapid and appropriate initiation of external cardiac massage.

The impedance cardiogram recorded through two electrocardiogram/defibrillator pads as a determinant of cardiac arrest during experimental studies.

OBJECTIVE: Laypersons are poor at emergency pulse checks (sensitivity 84%, specificity 36%). Guidelines indicate that pulse checks should not be performed. The impedance cardiogram (dZ/dt) is used to assess stroke volume. Can a novel defibrillator-based impedance cardiogram system be used to distinguish between circulatory arrest and other collapse states? DESIGN: Animal study. SETTING: University research laboratory. SUBJECTS: Twenty anesthetized, mechanically ventilated pigs, weight 50-55 kg. INTERVENTIONS: Stroke volume was altered by right ventricular pacing (160, 210, 260, and 305 beats/min). Cardiac arrest states were then induced: ventricular fibrillation (by rapid ventricular pacing) and, after successful defibrillation, pulseless electrical activity and asystole (by high-dose intravenous pentobarbitone). MEASUREMENTS AND MAIN RESULTS: The impedance cardiogram was recorded through electrocardiogram/defibrillator pads in standard cardiac arrest positions. Simultaneously recorded electro- and impedance cardiogram (dZ/dt) along with arterial blood pressure tracings were digitized during each pacing and cardiac arrest protocol. Five-second epochs were analyzed for sinus rhythm (20 before ventricular fibrillation, 20 after successful defibrillation), ventricular fibrillation (40), pulseless electrical activity (20), and asystole (20), in two sets of ten pigs (ten training, ten validation). Standard impedance cardiogram variables were noncontributory in cardiac arrest, so the fast Fourier transform of dZ/dt was assessed. During ventricular pacing, the peak amplitude of fast Fourier transform of dZ/dt (between 1.5 and 4.5 Hz) correlated with stroke volume (r2 = .3, p < .001). In cardiac arrest, a peak amplitude of fast Fourier transform of dZ/dt of < or = 4 dB x ohm x rms indicated no output with high sensitivity (94% training set, 86% validation set) and specificity (98% training set, 90% validation set). CONCLUSIONS: As a powerful clinical marker of circulatory collapse, the fast Fourier transformation of dZ/dt (impedance cardiogram) has the potential to improve emergency care by laypersons using automated defibrillators.

Identification of new splice variants and differential expression of the human kallikrein 10 gene, a candidate cancer biomarker.

The human kallikrein gene 10 (KLK10) is a member of the kallikrein gene family on chromosome 19q13.4. This gene was identified by its downregulation in breast cancer, and preliminary evidence suggests that it may act as a tumor suppressor. A computer-based analysis was performed on EST and SAGE clones from the Cancer Genome Anatomy Project and other databases. Experimental verification of differential expression of KLK10 in cancer was performed by PCR using gene-specific primers. The mRNA and EST analysis allowed the construction of the longest transcript of the gene and characterization of a 5' extension of the reported mRNA. In addition, seven new splice variants of KLK10 were identified. One of these variants, named KLK10 splice variant 3 (KLK10-SV3) which starts with a novel first exon, was experimentally verified. This variant is predicted to encode for the same protein as the 'classical' KLK10 mRNA, since the first exon is untranslated. One variant mRNA partially matches with the sequence of KLK10, while the rest of the mRNA matches with a portion of the polycystic kidney disease gene, found on chromosome 15. This variant could not be experimentally verified in either normal or cancerous tissues. There are 39 reported single nucleotide polymorphisms (SNPs) for the gene, in which three result in amino acid substitutions. SAGE analysis shows a clear upregulation of KLK10 in ovarian, pancreatic, colon, and gastric cancers. The gene is, however, downregulated in breast and prostate cancers. A three-fold decrease in expression levels was noted in actinic keratosis, compared to normal skin from the same patient. The differential regulation of KLK10 in ovarian and prostate cancers was experimentally verified by RT-PCR analysis. In addition, a significant number of clones were isolated from carcinomas of the head and neck. Fewer clones were found in carcinomas of the skin, brain and prostate. Orthologues were identified in three other species, with the highest degree of homology observed with the mouse and rat orthologues (42% in each). In conclusion new splice variants of the KLK10 gene were identified. These in silico analyses show a differential expression of the gene in various malignancies and provide the basis for directing experimental efforts to investigate the possible role of the gene as a cancer biomarker.

Differential expression of a human kallikrein 5 (KLK5) splice variant in ovarian and prostate cancer.

The presence of more than one mRNA form is common among kallikrein genes. We identified an mRNA transcript of the human kallikrein gene 5 (KLK5), denoted KLK5 splice variant 1 (KLK5-SV1). This variant has a different 5'-splice site, but encodes the same protein as the classical KLK5 transcript. RT-PCR analysis of this variant transcript expression in 29 human tissues indicated highest expression in the cervix, salivary gland, kidney, mammary gland, and skin. Comparative analysis of the expression levels of KLK5-SV1, another splice variant named KLK5 splice variant 2 (KLK5-SV2), and the classical KLK5 form showed that out of all three mRNA transcripts, the classical form is predominantly expressed (found in more tissues and at higher expression levels) followed by KLK5-SV1. KLK5-SV1 is expressed at high levels in ovarian, pancreatic, breast and prostate cancer cell lines. KLK5-SV1 was also found to be expressed in 9/10 ovarian cancer tissues, but it was not found in one normal ovarian tissue tested. Hormonal regulation experiments suggest that KLK5-SV1 is regulated by steroid hormones in the BT-474 breast cancer cell line. Furthermore, this variant had significantly higher expression in normal prostate tissues compared to their matched cancer tissue counterparts. KLK5-SV1 may have clinical utility in various malignancies and should be further explored as a potential new biomarker for prostate and ovarian cancer.

The kallikrein gene 5 splice variant 2 is a new biomarker for breast and ovarian cancer.

The presence of more than one mRNA form for the same gene is common among kallikreins, and many of the kallikrein splice variants may hold significant clinical value. The human kallikrein gene 5 (KLK5) is a member of the human kallikrein gene family of serine proteases on chromosome 19q13.4. KLK5 has been shown to be differentially expressed in a variety of endocrine tumors including ovarian, breast and prostate cancer. Utilizing Expressed Sequence Tag database analysis and reverse transcriptase polymerase chain reaction, we identified a new alternatively spliced form of KLK5(KLK5-splice variant 2, KLK5-SV2). This variant mRNA is 1,438 bp in length; formed of 195 bp of 5' untranslated region, 882 bp of protein coding sequence and a 3' untranslated region of 326 nucleotides. KLK5-SV2 has 7 exons, the first 2 of which are untranslated, and 6 intervening introns. KLK5-SV2 is different from the classic form of the KLK5 mRNA in its 5' untranslated region, where the first 5' untranslated exon of the classic form is split into 2 exons with an intervening intron of 135 nucleotides. KLK5-SV2 is expressed in a variety of tissues, with higher expression levels in the mammary gland, cervix, salivary gland and trachea. The steroid hormone receptor-positive breast cancer cell line BT-474 was used to examine the effect of different steroids on the expression levels of KLK5-SV2. Expression levels were significantly higher after stimulation with androgens, but not estrogens, progestins, aldosterone or corticosteroids. While relatively high levels of expression were found in all 10 normal breast tissues examined, no expression was detected in 16 breast cancer tissues, and expression was significantly lower than normal in the remaining 4 cancers. Expression levels comparable to normal were found in only 1 breast cancer cell line. Weak to no expression was detected in 3 other breast cancer cell lines. KLK5-SV2 was not detectable in any of the 10 normal ovarian tissues examined. It was, however, expressed at relatively high levels in 10 out of 20 ovarian cancer tissues, and lower levels were found in 4 other cancers. No expression was detected in the remaining 6 cancers. High expression levels were also detected in the CAOV-3 ovarian cancer cell line. KLK5-SV2 is a potential biomarker for breast and ovarian cancers.

In silico analysis of the human kallikrein gene 6.

Kallikreins are a family of 15 serine proteases clustered together on the long arm of chromosome 19. Recent reports have linked kallikreins to malignancy. The human kallikrein gene 6 (KLK6) is a newly characterized member of the human kallikrein gene family. Recent work has focused on the possible role of this gene and its protein product as a tumor marker and its involvement in diseases of the central nervous system. In this study, we performed extensive in silico analyses of KLK6 expression from different databases using various bioinformatic tools. These data enabled us to construct and verify the longest transcript for this kallikrein, to identify several polymorphisms among published sequences and to summarize the 21 single-nucleotide polymorphisms of the gene. Our expressed sequence tag (EST) analyses suggest the existence of seven new splice variants of the gene, in addition to the already reported ones. Most of these variants were identified in libraries from cancerous tissues. KLK6 orthologues were identified from three other species with approximately 86% overall homology with rat and mouse orthologues. We also utilized several databases to compare KLK6 gene expression in normal and cancerous tissues. The serial analysis of gene expression and EST expression profiles showed upregulation of the gene in female genital (ovarian and uterine) and gastrointestinal (gastric, colon, esophageal and pancreatic) cancers. Significant downregulation was observed in breast cancers and brain tumors, in relation to their normal counterparts.

Oral and maxillofacial surgery in patients with chronic orofacial pain.

PURPOSE: In this investigation, we evaluated a population of patients with chronic orofacial pain who sought treatment at a pain center in an academic institution. These patients were evaluated with respect to 1) the frequency and types of previous oral and maxillofacial surgery procedures, 2) the frequency of previous significant misdiagnoses, and 3) the number of patients who subsequently required surgical treatment as recommended by an interdisciplinary orofacial pain team. The major goal of this investigation was to determine the role of oral and maxillofacial surgery in patients with chronic orofacial pain. PATIENTS AND METHODS: The study population included patients seen at the Center for Oral, Facial and Head Pain at New York Presbyterian Hospital from January 1999 through April 2001. (120 patients; female-to-male ratio, 3:1; mean age, 49 years; average pain duration, 81 months; average number of previous specialists, 6). The patient population was evaluated by an interdisciplinary orofacial pain team and the following characteristics of this population were profiled: 1) the frequency and types of previous surgical procedures, 2) diagnoses, 3) the frequency of previous misdiagnoses, and 4) treatment recommendations made by the center team. RESULTS: There was a history of previous oral and maxillofacial surgical procedures in 38 of 120 patients (32%). Procedures performed before our evaluation included endodontics (30%), extractions (27%), apicoectomies (12%), temporomandibular joint (TMJ) surgery (6%), neurolysis (5%), orthognathic surgery (3%), and debridement of bone cavities (2%). Surgical intervention clearly exacerbated pain in 21 of 38 patients (55%) who had undergone surgery. Diagnoses included myofascial pain (50%), atypical facial neuralgia (40%), depression (30%), TMJ synovitis (14%), TMJ osteoarthritis (12%), trigeminal neuralgia (10%), and TMJ fibrosis (2%). Treatment recommendations included medications (91%), physical therapy (36%), psychiatric management (30%), trigger injections (15%), oral appliances (13%), biofeedback (13%), acupuncture (8%), surgery (4%), and Botox injections (1%) (Allergan Inc, Irvine, CA). Gross misdiagnosis leading to serious sequelae, with delay of necessary treatment, occurred in 6 of 120 patients (5%). CONCLUSIONS: Misdiagnosis and multiple failed treatments were common in these patients with chronic orofacial pain. These patients often have multiple diagnoses, requiring management by multiple disciplines. Surgery, when indicated, must be based on a specific diagnosis that is amenable to surgical therapy. However, surgical treatment was rarely indicated as a treatment for pain relief in these patients with chronic orofacial pain, and it exacerbated and perpetuated pain symptoms in some of them.

Prothrombin activation in eastern tiger snake bite.

AIMS: To perform ex vivo studies in eastern tiger snake envenomation which define the haemostatic events associated with prothrombin activation. METHOD: Serial studies were performed on plasma from six individuals with evidence of eastern tiger snake envenomation. These analyses were particularly directed to fibrinogen levels, F1 + 2, TAT and evidence of fibrinolysis. RESULTS: There was a substantial rise in F1 + 2 and thrombin-antithrombin (TAT) complexes in all cases, even with minimal evenomation. In some cases the molar ratio of F1 + 2 and TAT was reduced from the relationship normally seen in vitro and ex vivo in clinical thrombosis. There was a dramatic fall in factor V and VIII levels which occurred 4-6 hours before the decline in prothrombin and AT3. This related in time to a fall in alpha2AP and plasminogen. Protein C levels also declined dramatically but many hours after presentation. CONCLUSIONS: F1 + 2 and TAT are sensitive markers of tiger snake evenomation. In some patients with massive prothrombin activation, the common mechanism for TAT clearance may be altered or overwhelmed. Conversely, the renal clearance of the smaller F1 + 2 may be enhanced. In the absence of thrombocytopaenia, which is a very sensitive marker of DIC, the fall in labile factors with tiger snake envenomation is significantly contributed to by proteolytic digestion of clotting factors.

Grenada national population report

Presents an outline of the status of the population of Grenada, including the main population/development concerns, the institutional mechanisms in place, and plans and programmes to incorporate population into the development planning process. Population growth is identified as the main stimulus and at times, an obstacle to economic growth. However, it is widely agreed that policy decisions should reflect a pragmatic approach in dealing with population/development issues. It is also recognised that higher population growth increases pressure on the provision of basic services, the use of space and natural resources, and the environment. The quality of human resources for development, is of equal importance, but can be hindered by significant population increases