Research ethics and artificial intelligence for global health: perspectives from the global forum on bioethics in research.

BACKGROUND: The ethical governance of Artificial Intelligence (AI) in health care and public health continues to be an urgent issue for attention in policy, research, and practice. In this paper we report on central themes related to challenges and strategies for promoting ethics in research involving AI in global health, arising from the Global Forum on Bioethics in Research (GFBR), held in Cape Town, South Africa in November 2022. METHODS: The GFBR is an annual meeting organized by the World Health Organization and supported by the Wellcome Trust, the US National Institutes of Health, the UK Medical Research Council (MRC) and the South African MRC. The forum aims to bring together ethicists, researchers, policymakers, research ethics committee members and other actors to engage with challenges and opportunities specifically related to research ethics. In 2022 the focus of the GFBR was "Ethics of AI in Global Health Research". The forum consisted of 6 case study presentations, 16 governance presentations, and a series of small group and large group discussions. A total of 87 participants attended the forum from 31 countries around the world, representing disciplines of bioethics, AI, health policy, health professional practice, research funding, and bioinformatics. In this paper, we highlight central insights arising from GFBR 2022. RESULTS: We describe the significance of four thematic insights arising from the forum: (1) Appropriateness of building AI, (2) Transferability of AI systems, (3) Accountability for AI decision-making and outcomes, and (4) Individual consent. We then describe eight recommendations for governance leaders to enhance the ethical governance of AI in global health research, addressing issues such as AI impact assessments, environmental values, and fair partnerships. CONCLUSIONS: The 2022 Global Forum on Bioethics in Research illustrated several innovations in ethical governance of AI for global health research, as well as several areas in need of urgent attention internationally. This summary is intended to inform international and domestic efforts to strengthen research ethics and support the evolution of governance leadership to meet the demands of AI in global health research.

Towards a new model of global health justice: the case of COVID-19 vaccines.

This paper questions an exclusively state-centred framing of global health justice and proposes a multilateral alternative. Using the distribution of COVID-19 vaccines to illustrate, we bring to light a broad range of global actors up and down the chain of vaccine development who contribute to global vaccine inequities. Section 1 (Background) presents an overview of moments in which diverse global actors, each with their own priorities and aims, shaped subsequent vaccine distribution. Section 2 (Collective action failures) characterises collective action failures at each phase of vaccine development that contributed to global vaccine disparities. It identifies as critical the task of establishing upstream strategies to coordinate collective action at multiple stages across a range of actors. Section 3 (A Multilateral model of global health governance) takes up this task, identifying a convergence of interests among a range of stakeholders and proposing ways to realise them. Appealing to a responsibility to protect (R2P), a doctrine developed in response to human rights atrocities during the 1990s, we show how to operationalise R2P through a principle of subsidiarity and present ethical arguments in support of this approach.

Acute uterine inversion following an induced abortion.

Acute uterine inversion is a rare and potentially life-threatening obstetric emergency. Its occurrence as a result of a mid-trimester abortion is an even rarer consequence. We report a case of a 32-year-old woman who presented with complete acute uterine inversion and hemorrhagic shock following an incomplete medical abortion at 14 weeks of gestation. Our attempts at non-operative reversal of the inversion failed. Therefore, we resorted to the manual replacement of the uterus via laparotomy without using surgical instruments or an incision in the cervical ring. The laparotomic manual replacement served as a successful alternative with minimal immediate or long-term morbidity that may have resulted from trauma and scarring of the uterus.

Photoacoustic monitoring of angiogenesis predicts response to therapy in healing wounds.

Chronic wounds are a major health problem that cause the medical infrastructure billions of dollars every year. Chronic wounds are often difficult to heal and cause significant discomfort. Although wound specialists have numerous therapeutic modalities at their disposal, tools that could three dimensional-map wound bed physiology and guide therapy do not exist. Visual cues are the current standard but are limited to surface assessment; clinicians rely on experience to predict response to therapy. Photoacoustic (PA) ultrasound (US) is a non-invasive, hybrid imaging modality that can solve these major limitations. PA relies on the contrast generated by haemoglobin in blood which allows it to map local angiogenesis, tissue perfusion and oxygen saturation-all critical parameters for wound healing. This work evaluates the use of PA-US to monitor angiogenesis and stratify patients responding versus not-responding to therapy. We imaged 19 patients with 22 wounds once a week for at least 3 weeks. Our findings suggest that PA imaging directly visualises angiogenesis. Patients responding to therapy showed clear signs of angiogenesis and an increased rate of PA increase (p = 0.002). These responders had a significant and negative correlation between PA intensity and wound size. Hypertension was correlated to impaired angiogenesis in non-responsive patients. The rate of PA increase and hence the rate of angiogenesis was able to predict healing times within 30 days from the start of monitoring (power = 88%, alpha = 0.05). This early response detection system could help inform management and treatment strategies while improving outcomes and reducing costs.

Global sharing of COVID-19 therapies during a "New Normal".

This paper argues for global sharing of COVID-19 treatments during the COVID-19 pandemic and beyond based on principles of global solidarity. It starts by distinguishing two types of COVID-19 treatments and models sharing strategies for each in small-group scenarios, contrasting groups that are solidaristic with those composed of self-interest maximizers to show the appeal of solidaristic reasoning. It then extends the analysis, arguing that a similar logic should apply within and between nations. To further elaborate global solidarity, the paper distinguishes morally voluntary, sliding-scale, and mandatory versions. It argues for an all-hands-on-deck approach and gives examples to illustrate. The paper concludes that during the COVID-19 crisis, global solidarity is a core value, and global sharing of COVID-19 treatments should be considered a duty of justice, not of charity.

What's yours is ours: waiving intellectual property protections for COVID-19 vaccines.

This paper gives an ethical argument for temporarily waiving intellectual property (IP) protections for COVID-19 vaccines. It examines two proposals under discussion at the World Trade Organization (WTO): the India/South Africa proposal and the WTO Director General proposal. Section I explains the background leading up to the WTO debate. Section II rebuts ethical arguments for retaining current IP protections, which appeal to benefiting society by spurring innovation and protecting rightful ownership. It sets forth positive ethical arguments for a temporary waiver that appeal to standing in solidarity and holding companies accountable. After examining built-in exceptions to existing agreements and finding them inadequate, the paper replies to objections to a temporary waiver and concludes, in section III, that the ethical argument for temporarily waiving IP protection for COVID-19 vaccines is strong.

Articulating the sources for an African normative framework of healthcare: Ghana as a case study.

Bioethics is gradually becoming an important part of the drive to increase quality healthcare delivery in sub-Saharan African countries. Yet many healthcare service-users in Africa are familiar with incidences of questionable health policies and poor healthcare delivery, leading to severe consequences for patients. We argue that the overarching rights-based ethical administrative framework recently employed by healthcare authorities contributes to the poor uptake and enforcement of current normative tools. Taking Ghana as a case study, we focus on the cultural ethical context and we tease out the concepts of the good and the ethical among the Akan and Bulsa ethnic groups. We point out three tenets towards building a normative framework that can resonate with service-users and practitioners: ontological communitarianism; empathic humanism; and virtuous character. Finally, we indicate how these core tenets can be dovetailed into building an effective normative framework and into the training of healthcare providers.

A uniform method for the simultaneous blood group phenotyping of Fya , Fyb , Jka , Jkb , S, sÌ , P1, k applying lateral-flow technique.

BACKGROUND AND OBJECTIVES: A lateral flow assay for simultaneous blood group typing of ABO, RhD, C, E, c, e, Cw and K with stable end-point and without centrifugation is in routine use since several years (MDmulticard® ). The typing of extended phenotype parameters belonging to the Duffy, Kidd, MNSs blood group systems and others, however, has not yet been demonstrated for this technique. Reliable detection of Fyx , a weak Fyb phenotype with a pronounced quantitative reduction of the number of Fyb antigens on the erythrocyte surface, remains a weakness of current serological blood grouping techniques. MATERIAL AND METHODS: The performance characteristics of the following reagents were evaluated in donor and patient samples in lateral flow technology (MDmulticard® ): Anti-Fya , -Fyb , -Jka , -Jkb , -S, -s̅, -P1 and -k. The sensitivity to detect Fyx was in addition evaluated with Fyx positive samples, which had been preselected by MALDI-TOF MS-based genotyping. RESULTS: All results obtained with the MDmulticard® were in full accordance with those of the CE-certified reference products for all the eight reagent formulations used: Anti-Fya , -Fyb , -Jka , -Jkb , -S, -s̅, -P1 and -k. Also, all Fyx phenotypes of the selected population of 93 positive samples, originally identified by MALDI-TOF MS-based genotyping, were reliably detected by the lateral flow assay. CONCLUSION: Extended phenotype blood group parameters, including the serologically challenging Fyx phenotype, can be determined simultaneously, rapidly and accurately using the lateral flow (MDmulticard® ) technology, even in cases when IgG class antibodies are the only source of diagnostic antibodies.

First Report of Rhizoctonia spp. Causing a Root Rot of the Invasive Rangeland Weed Lepidium draba in North America.

The exotic, invasive perennial rangeland weed Lepidium draba spreads rapidly and reduces native species diversity. The extensive root system of L. draba constitutes 76% of its biomass (4). Thus, searches have been done for biocontrol agents that target root tissue or that may interact with a weevil, Ceutorhynchus assimilis, that causes galls in the crown area of L. draba. An association of Rhizoctonia spp. with root tissue of plants galled by the weevil has been documented in Europe (3). The possible presence of soilborne pathogens similar to those found in the native range has been the subject of L. draba surveys in the United States. One such survey in 2008 detected a few plants with reddened and chlorotic foliage in a stand near Shepherd, MT. Such symptoms typically indicate the occurrence of soilborne diseases on L. draba in the native range of the weed (2). The site had shown a gradual increase in the range of detectable pathogens beginning with foliar pathogens in 1997. In 2010, at the Shepherd site, L. draba plants with similar (but more severe) symptoms to those seen in 2008 were noted in a different area of the stand. Excavation of the roots in both years revealed brown, sunken crown and root cankers. Pieces of root tissue were excised from the lesions and plated on acidified PDA and Ko and Hora medium. A non-sporulating fungus was isolated from three plants. Colonies of the isolates on PDA were typical of known Rhizoctonia spp. The 2010 isolates were determined to be multinucleate using DAPI and were paired with 14 tester (including subgroups) isolates of AG-1 to AG-4 on water agar. Anastomosis was observed between the multinucleate isolates and the AG-2-1 tester isolate. Sequence analysis of ITS of the rDNA of a multinucleate isolate (GenBank KJ545577) indicated 99% similarity with an accession of R. solani AG 2-1 (AB547381). The 2008 isolates were binucleate. A binucleate isolate, KJ545578, had 100% similarity with an isolate of Rhizoctonia spp. AG-A (AY927356). Pathogenicity tests consisted of planting 6-week-old seedlings of L. draba, one per pot, in ten 85-cm-diameter pots of pasteurized soil mix infested with Rhizoctonia-colonized barley grain that had been dried and milled. An inoculum level of ~8 CFU/g (1) of air-dried soil was established by most probable number calculations from fourfold dilutions of infested soil. Controls were the same number of plants in pasteurized potting mix. Results were recorded after 3 months in a greenhouse at 20-25°C. The test was repeated. Typically, R. solani caused mortality of six to eight plants, from which it was re-isolated, whereas binuclate isolates caused stunting and lower dry weight of L. draba. Control plants remained asymptomatic. This is the first report of R. solani and binucleate Rhizoctonia spp. on L. draba in North America. References: (1) A. J. Caesar et al. Plant Dis. 93:1350, 2009. (2) A. J. Caesar et al. Biol. Control 52:140, 2010. (3) A. J. Caesar et al. Plant Dis. 96:145, 2011. (4) R. F. Miller et al. Agronomy J. 86:487, 1994.

Artificial Intelligence in Military Medicine.

Artificial intelligence (AI) has garnered significant attention for its pivotal role in the national security and health care sectors. However, its utilization in military medicine remains relatively unexplored despite its immense potential. AI operates through evolving algorithms that process extensive datasets, continuously improving accuracy and emulating human learning processes. Generative AI, a type of machine learning, uses algorithms to generate new content, such as images, text, videos, audio, and computer code. These models employ deep learning to encode simplified representations of training data and generate new work resembling the original without being identical. Although many AI applications in military medicine are theoretical, the U.S. Military has implemented several initiatives, often without widespread awareness among its personnel. This article aims to shed light on two resilience initiatives spearheaded by the Joint Artificial Intelligence Center, which is now the Chief Digital and Artificial Intelligence Office. These initiatives aim to enhance commanders' dashboards for predicting troop behaviors and develop models to forecast troop suicidality. Additionally, it outlines 5 key AI applications within military medicine, including (1) clinical efficiency and routine decision-making support, (2) triage and clinical care algorithms for large-scale combat operations, (3) patient and resource movements in the medical common operating picture, (4) health monitoring and biosurveillance, and (5) medical product development. Even with its promising potential, AI brings forth inherent risks and limitations that require careful consideration and discussion. The article also advocates for a forward-thinking approach for the U.S. Military to effectively leverage AI in advancing military health and overall operational readiness.

Competition-driven eco-evolutionary feedback reshapes bacteriophage lambda's fitness landscape and enables speciation.

A major challenge in evolutionary biology is explaining how populations navigate rugged fitness landscapes without getting trapped on local optima. One idea illustrated by adaptive dynamics theory is that as populations adapt, their newly enhanced capacities to exploit resources alter fitness payoffs and restructure the landscape in ways that promote speciation by opening new adaptive pathways. While there have been indirect tests of this theory, to our knowledge none have measured how fitness landscapes deform during adaptation, or test whether these shifts promote diversification. Here, we achieve this by studying bacteriophage [Formula: see text], a virus that readily speciates into co-existing receptor specialists under controlled laboratory conditions. We use a high-throughput gene editing-phenotyping technology to measure [Formula: see text]'s fitness landscape in the presence of different evolved-[Formula: see text] competitors and find that the fitness effects of individual mutations, and their epistatic interactions, depend on the competitor. Using these empirical data, we simulate [Formula: see text]'s evolution on an unchanging landscape and one that recapitulates how the landscape deforms during evolution. [Formula: see text] heterogeneity only evolves in the shifting landscape regime. This study provides a test of adaptive dynamics, and, more broadly, shows how fitness landscapes dynamically change during adaptation, potentiating phenomena like speciation by opening new adaptive pathways.

First Report of Spot Form Net Blotch Caused by Pyrenophora teres f. maculata on Barley in the Mon-Dak Area of the United States.

Pyrenophora teres Drechs. causes net blotch of barley, a common foliar disease in cultivation zones around the world. The disease occurs in two forms, namely a net form net blotch (NFNB) caused by P. teres f. teres and a spot form net blotch (SFNB) caused by P. teres f. maculata. As in other parts of the northern Great Plains, in the Mon-Dak area (western North Dakota and eastern Montana), NFNB is prevalent. SFNB was first reported in western Montana in 1983 (1) and more recently in eastern North Dakota in 2010 (3) but not in the Mon-Dak area. In the summer of 2011, unusual spot lesions that were surrounded by necrosis or chlorosis were observed on different barley cultivars in fields at Williston, ND, Nesson Valley, ND, and Sidney, MT areas. Diseased leaves from various barley cvs. from the three locations were transferred to water agar and incubated at room temperature for 24 h to induce sporulation. Morphological examination of conidia (45 to 169 × 15 to 21 µm) did not show significant differences from a known isolate of P. teres f. teres 0-1 (provided by Tim Friesen, ARS, Fargo, ND). For pathogenicity testing, six 14-day-old plants of barley cv. Tradition were sprayed until runoff with a 2,000 spore/ml suspension of two isolates from each location and the control P. teres f. maculata isolate DEN2.6 (provided by Tim Friesen). Plants were incubated first in a lighted humidity chamber for 24 h and then in a greenhouse for 7 days at 21°C. Regardless of inoculum source, spot lesions surrounded by necrosis or chlorosis, typical of SFNB, appeared on the inoculated leaves within 7 days. Fungi isolated from symptomatic leaves were identified as P. teres and the morphology of the conidia was undistinguishable from those of P. teres f. teres. All control plants which were sprayed with sterile distilled water were symptomless. The pathogenicity test was repeated. Rapid PCR detection and amplicon sequencing (2) of the internal transcribed spacer (ITS) region of ribosomal genes was performed on field and pathogenicity test leaf lesion samples to confirm the presence of P. teres f. maculata. DNA templates were prepared using the Extract-N-Amp Plant PCR Kits (Sigma Chemical Co., St. Louis, MO) and subjected to PCR using ITS1 and ITS4 primers. Amplicons were then purified and sequenced. The 585-bp nucleotide sequences of P. teres f. maculata from Mon-Dak area were submitted to GenBank under accession nos. PtmNES1 (JX187587), PtmSDY1 (JX187588), PtmSDY2 (JX187589), and PtmWIL1 (JX187590). The sequences from the four locations shared 100% similarity and also with P. teres f. maculata (EF452471) from GenBank while showing 10 nucleotide differences (99% similarity) with P. teres f. teres (EF452472).The results represent first report of SFNB in the Mon-Dak. Barley is one of the most important crops in the area. Resistance of the NFNB and SFNB of barley are controlled by different genes (4). Based on this report, SFNB therefore have to be considered in selection of barley cultivars for cultivation in the area. References: (1) H. E Bockelman et al. Plant Dis. 67:696, 1983. (2) R. T. Lartey et al. J. Sugar Beet Res. 40:1, 2003. (3) Z. H. Liu and T. L. Friesen. Plant Dis. 94:480, 2010. (4) O. M. Manninen et al. Genome. 46:1564, 2006.

Equitable global allocation of monkeypox vaccines.

With the world grappling with continued spread of monkeypox internationally, vaccines play a crucial role in mitigating the harms from infection and preventing spread. However, countries with the greatest need - particularly historically endemic countries with the highest monkeypox case-fatality rates - are not able to acquire scarce vaccines. This is unjust, and requires rectification through equitable allocation of vaccines globally. We propose applying the Fair Priority Model for such allocation, which emphasizes three key principles: 1) preventing harm; 2) prioritizing the disadvantaged; and 3) treating people with equal moral concern. Post-exposure prophylaxis (PEPV) has the most potential to mitigate harm, and so ensuring countries have sufficient supply for PEPV should be the first priority. And historically endemic countries, which face disadvantages that compound potential harms from monkeypox, should be the first recipients of such vaccines. Once sufficient supply is allocated for countries to apply PEPV, global allocation could move on to pre-exposure prophylaxis (PrEP), again prioritizing historically endemic countries first before distribution to the rest of the global community, based on projected number of cases and vulnerability to harm.

The importance of getting the ethics right in a pandemic treaty.

The COVID-19 pandemic revealed numerous weaknesses in pandemic preparedness and response, including underfunding, inadequate surveillance, and inequitable distribution of countermeasures. To overcome these weaknesses for future pandemics, WHO released a zero draft of a pandemic treaty in February, 2023, and subsequently a revised bureau's text in May, 2023. COVID-19 made clear that pandemic prevention, preparedness, and response reflect choices and value judgements. These decisions are therefore not a purely scientific or technical exercise, but are fundamentally grounded in ethics. The latest treaty draft reflects these ethical considerations by including a section entitled Guiding Principles and Approaches. Most of these principles are ethical-they establish core values that undergird the treaty. Unfortunately, the treaty draft's set of principles are numerous, overlapping, and show inadequate coherence and consistency. We propose two improvements to this section of the draft pandemic treaty. First, key guiding ethical principles should be clearer and more precise than they currently are. Second, the link between ethical principles and policy implementation should be clearly established and define boundaries on acceptable interpretation, ensuring that signatories abide by these principles.

Competition-driven eco-evolutionary feedback reshapes bacteriophage lambda's fitness landscape and enables speciation.

A major challenge in evolutionary biology is explaining how populations navigate rugged fitness landscapes without getting trapped on local optima. One idea illustrated by adaptive dynamics theory is that as populations adapt, their newly enhanced capacities to exploit resources alter fitness payoffs and restructure the landscape in ways that promote speciation by opening new adaptive pathways. While there have been indirect tests of this theory, none have measured how fitness landscapes deform during adaptation, or test whether these shifts promote diversification. Here, we achieve this by studying bacteriophage λ, a virus that readily speciates into co-existing receptor specialists under controlled laboratory conditions. We used a high-throughput gene editing-phenotyping technology to measure λ's fitness landscape in the presence of different evolved-λ competitors and found that the fitness effects of individual mutations, and their epistatic interactions, depend on the competitor. Using these empirical data, we simulated λ's evolution on an unchanging landscape and one that recapitulates how the landscape deforms during evolution. λ heterogeneity only evolved in the shifting landscape regime. This study provides a test of adaptive dynamics, and, more broadly, shows how fitness landscapes dynamically change during adaptation, potentiating phenomena like speciation by opening new adaptive pathways.

Bi-fluorescence imaging for estimating accurately the nuclear condition of Rhizoctonia spp.

AIMS: To simplify the determination of the nuclear condition of the pathogenic Rhizoctonia, which currently needs to be performed either using two fluorescent dyes, thus more costly and time-consuming, or using only one fluorescent dye, thus less accurate. METHODS AND RESULTS: A red primary fluorescence (autofluorescence) of the hyphal cell walls and septa of Rhizoctonia spp. with green excitation is evidenced in Rhizoctonia spp. This property is exploited and combined for the first time with a conventional DAPI fluorescence to accurately determine the nuclear condition of Rhizoctonia. This bi-fluorescence imaging strategy depicted the nuclear condition in Rhizoctonia spp. more accurately than the conventional DAPI fluorescence used alone and was validated against isolates previously genotyped by DNA sequencing. CONCLUSIONS: We demonstrated that the bi-fluorescence imaging strategy was safe, accurate and simple to perform and interpret. SIGNIFICANCE AND IMPACT OF THE STUDY: The developed bi-fluorescence imaging strategy provides a sensitive tool for determining the nuclear condition of Rhizoctonia strains. Its simplicity is a key advantage when there are numerous cultures to be examined.

First Report of a Root and Crown Disease of the Invasive Weed Lepidium draba Caused by Phoma macrostoma.

The exotic rangeland perennial Lepidium draba occurs as a noxious weed in 22 states, mostly in the western United States. Because chemical control measures against this invasive perennial, a member of the Brassicaceae, have not achieved adequate results, biological control is being pursued. While inventories of arthropods that feed on L. draba have been established, little is known of soilborne pathogens for possible use as biological control agents. To address this deficiency, we have surveyed for diseases of L. draba in the United States and Eurasia to identify and test potential biocontrol agents. In intensive surveys for soilborne diseases in a single infestation that is >20 years old in a cattle pasture in south-central Montana, several chlorotic, stunted plants were noted. Roots of chlorotic plants that exhibited elongated fissures from which other soilborne fungi were isolated also had numerous prominent pycnidia embedded in the crown tissue above the lesions. Examination with a dissecting microscope revealed large ostioles made evident by the wide concave inversions in the short necks of the pycnidia. Culture of root tissue on potato dextrose agar resulted in whitish, becoming pale gray colonies, with a dull peach-to-reddish tinge at the margins, with abundant single pycnidia. Conidia in vitro were mainly unicellular, variable shape, subglobose to ellipsoidal, with several guttules averaging 6 × 2.5 µm. These morphological traits are characteristic of Phoma macrostoma, which is regarded as a weak or wound pathogen. The internal transcribed spacer region of rDNA was amplified using primers ITS1 and ITS4 and sequenced. BLAST analysis of the 575-bp fragment showed a 100% homology with the sequence of an isolate of P. macrostoma that has been investigated extensively for commercialization as a biological control agent of various agricultural weeds (1), including wild mustard (GenBank No. DQ474091). The nucleotide sequence has been assigned GenBank No. HM755951. Pathogenicity tests consisted of making four 1.4-mm-diameter holes in five NaOCl (0.1%)-sterilized root sections of L. draba and pipetting ~50 to 100 µl of a 106 CFU/ml conidial suspension into the incisions, incubating the inoculated roots at 20 to 25°C overnight and planting the root sections, one per pot, in an artificial greenhouse potting mix and placing the pots in the greenhouse at 20 to 25°C. Controls were five root sections that were treated similarly except that sterile water was injected. The experiment was repeated. After 10 days, shoots that grew from inoculated roots were chlorotic and shorter than those produced from control roots. P. macrostoma was isolated from tissue of inoculated roots that became blackened distal to the inoculation points. To examine the host range of P. macrostoma on other brassica species, crowns of 2-week-old seedlings of radish, broccoli, cauliflower, broccoli raab, turnip, kohlrabi, cabbage, Chinese cabbage, mustard greens, and canola were injected with 0.5 ml of a 106 CFU/ml conidial suspension. Plants were grown in the greenhouse at 20 to 25°C for 4 weeks after inoculation and examined for symptoms. The experiment was repeated twice. Blackened root tissue with slight chlorosis occurred only on roots of radish and crowns of broccoli, from which P. macrostoma was reisolated. To our knowledge, this the first report of a disease of L. draba caused by P. macrostoma. Reference: (1) K. L. Bailey et al. U.S. Patent Application Serial No. 60/294,475, Filed May 20, 2001.

Photoacoustic imaging to monitor outcomes during hyperbaric oxygen therapy: validation in a small cohort and case study in a bilateral chronic ischemic wound.

Hyperbaric oxygen therapy (HBO2) is a common therapeutic modality that drives oxygen into hypoxic tissue to promote healing. Here, ten patients undergoing HBO2 underwent PA oximetry of the left radial artery and forearm pre- and post-HBO2; this cohort validated the use of PA imaging in HBO2. There was a significant increase in radial artery oxygenation after HBO2 (p = 0.002) in the validation cohort. We also include a case study: a non-diabetic male in his 50s (HB 010) presenting with bilateral ischemic and gangrenous wounds. HB 010 showed higher perfusion and oxygen saturation on the right foot than the left after HBO2 which correlated with independent surgical observations. Imaging assisted with limb salvage treatment. Hence, this work shows that PA imaging can measure changes in arterial oxygen saturation due to HBO2; it can also produce 3D maps of tissue oxygenation and evaluate response to therapy during HBO2.

Mechanism of action of an imidopiperidine inhibitor of human polynucleotide kinase/phosphatase.

The small molecule, 2-(1-hydroxyundecyl)-1-(4-nitrophenylamino)-6-phenyl-6,7a-dihydro-1H-pyrrolo[3,4-b]pyridine-5,7(2H,4aH)-dione (A12B4C3), is a potent inhibitor of the phosphatase activity of human polynucleotide kinase/phosphatase (PNKP) in vitro. Kinetic analysis revealed that A12B4C3 acts as a noncompetitive inhibitor, and this was confirmed by fluorescence quenching, which showed that the inhibitor can form a ternary complex with PNKP and a DNA substrate, i.e. A12B4C3 does not prevent DNA from binding to the phosphatase DNA binding site. Conformational analysis using circular dichroism, UV difference spectroscopy, and fluorescence resonance energy transfer all indicate that A12B4C3 disrupts the secondary structure of PNKP. Investigation of the potential site of binding of A12B4C3 to PNKP using site-directed mutagenesis pointed to interaction between Trp(402) of PNKP and the inhibitor. Cellular studies revealed that A12B4C3 sensitizes A549 human lung cancer cells to the topoisomerase I poison, camptothecin, but not the topoisomerase II poison, etoposide, in a manner similar to small interfering RNA against PNKP. A12B4C3 also inhibits the repair of DNA single and double strand breaks following exposure of cells to ionizing radiation, but does not inhibit two other key strand-break repair enzymes, DNA polymerase beta or DNA ligase III, providing additional evidence that PNKP is the cellular target of the inhibitor.