自家受精魚マングローブキリフィッシュ（Kryptolebias marmoratus）の生殖腺の形態

We conducted anatomical and histological observations of the gonads in the self-fertilizing mangrove killifish, Kryptolebias marmoratus to investigate the self-fertilizing mechanism of this species. The gonad has a bilobed structure. The elongated gonadal lumen (GL) along the dorsal surface of the gonad connects to the common genital sinus. The elongate testicular region is closely attached to the GL. Among the ovulated eggs in the GL, those in the anterior part of the GL have micropyles but no perivitelline space (are not yet fertilized), whereas those in the posterior part of the GL are fertilized. In our histological analysis, we found free sperm in the posterior area of the GL. We conclude that ovulated eggs may be self-fertilized in the posterior GL.マングローブキリフィッシュ（Kryptolebias marmoratus）の生殖腺の解剖学および組織学的な観察を行い，本種の自家受精機構を考察した。生殖腺は二葉に分かれ，生殖管は生殖腺背面を通り泌尿生殖口へ達した。精巣組織は生殖管に隣接していた。生殖管内に排卵された卵のうち，生殖管前方の卵には囲卵腔がなく卵門を有しており未受精であったが，生殖管後方の卵は受精していた。組織学的観察から，生殖管後方で排精の起こっていることが明らかとなった。排卵後に卵が生殖管を通る段階で自家受精が起こると考えられた

Alkali Metal Complexes of Phosphine-Borane-Substituted Benzyl Ligands and Their Application in the Synthesis of B-H\ub7\ub7\ub7Sn Stabilized Dialkylstannylenes

\ua9 2024 The Authors. Published by American Chemical Society.The benzyl-substituted phosphine-boranes PhCH2P(BH3)R2 [R = iPr (1H), Ph (2H), Cy (3H)] are accessible through either the reaction between R2PCl and PhCH2MgBr, followed by treatment with BH3\ub7SMe2 or the reaction between R2P(BH)3Li and PhCH2Br. Treatment of 1H, 2H, or 3H with nBuLi, PhCH2Na, or PhCH2K gave the corresponding alkali metal complexes [{iPr2P(BH3)CHPh}Li(THF)]2 (1Li), [{Ph2P(BH3)CHPh}Li(OEt2)2] (2Li), [{Cy2P(BH3)CHPh}Li(TMEDA)] (3Li), [iPr2P(BH3)CHPh]Na (1Na), [{Ph2P(BH3)CHPh}Na(THF)2]2 (2Na), [Cy2P(BH3)CHPh]Na(THF)0.5 (3Na), [{iPr2P(BH3)CHPh}K]∞ (1K), [{Ph2P(BH3)CHPh}K(THF)]∞ (2K), and [{Cy2P(BH3)CHPh}K.0.5PhMe]∞ (3K). X-ray crystallography revealed that, while 2Li and 3Li crystallize as monomers, 1Li and 2Na crystallize as borane-bridged dimers. The potassium complexes 1K, 2K, and 3K all crystallize with polymeric structures, in which the monomer units are linked to each other through a range of both bridging BH3 groups and multihapto interactions between the potassium cations and the aromatic rings. The reactions between two equivalents of either 1Li or 3Li and Cp2Sn gave the corresponding dialkylstannylenes [{R2P(BH3)CHPh}2Sn] [R = iPr (1Sn), Cy (3Sn)]. These compounds were isolated as mixtures of the rac and meso diastereomers. X-ray crystallography reveals that rac-1Sn and rac-3Sn crystallize as discrete monomers each exhibiting two agostic-type B-H\ub7\ub7\ub7Sn contacts

The effect of monthly sulfadoxine-pyrimethamine, alone or with azithromycin, on pcr-diagnosed malaria at delivery: A randomized controlled trial

10.1371/journal.pone.0041123PLoS ONE77

The cost of uncomplicated childhood fevers to Kenyan households: implications for reaching international access targets

BACKGROUND: Fever is the clinical hallmark of malaria disease. The Roll Back Malaria (RBM) movement promotes prompt, effective treatment of childhood fevers as a key component to achieving its optimistic mortality reduction goals by 2010. A neglected concern is how communities will access these new medicines promptly and the costs to poor households when they are located in rural areas distant to health services. METHODS: We assemble data developed between 2001 and 2002 in Kenya to describe treatment choices made by rural households to treat a child's fever and the related costs to households. Using a cost-of-illness approach, we estimate the expected cost of a childhood fever to Kenyan households in 2002. We develop two scenarios to explore how expected costs to households would change if more children were treated at a health care facility with an effective antimalarial within 48 hours of fever onset. RESULTS: 30% of uncomplicated fevers were managed at home with modern medicines, 38% were taken to a health care facility (HCF), and 32% were managed at home without the use of modern medicines. Direct household cash expenditures were estimated at $0.44 per fever, while the total expected cost to households (cash and time) of an uncomplicated childhood fever is estimated to be$1.91. An estimated mean of 1.42 days of caretaker time devoted to each fever accounts for the majority of household costs of managing fevers. The aggregate cost to Kenyan households of managing uncomplicated childhood fevers was at least $96 million in 2002, equivalent to 1.00$1.86 because caretakers also save time with prompt treatment if the child has malaria. CONCLUSION: The management of uncomplicated childhood fevers imposes substantial costs on Kenyan households. Achieving substantial improvements in the numbers of fevers treated within 48 hours at a HCF with an effective antimalarial drug (Scenario 1) will not impose additional costs on households. Achieving additional improvements in fevers treated promptly at a HCF (Scenario 2) will impose additional costs on some households roughly equal to average cash expenses for transportation to a HCF. Additional financing mechanisms that further reduce the costs of accessing care at a HCF and/or that make artemisinin-based combination therapies (ACTs) accessible for home management need to be developed and evaluated as a top priority

Research workshop to research work: initial steps in establishing health research systems on Malaita, Solomon Islands

<p>Abstract</p> <p>Introduction</p> <p>Atoifi Adventist Hospital is a 90 bed general hospital in East Kwaio, Malaita, Solomon Islands providing services to the population of subsistence villagers of the region. Health professionals at the hospital and attached College of Nursing have considerable human capacity and willingness to undertake health research. However they are constrained by limited research experience, training opportunities, research systems, physical infrastructure and access to resources. This brief commentary describes an 'Introduction to Health Research' workshop delivered at Atoifi Adventist Hospital in September 2009 and efforts to move from 'research workshop' to 'research work'.</p> <p>The Approach</p> <p>Using a participatory-action research approach underpinned by decolonising methodologies, staff from Atoifi Adventist Hospital and James Cook University (Queensland, Australia) collaboratively designed, implemented and evaluated a health research workshop. Basic health research principles and methods were presented using active learning methodologies. Following the workshop, Atoifi Adventist Hospital and Atoifi College of Nursing staff, other professionals and community members reported an increased awareness and understanding of health research. The formation of a local Research Committee, improved ethics review procedures and the identification of local research mentors followed the week long workshop. The workshop has acted as a catalyst for research activity, increasing structural and human resource capacity for local health professionals and community leaders to engage in research.</p> <p>Discussion and Conclusions</p> <p>Participants from a variety of educational backgrounds participated in, and received benefit from, a responsive, culturally and linguistically accessible health research workshop. Improving health research systems at a remote hospital and aligning these with local and national research agendas is establishing a base to strengthen public health research and practice on Malaita, Solomon Islands.</p

How South Pacific mangroves may respond to predicted climate change and sea level rise

In the Pacific islands the total mangrove area is about 343,735 ha, with largest areas in Papua New Guinea, Solomon Islands, Fiji and New Caledonia. A total of 34 species of mangroves occur, as well as 3 hybrids. These are of the Indo-Malayan assemblage (with one exception), and decline in diversity from west to east across the Pacific, reaching a limit at American Samoa. Mangrove resources are traditionally exploited in the Pacific islands, for construction and fuel wood, herbal medicines, and the gathering of crabs and fish. There are two main environmental settings for mangroves in the Pacific, deltaic and estuarine mangroves of high islands, and embayment, lagoon and reef flat mangroves of low islands. It is indicated from past analogues that their close relationship with sea-level height renders these mangrove swamps particularly vulnerable to disruption by sea-level rise. Stratigraphic records of Pacific island mangrove ecosystems during sea-level changes of the Holocene Period demonstrate that low islands mangroves can keep up with a sea-level rise of up to 12 cm per 100 years. Mangroves of high islands can keep up with rates of sea-level rates of up to 45 cm per 100 years, according to the supply of fluvial sediment. When the rate of sea-level rise exceeds the rate of accretion, mangroves experience problems of substrate erosion, inundation stress and increased salinity. Rise in temperature and the direct effects of increased CO2 levels are likely to increase mangrove productivity, change phenological patterns (such as the timing of flowering and fruiting), and expand the ranges of mangroves into higher latitudes. Pacific island mangroves are expected to demonstrate a sensitive response to the predicted rise in sea-level. A regional monitoring system is needed to provide data on ecosystem changes in productivity, species composition and sedimentation. This has been the intention of a number of programs, but none has yet been implemented

HIV-1 Replication in the Central Nervous System Occurs in Two Distinct Cell Types

Human immunodeficiency virus type 1 (HIV-1) infection of the central nervous system (CNS) can lead to the development of HIV-1-associated dementia (HAD). We examined the virological characteristics of HIV-1 in the cerebrospinal fluid (CSF) of HAD subjects to explore the association between independent viral replication in the CNS and the development of overt dementia. We found that genetically compartmentalized CCR5-tropic (R5) T cell-tropic and macrophage-tropic HIV-1 populations were independently detected in the CSF of subjects diagnosed with HIV-1-associated dementia. Macrophage-tropic HIV-1 populations were genetically diverse, representing established CNS infections, while R5 T cell-tropic HIV-1 populations were clonally amplified and associated with pleocytosis. R5 T cell-tropic viruses required high levels of surface CD4 to enter cells, and their presence was correlated with rapid decay of virus in the CSF with therapy initiation (similar to virus in the blood that is replicating in activated T cells). Macrophage-tropic viruses could enter cells with low levels of CD4, and their presence was correlated with slow decay of virus in the CSF, demonstrating a separate long-lived cell as the source of the virus. These studies demonstrate two distinct virological states inferred from the CSF virus in subjects diagnosed with HAD. Finally, macrophage-tropic viruses were largely restricted to the CNS/CSF compartment and not the blood, and in one case we were able to identify the macrophage-tropic lineage as a minor variant nearly two years before its expansion in the CNS. These results suggest that HIV-1 variants in CSF can provide information about viral replication and evolution in the CNS, events that are likely to play an important role in HIV-associated neurocognitive disorders

Mechanism of action for N-substituted benzamide-induced apoptosis

We have analysed the mechanism of action for induction of apoptosis by N-substituted benzamides using declopramide as a lead compound. We show here that declopramide at doses above 250 μM in the mouse 70Z/3 pre-B cell line or in the human promyeolocytic cancer cell line HL60 induced cytochrome c release into the cytosol and caspase-9 activation. The broad spectrum caspase inhibitor zVADfmk and caspase-9 inhibitor zLEDHfmk inhibited apoptosis and improved cell viability when administrated to cells 1 h before exposure to declopramide, whereas the caspase-8 inhibitor zIEDHfmk had less effect. Also, the over expression of Bcl-2 by transfection in 70Z/3 cells inhibited declopramide-induced apoptosis. Prior to the induction of apoptosis, a G2/M cell cycle block was induced by declopramide. The cell cycle block was also observed in the presence of broad spectrum caspase inhibitor zVADfmk and in a transfectant expressing high levels of Bcl-2. Furthermore, while p53 was induced in 70Z/3 cells by declopramide, neither the apoptotic mechanism nor the G2/M cell cycle block were dependent on p53 activation since both effects were also seen in p53 deficient HL60 cells after addition of declopramide

N-substituted benzamides inhibit NFκB activation and induce apoptosis by separate mechanisms

Benzamides have been in clinical use for many years in treatment against various disorders. A recent application is that as a sensitizer for radio- or chemotherapies. We have here analysed the mechanism of action of N-substituted benzamides using an in vitro system. We found that while procainamide was biologically inert in our system, the addition of a chloride in the 3′ position of the benzamide ring created a compound (declopramide) that induced rapid apoptosis. Furthermore, declopramide also inhibited NFκB activation by inhibition of IκBβ breakdown. An acetylated variant of declopramide, N-acetyl declopramide, showed no effect with regard to rapid apoptosis induction but was a potent inhibitor of NFκB activation. In fact, the addition of an acetyl group to procainamide in the 4′ position was sufficient to convert this biologically inactive substance to a potent inhibitor of NFκB activation. These findings suggest two potential mechanisms, induction of early apoptosis and inhibition of NFκB mediated salvage from apoptosis, for the biological effect of N-substituted benzamides as radio- and chemo-sensitizers. In addition it suggests that N-substituted benzamides are potential candidates for the development of anti-inflammatory compounds using NFκB as a drug target. © 1999 Cancer Research Campaig