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Background: Kiribati, a remote atoll island country of the Pacific, has serious problems of vitamin A deficiency (VAD). Thus, it is important to identify locally grown acceptable foods that might be promoted to alleviate this problem. Pandanus fruit (Pandanus tectorius) is a well-liked indigenous Kiribati food with many cultivars that have orange/yellow flesh, indicative of carotenoid content. Few have been previously analysed.Aim: This study was conducted to identify cultivars of pandanus and other foods that could be promoted to alleviate VAD in Kiribati.Method: Ethnography was used to select foods and assess acceptability factors. Pandanus and other foods were analysed for beta- and alpha-carotene, beta-cryptoxanthin, lutein, zeaxanthin, lycopene and total carotenoids using high-performance liquid chromatography.Results: Of the nine pandanus cultivars investigated there was a great range of provitamin A carotenoid levels (from 62 to 19,086 microg beta-carotene/100 g), generally with higher levels in those more deeply coloured. Seven pandanus cultivars, one giant swamp taro (Cyrtosperma chamissonis) cultivar and native fig (Ficus tinctoria) had significant provitamin A carotenoid content, meeting all or half of estimated daily vitamin A requirements within normal consumption patterns. Analyses in different laboratories confirmed high carotenoid levels in pandanus but showed that there are still questions as to how high the levels might be, owing to variation arising from different handling/preparation/analytical techniques.Conclusions: These carotenoid-rich acceptable foods should be promoted for alleviating VAD in Kiribati and possibly other Pacific contexts where these foods are important. Further research in the Pacific is needed to identify additional indigenous foods with potential health benefits. [ABSTRACT FROM AUTHOR]

This review explores the challenges and potential solutions in plant micropropagation and biotechnology. While these techniques have proven successful for many species, certain plants or tissues are recalcitrant and do not respond as desired, limiting the application of these technologies due to unattainable or minimal in vitro regeneration rates. Indeed, traditional in vitro culture techniques may fail to induce organogenesis or somatic embryogenesis in some plants, leading to classification as in vitro recalcitrance. This paper focuses on recalcitrance to somatic embryogenesis due to its promise for regenerating juvenile propagules and applications in biotechnology. Specifically, this paper will focus on epigenetic factors that regulate recalcitrance as understanding them may help overcome these barriers. Transformation recalcitrance is also addressed, with strategies proposed to improve transformation frequency. The paper concludes with a review of CRISPR-mediated genome editing's potential in modifying somatic embryogenesis-related epigenetic status and strategies for addressing transformation recalcitrance., Competing Interests: The authors declare there are no competing interests.

In cannabis seedlings, the initiation of solitary flowers is photoperiod-independent. However, when cannabis reaches the adult stage, short-day photoperiod (SD) triggers branching of the shoot apex and a reduction in internode length, leading to development of a condensed inflorescence. We demonstrate that SD affects cannabis plants in two distinct phases: the first includes rapid elongation of the internodes and main stem, and occurring from Day 5 to Day 10 of plant cultivation under SD; in the second phase, elongation of newly developed internodes ceases, and a condensed inflorescence is formed. Exposure of plants to alternating photoperiods revealed that inflorescence onset requires at least three consecutive days of SD, and SD is consistently required throughout inflorescence maturation to support its typical condensed architecture. This photoperiod-dependent morphogenesis was associated with a decrease in gibberellin (GA 4 ) and auxin levels in the shoot apex. Reverting the plants to a long-day photoperiod (LD) increased GA 4 and auxin levels, leading to inflorescence disassembly, internode elongation, and subsequent resumption of LD growth patterns. Similar developmental patterns were observed under SD following the application of exogenous GA (and not auxin), which also impeded inflorescence development. Nevertheless, additional studies will help to further evaluate auxin's role in these developmental changes. We propose a crucial role for GA in sexual reproduction and inflorescence development in female cannabis by mediating photoperiod signaling in the inflorescence tissues., Competing Interests: The authors declare no conflicts of interest., (© The Author(s) 2024. Published by Oxford University Press on behalf of Nanjing Agricultural University.)

The epidermal cells of petunia (Petunia × hybrida) flowers are the main site of volatile emission. However, the mechanisms underlying the release of volatiles into the environment are still being explored. Here, using cell-layer-specific transcriptomic analysis, reverse genetics by virus-induced gene silencing and clustered regularly interspaced short palindromic repeat (CRISPR), and metabolomics, we identified EPIDERMIS VOLATILE EMISSION REGULATOR (EVER)-a petal adaxial epidermis-specific MYB activator that affects the emission of volatiles. To generate ever knockout lines, we developed a viral-based CRISPR/Cas9 system for efficient gene editing in plants. These knockout lines, together with transient-suppression assays, revealed EVER's involvement in the repression of low-vapor-pressure volatiles. Internal pools and annotated scent-related genes involved in volatile production and emission were not affected by EVER. RNA-Seq analyses of petals of ever knockout lines and EVER-overexpressing flowers revealed enrichment in wax-related biosynthesis genes. Liquid chromatography/gas chromatography-MS analyses of petal epicuticular waxes revealed substantial reductions in wax loads in ever petals, particularly of monomers of fatty acids and wax esters. These results implicate EVER in the emission of volatiles by fine-tuning the composition of petal epicuticular waxes. We reveal a petunia MYB regulator that interlinks epicuticular wax composition and volatile emission, thus unraveling a regulatory layer in the scent-emission machinery in petunia flowers., Competing Interests: Conflict of interest statement. None declared., (© American Society of Plant Biologists 2023. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

This paper presents a protocol for the convenient and high-throughput isolation and enrichment of glandular capitate stalked and sessile trichomes from Cannabis sativa. The biosynthetic pathways for cannabinoid and volatile terpene metabolism are localized primarily in the Cannabis trichomes, and isolated trichomes are beneficial for transcriptome analysis. The existing protocols for isolating glandular trichomes for transcriptomic characterization are inconvenient and deliver compromised trichome heads and a relatively low amount of isolated trichomes. Furthermore, they rely on expensive apparatus and isolation media containing protein inhibitors to avoid RNA degradation. The present protocol suggests combining three individual modifications to obtain a large amount of isolated glandular capitate stalked and sessile trichomes from C. sativa mature female inflorescences and fan leaves, respectively. The first modification involves substituting liquid nitrogen for the conventional isolation medium to facilitate the passage of trichomes through the micro-sieves. The second modification involves using dry ice to detach the trichomes from the plant source. The third modification involves passing the plant material consecutively through five micro-sieves of diminishing pore sizes. Microscopic imaging demonstrated the effectiveness of the isolation technique for both trichome types. In addition, the quality of RNA extracted from the isolated trichomes was appropriate for downstream transcriptomic analysis.

Key Message: Vegetative-to-reproductive phase transition in female cannabis seedlings occurs autonomously with the de novo development of single flowers. To ensure successful sexual reproduction, many plant species originating from seedlings undergo juvenile-to-adult transition. This phase transition precedes and enables the vegetative-to-reproductive shift in plants, upon perception of internal and/or external signals such as temperature, photoperiod, metabolite levels, and phytohormones. This study demonstrates that the juvenile seedlings of cannabis gradually shift to the adult vegetative stage, as confirmed by the formation of lobed leaves, and upregulation of the phase-transition genes. In the tested cultivar, the switch to the reproductive stage occurs with the development of a pair of single flowers in the 7th node. Histological analysis indicated that transition to the reproductive stage is accomplished by the de novo establishment of new flower meristems which are not present in a vegetative stage, or as dormant meristems at nodes 4 and 6. Moreover, there were dramatic changes in the transcriptomic profile of flowering-related genes among nodes 4, 6, and 7. Downregulation of flowering repressors and an intense increase in the transcription of phase transition-related genes occur in parallel with an increase in the transcription of flowering integrators and meristem identity genes. These results support and provide molecular evidence for previous findings that cannabis possesses an autonomous flowering mechanism and the transition to reproductive phase is controlled in this plant mainly by internal signals., (© 2022. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

The deep ocean is the largest ecosystem on the planet, constituting greater than 90% of all habitable space. Over three-quarters of countries globally have deep ocean within their Exclusive Economic Zones. While maintaining deep-ocean function is key to ensuring planetary health, deficiencies in knowledge and governance, as well as inequitable global capacity, challenge our ability to safeguard the resilience of this vast realm, leaving the fate of the deep ocean in the hands of a few. Historically, deep-ocean scientific exploration and research have been the purview of a limited number of nations, resulting in most of humankind not knowing the deep ocean within their national jurisdiction or beyond. In this article, we highlight the inequities and need for increased deep-ocean knowledge generation, and discuss experiences in piloting an innovative project 'My Deep Sea, My Backyard' toward this goal. Recognizing that many deep-ocean endeavours take place in countries without deep-ocean access, this project aimed to reduce dependency on external expertise and promote local efforts in two small island developing states, Trinidad and Tobago and Kiribati, to explore their deep-sea backyards using comparatively low-cost technology while building lasting in-country capacity. We share lessons learned so future efforts can bring us closer to achieving this goal. This article is part of the theme issue 'Nurturing resilient marine ecosystems'.

Medical cannabis ( Cannabis sativa L.) is quickly becoming a central agricultural crop as its production has continued to increase globally. The recent release of the cannabis reference genomes provides key genetic information for the functional analysis of cannabis genes. Currently, however, the established tools for in vivo gene functional analysis in cannabis are very limited. In this study, we investigated the use of the tobacco rattle virus (TRV) as a possible tool for virus-induced gene silencing (VIGS) and virus-aided gene expression (VAGE). Using leaf photobleaching as a visual marker of PHYTOENE DESATURASE ( PDS ) silencing, we found that VIGS was largely restricted to the agro-infiltrated leaves. However, when agro-infiltration was performed under vacuum, VIGS increased dramatically, which resulted in intense PDS silencing and an increased photobleaching phenotype. The suitability of TRV as a vector for virus-aided gene expression (VAGE) was demonstrated by an analysis of DsRed fluorescence protein. Interestingly, a DsRed signal was also observed in glandular trichomes in TRV 2 - DsRed -infected plants, which suggests the possibility of trichome-related gene function analysis. These results indicate that TRV, despite its limited spread, is an attractive vector for rapid reverse-genetics screens and for the analysis of gene function in cannabis.

Main Conclusion: Elevated temperatures suppress cell division in developing petunia buds leading to smaller flowers, mediated by ABA. Flower size is one of the most important showy traits in determining pollinator attraction, and a central factor determining the quality of floricultural products. Whereas the adverse effects of elevated temperatures on showy traits have been described in detail, its underlining mechanisms is poorly understood. Here, we investigated the physiological mechanism responsible for the reduction of flower size in petunia under elevated temperatures. We found that the early stages of flower-bud development were most sensitive to elevated temperatures, resulting in a drastic reduction of flower diameter that was almost independent of flower load. We demonstrated that the temperature-mediated flower size reduction occurred due to a shorter growth period, and a lower rate of corolla cell division. Consistently, local application of cytokinin, a phytohormone that promotes cell division, resulted in recovery of flower dimensions when grown under elevated temperatures. Hormone analysis of temperature-inhibited flower buds revealed no significant changes in levels of cytokinin, and a specific increase of abscisic acid (ABA) levels, known to inhibit cell division. Moreover, local application of ABA on flower buds caused a reduction of flower dimensions as a result of lower levels of cell division, suggesting that ABA mediates the reduction of flower size at elevated temperatures. Taken together, our results shed light on the mechanism by which elevated temperatures decrease petunia flower size, and show that temperature-mediated reduction of flower size can be alleviated by increasing the cytokinin/ABA ratio., (© 2021. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

MicroRNA172 (miR172) functions as a central regulator of flowering time and flower development by post-transcriptional repression of APETALA2-LIKE transcription factors. In the model crop Solanum lycopersicum (tomato), the miR172 family is still poorly annotated and information about the functions of specific members is lacking. Here, de-novo prediction of tomato miR172 coding loci identified seven genes ( SlMIR172a-g ), that code for four unique species of miR172 (sly-miR172). During reproductive development, sly-miR172s are differentially expressed, with sly-miR172c and sly-miR172d being the most abundant members in developing flowers, and are predicted to guide the cleavage of eight APETALA2-LIKE transcription factors. By CRISPR-Cas9 co-targeting of SlMIR172c and SlMIR172d we have generated a battery of loss-of-function and hypomorphic mutants ( slmir172c-d CR ). The slmir172c-d CR plants developed normal shoot but their flowers displayed graded floral organ abnormalities. Whereas slmir172c CR loss-of-function caused only a slight greening of petals and stamens, hypomorphic and loss-of-function slmir172d CR alleles were associated with the conversion of petals and stamens to sepaloids, which were produced in excess. Interestingly, the degrees of floral organ identity alteration and proliferation were directly correlated with the reduction in sly-miR172d activity. These results suggest that sly-miR172d regulates in a dose-dependent manner floral organ identity and number, likely by negatively regulating its APETALA2-like targets.

Flowers are the most vulnerable plant organ to infection by the necrotrophic fungus Botrytis cinerea. Here we show that pre-treatment of chrysanthemum (Chrysanthemum morifolium) flowers with phenylalanine (Phe) significantly reduces their susceptibility to B. cinerea. To comprehend how Phe treatment induces resistance, we monitored the dynamics of metabolites (by GC/LC-MS) and transcriptomes (by RNAseq) in flowers after Phe treatment and B. cinerea infection. Phe treatment resulted in accumulation of 3-phenyllactate and benzaldehyde, and in particular induced the expression of genes related to Ca 2+ signaling and receptor kinases, implicating an induction of the defense response. Interestingly, the main effects of Phe treatment were observed in flowers exposed to B. cinerea infection, stabilizing the global fluctuations in the levels of metabolites and transcripts while reducing susceptibility to the fungus. We suggest that Phe-induced resistance is associated to cell priming, enabling rapid and targeted reprogramming of cellular defense responses to resist disease development. After Phe pre-treatment, the levels of the anti-fungal volatiles phenylacetaldehyde and eugenol were maintained and the level of coniferin, a plausible monolignol precursor in cell wall lignification, was strongly increased. In addition, Phe pre-treatment reduced ROS generation, prevented ethylene emission, and caused changes in the expression of a minor number of genes related to cell wall biogenesis, encoding the RLK THESEUS1, or involved in Ca 2+ and hormonal signaling processes. Our findings point to Phe pre-treatment as a potential orchestrator of a broad-spectrum defense response which may not only provide an ecologically friendly pest control strategy but also offers a promising way of priming plants to induce defense responses against B. cinerea., (© 2020 Society for Experimental Biology and John Wiley & Sons Ltd.)

The inflorescence is the main product of medical cannabis. Hundreds of specialized metabolites with potential bioactivity are produced and accumulated in the glandular trichomes that are highly abundant mainly on female inflorescences. Understanding the morphophysiological and genetic mechanisms governing flower and inflorescence development is therefore of high scientific and practical importance. However, in-depth investigations of cannabis florogenesis are limited. Cannabis producers and researchers consider long photoperiod to be "non-inductive" or "vegetative," but under these growth conditions, the development of solitary flowers and bracts in shoot internodes clearly indicates that the plant cannot be defined as vegetative or non-inductive in the classical sense. Most probably, induction of solitary flowers is age-dependent and controlled by internal signals, but not by photoperiod. Short photoperiod induces intense branching, which results in the development of a compound raceme. Each inflorescence consists of condensed branchlets with the same phytomer structure as that of the larger phytomers developed under long day. Each phytomer consists of reduced leaves, bracts, one or two solitary flowers, and an axillary shoot (or inflorescence). Therefore, the effect of short photoperiod on cannabis florogenesis is not flower induction, but rather a dramatic change in shoot apex architecture to form a compound racemose inflorescence structure. An understanding of the morphophysiological characteristics of cannabis inflorescence will lay the foundation for biotechnological and physiological applications to modify architecture and to maximize plant productivity and uniformity in medical Cannabis .

Emission of volatiles at advanced stages of flower development is a strategy used by plants to lure pollinators to the flower. We reveal that GA negatively regulates floral scent production in petunia. We used Agrobacterium-mediated transient expression of GA-20ox in petunia flowers and a virus-induced gene silencing approach to knock down DELLA expression, measured volatile emission, internal pool sizes and GA levels by GC-MS or LC-MS/MS, and analyzed transcript levels of scent-related phenylpropanoid-pathway genes. We show that GA has a negative effect on the concentrations of accumulated and emitted phenylpropanoid volatiles in petunia flowers; this effect is exerted through transcriptional/post-transcriptional downregulation of regulatory and biosynthetic scent-related genes. Both overexpression of GA20-ox, a GA-biosynthesis gene, and suppression of DELLA, a repressor of GA-signal transduction, corroborated GA's negative regulation of floral scent. We present a model in which GA-dependent timing of the sequential activation of different branches of the phenylpropanoid pathway during flower development may represent a link between the showy traits controlling pollinator attraction, namely color and scent., (© 2017 The Authors. New Phytologist © 2017 New Phytologist Trust.)

The mechanism underlying the emission of phenylpropanoid volatiles is poorly understood. Here, we reveal the involvement of PH4, a petunia MYB-R2R3 transcription factor previously studied for its role in vacuolar acidification, in floral volatile emission. We used the virus-induced gene silencing (VIGS) approach to knock down PH4 expression in petunia, measured volatile emission and internal pool sizes by GC-MS, and analyzed transcript abundances of scent-related phenylpropanoid genes in flowers. Silencing of PH4 resulted in a marked decrease in floral phenylpropanoid volatile emission, with a concurrent increase in internal pool levels. Expression of scent-related phenylpropanoid genes was not affected. To identify putative scent-related targets of PH4, we silenced PH5, a tonoplast-localized H(+) -ATPase that maintains vacuolar pH homeostasis. Suppression of PH5 did not yield the reduced-emission phenotype, suggesting that PH4 does not operate in the context of floral scent through regulation of vacuolar pH. We conclude that PH4 is a key floral regulator that integrates volatile production and emission processes and interconnects two essential floral traits - color and scent., (© 2015 The Authors. New Phytologist © 2015 New Phytologist Trust.)

The Republic of Kiribati's Phoenix Islands Protected Area (PIPA), located in the equatorial central Pacific, is the largest and deepest UNESCO World Heritage site on earth. Created in 2008, it was the first Marine Protected Area (MPA) of its kind (at the time of inception, the largest in the world) and includes eight low-lying islands, shallow coral reefs, submerged shallow and deep seamounts and extensive open-ocean and ocean floor habitat. Due to their isolation, the shallow reef habitats have been protected de facto from severe exploitation, though the surrounding waters have been continually fished for large pelagics and whales over many decades. PIPA was created under a partnership between the Government of Kiribati and the international non-governmental organizations-Conservation International and the New England Aquarium. PIPA has a unique conservation strategy as the first marine MPA to use a conservation contract mechanism with a corresponding Conservation Trust established to be both a sustainable financing mechanism and a check-and-balance to the oversight and maintenance of the MPA. As PIPA moves forward with its management objectives, it is well positioned to be a global model for large MPA design and implementation in similar contexts. The islands and shallow reefs have already shown benefits from protection, though the pending full closure of PIPA (and assessments thereof) will be critical for determining success of the MPA as a refuge for open-ocean pelagic and deep-sea marine life. As global ocean resources are continually being extracted to support a growing global population, PIPA's closure is both timely and of global significance.

Flower scent is a composite character determined by a complex mixture of low-molecular-weight volatile molecules. Despite the importance of floral fragrance, our knowledge on factors regulating these pathways remains sketchy. Virus-induced gene silencing (VIGS) and virus-aided gene expression (VAGE) are characterized by a simple inoculation procedure and rapid results as compared to transgenesis, allowing screening and characterization of scent-related genes. Here, we describe methods using TRV as a VIGS/VAGE vector for the characterization of scent-related genes, protein compartmentalization studies, and protein subcellular targeting.

Flower scent is a highly dynamic trait, under developmental, spatial, and diurnal regulation. The mechanism governing scent production is only beginning to be unraveled. In petunia (Petunia hybrida), EMISSION OF BENZENOIDS II (EOBII) controls transcription of both the shikimate pathway-regulating MYB factor ODORANT1 (ODO1) and phenylpropanoid scent-related structural genes. A promoter-activation screen identified an R2R3-MYB-like regulatory factor of phenylpropanoid volatile biosynthesis acting downstream of EOBII, designated EOBI. EOBI silencing led to downregulation of ODO1 and numerous structural scent-related genes from both the shikimate and phenylpropanoid pathways. The ability of EOBI to directly activate ODO1, as revealed by electrophoretic mobility shift assay and yeast one-hybrid analysis, place EOBI upstream of ODO1 in regulating substrate availability for volatile biosynthesis. Interestingly, ODO1-silenced transgenic petunia flowers accumulated higher EOBI transcript levels than controls, suggesting a complex feedback loop between these regulatory factors. The accumulation pattern of EOBI transcript relative to EOBII and ODO1, and the effect of up/downregulation of EOBII on transcript levels of EOBI and ODO1, further support these factors' hierarchical relationships. The dependence of scent production on EOBI expression and its direct interaction with both regulatory and structural genes provide evidence for EOBI's wide-ranging involvement in the production of floral volatiles.

Floral scent, which is determined by a complex mixture of low molecular weight volatile molecules, plays a major role in the plant's life cycle. Phenylpropanoid volatiles are the main determinants of floral scent in petunia (Petunia hybrida). A screen using virus-induced gene silencing for regulators of scent production in petunia flowers yielded a novel R2R3-MYB-like regulatory factor of phenylpropanoid volatile biosynthesis, EMISSION OF BENZENOIDS II (EOBII). This factor was localized to the nucleus and its expression was found to be flower specific and temporally and spatially associated with scent production/emission. Suppression of EOBII expression led to significant reduction in the levels of volatiles accumulating in and emitted by flowers, such as benzaldehyde, phenylethyl alcohol, benzylbenzoate, and isoeugenol. Up/downregulation of EOBII affected transcript levels of several biosynthetic floral scent-related genes encoding enzymes from the phenylpropanoid pathway that are directly involved in the production of these volatiles and enzymes from the shikimate pathway that determine substrate availability. Due to its coordinated wide-ranging effect on the production of floral volatiles, and its lack of effect on anthocyanin production, a central regulatory role is proposed for EOBII in the biosynthesis of phenylpropanoid volatiles.

Neglect of traditional food systems has led to serious nutrition and health problems throughout the Pacific Islands. At the same time, there is concern about the loss of traditional knowledge, customs and culture related to local foods, and of biodiversity. However, there is still a great diversity of nutrient-rich local food crops in the Pacific, along with considerable knowledge about these foods, their methods of production, harvesting, storage, and preparation. An integrated approach is needed in order to make a meaningful impact on increased production, marketing/processing and use of local food crops and foods for better health and nutrition, requiring greater collaboration between the health sector and agencies in other sectors. Priorities for action include: documentation and assessment of traditional food systems, including analysis of local foods and crop varieties for their nutrient content; innovative means of increasing awareness of the values of local foods among the general public and policy makers; conservation of rare varieties of crops and food trees and protection of the environment; and an increased focus on small-scale processing and marketing of local foods. Overriding all of this is the urgent need to mainstream consideration of these important issues into relevant national and regional policies. The rubric "Biodiversity for Health and Nutrition" incorporates all of these issues and provides a framework within which all partner agencies can be involved.

Between August 1980 and October 1990 we treated 36 patients with home total parenteral nutrition (HTPN) with a cumulative treatment duration of 92 years. They included 14 females and 22 males ranging in age from newborn to 75 years, with a mean of 38 +/- 21. The 4 commonest indications for HTPN were short bowel syndrome (mainly due to mesenteric occlusion (50%), inflammatory bowel disease 14%), motility disorders (14%) and malabsorption (11%). All-in-one nutritional mixtures utilizing the big-bag technique were used for all patients. Broviac or Hickman catheters were implanted in 35 patients and an infusion port in 2. Infusions were administered during the night for 8-12 hours with a volumetric pump. 14 patients are still receiving HTPN (39%) while in 8 it was discontinued as they can maintain their nutritional status by the gastrointestinal route (22%). 14 patients have died (39%), 3 from HTPN-related causes (2 of sepsis and 1 of liver failure). Catheter-related sepsis was 0.42/year of HTPN. Other common complications were metabolic bone disease, deranged liver function and cholecystolithiasis. 80% were able to return to work, school, or housekeeping activities, or at least to take care of themselves and cope with HTPN unaided. Social rehabilitation was full or partial in 72% and only 29% were house-bound and needed major assistance. Patients with a poor life quality tended to be older and suffer from intestinal diseases as a manifestation of a systemic disorder, such as atherosclerosis or malignancy.(ABSTRACT TRUNCATED AT 250 WORDS)

Metabolic bone disease occurs in patients receiving prolonged home total parenteral nutrition (HTPN). We studied bone-mass status in 10 patients (seven males, three females, age 19-66 years) who had been receiving HTPN for 0 to 67 months (mean 24 months), mostly for short-bowel syndrome. Four patients had spinal osteoporosis on radiograms. The density of various bone components at the wrist was measured noninvasively using a novel technique based on Compton scattering effect. The density of the cancellous and cortical bone was decreased in nine and six patients, respectively. During a follow-up period of up to 19 months, a further significant decrease in the density of both bone components was found. We conclude that prolonged HTPN is associated with an ongoing bone diminution, affecting mainly the cancellous bone.