Intact Bodies Research Articles

Myxococcus xanthus fruiting body morphology is important for spore recovery after exposure to environmental stress.

Environmental microorganisms have evolved a variety of strategies to survive fluctuations in environmental conditions, including the production of biofilms and differentiation into spores. Myxococcus xanthus are ubiquitous soil bacteria that produce starvation-induced multicellular fruiting bodies filled with environmentally resistant spores (a specialized biofilm). Isolated spores have been shown to be more resistant than vegetative cells to heat, ultraviolet radiation, and desiccation. The evolutionary advantage of producing spores inside fruiting bodies is not clear. Here, we examine a hypothesis that the fruiting body provides additional protection from environmental insults. We developed a high-throughput method to compare the recovery (outgrowth) of distinct cell types (vegetative cells, free spores, and spores within intact fruiting bodies) after exposure to ultraviolet radiation or desiccation. Our data indicate that haystack-shaped fruiting bodies protect spores from extended UV radiation but do not provide additional protection from desiccation. Perturbation of fruiting body morphology strongly impedes recovery from both UV exposure and desiccation. These results hint that the distinctive fruiting bodies produced by different myxobacterial species may have evolved to optimize their persistence in distinct ecological niches.IMPORTANCEEnvironmental microorganisms play an important role in the production of greenhouse gases that contribute to changing climate conditions. It is imperative to understand how changing climate conditions feedback to influence environmental microbial communities. The myxobacteria are environmentally ubiquitous social bacteria that influence the local microbial community composition. Defining how these bacteria are affected by environmental insults is a necessary component of predicting climatic feedback effects. When starved, myxobacteria produce multicellular fruiting bodies filled with spores. As spores are resistant to a variety of environmental insults, the evolutionary advantage of building a fruiting body is not clear. Using the model myxobacterium, Myxococcus xanthus, we demonstrate that the tall, haystack-shaped fruiting body morphology enables significantly more resistance to UV exposure than the free spores. In contrast, fruiting bodies are slightly detrimental to recovery from extended desiccation, an effect that is strongly exaggerated if fruiting body morphology is perturbed. These results suggest that the variety of fruiting body morphologies observed in the myxobacteria may dictate their relative resistance to changing climate conditions.

Recovery of independent ambulation after complete spinal cord transection in the presence of the neuroprotectant polyethylene glycol in monkeys

ObjectiveDespite the conventional belief that motor function and sensation distal to the site of a complete spinal cord transection are irretrievable, our research has demonstrated significant motor recovery in mice, rats, and dogs by applying polyethylene glycol (PEG) topically via a syringe directly to the contact interface of transected spinal cord. However, before implementing this technology in human subjects, validating PEG's efficacy and enduring impact through experimentation on non-human primates is imperative. MethodsTwo 4-year-old female Macaca fascicularis monkeys underwent complete dorsal cord transection at T10. Postoperative behavioral assessment, electrophysiologic monitoring, and neuroimaging examinations were recorded, and tissues were obtained for histological examination at the end of study. ResultsThe monkey whose spinal cord had been fully transected in the presence of PEG developed useful recovery already at 3 months and near-complete recovery of motor function in the hind-limbs at 18 months. The control animal without PEG remained paralyzed. Cortical somatosensory evoked potentials recovered postoperatively only in PEG-treated monkey vs none in the control. Diffusion tensor imaging showed re-establishment of continuity of the white matter in PEG-treated monkey, but not in the control. Moreover, histology revealed intact neuronal bodies, axons, and myelin tissue at the spinal cord transection site in PEG-treated monkey only. ConclusionThis report suggests that in primates, an acutely transected spinal cord can be re-fused in the presence of PEG with restoration of neural continuity and functional recovery of motor activity distal to the site of transection.

Mechanism of analgesic effect of electroacupuncture on rats with cervical spondylosis radiculopathy based on activation of astrocytes and HMGB1/TLR4/MyD88 signaling pathway

To observe effects of electroacupuncture (EA) on the activation of astrocytes and high mobility group protein B1(HMGB1)/Toll-like receptor 4 (TLR4)/myeloid differentiation factor 88 (MyD88) signaling pathway, as well as related cytokines in rats with cervical spondylosis radiculopathy(CSR), so as to explore the analgesic mechanism of EA in treating CSR. Twenty-four male SD rats were randomly divided into blank, sham surgery, model, and EA groups, with 6 rats in each group. CSR rat model was established by using cervical spinal cord canal puncture method. On the 7th day after successful modeling, EA was applied to rats in the EA group at bilateral "Hegu"(LI4) and "Taichong"(LR3) for 20 minutes(1.5 Hz, 1 mA), once daily for 7 consecutive days. Before and after intervention, gait impairment scores and mechanical pain thresholds were assessed. HE staining was used to observe pathological changes in spinal cord tissue. Western blot was used to detect the expression of HMGB1, TLR4, MyD88, and glial fibrillary acidic protein (GFAP) in the spinal cord. ELISA was used to measure the contents of CXC chemokine ligand 1 (CXCL1), chemokine ligand 2 (CCL2), tumor necrosis factor (TNF)-α, and interleukin (IL)-1β in spinal cord. Immunofluorescence staining was used to observe GFAP protein positive expression in spinal cord tissue. There was no significant difference of all indexes between the blank group and the sham surgery group. Compared with the sham surgery group, mechanical pain threshold of rats in the model group was decreased(P<0.01), while gait impairment score, the contents of CXCL1, CCL2, TNF-α, IL-1β, protein expressions of HMGB1, TLR4, MyD88 and GFAP, and positive expression of GFAP in spinal cord tissue were increased (P<0.01)；HE staining indicated severe overall morphological damage in the spinal cord of rats in the model group, with significant shrinkage of gray matter neurons, reduced number of Nissl bodies, and increased inflammatory cell infiltration. Compared with the model group, mechanical pain threshold in the EA group was increased (P<0.01), while gait impairment score, the contents of CXCL1, CCL2, TNF-α, IL-1β, protein expressions of HMGB1, TLR4, MyD88 and GFAP, and positive expression of GFAP in spinal cord were reduced (P<0.01)；HE staining showed more intact neuronal cell bodies, increased number of Nissl bodies, and reduced shrinkage of gray matter neurons, inflammatory cell infiltration, and microvascular dilation in the spinal cord of rats in the EA group. EA can effectively alleviate pain in CSR rats, which is possibly by inhibiting astrocyte activation, HMGB1/TLR4/MyD88 signaling pathway, and reducing the release of related inflammatory cytokines, thus alleviating central sensitization in spinal segments.

Overexpression of the Capebp2 Gene Encoding the PEBP-like Protein Promotes the Cap Redifferentiation in Cyclocybe aegerita.

Phosphatidylethanolamine-binding protein (PEBP) is widely involved in various physiological behaviors, such as the transition from vegetative growth to reproductive growth in plants, tumorigenesis in the human, etc. However, few functional studies have examined pebp genes affecting the development of fungi. In this study, Capebp2 was cloned from Cyclocybe aegerita AC0007 strains based on the genome sequence and gene prediction, and the sequence alignment of CaPEBP2 with other PEBP proteins from other biological sources including plant, animal, fungi, and bacteria indicated that PEBP had low sequence similarity in fungi, whereas all protein sequences had some conserved motifs such as DPDAP and HRY. Expression analysis showed the transcription level of Capebp2 increased approximately 20-fold in fruiting bodies compared with mycelia. To uncover the function of Capebp2 in C. aegetita development, Capebp2 was cloned into a pATH vector driven by the actin promoter for obtaining overexpression transformant lines. Fruiting experiments showed the transformed strains overexpressing Capebp2 exhibited redifferentiation of the cap on their surface, including intact fruiting bodies or partial lamella during fruiting development stage, and the longitudinal section indicated that all regenerated bodies or lamella sprouted from the flesh and shared the epidermis with the mother fruiting bodies. In summary, the sequence characterization of Capebp2, expression level during different development stages, and function on fruiting body development were documented in this study, and these findings provided a reference to study the role of pebp in the development process of basidiomycetes. Importantly, gene mining of pebp, function characterization, and the regulating pathways involved need to be uncovered in further studies.

Extraction of structurally intact and well-stabilized rice bran oil bodies as natural pre-emulsified O/W emulsions and investigation of their rheological properties and components interaction

The isolated plant oil bodies (OBs) have shown promising applications as natural pre-emulsified O/W emulsions. Rice bran OBs can be used as a new type plant-based resource with superior fatty acids composition and abundant γ-oryzanol. This paper investigated the method of extracting structurally intact and stable rice bran OBs. Due to the adequate steric hindrance and electrostatic repulsion effects, rice bran OBs extracted by NaHCO3 medium had smaller particle size, better physical stability, and natural structure. The protein profile of NaHCO3-extracted rice bran OBs showed oleosin-L and oleosin-H, while exogenous proteins in PBS and enzyme-assisted- extracted rice bran OBs could interact with interfacial proteins through hydrophobic forces to aggregate adjacent OBs, further remodeling the OBs interface. It was also found that the small-sized rice bran OBs could adsorb on the interface of the larger-sized rice bran OBs like Pickering stabilizers. Rice bran OBs exhibited pseudoplastic fluids characteristic, but underwent a transition from solid-like to liquid-like behavior depending on the extraction method. The disorder of NaHCO3-extracted rice bran OBs protein molecules increased their surface hydrophobicity. The random coil structure favored more proteins adsorption at the interface of rice bran OBs extracted by PBS. Enzyme-assisted extraction of rice bran OBs had the highest content of β-sheet structure, which facilitated the stretching and aggregation of protein spatial structure. It was also confirmed the hydrogen bonding and hydrophobic interaction between the triacylglycerol or phospholipid and proteins molecules, and the membrane compositions of rice bran OBs differed between extraction methods.

Who Begins: Transfer and Transformation of Administrative Culture From the League of Nations to the World Health Organization

Abstract This article reconstructs the course of WHO-establishing activities and analyses how the WHO’s administrative culture was a continuation of its interwar predecessor, the League of Nations Health Organization, with the momentum of the war’s aftermath allowing for several overdue re-arrangements. Based on documentation of the WHO, the League of Nations Archive, as well as private records of key players, the article first traces strategic considerations by key players from only partially corresponding expert clusters, all entitled and aspiring to establish their version of the best public health agency possible. The establishing interactions between key experts and officials, but also personnel pooling logic and the early WHO’s approach to managing diversity of its staff speak for a considerable transfer of practices in administration between the predecessor and successor organizations. Despite the UN authorities’ programmatic statements, documents on the founding years of the WHO reveal an unbroken continuity of many intact administrative practices, functional bodies, and work focuses from the LNHO. These were largely defined by new labels and added to the legitimacy that the WHO needed in its formative years. Analyzing these continuities from the interwar decades of public health internationalism, the article spotlights the junctures where deliberate changes were undertaken disguised as the zero hour, allowing to resolve the previously unmanaged issues. The text thus contributes to a more complex and comprehensive picture of how international bodies of a global scale survive and live on, even after their presumed and declared death.

Spatial proteomics in three-dimensional intact specimens

Spatial molecular profiling of complex tissues is essential to investigate cellular function in physiological and pathological states. However, methods for molecular analysis of large biological specimens imagedin 3D arelacking. Here, we present DISCO-MS, a technology that combines whole-organ/whole-organism clearing and imaging, deep-learning-based image analysis, robotic tissue extraction, and ultra-high-sensitivity mass spectrometry. DISCO-MS yielded proteome data indistinguishable from uncleared samples in both rodent and human tissues. We used DISCO-MS to investigate microglia activation along axonal tracts after brain injury and characterized early- and late-stage individual amyloid-beta plaques in amouse model of Alzheimer's disease. DISCO-bot robotic sample extraction enabled us to study the regional heterogeneity of immune cells in intact mouse bodies and aortic plaques in a complete humanheart. DISCO-MS enables unbiased proteome analysis of preclinical and clinical tissues after unbiased imaging of entire specimens in 3D, identifying diagnostic and therapeutic opportunities for complex diseases. VIDEO ABSTRACT.

Exploiting encapsulated Himalayan walnut oil as a vivid source of essential fatty acids for the development of novel functional bread

SummaryThe basic aim of the study was to utilise Himalayan Walnut oil (HWO) encapsulated in soy protein isolate (SPI)–maltodextrin (MD)–pectin (Pec) complex as a potential source of omega fatty acids for bread fortification. Encapsulated HWO was integrated with bread for enhanced quality and technological aspects compared to control: it contained protein (9–19%), fat (6–8%), alpha‐linolenic acid (37.50%) with lower carbohydrate (35–42%) content. The baked loaves depicted higher specific loaf volume (3.85–4.85 cm3 g−1) with low hardness (4.24–5 N) due to the presence of hydrocolloids. Crust and crumb colour revealed a significant effect on the appearance of bread, with an increase in the antioxidant activity as assessed by 1,1‐diphenyl‐2‐picrylhydrazyl (80%), 2,2′‐Azino‐bis (3‐Ethylbenzothiazoline‐6‐Sulfonic Acid) (100%) and Metal Chelating Activity (10%). Compared to control, addition of encapsulated HWO increased final product quality by lowering oil oxidation during storage period. Scanning electron microscopic analysis showed intact encapsulated oil bodies in crumb after baking, thereby demonstrating high omega fatty acid retention.

Postharvest treatment of arginine maintains the storage quality of fresh‐cut button mushrooms ( Agaricus bisporus )

Fresh-sliced button mushrooms (Agaricus bisporus) are extremely perishable and deteriorate much faster than intact fruit bodies during storage. The aim of this study was to investigate the effects of different concentrations of arginine on the storage quality of fresh-sliced A. bisporus. All the arginine treatments showed the ability to maintain the quality of fresh-cut A. bisporus. The 0.4 mM arginine treatment most effectively maintained the sensory properties of fresh-cut button mushrooms because it delayed browning and weight loss, inhibited the increase in malondialdehyde content and polyphenol oxidase (PPO) activity, and promoted the activity of peroxidase and catalase, and increased the content of total phenolic and flavonoid substances. The 0.4 mM arginine treatment also significantly lowered the expression levels of three PPO genes on day 2. These results indicate that arginine treatment has a great potential to be applied for the quality retention of fresh-sliced mushrooms during storage. Practical applications This research reveals the ability of arginine as a preservative to prolong the storage life of mushroom slices. The completion of this research also provides a new and helpful insight into the preservation approach of fresh-cut products.

Monitoring of simulated clandestine graves of dismembered victims using UAVs, electrical tomography, and GPR over one year to aid investigations of human rights violations in Colombia, South America.

In most Latin American countries, there are significant numbers of missing people and forced disappearances, over 120,000 in Colombia alone. Successful detection of shallow buried human remains by forensic search teams is difficult in varying terrain and climates. Previous research has created controlled simulated clandestine graves of murder victims to optimize search techniques and methodologies. This paper reports on a study on controlled test site results over four simulated dismembered victims' clandestine graves as this is sadly a common scenario encountered in Latin America. Multispectral images were collected once post-burial, electrical resistivity surveys were collected 4 times, and ground penetrating radar (GPR) surveys were collected three times up to the end of the 371day survey monitoring period. After data processing, results showed that the multispectral data set could detect the simulated clandestine and control graves, with electrical resistivity imaging relative high resistances over some of the simulated graves but not over the empty control graves. GPR results showed good imaging on the Day 8surveys, medium imaging on the Day 294surveys, and medium to good imaging on the Day 371surveys. Study implications suggest that, while clandestine graves of dismembered homicide victims would likely result in smaller-sized graves when compared to graves containing intact bodies, these graves can still potentially be detected using remote sensing and geophysical methods.

Do sandwich vertebral bodies increase the risk of post-augmentation fractures? A retrospective cohort study.

Sandwich vertebral bodies (SVBs) are intact unaugmented vertebral bodies between two previously augmented vertebrae. Until recently, only a few studies have reported the outcomes and strategies for SVBs. This retrospective cohort study aimed to describe the clinical features and incidence of new fractures in patients with SVBs. The clinical data were collected from 179 patients with 237 symptomatic osteoporotic vertebral compression fractures who underwent vertebral augmentation (VA). Among them, 23 patients with 24 levels of SVBs were included. Spinal radiographs (X-ray and CT) of all patients were evaluated prior to surgery 1 day after primary VA and during follow-up. All patients successfully underwent PKP with an average follow-up period of 21.48 months. Asymptomatic cement leakage occurred in four patients (17.4%), and eight patients (34.8%) developed new fractures following primary PKP, including four sandwich, six adjacent, four remote vertebral fractures, and one re-collapse of cemented vertebrae. The incidence of new fractures in the SVB and control groups was 16.7% (4/24) and 13.0% (6/46), respectively, but there was no significant difference. Although patients with SVBs had a relatively high risk of developing new fractures after VA, the incidence rate of new fractures was not significantly different from that of the control group. However, the statistical power of this study was very limited. Therefore, and because the refracture rate in these patients is substantial, routine long-term monitoring of patients after VA for osteoporosis is strongly recommended.

Does tagging transparent fish increase predation risk? A laboratory study with glass eel (Anguilla anguilla) and sea bass (Dicentrarchus labrax).

Barriers in the estuaries of the rivers prevent the immigration of glass eels (Anguilla anguilla) arriving on the European coast every spring. This leads to an unnatural accumulation of migrating glass eels below the barriers, and this may lead to additional losses in glass eels by piscivorous fish. The proportion of predation losses can be estimated using mark‐recapture techniques and abundance estimates in combination with stomach content analysis of piscivorous fish. Nonetheless, whether tagging transparent glass eels increases predation risk and what the digestion rate of glass eel is in piscivorous fish are unknown. This study aimed to determine whether there is an increased predation risk for tagged glass eel; it also studies glass eel digestion status in piscivorous fish after appointed time frames. A laboratory experiment with 48 trials was conducted. Tagged (visible implanted elastomer, VIE) and untagged glass eels were exposed to small (19.1–24.4 cm) and large (31.9–43.5 cm) sea bass (Dicentrarchus labrax) during a 2 h trial. In 48% of the trials, successful predation was present and 13% showed clear predation attempts in which bass did not capture glass eels. No significant difference was found in predation rate between tagged and untagged glass eels and between red and blue tagged glass eels. Large sea bass predated more, but all sizes consumed glass eel under laboratory conditions. Stomach content analysis showed intact glass eel bodies 4–6 h after ending the 2 h trial and parts of glass eel bodies up to 16–18 h. This study showed that tagging does not increase predation in mark‐recapture studies using VIE‐tags in transparent glass eel. It also shows that the proportion of predation in relation to local glass eel abundance can be estimated if stomach content analysis is conducted within 4–6 h after predation.

A Jovian analogue orbiting a white dwarf star.

Studies1,2 have shown that the remnants of destroyed planets and debris-disk planetesimals can survive the volatile evolution of their host stars into white dwarfs3,4, but few intact planetary bodies around white dwarfs have been detected5-8. Simulations predict9-11 that planets in Jupiter-like orbits around stars of ≲8 M☉ (solar mass)avoid being destroyed by the strong tidal forces of their stellar host, but as yet, there has been no observational confirmation of such a survivor. Here we report the non-detection of a main-sequence lens star in the microlensing event MOA-2010-BLG-477Lb12 using near-infrared observations from the Keck Observatory. We determine that this system contains a 0.53 ± 0.11 M☉ white-dwarf host orbited by a 1.4±0.3 Jupiter-mass planet with a separation on the plane of the sky of 2.8 ± 0.5 astronomical units, which implies a semi-major axis larger than this. This system is evidence that planets around white dwarfs can survive the giant and asymptotic giant phases of their host's evolution, and supports the prediction that more than half of white dwarfs have Jovian planetary companions13. Located at approximately 2.0 kiloparsecs towards the centre of our Galaxy, it is likely torepresent an analogue to the end stages of the Sun and Jupiter in our own Solar System.

Toward a more sustainable mining future with electrokinetic in situ leaching.

Metals are currently almost exclusively extracted from their ore via physical excavation. This energy-intensive process dictates that metal mining remains among the foremost CO2 emitters and mine waste is the single largest waste form by mass. We propose a new approach, electrokinetic in situ leaching (EK-ISL), and demonstrate its applicability for a Cu-bearing sulfidic porphyry ore. In laboratory-scale experiments, Cu recovery was rapid (up to 57 weight % after 94 days) despite low ore hydraulic conductivity (permeability = 6.1 mD; porosity = 10.6%). Multiphysics numerical model simulations confirm the feasibility of EK-ISL at the field scale. This new approach to mining is therefore poised to spearhead a new paradigm of metal recovery from currently inaccessible ore bodies with a markedly reduced environmental footprint.

MEDI: Macronutrient Extraction and Determination from invertebrates, a rapid, cheap and streamlined protocol.

Macronutrients, comprising carbohydrates, proteins and lipids, underpin many ecological processes, but their quantification in ecological studies is often inaccurate and laborious, requiring large investments of time and bulk samples, which make individual‐level studies impossible. This study presents Macronutrient Extraction and Determination from Invertebrates (MEDI), a protocol for the direct, rapid and relatively low‐cost determination of macronutrient content from single small macroinvertebrates.Macronutrients were extracted by a sequential process of soaking in 1:12 chloroform:methanol solution to remove lipid and then solubilising tissue in 0.1 M NaOH. Proteins, carbohydrates and lipids were determined by colorimetric assays from the same individual specimens.The limits of detection of MEDI with the equipment and conditions used were 0.067, 0.065 and 0.006 mg/ml for proteins, carbohydrates and lipids respectively. Adjusting the volume of reagents used for extraction and determination can broaden the range of concentrations that can be detected. MEDI successfully identified taxonomic differences in macronutrient content between five insect species.Macronutrient Extraction and Determination from Invertebrates can directly and rapidly determine macronutrient content in tiny (dry mass ~3 mg) and much larger individual invertebrates. Using MEDI, the total macronutrient content of over 50 macroinvertebrates can be determined within around 3 days of collection at a cost of ~$1.35 per sample.

Human remains under the microscope of funerary taphonomy: Investigating the histological biography of the decaying body in the prehistoric Aegean

Funerary practices and especially the manipulation of the dead body have in the last decades become a central focus in prehistoric Aegean mortuary research. Variation in the character of human remains recovered from a rich array of mortuary contexts in varying state of articulation suggests that the dead were subject to a diverse range of mortuary rites. Taphonomic analysis of skeletal remains has been more recently employed by bioarchaeological research in the prehistoric Aegean with a view to understanding modes of pre- and post-burial treatment and reconstructing funerary activities. Recent studies of modern and archaeological bone have shown that bacterial bioerosion of internal bone microstructures is related to taphonomic processes which affect soft tissue decomposition and thus varies in ways which correspond to early post mortem funerary and corpse treatment. This paper presents the histotaphonomic analysis by thin section light microscopy of 108 human bones (107 individuals) from eleven Aegean human skeletal assemblages dating from the Neolithic to the Late Bronze Age. The results show variation in bacterial attack in different burial environments and often in the same deposit, which is more likely to reflect early taphonomic processes rather local soil circumstances. The microscopic analysis is combined with macroscopic (taphonomic surface modifications) and contextual information to discriminate between different formation mechanisms of skeletal assemblages and make inferences about funerary treatment and manipulation of the deceased. High levels of bacterial attack in Neolithic articulated and disarticulated samples suggest primary soil burial soon after death. Minoan bone assemblages provide evidence of considerable variation in levels of diagenesis, suggesting divergent taphonomic histories, whereas the results from Mycenaean sites are consistent with the deposition of fresh, intact bodies in chamber tombs, resulting in rapid skeletonisation by invertebrates and limited bone exposure to bacteria associated with soft tissue decomposition.

Determination of Adenosine and Cordycepin Concentrations in Cordyceps militaris Fruiting Bodies Using Near-Infrared Spectroscopy.

Near-infrared (NIRS) spectroscopy, coupled with partial least squares regression, was used to predict adenosine and cordycepin concentrations in fruiting bodies of Cordyceps militaris. The fruiting body samples were prepared in four different sample formats, which were intact fruiting bodies, chopped fruiting bodies, dried powder, and dried crude extract. The actual amount of the adenosine and cordycepin concentrations in fresh fruiting bodies was analyzed by high-performance liquid chromatography. Results showed that the prediction models developed from the chopped samples provided excellent accuracy in both parameters with minimal sample preparation. These optimum models provided a coefficient of determination of prediction, standard error of prediction, bias, and residual predictive deviation, which were respectively 0.95, 16.60 mg kg–1, –8.57 mg kg–1, and 5.04 for adenosine prediction, and 0.98, 181.56 mg kg–1, –1.05 mg kg–1, and 8.9 for cordycepin prediction. The accuracy and performance of the model were determined by ISO12099:2017(E). It was found that these two equations can be considered to be acceptable at a probability level of 95% confidence. The NIRS technique, therefore, has the potential to be an objective method for determining the adenosine and cordycepin concentrations in C. militaris fruiting bodies.

Recombinant Human Bone Morphogenetic Protein–2 Improves Spine Fusion in a Vitamin D–Deficient Rat Model

The effects of vitamin D deficiency on spinal fusion are not well studied, nor are approaches to overcoming deficiency-related detrimental effects. The purpose of this study was to (1) evaluate the effects of vitamin D deficiency on spine fusion in a rat model, and (2) determine whether recombinant human bone morphogenetic protein-2 (rhBMP-2) can improve outcomes in deficient rats. Sprague-Dawley rats were assigned to a vitamin D group: vitamin D sufficient (14), vitamin D deficient (16), vitamin D postoperative rescue (15). Posterolateral fusion was performed at L3-4 and L5-6, with one level receiving rhBMP-2 and the other allograft. Following 6 weeks, the spines were harvested for micro-computed tomography (micro-CT) and histological analyses. Fusion was assessed via manual palpation and micro-CT assessment. Micro-CT images were analyzed for bone microarchitecture in intact L5 vertebral bodies and within fused bone masses treated with rhBMP-2. There were no significant effects of vitamin D status on fusion assessments. However, the microarchitecture of native bone in the intact L5 vertebral bodies of vitamin D-sufficient rats showed significantly greater trabecular thickness (P < .001) and bone volume fraction (P < .001), with decreased trabecular spacing (P < .001), than that of vitamin D-deficient rats. Fusion masses of rhBMP-2 levels also showed significant effects of vitamin D supplementation on both bone volume fraction and trabecular thickness. Histological analysis confirmed that robust bone formation was observed in rhBMP-2-treated fusions, but not in fusion levels treated with allograft. Overall, vitamin D deficiency decreased trabecular bone microarchitecture, and treatment with rhBMP-2 improved outcomes across all vitamin D groups. Given the prevalence of vitamin D deficiency in spine surgery patients, vitamin D supplementation may be a cost-effective method for reducing the risk of pseudoarthrosis.

Spatial molecular-dynamically ordered NMR spectroscopy of intact bodies and heterogeneous systems

Noninvasive evaluation of the spatial distribution of chemical composition and diffusion behavior of materials is becoming possible by advanced nuclear magnetic resonance (NMR) pulse sequence editing. However, there is room for improvement in the spectral resolution and analytical method for application to heterogeneous samples. Here, we develop applications for comprehensively evaluating compounds and their dynamics in intact bodies and heterogeneous systems from NMR data, including spatial z-position, chemical shift, and diffusion or relaxation. This experiment is collectively named spatial molecular-dynamically ordered spectroscopy (SMOOSY). Pseudo-three-dimensional (3D) SMOOSY spectra of an intact shrimp and two heterogeneous systems are recorded to evaluate this methodology. Information about dynamics is mapped onto two-dimensional (2D) chemical shift imaging spectra using a pseudo-spectral imaging method with a processing tool named SMOOSY processor. Pseudo-2D SMOOSY spectral images can non-invasively assess the different dynamics of the compounds at each spatial z-position of the shrimp’s body and two heterogeneous systems.

The carotid bodies exercise control over active expiration but not peak performance during high-intensity treadmill running.

The carotid bodies exercise control over active expiration but not peak performance during high-intensity treadmill running.