Determining the optimal treatment course for a dermatologic burn wound requires knowledge of the wound’s severity, as quantified by the depth of thermal damage. In current clinical practice, burn depth is inferred based exclusively on superficial visual assessment, a method which is subject to substantial error rates in the classification of partial thickness (second degree) burns. Here, we present methods for direct, quantitative determination of the depth extent of injury to the dermal collagen matrix using polarization-sensitive optical coherence tomography (PS-OCT). By visualizing the depth-dependence of the degree of polarization of light in the tissue, rather than cumulative retardation, we enable direct and volumetric assessment of local collagen status. We further augment our PS-OCT measurements by visualizing adnexal structures such as hair follicles to relay overall dermal viability in the wounded region. Our methods, which we have validated ex vivo with matched histology, offer an information-rich tool for precise interrogation of burn wound severity and healing potential in both research and clinical settings. Although the severity of burn wounds is defined by how deeply the tissue is affected, burns are generally clinically assessed only at their surfaces by eye or camera. Among expert clinicians, this approach is effective in identifying mild, first-degree burns limited to the epidermis (the uppermost layer of the skin), as well as severe third-degree burns that extend through the dermis (the second layer of skin) to underlying subcutaneous fat or bone. However, even expert burn wound clinicians face an inaccuracy rate of 25-40% when evaluating second-degree, or partial thickness, burns, which encompass a wide range of injuries with some penetration into the dermis2. This presents a clinical challenge in proper management of burn wounds: shallower partial-thickness burns are expected to behave more similarly to first-degree burns and require minimal intervention, whereas deeper partial-thickness burns, analogously to third-degree burns, may require grafting for proper healing3. Partial-thickness burn wounds would also benefit from longitudinal monitoring; improperly treated burns may deepen over time, whereas properly managed burns see the healthy (re-)generation of scar and dermal tissue4. Therefore, there is strong clinical motivation for a non-invasive tool for longitudinal monitoring of burn wound injury depth to inform optimal treatment for patients.There is a need for tools to accurately evaluate the absolute depth extent of burn injuries in skin. Dermatological burns are a common injury, accounting for nearly 500,000 annual emergency department visits in the United States5. Not only does tissue biopsy lead to additional scarring and potential disruption of the healing process, but burn severity can vary greatly over even a very small area of tissue, complicating prediction of clinical outcome. Histological evaluation of burn wounds that extend into the dermis reveals the denaturation of dermal collagen, giving hematoxylin and eosin (H&E)-stained collagen fibers a glassy or “gelatinized” appearance6. Given the lack of tools for comprehensive collagen evaluation, it remains a challenge to understand how collagen damage directly relates to patient outcomes. Therefore, a key supplementary evaluation is identification of adnexal structures, such as hair follicles, which harbor stem cell reservoirs and drive dermatological healing7. Beyond evaluation of burn severity as first, second, or third degree, the presence of damaged or intact follicles at a given site informs healing potential, yielding valuable clinical prognostic information. However, with current gold-standard methods, the evaluation of these structures is limited to their incidence in histological cross-sections, which only sparsely sample the tissue compared to the full burn volume.The gold standard for quantitatively evaluating burn wound severity is punch biopsy followed by histological evaluation8. In thermally-damaged, gelatinized regions, collagen fibers denature and fuse, greatly reducing birefringence and polarization transformation9. An optical imaging modality which ideally capitalizes on this mechanism for volumetric burn detection is polarization-sensitive optical coherence tomography (PS-OCT), a functional extension of OCT10, which cross-sectionally images scattering media, including tissues in vivo and ex vivo, based on intrinsic contrast12. PS-OCT adds sensitivity to birefringent structures, such as healthy collagen fibers13. The volumetric, label-free imaging capabilities of OCT have further advantages over other optical methods, which may fundamentally lack depth-resolved information14, require tissue contact15, or have insufficent depth penetration to probe the full dermis16. In contrast, PS-OCT is capable of non-contact, depth-resolved imaging of tissue to depths up to 2 mm17.To more comprehensively characterize full burn volumes, various imaging approaches have been explored for burn wound assessment. Conventional medical imaging modalities such as MRI and ultrasound lack sufficient resolution to finely distinguish burn injury depths on the relevant scale ( tens of microns). As an alternative, optical imaging technologies offer higher resolution and a unique opportunity to probe the integrity of the dermal collagen matrix based on the interaction between this layer and the polarization of light. In healthy skin, the dense collagen matrix of the dermis exhibits high birefringence: collagen’s fibrillar structure strongly modulates the polarization state of incident light21. However, much of this work was limited to measuring cumulative retardation. While OCT is inherently a depth-resolved imaging technique, this metric only relates polarization-based information that is representative of a round trip path of light into and out of the tissue, rather than true characterization of local tissue properties. More recent progress in PS-OCT has enabled the measurement of local retardation  throughout tissue volumes, as well as the degree of polarization (DOP) at each imaged location22. DOP is an additional metric accessible via PS-OCT that has been shown to quantify the uniformity of the polarization states, impacted by the underlying tissue birefringence. Longitudinal assessment of DOP has been previously performed to distinguish mature from newly deposited collagen in the context of dermatologic wound healing24. In this work, we leverage the information yielded by DOP to assess the absolute depth extent of collagen damage as a function of burn wound severity in samples of porcine skin ex vivo, which is a closer structural and immunological match to human skin than that of other commonly used animal models such as rodents, though still suffers from functional limitations such as regenerative capacity25. DOP is an advantageous parameter for evaluation because it is measurable using simpler PS-OCT hardware and post-processing algorithms than are required to measure local retardation, bolstering its potential for rapid clinical adoption. Supported by rigorous histological evaluation, we find that DOP is a strong predictor of collagen status in tissues ex vivo, corresponding to burns from superficial to deep partial thickness. We further combine this polarimetric information relating dermal collagen integrity with the visualization of hair follicles to map adnexal structure location, jointly probing thermal injury depth and local tissue regeneration potential. Although thorough correlation between collagen damage and clinical burn outcomes remains yet unresolved, we hope that together, these data will provide a fuller clinical picture of damage and healing potential than existing imaging technologies at a far higher sampling rate than gold-standard punch biopsy methods. Further, our non-invasive, label-free technique potentiates accurate longitudinal evaluation of burn wound severity in vivo to assess the progression of healing over time. We envision this platform will offer value not only in the clinic, but also in research settings, for the evaluation of novel therapies for burn wound treatment and a thorough investigation of the relationship between collagen damage and dermal regenerative capacity that will enhance the translational value of this work.Prior work has specifically evaluated the efficacy of PS-OCT in determining burn wound severity en face throughout each volume [Fig. en face maps yielded little structural information with clear relevance to thermal damage, higher DOP was observed at increasingly greater depths into tissue with increasing burn duration. This confirmed our expectation that in healthy (unburned) skin, DOP decreases quickly with depth upon reaching the dense matrix of randomly-oriented collagen fibers of the dermis, whereas with loss of birefringent collagen following thermal injury, the polarization properties of incident light are unaltered in superficial burn regions. The resulting DOP remained high until interaction with the healthy, intact collagen matrix below, creating a clear injury border.To evaluate DOP as a predictor of dermal collagen damage depth extent and a surrogate measurement of burn wound severity, we induced burns with a continuously heated metal block at a range of durations, corresponding to differing severities, in samples of excised porcine skin Fig. a. Porcinentclass1pt{minimaentclass1pt{minimaentclass1pt{minima6.Following imaging, tissue was fixed in 10% formalin and paraffin embedded. Standard histologic sections were processed with hematoxylin and eosin (H&E) staining Fig. a,c,e,g. Representative cross sections showing OCT intensity Fig. a, tissueset Fig. f. Using 26. In general, deep, mature follicles give rise to hair shafts that extend up to the tissue surface. Cross-sections of hair follicles and hair shafts may appear more circular or oblique in geometry depending on their angle with respect to the plane of OCT imaging or histological embedding. With OCT imaging, the close analysis of such cross-sections shows the evolution of these structures with depth throughout a volume. Using a customized image processing routine, follicles were automatically identified throughout an OCT volume featuring regions of moderate and deep burn injury, as well as unburnt tissue [Fig. 27. This suggests that follicles in zones of significant collagen damage are also damaged themselves, an observation supported in existing literature28, making them unlikely to effectively contribute to the wound healing process through stem cell-based tissue regeneration. We envision that such en face healing potential maps will provide additional insight into both the location and the status of these regenerative structures. Importantly, these maps of healing potential offer more clinical context and prediction of patient outcomes than collagen injury mapping alone.Throughout histological cross sections Fig. a as wellsue Fig. b–d. The sue Fig. e. Additisue Fig. f to gene5, prioritizing the development of precise yet noninvasive methods. Our approach is straightforward and realizable with commercial OCT systems with polarization-diverse detection; since DOP measurements only require systems with a single input polarization state of light, they are simpler to acquire and to calculate than more advanced PS-OCT-based information. However, these advanced metrics, including local retardation22 and optic axis29, could also be highly informative for longitudinal wound-healing studies and a more thorough assessment of collagen reorganization. We also envision our approach will potentially be useful in validating even simpler OCT-based measurements such as tissue attenuation coefficient30, a non-polarization-based metric for tissue characterization which could eliminate the need for polarization-diverse detection hardware.PS-OCT measurements of DOP in skin show great promise for absolute determination of injury depth in burn wounds based on thermal damage to collagen. Volumetric, longitudinal mapping of collagen matrix integrity would not only fulfill an unmet clinical need where no tools currently exist, but would also provide a valuable tool to researchers investigating new therapies for debridement and accelerated wound healing strategies in animal models of burn injuries. While evaluating novel wound healing therapies, taking punch biopsies can add additional inflammation and alter the tissue microenvironment26, there remain differences in anatomy and healing properties, making it an imperfect surrogate sample. Further, under our experimental conditions, the ex vivo tissue lacked any perfusion. We expect that the burn times and temperatures used in this study would produce different severities if replicated in vivo, with heat dissipation via blood flow greatly reducing overall severity. However, in the scope of this work, an ex vivo environment provided an optimal environment for highly controllable burn induction. Since the goal of our preliminary study was only to evaluate the ability of DOP maps to quantitatively determine the depth extent of thermal damage to collagen in burned samples, using samples with regions of uniform burn depth, unimpacted by potentially differing levels of perfusion, produced results that were easy to interpret and average across samples and experiments for robust evaluation. Although the severity and uniformity of burn wounds would differ in vivo, we nonetheless expect DOP to remain as strong of a metric in revealing underlying burn wound structure, making our results relevant regardless of the tissue perfusion status. Future work will focus on addressing each of these limitations with experiments in human skin in vivo. Blood flow in tissue also presents an interesting additional form of contrast to be explored by OCT angiography30 to provide assessment of local perfusion in injured areas and potentially augment PS-OCT measurements. One environmental parameter not fully explored in this work was how the temperature of the block used to induce the burn wound may impact polarimetric results. While it is possible that the optical properties of the burned tissue may differ depending on temperature of burn induction, such as an increased optical attenuation coefficient in charred tissue, we predict that the polarimetric properties of the burned tissue, namely the strong decrease in DOP, will continue to produce strong contrast. We have verified over a small additional temperature range (110 °C to 170 °C) that we are still able to achieve accurate histological results  in terms of some aspects of its architecture and immunological behavior31 and circular ranging32, which promise to enable substantially larger-scale PS-OCT imaging in the future. Another potential limitation of OCT is its penetration depth; while  1-1.5mm is enough to assess the dermis at many anatomical locations, OCT sources at longer wavelengths (1.7 micron) could provide even deeper characterization of skin33.A fundamental limitation of OCT usage for many dermatological clinical applications is limited scan area. While OCT is still able to image far larger volumes than conventional microscopy techniques in far shorter time periods, many burn patients have injuries that cover a substantial proportion of total body surface area, rendering typical OCT fields of view (on the order of a few cubic centimeters) inadequate for full patient assessment in a reasonable amount of time. Nonetheless, our PS-OCT-based methods might be effectively combined with faster and higher-throughput tools such as visual assessment and digital photography, where areas of unclear severity could be spot-checked with a hand-held OCT probe. In the long run, the speed and range of OCT imaging continue to increase with fundamental advances such as ultrafast laser sources34. Since DOP measurements are sensitive to additive noise in each polarization channel, this SNR correction helped produce a DOP signal that diminished less with depth than the uncorrected signal  staining or left unstained. Four cross sections  were taken at regular intervals from each 0.5 cmA 100 22. Briefly, the system used a wavelength-swept laser centered at 1290 nm with a bandwidth of 115 nm, an A-line rate of 100 kHz, and an axial resolution of 9.4 The PS-OCT system used to acquire data in these experiments is described in detail elsewhereQ, U, V) and intensity (I) from the complex tomogram, the DOP, represented here by p denotes the input polarization state, and 34  and an estimated group refractive index for the dermis, composed primarily of water and collagen, of 1.4142. While it is possible that the tissue refractive index changed as a result of collagen denaturation and dermal dehydration, it is unlikely that this change would be of sufficient magnitude to substantially impact our results. Regions of interest (ROIs) spanning a representative sector of each burned volume, corresponding to a surface area of at least 3 mm An automated image processing pipeline used SNR-corrected DOP maps generated using PS-OCT processing to estimate burn wound injury depth. First, the surface of the tomogram was detected automatically. With a DOP threshold set to 0.95, the boundary beneath the surface at which the DOP fell below this value was identified, corresponding to healthy dermis and the return of a birefringent collagen signal. In unburned areas, this analysis resulted in non-zero burn depth estimates due to the lack of birefringence (and resulting high DOP) throughout the epidermis. The apparent depth extent of the collagen injury was determined with respect to the sample surface and mapped volumetrically Polarized light microscopy (PLM) imaging of unstained tissue sections was used as a ground truth method to determine the depth-extent of collagen injury in burned tissue samples. For each cross-sectional PLM image, the mean background signal was acquired and used to correct for any variation in light intensity within or across samples. The tissue surface was automatically extracted, as was the depth below the surface at which a sufficient birefringence signal was detected, corresponding to the presence of a healthy dermal collagen matrix. The mean injury depth was calculated from these two curves, then further averaged across the six cross sections for each burn duration obtained for each Dataset. Standard deviation was determined across these six independent measurements for each Dataset.The gelatinization zone in corresponding H&E-stained cross sections was used as an additional metric of collagen injury depth extent. In high-resolution digital pathology images, analogous image processing methods were used to detect the tissue surface and the boundary of the gelatinization zone based on Red-Green-Blue (RGB) thresholding, using threshold values optimized to match corresponding PLM results. As with the PLM results, the mean injury depth was calculated for each of the en face hair follicle maps were further smoothed with bwareaopen to highlight adjacent frames showing follicles evolving in depth.From OCT intensity data, a basic thresholding and image processing scheme was used to identify adnexal structures (e.g. hair follicles) as small, elliptically-shaped areas of relatively low intensity signal. A 2-D Wiener filter was applied to each cross-sectional image within the volume, and the tissue surface was identified, as was the point below the surface at which the intensity reached the noise floor. Tomograms were depth-compensated for attenuation, and resulting logarithmic intensity cross sections were thresholded to a value 5 dB above the noise floor. Identified low-signal areas were selected using built-in MATLAB function based on their shape  and size (bwareaopen). Identified regions with area above an empirically-determined maximum value were ignored as shadows of superficial hair shafts. Remaining areas were classified as hair follicles Fig. b; en facSupplementary Information.


Blood purification by hemoadsorption therapy seems to improve outcomes in selected patients undergoing cardiac surgery with cardiopulmonary bypass. Here, we report the successful application of hemoadsorption in the severe systemic inflammatory response during coronary artery bypass surgery in a patient with reactivated herpes zoster. The application of hemoadsorption therapy in cardiac surgery is increasing, as data have shown clinical benefits during complex procedures with a high risk for systemic inflammatory response or sepsis . This is™  on the CPB circuit. A 56-year-old man presented with unstable angina pectoris and stenosis of the left main. The patient’s history included arterial hypertension and severe chronic obstructive pulmonary and peripheral artery disease. Coronary angiography revealed severe three-vessel disease with high-grade stenoses of the left main, the proximal left, the anterior descending, the ramus intermedius coronary artery and an occluded right coronary artery. Transthoracic echocardiography showed a good left ventricular function without any sign of valvular dysfunction. Preoperative workup revealed proximal stenosis of the left subclavian artery with subclavian steal syndrome. During physical examination at admission, well-defined grouped vesicles could be identified on an erythematous background in a segmental nerve distribution of the left thorax Th2-3, . After dRemoval of cytokines by hemoadsorption in patients with sepsis or systemic inflammatory response syndrome has recently gained increased interest in cardiac surgery . However™ on VV-ECMO; however, it is difficult to draw any conclusions from this severely underpowered (17 patients per group) trial [The CytoSorb™ device has also been used as an adjunct therapy in critically ill COVID-19 patients with ARDS. Several published reports, including the multicenter U.S. CTC registry NCT04391920) have reported favorable outcomes and high survival rates in high-risk COVID-19 patients being treated with simultaneous hemoadsoprtion during veno-venous ECMO [91920 havOne limitation deserving mention is that only IL-6, PCT, and CRP were measured as markers of the severe inflammatory response in the present case, whereas numerous other markers may also be informative in this setting . Nevertheless, the presence of a cytokine storm is substantiated due to the fact that IL-6 levels in this case far exceeded the 15pg/mL upper reference limit of our laboratory.More evidence is needed to better define the value of hemoadsorption in cardiac surgery especially relating to appropriate patient selection and timing and dosing of application ,5. In 20This case suggests that hemoadsorption may be a vital adjunct therapeutic option for the management of a profound systemic inflammatory response in a patient requiring urgent cardiac surgery. From a clinician standpoint, the pros and cons for hemoadsorption are the following: Pros: (1) easy to implement in various extracorporeal circuits, (2) proven safety, and (3) potential preventive effect in cardiac surgery if implemented directly into CPB. Cons: (1) more data needed , (2) additional costs, and (3) the potential removal of antibiotics or beneficial substances. Therefore, future evaluations are needed for a better and more profound understanding of hemoadsorption. Recently, a dedicated risk score (CytoScore) has been proposed to help select the right patients and determine the right time for hemoadsorption initiation that may prove very useful if validated in future studies . Moreove


Excavations at Saruq al-Hadid, Dubai, UAE, discovered a stone tool technology with backed microliths dating to the Wadi Suq period and Late Bronze Age (ca. 1750–1300 BCE). The stone technology is a contemporary with metal production in the region, and the assemblage was recovered from a thick bone midden deposit at this multi-period site on the edge of the Rub’ al-Khali Desert. Small cobbles of chert were imported to the site and were reduced into flakes by hard-hammer percussion. Cores were frequently rotated during knapping and the reduction strategy was ad hoc, lacking hierarchical reduction stages. Flake tools were used as-is or modified by retouching. Some flakes were selected for backing into geometric microliths, and backing techniques often reflected high levels of stoneworking skill to produce stylised scalene shapes. A review of contemporary archaeological evidence, and the context of the Saruq al-Hadid assemblage, suggest that microliths may have been made as stone armatures for arrows despite the contemporary use of copper-based arrowheads. Saruq al-Hadid is a significant archaeological site located on the edge of the Rub’ al-Khali desert in Dubai, United Arab Emirates . The sitRecent excavations at Saruq al-Hadid recovered ca. 9100 stone artefacts, including backed microliths, from an extensive and dense midden deposit of animal bone which spans the Wadi Suq period and Late Bronze Age, c. 1750–1300 BC . Here weDuring this period at Saruq al-Hadid, stone tools were made and used alongside metal artefacts. The co-occurrence of stone and metal tools in the second millennium BCE is an important example of the continuity of stone technology after the development of metallurgy, a significant topic for lithic analysts –9 . Th5. Th3] dThe stone artefact assemblage was recovered from a dense bone midden, labelled Horizon IV , which wAlthough dominated by the material residues of wild animal hunting, the bone midden at Saruq al-Hadid likely reflects a strategy of logistical mobility incorporating hunting and herd management, undertaken by members of a spatially dispersed, multi-sited community also engaged in agro-pastoral subsistence practices at sites outside the desert zone . These aAll research work was undertaken under the auspices of contract 639/1/1413904 between the Dubai Municipality and the University of New England, Australia. All necessary permits were obtained for the described study, which complied with all relevant regulations. The Human Ethics Research Committee, University of New England, reviewed the project and confirmed in writing that ethics approval was not required.chaîne opératoire. The inferences underpinning a reduction sequence are qualitative but have material consequences that can be explored through metrical analysis and tested through experiments. The approach and terminology in this analysis follows Moore ); this variable is also relatively unstandardized . Flakes Flakes were recovered that are larger than the scars on discarded cores , in keepFreehand core reduction was sometimes done using anvil support, with blows oriented oblique to the core mass, as described above. A different anvil-support technique involved striking straight-in to the core mass. When the blow was applied near the centre of the blank’s surface, the object was broken in half or into sections of irregular shape. This variant of the technique is indicated by the presence of a demicone visible on the fractured edge of some artefacts.‘Truncated pieces’ are the sections with negative truncation scar attributes, and ‘truncation segments’ are the sections with positive truncation scar attributes , such as a positive demicone. If the blow was delivered close to the edge, the crack would initiate down the blank’s face, creating ‘planar backing flakes’. ‘Perverse backing flakes’ resulted from a spiral fracture mechanically identical to a perverse fracture in biface manufacture after , 61: ratStrong blows were delivered in truncating relatively thick blanks to ensure that the force was sufficient to ensure flake propagation through to the anvil support. Ventral attributes on the truncation byproducts tend to be distorted, with prominent compression ripples, and platforms are sometimes sheared or shattered. One flake truncated in this way was partially reconstructed through conjoining . Anvil sTruncation and microlith backing are ends of a technical continuum of flaking using anvil support, and the truncating/backing byproducts overlap morphologically. These byproducts tend to be wider than long  because The truncating/backing process was one of shaping a retouched edge by attrition, much like slicing a loaf of bread, and in the same way that the length of a bread slice indicates the height of the bread loaf, the length of a truncation/backing flake roughly indicates the thickness of the blank (within a margin of variation due to varying thickness across the flake blank). Therefore the thickness of truncation pieces and backed microliths reflects the thicknesses of blanks selected for backing. A comparison of these values suggests that small, thin flakes—less than 10 mm thick, and mostly less than 5 mm thick—were selected for manufacture through backing into microliths, whereas thicker blanks—but usually less than 25 mm thick—were truncated . The larThe previous discussion demonstrates that the core reduction techniques practiced in Horizon IV at Saruq al-Hadid created morphologically diverse hard-hammer percussion flakes. This contrasts with the morphological similarity of the backed microliths . One focSeveral SREs included debris from freehand core reduction, flake truncating, and microlith backing, showing that these techniques were practiced in the same reduction event. In these cases, both thick and thin blanks were struck from a core; sections of a thicker truncated flake (truncated pieces or segments) were progressively backing-retouched towards an intact former edge of the blank, which then became the chord of the finished microlith. This is referred to as ‘Saruq Strategy A’ . As attrThe more common strategy of microlith manufacture—‘Saruq Strategy B’—involved choosing flake blanks measuring less than about 8 mm thick see , thus avScars created during truncation/attrition are relatively large and irregularly spaced compared to the final backing scars, with more frequent platform crushing. About 77% of the microliths abandoned in manufacture were discarded during the early (truncating/attrition) or middle (attrition) stages of production ; Table 5The orientation of the microlith within the flake blank was determined by assessing the direction of propagation from features on the ventral surface. Almost all microliths were oriented parallel or oblique to the direction of flake blank propagation, with the blank’s lateral margin forming the chord . The disMost backing debris identified in the assemblage derived from the truncating/attrition stages of manufacture, including planar and perverse flakes. Planar backing flakes usually ended in an axial termination, are usually wider than long , and havThe outline of microliths abandoned during the attrition stage tend to be irregular, with PFAs spaced apart from each other along the backed edge. The platform margin is in some cases somewhat ‘notched’ from using a relatively narrow-ended indentor and delivering the blow back slightly from the platform edge . As withBacking flakes were initiated from one platform edge, creating single-backed microliths, or directly opposed platform edges, creating double-backed microliths . Single-In final stage finishing, the microlith was carefully manipulated and the points of applied force were spaced closer together than during the attrition stage. The delicacy of many finished microliths may indicate that final-stage backing was accomplished by anvil-supported pressure-flaking, rather than percussion (see ). On manRaw material colours of finished microliths are broadly similar to other artefact types, including early stage microliths, although a greater proportion of finished microliths are made from ‘other’ chert/chalcedony materials  of the late-stage Saruq al-Hadid microliths had straight chords; most (62%) curved inward, outward, or were a sinuous mixture of the two . This reThe shapes of the backed edges of early-stage microliths were irregular, reflecting the less-controlled percussion technique used in Step 1 attrition. In contrast, many of the late-stage microliths were expertly-backed and show a consistency in shape that suggests ‘style’. Some are symmetrical, with a half-moon shape, but a more common stylistic variant is classified as ‘scalene’. Scalene microliths are asymmetrical, with the shorter backed leg meeting the longer backed leg at an angle of about 110–130 degrees. The angle is abrupt on many examples, but this shape grades into artefacts with a similar asymmetry but a less-accentuated angle .2 = 0.00073) or chord length (R2 = 0.01993), suggesting that microliths were shaped to similar proportions regardless of blank size.Asymmetry can be assessed empirically by calculating the Maximum Width Position (MWP), or the location of the widest point of the microlith as a proportion of the total length (after ). On a pVariation in the ‘tip cross sectional area’ (TCSA) may distinguish between the stone armatures of different types of hunting/fighting weapons . TCSA isThe metrical variation at Saruq al-Hadid can be contrasted with Australian microliths because both technologies involved the production of flake blanks using hard-hammer percussion. The Australian method was similar to Saruq Strategy B (pers obs. MWM) and involved less invasive attrition during blank shaping than that seen in Saruq Strategy A. Australian microliths are metrically more similar to the early-stage manufacturing rejects from Saruq al-Hadid than the final microliths , suggestAlthough a blade-based technology with relatively large backed microliths dates from 30,000–33,000 years ago in Oman , this teThe expression of stone-flaking technology varies markedly at southeastern Arabian sites of the subsequent periods. For instance, backed microliths are absent and lithic artefacts and production debris are rare on many sedentary settlement sites of the Bronze and Iron Ages. Large-scale excavations produced very small lithic assemblages at sites such as Tell Abraq  are tenThe function of backed microliths in these various lithic traditions remains a matter of debate. Reviewing the long-term use of obsidian geometric microliths in northeastern Africa and southern Arabia by societies with diverse subsistence practices, Khalidi et al. simply note that they were ‘[u]sed to make composite tools whose function remains unconfirmed’ (: 81) TheIn contrast, a non-agricultural function is proposed for the Iron Age microliths from HAS1 in southern Oman , despiteAn agricultural use does not seem likely for the small backed microliths from Saruq al-Hadid, given the site’s desert environment and their occurrence in a midden dominated by the remains of hunted wild animals, in which remains of cereals were extremely scarce : Table 4Table 4. th–8th Century BCE reliefs from Yemen [Elsewhere we have argued that the backed microliths at Saruq al-Hadid principally functioned as armatures for arrows . This idom Yemen .The backed microliths from Saruq al-Hadid span the mid-second millennium BC and thus occur alongside the first documented metal arrowheads in southeastern Arabia . If theThe Saruq al-Hadid lithic reduction technology reflects a relatively simple, least-effort approach to core reduction, but flake backing demonstrates a high degree of technical skill. This is also true of the Tihamah sites, where microliths were made on flakes from a least-effort bipolar core reduction technique , 81, andExcavations at Saruq al-Hadid have produced a large assemblage of securely provenanced stone tools from the Wadi Suq/Late Bronze Age, ca. 1750–1300 BCE. The stone tools were made and discarded in the context of a dense midden containing wild oryx, gazelle, and camel bone, as well as the remains of domesticated goat and sheep, fish, birds, and other small animals.Chert for flaked-stone tools was procured as small cobbles from a variety of distant primary geological outcrops, and scavenged from nearby stone artefact scatters, and the materials were transported to the site after minimal assaying at the source. Transport costs were low because the stones were so small. At Saruq al-Hadid they were reduced into flakes through a simple freehand or anvil-supported hard-hammer percussion technique. Cores were rotated frequently as they were reduced and the reduction strategy was least-effort, done in response to the developing morphology of the cores rather than through a hierarchical series of flaking stages. Thin chert or chalcedony plates were retouched bifacially by hard-hammer percussion to create tablet knives. Some of the larger flakes, as well as the tablet knives, were truncated by striking the face in the middle, creating angular pieces with steep edges, perhaps for use as tools. Some flakes were unifacially retouched. The approach to this aspect of the reduction technology was ad hoc and relatively low-skilled, but higher skill levels are reflected in microlith manufacture. Flakes from ad hoc reduction were selected for the production of backed microliths. The early stages of microlith production often involved substantial attrition by anvil-supported hard-hammer percussion. Final stage backing was far more controlled and frequently involved a delicate double-backing technique, possibly accomplished using pressure, that often resulted in a distinctive ‘domed’ backed edge profile. The stoneworkers were more concerned with the widths and thicknesses of the microliths than the lengths, and the repetition of certain shapes—particularly scalene triangles—suggests attention to microlith ‘style’.A picture is now emerging of a broadly-contemporary Bronze Age regional interaction sphere involving backed microliths, likely hafted as projectile points. Similar backed microliths were produced in a band from Africa and Egypt, through Arabia and the Levant, to Gujarat in India and Luristan in Iran. Although the technologies used to produce blanks for microliths included different forms of ad hoc knapping, such as the direct percussion method at Saruq al-Hadid and the bipolar method on the Tihamah coast, highly technical blank production methods were used at Harappan sites in India. The varying environmental and cultural contexts of this Bronze Age microlith technology—as well as the varied methods of producing them—may indicate that stone-tipped arrows played a role in social signalling , 97. ThiS1 Table(DOCX)Click here for additional data file.


Hospital overcrowding is a growing problem worldwide. Studies demonstrated that up to 40% to 67% of hospitalizations of residents in nursing homes may be avoidable, causing health and economic damages. Furthermore, research shows that for non-critical patients there are arguably no differences between home and hospital recovery in terms of health outcomes, with a preference for home settings in most patients. During COVID-19 pandemic, telemedicine and homecare increased its range of possible intervention, allowing efficient and cost-effective processes of care. Transdermal sensors are indeed a cheap and easy to use alternative to conventional instruments, allowing a continuously operative and ready-to-use tool to care providers. This systematic review aims to map the application fields of these technologies, demonstrating their accuracy and assessing their cost-effectiveness in chronically ill home-assisted patients.Articles were retrieved from Scopus, Web of Science, and PubMed. The dominance ranking matrix (DRM) tool was applied to allow a qualitative synthesis of the studies. Incremental net benefits (INBs) were estimated and meta-analysis was implemented to pool INBs across studies. A comparison between wearables and conventional tools accuracy was simultaneously carried out through a literature review.The database search identified 1156 publications of which six articles were considered eligible for the meta-analysis. According to DRM, 80% of evaluated studies showed the cost-effectiveness of wearable devices. The pooled INB of wearables over conventional measurement was estimated at US$1280 (95% CI US$952 - US$2849). In 85% of evaluated wearables the accuracy resulted comparable to conventional measurement tools.Wearables performances resulted as accurate as conventional methods and their application cost-effective. A continuous measurement of parameters may relate to a better process of care for chronically ill outpatients.• Wearables are a cheap and accurate alternative to conventional life parameters measurement tools.• Technology evolution might soon reduce the pressure on hospitals, changing the care process of chronically ill outpatients allowing continuous evaluation of their health status.


The left ventricular aneurysm is a pathological condition defined as an akinetic or dyskinetic area of the left ventricle (LV) wall associated with reduced ejection fraction. The most common surgical technique to reconstruct a left ventricular aneurysm is endoventricular patch plasty (Dor procedure). In this case, endoventricular reconstruction of the left ventricular aneurysm using a double-layer extracellular matrix was performed. One of the most common surgical solutions for reconstructing a sizable left ventricle aneurysm is the endoventricular patch technique (Dor procedure). It improves the ventricle size and geometry, reduces wall stress and paradoxical movement, and increases the LV ejection fraction. Commonly used materials as a patch for reconstructing the LV aneurysm are Dacron, bovine pericardium and Teflon. We present our experience in reconstructing the apical LV aneurysm using a double-layer extracellular matrix  endoventricular patch.The left ventricular aneurysm is a pathological condition defined as an akinetic or dyskinetic area of the left ventricle (LV) wall associated with reduced ejection fractionA 61-year-old male was admitted to the hospital due to dyspnea symptoms, sharp chest pain during physical activity and profuse sweating. He had a history of ST-elevation myocardial infarction (STEMI) two years earlier, when he underwent primary percutaneous coronary intervention with implantation of two drug-eluting stents in the left anterior descending artery. The postprocedural period was uneventful.Cardio-specific enzymes (high-sensitivity troponin T and CK-MB) were in the referent range at admission to the hospital. Transthoracic echocardiography  revealed a dyskinetic apical segment of the left ventricle (LV) and compression of the lateral apical wall and apical segment by an organized thrombotic mass measuring 110 × 47mm . EjectioThe surgical procedure was performed through a median sternotomy. Cardio-pulmonary bypass was instituted by ascending aorta and right atrial appendage cannulation. A blood cardioplegic solution was used to arrest the heart. A giant LV apical aneurysm was found after extensive dissection of the pericardial adhesions . Longituth postoperative day.During the early postoperative period, the patient had a short episode of disorientation, which was medically treated. The remainder of the postoperative period was uneventful, and the patient was discharged from the hospital on the 7The control ECG-gated CT scan performed 30 days after the surgical procedure showed left pleural effusion without new pseudoaneurysm and local complications of the reconstructed ventricle . The 600. Progressive heart failure, persistent angina, thromboembolism and uncontrolled recurrent ventricular arrhythmias indicate surgical reconstruction. The primary aim of surgical treatment is LV “reshaping”, which improves cardiac function, symptoms and life expectancy. In the late 1980s, cardiac surgeon Vincent Dor developed the new surgical concept of LV aneurysm reconstruction using an endoventricular Dacron or pericardium patch. This technique has four advantages: it excludes the akinetic segment of the interventricular septum; restores the physiological geometry of the ventricular cavity; preserves the left anterior descending artery for coronary bypass; and eliminates the need for external prosthetic materials, which can cause persistent pericardial adhesions. The routine reconstruction of the LV wall is performed using an autologous, homologous or synthetic material. The main disadvantages of autologous or bovine pericardium are postprocedural fibrosis, thickening, and calcification. They may result in pseudoaneurysm formation, tissue retraction and rupture after the surgical repair. In addition, a synthetic material such as woven nylon (Dacron) could promote reactive inflammation and increase the risk of endocarditis,6. After implantation, the material becomes incorporated by fibrotic encapsulation and cannot fully restore the functionality of the regional tissue.Less than 5% of patients after transmural myocardial infarction develop LV aneurysm-8. Yanagawa et al. showed initial experience with interventricular repair using extracellular matrix. However, the short-term period (207±211 days) was uneventful. Patients with congenital heart disease who underwent cardiac surgery to reconstruct a pulmonary artery, right ventricular outflow tract, ascending aorta, and heart valve had no evidence of patch-related complications in the medium term. There is no evidence of long-term results after LV reconstruction using an extracellular matrix patch. McCready et al. present long-term results after carotid artery reconstruction using multilayer extracellular patch to increase 0.3% of new formed pseudoaneurysms during 72 of months follow-up.The novel biological material, an extracellular matrix, has been introduced in surgery due to its positive characteristics , which has been increasingly used in recent years. Tissue remodelling and regeneration are shown in preclinical experiments and clinical practice. Pathohistological examination revealed that the extracellular matrix was replaced by organized collagen, neovascularization and reendothelization, we performed a double-layer Proxicor patch to reconstruct the LV aneurysm.Because of these characteristics, we decided to use the extracellular matrix as an endoventricular patch to reconstruct the LV. In addition, due to the risk of postoperative rupture and pseudoaneurysm formation, which were described as an early postoperative complicationThe extracellular matrix can be used as a substitute for a Dacron, bovine and autologous pericardium in the endoventricular reconstruction of the left ventricle aneurysm. In addition, the double-layer surgical technique could be implemented to increase the patch strength and prevent potential adverse events.


The contribution of dysbiotic gut microbiota configuration is essential when making reference to the metabolic disorders by increasing energy. It is important to understand that the gut microbiota induced metabolic disease mechanisms and inflammations. Thus it is imperative to have an insight into the state of all chronic subclinical inflammations influencing disease outcomes. However, from the emerging studies, there still exist inconsistencies in the findings of such studies. While making the best out of the reasons for inconsistencies of the findings, this review is designed to make a clear spell out as to the inconsistence of gut microbiota with respect to diabetes. It considered gut-virome alterations and diabetes and gut-bacteriome-gut-virome-alterations and diabetes as confounding factors. The review further explained some study design strategies that will spontaneously eliminate any potential confounding factors to lead to a more evidence based diabetic-gut microbiota medicine. Lipopolysaccharide (LPS) pro-inflammatory, metabolic endotoxemia and diet/gut microbiota insulin-resistance and low-grade systemic inflammation induced by gut microbiota can trigger pro-inflammatory cytokines in insulin-resistance, consequently, leading to the diabetic condition. While diet influences the gut microbiota, the consequences are mainly the constant high levels of pro-inflammatory cytokines in the circulatory system. Of recent, dietary natural products have been shown to be anti-diabetic. The effects of resveratrol on the gut showed an improved lipid profile, anti-inflammatory properties and ameliorated the endotoxemia, tight junction and glucose intolerance. The functional medicinal approaches started with the experiment that involves replication of obese phenotypes of human discordant twin donors to mice through fecal microbiota transplantation (FMT)  and mitochondrial mutations  is one of the chronic metabolic diseases with a high prevalence worldwide. One out of every 3 adult Americans may develop diabetes by 2050 . Once NF-kB is translocated into the nucleus by degradation induced proteasomes, it activates the inflammatory cytokine responses. For an early factor in the establishment of insulin resistance, JNK and IKK must be activated by insulin receptor substrate (IRSs) serine phosphorylation /MyD88 adapter-like protein (MAL). MAL will then activate IL-1 receptor associated kinase (IRAK), TNF receptor-associated factor (TRAF6), and transform growth factors such as B-associated kinase 1 (TAK1), JNK and IKK complexes. Specifically, IKK complex will converge NF-In metabolic endotoxemia, the administration of anti-inflammatory agents, 5-aminosalicylic acid have been proven efficacious in restoring the gut barrier. It reduces tissue microbiota dysbiosis, thereby inhibiting the onset of inflammation in some metabolic syndrome . By comparing the bacteriome, virome and viral-bacterial correlations, the ObT2 were seen with a complete gut viral diversity and richness. Furthermore, intensive transkingdom correlations that occur between viruses and bacteria in lean controls and ObT2 were found to be significantly decreased. The common virus include; the phages of Clostridia among ObT2 against the control group  are negatively associated with GDM. The negative correlations mean glucose intolerance, inflammation and adiposity GDM women , an idea with probiotics would confer diabetes prevention and improvement  is induced by expression of butyrate produced. The differentiation and IL-10 production is modulated by propionate. Insulin resistance is improved via reduction of macrophage infiltration in adipose tissue by Treg cells  was administered. Some gut protective effects such as anti-inflammatory properties improvement, the lipid profile, ameliorated endotoxemia, intestinal barrier defects and glucose intolerance were observed (Chen et al. One recent study showed that a modified gut microbial composition reduces the proportion of Metformin has an effect on entero-endocrine hormone, bile acid metabolism and gut microbiome alteration in patients with T2DM. Due to its complex effects; lowering glucose, which is attributed to the activation of AMPK and antagonism of glucagon mediated elevation of cAMP in hepatocytes, a possible novel therapeutic for T2DM is ensured. The therapeutic effects of metformin are relative to the mode of administering on patients. Intravenously does not improve glucose metabolism. In contrast, orally taken of metformin archived relevant therapeutically blood concentrations. The prolonged pharmacokinetics within GI tract that metformin exhibits due to the small polyvalent cation at physiological pH is achieved via oral administration (Napolitano et al. Faecalibacterium, Akkermansia muciniphila and Lachnospira species. Despite the establishment of natural products and their bioactive properties as effective in modulating a normal gut microbiota, the mechanism of the metabolism ought to be investigated.Another beverage that is studied to reduce the postprandial glycemic response of bread is pomegranate polyphenols. This was not achievable when given as supplement and the extract. While some studies proposed insufficient mixing in the stomach and intestine could be the likely results, further study is required. Later in the postprandial period, microbial metabolites from pomegranate polyphenols modulate sugar metabolism. When consumed with a digestible carbohydrate such as bread, due to its polyphenols, it can reduce postprandial blood glucose spikes. The metabolic effects were seen in the reduction of the glucose IAUC by one-third (Kerimi et al. In conclusion, we recognised the power of gut microbiota and its related dysbiosis to form metabolic syndromes and disorders. The insulin resistance mechanism is active once passively depending on gut microbiota. Genetic modulation of the gut microbial metabolites and vaccine intervention are among the most recent strategies being developed in addition to anti-inflammatory agents for therapeutics of chronic metabolic diseases. Once the trialogue occurring among nutritional status, gut microbiota and immune system are elucidated, the number of breakthrough interventions will probably lead to a lifetime novel therapeutic opportunities for chronic metabolic diseases. Thus, the mechanistic roots of the ground breaking therapeutic strategies should be designed to target the host immune and nutrient-sensing pathways. This will enable us to synthesize novel innovative interventions that could lead to new treatments of chronic metabolic diseases. This review made emphasis on looking inwardly as to the conditions in which participants are recruited to take part in gut microbiota study. While the review based its argument on gut-virome alteration and gut-bacteria-gut-viral alterations induced confounding factors in studies focused on gut manipulating microbiota reversing diabetic complications, there is need to establish confounding-free state of art research design that will lead a consistent mega-studies and establish evidence based medicine. They recommended the study designs be directed so they can determine the association between diabetic patients’ biochemistry, haematology, metabolomics, metagenomics and proteomics to eliminate the possible confounding factors in the study.


To compare mechanical properties of 3D-printed and milled poly-ether-ether-ketone (PEEK) materials. To define post-production treatments to enhance biocompatibility of 3D-printed PEEK.Standardised PEEK samples were produced via milling and fused-deposition-modelling 3D-printing. To evaluate mechanical properties, tensile strength, maximum flexural strength, fracture toughness, and micro-hardness were measured.3D printed samples were sandblasted with 50 or 125 μm aluminium oxide beads to increase biocompatibility.Scanning electron microscopy (SEM) evaluated microstructure of 3D-printed and sandblasted samples, estimating surface roughness at scales from 1mm-1μm.Cell adhesion on 3D printed and sandblasted materials was evaluated by culturing primary human endothelial cells and osteoblasts  and evaluating cell growth over 48 h.3D printed materials had lower tensile strength, flexural strength, and fracture toughness, but higher micro-hardness.SEM analysis of 3D-printed surfaces showed sandblasting with 125 and 50 μm silica particles removed printing defects and created roughened surfaces for increased HUVEC and HOBs uniform cell adhesion and distribution. No cytotoxicity was observed over a 48h period, and all cells demonstrated >95% viability.3D-printing of PEEK is an emerging technology with clear advantages over milling in maxillofacial implant production. Nonetheless, this manufacturing modality may produce 3D printed PEEK devices with lower mechanical resistance parameters compared to milled PEEK but with values compatible with natural bone. PEEK has poor osteoconductivity and ability to osseointegrate. Sandblasting is an inexpensive modality to remove irregular surface defects and create uniform micro-rough surfaces supporting cell attachment and potentially enhancing integration of PEEK implants with host tissue. Biomaterials, Polyetheretherketone, CAD-CAM, Biocompatibility, Surgery. The gold standard reconstructive treatment is autologous bone transplantation. However, autologous grafts have drawbacks such as limited supply, donor site comorbidity, and unpredictable resorption during healing. There is also no aesthetically satisfactory donor site for critical-sized, geometrically complex craniofacial defects. These challenges encouraged the development of tissue engineering by utilising alloplastic grafts to address the problems , 2.Poly-ether-ether-ketone (PEEK) is a high-temperature thermoplastic polymer which demonstrates excellent chemical resistance to solvents except highly concentrated acids and is considered insoluble in biological fluids. PEEK’s implant radiolucency inside the body is beneficial as it demonstrates high resistance to electron beam and gamma radiation . This me3, and strong strain and fatigue resistance , Mechanical testing demonstrated that 3D printed materials had lower tensile strength  or large  aluminium particles smoothened and abated the irregularities creating a rough micro topography less than 100 microns . However, other studies have used 40, 50 and 60 mm/s. Wang –80 mm/s ; and the–80 mm/s . This ca4.3Both FDM PEEK and Milled PEEK were tested and evaluated for tensile strength, 3-point flexural strength, fracture toughness and Vickers hardness.et al. have suggested that this difference is due to injection moulding introducing external pressures which reduces internal defects and improves the density of parts [As Tables of parts . Other sof parts , 51. OurBy observing the path of the crack propagation using numerical simulation specific FDM processes can increase the fracture toughness of PEEK. This is achieved by depositing filament along the same trajectories that mechanical stresses are applied to; providing the material with extra reinforcement . FDM proBoth FDM PEEK and milled PEEK demonstrate tensile strength, flexural strength, fracture toughness and Vickers hardness values close to those of natural cortical bone, supporting PEEK’s applications as a bone replacement material. This includes applications in clinical dentistry, including different types of crowns, maxillofacial prosthesis, fixed partial dentures and removable partial dentures . PEEK ca4.4et al. pointed out the importance of eliminating the printing patterns as cells tend to reside in the deep valley of the printing patterns and lead to a heterogeneous cell distribution [Han ribution . The eliAn evenly distributed surface roughness was also created through sandblasting. Sandblasting has demonstrated the ability to produce an enhanced surface roughness which promotes osteoconduction, bone to implant contact and increased removal torque; thus supporting sandblasted PEEK’s viability as a bone implant .et al. demonstrated that sandblasted ceramic filled PEEK dental implants were able to osseointegrate in 9 experimental dogs; concluding that the aluminium oxide particle blasting created a PEEK surface topography which can promote the migration, distribution, and proliferation of osteoblasts to the surface-a crucial aspect to osseointegration. The study suggested this can create contact osteogenesis which could give potential to continuous bone remodelling under cyclical loading, with bone density statistics comparable to those of Titanium [Previous studies confirmed the cytocompatibility of sandblasted PEEK , 69. TheTitanium . MoreoveTitanium . Other sTitanium , 75. Thiet al. showed grooves and increased surface roughness have shown to be factors that support the adhesion and accumulation of cells, further emphasising the benefits of sandblasting and FDM production [As seen in the SEM analysis , the FDModuction .5In this current study it can be concluded that the data obtained revealed that 3D-printing of PEEK generated objects with substantially lower mechanical properties  compared to Milled PEEK. However, FDM PEEK mechanical properties remain in a range very similar to natural cortical bone, and thus both types of PEEK can be considered a valid replacement to other bone substitute biomaterials such as Titanium. The closer mechanical strength values of both types of PEEK with bone increases the viability of PEEK’s clinical applications with potential for less stress shielding effects, better osseointegration as a scaffold, and less chance of implant failure. The current lack of significant studies evaluating the mechanical properties of FDM PEEK and PEEK produced by Milling processes is an aspect that this research adds value too and has furthered.FDM PEEK was successfully 3D printed with promising results in accuracy, diameter, and thickness, increasing the potential of FDM printing for designing complex patient-bespoke objects with increased efficiency and less waste of material. The high print accuracy demonstrated in this study is an important aspect when considering the potential of complex geometric PEEK implants. It is also beneficial to consider the outcomes of utilising different FDM printing parameters when printing PEEK devices, and how to apply these to different clinical applications when balancing mechanical strength and interconnected porosity.The SEM image confirmed the effect of sandblasting treatment on eliminating the printing patterns and creating homogenous roughness, thus proving us a useful, cost-effective method of increasing PEEK biocompatibility. This study also signified the advantages of sandblasting as a form of mechanical treatment enhancing surface topography, as the results showed increased osteoblast and HUVEC cell adhesion with treated surfaces when compared to untreated. This can again give a potential cost-effective method of enhancing PEEK surface biocompatibility which may give clues to potential osseointegrative capabilities for PEEK scaffolds.It is worth considering the limitations of this study with guide to future work. Furthermore, future studies may consider adding FTIR or X-ray diffraction analyses to the 3D-printed and Milled PEEK specimens to understand the differences in crystallinity in the two production methods and how this can affect the mechanical strength of the material , 77, 78 Despite a small sample size, we have standardised in-vitro experimental conditions to minimise this issue. The relatively small standard deviation observed in most groups seems to confirm this and thus we have assumed that the data are likely normally distributed as typical in in-vitro setups .Further detailed examination of surface chemical compositions will be necessary to ensure no contamination was caused by the surface treatment. The successful cell adhesion and zero toxicity suggests there were no toxic contaminants present. However, it may also be beneficial in future studies to undertake more comprehensive industrial cleaning processes post-surface treatment and consequent biocompatibility assessment to ensure the absence of surface contaminants.Finally, in vivo studies under physiological load using 3D printed PEEK will be necessary to evaluate osseintegration and long-term success of implants.In conclusion, PEEK has many current applications in dentistry and maxillofacial reconstructive surgery and 3D printing significantly expands the repertoire of possible designs with great promises for the manufacture of bespoke medical devices and implants.Dr Neil Limaye: Conceived and designed the experiments; Performed the experiments; Analyzed and interpreted the data; Wrote the paper.Dr Lorenzo Veschini: Conceived and designed the experiments; Analyzed and interpreted the data; Wrote the paper.Professor Trevor Coward: Conceived and designed the experiments; Contributed reagents, materials, analysis tools or data; Wrote the paper.This research did not receive any specific grant from funding agencies in the public, commercial, or not-for-profit sectors.Data included in article/supp. material/referenced in article.The authors declare no conflict of interest.No additional information is available for this paper.


BackgroundCornulin is an epidermal differentiation marker and a stress-related protein. Its expression patterns are likely to reflect the multi-step tumorigenesis process of cSCC, given its role as a tumor suppressor. The aim of this study is to evaluate the utility of Cornulin as a prognosticator for cutaneous squamous cell carcinoma (cSCC). Specifically, the correlation between Cornulin expression and the clinicopathological parameter of lymph node involvement , which plays a major role in determining cSCC prognosis and recurrence. We predicted that Cornulin expression declines as cSCC tumors metastasize to regional lymph nodes.MethodologyTissue samples of cSCC lesions of variable nodal involvement status were stained using immunohistochemistry, and high-resolution images were acquired. Aperio ImageScope software (Leica Biosystems) equipped with a positive-pixel-counting algorithm was used to quantify the staining intensity. Subsequently, Cornulin immunoreactivity was calculated as a Histo-score (H-score) value, which is based on the staining intensity and the percentage of positively stained cells. Mean H-scores were compared between groups using an unpaired t-test.ResultsA significant inverse correlation was found between Cornulin expression levels and metastasis to the lymph nodes. Specifically, primary tumors with metastasis to regional lymph nodes (N1) exhibited 9.5-fold decrease in Cornulin immunoreactivity compared to the primary tumor samples without lymph node involvement (N0).ConclusionCornulin was found to be significantly downregulated in primary tumors with lymph node metastases. Detection assays to measure Cornulin expression in cSCC primary tumors might aid in determining the nodal status in these patients and possibly help determine cases of occult lymph node metastasis or micrometastasis. Future clinical studies are needed to help establish Cornulin’s role in enhancing the predictive power of histopathological examination and improving survival rates for patients suffering from this type of skin cancer. Cornulin is a squamous cell-specific protein that has recently been associated with several human disease processes. Encoded by the CRNN gene located on chromosome 1q21 within the epidermal differentiation complex fused-gene complex, Cornulin is highly expressed in mature keratinocytes, especially in the granular and lower cornified cell layers of the epidermis . TherefoWhile Cornulin is found to be upregulated in acute stress responses, it is notably downregulated in several malignancies involving the squamous cell epithelium. Studies have documented this downward trend in Cornulin expression in cervical SCC ,12, oralGiven that cutaneous SCC (cSCC) is a relatively common skin cancer that can metastasize and recur, we aimed to characterize Cornulin as a molecular biomarker that can potentially aid in monitoring disease progression and relapse, as well as predicting clinical outcomes for cSCC patients, by examining the correlation between Cornulin expression and the clinical stages as indicated by the TNM staging of cSCC based on tumor size, regional lymph node involvement, and metastasis. Our findings suggest that Cornulin might serve as an indicator for lymph node involvement status in cases of cutaneous squamous cell carcinoma.Immunohistochemistry staining of tissue samplesThe tissue samples for this experiment were obtained from de-identified tissue microarrays  and included 16 primary tumors from head and neck, trunk and extremities sites. Eight primary tumors were associated with no lymph node metastasis (N0), and eight primary tumors were associated with lymph node metastasis (N1). Additionally, serial sections of a normal skin tissue sample were used as equalizing control in each IHC experiment. During the immunohistochemistry staining and analysis, the experimenters were blinded to the TNM classification and clinical stages of the tissue samples.Immunohistochemistry staining of tissue microarray slides consisted of an antigen retrieval step using citric acid followed by blocking with 5% bovine serum albumin (BSA). The tissue samples were then labeled with a rabbit IgG polyclonal primary antibody against Cornulin at 1:200 dilution , followed by staining with anti-rabbit HRP-conjugated secondary antibody at 1:1000 dilution . The tissue samples were incubated with 3,3' Diaminobenzidine (DAB) chromogenic substrate and counterstained with Hematoxylin, then mounted with a coverslip for preservation.Quantitative analysis of Cornulin expressionFollowing the IHC experiment protocol, the tissue samples were imaged with a high-resolution Nikon A1R  inverted microscope at 10x magnification. Aperio ImageScope software  was used for computer-assisted image analysis to eliminate interobserver bias and subjectivity that is often seen in the manual assessment of IHC staining intensity. Quantification of immunoreactivity in the tissue region of interest was accomplished using the positive pixel counting v9 algorithm in Aperio ImageScope software. Manual selection of regions of interest  in each tissue sample was included, while irrelevant regions were excluded . Strong (Nsp), medium (Np), weak (Nwp) positive pixels, and negative pixels were assigned red, orange, yellow, and blue colors, respectively, by the Aperio ImageScope  software. The algorithm generated the number of Nwp, Np, and Nsp positive pixels; the total number of positive and negative pixels ; and the percentage of total positivity , which allowed for the calculation of the percentage of the weak, medium, and strong positivity by dividing Nwp, Np, and Nsp pixels, respectively, by NTotal pixels. Immunoreactivity was measured based on two parameters, the percentage of positively stained epithelial cells and the staining intensity. Histo-score (H-score) was calculated by adding the percentage of positive cells multiplied by the weighted intensity of staining. H-score = (1 x % weak positivity) + (2 x % medium positivity) + (3 x % strong positivity). The percentage of positive cells (% staining) was derived from the percentage of total positivity  values produced by the Aperio ImageScope software. The average H-scores for each set of clinicopathological parameters were calculated along with the standard error of the mean (SEM), followed by statistical analysis using a two-sample unpaired t-test.Cornulin expression in cutaneous squamous cell carcinomaAs a late epidermal differentiation marker, Cornulin is abundant in the upper layers of the epidermis . We haveCorrelation between Cornulin expression and lymph node involvement in cSCCCornulin immunohistochemical detection combined with computer-assisted image analysis showed that tissue samples with metastases to the lymph nodes, N1, exhibit a significant decline in Cornulin expression when compared to tissue samples without nodal metastases, N0 Figure .The mean H-score for Cornulin immunoreactivity was 1.05 for samples with N0 status and 0.11 for samples with N1 status. On average, there was a 9.5-fold downregulation in Cornulin expression associated with the N1 tissue samples. The correlation between Cornulin expression and the nodal status of cSCC was statistically significant (P = 0.0006) Figure .Cutaneous squamous cell carcinoma is the second most common malignant tumor of the skin in White patients and the most common malignant skin tumor in Black patients . ImportaCurrently, the evaluation of prognosis in cSCC patients is heavily reliant on the TNM classification to assess the tumor size (T), regional lymph node involvement (N), and distant metastases (M) parameters. However, patients with similar TNM staging classification often have different clinical outcomes, highlighting the fact that tumors that share the same TNM clinical staging at the time of diagnosis might have the variable potential for proliferation, invasiveness, and metastasis. Cutaneous squamous cell carcinoma tends to spread first to regional lymph nodes before it metastasizes to distal tissue sites . MoreoveGiven the fact that metastatic cSCC is associated with a high mortality rate (70%) and high recurrence rates (15%-28%), determining if a cSCC tumor has metastasized to regional lymph nodes is a crucial step in patient management -22. EstaIn our study, we predicted that Cornulin expression patterns are likely to reflect the multi-step carcinogenesis process of cSCC, given its role as a tumor suppressor . Indeed,Cornulin was found to be significantly downregulated in primary tumors with lymph node metastasis, a major contributor to cSCC progression to the advanced clinical stages. Altogether, Cornulin expression can potentially serve as a valuable prognosticator for cSCC patients as it correlates with metastasis to regional lymph nodes, a key factor in determining the prognosis and recurrence of cutaneous squamous cell carcinoma.


The pathophysiology of chronic thromboembolic pulmonary hypertension (CTEPH) is largely unknown. Although pulmonary endarterectomy (PEA) is potentially curative, inoperable patients and persistent pulmonary hypertension (PH) following surgery remain a significant problem. In this study, we aim to describe the histopathological characteristics of CTEPH and explore the potential relationship between pulmonary arterial lesions, radiological parameters, and clinical manifestations. Endarterectomized tissues from 81 consecutive patients of CTEPH were carefully collected, sectioned, and examined by experienced pathologists. Pertinent clinical and radiological data were obtained from medical records and operative reports. Neointima, fresh/organized thrombi, recanalized regions, and atherosclerotic lesions were microscopically examined as previously described. Thrombi and atherosclerosis were dominant in UCSD classification level I PEA materials, while recanalized neo-vessels were more frequently observed in UCSD classification level III cases. Degenerative changes of the extracellular matrix were also noticed in the vascular bed. Atherosclerotic lesions were more frequently observed in cases with higher ratio of the pulmonary artery diameter to ascending aorta diameter (PA/AA) reflected by computed tomographic pulmonary arterial scanning. Furthermore, the removal of pulmonary artery complex lesions (with the combination of three to four types of lesions) by PEA was associated with lower postoperative mean pulmonary arterial pressure (mPAP) and decreased incidences of persistent PH. Our study demonstrates that the histopathological features of CTEPH are strongly linked with clinical manifestations and the postoperative outcome after PEA. These data may provide possible evidence for further studies in searching for appropriate causal factors underlying this disease. Chronic thromboembolic pulmonary hypertension (CTEPH) is considered as a result of unresolved organized thrombus in proximal pulmonary arteries after acute pulmonary embolism (PE) and is accompanied with a secondary vasculopathy, leading to increased pulmonary vascular resistance (PVR) and progressive right heart failure . CTEPH iDuring the PEA procedure, the fibrotic organized thromboembolic tissue is carefully excised, following the inside of the artery down to lobar, segmental, or subsegmental branches ,4. EfforIn this study, we morphometrically described the pathological characteristics of removed specimens from CTEPH patients who underwent PEA and sought to investigate the possible relationship between major vessel lesions and clinical manifestations.The study was carried out at China–Japan Friendship Hospital, a national referral center for CTEPH in China. Between December 2016 and March 2021, 272 patients were diagnosed with CTEPH based on well-defined standards .−1·cm−5. Persistent PH was defined as mPAP ≥ 30 mmHg after PEA before patients were extubated [Clinical information was extracted from their medical records. For each patient, age at the time of surgery, sex, heart function, pulmonary artery pressure (PAP), and documented history of acute pulmonary embolism/deep vein thrombosis (PE/DVT) and thrombophilia were carefully recorded. Contrast-enhanced computed tomographic pulmonary arterial scanning (CTPA) was performed on patients after admission; the pulmonary artery diameters (PA) and ascending aorta diameters (AA) were measured at the level of the bifurcation of the pulmonary trunk on the axis view to calculate PA/AA. Right heart catheterization measurement was obtained at baseline (pre-PEA) and 1–3 days after PEA in the intensive care unit prior to removal of the intraoperative Swan-Ganz catheters (post-PEA). PVR was calculated by mean pulmonary arterial pressure (mPAP)- mean pulmonary capillary wedge pressure (mPCWP)/cardiac output (CO) multiplied by 80 for dynes·sxtubated .The UCSD classification system was used to describe the macroscopical characteristics of PEA specimens according to the anatomical location: level 0—no evidence of thromboembolic disease, level I—thromboembolic disease starts in the main pulmonary arteries , level II—thromboembolic disease starts at the level of lobar or intermediate pulmonary arteries, level III—thromboembolic disease starts at segmental pulmonary arteries, and level IV—thromboembolic disease starts at subsegmental branches only . The most-test (parametric) was used to compare the difference between the two groups. Nonparametric chi-square tests or Fisher exact tests were used to compare proportions. Results with p < 0.05 were considered statistically significant.Statistical analyses were performed using GraphPad Prism 8.0 software . Data were presented as medians with first and third quartiles (Q1–Q3), means ± standard deviations (SDs), or absolute numbers and percentages of patients. If data were normally distributed and with similar variances, the Student’s The clinical characteristics of the 81 CTEPH patients were summarized in p < 0.0001) and PVR  levels in CTEPH patients. Perioperative mortality was observed in 4.94% of our study population due to heart failure (two patients), lung reperfusion oedema (one patient), and sepsis (one patient).PEA significantly reduced the mPAP , level II (34.57%), and level III (11.11%), whereas level IV disease was not present in our study population . Sectionn = 80, 98.77%), which was characterized by the accumulation of α-smooth muscle actin (α-SMA)-positive cells (n = 25) of all patients  in PEA-removed materials: hyalinization was observed in 62 patients’ specimens (76.54%), presenting as a homogeneous distribution of collagen fibers A; mucoidp = 0.0432; As a long-term consequence of elevated PAP, pulmonary artery dilation has been recognized as a common feature of PAH and CTEPH . The ratp = 0.0312, Eight specimens (9.88%) in our study were identified with only neointima or thrombus formation, while most cases were observed with more than one type of the four basic lesions A. HoweveIn the present study, we described the histopathological characteristics of the endarterectomized specimens from patients with CTEPH and analyzed the association between thromboembolic vasculopathy and pulmonary hypertension. The incidences of the four basic lesions were comparable with the report from Quark et al. . NeointiAtherosclerotic lesions containing foam cells and cholesterol crystals were first noted to present in CTEPH vascular beds by Bernard and Yi in 2007 . Later ip = 0.0987 by the chi-square test, data not shown). Based on this fact, a potential explanation for the discrepancy in hemodynamic changes between patients with simple or complex lesions may be the inaccessibility of occlusions further than segmental arteries in cases with distal thromboembolic diseases. Further investigation is required to elucidate how specific types of lesions would contribute to the maintenance of pulmonary hypertension in CTEPH. Our data showed that the removal of obstructed pulmonary materials with three or more types of lesions was associated with lower postoperative mPAP, although no difference was noticed at the baseline. We then noticed that distal disease (UCSD classification level III) was less frequently found in cases with complex lesions than simple lesions  was noticed in cases with recanalization, although without statistical significance. In addition, recanalized lesions were less frequently identified in patients with persistent pulmonary hypertension . These data are consistent with earlier reports, and we presume that the non-significance may be due to the wide variation in postoperative hemodynamic parameters.Previous studies have demonstrated that the presence of histopathological recanalized lesions is a predictor of better hemodynamic improvement and lower mortality in short- and long-term follow-ups after PEA ,9. In ouIn our study, the mean time from the onset of PH symptoms to PEA was much longer than what was reported based on European registries , and thiThe current study described the end-stage histopathological characteristics of major pulmonary arteries in CTEPH without following the sequence of events from early thrombus, as pulmonary endarterectomized tissues only provided a cross-sectional view of the late changes of CTEPH. Therefore, further studies are required to investigate the pathophysiology of this thromboembolic disease. Next, we are aware that, although we demonstrated the correlation between histological features and clinical manifestations, the evidence was not strong enough to establish casual relationships. In addition, histopathological examinations can only provide a descriptive analysis after PEA was accomplished. Based on these facts, the present results scarcely have an impact on the optimal therapeutic choices in the treatment of CTEPH and cannot help the multidisciplinary team (MDT) to decide which group of patients would benefit more from PEA. However, we believe that our findings may provide valuable bases for further studies, which may contribute to elucidating the underlying pathophysiology of CTEPH.Furthermore, a long-term follow-up study after patients were discharged from the hospital was not provided. As Corsico et al. demonstrated that, after surviving the perioperative period, the early hemodynamic benefits of PEA remained largely unchanged over 5 years , and as In summary, we described the detailed histological characteristics of CTEPH and revealed innovative associations between pulmonary vasculopathy and clinical manifestations. Our data provided the first evidence suggesting that atherosclerotic lesion formation is correlated with pulmonary artery dilation in CTEPH. Furthermore, we showed that the removal of occluded tissues composed of complex lesions is related to lower postoperative mPAP. Further studies are needed to address the nature of this association and evaluate its implications for the clinical management of CTEPH.


Gout is one of the most common inflammatory arthropathies in the developed world. However, involvement of the spine is relatively rare, and other sinister differential diagnoses will need to be considered. We describe an unusual case of gouty tophi deposition within the spine in an elderly patient presenting with signs and symptoms of acute cord compression. Important differential diagnoses that need to be excluded include bony metastases from underlying malignancy and other infective/inflammatory causes. Early recognition of imaging findings can avoid delayed or inappropriate medical treatment. A 70-year-old male with longstanding history of multiple joint pain and soft tissue swelling, and multiple other co-morbidities including diabetes, hypertension and chronic renal failure, presents with sudden onset of upper and lower limb weakness. Physical examination was worrisome for spinal cord compression.A lateral view of the cervical spine showed partial collapse of the C5 and C6 vertebral bodies with complete loss of the C5/6 disc space .Contrast-enhanced computed tomography (CT) of the cervical and thoracic spine was performed with images obtained in pre-contrast, post contrast and bone window to further delineate the pathology. On the axial images in bone window, a bulging soft tissue mass causing narrowing of spinal canal and obliteration of bilateral neural foramina at the C5 level T1-weighted and T2-weighted intermediate signal lesion centered at the intervening disc space  or pseudogout, can present in a similar fashion as gout, but can be differentiated radiologically by the presence of chondrocalcinosis commonly in the hands, wrist or knees. CPPD also seldomly has a soft tissue component as seen in goutA CT-guided bone biopsy of T10 and T11 vertebral bodies was performed and histology showed foreign body granulomatous reaction towards eosinophilic fibrillary material, suggestive of tophaceous gout. Patient was referred to the rheumatologist and neurosurgeon for further management during this in-patient stay, but unfortunately succumbed to hospital acquired pneumonia before further treatment for his gout and cord compression could be administered.Gouty arthropathy is an asymmetrical polyarticular disease, with the foot being the most common in location and in particular the first metatarsophalangeal joint. The next most common regions are the hands and wrists, followed by the elbow and knee joints. Michael et al has reported that most cases (80%) involved only one region of the spine, and around 25% affected the cervical spine only. To our knowledge, only around 10 or so cervical gout cases with images have been reported so far.There can be involvement of any segment of the spine, including the vertebral bodies, pedicles, lamina, ligaments, epidural, and intradural spaces. Lumbar spinal involvement is most commonly affected in the spine. Tophi are predominantly juxta-articular in location. Occasionally, it may arise from within the bone, giving rise to lytic, expansile, well-defined lesions with thin sclerotic margins.Gouty tophi may vary considerably in radiological manifestation, depending on their histological composition. They commonly appear as round or oval ill-defined hyperdense mass lesions in comparison with normal soft tissue. Small lesions can also be radiographically occult if less than 10 mm in size. The principle and value of DECT is its ability to differentiate densities based on their relative absorption of X-rays at different photon energy levels (commonly at 80 and 140 kVp), which enables quantification of gouty deposits and demonstration of non-crystalline tophus components with greater resolution.Dual-energy computed tomography (DECT) is an increasingly common investigation for evaluating tophaceous gout deposition.T1-weighted intermediate signal and homogeneous enhancement post-contrast. Differences in its calcium concentration can give rise to variable and T2-weighted signal. Bone weakening can lead to pathological fractures and locoregional mass effect/compression by the tophi, as demonstrated in this caseGouty tophi on MRI typically shows  Disease presentation in atypical locations may warrant a bone or soft tissue biopsy to exclude other sinister causes.Histological diagnosis is confirmed with microscopic monosodium urate crystals in synovial fluid or within the tophi.Conservative medical treatment can be considered in patients without concomitant neurological deficits, after excluding spinal infection or early reversible causes. Nonsteroidal antiinflammatory agents and steroids have been proven to be effective for acute pain control. Surgery may be considered when there is a need for relief of neurologic symptoms, but long-term management still relies on adequate medical therapy.This case illustrates a common disease entity presenting in an atypical location and presentation with complications.Involvement of the vertebral column is uncommon in gouty arthropathy, and causing acute cord compression is even rarer. Important common differential diagnoses that needs to be excluded are bony metastases from underlying malignancy, and other infective/inflammatory changes which warrant more urgent management.


Foot ulceration is a major complication of diabetes mellitus, which results in significant human suffering and a major burden on healthcare systems. The cause of impaired wound healing in diabetic patients is multifactorial with contributions from hyperglycaemia, impaired vascularization and neuropathy. Patients with non-healing diabetic ulcers may require amputation, creating an urgent need for new reparative treatments. Delivery of stem cells may be a promising approach to enhance wound healing because of their paracrine properties, including the secretion of angiogenic, immunomodulatory and anti-inflammatory factors. While a number of different cell types have been studied, the therapeutic use of mesenchymal stromal cells (MSCs) has been widely reported to improve delayed wound healing. However, topical administration of MSCs via direct injection has several disadvantages, including low cell viability and poor cell localization at the wound bed. To this end, various biomaterial conformations have emerged as MSC delivery vehicles to enhance cell viability and persistence at the site of implantation. This paper discusses biomaterial-based MSCs therapies in diabetic wound healing and highlights the low conversion rate to clinical trials and commercially available therapeutic products. Diabetic foot ulcers are the main cause of amputation in patients with diabetes mellitus, resulting in high healthcare costs, reduced quality of life and increased mortality. The 10th edition of the International Diabetes Federation Atlas has reported that the number of patients suffering from diabetes mellitus in 2021 was 536.6 million, and there will be approximately 783.2 million adults with diabetes by 2045 , 7574, 7In terms of utilisation of sponge scaffolds in diabetic wound healing applications, collagen and chitosan-based sponge scaffolds are the most commonly used MSC carriers. O’Loughlin, et al. have developed a collagen sponge scaffold using a freeze-drying method. Compared to no-treatment control, the topical administration of allogeneic BM-MSCs through a collagen sponge scaffold augmented wound closure and increased angiogenesis after transplantation for 7 days in the diabetic rabbit wound . A collaFig. Fibrous scaffolds are mainly developed by an electrospinning method to create three-dimensional constructs consisting of fibres at microscale or nanoscale level to mimic the architecture of natural human tissue , chemical  or enzymatic  decellularization procedures to remove cellular components . CommonlSeveral studies have investigated the use of decellularized grafts as a MSC delivery platform. One of these studies has shown that rat AD-MSCs seeded on a decellularized graft secreted various cytokines  that stimulated the migration and proliferation of fibroblasts, eventually resulting in improved wound closure  in a diabetic rat model . In anot6 cells/cm2) encapsulated in a sodium alginate hydrogel was topically administrated to the foot ulcer of a patient with type 2 diabetes mellitus. The wound healed completely after 3 weeks of treatment, with improved foot pain, no toxicity and no relapse during the subsequent 6 months follow-up visit [Currently, 13 clinical trials using scaffold-based delivery of MSCs to treat diabetic patients with foot ulcers are registered with ClinicalTrials.gov  , 95, 111Besides defining optimal cell source, there are many other bottlenecks hindering the translation of results obtained at the laboratory bench to the clinic and ultimately to the marketplace. These include the absence of a globally shared standard manufacturing process and the high level of regulatory diversifications across countries which create crucial challenges for international clinical trial collaborations and cross-country marketing procedures . In addiMSCs are attractive therapeutic agents for use in diabetic wound healing, whilst biodegradable scaffolds provide a physiologically relevant three-dimensional environment for their optimal growth and localisation at wound bed. Pre-clinical studies have demonstrated that delivering MSCs via a variety of different scaffolds to diabetic wounds accelerates healing and enhances skin regeneration. In spite of this, there is limited clinical trial data available on the use of scaffold-based MSC delivery for treatment of diabetic wounds. Issues regarding safety, efficacy and cost of the MSC-scaffold graft in clinical applications should be considered from an early stage of research and properly addressed. Therefore, an interdisciplinary approach involving biomedical scientists, clinicians, biomaterial engineers, industry and regulators will be necessary to develop a scaffold-based cell therapy product suitable for clinical application.