Case Report and Literature Review of Acute Spontaneous Intraspinal Epidural Hematoma (SSEH) Secondary to Myeloproliferative Disease.

Background: Spontaneous spinal epidural hematoma (SSEH) presenting in the context of JAK2 V617F-positive myeloproliferative neoplasms is a rare condition, characterized by the compression of the spinal cord leading to various symptoms. The etiology, pathogenesis, and optimal treatment strategies for this condition remain undetermined. The occurrence of spontaneous spinal epidural hematoma (SSEH) in the context of JAK2 V617F-positive myeloproliferative neoplasms (MPNs) represents a rare manifestation. Magnetic Resonance Imaging (MRI) plays a crucial role in the definitive diagnosis of this condition. With a good understanding of the pathogenic characteristics and clinical presentations of this disease, a diagnosis can be reasonably made, even in the absence of MRI, based on physical examinations indicating the affected area. Once diagnosed, immediate surgery is recommended to attempt the restoration of spinal cord function. Postoperatively, the use of hydroxyurea has proven effective in disease control. Case Presentation: We report a case of a 65-year-old male patient who presented with progressive lumbar back pain and bilateral lower limb paralysis lasting for 36 hours. CT imaging revealed an intraspinal lesion at the L1-3 level, and genetic testing confirmed the presence of the JAK2V617F mutation. Following surgery, there was a significant recovery of sensory and motor function in the lower limbs. At one-year follow-up, the patient demonstrated good functional status, and blood tests indicated a platelet count within the normal range. Conclusion: The presented case adds to the existing literature on SSEH by highlighting the association with myeloproliferative neoplasms (MPNs), as evidenced by the JAK2V617F mutation. MPNs constitute a group of hematologic malignancies, and the association with SSEH is a rare occurrence. The exact interplay between MPNs and SSEH warrants further investigation, as the underlying mechanisms linking these conditions remain elusive. The case also underscores the importance of a multidisciplinary approach, involving hematologists and neurosurgeons, in the comprehensive management of such complex cases.

Potential factors promoting the natural regeneration of Larix principis-rupprechtii in North China.

Natural regeneration plays an important role in species diversity and evolution. Exploring the causes of variation in regeneration dynamics can provide key insights into the factors affecting regeneration. However, the relationship between the regeneration of Larix principis-rupprechtii and environmental factors in North China has remained unexplored. In this study, 14 plots were established based on the three extents of regenerated plant numbers in Shanxi Province. Redundancy analysis determined that environmental factors (topography, stand structure, soil property, and litter) affected natural regeneration. Structural equation modeling identified the most important direct and indirect factors that affected L. principis-rupprechtii natural regeneration. Litter thickness, canopy density, and adult tree diameter at breast height were positively correlated with natural regeneration. Aspect and total nitrogen volume were negatively associated with natural regeneration. Additionally, there was no significant correlation between natural regeneration and other environmental factors (altitude, slope, adult tree height, stand density, soil water content, SOC, total P, available N, available P, or soil enzyme). Further artificial intervention measures should be considered to promote plantation regeneration. These findings provide an effective basis for future forest restorations and sustainable management.

Abnormal obturator artery with ipsilateral inferior epigastric artery passed behind the femoral vein / Arteria obturatriz anómala con arteria epigástrica inferior ipsilateral que cruza posterior a la vena femoral

SUMMARY: Clear awareness of the vascular variations is critical in surgeries, which may cause massive hemorrhage during surgical procedures. During educational dissection of a male cadaver, we encountered a combined variation of the left obturator artery and ipsilateral aberrant inferior epigastric artery. The left obturator artery originated from the external iliac artery, then coursed inward, adherent to the superior pubic ramus. The left inferior epigastric artery originated from the femoral artery, and coursed behind the femoral vein. These anatomical variations shown in one person were extremely rare. This is particularly true with regard to these variations while performing pelvic and inguinal region surgeries.

El conocimiento claro de las variaciones vasculares es fundamental en las cirugías, ya que pueden causar una hemorragia masiva durante los procedimientos quirúrgicos. Durante la disección educativa de un cadáver de sexo masculino, encontramos una variación combinada de la arteria obturatriz izquierda y la arteria epigástrica inferior ipsilateral aberrante. La arteria obturatriz izquierda se originaba en la arteria ilíaca externa, luego discurrió hacia medial, adhiriéndose a la rama púbica superior. La arteria epigástrica inferior izquierda se originaba en la arteria femoral y discurría por detrás de la vena femoral. Estas variaciones anatómicas mostradas en una sola persona son extremadamente raras. Esto es importante de conocer estas variaciones cuando se realizan cirugías de las regiones pélvica e inguinal.

Characteristics and factors influencing the natural regeneration of Larix principis-rupprechtii seedlings in northern China.

Larix principis-rupprechtii is an important and widely distributed species in the mountains of northern China. However, it has inefficient natural regeneration in many stands and difficulty recruiting seedlings and saplings. In this study, we selected six plots with improved naturally-regenerated L. principis-rupprechtii seedlings. A point pattern analysis (pair-correlation function) was applied to identify the spatial distribution pattern and correlation between adult trees and regenerated seedlings mapped through X/Y coordinates. Several possible influencing factors of L. principis-rupprechtii seedlings' natural regeneration were also investigated. The results showed that the spatial distribution patterns of Larix principis-rupprechtii seedlings were concentrated 0-5 m around adult trees when considering the main univariate distribution type of regeneration. There was a positive correlation at a scale of 1.5-4 m between seedlings and adult trees according to bivariate analyses. When the scale was increased, these relationships were no longer significant. Generally, adult trees raised regenerated L. principis-rupprechtii seedlings at a scale of 1.5-4 m. Principal component analysis showed that the understory herb diversity and litter layer had a negative correlation with the number of regenerated seedlings. There was also a weak relationship between regenerated numbers and canopy density. This study demonstrated that the main factors promoting natural regeneration were litter thickness, herb diversity, and the distance between adult trees and regenerated seedlings. Additionally, these findings will provide a basis for the late-stage and practical management of natural regeneration in northern China's mountain ranges.

Two-dimensional FeP@C nanosheets as a robust oxidase mimic for fluorescence detection of cysteine and Cu2.

In the past few years, the development of novel nanozymes with excellent performance has attracted increasing attention in biosensing. However, most of those nanozymes were found to possess peroxidase activity with the prerequisite of the presence of H2O2. In contrast, oxidase mimics can catalyze the oxidation of substrates without H2O2, delivering a higher signal-to-noise ratio than that of peroxidase mimics in practical applications. Herein, for the first time, two-dimensional (2D) nanosheets composed of iron phosphide embedded in a carbon matrix (FeP@C nanosheets) were found to demonstrate a robust oxidase-like property, different from those previously reported peroxidase mimics based on transition metal phosphides (TMPs). Based on this intriguing observation, the fluorescent substrate Amplex Red (AR) of peroxidase can be effectively oxidized by FeP@C nanosheets in the absence of H2O2. Benefiting from the oxidase-like enzymatic activity of the FeP@C nanosheets, a novel fluorescence sensing platform was developed for the detection of cysteine (Cys) and Cu2+. The outstanding performance of the 2D FeP@C nanosheets endows the proposed platform with superior sensitivity and selectivity compared to many previously reported approaches. Besides, the inherent features of simplicity, being label free, and low cost also allow this methodology to stand out among many other strategies, revealing its huge potential in practical analysis and detection applications.

High peroxidase-like activity realized by facile synthesis of FeS2 nanoparticles for sensitive colorimetric detection of H2O2 and glutathione.

In the last decades, enzyme mimics have been regarded as strong substitutes to natural enzymes. The construction of biosensors based on these enzyme mimics with competitive catalytic activity and substrate specificity has attracted a lot of research interest. Herein, for the first time, we investigated the capability of nanoscale FeS2 to serve as enzyme mimics. Then, a facile and effective biosensor is fabricated based on its intrinsic peroxidase-like catalytic activity. In the presence of H2O2, FeS2 nanoparticles (NPs) possess high peroxidase-like activity to 3,3',5,5'-tetramethylbenzidine (TMB) oxidation, which can be ascribed to the generation of hydroxyl radicals (·OH) from the H2O2 decomposition catalyzed by FeS2 NPs. As for TMB, the resulting Michaelis-Menten constant (Km) value of FeS2 NPs is found to be about 12 times lower than that of natural horseradish peroxidase (HRP), highlighting the superiority of FeS2 NPs. Based on these intriguing observations, a reliable colorimetric method is then developed for detection of H2O2 and glutathione (GSH) by a simple mix-and-detect strategy. The detection limits of H2O2 and GSH are as low as 0.91 µM and 0.15 µM (3σ/slope), respectively. Moreover, FeS2 NPs can also catalyse the photoluminescence (PL) substrate terephthalic acid (TA) under the assistance of H2O2. This work remarkably extends the utilization of FeS2 NPs in the construction of colorimetric and PL biosensors in the fields of biosensing, environmental monitoring, and medical diagnosis.

A Hybrid of FeS2 Nanoparticles Encapsulated by Two-Dimensional Carbon Sheets as Excellent Nanozymes for Colorimetric Glucose Detection.

Recently, the development of nanozymes with high catalytic performance is gaining more and more attention due to the ever-growing demands for their practical applications. The elaborate design of its morphology has demonstrated to be an effective approach to improve the performance of these nanozymes. Herein, a hybrid of iron disulfide nanoparticles (FeS2 NPs) encapsulated by two-dimensional (2D) carbon nanosheets (NSs), denoted as FeS2@C NSs, demonstrates both superior peroxidase-like activity and excellent stability. The incorporation of 2D carbon sheets endows the proposed FeS2@C nanozymes with high specific surface area, providing abundant active sites to facilitate the contact with substrates. Moreover, the embedded FeS2 NPs are kept from aggregation due to the encapsulation and confinement of 2D carbon sheets, avoiding the conventional failure of single-component nanozymes. Based on glucose oxidase (GOx) and the elaborately designed FeS2@C nanozymes, a colorimetric method for glucose detection is then developed with excellent simplicity and sensitivity. The detection limit of the sensing platform is as low as 0.19 µM for a glucose assay. More notably, this method can be successfully employed for the glucose assay in some real samples, indicating the great potential of this FeS2@C NS-based nanozymes in the fields of biotechnology and clinical diagnostics.

Controlled synthesis and alkaline earth ion binding of switchable formamidoxime-based crown ether analogs.

The partial positive charge of amide protons is used to promote macrocyclization and form crown-ether analogs. Their deprotonation generates very selective pH-switchable alkaline earth ion receptors only in the presence of an appropriate substrate.

Z-formamidoximes in molecular folding and macrocycles.

The formamidoxime configurational Z isomer coupled with the pyridylbiscarboxamide conformational codon were used to fold planar, curved structures. When embedded into macrocycles, this folded motif promotes dimerization through π-π stacking and hydrogen-bonding and the formation of tubules akin to molecular channels in the solid state.

Alkoxyamine-derived formamidines: configurational control and molecular folding.

N,N'-Disubstituted formamidines, and amidines in general, have very rich configurational, conformational, and tautomeric diversities. As part of an effort to incorporate alkoxyamine-derived formamidine units into foldamers, the first evidence for the isolation of the up-to-now unknown E isomer, the conditions for its exclusive formation, its stability and self-assembly properties, and its configurational isomerization to its much more common Z counterpart are reported. Considering the distinctly different H-bonding patterns displayed by both E and Z isomers, such configurational control may find applications in self-assembly, molecular recognition, and biomimetic systems.