Editorial

Fibrous histiocytoma is a tumor composed of a mixture of fibroblastic and histiocytic cells. These lesions most often arise on the skin, but may rarely occur in soft deep tissues. The diagnosis of FH may be clinically difficult when the lesion is located in the deep tissues, and is frequently confirmed after local excision. The most important diagnostic necessity is the separation of this tumor from aggressive forms of fibrohistiocytic neoplasms. We present a unique case of malignant fibrous histiocytoma developing in left buccal mucosa very near to the surgical margin from which a benign fibrous histiocytoma of the mandible was excised 3 years earlier in a 31 year old female. Clinical and histopathological evidence were not sufficient to establish link between these two processes. This article aims to describe the case and discuss the findings.     

Cystic Granular Cell Ameloblastoma

Ameloblastoma is a locally aggressive benign epithelial odontogenic tumor, while unicystic ameloblastoma is a relatively less aggressive variant. Although rare in unicystic or cystic ameloblastoma, granular cell change in ameloblastoma is a recognized phenomenon. The purpose of the present article is to report a case of cystic granular cell ameloblastoma in 34-year old female.     

Imaging of desmoplastic infantile ganglioglioma: a spectroscopic viewpoint

Purpose  Desmoplastic infantile gangliogliomas (DIG) are rare benign intracranial neoplasms of early childhood with involvement of superficial cerebral cortex and leptomeninges. The purpose of the study was to determine the alterations in metabolite ratios occurring in the neoplasm and combine with magnetic resonance (MR) imaging features to narrow down the diagnosis. Methods  MR imaging sequences include T1- and T2-weighted sequences, fluid-attenuated inversion recovery sequences, and post-gadolinium-contrast T1-weighted imaging. Single-voxel short TE ¹H MR spectroscopy was used to study the changes in metabolite ratios in the tumor. Results  Comparison of metabolite ratios between normal brain tissue and tumor-affected region showed lower N-acetyl aspartate to creatine (Cr; 1.58 vs.1.28), higher choline to Cr (0.82 vs.2.03), and no significant change in myo-inositol to Cr (0.42 vs.0.39). Conclusion  MR spectroscopy and imaging provide valuable information in the diagnosis of DIG.     

A preliminary study on plasma concentration achieved following intrapterygomandibular space injection of dexamethasone as a route of drug delivery with lignocaine inferior alveolar nerve block–correlation of clinical effects

Purpose

To determine the quantity of dexamethasone plasma concentration achieved following intrapterygomandibular space injection of dexamethasone when co-administered with inferior alveolar nerve block correlating with the clinical effects in the postoperative phase.

Objective

A preliminary prospective study to evaluate the dexamethasone plasma concentration achieved following intrapterygomandibular space injection of dexamethasone with 2% lignocaine inferior alveolar nerve block to achieve hemi-mandibular anesthesia for minor oral surgical procedures and derive clinical correlations.

Background

Dexamethasone is a glucocorticoid, chiefly used for the management of postsurgical sequelae like trismus and swelling in maxillofacial surgical practice. Conventionally, parenteral dexamethasone is administered via intravenous or intramuscular route. Intrapterygomandibular space injection is a novel route of steroid delivery described in literature. For minor oral surgical procedures in maxillofacial surgical practice requiring inferior alveolar nerve block, dexamethasone can be administered along with local anesthetic through a single injection as a mixture (twin mix).

Methods

Prospective double-blind randomized clinical trial was designed to evaluative plasma concentration of dexamethasone achieved following injection of a freshly prepared mixture of 1.8 ml of 2% lignocaine with adrenaline (1:200000) and 1 ml (4 mg) dexamethasone [2.8 ml solution of twin mix] in the pterygomandibular space. The 30 candidates included for the trial were randomly split into three study groups (ten each)—(1) control group (C); (2) intramuscular group (IM); (3) intraspace group (IS).

Results

The mean plasma dexamethasone concentration at 30 min postinjection in group IM was 226.41?±?48.67 ng/ml and for IS group it was 209.67?±?88.13 ng/ml. Post hoc (Bonferroni-Holm test) intergroup comparison for plasma dexamethasone concentration (IM and IS) was found statistically insignificant (P?=?0.605).

Conclusion

Intraspace route of drug administration can be utilized to deliver dexamethasonized local anesthetics safely with predictable clinical effects in the patients requiring mandibular minor oral surgery under local anesthesia.

     

Thermally stable La2LiSbO6:Mn4+,Mg2+ far-red emitting phosphors with over 90% internal quantum efficiency for plant growth LEDs

In this paper, we reported on the high-efficiency and thermally-stable La₂LiSbO₆:Mn⁴⁺,Mg²⁺ (LLS:Mn⁴⁺,Mg²⁺) far-red emitting phosphors. Under 338 nm excitation, the composition-optimized LLS:0.3%Mn⁴⁺,1.6%Mg²⁺ phosphors which were made up of [SbO₆], [LiO₆], and [LaO₈] polyhedrons, showed intense far-red emissions peaking at 712 nm (²E_g → ⁴A_2g transition) with internal quantum efficiency as high as 92%. The LLS:0.3%Mn⁴⁺,1.6%Mg²⁺ phosphors also exhibited high thermal stability, and the emission intensity at 423 K only reduced by 42% compared with its initial value at 303 K. The far-red light-emitting device has also been made by using the LLS:0.3%Mn⁴⁺,1.6%Mg²⁺ phosphors and a 365 nm emitting InGaN chip, which can emit far-red light that is visible to the naked eye. Importantly, the emission spectrum of the LLS:0.3%Mn⁴⁺,1.6%Mg²⁺ phosphors can match well with the absorption spectrum of phytochrome P_FR, indicating the potential of these phosphors to be used in plant growth light-emitting diodes.

Double perovskite La₂LiSbO₆:Mn⁴⁺,Mg²⁺ far-red emitting phosphors with internal quantum efficiency as high as 92% and good thermal stability were developed for plant growth LEDs.     

Preparation,characterization, and luminescence properties of double perovskite SrLaMgSbO6:Mn4+ far-red emitting phosphors for indoor plant growth lighting

Mn⁴⁺-activated SrLaMgSbO₆ far-red emitting phosphors with double perovskite structure were prepared by traditional solid-state reaction. The research on the crystal structure of the SrLaMgSbO₆:0.8%Mn⁴⁺ (SLMS:0.8%Mn⁴⁺) phosphors showed that the as-prepared sample was made up of two polyhedrons, [SbO₆] and [MgO₆]. Under the excitation of 333 nm, the SLMS:0.8%Mn⁴⁺ phosphors exhibited an intense far-red emission in the 625–800 nm wavelength range with CIE chromaticity coordinates of (0.733, 0.268), which could match well with the absorption spectrum of phytochrome P_FR. The optimal concentration of Mn⁴⁺ ions in the SLMS:Mn⁴⁺ phosphors was 0.8 mol%. Importantly, the as-prepared SLMS:0.8%Mn⁴⁺ phosphors had an internal quantum efficiency of 35%. The thermal stability of SLMS:0.8%Mn⁴⁺ phosphors was also investigated, and the activation energy was found to be 0.3 eV. Thus, the Mn⁴⁺-activated SLMS phosphors have great potential to serve as far-red emitting phosphors in indoor plant growth lighting.

Novel far-red emitting double perovskite SrLaMgSbO₆:Mn⁴⁺ phosphors were prepared and their photoluminescence properties were studied for applications in indoor plant growth lighting.     

Structural elucidation of NASICON (Na3Al2P3O12) based glass electrolyte materials: effective influence of boron and gallium

Understanding the conductivity variations induced by compositional changes in sodium super ionic conducting (NASICON) glass materials is highly relevant for applications such as solid electrolytes for sodium (Na) ion batteries. In the research reported in this paper, NASICON-based NCAP glass (Na_2.8Ca_0.1Al₂P₃O₁₂) was selected as the parent glass. The present study demonstrates the changes in the Na⁺ ion conductivity of NCAP bulk glass with the substitution of boron (NCABP: Na_2.8Ca_0.1Al₂B_0.5P_2.7O₁₂) and gallium (NCAGP: Na_2.8Ca_0.1Al₂Ga_0.5P_2.7O₁₂) for phosphorus and the resulting structural variations found in the glass network. For a detailed structural analysis of NCAP, NCABP and NCAGP glasses, micro-Raman and magic angle spinning-nuclear magnetic resonance (MAS-NMR) spectroscopic techniques (for ³¹P, ²⁷Al, ²³Na, ¹¹B and ⁷¹Ga nuclei) were used. The Raman spectrum revealed that the NCAP glass structure is more analogous to the AlPO₄ mesoporous glass structure. The ³¹P MAS-NMR spectrum illustrated that the NCAP glass structure consists of a high concentration of Q⁰ (3Al) units, followed by Q⁰ (2Al) units. The ²⁷Al MAS-NMR spectrum indicates that alumina exists at five different sites, which include AlO₄ units surrounded by AlO₆ units, Al(OP)₄, Al(OP)₅, Al(OAl)₆ and Al(OP)₆, in the NCAP glass structure. The ³¹P, ²⁷Al and ¹¹B MAS-NMR spectra of the NCABP glass revealed the absence of B–O–Al linkages and the presence of B₃–O–B₄–O–P₄ linkages which further leads to the formation of borate and borophosphate domains. The ⁷¹Ga MAS-NMR spectrum suggests that gallium cations in the NCAGP glass compete with the alumina cations and occupy four (GaO₄), five (GaO₅) and six (GaO₆) coordinated sites. The Raman spectrum of NCAGP glass indicates that sodium cations have also been substituted by gallium cations in the NCAP glass structure. From impedance analysis, the dc conductivity of the NCAP glass (∼3.13 × 10⁻⁸ S cm⁻¹) is slightly decreased with the substitution of gallium (∼2.27 × 10⁻⁸ S cm⁻¹) but considerably decreased with the substitution of boron (∼1.46 × 10⁻⁸ S cm⁻¹). The variation in the conductivity values are described based on the structural changes of NCAP glass with the substitution of gallium and boron.

Understanding the conductivity variations induced by compositional changes in sodium super ionic conducting (NASICON) glass materials is highly relevant for applications such as solid electrolytes for sodium (Na) ion batteries.     

Postoperative Cardiac Arrhythmias in Children

Opinion statement