Mean Size Research Articles

Electrospray-Scanning Mobility Particle Sizer (ES-SMPS) Technique: Superior Sizing and Multimodal Characterization of Colloidal Nanoparticles Compared to NTA and DLS.

This study primarily employed three techniques─electrospray-scanning mobility particle sizer (ES-SMPS), nanoparticle tracking analysis (NTA), and dynamic light scattering (DLS)─to assess multimodal samples. For monodisperse particles, both ES-SMPS (all sizes) and NTA (for particles larger than 40 nm) accurately determined the mean size, while DLS overestimated it. The ES-SMPS technique demonstrated precision in particle counting for multimodal samples, with a standard deviation of around 2.5-4%. Conversely, NTA's ability to count particles potentially leads to misinterpretation. The ES-SMPS approach could identify particle peaks in multimodal (bimodal, trimodal, and tetramodal) samples and show the relatively accurate position of the mode diameter. In contrast to ES-SMPS, DLS and NTA have weaknesses in characterizing multimodal samples. While NTA's performance depends on the optical properties of particles and cannot measure silica particles smaller than 30-40 nm, ES-SMPS is independent of light scattering and can handle particles as small as ∼13 nm. The ES-SMPS also excelled in separating particle peaks of the bimodal sample with a size interval gap of 10 nm, whereas NTA needs at least 20-50 nm depending on the particle type. To sum up, the ES-SMPS method performs better and provides more accurate measurements for characterizing multimodal samples compared to NTA and DLS.

Improving wear resistance of Ti6Al6V2Sn alloy by reinforcing AlBeSiTiV high-entropy alloy through microwave sintering

The present study examines the wear performance of microwave-sintered Ti6Al6V2Sn (Ti662) alloy reinforced with 15 wt% AlBeSiTiV High-Entropy Alloy (HEA). The AlBeSiTiV HEA is synthesized by ball milling at 250 rpm for 20 h, resulting in irregular fragments with a mean size of 15 µm and an FCC phase structure. The α-Ti grains decreased with increment of β -Ti grains upon adding HEA reinforcement with the Ti662 alloy. The Ti662/HEA composite exhibited 762 HV microhardness mainly due to refined grains through uniform dissipation in the sintering. The grains sized 0.597 µm on average. The pin-on-disc tribometer is employed to evaluate the wear rate of Ti662/HEA composite under varied process parameters such as applied load, sliding velocity, and sliding distance resulted in enhanced wear resistance through grain refinement, hindering effect, and superior interfacial bonding properties of reinforced HEA particles. Morphological analysis of the worn surfaces reveals wear mechanisms, including delamination, grooves, and the formation of oxide layers. These layers are developed due to the reinforcement of HEA with Ti662 alloy, serving as a protective film over the composite surface against wear.

Biomarkers of systemic treatment response: MR images of intratumoral fat deposition in colorectal liver metastases (CRLM) after chemotherapy.

Colorectal cancer cells containing mobile lipids are said to be an early indicator of chemotherapy effects. The objective of the study was to examine the frequency and clinical relevance of intratumoral fat deposition in colorectal liver metastases (CRLM) post-chemotherapy using dual-echo chemical shift gradient-echo magnetic resonance imaging (MRI). A retrospective analysis of 98 patients with CRLM diagnosed between 2017 and 2022 (69M, mean age 62.87 ± 10.73years old) who had an MRI after chemotherapy was performed. On dual-echo chemical shift gradient-echo MRI, intratumoral fat deposition of CRLM was evaluated. A signal intensity drop of ≥ 12% in opposed-phase images vs. in-phase images indicated intratumoral fat. After chemotherapy, the presence of fat deposition was correlated with patients' overall survival. Before and after chemotherapy, 0 (0%) and 29 (29.59%) patients exhibited intratumoral fat. The number of CRLM ranged from 1 to 25 with a median of 3 and a mean size of 32.58 ± 22.95mm. The groups had statistically different survival times. Overall survival was shorter for patients with intratumoral fat deposition in CRLM (32months (24-60, 95% CI)) than for patients without fat deposition in CRLM (48months (36-NA, 95% CI)). In our group, nearly 30% of CRLM patients exhibited intratumoral fat after chemotherapy. Patients with intratumoral fat deposition in CRLM have a shorter overall survival time. The presence of fat in CRLM correlates with a poor long-term prognosis.

A rapid segmentation and occlusion completion method for morphology analysis of packed granular particles considering uncertainty

Occlusions of granular particles in images significantly affect the accuracy of evaluating particle morphology for granular materials. In this study, a novel framework of SOLO-PCNet is proposed, which can automatically segment all the particles and predict the complete contours of the occluded particles in densely packed materials. Firstly, the instance segmentation model SOLOv2 is trained for the prediction of all the detectable particles. Then a self-supervised learning algorithm PCNet-M is introduced for the inference of the complete contours of the occluded particles so that the prediction of SOLOv2 can be directly input to PCNet-M for the subsequent completion. Thereafter, the particle morphology characteristics including elongation, equivalent mean size, convexity, and circularity are automatically calculated. Then, the evaluation metrics of the segmentation model and morphology characteristics are validated, and the results exhibit the strong generalization ability of the segmentation and completion tasks. Finally, the uncertainty of the completed contours with morphology properties is explored for reliable analysis. This study successfully acquires the complete contours for each particle and provides the foundation for evaluating the mechanical properties of the packed granular materials from individual particles.

Poly(lactic-co-glycolic) acid nanoparticles with thermoresponsive shell for sustained release of dexamethasone

Polymeric nanocarriers based on poly(lactide-co-glycolide) (PLGA) enable drug encapsulation while achieving increased solubility of hydrophobic drugs, enhanced plasmatic half-life, and protecting the drug from early degradation/metabolization. Nevertheless, it is still difficult to effectively regulate the drug release from nanocarriers. Covering the surface of PLGA nanoparticles (NPs) with a thermoresponsive shell may be the key factor for building drug delivery systems with temporal and spatial control. In this respect, PLGA NPs with a mean size of 212 nm, containing dexamethasone (Dex) (Dex/PLGA NPs) have been produced by the dialysis technique without the use of a surfactant. Then, the nanoparticles were covered with poly(N-isopropylacrylamide-co-4-vinyl pyridine) (PVP) by ionic interactions between the amine groups of the PVP and carboxylic groups of PLGA. FT-IR and XPS spectroscopy were used to identify the new functional groups introduced on the PLGA nanoparticles' surface. The assembly of PVP on the PLGA NPs was analyzed by monitoring the particle size with temperature, zeta potential, AFM, and TEM analysis. The in vitro drug delivery investigation showed that temperature has significant control over the release rate of Dex from PVP-coated PLGA NPs. The thermosensitive polymer is hydrated at temperatures lower than LCST (20 °C) and forms a gel around the nanoparticles slowing down the release rate of Dex. Above the LCST, PVP becomes hydrophobic, collapses, inducing a substantially slower and sustained release of Dex, with 84 % released at 200 h.

Access and usage of formal financial services among small-scale Cassava farmers for productivity in Enugu state, Nigeria.

Purpose: Access to financial resources has been identified as one of the ways of boosting farm output, and this can be achieved through improving access to and usage of formal financial services. The study thus evaluated the effects of financial inclusion on cassava production among small-scale farmers in Enugu state, Nigeria. Methodology: A multi-stage sampling technique was employed in the selection of 162 cassava farmers in Enugu State. The data collected were analyzed using descriptive statistics, multiple regression analysis, and Likert scale rating Technique. Finding: Empirical results showed that the average of all respondents who participated in the survey was 43 years and 62.35% of the total respondents were males. Additionally, the result showed mean household size (4.75), mean years of cassava farming experience (5.86 years), and mean farm size (0.45 hectares). The majority (88.30%) of the farmers had access to a formal financial institution and the average amount saved in the last 12 months was ₦162,154.32. The multiple regression analysis showed that socioeconomic characteristics influencing cassava output are household, farming experience, farm size, farm income, and input cost. Additionally, financial inclusion positively influenced cassava output through access to formal financial institutions and level of savings. Originality: The findings revealed the positive effect access and usage of formal financial services have on the economy. Therefore, the study recommends that farmers be encouraged to improve their usage of formal financial services such as improving their savings levels at banks and banks to reduce charges on formal financial services.

Impact of Rab27 on Melanoma Cell Invasion and sEV Secretion.

The migratory and invasive capabilities of melanoma cells contribute to metastasis. Therefore, targeting the genes driving these processes can support melanoma therapy. Rab27A and Rab27B contribute to tumor formation progression in many types of cancer through various mechanisms, including the secretion of small extracellular vesicles (sEVs). We explored the role of these GTPases in melanoma cell functioning in three RAB27A knockout (KO) cell lines (A375, DMBC12, and SkMel28) and a double RAB27A/B KO A375 cell line. The loss of RAB27A impaired the migration and invasion of DMBC12 and SkMel28 cells; however, the behavior of highly aggressive A375 cells was unaffected. The RAB27A/B double knockout moderately decreased the migratory capacity of A375 cells without disturbing their invasiveness. Additionally, the silencing of RAB27A did not affect the number and mean size of the sEVs, despite some alterations in the protein content of the vesicles. Both Rab27 isoforms can, at least partially, act independently. The potential role of Rab27A in the functioning of melanoma cells depends on the individual character of the cell line, but not on its basal expression, and seems to be unrelated to the secretion of sEVs.

Influence of smoking on cardiometabolic profile and surgical outcomes in patients with primary aldosteronism. A cohort study.

To evaluate the influence of smoking on cardiometabolic profile and surgical outcomes in patients with primary aldosteronism (PA). Multicenter retrospective study of patients with PA in 36 Spanish tertiary hospitals with available information on smoking habits (smokers and non-smokers [never smokers and ex-smokers]). A total of 881 patients were included, of whom 180 (20.4%) were classified as smokers and 701 as non-smokers. At diagnosis, smokers and non-smokers did not differ in blood pressure or serum potassium levels between. However, smokers had a higher prevalence of left ventricular hypertrophy (LVH) than non-smokers (OR 2.0, 95% CI 1.23 to 3.25), and smokers were more likely to have severe LVH than non-smokers (12.5% vs. 6.6%, P=0.164). A larger mean tumor size of the adrenal nodule/s was observed in the smoking group (18.6±9.66 vs. 15.8±8.66 mm, P=0.002). In addition, the odds of mild autonomous cortisol secretion (MACS) was greater in smokers than in non-smokers (OR 2.1, 95% CI 1.14 to 4.06), but these differences disappeared when adjusted for the size of the adrenal nodule/s (adjusted OR 1.6, 95% CI 0.76 to 3.37). The rate of biochemical and hypertension cure was similar in both groups; however, hypertension cure tended to be more frequent in the non-smoker group (41.2% vs 29.9%, P=0.076). Patients with PA who smoke have a higher prevalence of LVH and MACS and larger adrenal nodule/s than non-smokers. Smoking has no significant effect on the probability of hypertension response after adrenalectomy in patients with PA.

Determination of Size, Size Distribution, and Concentration of Nanoparticles Using ICP‐MS in the Context of SERS Substrates

ABSTRACTSurface enhanced Raman scattering (SERS) is a widely used vibrational spectroscopic technique employing metallic nanostructures to enhance an inherent Raman signal. This study aimed to develop a method for the characterization of SERS substrates in a single analysis by inductively coupled plasma mass spectrometry (ICP‐MS) equipped with the single particle module (spICP‐MS). For this development, the well‐known Lee‐Meisel protocol was selected as starting point to synthesize gold nanoparticles (AuNps) and silver nanoparticles (AgNps). A spICP‐MS method was successfully developed and gave the mean size, size distribution, and concentration of nanoparticles in only one single analysis. Reference techniques were used to confirm these results namely dynamic light scattering, transmission electron microscopy, and UV–Visible spectroscopy. Thanks to the ICP‐MS characterization, it was observed that AgNps synthesized by chemical reduction presented more variability than the AuNps. The dissolved elements concentration in the suspension was investigated. It appeared that reaction yields were close to 100% for the six syntheses. This analysis may be repeated over time to evaluate the suspension stability and monitor any potential degradation of Nps. To conclude, ICP‐MS is a powerful technique to characterize SERS substrates and could be an interesting alternative to other characterization techniques.

Клінічна характеристика та особливості хірургічного лікування пацієнтів із простими кістами нирок

Simple renal cysts are quite common in adults with an incidence that increases with age. Renal cysts are composed of enclosed liquid or semisolid fluid and are commonly identified through abdominal imaging. The purpose of this study was to compare the clinical and laboratory characteristics of patients with simple renal cysts who underwent aspiration sclerotherapy or laparoscopic resection and establish the association between these parameters. The research was conduc­ted on the basis of the urology department of the St. Panteleimon Hospital between 2021 and 2023, 46 patients who underwent surgical removal of a renal cysts were analyzed. The main methods of treating kidney cysts were aspiration sclerotherapy and laparoscopic unroofing. Patients were divided into groups depending on the treatment method (aspiration sclerothe­rapy or laparoscopic unroofing). In order to establish the differences, a comparative analysis was carried out by age, sex, results of clinical parameters, cyst localization and recurren­ces. The association between clinical parameters and treatment methods was assessed using Pearson’s χ2 test. Statistical analysis of the obtained data was carried out with the help of software packages SPSS v. 25.0 and EXCEL. There were 13 men (62 %) and 8 women (38 %) among patients who underwent lapa­roscopic unroofing. Right renal cysts were found in 8 patients (38 %), and left renal cysts were found in 13 patients (62 %). The mean age of the patients was 56±2.6 years. Among the patients undergoing aspiration sclerotherapy, there were 11 men (44 %) and 14 women (56 %). The right kidney cyst was found in 14 patients (56 %), and the left kidney cyst was found in 11 patients (44 %). The mean age of the patients was 63±2.2 years. The mean size of kidney cysts in patients who underwent laparoscopic unroofing was 70±3.6 mm. In patients undergoing aspiration sclerotherapy, the size of kidney cysts was 72±5.4 mm. There was no statistically significant difference in age, sex, and size of kidney cysts in patients who underwent aspiration sclerotherapy and laparoscopic unroofing. It was established that there was no statistically significant difference in age, sex, or size of renal cysts in patients undergoing surgical treatment. In patients after laparoscopic unroofing, relapses have not been established in the clinic. However, the frequency of recurrence in patients after aspiration sclerotherapy is 74±9 % of the total number of patients, which is a fairly high rate of recurrence of renal cysts. We found that laparoscopic unroofing was associated with a lower recurrence rate compared with aspiration sclerotherapy. It should be noted that laparoscopic unroofing is a more effective method of treatment compared to aspiration sclerotherapy. We emphasize that laparoscopy is a modern approach to renal cyst surgery, which not only reduces trauma, shortens the recovery time of patients, but also ensures high accuracy and efficiency of treatment.

Particle Size and Crystal habit Modification of Ammonium Perchlorate Using Cooling Sonocrystallization Process

AbstractAmmonium perchlorate (AP) is a widely used solid oxidizer in solid propellant formulations, with its particle size and crystal habit significantly affecting performance. Since controlling these properties remains challenging, this study employs an intensified crystallization strategy, specifically a cooling sonocrystallization process, to recrystallize AP to control and modify its particle size and crystal habit. The effects of solution concentration, sonication intensity, sonication pulse on/off recipe, and cooling rate on the recrystallization of AP are first investigated using a Taguchi L9 orthogonal array design. By understanding the main effect of these operating parameters, further sonocrystallization experiments are designed for process improvement. Compared with the unprocessed AP, the crystal habit and mean particle size of AP are considerably modified after cooling sonocrystallization, achieving a mean size of approximately 50 µm with a regular habit. Consistency in crystal structure and spectrometric properties between sonocrystallized and unprocessed AP was confirmed. Furthermore, the thermal properties and decomposition behavior of the sonocrystallized AP are analyzed, revealing improved exothermic characteristics. These results prove that cooling sonocrystallization is an efficient tool for producing AP particles and also holds the potential for preparing fine particles of other energetic materials.

Recurrence following microsurgical excision of third ventricular colloid cysts in a contemporary cohort of 84 patients

ObjectiveTo examine recurrence rates in patients undergoing microsurgical excision of colloid cysts of the third ventricle with long-term serial clinical and imaging follow up and to identify risk factors for cyst recurrence. MethodsIn this retrospective study, we analysed a single-surgeon cohort of 84 patients who underwent microsurgical excision of a third ventricular colloid cyst between 1994 and 2018 and who were followed for at least 12 months after surgery. The primary outcome of interest was recurrence (asymptomatic and symptomatic). ResultsThe mean age at surgery was 33.8 (range, 8-65 years). Out of 84 patients, 82 (97.6%) were symptomatic and 71 (84.5%) had obstructive hydrocephalus. The mean tumor size was 15.2 mm (range, 7-35 mm). A total or near total excision was achieved in 76 (90.5%) patients. The median clinical follow-up duration was 89.5 months (range, 12-340 months). 81 (96.4%) had follow up imaging. Overall, recurrence occurred in 25 (29.8%) cases, with 7 (8.3%) experiencing symptomatic recurrence. No specific risk factors for recurrence were identified. Longer follow-up was associated with a higher detection of recurrences. The 5-year recurrence free survival rate was 81.6%, which dropped to 66.5% at 10 years follow up. ConclusionPeriodic imaging surveillance is essential following excision of third ventricular colloid cysts to detect asymptomatic recurrences, as these lesions may recur several years after presumed total or near-total excision. Recurrences associated with clinical symptoms or demonstrated growth on serial follow-up require intervention; however, re-operation may be cautiously deferred in patients with stable asymptomatic recurrences.

Preparation and characterization of self-dispersive and reactive carbon black and its application in cotton fabric

This study aims to develop a self-dispersive and reactive carbon black (DRCB) to improve its application in cotton fabric. CB was functionalized with γ-aminopropyl triethoxysilane (KH550) and then grafted with as-synthesized compound to obtain aqueous phase DRCB. FTIR analysis confirmed the successful grafting of as-synthesized compound onto KH550-modified CB surface. The weight grafting of DRCB on DRCB-15 % dyed cotton fabric was approximately 15.18 %, with a half weight grafting time of around 17 min. TEM observation demonstrated that DRCB had a core-shell structure with the mean sizes of 36.02 ± 4.30 nm. Particle size analysis revealed that DRCB had smaller average aggregate size of 110.3 nm and higher zeta potential of −33.7 mV than CB, indicating that DRCB had much better dispersion in aqueous media than CB. Cotton fabric was effectively dyed with DRCB, providing excellent color depth of 60 (K/S value) with dry rubbing and wet rubbing/washing color fastness of Grade 4 and Grade 3, respectively. DRCB dyed cotton fabric exhibited outstanding anti-UV and anti-static properties, with no significant difference in softness and tensile property before and after dyeing. This research proposed a new method to solve nanoparticle agglomeration and prepare textile dyes with excellent self-dispersivity and reactivity.

Deciphering the enigma of glomus tumors: A case series

Glomus tumors are rare contributing to less than two percent of all soft tissue tumors. Given the rarity of this tumor, there is a possibility of low suspicion and a missed clinical diagnosis. This case series suggests diagnostic and morphological clues for early diagnosis of this tumor.This retrospective study includes nine interesting cases of glomus tumors from January 2015 to January 2024. Data was tabulated and analysed by descriptive statistics using Microsoft Excel 2016. In this series the glomus tumors showed a mean age of (37.67± 17.5 years). Male to female ratio was 1.25:1. Most common sites were digital parts of extremities (5/9, 55.56%). Four of these digital locations were subungual (4/5, 80%). The left side (5/9, 55.56%) was the most common laterality. Duration of symptoms till diagnosis was established showed a median of three months [range was one month to nine years]. All nine cases presented with pain. The mean size of glomus lesions was 2.1±1.5 cm). Multiplicity was observed in (2/9, 22.22%) cases. Eight cases were benign (8/9, 88.89%) while one was malignant (1/9, 11.11%). Two out of these eight benign cases were glomangiomatosis. Excision biopsy was the surgical procedure performed in all of our benign cases while the malignant case was treated with amputation of the finger.Diagnosis of glomus tumors requires a high index of clinical suspicion, especially in extra-digital locations. Awareness is essential for early diagnosis and treatment of this lesion, as it is an extremely painful condition and pain is out of proportion to the size of the lesion. Magnetic Resonance Imaging (MRI) is the first investigation of choice for imaging. An early biopsy can confirm the diagnosis of a glomus tumor in time. Complete surgical excision is curative with a low risk of recurrence.

Development and optimization of multivesicular gefitinib liposomal transdermal system employing lipoid S100 for breast cancer: pharmacokinetics, bioavailability, and skin irritation studies in Wistar rats

BackgroundConventional therapies in cancer treatment face challenges including drug resistance, lack of specificity, and severe adverse reactions. This study explores the potential of liposomal transdermal delivery systems as an alternative to current therapies with improved BA and PK. The objective of the study was to formulate gefitinib liposomes by thin film hydration technique (TFH) using lipoid S100. A central composite design (CCD) was used to develop and optimize GEF-LIP-TDDs and to analyze the optimum concentrations of the selected variables (phospholipid, cholesterol) in liposomal formation. The model fitting was performed using Design-Expert (Stat-Ease, Ver 13). The GEF liposomes were evaluated for %EE, mean particle size and PDI. The optimized liposomes were fabricated as a transdermal patch by mercury substrate method and evaluated for %drug content, in vitro diffusion, in vivo biodistribution (PK and BA), and skin irritation studies in female Albino Wistar rats. The stability of the optimized transdermal patch was also assessed for 3 months.ResultsThe CCD model was significant with F-value of 37.97, P-value of 0.0500 and R2 of 0.9644. The average vesicle size, PDI, and ZP of GEF-LIPs (F1–F13) were found to be between 112.8 to 373.7 nm, 0.186 to 0.510 and − 3.69 to − 82.2 mV, respectively. F3-GEF-LIP exhibited a mean vesicle size of 96.07 nm, ZP of − 46.06 mV, and a PDI of 0.423. F3-GEF-LIP demonstrated exceptional %EE (97.79) and sustained release effect (%CDR, 83.32) following a diffusion-controlled mechanism. TEM images confirmed liposomes of multivesicular type (MVV, < 100 nm). Importantly, optimized F3-GEF-LIP-TD showed no signs of edema in Wistar rats. The biodistribution of F3-GEF-LIP-TD was similar to pure GEF and was higher in the liver (p < 0.05). The BA of F3-GEF-LIP-TD was observed to be 74.05 ± 0.11% in comparison with oral GEF-LIP (65.25 ± 0.08%) and pure GEF (58.10 ± 0.17%).ConclusionTFH technique offers stable liposomes with high reproducibility. Our findings imply that GEF-LIP-TD provides enhanced BA and tissue distribution and can be considered as a substitution for orals or in combination for treating breast cancer. Lipoid S100 is a potential lipid for developing stable multivesicular nanoliposomes.Graphical abstract

Partial adrenalectomy by the posterior retroperitoneoscopic approach: A single institution series of 766 consecutive procedures.

Partial adrenalectomy (PA), as an alternative to total adrenalectomy in selected cases, allows for the preservation of adrenocortical function, especially in hereditary and/or bilateral diseases. In this study, we analyze our experience in posterior retroperitoneoscopic PA (PRPA) and its impact on adrenocortical function. From January 2010 to December 2023, 709 PRPAs were performed on 766 adrenal glands in a total of 697 patients (421F; 276M; and mean age 49.3±15.3). Patients suffered from all types of adrenal tumors (239 pheochromocytoma, 225 Conn's syndrome, 102 Cushing's syndrome (CS), 66 nonfunctioning adenomas, 38 adrenal metastases, and 27 others). Mean tumor size was 2.7±1.5cm. Bilateral disease occurred in 135 patients (60 pheochromocytoma, 19 Conn's syndrome, 32 CS, 2 nonfunctioning adenomas, 17 adrenal metastases, and 5 combined diseases). Mean operating time for unilateral operation was 39.2±17.2min. Minor postoperative complications were observed in 1.5% and major complications in 0.1%. The median hospital stay was 2days. In bilateral cases, 18 of 33 (54%) Cushing patients and nine of 102 (9%) non-Cushing patients received corticosteroid replacement therapy (CRT) early postoperatively. Long-term follow-up data were collected for 242 patients (35%). After unilateral surgery, only patients with CS required CRT (8/24). Eleven (24.4%) out of 45 patients with bilateral non-Cushing disease needed CRT. Eight patients (3%) developed ipsilateral recurrent disease. PRPA is a safe procedure with a low complication and recurrence rate. This makes it the preferred operation in cases of bilateral disease and for selected patients with benign pathologies.

The radiological features of HPV-positive vs HPV-negative OPSCC at a South African hospital

Background: Studies have found that, at presentation, human papillomavirus (HPV)-positive oropharyngeal squamous cell carcinoma (OPSCC) has a less advanced primary tumour, more advanced lymph node spread and commonly has cystic metastatic lymph nodes in comparison to HPV-negative OPSCC.Objectives: To compare the radiological features of HPV-positive and HPV-negative OPSCC in South African patients.Method: A retrospective cross-sectional study was conducted at a large South African hospital. Eligibility required a histologically proven OPSCC between 2007 and 2023; a p16 antigen test and, if positive, a confirmatory HPV DNA PCR test and a baseline pre-treatment contrast enhanced neck CT scan. All eligible HPV-positive OPSCC patients and a random sample of eligible HPV-negative OPSCC patients were enrolled.Results: Twenty-one HPV-positive and 55 HPV-negative OPSCC patients were recruited. There was no statistically significant difference in the tumour epicentre location, local advancement (≥ T3 in 67% and 71%, respectively, p = 0.54), mean primary tumour size (41 mm vs. 39 mm, p = 0.73), lymph node spread (bilateral or more in 67% vs. 82%, p = 0.22) or morphologically cystic lymph nodes (10% and 4%, p = 0.61).Conclusion: There was no statistically significant difference in the CT imaging appearances of HPV-positive and HPV-negative OPSCC in the studied sample of South African patients.Contribution: This study documents the radiological features of OPSCC in a small South African sample population, where HPV-positive and HPV-negative OPSCC could not be distinguished on CT criteria and did not display the classic features described in the literature.

Pediatric Cranial Vault Lesions: A Tailored Approach According to Bony Involvement.

Cranial vault lesions are common in children, with dermoid and epidermoid cysts being the most frequent. Management is debated due to their slow growth, but early resection can prevent complications and provide a definitive histological diagnosis, which is sometimes linked to systemic diseases. A retrospective study of children treated surgically for cranial vault tumors from January 2011 to April 2023 was conducted. The data collected included age, gender, symptoms, comorbidities, lesion location, radiological features, surgical techniques, histopathology, and recurrence rates. Eighty-eight children (mean age: 3.5 years, mean tumor size: 1.21 cm) underwent surgery. The most common locations were the frontal and occipital bones. The main diagnoses were dermoid cysts, myofibroma, and Langerhans cell histiocytosis. Gross total resection was achieved in 64 cases with simple skin incisions. In 13 cases, small cranioplasties with bone cement were used. Craniotomy and cranioplasty with autologous bone grafting were performed for 11 patients with lesions larger than 2 cm and full skull thickness erosion. Early resection is recommended for complete removal with minimally invasive surgery and to ensure histological diagnosis. For lesions larger than 2 cm with full skull erosion, cranioplasty with autologous bone is the preferred technique.

Integrating 3D-printed customized guides with hemicorticotomy bone transport: clinical outcomes in chronic osteomyelitis management

PurposeChronic osteomyelitis with large bone defects remains a challenging condition in orthopedic surgery. This study aimed to evaluate the clinical efficacy of hemicorticotomy bone transport assisted by 3D-printed customized guides in the treatment of chronic osteomyelitis with bone defects.MethodsA retrospective analysis was conducted on 21 patients with chronic osteomyelitis treated with hemicorticotomy bone transport with 3D-printed guide assistance between January 2015 and January 2021. Preoperative planning utilized 3D CT reconstruction for precise guide design and osteotomy placement. The surgical technique involved hemicorticotomy, placement of the 3D-printed guide, and gradual bone transport using a monolateral external fixator. Clinical outcomes were assessed using the Association for the Study and Application of Methods of Ilizarov (ASAMI) scoring system. The external fixation time (EFT), external fixation index (EFI), and complications evaluated using the Paley classification were recorded.ResultsThe mean bone defect size was 7.9 ± 2.0 cm. The average follow-up period was 28.6 ± 6.4 months. The mean external fixation time was 289.4 ± 52.7 days, with an external fixation index of 36.8 ± 4.2 days/cm. According to the ASAMI criteria, the bone results were excellent in 17 patients (81%), good in 3 (14%), and fair in 1 (5%). The functional results were excellent in 15 patients (71%), good in 4 (19%), and fair in 2 (10%). Complete eradication of the infection and union at the docking site were achieved in all patients. The complication rate was 38% and all of which were successfully managed.ConclusionHemicorticotomy bone transport assisted by 3D-printed customized guides is an effective treatment for chronic osteomyelitis with bone defects. This technique offers excellent bone healing, favorable functional results, and a relatively low complication rate. Further studies with larger sample sizes are warranted to validate these findings.

Facile Synthesis of Fluorescent Carbon Quantum Dots with High Product Yield Using a Solid-Phase Strategy.

The liquid-phase method is the most commonly utilized strategy for synthesizing fluorescent carbon quantum dots (CQDs). However, the liquid-phase synthesis of CQDs faces challenges such as low yield, complex purification, and the use of toxic solvents, which limit large-scale production and practical applications. In this study, fluorescent CQDs with a high product yield of 78% were synthesized using glucose as a carbon source through a green and facile one-step solid-phase approach, without solvents or post-treatment. A systematic study of the structure and fluorescence properties of the synthesized CQDs was conducted using various characterization techniques. The results indicated that the mean size of obtained CQDs was 4.1 nm, and that their surface had abundant oxygen-containing functional groups, resulting in favorable water solubility. The synthesized CQDs exhibited excitation-dependent fluorescence, with optimal excitation and emission wavelengths at 358 and 455 nm, respectively. Additionally, the CQDs solution showed bright blue fluorescence under 365 nm UV light, with a quantum yield of 6.21% and a fluorescence lifetime of 3.02 ns. This study offers valuable insights into the green and efficient synthesis of fluorescent CQDs powder.