Diffuse Type Research Articles

Fine-needle aspiration cytology of diffuse type tenosynovial giant cell tumor with malignant trasformation and review of literature.

Tenosynovial giant cell tumors (TGCTs) arise from the synovium of joint, bursa, and tendon sheath. Diffuse type often affects large joints, has higher recurrence rates, metastases, and malignant transformation potential compared to the localized type. The cytopathology of TGCT, a fibrohistiocytic neoplasm distinct from other giant cell-rich soft tissue tumors, is rarely reported. Here we describe cytomorphology of a case of TGCT that was initially diagnosed on fine-needle aspiration cytology (FNAC) consisting of a mixture of singly scattered polygonal or spindle mononuclear cells with hemosiderin laden macrophages, inflammatory cells, and a population of multinucleated osteoclast-like giant cells. Persistent symptoms and repeat excision were consistent with high-grade malignant transformation of the TGCT. Atypical cytologic features in a recurrent, infiltrative, or a metastatic lesion should raise suspicion for malignancy.

Long-Term Outcomes of Individualized Repair in Patients with Supravalvular Aortic Stenosis.

Various surgical techniques have been introduced to treat supravalvular aortic stenosis (SVAS). However, there is no consensus on the optimal approach. This study aimed to analyze the outcomes of surgical treatment of SVAS and determine the optimal strategy. The Kaplan-Meier curve was used to demonstrate the survival estimates. The Cox proportional hazard model was used to identify risk factors for residual aortic stenosis and residual stenosis-related reintervention. From December 2008 to December 2023, 98 patients with SVAS undergoing surgical repair in our institution were included [McGoon group, n = 62; Doty group, n = 36]. There were 2 in-hospital deaths and 1 late death. The survival rates at 1, 5, and 15years were 98.0%, 96.7%, and 96.7%, respectively in the whole cohort. Residual aortic stenosis occurred in 18 patients. Multivariable analysis showed that preoperative gradient ≥ 90mmHg (P = 0.002) and Williams syndrome (P = 0.002) were incremental risk factors for residual aortic stenosis, but surgical technique (P = 0.579) was not a risk factor for residual aortic stenosis. In the McGoon group, patients with diffuse type had worse freedom from residual aortic stenosis than patients with discrete type (P = 0.007). However, in the Doty group, patients with diffuse type had comparable freedom from residual aortic stenosis to patients with discrete type (P = 0.911). Residual stenosis-related reintervention occurred in 15 patients. Fifteen patients all underwent residual aortic stenosis-related reintervention. Of 15 patients, 6 patients also underwent residual pulmonary stenosis-related reintervention. On multivariate analysis, Williams syndrome (P < 0.001), preoperative sinotubular junction (STJ) z-score < - 3.5 (P = 0.051), and Doty repair (P = 0.033) were found to be independent risk factors associated with residual stenosis-related reintervention. In the whole cohort, freedom from residual stenosis-related reintervention at 1, 5, and 15years were 97.8%, 89.3% and 76.1%, respectively. Surgical repair of SVAS can be safely achieved using different techniques, with similar long-term mortality. Compared with McGoon repair, Doty repair was significantly associated with decreased residual aortic stenosis rates in patients with diffuse-type SVAS. Patients with preoperative gradient ≥ 90mmHg or Williams syndrome are more prone to residual aortic stenosis. Surgical technique was not associated with residual aortic stenosis rates. Williams syndrome, preoperative STJ z-score < - 3.5, and Doty repair are associated with higher residual stenosis-related reintervention rates.

Mathematical Models for Estimating Diffusion Coefficients in Concentrated Polymer Solutions from Experimental Data

Diffusion processes in operations involving polymeric materials are of significant interest. Determining experimental values for diffusion coefficients is often challenging. Estimating these coefficients in concentrated polymer solution, polymer films, and membranes relies on experimental tests where the polymer is brought into contact with certain components/solvents. The diffusion coefficient values depend on the diffusion type, which is affected mainly by the nature of the polymer, concentration, and temperature. The literature presents an extensive amount of information regarding the diffusion phenomenon. This paper makes a particular contribution by showing how experimental data obtained from different applications can be processed to determine diffusion coefficients. The manuscript addresses some aspects regarding solvent diffusion in polymers, and illustrates how to determine the diffusion coefficients from experimental data. For specific cases of diffusion, several models for the predictive estimation of diffusion coefficients are also presented. Polymer–solvent systems such as polyvinyl alcohol (PVA)–water, cellulose acetate (CA)–tetrahydrofuran (THF) and cellulose triacetate (CTA)–dichloromethane (DCM) are investigated, with their diffusion mechanisms influenced by changes in structure caused by variations in concentration and temperature. The experimental data obtained through a gravitational technique allow for the highlighting of the diffusion mechanism and the selection of an appropriate mathematical model. A change in the structure of the polymer during the experiment leads to diffusion anomalies. Modeling the experimental data yielded diffusion coefficient values that vary based on the type of system investigated, composition and temperature. Thus, in the case of the CTA-DCM system, the diffusion coefficient at 303 K, at various concentration values, is in the range of 4.5 and 8·10−11 m2/s; for the PVA-H2O system, D = 4.1·10−12 m2/s at 303 K, and D = 6.5·10−12 m2/s at 333 K; while for the CA-THF system, the solvent–polymer diffusion coefficient has a value of 2.5∙10−12 m2/s at 303 K, and D = 1.75∙10−11 m2/s at 323 K. Mathematical models can be useful in studies regarding the drying of polymer films with complex structures, providing knowledge for designing or selecting suitable equipment.

Singularly perturbed elliptic problems of convection–diffusion type with non-smooth inflow/outflow boundary conditions

A singularly perturbed elliptic problem, with non-smooth inflow or non-smooth outflow boundary conditions, is examined. A decomposition of the continuous solution is constructed, whose components identify the various types of layer functions that can exist in the solution. Parameter-explicit pointwise bounds on the first three partial derivatives of these components are established. An appropriate Shishkin mesh is identified for the problem and this is combined with upwinding to form a numerical method. Parameter-uniform error bounds are deduced. Numerical results are presented to illustrate the performance of the numerical method.

HGG-09. CONTRASTING CLINICAL COURSES OF THREE PEDIATRIC PATIENTS WITH PDGFRA AMPLIFIED RADIATION-INDUCED HIGH-GRADE GLIOMA

Abstract BACKGROUND Radiation-induced gliomas (RIG) can occur in 3% of patients receiving cranial radiation. Often, these gliomas are high-grade, treatment refractory, and share common molecular profiles like PDGFRA amplification, regardless of their previous malignant origin. Despite similar genetic alterations, the clinical course of these tumors is varied and not well-studied. Herein, we describe three patients with a PDGRFA-amplified RIG with a particular focus on their contrasting disease course. CASE DESCRIPTION: Our first patient is a now-deceased male diagnosed with medulloblastoma at 5 years of age, treated with surgical resection and craniospinal radiation followed by chemotherapy per COG ACNS0332. Ten years later, he was diagnosed with diffuse pediatric type high-grade-glioma (HGG) in the pons with PDGFA, KIT, MTAP amplification, and CDKN2A/B loss. His condition deteriorated quickly, and he succumbed to his disease in 8 weeks after family decided against further therapies. Our second patient is a now 20-year-old female, initially diagnosed with a craniopharyngioma at 6 years of age and treated with surgical resection and adjuvant radiation therapy. Eleven years later, she developed a diffuse pediatric type HGG in the pons with PDGFRA, MDM2, and MYCN amplification. She was treated with radiation therapy and has had stable disease on serial imaging for 3 years. Our third patient is a now-deceased male diagnosed with a right temporal melanotic neuroectodermal tumor at 5 years of age, treated with surgical resection and craniospinal radiation followed by chemotherapy per POG99701. Fifteen years later, he developed a diffuse pediatric-type HGG in the cerebellum/pons with PDGRFA amplification. He was treated with proton radiation and concurrent oral Temozolomide per COG ACNS0423. His disease progressed on treatment, and he died prior to initiation of a PDGFRA kinase inhibitor (avapritinib). CONCLUSIONS Further investigation into the underlying factors that drive the differing disease course in patients with RIG is needed.

METB-15. ROLE OF DNA METHYLATION PROFILING IN THE MANAGEMENT OF PEDIATRIC CENTRAL NERVOUS SYSTEM TUMORS: A SINGLE INSTITUTIONAL SERIES

Abstract BACKGROUND DNA methylation profiling has now been integrated into the WHO classification of CNS tumors and serves as confirmatory means to diagnose CNS tumors in conjunction with genetic sequencing/microarray analysis. The practical impact on patient care in the retrospective and prospective settings is less known. METHODS Methylation analysis was performed on a cohort of previously and newly diagnosed children with CNS tumors at Children’s Hospital Orange County from 2022-2023. Data regarding histologic diagnosis, integrated molecular diagnosis, methylation classification, timing of result completion and functional impact of methylation results on patient diagnosis/management was evaluated. RESULTS Forty patients (21 boys, ages 5 weeks-17 years) with previously diagnosed (N=11) or newly diagnosed (N=21) CNS tumors were evaluated by methylation analysis at one or more institutions. The most common tumor types were diffuse type pediatric high-grade glioma (N=6) and ependymoma PFA (n=4). Methylation analysis revealed no match in two cases (ALK-EML4 fusion embryonal tumor and recurrent low grade glioneuronal tumor) and had insufficient DNA extraction in one patient with low grade glioneuronal spinal cord tumor. Among the 5 tumors with duplicate methylation analyses at two institutions, three Ependymoma PFA subgroups were concordant while two showed differing classifications (diffuse type pediatric high-grade glioma RTK1 subtype vs. non- classifiable and medulloblastoma group 4 vs. non-WNT, non-SHH). In patients with previously diagnosed CNS tumors, methylation either led to a change in classification or modification of diagnosis in 7 out of 11 patients. The average time from surgery to the receipt of methylation results for newly diagnosed patients was 24 days (range 4-90 days). CONCLUSION Methylation analysis was beneficial in both the previously diagnosed and newly diagnosed setting in patients with previously difficult to classify tumors following conventional molecular analysis. Changes in tumor classification or modifications in diagnosis were observed in the majority of patients.

Early gastric cancer of young patients treated by endoscopic submucosal dissection: focusing on the different characteristics and prognosis of elderly patients.

A small portion of patients are diagnosed with early gastric cancer (EGC) and undergo endoscopic submucosal dissection (ESD) at a young age. However, their clinical outcomes are rarely known. We investigated to identify the feasibility and clinical outcomes of ESD for EGC focusing on young patients. We analyzed the clinical characteristics and outscomes of patients who had undergone ESD for the treatment of EGC at < 50years of age. We enrolled patients who had been diagnosed with EGC and had undergone ESD between 2006 and 2020. We divided them by age as follows: ≤ 50 and > 50years into the young age (YA) and other age (OA) groups, respectively. Altogether, 1681 patients underwent ESD for EGC (YA group: 124 [7.4%], OA group: 1557 [92.6%]). The YA group had less severe atrophy and more undifferentiated (37.1% vs. 13.9%, P < 0.001) and diffuse type (25% vs. 7.7%, P < 0.001) histology. The curative resection rate was not significantly different between the groups. However, among 1075 patients who had achieved curative resection and had been followed-up for > 12months, the YA group had a lower incidence of MGN (5.2% vs. 17.5%, P = 0.004) and MGC (2.6% vs. 10.9%, P = 0.019) than those exhibited by the OA group. The YA group was a significant negative predictor of MGN (odds ratio [OR]: 2.983, 95% confidence interval [CI] 1.060-8.393, P = 0.038), and marginally negative predictor in MGC (OR: 3.909, 95% CI: 0.939-16.281, P = 0.061). ESD is a favorable and effective therapeutic modality for EGC patients aged < 50years, once curative resection is achieved.

Response Behavior of Inverse Diffusion Flame to Low Frequency Acoustic Field

ABSTRACT Conducting the investigation of flame dynamics perturbed by acoustic waves had guiding significance for flame extinguishing technology. In this paper, the behavior of inverse diffusion flame under the influence of 200–300 Hz sound waves was reported for the first time. Detailed analysis of the entire process of flame from steady state to extinction, including flame structure, periodic characteristics, temperature and KL factor distribution. The relationship between flame morphology parameters and acoustic parameters was established through dimensionless analysis. In addition, the flame extinguishing performance of sound waves in this frequency band was measured and analyzed. The results indicated that the flame could still maintain the typical inverse diffusion flame shape under low sound pressure, and the pulsation frequency was stable. However, when the sound pressure rose to a certain level, the flame began to pulsation in a disorderly manner. In addition, with the increase of sound pressure, the flame morphology would undergo significant changes, and the temperature and KL factor showed a trend of first increasing and then decreasing. The mechanism of sound wave suppression of flames was related to the unsteady flow generated by sound waves. Through dimensionless analysis, it was found that the intensity of this disturbance was directly proportional to the arithmetic square root of sound pressure and inversely proportional to frequency.

Hybrid films loaded with 5-fluorouracil and Reglan for synergistic treatment of colon cancer via asynchronous dual-drug delivery

Combination therapy with oral administration of several active ingredients is a popular clinical treatment for cancer. However, the traditional method has poor convenience, less safety, and low efficiency for patients. The combination of traditional pharmaceutical techniques and advanced material conversion methods can provide new solutions to this issue. In this research, a new kind of hybrid film was created via coaxial electrospraying, followed by a casting process. The films were composed of Reglan and 5-fluorouracil (5-FU)-loaded cellulose acetate (CA) core-shell particles in a polyvinylpyrrolidone (PVP) film matrix. Microscopic observations of these films demonstrated a solid cross section loaded with core-shell particles. X-ray diffraction and Fourier-transform infrared tests verified that the Reglan and 5-FU loaded in the films showed amorphous states and fine compatibilities with the polymeric matrices, i.e., PVP and CA, respectively. In vitro dissolution tests indicated that the films were able to provide the desired asynchronous dual-drug delivery, fast release of Reglan, and sustained release of 5-FU. The controlled release mechanisms were shown to be an erosion mechanism for Reglan and a typical Fickian diffusion mechanism for 5-FU. The protocols reported herein pioneer a new approach for fabricating biomaterials loaded with multiple drugs, each with its own controlled release behavior, for synergistic cancer treatment.

Counting jumps: does the counting process count?

In this paper, we develop a ‘jump diffusion type’ financial model based on renewal processes for the discontinuous part of the risk driver, and study its ability to price options and accurately reproduce the corresponding implied volatility surfaces. In this model, the log-returns process displays finite mean and variance, and non-vanishing skewness and excess kurtosis over a long period. The proposed construction is parsimonious, and it allows for a simple and intuitive pricing formula for European vanilla options; furthermore, it offers an efficient Monte Carlo sample path generator for the pricing of exotic options. We illustrate the performance of the proposed framework using observed market data, and we study the features of the best fitting model specifications.

A computational approach for 2D elliptic singularly perturbed weakly coupled systems of convection–diffusion type with multiple scales and parameters in the diffusion and the convection terms

In this work, we consider the efficient resolution of a 2D elliptic singularly perturbed weakly coupled system of convection–diffusion type, which has small parameters at both the diffusion and the convection terms. We assume that the diffusion parameters can be distinct at each equation of the system, and also, they can have different orders of magnitude, but the convection parameter is the same at both equations of the system. Then, in general, overlapping regular or parabolic boundary layers can appear in the exact solution. The continuous problem is approximated by using the standard upwind finite difference scheme, which is constructed on a special piecewise uniform Shishkin mesh. Then, the numerical scheme is an almost first‐order uniformly convergent method with respect to all the perturbation parameters. Some numerical results, obtained with the numerical algorithm for one test problem, are presented, which show the good performance of the proposed numerical method and also corroborate in practice the theoretical results.

Clinical outcomes and biomarker exploration of first-line PD-1 inhibitors plus chemotherapy in patients with low PD-L1-expressing of gastric or gastroesophageal junction adenocarcinoma

BackgroundThe beneficial effects of first-line programmed death-1 (PD-1) inhibitors plus chemotherapy in patients with low programmed death-ligand 1 (PD-L1)-expressing advanced gastric or gastroesophageal junction (G/GEJ) adenocarcinoma are controversial.MethodsWe conducted a retrospective analysis of patients with G/GEJ adenocarcinoma who had undergone first-line treatment with PD-1 inhibitors plus chemotherapy between October 2017 and May 2022. The primary outcomes were objective response rate (ORR) and progression-free survival (PFS). SPSS software V27.0 was used for data analysis.ResultsOf 345 enrolled patients, 290 had measurable lesions. The overall ORR was 59.3%. PD-L1 status was available in 171 patients, and 67.8% of them were considered as low PD-L1 expression level (combined positive score (CPS) < 5). Patients with PD-L1 CPS < 5 showed a lower response rate (51.1% vs 70.8%, P = 0.024) and a worse PFS (P = 0.009) compared to those with PD-L1 CPS ≥ 5. In the PD-L1 low-expression cohort, patients with non-diffuse type, GEJ cancer, synchronous metastasis, distant lymph node metastasis, liver metastasis, non-peritoneal metastasis, and HER2 positive were significantly associated with higher response rates to PD-1 inhibitors plus chemotherapy (P < 0.05). The presence of peritoneal metastasis (P = 0.028) and diffuse type (P = 0.046) were identified as independent predictors of poor PFS in multivariate analysis of the PD-L1 CPS < 5 subgroup. When evaluated for correlation with overall survival (OS) in the PD-L1 low-expression subgroup, peritoneal metastasis was found to be the only independent prognostic factor of an increased risk of death (hazard ratio: 2.31, 95% CI 1.09–4.90; P = 0.029).ConclusionsPD-L1 CPS ≥ 5 is significantly associated with improved response and extended PFS in G/GEJ cancer patients treated with a combination of PD-1 inhibitors and chemotherapy. Specific subgroups within the low PD-L1-expressing population, such as those with non-diffuse-type tumors and without peritoneal metastases, may also benefit from immunotherapy combined with chemotherapy.

Redefining aberrant P53 expression of gastric cancer and its distinct clinical significance among molecular-histologic subtypes

BackgroundNumerous studies have demonstrated a correlation between p53 overexpression and diminished survival in gastric cancer patients. However, conflicting findings exist, and we hypothesize that these discrepancies arise from the cancer's complexity and heterogeneity, coupled with a lack of consensus on aberrant p53 expression. MethodsWe enrolled a cohort of 187 patients with surgically resected gastric cancer. Patient categorization was based on Epstein–Barr virus (EBV), microsatellite instability (MSI), and Lauren classification (intestinal, diffuse and mixed). Utilizing an incremental algorithm, we evaluated p53 immunohistochemical (IHC) patterns in all 187 cases, while next-generation sequencing was successfully performed on 152 cases to identify TP53 mutations (mutTP53). ResultsMutTP53 was identified in 32 % of the 152 cases, comprising 36 missense, 5 nonsense, and 7 frameshift alterations. Missense mutations predominantly correlated with p53 overexpression, while nonsense and frameshifting alterations related to null expression. Trial calculations indicated that null expression and a p53 IHC cutoff at >40 % offered the best prediction of mutTP53 (kappa coefficient, 0.427), with the highest agreement (0.524) observed in diffuse type and the lowest (0.269) in intestinal type. Null expression and a p53 IHC cutoff at >10 %, but not mutTP53 per se, provided the optimal prediction of survival outcome (p = 0.043), particularly in diffuse type (p = 0.044). Multivariate analysis showed that aberrant p53 IHC expression was not an independent prognostic factor. ConclusionsP53 IHC patterns are predictive biomarkers for mutTP53 and gastric cancer outcomes, where a prerequisite involves a nuanced approach considering cutoff values and molecular-histologic subtyping.

Spatiotemporal characteristics of flow in the bend and return channel perturbed by rotor–stator interaction

The flows in turbomachinery systems are strongly perturbed by the rotor–stator interaction (RSI) between the rotating and stationary through-flow components, generating the fluctuating flows. This work presents a numerical investigation of a flow in a test centrifugal pump system consisting of an impeller, diffuser, bend, and return channel at the designed and low flow rates. Both vaneless and vaned diffuser models are considered to determine the perturbation of the diffuser vanes on the flow. The objective is to quantitatively assess the impacts of two influential factors, i.e., the diffuser type and the flow rate, on the spatiotemporal characteristics of the transient flow in the various through-flow components. Particular attention is paid to the generation of the reversed flow, circulating vortices, and temporal fluctuations of the velocity field. It is found from the numerical data that both the flow rate and the diffuser type affect the temporal fluctuations of the flow, primarily via the impact of the RSI-induced large-scale vortices generated in the passages of the impeller and the vaned diffuser. The flow in the bend experiences the streamline curvature on the solid walls; thus, the peak values of the fluctuating amplitude of the streamwise and transverse velocities and the reversed flow may shift between the two halves of the channel close to the inner and outer wall. The boundary layer flow patterns are mainly determined by the flow rate at the low flow rate and by the diffuser vanes at the designed flow rate. This work comprehensively reveals the transient behaviors and unsteadiness of the flow which was not provided in the experimental investigation for the test centrifugal pump system which was widely studied since the essential flow physics are included. The numerical data in the stationary bend and return channel are first provided, which are of engineering significance for this type of centrifugal turbomachinery.

On the BEM solution of convection–diffusion type equations involving variable convective coefficients

In this study, numerical solutions of the unsteady convection–diffusion type equations of variable convective coefficients are investigated by two effective techniques alternative to direct boundary element method (BEM). That is, the domain boundary element and the dual reciprocity BEMs with the fundamental solution of convection–diffusion equation are used in space to transform the governing differential equations into equivalent integral equations while a backward finite difference scheme is utilized in time discretization. The fruitfulness of these combined techniques are shown by the implementation of the techniques for some widely investigated fluid dynamics problems. In fact, the lid-driven cavity flow is solved, and precise results are attained as benchmarks for assessing the accuracy of the aforementioned methods. Further, the application of the methods is extended for the natural convection flow which is governed mainly by the convection–diffusion type equations accompanied by the velocity components as variable convective coefficients. The obtained numerical results reveal that the domain BEM which uses the fundamental solution of convection–diffusion equation captures the characteristics and physical advancement of the fluid flow quite well at various combined values of the problem physical parameters.

Prevalence of pathogenic genetic variants in patients with gastric cancer ascertained through multi-gene panel testing.

10578 Background: Gastric cancer (GC) is the fourth leading cause of cancer-related deaths worldwide. The role of pathogenic/likely pathogenic variants (PVs) in cancer predisposition genes is not well understood. We aimed to assess the prevalence of PVs in GC patients undergoing germline genetic testing (GGT) via multi-gene panel testing (MGPT) at a large commercial laboratory. Methods: Retrospective review of MGPT (&gt;10 genes) in GC patients at a large commercial laboratory (Invitae Corp.) from March 2015 to July 2023 was performed. GC included diffuse type, intestinal type or unspecified type, as provided by ordering clinicians. Association of patient characteristics with positive GGT results was assessed with logistic regression with a significance threshold of p &lt; 0.05. Results: 3,706 GC patients underwent GGT(Table). Overall, 495 (13.4%) patients were found to carry ≥1 PV, including 29 patients with 2 PVs and 3 patients with 3 PVs. GGT was negative in 1,890 (51.0%) patients, 1,199 (32.4%) had a variant of uncertain significance-only and 121 (3.3%) carried a single PV in a gene associated with autosomal recessive inheritance. PVs were identified in 38 genes; 77.7% (385/495) were in a gene previously associated with GC, primarily the homologous recombination repair genes ( BRCA1, BRCA2, PALB2and ATM, 34.9%), the Hereditary Diffuse Gastric Cancer genes ( CDH1and CTNNA1, 19.6%) and mismatch repair genes ( MLH1, MSH2, MSH6, PMS2and EPCAM, 17.4%). Males were more likely to carry a PV than females (OR 1.4, 95% CI 1.1-1.7) and having a personal history of another cancer increased the odds of carrying a PV (OR 1.3, 95% CI 1.0-1.7). Age, number of genes tested and histology were not significantly associated with PV. Conclusions: In this large study of GGT in GC patients, the prevalence of PVs in cancer associated genes was 13.4%, higher than previous estimates of 3-5%. PVs were predominantly in genes associated with GC. Male sex and history of other cancers were associated with a PV. Limitations include incomplete histologic data, varying panel size, and ascertainment bias as patients may have had additional personal/family history that prompted GGT. These results support consideration of GGT in all GC patients as prevalence of PVs is similar to other cancer types for which guidelines recommend universal genetic testing.[Table: see text]

BORIDE LAYER GROWTH KINETICS ON X90CrMoV-18 STEEL

Boronizing is a type of thermal diffusion with the primary goal of increasing the surface hardness, wear and corrosion resistance. The wear resistance of boronized parts depends on the type of borides that form on the steel surface and their thickness. This study investigated the properties of boride layers formed on X90CrMoV-18 martensitic stainless steel, using pack boronizing carried out in a temperature range of 850–1000 °C and in durations of (1, 3 and 5) h. Results indicate a difference in the boride layer thickness of 3–80 µm and volume share of boride phases depending on the temperature and time of boriding. From the boriding compound depth, values of the frequency factor and activation energy were determined using the Arrhenius equation. With these values, the parabolic equation for predicting the growth rate of a boride layer was formulated and validated for different times and temperatures of boriding.

Tracing the Connection of Iron and Copper in Chronic Telogen Effluvium

Chronic Telogen Effluvium (CTE) is a common non- scarring, diffuse type of hair loss, affecting a significant proportion of population. The purpose of the current study is to assess the relationship between CTE and trace metal levels, specifically copper and iron. Objective: To collect hair and serum samples from both control group and patients with CTE and to analyze the association between hair copper and iron content and serum copper and iron levels in both groups. Methods: The Dow University Hospital (DUHS) in Karachi, Sindh, Pakistan, served as the site of this case control research. The duration of study was one year. The study population encompassed hundred individuals, categorized into 50 cases with CTE and 50 healthy controls. Using non probability sampling technique (convenient sampling), the sample size was determined. Diagnostic criteria a positive hair pull test. Hair and serum samples were collected from both groups for trace metal analysis. Analysis was carried out using ab Atomic Absorption Spectrophotometer (Perkin Elmer Analyst 800, located in Waltham, MA, USA). Data analysis was carried out using SPSS® software for Windows® version 16.0. Results: Results showed that hair samples from patients had considerably lower iron levels than those from controls (p&lt;0.001), while there was no significant difference in copper levels (p=0.713). Additionally, the CTE group showed noticeably greater copper levels (p&lt;0.001) and significantly lower serum iron levels (p&lt;0.001). Conclusions: The study identified a positive association between iron deficiency and hair loss.

Risk Factors and Biomarkers for Interstitial Lung Disease and Pulmonary Arterial Hypertension in Systemic Sclerosis: Experience of Two Tertiary Centers in Turkey

Purpose: To define the clinical and laboratory characteristics of patients with systemic sclerosis (SSc), and to investigate the risk factors affecting the prevalence of interstitial lung disease (ILD) and pulmonary arterial hypertension (PAH), which are important causes of morbidity and mortality. Patients and methods: 88 patients with SSc were compared according to the presence of ILD and PAH. ILD was confirmed by chest computed tomography, and PAH was suspected and considered probable PAH when right ventricular systolic pressure was &gt;40 mmHg according to echocardiography. Results: Of the 88 patients, 44.3% had diffuse-type and 55.7% had limited-type SSc. Diffuse type, percentages of positive anti-scleroderma-70 (anti-Scl70) antibody and anti-centromere antibody, white blood cell (WBC), platelet, erythrocyte sedimentation rate (ESR), smoking, and presence of the sclerodactyly and telangiectasia differed significantly in SSc with ILD group. The positive titer of anti-Scl70 antibody (odds ratio (OR)=6.124, p=0.004), platelet count (OR=0.138, p=0.002), ESR (OR=1.042, p=0.035) and presence of telangiectasia (OR=10.571, p=0.001) were associated with ILD in patients with SSc. Also, while diffuse-type (OR=0.223, p=0.010), the presence of sclerodactyly (OR=11.112, p=0.028) and telangiectasia (OR=3.861, p=0.020) were risk factors for the development of ILD in nonspecific interstitial pneumonia pattern, anti-Scl-70 antibody positivity (OR=12.921, p=0.019) and high ESR (OR=1.034, p=0.030) were found to be risk factors for the development of usual interstitial pneumonia pattern. Conclusion: Positive titer of the anti-Scl70 antibody, diffuse type, presence of telangiectasia, and high ESR were independently associated with ILD in SSc patients.

Fungal Melanonychia: A Systematic Review.

Fungal melanonychia is an uncommon condition, most typically caused by opportunistic melanin-producing pigmented filamentous fungi in the nail plate. In the present study, the clinical characteristics of patients diagnosed with fungal melanonychia were analyzed through a systematic review of cases reported in the literature. The MESH terms used for the search were "melanonychia" AND "fungal" OR "fungi" through four databases: PubMed, SciELO, Google scholar and SCOPUS. After discarding inadequate articles using the exclusion criteria, 33 articles with 133 cases were analyzed, of which 44% were women, 56% were men and the age range was between 9 and 87 years. The majority of cases were reported in Turkey followed by Korea and Italy. Frequent causal agents detected were Trichophyton rubrum as non-dematiaceous in 55% and Neoscytalidium dimidiatum as dematiaceous in 8%. Predisposing factors included nail trauma, migration history, employment and/or outdoor activities. Involvement in a single nail was presented in 45% of the cases, while more than one affected nail was identified in 21%, with a range of 2 to 10 nails. Regarding the clinical classification, 41% evidenced more than one type of melanonychia, 21% corresponded to the longitudinal pattern and 13% was of total diffuse type. Likewise, the usual dermoscopic pattern was multicolor pigmentation. It is concluded that fungal melanonychia is an uncommon variant of onychomycosis and the differential diagnosis is broad, which highlights the complexity of this disease.