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Despite the significant oxidation resistance of NiCrAlY alloy, one of the disadvantages of this alloy is its softness and poor mechanical properties, and low wear resistance. Therefore, in this study, silicon nitride nanoparticles have been used to improve the hardness and wear resistance of the NiCrAlY alloy. The present research has examined the effect of different amounts of Si3N4 nanoparticles (1, 3, and 5 wt.%) on the structure and mechanical properties of NiCrAlY alloy. The samples were characterised by scanning electron microscopy, X-ray diffraction, and Vickers microhardness device. Initially, Si3N4 powders with 1, 3, and 5 wt% were mixed with NiCrAlY powder in a mechanical mill. Next, the powdered mixtures underwent spark plasma sintering (SPS) operations at 1100 °C for 6 min. The results of microhardness measurements showed that adding 1% Si3N4 to NiCrAlY caused the elevation of the hardness from 418 to 614 HV. Further, the sample indicated a wear rate of 1.42 × 10−5 (m3/N.m) at room temperature, under a loading force of 9.8 N, and a sliding length of 500 m. However, with an increase in the weight percentage of Si3N4 in the sample from 1 to 5 wt%, the hardness diminished from 614 to 543 HV. [ABSTRACT FROM AUTHOR]

Pulmonary alveolar microlithiasis (PAM) is a rare disease with autosomal recessive inheritance. Herein, a 20-year-old lady referred to the hospital with a dry cough for two years. The chest X-ray findings were bilateral reticulonodular opacities in both lungs and honeycomb appearance suspicious for miliary tuberculosis and idiopathic pulmonary fibrosis. A wedge biopsy of lung showed that there were several intraalveolar laminated concretions in the pathology report compatible with pulmonary alveolar microlithiasis and interstitial infiltration of lymphocytes and neutrophils compatible with interstitial pneumonitis. PAM is a rare progressive disease with the production of microliths in pulmonary alveoli. The pathologist, radiologist, and clinician should be familiar with this entity for diagnosis and appropriate management. The family of the patient especially siblings must be evaluated for earlier diagnosis.

Background: Psoriasis is the prime example of psoriasiform tissue pattern and should be differentiated from other psoriasiform dermatoses both clinically and histopathologically. Aim: To evaluate immunohistochemical expression of P53, Ki-67, and CD34 in psoriasis and psoriasiform dermatitis for diagnostic purposes. Methods: An analytical cross-sectional study was performed on the paraffin blocks of 60 psoriasis and 31 psoriasiform dermatitis patients between 2014 and 2017. The selected formalin-fixed paraffin-embedded tissues from each biopsy specimen were cut into 4-micron sections. Initial sections were stained by hematoxylin and eosin staining. Primary antihuman antibodies against P53, Ki-67, and CD34 were applied. Positive control samples for biomarkers were received from former strongly positive samples of papillary endothelial hyperplasia, high grade lymphoma, and breast ductal carcinoma for CD34, Ki-67, and P53, respectively. Results: Out of 60 psoriasis patients, 56.7% were men, with the mean age of 36.8 years. From 31 psoriasiform patients, 45.2% were men, with the mean age of 37.5 years. Both groups were matched in terms of sex and age. The mean staining of three markers was more significant in psoriasiform dermatitis than psoriasis. Conclusion: In spite of some other researches, the present study showed expression of P53, Ki-67, and CD34 biomarkers were significantly higher in psoriasiform dermatitis than psoriasis.

Chromophobe renal cell carcinoma (RCC) is a rare type of kidney neoplasm that is diagnosed in the 6th decade of life with similar incidence in male and female. We reported a case of 73-year-old man with a chief complaint of nocturia, frequency, dribbling and urinary retention with renal mass in ultrasound examination. Histologic examination and immunohistochemistry study revealed the diagnosis of chromophobe RCC which initially was mistaken for oncocytoma in frozen section diagnosis. The pathologist should be aware of this malignant entity and be cautious in diagnosing oncocytoma in frozen section and routine H & E staining.

Background: Amplification of HER2 is an important factor in the diagnosis and treatment of breast cancer. Fluorescence in situ hybridization (FISH) is the gold standard for the detection of HER2-positive tumors. However, the Immunohistochemistry (IHC) assay for the detection of HER2 is more popular in the preclinical laboratory since it is faster and more economical compared to the FISH test. Materials and Methods: In this study, the status of HER2 amplification is determined by the FISH test using 44 formalin-fixed paraffin-embedded tissue samples and comparing the results with the IHC test to determine the reliability of the IHC test. Also, the relationship between HER2 amplification and estrogen, progesterone receptors, P53, age, menopausal status, family history of breast cancer, tumor size, and histological grade were determined. Results: Examination of HER2 in 44 samples by IHC showed 3 (6.8%) and 5 (11.4%) samples were positive (IHC 3+) and negative (IHC 0, 1+), respectively, and 36 (81.8%) samples were ambiguous (IHC 2 +), but examination by FISH showed 21 samples (47, 7%) were positive and 23 samples (52, 3%) were negative. There was a significant difference between IHC and FISH in the detection of HER2 amplification (P=0.019). Also, there was a significant difference between HER2 amplification and menopause in patients (P=0.035). Conclusion: This result demonstrated that the IHC test is not a reliable test to determine HER2 amplification. This study represented that FISH analysis is more reliable than IHC and must be preferentially performed for all cases, especially for HER2 +2 cases for whom the IHC result is 2+. [ABSTRACT FROM AUTHOR]

Objective The purpose of this study was to evaluate the immunohistochemical expression of Ki-67 marker in Mycosis Fungoides (MF) and Lichen Planus (LP) lesions. Methods This cross-sectional analytical study included patients undergoing skin biopsy with their first clinical and pathologic diagnosis of MF and cutaneous LP by Ki-67 immunohistochemistry (IHC). Sixty-two patients with cutaneous LP and MF were studied in two groups of 39 and 23 patients, respectively. Linear regression was used for the possible correlation between age and Ki-67 index (%) in both LP and MF patients. Results The results of this study found that Ki-67 was expressed in 100% of both MF and LP lesions, and no significant correlation was found between Ki-67 and either of the two types of diseases (p=0.606). The results of this study also showed that expression of Ki-67 marker was more than 25% in both types of diseases in 70% of the population, which seems not to be directly related to malignancy. Conclusion IHC with proliferative marker Ki-67 is not a valuable technique for differentiating cutaneous LP from MF lesions alone. [ABSTRACT FROM AUTHOR]

Tuberous sclerosis complex (TSC) is a rare genetic disease that is inherited autosomal dominantly and may be associated with subependymal giant cell astrocytoma (SEGA) in 10-20% of cases. Different phenotypes are related to the form of lesions in different parts of the body, including skin, brain, kidneys, lungs, and heart. The age of the patient, the location of the tumor, and associated skin or neurological lesions may guide the pathologist for a definite diagnosis. Here we report a case of SEGA in an adolescent with TSC. Neurological clues including seizure and mental retardation, facial angiofibroma, renal mass, and histopathology examination of the brain tumor culminated in the diagnosis of TSC and SEGA. [ABSTRACT FROM AUTHOR]