Sildenafil improves radiation-induced oral mucositis by attenuating oxidative stress, NF-κB, ERK and JNK signalling pathways

Radiation-induced oral mucositis is a common and dose-limiting complication of head and neck radiotherapy with no effective treatment. Previous studies revealed that sildenafil, a phosphodiesterase 5 inhibitor, has anti-inflammatory and anti-cancer effects. In this study, we investigated the effect of sildenafil on radiation-induced mucositis in rats. Two doses of radiation (8 and 26 Gy X-ray) were used to induce low-grade and high-grade oral mucositis, separately. A control group and three groups of sildenafil citrate-treated rats (5, 10, and 40 mg/kg/day) were used for each dose of radiation. Radiation increased MDA and activated NF-κB, ERK and JNK signalling pathways. Sildenafil significantly decreased MDA level, nitric oxide (NO) level, IL1β, IL6 and TNF-α. The most effective dose of sildenafil was 40 mg/kg/day in this study. Sildenafil also significantly inhibited NF-κB, ERK and JNK signalling pathways and increased bcl2/bax ratio. In addition, high-dose radiation severely destructed the mucosal layer in histopathology and led to mucosal cell apoptosis in the TUNEL assay. Sildenafil significantly improved mucosal structure and decreased inflammatory cell infiltration after exposure to high-dose radiation and reduced apoptosis in the TUNEL assay. These findings show that sildenafil can improve radiation-induced oral mucositis and decrease the apoptosis of mucosal cells via attenuation of inflammation and oxidative stress.

Whole-organ decellularization of the human uterus and in vivo application of the bio-scaffolds in animal models

PURPOSE

The aim of this investigation was to design a perfusion-based decellularization protocol to provide whole human uterine bio-scaffolds with preserved structural and componential characteristics and to investigate the in vivo properties of the decellularized tissues.

METHODS

Eight human uteri, donated by brain-dead patients, were decellularized by perfusion of sodium dodecyl sulfate (SDS) through the uterine arteries using a peristaltic pump. The bio-scaffolds were evaluated and compared with native human uterus regarding histological, immunohistochemical, structural, and bio-mechanical properties, in addition to CT angiographies to examine the preservation of the vascular networks. Subsequently, we obtained acellular patches and implanted them on uterine defects of female Wistar rats to investigate the bio-compatibility and regenerative potential of the bio-scaffolds. Finally, we performed immunostaining to investigate the potential role of circulating stem cells in recellularization of the implanted bio-scaffolds.

RESULTS

The outcomes of this investigation confirmed the efficacy of the proposed protocol to provide whole human uterine scaffolds with characteristics and extra-cellular matrix components similar to the native human uterus. Subsequent in vivo studies demonstrated the bio-compatibility and the regenerative potential of the scaffolds and suggested a signaling pathway as an underlying mechanism for the regenerative process.

CONCLUSIONS

To the best of our knowledge, this investigation provides the first efficient perfusion-based decellularization protocol for the human uterus to obtain whole-organ scaffolds. The outcomes of this investigation could be employed in future human uterus tissue engineering studies which could ultimately result in the development of novel treatments for female infertile patients.

microRNAs and long non-coding RNAs as biomarkers for polycystic ovary syndrome

Polycystic ovary syndrome (PCOS) is known as the most common metabolic/endocrine disorder among women of reproductive age. Its complicated causality assessment and diagnostic emphasized the role of non‐coding regulatory RNAs as molecular biomarkers in studying, diagnosing and even as therapeutics of PCOS. This review discusses a comparative summary of research into microRNAs (miRNAs) and long non‐coding RNAs (lncRNAs) that are molecularly or statistically related to PCOS. We categorize the literature in terms of centering on either miRNAs or lncRNAs and discuss the combinatory studies and promising ideas as well. Additionally, we compare the pros and cons of the prominent research methodologies used for each of the abovementioned research themes and discuss how errors can be stopped from propagation by selecting correct methodologies for future research. Finally, it can be concluded that research into miRNAs and lncRNAs has the potential for identifying functional networks of regulation with multiple mRNAs (and hence, functional proteins). This new understanding may eventually afford clinicians to control the molecular course of the pathogenesis better. With further research, RNA (with statistical significance and present in the blood) may be used as biomarkers for the disease, and more possibilities for RNA therapy agents can be identified.

Involvement of Cannabinoid Type 2 Receptors in the Favorable Effects of Sumatriptan on the Random-Pattern Skin Flap Survival in Rats: A Novel Potential Target

INTRODUCTION

Recent investigations have indicated the potential therapeutic role of cannabinoid type 2 (CB2) receptors in various inflammatory-related disorders. However, the role of these receptors has not been studied in skin flap models to date. In this study, we aimed to evaluate the possible involvement of CB2 receptors in the anti-inflammatory effects of sumatriptan, improving the random-pattern skin flap survival in rats.

METHODS

In a controlled experimental study, 36 male Wistar rats were randomly divided into 6 study groups (n = 6 per group). Two doses of sumatriptan (0.1 and 0.3 mg/kg) were administered intraperitoneally 30 min before harvesting the flap tissue. In a separate group, SR144528 (a selective CB2 receptor inverse agonist) was injected before the most effective dose of sumatriptan to determine the possible involvement of CB2 receptors in its action. Histopathological examinations, the expression level of CB2 receptors (Western blot analysis), and IL-1β and TNF-α concentrations (ELISA) were explored in the skin flap sampled tissues.

RESULTS

Sumatriptan 0.3 mg/kg remarkably enhanced the skin flap survival in all macroscopic and microscopic investigations compared to the control group (p < 0.001). IL-1β and TNF-α levels were significantly attenuated (p < 0.001), and the expression of CB2 receptors in skin cells was amplified in rats treated with sumatriptan 0.3 mg/kg (p < 0.05) compared to the control group. However, the administration of SR144528 (2 mg/kg) nullified all the protective effects of sumatriptan 0.3 mg/kg.

CONCLUSION

We discovered that CB2 receptors play a crucial role in the favorable effects of sumatriptan on skin flap survival as a novel mechanism of action. So, targeting these receptors seems to be a dependable method in skin flap surgeries to ensure its survival and prevent tissue necrosis. Further experimental and clinical investigations are needed to ensure the safe clinical application of this method.

Assessment of Sumatriptan on Sepsis-Induced Kidney injury in the Cecal Ligation and Puncture Mice Model

Sepsis is a severe systemic inflammatory response with high mortality rate resulting from different microorganisms. Cytokines activation is essential for the immune response, but in painful conditions like sepsis, cytokines act as a double-edged sword and dysregulate immune response which is life-threatening owing to multiple organ dysfunction. The abnormality in 5-HT function is involved in pathological conditions like irritable bowel syndrome, inflammation, myocardial ischemia, itch and renal injury. Sumatriptan, a 5-HT_1B/1D agonist, has anti-inflammatory and anti-oxidative stress effects on animal models. This study was aimed to assess the effects of sumatriptan on kidney injury, the levels of pro-inflammatory cytokines and the percentage of survival in (CLP)-induced sepsis were examined.Cecal ligation and puncture (CLP) model was done on adult C57BL/6 male mice to induce Polymicrobial sepsis. Sumatriptan was injected intraperitoneally 1 h after the sepsis induction by CLP at doses of 0.1, 0.3, and 1 mg/kg in 3 treatment groups. To study the effect of sumatriptan on short-term survival, septic animals were detected 72 h after CLP. Serum levels of TNF-α, IL-1β, IL-6 and IL-10 were evaluated. To study sepsis-induced acute renal failure, kidney functional biomarkers and histopathological alterations were evaluated.Sumatriptan (0.3 mg/kg) administration significantly enhanced survival rate (P<0.01) compared to the CLP group. The beneficial effects of sumatriptan were related to a significant decrease in the pro-inflammatory cytokines and elevated level of IL-10. Sumatriptan presented protective effects on kidney biomarkers and histopathology assay.Anti-inflammatory effects of sumatriptan lead to decrease mortality rate and inflammatory cytokines in CLP induction sepsis in C57BL/6 mice.

Esophagus tissue engineering: from decellularization to in vivo recellularization in two sites

To produce an esophageal scaffold with suitable features and evaluate the result of in vivo cell seeding after its implantation in the omentum and near its original anatomical position in the rat model. The esophagus of twelve rats were resected, cannulated, and decellularized via a peristaltic pump. After confirmation of decellularization and preservation of extracellular matrix, decellularized scaffolds were implanted either in the abdominal cavity (group I, n = 6) or cervical area (group II, n = 6). Histological evaluations were performed after 3 and 6 months of implantation. The results of histological evaluations, scanning electron microscopy, and the tensile test confirmed the maintenance of extracellular matrix and removal of all cellular constituents. At the time of biopsy, no evidence of inflammation was detected and the implanted scaffolds appeared normal. Histopathological evaluations of implanted tissues revealed that undifferentiated cells were seen in scaffolds of all follow-ups in both groups. Epithelial cell seeding was more advanced in biopsies of group II obtained after 6 months of operation and was accompanied by angiogenesis in surrounding adventitia. It seems that the implantation of scaffold near its original place may have an important role in further cell seeding. This method may be surpassing in comparison with traditional implantation techniques for perfecting esophageal transplantation.

The Utility of Phosphohistone H3 in Inter-Observer Variability of Mitotic Count in Meningioma, is There Any Benefit?

Objective:

One of the most reliable and decisive histologic parameters with negative prognostic impact is tumor proliferation capacity . Quantification of mitosis in H&E stained slides could be problematic and is limited by poor reproducibility and lack of objectivity. This study was designed to evaluate inter-observer variability in mitotic count using Phosphohistone H3(PHH3).

Methods:

Totally, 60 specimens with histologic diagnosis of meningioma were selected including 50 grade I, 7 grdae II and 3 grade III tumors. Mitotic figures were counted both in H&E stained sections and slides prepared by immunohistochemistry using Anti-Phosphohistone H3 Anti body by three observers with various level of expertise, independently.

Results:

Mean mitotic count by PHH3 method was higher than H&E staining for all three observers. Observer 1 and 2 revealed good correlation in mitotic count using H&E method, while observer 3 showed disagreement with both of them. However, all of them had good correlation in mitotic count using PHH3 method (cc=0.956,0.947,0.909).

Conclusion:

Based on our findings, PHH3 revealed good agreement between pathologists with various level of expertise and has the capability for further contribution in meningioma grading classification and specially could be beneficial for less experienced pathologists.

Hydrodissection: A Novel Approach for Safe Core Needle Biopsy of Small High-Risk Subcapsular Thyroid Nodules

PURPOSE

To evaluate the safety and effectiveness of core needle biopsy (CNB) under the assistance of hydrodissection (HDS).

MATERIALS AND METHODS

Of 2325 patients requiring biopsy of thyroid lesions, 21 high-risk patients with subcapsular nodules smaller than 10 mm were recruited into this study. All patients underwent HDS with 0.9% saline solution followed by ultrasound (US)-guided CNB with an 18-gauge semi-automated biopsy needle. The separation success rate (SSR) of the HDS, technical success rate (TSR) of CNB, histopathologic success rate (HSR), and complications were assessed.

RESULTS

Both the SSR of HDS and TSR of CNB were 100% (21/21). The HSR of the thyroid nodules was 85.7% (18/21). No major complications were recorded.

CONCLUSION

HDS before CNB can successfully lead to safe biopsy of small subcapsular thyroid nodules.

LEVEL OF EVIDENCE

Level 4, Case Series.

Ivermectin Increases Random-Pattern Skin Flap Survival in Rats: The Novel Role of GABAergic System

BACKGROUND

Ivermectin (IVM) was first used as an antiparasitic agent; however, the role of this drug evolved into a broad spectrum. Many mechanisms have been proposed, including interaction with the GABAergic system. Considering the presence of GABA receptor in the skin tissue and its role in ischemia-reperfusion I/R injury, we aimed to evaluate the effect of IVM through GABA receptors on random-pattern skin flap survival.

METHODS

Sixty Wistar male rats were used. Multiple doses of IVM (0.01, 0.05, 0.2, and 0.5 mg/kg) were injected intraperitoneally before the surgery. Baclofen (selective GABAB agonist) and bicuculline (selective GABAA antagonist) were administered in combination with IVM to assess the role of the GABAergic system. Histopathological evaluations, immunohistochemical staining, quantitative assessment of IL-1β and TNFα, and the expression of GABAA α1 subunit and GABAB R1 receptors were evaluated in the skin tissue.

RESULTS

IVM 0.05 mg/kg could significantly increase flap survival compared with the control group (P < 0.001). Subeffective dose of baclofen (0.1 mg/kg) had synergistic effect with the subeffective dose of IVM (0.01 mg/kg) (P < 0.001), whereas bicuculline 1 mg/kg reversed the effect of IVM (0.05 mg/kg) (P < 0.001). IVM 0.05 mg/kg could also decrease the IL-1β and TNFα levels and increase the expression of GABAA α1 subunit and GABAB R1 receptors in the flap tissue compared with the control group.

CONCLUSIONS

IVM could improve skin flap survival, probably mediated by the GABAergic pathway. Both GABAA and GABAB receptors are involved in this process. This finding may repurpose the use of old drug, "Ivermectin."

SARS-CoV-2: An insight into detection tools

The novel coronavirus disease 2019 (COVID-19), caused by Severe Acute Respiratory Syndrome Coronavirus-2 (SARS-CoV-2), was announced as a pandemic in March 2020. Different diagnostic laboratory tests have been used to detect the infection. Each diagnostic tool, such as Chest Computed tomography (CT) imaging, genome sequencing, nucleic acid amplification methods, whole genome sequencing, microarray, and serology testing have several advantages and disadvantages. Nucleic acid amplification methods are better diagnostic tools for the detection of SARS-CoV-2 in early stages of the infection, while serological tests are more appropriate for the recognition of previously infected patients. In this review, we will briefly consider each diagnostic method, and discuss its pros and cons.

NOL4 is Downregulated and Hyper-Methylated in Papillary Thyroid Carcinoma Suggesting Its Role as a Tumor Suppressor Gene

BACKGROUND

Thyroid cancer is the fourth most common cancer in the world. Papillary thyroid carcinoma (PTC) accounts for 80% of all types of thyroid neoplasm. Epigenetic alterations such as DNA methylation are known as the main cause of different types of cancers through inactivation of tumor suppressor genes.

OBJECTIVES

In the present study, the expression and methylation of suggested gene namely nucleolar protein 4 (NOL4) in PTC in comparison to multi nodular goiter (MNG) have been studied.

METHODS

Forty-one patients with PTC and 38 patients affected by MNG were recruited. Thyroid tissues were obtained during thyroidectomy. RNA and DNA were extracted from thyroid tissues. Quantitative RT-PCR assay was performed for determining the mRNA level of NOL4 while methylation-sensitive high resolution methylation was applied for assessing the methylation status with designing six pairs primers for six regions on gene promoter which were named from NOL4 (a) to NOL4 (f).

RESULTS

Methylation assessment of 81 CpG islands in the promoter region of NOL4 gene revealed that NOL4 (f), the nearest region to the start codon, was significantly hypermethylated in PTC cases compared to MNG cases. NOL4 level in PTC cases in comparison with MNG cases were downregulated. The methylation status and mRNA level of NOL4 (f) were associated with age of diagnosis (Age of the patient at the time of diagnosis), lymph node metastasis, and advanced stages of disease.

CONCLUSIONS

These data suggested an aberrant promoter hyper-methylation of NOL4 in PTC cases may be linked with its downregulation. Therefore, NOL4 gene can be proposed as a potential tumor suppressor gene in PTC tissues.

Sumatriptan improves the locomotor activity and neuropathic pain by modulating neuroinflammation in rat model of spinal cord injury

OBJECTIVES

To investigate the therapeutic effects of sumatriptan in a rat model of spinal cord injury (SCI) and possible anti-inflammatory and analgesic mechanisms underlying this effect.

METHODS

Using an aneurysm mini-clip model of contusive SCI, T9-10 laminectomies were performed for 60 male rats. Animals were divided into six experimental groups (n = 10 per group) as follows: a minocycline administered positive control group, a saline-vehicle negative control group, a sham-operated group, and three experimental groups which received separate doses of sumatriptan (0.1, 0.3 and 1 mg/kg). Behavioural assessments were used to evaluate locomotor activity and neuropathic pain for 28 days. At the end of the study, spinal cord tissues were collected from sacrificed animals for histopathological analysis. Levels of calcitonin gene-related peptide (CGRP) and two pro-inflammatory cytokines (tumor necrosis factor [TNF]-α and interleukin [IL]-1β) were assessed by the enzyme-linked immunosorbent assay (ELISA).

RESULTS

Sumatriptan significantly (P < 0.001) improved the locomotor activity in SCI group. Sumatriptan was also more effective than the positive control, i.e. minocycline (0.3 mg/kg). Additionally, sumatriptan and minocycline similarly attenuated the mechanical and thermal allodynia in SCI (P < 0.001). TNF-α, IL-1β and CGRP levels in sumatriptan- and minocycline-treated groups significantly (P < 0.001) decreased compared to controls. Histopathological analysis also revealed a markedly improvement in hemorrhage followed by inflammatory cell invasion, neuronal vacuolation, and cyst formation in both sumatriptan- and minocycline-treated groups compared to control animals.

CONCLUSIONS

Sumatriptan improves functional recovery from SCI through its anti-inflammatory effects and reducing pro-inflammatory and pain mediators.

Effect of phosphatidylserine on cirrhosis-induced hepatic encephalopathy: Response to acute endotoxemia in cirrhotic rats

BACKGROUND/AIMS

In cirrhosis, the levels of proinflammatory cytokines are high in the liver and blood. Endotoxin decreases level of consciousness in cirrhotic rats. Phosphatidylserine exists in the cell membrane structure and is essential for the survival of neurons. Phosphatidylserine receptor is found in phagocytic cells and also activates the signaling of membrane proteins in apoptotic process. Therefore this study was aimed to explore the hypothesis that hepatic encephalopathy is prevented by phosphatidylserine treatment and if so, whether this is associated with altered level of proinflammatory cytokines in the brain.

METHODS

Cirrhosis was induced by surgical ligation of the bile duct in male Wister rats. The groups were treated with phosphatidylserine and saline for 4 weeks. Brain IL6, TNFα and the expression of phosphatidylserine receptor were assessed. Intraperitoneal injections of either saline or lipopolysaccharide (0.1 mg/kg) were administered to each group. Finally, animal behavior, blood ammonia and the expression of toll like receptor 4 were examined in the brain.

RESULTS

Cirrhosis in rats was associated with altered expression of toll-like receptor4 in brain cortex and phosphatidylserine treatment increases toll-like receptor4 receptor expression. Phosphatidylserine had anti-inflammatory effect in healthy rats but no effect in cirrhotic rats. Chronic phosphatidylserine treatment decreased blood ammonia in BDL cirrhotic rats treated with lipopolysaccharide.

CONCLUSION

The brain of cirrhotic rat is more susceptible to acute endotoxemia and chronic phosphatidylserine treatment decreases blood ammonia and encephalopathy in cirrhotic rats by encountering endotoxin. Phosphatidylserine may boost immune system against endotoxin.

Knowledge of Laboratory Medicine in Medical Students: Is It Sufficient?

Background & Objective

Appropriate use of laboratory testing is essential for achieving safe and effective care to patient. Insufficient knowledge could lead to poor case management and increase the health care costs. It is believed that education on laboratory testing for undergraduate medical student is inadequate. This study was designed to evaluate the level of knowledge of 5 and 6 year undergraduate medical students in field of laboratory medicine.

Methods

Totally, 59 questions including 8 basic questions concerning individual assessment of their knowledge and 51 objective questions focusing on various stages of test ordering and interpretation were asked.

Results

Thirty seven undergraduate medical students at the level of internship participated. On average, 47.9% of students evaluated themselves as "weak" in 8 self-assessment questions. There was no significant difference between responders assessment on their own knowledge in various aspects of laboratory testing (P=0.184). In the objective questions regarding various stages of test ordering including pre-analytic, analytic and post analytic phases,45.6%,51.9% and 50% correct answers were reported ,respectively. Comparison of the level of the knowledge of the students regarding various stages of pathology testing did not show significant difference (P=0.638).

Conclusion

Prioritizing an effective teaching method of laboratory medicine to medical students on appropriate time should be considered in medical school curriculum for better clinical decision making and optimal modern medical care.

Investigation of promoter methylation of FSCN1 gene and FSCN1 protein expression in differentiated thyroid carcinomas

FSCN1 gene encodes an actin-bundling protein, FSCN1, which is involved in formation of actin-based structures that contribute to cell migration. High levels of FSCN1 expression is observed in cells with extended membranes and protrusions. Moreover, up-regulation of FSCN1 has been reported in several epithelial carcinomas. Therefore, FSCN1 is thought to play a role in cell movement and invasion. However, the mechanism behind FSCN1 up-regulation is not known. We investigated the expression of FSCN1 using immunohistochemistry. Methylation-specific PCR was adopted to analyze the methylation status of FSCN1 promoter as a potential regulatory mechanism in FSCN1 expression. The samples included papillary thyroid carcinoma, follicular thyroid carcinoma and goiter samples (controls). Methylation of FSCN1 promoter was observed in 50% of follicular, 48.6% of papillary and 60% of controls. The promoter was unmethylated in 16.7% of follicular samples, 5.7% of papillary samples and 26.7% of controls. In the remaining 33.3% of follicular and 45.7% of papillary samples as well as 13.3% of controls, both methylated and unmethylated alleles were amplified, a condition referred to as semi-methylation. The results showed that FSCN1 promoter was significantly hypomethylated in papillary cases while the methylation status was not significantly altered in follicular cases. On the other hand, FSCN1 was expressed in only nine papillary samples. Regarding protein expression and methylation status, we suggest that hypomethylation of FSCN1 promoter in papillary thyroid carcinoma does not lead to overexpression of FSCN1 and that there might be other regulatory mechanisms involved in FSCN1 up-regulation.

Overexpression of mir-129-1, miR-146b, mir-183, and mir-197 in follicular thyroid carcinoma and adenoma tissues

Follicular thyroid carcinoma (FTC) is responsible for approximately 10% of thyroid malignancies. Since this type of malignancy indicates no capsular and vascular invasions, adenoma and follicular carcinoma of thyroid are not distinguishable. It has been proved that microRNAs, which regulate approximately 30% of coding proteins, have an association with follicular thyroid adenoma (FTA) and carcinoma of the thyroid. Therefore, the aim of this study was to assess the expression of some miRNAs for detecting the most appropriate miRNA as potential biomarker in the diagnosis of FTA and FTC patients. Reverse transcription quantitative polymerase chain reaction (RT-qPCR) was applied to determine the expression levels of miR-129-1, miR-146b,-183 and miR-197 in 48 cases (16 FTC, 16 FTA and 16 hyperplasia/multinodular goiter (MNG) cases). The significance of miRNA differential expression levels among groups were assessed using Multivariate test by Statistical Package for Science Software (SPSS v.20) and Graph Pad Prism v.8. Results indicated that all of the miRNAs had significant overexpression in FTC and FTA versus MNG cases, and also increased expression level in FTC in comparison with FTA, however it was not significant. The results of ROC curve analysis determined the significant overexpression and prognostic value of miR-129-1 in FTA cases and miR-146b in both FTA and FTC cases compared to MNG group. Although all of the earlier mentioned microRNAs were overexpressed in FTC and FTA cases, the ROC curve results demonstrated that miR-129-1 had agreeable AUC for FTA cases. Therefore, it seems that it's cut-off point could be helpful in distinguishing between FTA and multinodular goiter cases. On the other hand, although miR-146b has excellent diagnostic value in both FTA and FTC groups, it seems that this microRNA is unable to act as a specific biomarker to discriminate between FTA and FTC cases. This data need to be confirmed in a large cohort study and other biological samples such as plasma.

Mature Cystic Teratoma of Spinal Cord in a 16-Year-Old Male: A Case Report

Teratoma is a type of multipotential cell tumor, which includes a mixture of two or three germinal layers of ectodermis, endodermis, and mesodermis. Although neonatal sacrococcygeal teratoma has been frequently reported, its occurrence in older age is not common. In this study, we report a rare case of spinal intradural mature cystic teratoma in a 16-year-old male, emphasizing on considering this unusual condition in differential diagnosis of spinal cord cystic tumors.

Utility of PHH3 in Evaluation of Mitotic Index in Breast Carcinoma and Impact on Tumor Grade

Background:

Mitotic activity index is considered as the most important grading component to predict prognosis in invasive breast carcinoma. But it is believed that it is also the cause of discordance in grade estimation based on Bloom-Richardson system. Thus, reproducible methods such as immunohistochemistry (IHC) based analysis methods appears to be of great value in facilitating mitotic count.

Materials and Methods:

In the present study, we examined the utility of Phosphohistone H3 by IHC in various grades of breast carcinoma and compared it with traditional mitotic count by hematoxylin and eosin (H and E) staining and probable changes in tumor grading.

Results:

Total 90 cases of invasive breast carcinoma were evaluated. Mean mitotic count were 8.6 and 6.4/10HPF in IHC and HandE groups, respectively. Although , mean average count was higher by IHC method , good correlation was observed(R=0.914). Using PHH3 IHC, two out of 33 cases of grade I tumors were upgraded in to grade II and three cases of grade II were upgraded in to grade III. None of the tumors were down graded.

Conclusion:

Similar to some other previous studies, we found PHH3 a robust sensitive and practical marker for mitotic count in breast carcinoma. Especially it is helpful to identify the most proliferating area. However, further studies are required to confirm the superiority of this biomarker for including in grading system.

Correction to: Development of an efficient perfusion-based protocol for whole-organ decellularization of the ovine uterus as a human-sized model and in vivo application of the bioscaffolds

This article was unintentionally published twice in this journal, by the same authors. Following should be considered the version of record and used for citation purposes.

A novel polycaprolactone/carbon nanofiber composite as a conductive neural guidance channel: an in vitro and in vivo study

The current study aimed to investigate the potential of carbon nanofibers to promote peripheral nerve regeneration. The carbon nanofiber-imbedded scaffolds were produced from polycaprolactone and carbon nanofibers using thermally induced phase separation method. Electrospinning technique was utilized to fabricate polycaprolactone/collagen nanofibrous sheets. The incorporation of carbon nanofibers into polycaprolactone's matrix significantly reduced its electrical resistance from 4.3 × 109 ± 0.34 × 109 Ω to 8.7 × 104 ± 1.2 × 104 Ω. Further in vitro studies showed that polycaprolactone/carbon nanofiber scaffolds had the porosity of 82.9 ± 3.7% and degradation rate of 1.84 ± 0.37% after 30 days and 3.58 ± 0.39% after 60 days. The fabricated scaffolds were favorable for PC-12 cells attachment and proliferation. Neural guidance channels were produced from the polycaprolactone/carbon nanofiber composites using water jet cutter machine then incorporated with PCL/collagen nanofibrous sheets. The composites were implanted into severed rat sciatic nerve. After 12 weeks, the results of histopathological examinations and functional analysis proved that conductive conduit out-performed the non-conductive type and induced no toxicity or immunogenic reactions, suggesting its potential applicability to treat peripheral nerve damage in the clinic.

Promoter Methylation of Four Tumor Suppressor Genes in Human Papillary Thyroid Carcinoma

BACKGROUND & OBJECTIVE

Papillary thyroid cancer (PTC) is considered to be the most common type of thyroid malignancies. Epigenetic alteration, in which the chromatin conformation and gene expression change without changing the sequence of DNA, can occur in some tumor suppressor genes and oncogenes. Methylation is the most common type of epigenetic alterations that can be an excellent indicator of PTC invasive behavior.

METHODS

In this research, we determined the promoter methylation status of four tumor suppressor genes (SLC5A8, RASSF1, MGMT, and DNMT1) and compared the results of 55 PTC cases with 40 goiter patients. For methylation, we used the methylation-sensitive high resolution melting (MS-HRM) assay technique. The resulting graphs of each run were compared with those of 0%, 50%, and 100% methylated controls.

RESULTS

Our data showed that the promoter methylation of SLC5A8, Ras association domain family member 1(RASSF1), and MGMT were significantly different between PTC tissue and goiter with P-value less than 0.05. The most significant differences were observed in RASSF1; 77.2% of hyper-methylated PTC patients versus 15.6% hyper-methylated goiter samples (P<0.001).

CONCLUSION

RASSF1 promoter methylation can be a PTC genetic marker. RASSF1 promoter methylation is under the impact of the methyltransferase genes (DNMT1 and MGMT), protein expression, and promoter methylation.

Dyspnea as the First Manifestation of Silent Renal Cell Carcinoma

Renal cell carcinoma (RCC) accounts for only 3% of adult malignancies, and the lung is the most common site of metastasis of this tumor, which may be accompanied by pleural metastasis. However, solitary pleural involvement is very rare and its presentation with dyspnea as the first manifestation of RCC is extremely rare.

We describe a 39-year-old male with episodes of dyspnea dating back 6 months prior to hospital admission. During paraclinical investigations, chest computed tomography (CT) demonstrated pleural effusion and multiple pulmonary nodules, raising the question of primary mesothelioma or metastasis from distant focus. Histopathology and immuno- histochemical examinations of pleural biopsy provided evidence of metastatic RCC of the clear cell type. Therefore, an abdominal contrast computed tomography (CT) was performed, revealing a 3 cm right renal mass, which was then removed by partial nephrectomy.

Physicians and pathologists should be aware of unusual presentations of RCC with no symptoms attributable to the kidneys, including dyspnea as in our case.

Heterotopic Pancreas as a Leading Point of Intussusception: A Case Report

Heterotopic pancreas (HP) is generally asymptomatic and found incidentally. It can act very rarely as a leading point for intussusception. Thus, it should be considered as a differential diagnosis of the mass lesions leading to the intestinal intussusception. Herein, we report an unusual case of HP as a cause of ileocolic intussusception.