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Objective: Breast cancer is the second most common cancer in the world. Many metastasis suppressor genes were identified, including the KISS1 gene which encodes for a 145 amino acid protein (kisspeptin-145), which undergoes proteolytic cleavage resulting in kisspeptin-14, -13 and -10. All of these proteins can activate KISS1 receptor (KISS1R). The role of KP/KISS1R signaling in breast cancer remains controversial. The present study aimed to measure mRNA gene expression of KISS1 receptor in healthy and cancerous breast tissue and to evaluate the association of its level with the available molecular subtypes and the traditional clinico-pathological variables. Methods: The study was done on 41 operable primary breast cancer patients. Biopsies from both tumor tissue and surrounding healthy mammary tissue were taken from all patients. KISS1R mRNA expression level was measured using a quantitative real time PCR.   Results: KISS1R mRNA expression was significantly higher in stage III patients compared to stage II patients. At a cut-off value for KISS1R mRNA expression of 1.75, stage II was discriminated from stage III. A significant positive correlation was found between KISS1R mRNA expression and tumor size as well as lymph nodes metastasis. KISS1R mRNA was highly expressed in ER negative cases compared to ER positive ones, and in PR negative cases compared to PR positive ones. There was a statistically significant difference in KISS1R mRNA expression levels and different molecular subtypes being over-expressed in HER2 and triple negative cancer cases. Conclusion: This study supports other studies suggesting that KISS1/KISS1R may not be acting as a metastasis suppressor in breast cancer. KISS1R mRNA is over expressed in advanced stages of breast cancer and hence it can be used as a prognostic marker for aggressiveness of breast cancer. Also being over expressed in triple negative patients, KISS1R could represent a promising therapeutic target in triple negative cases.  相似文献   
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Objectives: Endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) has become the procedure of choice to obtain samples from pancreatic lesions. However, it still has limitations affecting its diagnostic yield. The endoscopic ultrasound-guided fine-needle biopsy (EUS-FNB) needle was developed to allow acquisition of histological core. We conducted this study to compare the diagnostic yield of the Echotip 22Gauge FNA needle with the 22Gauge acquire FNB needle in pancreatic and non-pancreatic lesions. Materials and Methods: This prospective study was carried out on 100 cases of pancreatic and non-pancreatic lesions referred to El-Ebrashi unit of Gastroenterology and Hepatology, internal medicine department, Kasr Al-Aini hospital. The patients included were then randomized for sampling using either the standard Echotip 22Gauge FNA needle or 22Gauge acquire FNB needle. Results: Patients were 57 males and 43 females with a mean age of 58±15 years. Seventy-eight patients had pancreatic lesions, while twenty-two patients had non-pancreatic lesions. Half of the patients (50 cases) underwent EUS-FNA, and the other half (50 cases) underwent EUS-FNB. The presence of adequate tissue core was significantly higher in the FNB group. In contrast, smear cellularity was not significantly different between both groups. FNB had more sensitivity and accuracy depending on cell block/tissue core examination only for diagnosing pancreatic lesions. Blood contamination was higher in cell blocks of the FNA group. The sensitivity, specificity, and accuracy in the combined cytologic and histologic evaluation were 100%. Based on smear only or tissue only, the specificity was 100%, but the sensitivity and accuracy were decreased in both techniques. No complications were reported in both techniques. Conclusion: EUS-guided FNA and FNB are safe with comparable diagnostic accuracy in pancreatic and non-pancreatic lesions. FNB improved the histopathological quality of specimens with little blood contamination. Depending on tissue examination only in diagnosing pancreatic lesions, FNB had more sensitivity and diagnostic accuracy.  相似文献   
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Journal of Clinical Immunology - Inborn errors of immunity (IEI) and autoantibodies to type I interferons (IFNs) underlie critical COVID-19 pneumonia in at least 15% of the patients, while the...  相似文献   
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Background

This study aims at identifying the microbiota in traumatized immature permanent teeth with periapical lesions using Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS).

Methods

The study included 16 immature maxillary central incisors with periapical lesions in 13 patients. Field decontamination and negative control samples were performed before and after access cavity preparation. Root canal samples were taken using sterile stainless-steel hand files following field decontamination. In-office inoculation and pure sub-cultures were performed. Bacterial isolates were prepared for MALDI-TOF MS (Bruker, Billerica, MA USA) analysis using the formic acid extraction method. A comparison of the prevalence of isolated microorganisms was done using a one-sample chi-square test. Comparisons between identified microbial species with the, cone beam computed tomography periapical index (CBCT PAI) scores and lesion volume were also conducted. The Chi-square test was applied to investigate the association between the categorical variables .

Results

Out of the forty isolates recovered from the 16 traumatized teeth included in the present study with the mean patients’ age of 10.93 ± 1.77, 37 isolates were reliably identified by MALDI-TOF MS. Twelve teeth (62.5%) were polymicrobial. The recovered bacteria belonged to five phyla, 15 genera and 25 species. Firmicutes were the predominant phylum (P < 0.001) over Bacteroidetes, Proteobacteria, Actinobacteria and Fusobacteria. Gram positive bacteria were significantly more prevalent than Gram negative (p = 0.03). Facultative anaerobes were the most prevalent (P < 0.001) compared to the obligate anaerobes and the obligate aerobes. The latter were the least prevalent. Statistically, significant differences existed in the comparison between CBCT PAI scores according to bacterial gram staining.

Conclusion

Traumatized immature permanent teeth with periapical lesions showed a significant predominance of Gram-positive facultative anaerobes. MALDI-TOF MS provided accurate identification of numerous viable endodontic microbes.

  相似文献   
6.
Clinical and Experimental Medicine - The SARS-CoV-2 virus has spread to all corners of the world. Thrombosis is the cause of organ failure and subsequent death in COVID-19. The pathophysiology of...  相似文献   
7.
Background

The aim of this study was to evaluate the effects of multi-walled carbon nanotubes/hydroxyapatite (MWCNT/HA) granules with or without leukocyte- and platelet-rich fibrin (L-PRF) on bone regeneration in cancellous bone of sheep model.

Methods

Totally, 32 cylindrical holes were drilled in female sheep (n?=?4) in the distal epiphysis and proximal metaphysis of right and left humerus and femur. The defects were randomly filled with (1) MWCNT/HA, (2) MWCNT/HA mixed with L-PRF, (3) L-PRF, and (4) left empty as control. After 8 weeks, defects were evaluated and compared radiographically using multi-slice computed tomographic (CT) scan and cone beam CT scans, histologically and histomorphometrically.

Results

The results showed that there was no significant inflammation (>?10%) or foreign body reaction around the granules. The new lamellar bone was regenerated around the MWCNT/HA nanocomposite granules. Addition of L-PRF to MWCNT/HA demonstrated significantly improvement of new bone formation, about 27.40?±?1.08%, in comparison with the L-PRF alone, about (12.16?±?1.46%) (P?<?0.01). Also, the rate of new bone formation was significantly greater with the use of MWCNT/HA granules (24.59?±?1.54%) compared to the control (10.36?±?1.17%) (P?<?0.01).

Conclusion

Consequently, both biocompatibility and osteoconductivity of MWCNT/HA nanocomposite were demonstrated in the preclinical sheep model, and the use of L-PRF in combination with MWCNT/HA nanocomposite can improve bone regeneration.

  相似文献   
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BACKGROUND Nonalcoholic fatty liver disease(NAFLD)and type-2 diabetes mellitus(T2DM)have an intricate bidirectional relationship.Individuals with T2DM,not only have a higher prevalence of non-alcoholic steatosis,but also carry a higher risk of progression to nonalcoholic steatohepatitis.Experts still differ in their recommendations of screening for NAFLD among patients with T2DM.AIM To study the prevalence of NAFLD and advanced fibrosis among our patient population with T2DM.METHODS During the study period(November 2018 to January 2020),59 adult patients with T2DM and 26 non-diabetic control group individuals were recruited prospectively.Patients with known significant liver disease and alcohol use were excluded.Demographic data and lab parameters were recorded.Liver elastography was performed in all patients.RESULTS In the study group comprised of patients with T2DM and normal alanine aminotransferase levels(mean 17.8±7 U/L),81%had hepatic steatosis as diagnosed by elastography.Advanced hepatic fibrosis(stage F3 or F4)was present in 12%of patients with T2DM as compared to none in the control group.Patients with T2DM also had higher number of individuals with grade 3 steatosis[45.8%vs 11.5%,(P<0.00001)and metabolic syndrome(84.7%vs 11.5%,P<0.00001)].CONCLUSION A significant number of patients with T2DM,despite having normal transaminase levels,have NAFLD,grade 3 steatosis and advanced hepatic fibrosis as measured by liver elastography.  相似文献   
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