Comparison of quantum dot immunofluorescence histochemistry with conventional immunohistochemistry in detecting Helicobacter pylori infection in paraffin-embedded tissues of gastric biopsy.

Quantum dots (QDs) are a new type of fluorescent label, which has been widely used in many biological and biomedical imaging applications. In this study, we used QDs-based immunofluorescence histochemistry (QDs-IHC) and conventional immunohistochemistry (IHC) techniques to perform a retrospective analysis on paraffin-embedded tissues of gastric biopsies in 203 patients (112 of which were HP positive and 91 were negative). The ability of QDs-IHC to detect Helicobacter pylori (HP) in gastric biopsies compared to IHC technology was evaluated. In our study, both methods showed consistent HP morphology and localization. The positive detection rate of HP for QDs-IHC in formalin-fixed and paraffin-embedded (FFPE) tissue was 54.7% (111/203), and the sensitivity and specificity reached 99.11% and 100%, respectively. However the positive detection rate of HP for IHC was 53.7% (109/203), with a sensitivity and specificity of 97.32% and 100%, respectively. Weak positives (1+) were detected in 2 case of QDs-IHC with negative in IHC, and moderate positives (2+) were detected in 3 case of QDs-IHC with weak positives (1+) in IHC. The consistency test showed that the two methods showed good agreement (κ = 0.980, P = 0.014), but the sensitivity of QDs-IHC was slightly higher than that of conventional IHC. Our results show that QDs-IHC has strong sensitivity and high specificity. It is superior to conventional IHC in detecting HP infection in FFPE tissues of gastric biopsy, especially in tissues with low HP content.

Ovarian dysgerminoma detected by 18F-FDG PET/CT technique: A case report.

INTRODUCTION: Ovarian dysgerminoma (OD) mostly affect young women, have a rapid growth rate, and could result in complications such as rupture, hemoperitoneum or torsion, and acute abdomen. However, there have been no reports of OD on F-FDG PET/CT imaging. PATIENT CONCERNS: A 21-year-old female patient was admitted to our hospital on February 6, 2016, due to "reduced menstrual flow with abdominal distension for 3 months". DIAGNOSIS: Color Doppler ultrasound showed a large solid mass in the abdomen and pelvis. Serum carbohydrate antigen 125 (CA125) was elevated significantly. Subsequent computed tomography (CT) of chest showed a large effusion in the right thoracic cavity. Abdominal CT scan revealed the presence of a solid mass occupying a large space in the middle and lower abdomen, suggesting that it derived from the left ovary. Then, she underwent F-fluoro-2-deoxy-D-glucose (F-FDG) positron emission tomography (PET)/CT examination for further diagnosis and staging. PET/CT showed a large occupying lesion in the abdomen. The maximum standardized uptake (SUVmax) of F-FDG was 15.8. No obvious hypermetabolic metastases were observed in the other parts of the body. Postoperative pathology and immunohistochemistry confirmed the ovarian dysgerminoma. INTERVENTIONS: The patient underwent surgery. Chemotherapy was successfully carried out post-operation. OUTCOMES: Fortunately, the patient is responding well to treatment and the postoperative recurrence-free survival time has been more than 3 years. CONCLUSION: OD usually occurs in young women and is characterized by large solid pelvic mass. The F-FDG PET/CT scan shows abnormally increased metabolism of the tumor. Because of the high metabolic characteristics, F-FDG PET/CT may be of great significance in the diagnosis and staging of OD.

Hyalinizing trabecular tumor of the thyroid: a clinicopathological analysis of four cases and review of the literature.

OBJECTIVE: To explore the clinicopathological features, diagnosis and differential diagnosis of hyalinizing trabecular tumor (HTT) of the thyroid. METHODS: The four HTT specimens were collected including demographics, clinical information, relevant images, the extent of thyroidectomy, the follow-up and representative pathological data of tumors were available for analysis. In addition, the immumohistochemical staining related to the tumor as well as the BRAF and N-ras mutation analysis were analysed. RESULTS: The mean age of four patients was 47 years old and the mean size of the tumor was 2.8 cm. Most of the patients were asymptomatic, while detecting incidentally by using neck ultrasound test. Ultrasound imaging of all cases showed demarcated substantial hypoechoic nodules in ipsilateral thyroid lobe. Computed Tomography (CT) showed a clear low density shadow in the affected thyroid lobe. Tumors of three cases were located at the left, but the other one was located at the right thyroid gland with a complete fibrous capsule. The cytological features resembled papillary thyroid carcinoma (PTC). The histological test indicated that the tumors had characteristic of trabecular growth pattern with hyalinizing material. The tumor cells were in shape of polygonal, oval or high columnar with an acidophilic or clear cytoplasm. The nuclei were oval with inconspicuous small nucleoli, prominent grooves and pseudoinclusion body in cell nucleus. Mitosis and psammoma bodies were rare to be observed. Cytoplasmic "yellow bodies" were frequently observed. The hyaline material was prominent, with positive periodic acid-Schiff (PAS) and negative Congo red staining. Immunohistochemically, tumor cells were positive for thyroglobulin (Tg), thyroid transcription factor-1 (TTF-1), CD56 and negative for calcitonin, cytokeratin 19 (CK19), HBME-1, S-100 and synaptophysin (SyN). Chromogranin A (CgA) and galectin-3 were expressed weakly in some cases. Staining with the MIB-1 antibody showed membranous/cytoplasmic immunoreactivity. Whereas, another clone of Ki-67 (SP6) showed a common nuclear pattern with an index of <1%. None of the four cases exhibited the BRAF V600E protein reactivity. Gene mutation analysis demonstrated no BRAF and N-ras mutation. There was no evidence of local recurrence or metastasis after 6 to 36 months of follow-up. CONCLUSIONS: HTT is an uncommon thyroid tumor with very low malignant potential. It has no particular clinical features, so it's often misdiagnosed in fine needle aspiration cytology (FNAC)/Ultrasonography-guided fine needle aspiration cytology (US-FNAC) and frozen section (FS). Its final diagnosis mainly relies on typical histopathological features and characteristic expression pattern of MIB-1 immunohistochemical staining.

Immunoglobulin G Expression in Human Sperm and Possible Functional Significance.

Immunoglobulin G (IgG), the major molecule of the immune system, which was traditionally thought to be produced by differentiated B-lymphocytes, had recently been found in non-immune cells including spermatozoa of rabbit testis. To study if human sperms could produce IgG that might play a role in fertilization, we employed immunofluorescent staining, Western blot, in situ hybridization, RT-PCR (reverse transcription polymerase chain reaction) and immunoelectron microscope and found that human sperms were capable of synthesizing IgG. IgG protein and mRNA were detected in the cytoplasm, mainly the neck region of the sperm and IgG immunoreactivity was found to cover the entire sperm cell. The essential enzymes necessary for IgG synthesis and class switching, RAG1 (recombination activating gene 1), RAG2 (recombination activating gene 2) and AID (activation-induced cytidine deaminase), were also detected in the sperm cells. Furthermore, we found that anti-IgG antibody could inhibit sperm from penetrating Zona-free hamster egg with statistical significance. These discoveries suggested that immunoglobulin G could be produced by human sperms and it might play a role during fertilization.

Pancreatic Expression of Immunoglobulin G in Human Pancreatic Cancer and Associated Diabetes.

OBJECTIVES: The prognosis of pancreatic cancer (PC) is poor and the pathogenesis of PC-associated diabetes is unknown. We investigated the possible expression of immunoglobulin G (IgG) in human pancreatic carcinomas and adjacent pancreatic islets to gain a better understanding of these diseases. METHODS: We employed immunohistochemistry, Western Blot, real-time polymerase chain reaction, and in situ hybridization to examine IgG expression in PC tissues and adjacent islets with and without cancer-associated diabetes. The IgG mRNA and IgG synthesizing-related enzymes were examined in PC cell lines. The IgG expression and secretion were downregulated with specific small interfering RNA and antibody to IgG followed by flow cytometry to assess its effect on apoptosis of cultured PC cells. RESULTS: The expression of IgG was detected in pancreatic carcinoma and adjacent islets. Small interfering RNA and antibody treatments induced apoptosis in PC cell lines. In the carcinoma tissue, the levels of IgG expression varied depending on the stages of the cancers with more malignant cancers expressing more IgG (P < 0.05). The IgG levels in cancer cells were also increased when the patients had diabetes or hyperglycemia (P < 0.05). In addition, the extent of IgG expression in the seemingly normal islet cells adjacent to the tumor varied in relation to the grade of cancer differentiation and distance to the cancer nests. CONCLUSIONS: (1) Immunoglobulin G was locally produced by PC cells and adjacent islet cells. (2) Immunoglobulin G may promote tumor growth by inhibiting cancer cell apoptosis. (3) Locally produced IgG might play a role in PC-associated diabetes.