Substance P augments the rate of vasodilation induced by calcitonin gene-related peptide in porcine ophthalmic artery in vitro.

Peptides may function as neurotransmitters liberated antidromically by sensory nerve fibres, provoking vascular responses having potential importance in some neurological disorders. Dose-response relaxation curves induced by substance P (SP) and calcitonin gene related peptide (CGRP) have been studied in porcine ophthalmic arteries in vitro. Both peptides induced vasodilation when tested separately (CGRP much greater than SP). Because of the putative interactions between such peptides in this vascular territory, a computerised system was also used for analysing over time the response to a single addition of either 10(-8) M CGRP, 10(-8) M SP or a combination of 10(-8) M SP + 10(-8) M CGRP. SP did not augment the maximum relaxation induced by CGRP alone, but increased significantly the rate of relaxation during the initial phase of the response. The effect induced by the SP+CGRP combination was stronger than the sum of the individual SP and CGRP-induced relaxations during the first 4 min of the response, which suggests a SP-CGRP synergism in this artery.     

HLA-DR-restricted antigen-induced proliferation and cytotoxicity mediated by CD4+ T-cell clones from subjects vaccinated with killed M. leprae

Thirteen CD4+ T-cell clones raised against Mycobacterium leprae from three M. leprae-vaccinated subjects were studied for major histocompatibility complex (MHC) restriction in proliferative and cytotoxicity assays. These T-cell clones recognized at least nine different epitopes, ranging from M. leprae-specific to broadly crossreactive. Restriction studies with a panel of antigen-presenting cells (APCs) suggest that all of the T-cell clones recognized antigens in the context of the DR locus. Three T-cell clones with three different reactivities from a DR1, 2-positive subject responded to M. leprae in proliferation and cytotoxicity when the antigen was presented in the context of DR1-positive APCs. Four T-cell clones responding to M. leprae-specific or crossreactive epitopes from the second donor, who was DR4,DW4; DR4,Dw14-positive, and a single M. leprae-specific T-cell clone from the third subject, who was DR3,4:Dw4, recognized the antigens in the presence of Dw4 APCs. Four crossreactive T-cell clones from the second subject responded in the presence of Dw14-positive APCs, and one limited crossreactive clone recognized the antigen in the context of DR4 and DR7-positive cells, suggesting that its response was restricted by a common determinant. The T-cell clones that recognize the 65-kDa, 18-kDa, and 13B3 recombinant M. leprae antigens in proliferative assays were cytotoxic for autologous adherent cells pulsed with the respective antigens.(ABSTRACT TRUNCATED AT 250 WORDS)     

Neuroendocrine differentiation in carcinoma of the breast. Tyramide signal amplification discloses chromogranin A-positive tumour cells in more breast tumours than previously realized

The aim of the study was to determine if, by means of tyramide signal amplification (TSA), the presence of chromogranin A (CgA)-positive tumour cells could be demonstrated in breast cancer cases found to be negative by conventional immunohistochemical staining. Sections from 44 cases of breast cancer (28 infiltrating ductal carcinomas, 2 lobular carcinomas, 4 ductal carcinomas in situ (DCIS), 7 lobular carcinomas in situ (LCIS), and 3 mucinous carcinomas) were stained for CgA by conventional immunohistochemical methods and by immunohistochemistry with TSA. The sections were also histologically graded and their oestrogen receptor (ER), progesterone receptor (PgR) and HER-2 oncogene status was recorded. Five of the tumours showed CgA-positive staining with the polyclonal antibody 430 with conventional methods. Thirty cases showed CgA-immunoreactive tumour cells after immunohistochemical staining with the polyclonal antibody 430 with TSA. However, eight of these also showed faint staining with the negative control antibody X0936 with TSA. One case showed immunopositivity for CgA using a monoclonal antibody without tyramide amplification and only a further two cases were positive when TSA was applied. The presence of CgA appears to be associated with a lower histological grade and may be more often found in oestrogen receptor-positive tumours.     

Ultrastructure and chromogranin A immunogold labelling of ECL cell carcinoids

Poorly differentiated neuroendocrine cells can be difficult to recognise. Sensitive methods are needed to label cells that have lost their ultrastructural features and have reduced concentrations of neuroendocrine markers. In gastric neoplasms, enterochromaffin-like cells might dedifferentiate and lose their characteristic granules and secretory vesicles, making detection of such cells increasingly difficult. However, chromogranin A (CgA) immunogold labelling could provide sensitive and specific detection of gastric neuroendocrine cells. We present ultrastructural findings, CgA immunogold labelling as well as conventional immunohistochemical findings of two human enterochromaffin-like cell carcinoids. Electron-dense granules of poorly differentiated cells were less intensely labelled than granules in well-differentiated cells. Granules with atypical shape as well as punctuate granules previously found in neuroendocrine neoplasms were also CgA labelled. The CgA labelling efficacy after antigen retrieval in an alkaline solution was higher after heating in an autoclave at 135 degrees C compared to a microwave at 100 degrees C for both granules and secretory vesicles without significant deterioration of the ultrastructure. In conclusion, the use of CgA immunogold labelling could ensure a specific classification of cells with neuroendocrine granules and be a supplement to immunohistochemical examination of poorly differentiated tumours.     

The PAS positive material in gastric cancer cells of signet ring type is not mucin

Purpose

The purpose of this study is to assess the exocrine and neuroendocrine properties of tumour cells in diffuse gastric cancer with signet ring cell differentiation.

Material and methods

Mucin mRNA and protein expressions (MUC1, 2, 3, 4, 5AC, 6 and MUC13) were assessed by immunohistochemistry and in situ hybridization. The neuroendocrine properties were evaluated by protein and mRNA expression of the general neuroendocrine markers chromogranin A and synaptophysin.

Results

No MUC expression was observed in signet ring tumour cells including the amorphous substance in any of the nine cases. All cases showed immunoreactivity to synaptophysin, and seven out of nine cases immunoreactivity to chromogranin A in signet ring and non-signet ring tumour cells. Chromogranin A mRNA expression was observed in tumour cells in all samples with retained mRNA.

Conclusions

The lack of MUC protein and mRNA in signet ring tumour cells suggests the amorphous substance is not mucin. The lack of MUC mRNA expression in non-signet ring tumour cells questions exocrine differentiation in this tumour group. The abundant protein expression of the general neuroendocrine markers CgA and synaptophysin, and mRNA expression in tumour cells strengthens the hypothesis that this tumour group may be of neuroendocrine origin.     

Gastric neuroendocrine carcinoma after long-term use of proton pump inhibitor

We present a case of a gastric neuroendocrine carcinoma in a patient with a history of long-term proton pump inhibitor (PPI) use. A 49-year-old man using PPI for the last 15 years due to gastroesophageal reflux disease developed progressive dysphagia, dyspepsia and weight loss. Upper gastrointestinal endoscopy, endoscopic ultrasonography and abdominal CT diagnosed a malignant tumor localized to a hiatal hernia. Fasting serum chromogranin A and gastrin concentrations were elevated (32 nmol/l and 159 pmol/l, respectively). Helicobacter pylori PCR analysis of antral biopsies was negative. Biopsies from endoscopically normal oxyntic mucosa showed enterochromaffin-like (ECL) cell hyperplasia. Tumor biopsies revealed a poorly differentiated neuroendocrine carcinoma. Sevier-Munger staining, immunohistochemistry and electron microscopy indicated ECL cell as origin of the tumor cells. Concerns have previously been raised about the safety of long-term PPI use due to a possible increased risk of cancer. This case illustrates a patient with a poorly differentiated neuroendocrine carcinoma with ECL cell characteristics probably induced by hypergastrinemia secondary to long-term PPI use.     

Laparoscopic occlusion compared with embolization of uterine vessels: a randomized controlled trial

OBJECTIVE: To compare clinical outcome 6 months after treatment with bilateral laparoscopic occlusion of the uterine artery versus uterine leiomyoma embolization. METHODS: Sixty-six premenopausal women with symptomatic uterine leiomyomata were randomized to treatment with either laparoscopic occlusion of uterine arteries or uterine leiomyoma embolization. The primary outcome was reduction of blood loss from pretreatment to 6 months postoperatively, measured by a Pictorial Bleeding Assessment Chart. Secondary outcomes included patients' own assessment of symptom reduction, postoperative pain assessed using visual analog scales, ketobemidone used postoperatively, complications, secondary interventions, and failures. RESULTS: Fifty-eight women were included; 6-month follow-up data were available for 28 participants in each group. The percentage reduction in Pictorial Bleeding Assessment Chart scores did not differ between the treatment groups (52% after uterine leiomyoma embolization and 53% after laparoscopy, P=.96). The study had 52% power to detect a 20% difference on the Pictorial Bleeding Assessment Chart. Fewer participants in the group treated with uterine leiomyoma embolization complained of heavy bleeding after 6 months (4% compared with 21%, P=.044). The postoperative use of ketobemidone was higher after uterine leiomyoma embolization (46 mg compared with 12 mg, P<.001). CONCLUSION: Both laparoscopic occlusion of uterine vessels and embolizaton of uterine leiomyoma improved clinical symptoms in the majority of patients. Participants with the laparoscopic procedure had less postoperative pain but heavier menstrual bleeding 6 months after treatment. A larger study and longer follow-up is necessary before a definite conclusion can be made regarding the most effective treatment. CLINICAL TRIAL REGISTRATION: (www.ClinicalTrials.gov), NCT00277680 LEVEL OF EVIDENCE: I.     

Current treatment options for abnormal uterine bleeding: an evidence-based approach

Heavy menstrual bleeding is the predominant complaint in women with abnormal uterine bleeding. Treatment options are drug therapy, and first- and second-generation endometrial resection. Many women will subsequently have a hysterectomy. Uterine fibroids are the most common solid pelvic tumours in women, and although many fibroids seem to cause no symptoms, they can have serious adverse effects and impact on quality of life. As women postpone having children, gynaecologists will have to manage fibroids and polyps in a conservative manner. The past decade has witnessed the development of highly sophisticated diagnostic and therapeutic technology for women suffering from menorrhagia, fibroids and polyps, including minimally invasive uterine therapy. The tools currently at our disposal permit greater management flexibility, which must be tailored to the individual clinical situation. This chapter reviews the evidence-based approach and minimally invasive therapy.     

Cytotoxicity of streptozotocin on neuroendocrine cells of the pancreas and the gut

Streptozotocin has been used to induce diabetes mellitus in experimental animals and has been thought to have a selective cytotoxic effect on the -cells in the islets of Langerhans. The aim of the present study was to determine whether streptozotocin has any cytotoxic effect on other neuroendocrine cells of the gastrointestinal tract. Eight female Sprague-Dawley rats received intraperitoneal injections of 100 mg/kg streptozotocin in citric acid buffer; the concentration of streptozotocin was adjusted to 25 mg/ml buffer. Seven rats, serving as controls, received an equivalent volume of the vehicle. The rats were killed after three days and the fundus, antrum, small intestine and pancreas were examined for neuroendocrine cells. Our study confirms that streptozotocin is cytotoxic towards -cells. In addition, it is cytotoxic towards neuroendocrine cells of the oxyntic mucosa of the stomach. This finding may have clinical significance and suggests that streptozotocin may be used in the treatment of gastric neuroendocrine tumors as well as insulinomas.