Relationship Between Changes of Active Oxygen Metabolism and Blood Flow and Formation, Progression, and Recovery of Lesions in Gastric Mucosa of Rats with a Single Treatment of Compound 48/80, a Mast Cell Degranulator

The relationship between the changes of activeoxygen metabolism and blood flow and the formation,progression, and recovery of lesions was examined in thegastric mucosa of rats treated once with compound 48/80, a mast cell degranulator. Gastricmucosal lesions appeared 0.5 hr after compound 48/80treatment, became worst at 3 hr, and recovered fairlywell at 12 hr. Increases in gastric mucosal lipidperoxide content and xanthine oxidase andmyeloperoxidase activities and decreases in gastricmucosal vitamin E and hexosamine contents andSe-dependent glutathione peroxidase activity occurredwith the formation and progression of gastric mucosal lesions.These changes were attenuated with the recovery of thelesion. Gastric mucosal nonprotein SH content decreasedwith the formation of gastric mucosal lesions, and this decreased SH content returned to nearthe original level with lesion progression. No changesin gastric mucosal superoxide dismutase and catalaseactivities occurred with the formation, progression, and recovery of gastric mucosal lesions.Gastric mucosal blood flow decreased with the formationof gastric mucosal lesions, and this decreased bloodflow recovered with lesion progression. Serum serotonin concentration, an index of mast celldegranulation, increased with the formation of gastricmucosal lesions, and this increased serotonin level wasattenuated with lesion progression and recovery.Pretreatment with ketotifen, a connective tissue mast cellstabilizer, prevented the formation of gastric mucosallesions, the increases of gastric mucosal lipid peroxidecontent, xanthine oxidase and myeloperoxidase activities, and serum serotonin level; and thedecreases of gastric mucosal nonprotein SH content,glutathione peroxidase activity, and blood flow found at0.5 hr after compound 48/80 treatment. These results indicate that the changes of gastric mucosalactive oxygen metabolism and blood flow are closelyrelated to the formation, progression, and recovery ofgastric mucosal lesions in rats with a single compound 48/80 treatment. The present results alsosuggest that this compound 48/80-induced gastric mucosalinjury could be a kind of ischemia-reperfusion-inducedinjury occurring through degranulation of connective tissue mast cells.     

Evaluation of pulmonary infiltrates in patients after stem cell transplantation

Hematopoietic stem cell transplantation is potentially curative therapy that has become the standard of care for many hematologic malignancies. Pulmonary complications occur in about 50% of stem cell transplant recipients and no other organ dysfunction has a higher mortality. Unfortunately the diagnosis of these infiltrates is hampered by the poor yield from routine studies and this patient population is rarely able to tolerate more risky procedures that will obtain tissue for microscopy and culture. A bronchoalveolar lavage (BAL) is usually insufficient to make a diagnosis of invasive fungal, significant bacterial, or pathogenic viral infections in patients that will still benefit from a change in therapy. In this review we discuss the infectious etiologies of pulmonary infiltrates post hematopoietic stem cell transplant, the non-infectious causes of infiltrates such as diffuse alveolar hemorrhage, engraftment syndrome, and idiopathic pneumonia syndrome, and the yield of newer diagnostic procedures ranging from peripheral blood galactomannan to cytomegalovirus antigenemia, and report on new technologies that promise more accurate and timely diagnoses of these infiltrates.     

CMED in the treatment of nasal natural killer cell lymphoma with distant metastases

Introduction: Nasal natural killer (NK) cell lymphoma that showed distant metastases generally showed an poor prognosis. We described a group of patients with these atypical presentation and that were treated with an intensive, short chemotherapy/radiotherapy regimen.

Methods: Sixty-one patients fulfilled the criteria for NK cell lymphoma with distant metastases and all have very poor prognostic factors: high clinical risk, multiple extranodal presentation and bulky disease (tumor mass >10 cm). They were treated with CMED (cyclophosphamide 2000 mg/m², iv, day 1, methotrexate 400 mg/m², iv, day 1(with leucovorin rescue), etoposide 400 mg/m² twice and dexametasone 40 mg daily for 4 days). If complete response (CR) was observed, they were received adjuvant radiotherapy (50 Gy) to nasal region. Patients with failure were treated with different salvage treatments.

Results: Forty nine patients achieved CR and 12 were considered failure, all patients that were failure and nine that relapse die secondary to tumor progression. Median follow-up were 46 months (range 34-68 months). Median has not been observed in relapse-free survival (RFS) and overall survival (OS). Actuarial curves at 5 years showed that RFS was 81% and OS was 65%. Treatment was well tolerated.

Conclusions: Nasal NK cell lymphoma with distant metastases is considered an rare clinical entity, probably is under diagnosis because it has been included as stage III and IV in previous reports, that showed an very poor RFS and OS. The treatment herein report could achieve good response and outcome, but it is evident that more specific and aggressive therapy is necessary in these setting of patients.     

Thirty-nine cases of pure red cell aplasia: A single center experience from India

Pure red cell aplasia (PRCA) is an uncommon disorder, characterized by transfusion dependent anemia, reticulocytopenia with selective aplasia or paucity of erythroid cells in bone marrow. There are only a few large series of PRCA reported in literature. This is the largest single center series of PRCA from India.

Objective: To evaluate the utility of Immunohistochemistty with Glycophorin A on bone marrow biopsies in quantitating the cut-off percentage of erythroid blasts required for diagnosis, as the upper cut-off percentage of erythroblasts for establishing a diagnosis of PRCA is still not clear.

Methods: The clinical data were obtained from patients' case files. Immunohistochemistry with Glycophorin A was performed using an immunoperoxidase technique and percentage of Glycophorin A positive cells of all nucleated cells was calculated by two independent observers.

Results: In our study, bone marrow aspirates showed a variable percentage of erythroblasts ranging from 2 to 12% (mean 6.3%) in children and from 1 to 8% (mean 4.6%) in adults on Giemsa smears. Immunohistochemistry (IHC) with Glycophorin A showed a mean positive cell % of 8.2 (range 2–16%) and 6.8 (1–9%) in pediatric and adult respectively against a mean of 28% (range 21–39%) in idiopathic thrombocytopenia (ITP) cases. Treatment with prednisone showed good response in a majority of both adults and childhood PRCA. Cyclosporine was found to be a good alternative in prednisone non-responders. Thymectomy was beneficial in patients with thymoma.

Conclusion: A higher percentage of erythroid cells (>5%) does not exclude a diagnosis of PRCA in an appropriate clinical setting and therefore can be managed as PRCA.     

IgA anti-red blood cell auto-antibodies in Evans syndrome

In Evans syndrome, IgG auto-antibodies (Abs) and/or complement components are frequently detected on red blood cells (RBC) in the direct antiglobulin test (DAT). A 70-year-old man with Evans syndrome diagnosed four years previously presented with a persistent autoimmune haemolytic anaemia, despite immunosuppressive treatment and normalization of platelet count. The RBC allo- and auto-Abs screening and identification were performed by indirect antiglobulin test (IAT) and DAT. In March 2006, no circulating anti-RBC auto-Abs were found in IAT but the DAT was positive with anti-IgG (++),-C3d (weak) and -IgA (++). Follow up for 11 months revealed anti-RBC IgA auto-Abs on five out of six samples. IAT was positive for RBC auto-Abs on three samples. No correlation between the haemoglobin level and the strength of reactivity of IgG and IgA auto-Abs was observed. IgA anti-RBC auto-Abs are present in Evans syndrome. To detect these Abs and characterize their role, DAT procedures should systematically include anti-IgA.     

Proliferating Cell Nuclear Antigen Expression in Peribiliary Glands of Stone-Containing Intrahepatic Bile Ducts

All cases of hepatolithiasis showed features ofchronic proliferative cholangitis, and it has beenspeculated that the atypical glandular proliferationmight be a precursor to overt cholangiocarcinoma. Proliferative cell nuclear antigen (PCNA) is anuclear protein synthesized in the G₁/S phaseof the cell cycle and therefore is related to cellproliferative activity. In an attempt to assess the activity of cell proliferation ofstone-containing intrahepatic bile ducts, we conducteda study using immunohistochemical staining withmonoclonal antibody to score PCNA in intrahepatic bileducts. Thirty patients (10 men, 20 women; mean age52.4 years) having hepatolithiasis surgically resectedwere studied. Ten stone-free patients served ascontrols. All 40 specimens were immunostained for PCNA using PC 10 monoclonal antibody. PCNA of bothstone-containing and stone-free intrahepatic bile ductswere assessed by counting positive staining nuclei per500 cells and expressed as labeling index (LI), ie, percentage of positive nuclei to the totalnumber of nuclei. The PCNA LI in stone-free intrahepaticbile ducts was generally low: 10.0 ± 13.2%, 10.4± 10.7% and 7.9 ± 9.6% for extramuralglands, intramural glands, and epithelial lining,respectively. In contrast, the PCNA LI forstone-containing intrahepatic bile ducts weresignificantly higher than those of controls (P <0.001): 49.4 ± 8.3%, 40.6 ± 7.0% and 34.1± 6.8% for extramural glands, intramural glands,and epithelial lining, respectively. The extramuralglands had a significantly higher PCNA LI (P < 0.001)than the intramural glands and controls. Hyperplasia was found inall specimens, while dysplasia was found in six of 30cases with hepatolithiasis. The dysplastic cells alsohad a higher PCNA LI (P < 0.001) than thehyperplastic cells and normal epithelium. Our findingsshowed that there is marked increase of activity of cellproliferation in stone-containing intrahepatic bileducts. It is well known that genetic mutations are facilitated in proliferating cells. Therefore,our results suggest that the high epithelial turnover indysplastic cells and extramural glands had higherpotential for proliferation and neoplastictransformation in long-standing untreatedhepatolithiasis.     

Response of Human Insulinoma Cells to Extracellular Calcium Is Different from Normal B Cells

The preoperative determination of thelocalization of a small insulinoma is sometimesdifficult using routine imaging techniques. We have usedthe selective arterial calcium injection (SACI) test todetermine the location of the tumor preoperatively. Thepathophysiologic basis of the SACI test is based on theresponsiveness of insulinomas to calcium injected intothe feeding artery. In this study, we demonstrated the in vitro response of the insulinoma cellsto the extracellular calcium challenge by usingprimary-cultured insulinoma cells. Human insulinomacells were obtained from three patients. MIN6 cells(normal pancreatic B cells) were used as a control;their insulin response to various stimuli resembles thatof normal B cells. The insulin secretory dynamics inresponse to extracellular calcium were observed using a perfusion system. Second, the change ofthe concentration of cytosolic free calcium([Ca²⁺]_i) was monitored byfluorometry using fura-2/AM. When the concentration ofextracellular calcium ([Ca²⁺]_o) was changed from 2.54 mM to 10 mM, insulinsecretion from the insulinoma cells was markedlyincreased within 6 min (10- to 18-fold at maximum), andrapidly returned to the basal level; at the same time, [Ca²⁺]_i was immediatelyelevated and reached a peak within 1 min. In contrast,in the MIN6 cells, the insulin secretion and [Ca2+]iwere not significantly changed when[Ca²⁺]_o was switched to 10 mM. The results of these in vitro experiments agreedwith the clinical results of the SACI test. The positiveresponse of the insulinoma to the SACI test is probablydue to the different response of insulinoma cells to the extracellular calcium challengecompared with normal B cells. The role of[Ca²⁺]_i may be important in themechanism underlying the SACI test.     

Inhibition of DNA Synthesis in Caco-2 Cells by Oxidative Stress (Amelioration by Epidermal Growth Factor)

The role of oxidative stress in the regulationof intestinal epithelial proliferation was examined byevaluating the effect of H₂O₂andxanthine oxidase + xanthine (XO + X) on[³H]thymidine incorporation into DNA in Caco-2 cells. DNAsynthesis was highest 4 and 5 days after seeding, whileit declined rapidly between 5 and 12 days. Pretreatmentfor 0.5-24 h with H₂O₂or XO + X reduced DNA synthesis on 4- to6-day-old, but not on 7- to 20-day-old cells. The effectof XO + X on DNA synthesis was significantly reduced bycatalase, superoxide dismutase, and ferric chloride, but pretreatment with deferoxamine potentiatedXO + X-induced inhibition of DNA synthesis.Coadministration of epidermal growth factor (EGF) for 24hr reduced the H₂O₂and XO +X-induced inhibition of DNA synthesis; this effect of EGFwas not observed up to 8 hr. Results show thatO_2-and H₂O₂rapidlyinhibit DNA synthesis in Caco-2 cells and that EGFrestores DNA synthesis in oxidant-treatedcells.     

Autoradiographic and confocal laser microscopic observation show lafutidine binds to CGRP-immunoreactive nerves as well as gastric parietal cells

The present study was undertaken to observe the binding sites of lafutidine, a newly invented H₂ receptor antagonist ((+/-)-2-(furfurylsulfinyl)-N-[4-[4-(piperidinomethyl)-2-pyridyl]oxy-(Z)-2 butenyl] acetamide), in the Mongolian gerbil and human gastric mucosa using unfixed cryostat section or incubation with aqueous solution of tritiated lafutidine, followed by in vitro autoradiography or autoradiography of soluble compounds. The localization of calcitonin gene-related peptide immunoreactivity was compared with the lafutidine binding sites. As a result, lafutidine-specific binding sites in the body of the fundic glands were accumulated on the parietal cells, while in the neck and base of the fundic glands, lafutidine was found to bind to the CGRP immunoreactive nerves. In the human fundic mucosa, the lafutidine bindings were also observed on the enteric nerves as well as the parietal cells. In conclusion, autoradiographic studies have shown that lafutidine effector sites coincided with the CGRP-immunoreactive nerves as well as the parietal cells.     

Gastric Inflammation During Systemic Anaphylaxis (Neutrophil Recruitment in Stomach Wall of Mice Does Not Require Mast Cell Participation)

We determined whether neutrophil infiltrationinto the stomach wall occurred during systemicanaphylaxis in mice and assessed the participation ofmast cells in the response. Normal mice sensitized and challenged with antigen exhibited significantneutrophil infiltration in the gastric mucosa andsubmucosa compared with saline-challenged mice. Thedevelopment of clinical signs of anaphylaxis and extent of gastric neutrophil infiltration was similarin mast cell-deficient Kit^W/Kit^W-vor Mgf^Sl/Mgf^Sl-d mice and therespective normal congenic mice. Pretreatment withsodium cromoglycate prevented the clinical signs of anaphylaxis and significantlydiminished the infiltration of neutrophils in +/+ orKit^W/Kit^W-v mice. Systemicanaphylaxis is associated with neutrophil infiltrationinto the stomach wall in mice, and mast cells are not required for thedevelopment of either the clinical manifestations orgastric neutrophil infiltration observed in theresponse.