Injection of irradiated b16 melanoma genetically-modified to secrete IFN-alpha causes regression of an established tumor

Highly aggressive murine B16 melanoma was engineered to secrete IFN-alpha constitutively. Cells expressing IFN-alpha were injected into syngeneic C57BL/6 mice and the mice were monitored for tumor development. Secretion of IFN-alpha by B16 melanoma cells completely abrogated their tumorigenicity in syngeneic mice. LFN-alpha-secreting cells also abrogated the tumorigenicity of IFN-gamma-secreting and TNF-alpha-secreting cells when injected in combination whereas cells secreting either IFN-gamma or TNF-alpha grow progressively in mice when injected alone. Moreover, protected animals developed significant immunity against subsequent challenge with parental cells. Injection of parental cells and IFN-alpha-secreting cells together in a mixed tumor transplantation assay resulted in a significant reduction of tumorigenicity of the parental cells. Histopathological studies of the tissues from the injection site of the mice inoculated with a combination of parental and B16.IFN-alpha cells revealed the existence of a massive cellular infiltrate composed of lymphocytes and granulocytes at an early stage (7-11 days). In the later stages (22 days), no recognizable tumor tissue was detected. Injection of irradiated IFN-alpha-secreting cells in the mice carrying an established tumor completely prevented tumor development in 80% of the treated mice when injection was performed on the same side as the tumors. Injection of irradiated IFN-alpha-secreting cells in the contralateral site showed much less effect on the established tumor. Systemic antitumor effects on the established tumor can be enhanced by using a combination of irradiated IFN-alpha and IFN-gamma secreting cells as a vaccinating inoculum.     

Foamy gland pattern of pancreatic ductal adenocarcinoma: a deceptively benign-appearing variant

Pathologic diagnosis of pancreatic adenocarcinoma is frequently a challenge, particularly in small biopsies, frozen sections, and in metastatic foci. Here we report a deceptively benign-appearing and morphologically distinctive pattern of ductal adenocarcinoma with prominent microvesicular cytoplasm, giving the cells a foamy appearance similar to that described in the prostate (Am J Surg Pathol 1996;20:419). This variant, which we refer to as foamy gland pattern (FGP), was frequently misdiagnosed in frozen sections or biopsies and its pathologic stage underestimated in surgical specimens. Histologically, the diagnostic features were: (1) white and crisply foamy, "microvesicular" cytoplasm; (2) often basally located and compressed, hyperchromatic nuclei reminiscent of endocervical glands (and so-called "adenoma malignum") or gastric foveolar glands; (3) irregular nuclear contours forming wrinkled (raisinoid) nuclei in some areas; and (4) a distinctive chromophilic condensation of the cytoplasmic material in the luminal aspect of the cells forming a brush border-like zone (BLZ). Histochemically, this BLZ was positive for mucicarmine, alcian blue, and high iron diamine, but not PAS. The remainder of the cytoplasm was negative for all these stains. In contrast, benign mucinous ducts, which constitute the major differential diagnosis, had more homogeneous acidophilic cytoplasm, lacked BLZ, and showed cytoplasmic staining with PAS. Immunohistochemically, the tumor cells were diffusely and strongly positive for CEA and cytokeratin 8 whereas B72.3 staining was focal and weak. MUC1 staining was largely confined to the BLZ. MUC2 was negative. P53 staining was detected in 16 of the 20 cases studied and was strong and diffuse in five. K-ras mutation was detected in 6 of 8 cases studied. The clinical findings in the 20 patients in this study (4 pure and 16 mixed with usual ductal carcinoma) did not appear to differ significantly from those of ordinary ductal adenocarcinoma of the pancreas. Eleven patients were men and nine were women; the mean age was 62 years and the mean tumor size was 4.4 cm. Follow-up information was available in 17 patients of whom 7 were alive at an average follow up of 23 months (range, 7-104 mos), and 10 were dead of disease at a median follow up of 15 months (range, 4-42 mos). The median survival of the four patients with pure FGP was 18 months. The median survival did not appear to be significantly longer than that of the patients with resectable ordinary ductal adenocarcinoma in the authors' experience (109 patients, median survival of 12 mos, p = 0.48). In conclusion, foamy gland pattern of invasive pancreatic ductal carcinoma is morphologically distinctive and is prone to misdiagnosis as a benign process. The pathologic stage is often underestimated as a result of the lack of its recognition and misinterpretation as mucinous ducts. Careful attention to its microscopic features is adequate for accurate diagnosis. Histochemical and immunohistochemical stains are useful in confirming the diagnosis of malignancy in challenging cases.     

A prospective study of the correlation between genital pathogens and morbidity following diathermy loop excision of the transformation zone.

A prospective study of 48 women was carried out to estimate the incidence of common genital pathogens in women referred to colposcopy clinic requiring diathermy loop excision and to compare patient morbidity in the subgroups with and without genital pathogens. Of the 43 women included in the analysis, genital pathogens were present in 24 cases (56%) and absent in 19 (44%) of the 24 positive cases, 19 (79%) women had pathogen(s) on the cervical swab, 24 (100%) had pathogen(s) on the high vaginal swab and 15 (63%) had both a positive cervical and high vaginal swab (HVS). The most frequently isolated groups of organisms were mixed anaerobes, alone (four HVS and four cervical) or in combination with Gardnerella vaginalis (four HVS and three cervical) or coliforms (two HVS and two cervical). The mean duration of bleeding and vaginal discharge in the two study groups was not statistically significant (t value 1.97, P 0.05; and t value 0.48, P 0.5, respectively). However, the mean duration of bleeding graded by the patient as being moderate to severe was significantly different in the two groups (t value 3.18 P 0.01). Fifty-six per cent of the women in the study had confirmed genital pathogens, predominantly anaerobes, and the prolonged moderate-to-severe bleeding in this group suggests a potential role for prophylactic bacteriocides, although the study size was unable to implicate a single pathogen.     

Dibenzo[a,l]pyrene-induced DNA adduction, tumorigenicity, and Ki-ras oncogene mutations in strain A/J mouse lung

Dibenzo[a,l]pyrene (DB[a,l]P), an environmental polycyclic aromatic hydrocarbon, is the most potent carcinogen ever tested in mouse skin and rat mammary gland. In this study, DB[a,l]P was examined for DNA adduction, tumorigenicity, and induction of Ki-ras oncogene mutations in tumor DNA in strain A/J mouse lung. Groups of mice received a single i.p. injection of 0.3, 1.5, 3.0, or 6.0 mg/kg DB[a,l]P in tricaprylin. Following treatment, DNA adducts were measured at times between 1 and 28 days, while tumors were counted at 250 days and analyzed for the occurrence of point mutations in codons 12 and 61 of the Ki-ras oncogene. DB[a,l]P in strain A/J mouse lung induced six major and four minor DNA adducts. Maximal levels of adduction occurred between 5 and 10 days after injection followed by a gradual decrease. DB[a,l]P-DNA adducts in lung tissue were derived from both anti- and syn-11,12- dihydroxy-13,14-epoxy- 11,12,13,14-tetrahydrodibenzo[a,l]pyrene (DB[a,l]PDE) and both deoxyadenosine (dAdo) and deoxyguanosine (dGuo) residues in DNA as revealed by cochromatography. The major adduct was identified as a product of the reaction of an anti-DB[a,l]PDE with dAdo in DNA. DB[a,l]P induced significant numbers of lung adenomas in a dose- dependent manner, with the highest dose (6.0 mg/kg) yielding 16.1 adenomas/mouse. In tricaprylin-treated control animals, there were 0.67 adenomas/mouse. Based on the administered dose, DB[a,l]P was more active than other environmental carcinogens including benzo[a]pyrene. As a function of time-integrated DNA adduct levels, DB[a,l]P induced lung adenomas with about the same potency as other PAHs, suggesting that the adducts formed by DB[a,l]P are similar in carcinogenic potency to other PAHs in the strain A/J mouse lung model. Analysis of the Ki- ras mutation spectrum in DB[a,l]P-induced lung tumors revealed the predominant mutations to be G-->T transversions in the first base of codon 12, A-->G transitions in the second base of codon 12, and A-->T transversions in the second or third base of codon 61, concordant with the DNA adduct profile.      

Management of leg ulcers

Leg ulcer is a leading cause of morbidity among older subjects, especially women in the Western world. About 400 years BC, Hippocrates wrote, "In case of an ulcer, it is not expedient to stand, especially if the ulcer be situated on the leg". Hippocrates himself had a leg ulcer. The best treatment of any leg ulcer depends upon the accurate diagnosis and the underlying aetiology. The majority of leg ulcers are due to venous disease and/or arterial disease, but the treatment of the underlying cause is far more important than the choice of dressing. The aetiology, pathogenesis, treatment, and the future trends in the management of the leg ulcers are discussed in this review.     

TREATMENT OF PALMOPLANTER HYPERHIDROSIS BY IONTOPHORESIS

Twenty-seven patients with idiopathic palmoplanter hyperhidrosis were treated with Iontotherapy over a one year period. In twenty-four cases there was a good response but maintenance therapy was required every 3-4 weeks.KEY WORDS: Iontophoresis, Palmoplanter hyperhidrosis