Silica-induced Chronic Inflammation Promotes Lung Carcinogenesis in the Context of an Immunosuppressive Microenvironment

The association between inflammation and lung tumor development has been clearly demonstrated. However, little is known concerning the molecular events preceding the development of lung cancer. In this study, we characterize a chemically induced lung cancer mouse model in which lung cancer developed in the presence of silicotic chronic inflammation. Silica-induced lung inflammation increased the incidence and multiplicity of lung cancer in mice treated with N-nitrosodimethylamine, a carcinogen found in tobacco smoke. Histologic and molecular analysis revealed that concomitant chronic inflammation contributed to lung tumorigenesis through induction of preneoplastic changes in lung epithelial cells. In addition, silica-mediated inflammation generated an immunosuppressive microenvironment in which we observed increased expression of programmed cell death protein 1 (PD-1), transforming growth factor-β1, monocyte chemotactic protein 1 (MCP-1), lymphocyte-activation gene 3 (LAG3), and forkhead box P3 (FOXP3), as well as the presence of regulatory T cells. Finally, the K-RAS mutational profile of the tumors changed from Q61R to G12D mutations in the inflammatory milieu. In summary, we describe some of the early molecular changes associated to lung carcinogenesis in a chronic inflammatory microenvironment and provide novel information concerning the mechanisms underlying the formation and the fate of preneoplastic lesions in the silicotic lung.     

Prolonged Clinical Benefit of Everolimus Therapy in the Management of High-Grade Pancreatic Neuroendocrine Carcinoma

Treatment options for patients with high-grade pancreatic neuroendocrine tumors (pNET) are limited, especially for those with progressive disease and for those who experience treatment failure. Everolimus, an oral inhibitor of mammalian target of rapamycin (mTOR), has been approved for the treatment of patients with low- or intermediate-grade advanced pNET. In the randomized phase III RADIANT-3 study in patients with low- or intermediate-grade advanced pNET, everolimus significantly increased progression-free survival (PFS) and decreased the relative risk for disease progression by 65% over placebo. This case report describes a heavily pretreated patient with high-grade pNET and liver and peritoneal metastases who achieved prolonged PFS, clinically relevant partial radiologic tumor response, and resolution of constitutional symptoms with improvement in Karnofsky performance status while receiving a combination of everolimus and octreotide long-acting repeatable (LAR). Radiologic and clinical responses were maintained for 19 months, with minimal toxicity over the course of treatment. This case supports the findings that the combination of everolimus plus octreotide LAR may be considered for use in patients with high-grade pNET and progressive disease. Although behavior and aggressiveness are different between low- or intermediate-grade and high-grade pNET, some high-grade pNET may express mTOR; hence, everolimus should be considered in a clinical trial.Key words: Neuroendocrine tumors, Pancreatic, Everolimus, Octreotide long-acting repeatable     

Aspiration and characterization of predentin fluid in developing rat teeth by means of a micropuncture and micro-analytical technique

A fluid phase was aspirated in vivo and in vitro from predentin or pulp of developing rat teeth by means of a micropuncture technique. Pooled aspirates (approx. 2 nL) were analyzed for P, Na, K, Ca, Mg, and S by electron probe microtechniques (Lechene and Warner, 1979). Compared with pulp fluid, currently and previously studied cartilage fluids, as well as serum, predentin fluid showed elevated K, depressed Na, Cl, and Ca, as well as increased P. Statistical analysis was possible for only a few groups of comparisons among the elemental profiles. Ultrastructural examination of the aspiration site and of the aspirates showed no evidence of contamination with cell organelles or other formed elements. The micropuncture technique used was a critically precise and laborious procedure; possible contamination with intracellular fluid could not be avoided. The consistently low Mg concentration found in the aspirates, however, supports our view that the samples were primarily extracellular.     

Treatment of intrabony defects with enamel matrix proteins or barrier membranes: results from a multicenter practice-based clinical trial

BACKGROUND: This prospective multicenter, randomized, controlled clinical trial compared the clinical outcomes of enamel matrix proteins (EMD) versus placement of a bioabsorbable membrane in conjunction with guided tissue regeneration (GTR). METHODS: Seventy-five patients with advanced chronic periodontitis were recruited in seven centers in three countries. All patients had at least one intrabony defect of > or = 3 mm. Heavy smokers (> or = 20 cigarettes/day) were excluded. The surgical procedures included access for root instrumentation using the simplified papilla preservation flap and either the application of EMD or the placement of a GTR membrane. At baseline and 1 year following the interventions, clinical attachment levels (CAL), probing depths (PD), recession (REC), full-mouth plaque scores, and full-mouth bleeding scores were assessed. A total of 67 patients completed the study. RESULTS: At 1 year, the EMD defects gained 3.1 +/- 1.8 mm of CAL, versus 2.5 +/- 1.9 mm for GTR defects. Probing depth reduction was 3.8 +/- 1.5 mm and 3.3 +/- 1.5 mm, respectively. A multivariate analysis indicated that the differences between EMD and GTR treatments were not significant while a center effect and baseline PD significantly influenced CAL gains. No significant differences in terms of frequency distribution of the outcomes were observed. All cases treated with GTR presented at least one surgical complication, mostly membrane exposure, while only 6% of EMD treated sites displayed complications (P < 0.0001). CONCLUSIONS: The results of this trial failed to demonstrate superiority of one treatment modality over the other. GTR outcomes in this trial were lower than anticipated based on previous evidence. This was attributed to the high prevalence of post-surgical complications in the GTR group.     

Lack of association of MTHFR rs1801133 polymorphism and CTCFL mutations with sperm methylation errors in infertile patients

Purpose

To find out whether the MTHFR rs1801133 polymorphism is a risk factor for male infertility in the Spanish population. To determine if a pattern of sperm DNA hypomethylation at the paternally imprinted loci H19-ICR and/or IG-DMR is related to the MTHFR rs1801133 polymorphism and/or CTCFL mutations.

Methods

One hundred and seven samples from individuals who sought consultation for fertility problems and twenty-five semen samples from sperm donors were analyzed. The MTHFR rs1801133 SNP was analyzed in all samples by the PCR-RFLP method. We compared the distribution of the genotypes between control and infertile populations and among the groups of patients with altered seminal parameters. In those patients with the most severe hypomethylation pattern (n = 12) we also analyzed the CTCFL protein-coding exons by sequencing.

Results

There were no significant differences in the distribution of the genotypes among the control and infertile populations. Moreover, none of the genotypes were associated, neither to the characteristics of the seminogram, nor to the presence of sperm DNA hypomethylation. We did not identify frameshift, nonsense or missense mutations of the CTCFL gene.

Conclusions

The MTHFR rs1801133 polymorphism is not associated with male infertility in the Spanish population. Neither the MTHFR polymorphism, nor CTCFL mutations explain a pattern of sperm hypomethylation at paternally imprinting loci.

Electronic supplementary material

The online version of this article (doi:10.1007/s10815-013-0013-2) contains supplementary material, which is available to authorized users.     

Erythema nodosum associated with sporotrichosis

Case 1 A 34‐year‐old woman had ulcerated lesion 2 cm in diameter on the right leg of 2 months’ evolution. She also presented painful erythematous nodules on lower limbs accompanied by arthralgia appearing 1 month after the initial lesion ( Figure 1a ). The patient reported having been scratched on the right leg by a cat with sporotrichosis 15 days before the initial symptoms. Examination of the ulcerated lesion showed growth of Sporothrix schenckii, and histological investigation of one nodule showed a mononuclear inflammatory infiltrate in the hypodermis with a predominantly septal distribution, negative upon culture for fungi ( Figure 1b ). Radiographic examination of left ankle showed increased soft tissue, while other ancillary tests were normal. The patient was treated with itraconazole 100 mg/day for 4 months, with regression of Erythema nodosum (EN) on day 20.

Figure Figure 1  Open in figure viewer PowerPoint (a) Ulcerated lesions on right calf and erythematous nodules on lower limbs. (b) Histopathology of one lower limbs nodule, displaying small granuloma in the subcutaneous cellular tissue (HE, 4 ×)     

Attachment of Treponema pallidum to fibronectin, laminin, collagen IV, and collagen I, and blockage of attachment by immune rabbit IgG.

As shown by scanning electron and phase contrast microscopy, Treponema pallidum attached in vitro to basement membranes purified from kidney cortex tissues or from retinal vessels. This organism also attached to the extracellular matrix remaining after cultured cells had been solubilised with Triton X. Fibronectin, laminin, collagen, IV, collagen I, and hyaluronic acid are structural components of basement membranes and extracellular matrices. Experiments were performed to investigate the in vitro attachment of T pallidum to each of these components. Viable or heat inactivated treponemes were added to glass coverslips precoated with different concentrations of each component. After various times of incubation, coverslips were washed and the attached organisms were counted. Large numbers of viable organisms attached to each of these five components. In contrast, heat inactivation sharply reduced numbers of attached organisms. The IgG fractions of immune and non-immune rabbit serum samples were affinity purified using protein A. T pallidum was preincubated with both fractions, then incubated with either intact cultured cells or with coverslips coated with the five tissue components. The IgG from immune serum blocked treponemal attachment to the cultured cells and to fibronectin, laminin, collagen IV, and collagen I, but not to hyaluronic acid. These results are discussed in terms of attachment mechanisms of T pallidum and potential applications to in vivo infection.     

American tegumentary leishmaniasis - a case of therapeutic challenge

American Tegumentary Leishmaniasis (ATL) is a chronic, non-contagious, infectious disease affecting millions of people worldwide. The timely and proper treatment is of great importance to prevent the disease from progressing to destructive and severe forms. Treatment for ATL recommended by the Brazilian Ministry of Health is similar for the whole country, regardless of the species of Leishmania. It is known that the response to treatment may vary with the strain of the parasite, the immune status of the patient and clinical form. We report the case of a healthy patient, coming from Manaus, Amazonas state, Brazil, who presented resistance to treatment with N-methyl-glutamine and liposomal amphotericin B, only being healed after using pentamidine.