Molecular and functional anticancer effects of GLP/G9a inhibition by UNC0646 in MeWo melanoma cells

In recent years, histone methyltransferases (HMTs) have emerged as important therapeutic targets in cancer due to their oncogenic role. Herein, we used the GLP/G9a inhibitor UNC0646 to assess whether the inhibition of such HMTs could induce cell death in MeWo melanoma cells. Furthermore, we investigated the cellular and molecular mechanisms involved in the observed cell death events. Finally, we performed a functional genomics analysis of 480 melanoma samples to characterize G9a/GLP involvement in melanoma. Interestingly, after UNC0646 treatment, MeWo cells underwent apoptosis, followed by loss of mitochondrial membrane potential and the generation of reactive oxygen species (ROS). Furthermore, MeWo cells treated with UNC0646 showed cell cycle arrest and inhibition of proliferation. At the molecular level, UNC0646 treatment increased the transcriptional levels of CDK1 and BAX, and decreased BCL-2 mRNA levels. Finally, we performed a functional enrichment analysis, which demonstrated that dozens of biological pathways were enriched in melanoma samples according to GLP and G9a expression, including apoptosis and necrosis. Taken together, our data show that inhibition of GLP/G9a using UNC0646 exerts anticancer effects on melanoma cells by controlling their proliferation and inducing apoptosis.

Anatomical and histochemical characterization of stem and leaves of Bauhinia pulchella Benth. (Fabaceae)

Bauhinia pulchella Benth. (Fabaceae), is native to Brazil and popularly known as pata-de-bode. In folk medicine, it is used to treat diabetes. Pharmacological studies have demonstrated different properties, such as cytotoxic and antioxidant, and different chemical constituents, such as essential oil, triterpenoids, steroids, among others. In order to highlight the morphological differences of the species B. pulchella from the others of the genus, and its pharmacological potential, the present study aimed to carry out the anatomical and histochemical characterization of the stem and leaves of B. pulchella. Usual methods in plant anatomy were used in the preparation of semi-permanent slides containing cross sections of the stem, petiole and leaf blade and paradermal sections of the leaf blade for analysis in light microscopy and polarized light. Histochemical tests were also performed to localize the metabolites in the stem and leaf blade. The stem of B. pulchella has a cylindrical outline, the bark is composed of 7-8 layers of cells and discontinuously distributed sclerenchyma; petiole presents flat convex contour, prominences in the adaxial region, concentric amphicrivral vascular bundle, surrounding a small concentric anfivasal intramedullary bundle, adaxially two accessory bundles and tector trichomes; leaf blade with anisocytic and tetracytic stomata on the adaxial surface and anisocytic, tetracytic and anomocytic on the abaxial surface; and midrib with plain-convex outline, 1-2 layers of collenchyma and covering trichomes. Characteristics that differ from other species of the genus Bauhinia. Alkaloids, phenolic compounds, lipophilic compounds, lignin, triterpenes, steroids and tannins were observed in the species. The results are fundamental for the pharmacobotanical standardization of the studied species.

Uncovering the effects of Giardia duodenalis on the balance of DNA viruses and bacteria in children's gut microbiota

The neglected parasitosis giardiasis is one of the most common intestinal infections worldwide, affecting mainly infants and young children. Giardia duodenalis may disturb the local microbiome, leading to intestinal ecosystem disorders, and altering different processes in the host, such as the immune response. Nevertheless, the alterations promoted by G. duodenalis on the human gut microbiome have not been thoroughly investigated. Here, we characterized the gut microbiota of G. duodenalis-infected children and determine the main alterations promoted by the parasite. To do so, fecal samples of 26 infected and four uninfected children aged 2 to 6 years old were processed for High Efficiency Microarray analysis, in order to describe their bacterial and viral profiles. Then, we quantified the total bacterial population by qPCR and assessed fecal calprotectin levels, which are closely related with gut inflammation. A total of 286 bacteria's species and 17 viruses' strains were identified. Our results revealed no statistically significant differences between G. duodenalis positive and negative groups in the taxa's phyla and families. However, bacterial species diversity was increased in children infected with G. duodenalis (p < 0.05), while the total number of bacteria was decreased (p < 0.05). Considering the virome analysis, 17 different strains were identified, 88% being bacteriophages. The correlation analysis revealed an important disruption in the balance of DNA virus and bacteria within the intestinal microbiota of Giardia-positive children. Our findings constitute the first description of the gut virome of Giardia-infected children and suggest that G. duodenalis infection exerts a modulatory effect on the gut microbiome, promoting local inflammation and altering the equilibrium of the parasite-microbiota-host triad. This highlights the importance of considering polymicrobial associations and understanding the broader context of giardiasis. Overall, our study provides new insights into the complex interactions between intestinal parasites and the microbiota, which may have implications for the development of novel therapeutic interventions in the future.

A systematic review on the cost-effectiveness assessment of tisagenlecleucel for refractory or relapsing B-cell acute lymphoblastic leukemia (R/R B-ALL) treatment in children and young adults

BACKGROUND AIMS

The advanced therapy product tisagenlecleucel is a CD19-directed genetically modified autologous T-cell immunotherapy that has brought hope for children and young adults with relapsed/refractory (R/R) B-cell acute lymphoblastic leukemia (B-ALL). We sought to evaluate the cost-effectiveness of tisagenlecleucel compared with conventional salvage therapies in pediatric and young adult patients with R/R B-ALL.

METHODS

This systematic review followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses parameters as registered in International Prospective Register of Systematic Reviews (CRD42021266998). Literature was searched using the MEDLINE databases via PubMed, EMBASE, Lilacs, the Cochrane Central Register of Controlled Trials and Web of Science in January 2022. Titles were screened independently by two reviewers. Articles deemed to meet the inclusion criteria were screened independently on abstract, and full texts were reviewed.

RESULTS

In total, 5627 publications were identified, from which six eligible studies were selected. The conventional therapies identified were blinatumomab (Blina), clofarabine monotherapy (Clo-M), clofarabine combined with cyclophosphamide and etoposide (Clo-C) and the combination of fludarabine, cytarabine and idarubicin (FLA-IDA). The discounted incremental cost-effectiveness ratio (ICER) per quality-adjusted life year (QALY) gained for tisagenlecleucel compared with Clo-C and Blina averages was $38 837 and $25 569, respectively. In relation to the cost of the drug, the average of tisagenlecleucel was approximately 4.3 times, 10.8 times or 4.7 times greater than the Clo-M, Clo-C and Blina, respectively.

CONCLUSIONS

This systematic review highlighted that tisagenlecleucel is a much more expensive therapy than conventional alternatives. However, tisagenlecleucel performed well on the ICER, not exceeding $100 000/QALY. It was also found that the advanced therapy product was more effective than the conventional small molecule and biological drugs, in terms of life years and QALY gained.

The Combination of Synoeca-MP Antimicrobial Peptide with IDR-1018 Stimulates Proliferation, Migration, and the Expression of Pro-Regenerative Genes in Both Human Skin Cell Cultures and 3D Skin Equivalents

In skin lesions, the development of microbial infection affects the healing process, increasing morbidity and mortality rates in patients with severe burns, diabetic foot, and other types of skin injuries. Synoeca-MP is an antimicrobial peptide (AMP) that exhibits activity against several bacteria of clinical importance, but its cytotoxicity can represent a problem for its positioning as an effective antimicrobial compound. In contrast, the immunomodulatory peptide IDR-1018 presents low toxicity and a wide regenerative potential due to its ability to reduce apoptotic mRNA expression and promote skin cell proliferation. In the present study, we used human skin cells and a 3D skin equivalent models to analyze the potential of the IDR-1018 peptide to attenuate the cytotoxicity of synoeca-MP, as well as the influence of synoeca-MP/IDR-1018 combination on cell proliferation, regenerative processes, and wound repair. We found that the addition of IDR-1018 significantly improved the biological properties of synoeca-MP on skin cells without modifying its antibacterial activity against S. aureus. Likewise, in both melanocytes and keratinocytes, the treatment with synoeca-MP/IDR-1018 combination induces cell proliferation and migration, while in a 3D human skin equivalent model, it can accelerate wound reepithelization. Furthermore, treatment with this peptide combination generates an up-regulation in the expression of pro-regenerative genes in both monolayer cell cultures and in 3D skin equivalents. This data suggests that the synoeca-MP/IDR-1018 combination possesses a good profile of antimicrobial and pro-regenerative activity, opening the door to the development of new strategies for the treatment of skin lesions.

Extracellular vesicles in the context of Chagas Disease - A systematic review

Extracellular vesicle (EVs) traffic is considered an important cellular communication process between cells that can be part of a single organism or belong to different living beings. The relevance of EV-mediated cellular communication is increasingly studied and appreciated, especially in relation to pathological conditions, including parasitic disorders, in which the EV release and uptake processes have been documented. In the context of Chagas Disease (CD), EVs have been explored, however, current data have not been systematically revised in order to provide an overview of the published literature and the main results obtained thus far. In this systematic review, 25 studies involving the investigation of EVs in CD were identified. The studies involved Trypanosoma cruzi (Tc)-derived EVs (Tc-EVs), as well as EVs derived from T. cruzi-infected mammalian cells-derived EVs, mainly isolated by ultracentrifugation and poorly characterized. The objectives of the identified studies included the characterization of the protein and RNA cargo of Tc-EVs, as well as investigation of EVs in parasitic infections and immune-related processes. Overall, our systematic review reveals that EVs play critical roles in several mechanisms related to the interaction between T. cruzi and mammalian hosts, their contribution to immune system evasion by the parasite, and to chronic inflammation in the host. Future studies will benefit from the consolidation of isolation and characterization methods, as well as the elucidation of the role of EVs in CD.

Differential peripheral blood mononuclear cell reactivity against SARS-CoV-2 proteins in naïve and previously infected subjects following COVID-19 vaccination

The decline in vaccine efficacy and the risk of reinfection by SARS-CoV-2 make new studies important to better characterize the immune response against the virus and its components. Here, we investigated the pattern of activation of T-cells and the expression of inflammatory factors by PBMCs obtained from naïve and previously infected subjects following COVID-19 vaccination, after PBMCs stimulation with S1, RBD, and N-RBD SARS-CoV-2 proteins. PBMCs showed low levels of ACE2 and TMPRSS2 transcripts, which were not modulated by the exposure of these cells to SARS-CoV-2 proteins. Compared to S1 and RBD, N-RBD stimulation showed a greater ability to stimulate T-cell reactivity, according to CD25 and CD69 markers. Interestingly, T-cell reactivity was more pronounced in vaccinated subjects with prior SARS-CoV-2 infection than in vaccinated donors who never had been diagnosed with COVID-19. Finally, N-RBD stimulation promoted greater expression of IL-6 and IFN-γ in PBMCs, which reinforces the greater immunogenic potential of this protein in the vaccinated subjects. These data suggest that PBMCs from previously infected and vaccinated subjects are more reactive than those derived from just vaccinated donors. Moreover, the N-RBD together viral proteins showed a greater stimulatory capacity than S1 and RBD viral proteins.

Multiparametric analysis of host and parasite elements in new world tegumentary leishmaniasis

Tegumentary leishmaniasis is a tropical disease caused by protozoa of the genus Leishmania. Clinically, the disease presents a broad spectrum of symptoms, the mechanisms underlying the development of lesions remaining to be fully elucidated. In the present work, we performed a correlation and multiparametric analysis to evaluate how parasite- and host-related aspects associate with each other, and with the different clinical manifestations of tegumentary leishmaniasis. This cross-sectional study involved 75 individuals from endemic areas of Brazil, grouped according to their symptoms. Leishmania species were determined by DNA sequencing, and parasite load, antibody production, and cytokine profile were evaluated by kDNA qPCR, ELISA, and flow cytometry. Data were analyzed using the Chi-square test, principal component analysis, canonical discriminant analysis, and correlation analysis. Among the recruited patients, 23 (31%) were asymptomatic, 34 (45%) had primary cutaneous leishmaniasis, 10 (13%) presented recurrent cutaneous leishmaniasis, and eight (11%) had mucocutaneous leishmaniasis. Leishmania species identified included L. amazonensis, L. braziliensis, and L. guyanensis. Surprisingly, no Leishmania RNA virus infection was detected in any sample. In summary, our work showed that parasite load, antibody production, and cytokine levels alone are not determinants for tegumentary leishmaniasis symptoms. However, the correlation analysis allowed us to observe how these factors are correlated to each other within the groups, which revealed a unique network for each clinical manifestation. Our work reinforces the complexity of tegumentary leishmaniasis outcomes - which are associated with multiple host and parasite-related elements and provides a holistic model of the disease.

Nanostructured lipid carriers loaded with an association of minoxidil and latanoprost for targeted topical therapy of alopecia

Alopecia is a condition associated with different etiologies, ranging from hormonal changes to chemotherapy, that affects over 80 million people in the USA. Nevertheless, there are currently few FDA-approved drugs for topical treatment, and existing formulations still present skin irritation issues, compromising treatment adherence. This work aimed to develop a safe formulation based on nanostructured lipid carriers (NLC) that entrap an association of minoxidil and latanoprost and target drug delivery to the hair follicles. To do so, thermal techniques combined with FTIR were used to assess the chemical compatibility of the proposed drug association. Then, NLC with 393.5 ± 36.0 nm (PdI<0.4) and +22.5 ± 0.2 mV zeta potential were produced and shown to entrap 86.9% of minoxidil and 99.9% of latanoprost efficiently. In vitro, the free drug combination was indicated to exert positive effects over human primary epidermal keratinocytes, supporting cell proliferation, migration and inducing the mRNA expression of MKI67 proliferation marker and VEGF - a possible effector for minoxidil-mediated hair growth. Interestingly, such a favorable drug combination profile was optimized when delivered using our NLC. Furthermore, according to the HET-CAM and reconstructed human epidermis assays, the nanoformulation was well tolerated. Finally, drug penetration was evaluated in vitro using porcine skin. Such experiments indicated that the NLC could be deposited preferentially into the hair follicles, causing a considerable increase in the penetration of the two drugs in such structures, compared to the control (composed of the free compounds) and generating a target-effect of approximately 50% for both drugs. In summary, present results suggest that hair follicle-targeted delivery of the minoxidil and latanoprost combination is a promising alternative to treat alopecia.

Skin Regenerative Potential of Cupuaçu Seed Extract (Theobroma grandiflorum), a Native Fruit from the Amazon: Development of a Topical Formulation Based on Chitosan-Coated Nanocapsules

Scarless skin regeneration is a challenge in regenerative medicine. Herein, we explore the regenerative potential of a Cupuaçu seed extract (Theobroma grandiflorum) to develop an innovative skin regeneration formulation based on chitosan-coated nanocapsules. Cupuaçu seed extract significantly stimulated cell proliferation and migration. A reparative gene expression profile could be verified following extract treatment, which included high levels of MKI67, a cellular proliferation marker, and extracellular matrix genes, such as ELN and HAS2, which code for elastin and hyaluronic acid synthase 2. Formulations with Cupuaçu seed extract successfully entrapped into nanocapsules (EE% > 94%) were developed. Uncoated or coated nanocapsules with low-molecular-weight chitosan presented unimodal size distribution with hydrodynamic diameters of 278.3 ± 5.0 nm (PDI = 0.18 ± 0.02) and 337.2 ± 2.1 nm (PDI = 0.27 ± 0.01), respectively. Both nanosystems were physically stable for at least 120 days and showed to be non-irritating to reconstructed human epidermis. Chitosan coating promoted active penetration into undamaged skin areas, which were still covered by the stratum corneum. In conclusion, the present study demonstrated for the first time the biotechnological potential of the frequently discarded Cupuaçu seed as a valuable pharmaceutical ingredient to be used in regenerative skin products.

Dissecting the relationship between antimicrobial peptides and mesenchymal stem cells

Among the various biological properties presented by Mesenchymal Stem Cells (MSCs), their ability to control the immune response and fight pathogen infection through the production of antimicrobial peptides (AMPs) have been the subject of intense research in recent years. AMPs secreted by MSCs exhibit activity against a wide range of microorganisms, including bacteria, fungi, yeasts, and viruses. The main AMPs produced by these cells are hepcidin, cathelicidin LL-37, and β-defensin-2. In addition to acting against pathogens, those AMPs have also been shown to interact with MSCs to modulate MSC proliferation, migration, and regeneration, indicating that such peptides exert a more diverse biological effect than initially thought. In the present review, we discuss the production of AMPs by MSCs, revise the multiple functions of these peptides, including their influence over MSCs, and present an overview of clinical situations in which the antimicrobial properties of MSCs may be explored for therapy. Finally, we discuss possibilities of combining MSCs and AMPs to generate improved therapeutic strategies.

The MAPKinase Signaling and the Stimulatory Protein-1 (Sp1) Transcription Factor Are Involved in the Phototherapy Effect on Cytokines Secretion from Human Bronchial Epithelial Cells Stimulated with Cigarette Smoke Extract

The present study was aimed to investigate the phototherapy effect with low-level laser on human bronchial epithelial cells activated by cigarette smoke extract (CSE). Phototherapy has been reported to actuate positively for controlling the generation/release of anti-inflammatory and pro-inflammatory mediators from different cellular type activated by distinct stimuli. It is not known whether the IL-8 and IL-10 release from CSE-stimulated human bronchial epithelium (BEAS) cells can be influenced by phototherapy. Human bronchial epithelial cell (BEAS) line was cultured in a medium with CSE and irradiated (660 nm) at 9 J. Apoptosis index was standardized with Annexin V and the cellular viability was evaluated by MTT. IL-8, IL-10, cAMP, and NF-κB were measured by ELISA as well as the Sp1, JNK, ERK1/2, and p38MAPK. Phototherapy effect was studied in the presence of mithramycin or the inhibitors of JNK or ERK. The IL-8, cAMP, NF-κB, JNK, p38, and ERK1/2 were downregulated by phototherapy. Both the JNK and the ERK inhibitors potentiated the phototherapy effect on IL-8 as well as on cAMP secretion from BEAS. On the contrary, IL-10 and Sp1 were upregulated by phototherapy. The mithramycin blocked the phototherapy effect on IL-10. The results suggest that phototherapy has a dual effect on BEAS cells because it downregulates the IL-8 secretion by interfering with CSE-mediated signaling pathways, and oppositely upregulates the IL-10 secretion through of Sp1 transcription factor. The manuscript provides evidence that the phototherapy can interfere with MAPK signaling via cAMP in order to attenuate the IL-8 secretion from CSE-stimulated BEAS. In addition, the present study showed that phototherapy effect is driven to downregulation of the both the IL-8 and the ROS secretion and at the same time the upregulation of IL-10 secretion. Besides it, the increase of Sp-1 transcription factor was crucial for laser effect in upregulating the IL-10 secretion. The dexamethasone corticoid produces a significant inhibitory effect on IL-8 as well as ROS secretion, but on the other hand, the corticoid blocked the IL-10 secretion. Taking it into consideration, it is reasonable to suggest that the beneficial effect of laser therapy on lung diseases involves its action on unbalance between pro-inflammatory and anti-inflammatory mediators secreted by human bronchial epithelial cells through different signaling pathway.

Advanced Therapies and Regulatory Framework in Different Areas of the Globe: Past, Present, and Future

PURPOSE

The field of human medicine is in a constant state of evolution, developing and incorporating technological advances from diverse scientific fields. In recent years, cellular and gene therapies have come of age, challenging regulatory agencies to define the path for commercial registration. Approval necessarily demands robust evidence for safety and efficacy, but these exigencies must not be such that they render unviable the development and testing of the therapeutic agent. Furthermore, reimbursement strategies are required to guarantee commercial viability of these products, to avoid the risk that they will be removed from the market or become unavailable to most patients through lack of financial resources. To address such challenges, several countries have created strategies to manage advanced therapy products.

METHODS

Based on official documents published by regulatory agencies worldwide, this review summarizes the current scenario in the United States, Europe, Brazil, Japan, South Korea, and China in this regard, discussing the harmonized and dissonant aspects of the regulatory framework in different regions of the world and exploring perspectives for the future.

FINDINGS

The technical aspects of advanced therapies are increasingly complex, bringing challenges for high mass commercialization and demanding specific regulation. The regulatory framework of the analyzed regions is mainly recent and discordant, but many harmonizing initiatives were observed.

IMPLICATIONS

The comparative analysis of regulatory frameworks in different parts of the world is informative, as scientists must be aware of the rationale of regulators to assertively develop new technology and products that will be commercialized. The comparative analysis also provides insight into the main dissonances that must be addressed, fostering the harmonization of local regulatory frameworks. Many unanswered questions still lie ahead for the field of advanced therapies, and empirical evidence will be the most effective way to separate hype from hope and to establish the most sustainable mechanisms to regulate and finance such products in each part of the world.

Human Stem Cell-Derived Retinal Pigment Epithelial Cells as a Model for Drug Screening and Pre-Clinical Assays Compared to ARPE-19 Cell Line

Background and Objectives

Eye diseases have a high socioeconomic impact on society and may be one of the fields in which most stem cell-related scientific accomplishments have been achieved recently. In this context, human Pluripotent Stem Cell (hPSC) technology arises as an important tool to produce and study human Embryonic Stem cell derived-Retinal Pigmented Epithelial Cells (hES-RPE) for several applications, such as cell therapy, disease modeling, and drug screening. The use of this technology in pre-clinical phases attends to the overall population desire for animal-free product development. Here, we aimed to compare hES-RPE cells with ARPE-19, one of the most commonly used retinal pigmented epithelial immortalized cell lines.

Methods and Results

Functional, cellular and molecular data obtained suggest that hES-RPE cells more closely resembles native RPEs compared to ARPE-19. Furthermore, hES-RPE revealed an interesting robustness when cultured on human Bruch’s membrane explants and after exposure to Cyclosporine (CSA), Sirolimus (SRL), Tacrolimus (TAC), Leflunomide (LEF) and Teriflunomide (TER). On these conditions, hES-RPE cells were able to survive at higher drug concentrations, while ARPE-19 cell line was more susceptible to cell death.

Conclusions

Therefore, hES-RPEs seem to have the ability to incur a broader range of RPE functions than ARPE-19 and should be more thoroughly explored for drug screening.

Mesenchymal Stem Cells: A New Piece in the Puzzle of COVID-19 Treatment

COVID-19 is a disease characterized by a strong inflammatory response in severe cases, which fails to respond to corticosteroid therapy. In the context of the current COVID-19 outbreak and the critical information gaps regarding the disease, several different therapeutic strategies are under investigation, including the use of stem cells. In the present manuscript, we provide an analysis of the rationale underlying the application of stem cells to manage COVID-19, and also a comprehensive compendium of the 69 clinical trials underway worldwide aiming to investigate the application of stem cells to treat COVID-19. Even though data are still scarce, it is already possible to observe the protagonism of China in testing mesenchymal stem cells (MSCs) for COVID-19. Furthermore, it is possible to determine that current efforts focus on the use of multiple infusions of high numbers of stem cells and derived products, as well as to acknowledge the positive results obtained by independent groups who publicized the therapeutic benefits provided by such therapies in 51 COVID-19 patients. In such a rapid-paced field, up-to-date systematic studies and meta-analysis will aid the scientific community to separate hype from hope and offer an unbiased position to the society and governments.

Mechanisms of DNA repair in Trypanosoma cruzi: What do we know so far?

Trypanosoma cruzi is the etiological agent of Chagas Disease, which affects 6-7 million people worldwide. Since the early stages of infection and throughout its life cycle, the parasite is exposed to several genotoxic agents. Furthermore, DNA damage is also part of the mechanism of action of at least a few trypanocidal drugs, including Benznidazole. Thus, it is paramount for the parasite to count on an efficient DNA repair machinery to guarantee genome integrity and survival. The present work provides an up-to-date review of both the conserved and peculiar DNA repair mechanisms described in T. cruzi against oxidative stress, ultraviolet and ionizing radiation, DNA adduct-inducing agents, and Benznidazole. The comprehension of the DNA repair mechanisms of the parasite may shed light on the parasite evolution and possibly pave the way for the development of novel and more effective trypanocidal drugs.

In vitro models for investigation of the host-parasite interface - possible applications in acute Chagas disease

Chagas disease (CD), caused by Trypanosoma cruzi, is the main parasitic disease in the Western Hemisphere, with an increasing number of cases, especially in non-endemic regions. The disease is characterized by cardiomegaly and mega viscera, nevertheless, the clinical outcome is hard to predict, underscoring the need for further research into the pathophysiology of CD. Even though most basic and translational research involving CD is performed using in vivo models, in vitro models arise as an ethical, rapidly evolving, and physiologically relevant alternative for CD research. In the present review, we discuss the past and recent in vitro models available to study the host-parasite interface in cardiac and intestinal CD, critically analyzing the possibilities and limitations of state-of-the-art alternatives for the CD host-parasite investigation.

IDR-1018 induces cell proliferation, migration, and reparative gene expression in 2D culture and 3D human skin equivalents

Skin lesions are associated with functional/cosmetic problems for those afflicted. Scarless regeneration is a challenge, not limited to the skin, and focus of active investigation. Recently, the host defense peptide innate defense regulatory peptide 1018 (IDR-1018) has shown exciting regenerative properties. Nevertheless, literature regarding IDR-1018 regenerative potential is scarce and limited to animal models. Here, we evaluated the regenerative potential of IDR-1018 using human 2D and 3D human skin equivalents. First, we investigated IDR-1018 using human cells found in skin-primary fibroblasts, primary keratinocytes, and the MeWo melanocytes cell line. IDR-1018 promoted cell proliferation and expression of marker of proliferation Ki-67, matrix metalloproteinase 1, and hyaluronan synthase 2 by fibroblasts. In keratinocytes, a drastic increase in expression was observed for Ki-67, matrix metalloproteinase 1, C-X-C motif chemokine receptor type 4, C-X-C motif chemokine receptor type 7, fibroblast growth factor 2, hyaluronan synthase 2, vascular endothelial growth factor, and elastin, reflecting an intense stimulation of these cells. In melanocytes, increased migration and proliferation were observed following IDR-1018 treatment. The capacity of IDR-1018 to promote dermal contraction was verified using a dermal model. Finally, using a 3D human skin equivalent lesion model, we revealed that the regenerative potential of IDR1018, previously tested in mice and pigs, is valid for human skin tissue. Lesions closed faster in IDR-1018-treated samples, and the gene expression signature observed in 2D was reproduced in the 3D human skin equivalents. Overall, the present data show the regenerative potential of IDR-1018 in an experimental system comprising human cells, underscoring the potential application for clinical investigation.

Correlation of Parasite Burden, kDNA Integration, Autoreactive Antibodies, and Cytokine Pattern in the Pathophysiology of Chagas Disease

Chagas disease (CD), caused by the protozoan Trypanosoma cruzi (T. cruzi), is the main parasitic disease in the Western Hemisphere. Unfortunately, its physiopathology is not completely understood, and cardiomegaly development is hard to predict. Trying to explain tissue lesion and the fact that only a percentage of the infected individuals develops clinical manifestations, a variety of mechanisms have been suggested as the provokers of CD, such as parasite persistence and autoimmune responses. However, holistic analysis of how parasite and host-related elements may connect to each other and influence clinical outcome is still scarce in the literature. Here, we investigated murine models of CD caused by three different pathogen strains: Colombian, CL Brener and Y strains, and employed parasitological and immunological tests to determine parasite load, antibody reactivity, and cytokine production during the acute and chronic phases of the disease. Also, we developed a quantitative PCR (qPCR) protocol to quantify T. cruzi kDNA minicircle integration into the mammalian host genome. Finally, we used a correlation analysis to interconnect parasite- and host-related factors over time. Higher parasite load in the heart and in the intestine was significantly associated with IgG raised against host cardiac proteins. Also, increased heart and bone marrow parasitism was associated with a more intense leukocyte infiltration. kDNA integration rates correlated to the levels of IgG antibodies reactive to host cardiac proteins and interferon production, both influencing tissue inflammation. In conclusion, our results shed light into how inflammatory process associates with parasite load, kDNA transfer to the host, autoreactive autoantibody production and cytokine profile. Altogether, our data support the proposal of an updated integrative theory regarding CD pathophysiology.

Oral feeding of Lactobacillus bulgaricus N45.10 inhibits the lung inflammation and airway remodeling in murine allergic asthma: Relevance to the Th1/Th2 cytokines and STAT6/T-bet

Asthma is a chronic disease with impacts on public health. It affects the airways causing pulmonary inflammation mediated by CD4 T cells type Th2, eosinophilia, mucus hypersecretion, and elevated IgE. The unbalance between cytokines and transcription factors is an important feature in asthma. Probiotics has gaining highlight as a therapy for chronic diseases. Thus, we investigate the Lactobacillus bulgaricus (Lb) effect in murine allergic asthma. BALB/c-mice were sensitized to ovalbumin (OA) on days 0 and 7 and were challenged from day 14-28 with OA. Mice received Lb seven days prior to sensitization and it was kept until day 28. The Lb attenuated the eosinophils infiltration, mucus and collagen secretion, IgE production, pro-inflammatory cytokines, TLR4 expression, GATA3, STAT6 and RORγt in lung. Otherwise, Lb increased the anti-inflammatory cytokines, the T-bet and foxp3. Finally, Lb attenuated the allergic asthma-induced inflammation and airway remodeling by interfering on Th1/Th2 cytokines and STAT6/T-bet transcription factors.

Breaking the frontiers of cosmetology with antimicrobial peptides

Antimicrobial peptides (AMPs) are mostly endogenous, cationic, amphipathic polypeptides, produced by many natural sources. Recently, many biological functions beyond antimicrobial activity have been attributed to AMPs, and some of these have attracted the attention of the cosmetics industry. AMPs have revealed antioxidant, self-renewal and pro-collagen effects, which are desirable in anti-aging cosmetics. Additionally, AMPs may also be customized to act on specific cellular targets. Here, we review the recent literature that highlights the many possibilities presented by AMPs, focusing on the relevance and impact that this potentially novel class of active cosmetic ingredients might have in the near future, creating new market outlooks for the cosmetic industry with these molecules as a viable alternative to conventional cosmetics.

Beneficial effect of low-level laser therapy in acute lung injury after i-I/R is dependent on the secretion of IL-10 and independent of the TLR/MyD88 signaling

The use of low-level laser for lung inflammation treatment has been evidenced in animal studies as well as clinical trials. The laser action mechanism seems to involve downregulation of neutrophil chemoattractants and transcription factors. Innate immune responses against microorganisms may be mediated by toll-like receptors (TLR). Intestinal ischemia and reperfusion (i-I/R) lead to bacterial product translocation, such as endotoxin, which consequently activates TLRs leading to intestinal and lung inflammation after gut trauma. Thus, the target of this study was to investigate the role of TLR activation in the laser (660 nm, 30 mW, 67.5 J/cm², 0.375 mW/cm², 5.4 J, 180 s, and spot size with 0.08 cm²) effect applied in contact with the skin on axillary lymph node in lung inflammation induced by i-I/R through a signaling adaptor protein known as myeloid differentiation factor 88 (MyD88). It is a quantitative, experimental, and laboratory research using the C57Bl/6 and MyD88^-/- mice (n = 6 mice for experimental group). Statistical differences were evaluated by ANOVA and the Tukey-Kramer multiple comparisons test to determine differences among groups. In order to understand how the absence of MyD88 can interfere in the laser effect on lung inflammation, MyD88^-/- mice were treated or not with laser and subjected to occlusion of the superior mesenteric artery (45 min) followed by intestinal reperfusion (4 h). In summary, the laser decreased the MPO activity and the lung vascular permeability, thickened the alveolar septa, reduced both the edema and the alveolar hemorrhage, as well as significantly decreased neutrophils infiltration in MyD88-deficient mice as well in wild-type mice. It noted a downregulation in chemokine IL-8 production as well as a cytokine IL-10 upregulation in these animals. The results also evidenced that in absence of IL-10, the laser effect is reversed. Based on these results, we suggest that the beneficial effect of laser in acute lung injury after i-I/R is dependent on the secretion of IL-10 and independent of the TLR/MyD88 signaling.

Adenosine production: a common path for mesenchymal stem-cell and regulatory T-cell-mediated immunosuppression

Adenosine is an important molecule that exerts control on the immune system, by signaling through receptors lying on the surface of immune cells. This nucleotide is produced, in part, by the action of the ectoenzymes CD39 and CD73. Interestingly, these proteins are expressed on the cell surface of regulatory T-cells (Tregs) and mesenchymal stromal cells (MSCs)-two cell populations that have emerged as potential therapeutic tools in the field of cell therapy. In fact, the production of adenosine constitutes a mechanism used by both cell types to control the immune response. Recently, great scientific progress was obtained regarding the role of adenosine in the inflammatory environment. In this context, the present review focuses on the advances related to the impact of adenosine production over the immune modulatory activity of Tregs and MSCs, and how this nucleotide controls the biological functions of these cells. Finally, we mention the main challenges and hurdles to bring such molecule to clinical settings.

Doxorubicin has in vivo toxicological effects on ex vivo cultured mesenchymal stem cells

Doxorubicin (dox) is an effective chemotherapeutic agent that leads to cardiotoxicity. An alternative treatment for dox-cardiotoxicity is autologous mesenchymal stem cells (MSCs) transplantation. It remains unclear if dox has deleterious effects on MSCs from subjects under chemotherapy, therefore this study aimed to evaluate dox in vivo toxicological effects on ex vivo cultured MSCs, inferring whether autologous transplantation may be an alternative treatment in patients who are exposed to the drug. Wistar rats received either dox or saline. Following treatments, animals were sacrificed and bone marrow MSCs were isolated, characterized for cell surface markers and assessed according to their viability, alkaline phosphatase production, and proliferation kinetics. Moreover, MSCs were primed to cardiac differentiation and troponin T and connexin 43 expressions were evaluated. Compared to control, undifferentiated MSCs from dox group kept the pattern for surface marker and had similar viability results. In contrast, they showed lower alkaline phosphatase production, proliferation rate, and connexin 43 expression. Primed MSCs from dox group showed lower troponin T levels. It was demonstrated a toxic effect of dox in host MSCs. This result renders the possibility of autologous MSCs transplantation to treat dox-cardiotoxicity, which could be a non-suitable option for subjects receiving such antineoplastic agent.

Cytoplasmic-targeted parvalbumin blocks the proliferation of multipotent mesenchymal stromal cells in prophase

Introduction

Multipotent mesenchymal stromal cells (MSCs) have gained considerable interest because of their potential use in the treatment of a variety of diseases and injuries. Although remarkable advancements have been made in clinical studies, substantial concerns still regard the safety of MSCs. Some evidence suggests that MSCs can spontaneously generate a population of cells with tumorigenic potential. Thus, studying the molecular mechanisms that control the proliferation of MSCs may be a necessary step toward the development of strategies for safe clinical practice. Ca²⁺ is a second messenger that mediates a wide range of cellular responses, including the regulation of cell proliferation, but little is known about its function in MSCs. The aim of this study was to investigate the effects of targeted Ca²⁺ buffering on MSCs proliferation in vitro.

Methods

Here, we used an adenoviral (Ad) vector encoding the Ca²⁺ chelator protein parvalbumin (PV) fused to a nuclear exclusion signal (NES) and the Discosoma red fluorescent protein (DsRed) to investigate the function of cytoplasmic Ca²⁺ signals on MSC proliferation. Confocal microscopy was used to demonstrate that PV-NES-DsRed was expressed in the cytoplasm. Ca²⁺ signaling was monitored by using Fluo-4-AM. Fluorescence-activated cell sorting (FACS) analysis of cells that were stained with propidium iodide was used as a quantitative measure of cell death. The mitotic index was assessed by immunofluorescence, and the expression of cyclins was examined with Western blot.

Results

Our results show that the Ad-PV-NES-DsRed fusion protein decreased serum-induced Ca²⁺ signaling and blocked the proliferation of rat adipose-derived MSCs (AT-MSCs) in prophase. FACS analysis revealed that Ad-PV-NES-DsRed did not induce cell death in AT-MSCs. Furthermore, Western blot analysis demonstrated that Ad-PV-NES-DsRed reduced extracellular signal-regulated kinase (Erk1/2) phosphorylation and cyclin B1 expression. Buffering cytosolic Ca²⁺ did not alter the expression of cyclins A/D1/D2/D3/E and E2.

Conclusions

Our results show that cytoplasmic Ca²⁺ signals are important for AT-MSCs progression beyond prophase because of their effects on Erk phosphorylation and cyclin B1 expression.

Neuroprotective effects of mesenchymal stem cells on spinal motoneurons following ventral root axotomy: synapse stability and axonal regeneration

Compression of spinal roots is an important medical problem, which may arise from intervertebral disc herniation, tumor growth or as a result of high energy accidents. Differently from avulsion, root crushing maintains the central/peripheral nervous system (CNS/PNS) connection, although the axons are axotomized and motoneurons degenerate. Such neuronal death may decrease and delay motor function recovery. In the present study we have investigated the neuroprotective effects of mesenchymal stem cell (MSC) therapy following such proximal lesions. Motor recovery and synaptic stabilization were analyzed by the use of morphological and functional approaches. For that, crushing the ventral roots at L4, L5 and L6 was unilaterally performed in Lewis rats. Four weeks after injury, an increased motoneuron survival was observed in the MSC-treated group, coupled with a smaller decrease of inputs at the motoneuron surface and nearby neuropil, seen by synaptophysin and synapsin immunolabeling and decreased astrogliosis, seen by GFAP immunolabeling. In this sense, MSC-treated group displayed a significant preservation of GABAergic terminals, indicating a possible neuroprotection to glutamate excitotoxicity. Motor function recovery was acutely improved in MSC-treated group as compared to Dulbeco's modified eagle medium (DMEM)-treated. Overall, we provide evidence that ventral root crushing (VRC), although milder than avulsion, results in significant loss of motoneurons (~51%) that can be reduced by MSC administration within the spinal cord. Such treatment also improves the number of synapses immunoreactive against molecules present in inhibitory inputs. Also, an increased number of regenerated axons was obtained in the MSC-treated group, in comparison to the DMEM-treated control. Overall, MSC therapy acutely improved limb strength and gait coordination, indicating a possible clinical application of such treatment following proximal lesions at the CNS/PNS interface.

Reversible sphere-to-lamellar wetting transition at the interface of a diblock copolymer system

We use ellipsometry to investigate a transition in the morphology of a sphere-forming diblock copolymer thin-film system. At an interface the diblock morphology may differ from the bulk when the interfacial tension favours wetting of the minority domain, thereby inducing a sphere-to-lamella transition. In a small, favourable window in energetics, one may observe this transition simply by adjusting the temperature. Ellipsometry is ideally suited to the study of the transition because the additional interface created by the wetting layer affects the polarisation of light reflected from the sample. Here we study thin films of poly(butadiene-ethylene oxide) (PB-PEO), which order to form PEO minority spheres in a PB matrix. As temperature is varied, the reversible transition from a partially wetting layer of PEO spheres to a full wetting layer at the substrate is investigated.

Surface nucleation in the crystallisation of polyethylene droplets

The division of semi-crystalline polymeric material into small domains is an effective tool for studying crystal nucleation. The scaling behavior of the nucleation rate as a function of domain size can reveal important information about the mechanism responsible for the birth of a crystal nucleus. We have investigated the process of crystal nucleation in a system of dewetted polyethylene droplets. Through the use of a correlation sample analysis, we are able to differentiate between heterogeneous and homogeneous nucleation mechanisms in a droplet sample. An analysis of the dependence of the nucleation rate on droplet size reveals that the nucleation probability scales with the surface area of the droplet.

Direct visualisation of homogeneous and heterogeneous crystallisation in an ensemble of confined domains of poly(ethylene oxide)

We present a study of homogeneous and heterogeneous nucleation in polymer crystallisation. In bulk samples the crystallization is typically dominated by nucleation from defects (heterogeneous nucleation), and consequently studies must rely on sample preparation to minimize this effect. We present a study of nucleation within discrete droplets of poly(ethylene oxide) that are formed by the dewetting of a thin film on an unfavourable substrate. The samples provide an ensemble of impurity-free droplets, with length scales that can easily be measured. We show that the data for heterogeneous and homogeneous nucleation is qualitatively different, and that the data mirrors the fundamental differences in the underlying mechanisms for the two nucleation processes. The experiments presented here provide a simple method that can be used to study heterogeneous and homogeneous nucleation in great detail.

[Intestinal duplications. A survey of 18 cases]

OBJECTIVE

The present study analyses the experience of two centers in the management of intestinal duplications in children.

MATERIAL AND METHODS

We retrospectively reviewed the medical records of a series of 18 children with intestinal duplication (January 1993 to December 1999). The median age was 11 months (range: 9 days to 12 years). The variables analysed were: clinical presentation, diagnosis, localization, anatomic type, treatment, and complications. The relationship between age and clinical presentation was also analysed.

RESULTS

Most cases were located in the ileum (n 14; 78 %) and presented with rectal bleeding (36 %) or intussusception (36 %). Most symptomatic cases in the first year of life presented with intussusception (n 5/6). All duplications, except one located in the ascending colon, were cystic. 99mTc-pertechnate abdominal scan was positive in three out of five patients. One case was diagnosed by prenatal ultrasonography. Diagnosis was confirmed by laparoscopy in three patients and by laparotomy in the remaining patients. In one patient, cystic esophageal duplication presented in the neonatal period as respiratory distress. Diagnosis as well as excision was performed by thoracoscopy. Of the two gastric duplications, one was diagnosed by prenatal ultrasonography and the other by laparotomy. Treatment consisted of segmental enterectomy (n 14) or excision of the lesion without enterectomy (n 4). No complications were found during a mean follow-up of 3 years.

CONCLUSIONS

The onset of intestinal duplication may be late. The lesions were most commonly located in the ileum and were cystic. Clinical presentation was related to age. Minimally invasive surgery plays an important role in the management of these lesions.

[Intestinal duplication. A diagnostic and therapeutic challenge]

Duplications of the alimentary tract are rare congenital anomalies. The symptoms often mimic other surgical diseases and the diagnostic workup presents low accuracy. The charts of twelve children with intestinal duplications were reviewed. Their ages ranged from 13 days to 12 years (median: 12 months). The majority of the cases were located at ileum (n = 9). These children presented: rectal bleeding (n = 4), intussusception (n = 3), intestinal obstruction (n = 1) and hemoperitoneum (n = 1). All that were symptomatic before 1 year of age presented with intussusception (n = 3/3). All, except one colonic case was cystic. 99mTc abdominal scan was positive in 3 cases presenting rectal bleeding. One child with gastric duplication was diagnosed prenatally. Treatment consisted of enterectomy in all but one case, with no complications. Experience in the diagnostic workup and management is important to achieve a low morbidity rate in this congenital anomaly, which may present delayed manifestations.

Neonatal perforation of a Y-shaped sigmoid duplication

Tubular colonic duplications are exceedingly rare; the "Y"-shaped forms are exceptional. In the absence of associated low vertebral or urogenital malformations (often fistulas), the tubular colonic malformations frequently stay hidden for several years until a complication develops. The authors report a case of a spontaneous perforation of a Y-shaped tubular colonic duplication during the neonatal period.

[Intestinal invagination in children. Reduction with pneumo-enema]

Pneumatic reduction of intussusception in children is an effective and safe procedure, although controversy persists concerning contraindications. The shown by this procedure when compared to barium reduction have led to its implementation in our Service.

AIM

To evaluate the usefulness of a 'handicraft method' of pneumatic reduction of intussusception with very restricted contraindications (peritonitis or shock).

MATERIAL AND METHODS

The prospective study included 50 attempts at pneumatic reduction in 48 children (age range: 1.5-24 months). After confirmation of the diagnosis by ultrasonography. Then, air insufflation of the colon was performed under manometric and fluoroscopic control. After confirmation of diagnosis by ultrasonography, air insufflation of the colon was performed under manometric and fluoroscopic control in an operative room. Evolution longer than 24 hours was considered diagnostic delay, leukocytosis if WBC > 15 x 10(9)/l and distal localisation after splenic angle. Immediate laparotomy was undertaken in case of unsuccessful or doubtful reduction.

RESULTS

Thirty-five reduction procedures (70%) were effective ab initio. In the 15 children submitted to laparotomy, seven were completely reduced (14%), five were manually reduced (10%), two presented intestinal necrosis (4%) and one (recurrence) had an ileal duplication (2%). The "real" efficacy (84%) was lower, even though significantly affected by diagnostic delay (81% vs 83%), rectal bleeding (81% vs 100%) or leukocytosis (71% vs 81%); efficacy was significantly lower only in distal localised cases (67% vs 97%, p = 0.02). There was one more recurrence (4%) and no other complications.

CONCLUSIONS

The adopted method of pneumatic reduction was highly effective with low morbidity. Restricted contraindications were appropriate.

Laparoscopic colonic mapping of dysganglionosis

Retention of a proximal aganglionic segment or the unrecognized coexistence of other dysganglionoses may jeopardize the definitive surgical treatment of Hirschsprung's disease (HD). To assess the extent of the disease and/or the presence of other dysganglionoses without an additional laparotomy, we developed a laparoscopic-assisted technique to perform colonic full-thickness biopsies. After creation of a pneumoperitoneum, a 5-mm laparoscope is inserted in the supraumbilical area and a working 10/12-mm port is placed in the left iliac fossa. The sigmoid/descending colon is grasped and pulled through the abdominal wall and a full-thickness biopsy done. The same procedure is applied to the transverse and ascending colon. Rectal and colonic biopsy specimens were studied using enzyme histochemical methods. Over the last year, five children aged 7 months to 12 years with dysganglionosis underwent laparoscopic-assisted mapping of the colon. Previous rectal suction biopsies were diagnostic of HD in three patients and suspicious of hypoganglionosis in two. Proximal full-thickness biopsies revealed: normal colon in two cases of HD; coexistent type B intestinal neuronal dysplasia up to the descending colon in the other case of HD; and hypoganglionosis up to the ascending colon in the two patients with suspected hypoganglionosis. The procedures were performed easily, the patients being discharged after 36 to 48 h with no complications. Four children have already undergone pull-through procedures with resection of the affected colon in adhesion-free abdominal cavities and did not develop constipation or enterocolitis. Laparoscopic-assisted mapping of the entire colon is a simple, safe, and effective procedure that may contribute to improving the outcome of intestinal dysganglionosis by better characterization of the disease.

[Prognostic indexes derived from ventricular morphology in congenital diaphragmatic hernia induced by nitrofen]

BACKGROUND

Some indices derived from cardiac morphology have been proposed as prognostic factors in fetuses and newborns with congenital diaphragmatic hernia (CDH). These would be of interest in evaluating the risk of pulmonary hypoplasia and the need for surgery in the fetus. The aim of this study was to evaluate the heart-related indices in the nitrofen-induced CDH rat model.

METHODS

At day 9 1/2 of gestation dated pregnant female Wistar rats received 100 mg of nitrofen. Fetuses were harvested at day 21 1/2 by laparotomy. The fetuses exposed to nitrofen without CDH were defined as the control group (n = 38) while the fetuses exposed to nitrofen with CDH were defined as the CDH group (n = 30). The hearts from both groups were weighed, processed for paraffin embedding and fragmented in serial 7 microns thick transverse sections. In the hearts without cardiac morphological defects the right and the left ventricular cavity volumes were estimated. These allowed calculation of cardioventricular and left-ventricular mass indices.

RESULTS

In the fetuses without cardiac malformations, no significant difference was found regarding heart-to-body weight ratio, cardioventricular index or left ventricular mass between the study groups.

CONCLUSION

In this model the presence of CDH was not associated with any alteration in cardiac dimension, in the absence of structural malformations. These results suggest that the indices derived from ventricular morphology should not be used to evaluate the prognosis in fetuses and newborns with CDH.

Delayed gastric emptying and gastroesophageal reflux: a pathophysiologic relationship

BACKGROUND

Delayed gastric emptying (DGE) is frequent in patients with gastroesophageal reflux (GER), but its pathophysiologic role has not yet been established. To identify a relationship between DGE and GER, we assessed whether DGE increases esophageal acid exposure and the related importance of possible mechanisms.

METHODS

Thirty pediatric patients with pathological GER were divided according to gastric emptying scintigraphy into a DGE group (n = 14) and normal-emptying group (n = 16). The esophageal pH-monitoring parameters of the two groups were compared with respect to the individual variation between postprandial and fasting periods.

RESULTS

Patients with DGE had less total acid exposure than did those with normal emptying, but patients in both groups had a pathological fraction of time when pH was below 4 in both the postprandial (median: 18 vs. 27.6; P = 0.49) and fasting (8.5 vs. 23.9; P = 0.01) periods. Patients in the normal-emptying group had similar fraction of time when pH was below 4 in the postprandial and fasting periods. However, patients in the group with DGE had a fraction of time when pH was below 4 in the postprandial period that was almost double that presented in fasting period (postprandial to fasting ratio: 2.11:0.90; P = 0.002). The postprandial to fasting ratio for episodes per hour was similar in the two groups (1.81 vs. 1.79; P = 0.62). Patients with DGE had a significantly higher frequency of long episodes in the postprandial period than did those with normal emptying (62.5% vs. 38.2%; P = 0.04). The occurrence of the longest episode in the postprandial period was also significantly higher for patients with DGE (57.1% vs. 6.2%; P = 0.003).

CONCLUSIONS

DGE seems to accentuate postprandial reflux by increasing the volume of refluxate per episode of reflux through an underlying incompetent lower esophageal sphincter.

Detection of N-myc amplification in neuroblastomas using Southern blotting on fine needle aspirates

OBJECTIVE

To verify the possibility of detecting N-myc amplification in fine needle aspiration (FNA) cytology from neuroblastomas by the Southern blotting technique.

STUDY DESIGN

Fifteen neuroblastomas diagnosed by FNA in the Department of Pathology, Hospital de S. João, between 1990 and 1998, were studied for N-myc amplification using the Southern blotting technique in cytologic and histologic material.

RESULTS

DNA extraction from the cytologic material was performed in all cases (N = 15). In two cases the quality/quantity of the DNA did not allow the study of N-myc status by the Southern blotting technique. We detected N-myc amplification in 1 of 13 patients (7.6%) from whom material was available for genetic study.

CONCLUSION

It is possible to use the Southern blotting technique to demonstrate N-myc amplification in material obtained from FNA of neuroblastomas.

Histochemical and immunohistochemical study of the intrinsic innervation in colonic dysganglionosis

Defective innervation of the neuromuscular junctions (NMJ) was recently described in intestinal neuronal dysplasia type B (IND B). The aim of the present study was to correlate the alterations in NMJs to other classically described parameters in dysganglionoses and to determine the relationship between NMJ abnormalities in IND B and clinical symptoms. The rectal biopsies and full-thickness colonic biopsy specimens of 17 patients were studied applying histochemical (acetylcholinesterase [AChE], lactic dehydrogenase [LDH], and succinic dehydrogenase [SDH] reactions) and immunohistochemical (neuronal-cell adhesion molecule [NCAM] and SY antibodies) methods. Thirteen patients had Hirschsprung's disease (HD). IND B was diagnosed in 11 (associated with HD in 8 cases, isolated in 2, and associated with hypoganglionosis in 1). In the aganglionic segment of HD there was very intense AChE activity; in contrast, NCAM- and SY-immunoreactive nerve fibers were markedly decreased. A spectrum of abnormalities was observed in IND B, usually more severe in the most distal segments: giant and immature ganglia in the submucous plexus were observed in all cases; heterotopic myenteric ganglia were frequent (72.7%); hyperganglionosis was observed in 6 (54.5%) and was not related to the patients' age; thick and tortuous NCAM- and SY-immunoreactive nerve fibers, irregularly distributed in the colonic wall, were observed in 81.8% of the cases. No relationship was observed between abnormalities of NCAM- and SY-immunoreactive nerve fibers and AChE activity, ganglion-cell maturity, heterotopy, or the clinical symptoms presented by the patients with IND B. In hypoganglionism, low AChE activity and a slight decrease in NCAM- and SY-immunoreactive nerves were observed. Thick and tortuous, irregularly-distributed intrinsic NCAM- and SY-immunoreactive nerves were observed in every colon layer in IND B. Our results do not support IND B as a NMJ disorder.

Field observations of dilution on the Ipanema Beach outfall

Field observations of the Ipanema Beach, Rio de Janeiro, ocean sewage outfall are presented. Measurements of dilution and other wastefield characteristics were obtained by adding dye tracer to the effluent and measuring in-situ. Simultaneous measurements of oceanographic conditions were made by Acoustic Doppler Current Profilers, thermistor strings, and profiling instruments. Four experiments were performed, two during unstratified conditions when the plume was surfacing, and two during conditions of strong stratification when the plume was submerged. The minimum dilution varied from 30 to 130. The measurements reflect the worst case conditions as the campaigns were all made for weak currents.

[Cobb's collar. Unusual cause of hematuria]

The Cobb's collar is a congenital narrowing of the bulbar urethra with variable clinical presentation and obstruction grade. Herein we report a clinical case of a 13-year-old boy presenting terminal macroscopic haematuria and post-mictional urethral bleeding. At cystoscopy a membrane on the bulbar urethra distal to the external sphincter and prominent vessels in the prostatic urethra were found. Transurethral endoscopic incision was carried out with no complications or recurrence at 9-month follow-up. The authors briefly review the embryopathogenesis, clinical features and treatment of this uncommon anomaly.

Heart-related indices in experimental diaphragmatic hernia

BACKGROUND

Heart-related indices have been suggested as useful tools to evaluate left ventricular (LV) hypoplasia, which might predict the outcome of fetuses and infants with congenital diaphragmatic hernia (CDH). The current study analyzed the behavior of such indices in the nitrofen-induced CDH rat model.

METHODS

Dated pregnant Wistar rats received at day 9.5 of gestation either a dose of 100 mg of nitrofen or just the vehicle. Body, lung, and heart weights were measured in 12 newborn rats not exposed to nitrofen (Ctrl group) and 68 animals exposed to nitrofen: 30 without CDH (non-CDH group) and 38 with left CDH (CDH group). Each heart was fragmented in 7-microm thick sections. Only hearts with no evidence of cardiac morphologic defects (CMD) were studied further to estimate right and left ventricular cavity volumes, septal, right, and left ventricular free wall masses. These parameters allowed the calculation of the cardio-ventricular (CVindex) and LV mass indices. The aorta-to-pulmonary artery ratio also was calculated.

RESULTS

Excluding fetuses with CMD, the heart-to-body weight ratio was reduced significantly in animals exposed to nitrofen, whereas no significant differences were observed between non-CDH versus CDH groups. Although the left and right ventricular cavity volumes were both reduced significantly in nitrofen-treated rats, they were not changed significantly by the existence of CDH, and the calculated CVindex was similar in the 3 groups. Estimated septal and LV masses were reduced markedly in the nitrofen-treated animals and further reduced by the presence of CDH. However, when LV mass was normalized (LV mass index) the difference became restricted to the animals exposed to nitrofen but was not influenced by the presence of CDH. Finally, the aorta-to-pulmonary artery ratio was similar in all studied groups.

CONCLUSIONS

The results of the current study suggest that, although nitrofen had been responsible by global heart hypoplasia, the presence of CDH was not associated with significant underdevelopment of the heart or of the LV in rat fetuses without CMD. Based on these results, we think that the evidence for prenatal counseling based on heart-related indices should be critically reconsidered.