REGINA MAIA DE SOUZA
Projetos de Pesquisa
Unidades Organizacionais
LIM/46 - Laboratório de Parasitologia Médica, Hospital das Clínicas, Faculdade de Medicina
9 resultados
Resultados de Busca
Agora exibindo 1 - 9 de 9
- Comparative study on liposomal amphotericin B and other therapies in the treatment of mucosal leishmaniasis: A 15-year retrospective cohort study(2019) SANTOS, Carolina Rocio; TUON, Felipe Francisco; CIESLINSKI, Juliette; SOUZA, Regina Maia de; IMAMURA, Rui; AMATO, Valdir SabbagaBackground Liposomal amphotericin B (L-AMB) has been used for mucosal leishmaniasis (ML), but comparative studies on L-AMB and other drugs used for the treatment of ML have not been conducted. The present study aimed to evaluate the outcome of patients with ML who were treated with L-AMB. Methods This is a 15-year retrospective study of Brazilian patients with a confirmed diagnosis of ML. The therapeutic options for the treatment of ML consisted of L-AMB, amphotericin B lipid complex (ABLC), deoxycholate amphotericin B (d-AMB), itraconazole, antimonial pentavalent, or pentamidine. Healing, cure rate and adverse effects (AEs) associated with the drugs used to treat this condition were analyzed. Results In 71 patients, a total of 105 treatments were evaluated. The outcome of the treatment with each drug was compared, and results showed that L-AMB was superior to other therapeutic regimens (P = 0.001; odds ratio [OR] = 4.84; 95% confidence interval [CI] = 1.78-13.17). d-AMB had worse AEs than other treatment regimens (P = 0.001, OR = 0.09; 95% CI = 0.09-0.43). Approximately 66% of the patients presented with AEs during ML treatment. Although L-AMB was less nephrotoxic than d-AMB, it was associated with acute kidney injury compared with other drugs (P <0.05). Conclusion L-AMB was more effective than other therapies for the treatment of ML. However, a high incidence of toxicity was associated with its use. Therapeutic choices should be reassessed, and the development of new drugs is necessary for the treatment of ML.
- Liposomal drug delivery systems for the treatment of leishmaniasis(2022) TUON, Felipe Francisco; DANTAS, Leticia Ramos; SOUZA, Regina Maia de; RIBEIRO, Victoria Stadler Tasca; AMATO, Valdir SabbagaHuman leishmaniasis is a vector-borne, neglected infectious disease that is widely distributed in America, Africa, Europe, and Asia. Current therapy is based on old and toxic drugs, including antimonials, aminoglycosides, and amphotericin. As a neglected disease, investment in the development of new therapeutic molecules is scarce. Considering these aspects, the optimization of treatment through novel delivery systems for current therapeutic agents is an attractive alternative. The encapsulation into liposomes of drugs used in treating leishmaniasis increases the concentration of these molecules in macrophages, which may not only increase the chance of cure but also expand their therapeutic spectrum to include resistant Leishmania, as well as reducing toxicity since the drug is less exposed to healthy cells. The classical example is the liposomal formulation of amphotericin B, a well-established therapeutic option that uses liposomes to decrease the progression of renal failure in patients. However, loading other leishmanicidal drugs into liposomes, such as pentavalent antimonials, presents an opportunity for innovative and cheaper therapeutic options for the treatment of human leishmaniasis. This review aims to discuss liposomes as a drug delivery system for leishmanicidal drugs.
- Identification of Leishmania species by next generation sequencing of hsp70 gene(2022) SOUZA, Regina Maia de; MARTINS, Roberta Cristina Ruedas; FRANCO, Lucas Augusto Moyses; TUON, Felipe Francisco; OLIVEIRA JUNIOR, Isael Gomes de; SILVA, Camila Alves Maia da; IMAMURA, Rui; AMATO, Valdir SabbagaLeishmaniasis is a major public health problem worldwide. Although next generation sequencing technology has been widely used in the diagnosis of infectious diseases, it has been scarcely applied in identification of Leishmania species. The aim of this study was to compare the efficiency of MinIONTM nanopore sequencing and polymerase chain reaction restriction fragment length polymorphism in identifying Leishmania species. Our results showed that the MinIONTM sequencer was able to discriminate reference strains and clinical samples with high sensitivity in a cost and time effective manner without the prior need for culture.
- USEFULNESS OF kDNA PCR IN THE DIAGNOSIS OF VISCERAL LEISHMANIASIS REACTIVATION IN CO-INFECTED PATIENTS(2013) NICODEMO, Antonio Carlos; AMATO, Valdir Sabbaga; TUON, Felipe Francisco; SOUZA, Regina Maia de; OKAY, Thelma Suely; ALMEIDA, Lucia MariaIt is important to develop new methods for diagnosing relapses in the co-infection of visceral leishmaniasis (VL) and HIV to enable earlier detection using less invasive methods. We report a case of a co-infected patient who had relapses after VL treatment, where the qualitative kDNA PCR showed a good performance. The kDNA PCR seems to be a useful tool for diagnosing VL and may be a good marker for predicting VL relapses after treatment of co-infected patients with clinical symptoms of the disease.
- Lipid nanoparticles for amphotericin delivery in the treatment of American tegumentary leishmaniasis(2020) SOUZA, Regina Maia de; MARANHAO, Raul Cavalcante; TAVARES, Elaine Rufo; FILIPPIN-MONTEIRO, Fabiola Branco; NICODEMO, Antonio Carlos; MORIKAWA, Aleksandra Tiemi; KANASHIRO, Edite Hatsumi Yamashiro; AMATO, Valdir SabbagaLeishmaniasis occurs in the five continents and represents a serious public health challenge, but is still a neglected disease, and the current pharmacological weaponry is far from satisfactory. Triglyceride-rich nanoparticles mimicking chylomicrons (TGNP) behave metabolically like native chylomicrons when injected into the bloodstream. Previously we have shown that TGNP as vehicle to amphothericin B (AB) for treatment of fungi infection showed reduced renal toxicity and lower animal death rates compared to conventional AB. The aim of the current study was to test the tolerability and effectiveness of the TGNP-AB preparation in a murine model of Leishmania amazonensis infection. The in vitro assays determined the cytotoxicity of TGNP-AB, AB, and TGNP in macrophages and promastigote forms and the leishmanicidal activity in infected macrophages. The in vivo toxicity tests were performed in healthy mice with increasing doses of TGPN-AB and AB. Then, animals were treated with 2.5 mg/kg/day of AB, 17.5 mg/kg/day of TGNP-AB, or TGNP three times a week for 4 weeks. TGNP-AB formulation was less cytotoxic for macrophages than AB. TGNP-AB was more effective than AB against the promastigotes forms of the parasite and more effective in reducing the number of infected macrophages and the number of amastigotes forms per cell. TGNP-AB-treated animals showed lower hepatotoxicity. In addition, TGNP-AB group showed a marked reduction in lesion size on the paws and parasitic load. The TGNP-AB preparation attained excellent leishmanicidal activity with remarkable lower drug toxicity at very high doses that, due to the toxicity-buffering properties of the nanocarrier, become fully tolerable.
- Case Report: Cutaneous Leishmaniasis in a Rheumatoid Arthritis Patient Receiving Methotrexate(2022) AMATO, Valdir Sabbaga; SOUZA, Regina Maia de; FRANCO, Lucas Augusto Moyses; MARTINS, Roberta Cristina Ruedas; SILVA, Camila Alves Maia da; EMORI, Christini Takemi; CELESTE, Beatriz Julieta; CASTANHEIRA, Gabriel Victor; TUON, Felipe FranciscoThe immunosuppressive effect of methotrexate has rarely been associated with reactivation of cutaneous leishmaniasis. Here we present a case of a cutaneous leishmaniasis patient with atypical clinical symptoms without splenomegaly but with cutaneous manifestations after treatment of rheumatoid arthritis with methotrexate and blood recovery of the parasite. Next-generation sequencing was used to identify Leishmania infantum chagasi in the patient's blood sample.
bookPart Leishmanaiose Visceral(2016) AMATO, Valdir Sabbaga; SOUZA, Regina Maia de; BRAZ, Lucia Maria Almeida; CAMARGO, Raphael Abegão de; TUON, Felipe Francisco Bondan; NICODEMO, Elisabeth Lima- Reactivation of cutaneous and mucocutaneous tegumentary leishmaniasis in rheumatoid arthritis patients: an emerging problem?(2017) SOUZA, Regina Maia de; ANDRADE JUNIOR, Heitor Franco de; DUARTE, Maria Irma Seixas; BRAZ, Lucia Maria Almeida; SCHUBACH, Armando de Oliveira; SILVA, Fatima Conceicao; AMATO, Valdir SabbagaRheumatoid arthritis (RA) is a chronic condition that is frequent in patients living in tropical areas exposed to leishmaniasis. RA therapy involves immunosuppressant drugs such as methotrexate (MTX), monoclonal antibodies (mAbs) and prednisone. We report an unusual presentation of cutaneous (CL) or mucocutaneous leishmaniasis (ML) in RA patients from an endemic area of leishmaniasis. A 51-year-old woman noted a cutaneous ulcer on her left ankle during MTX and prednisone RA therapy. Initially diagnosed as a venous stasis ulcer, the aspirate of the injury revealed the presence of Leishmania DNA. A 73-year-old woman presenting non-ulcerated, infiltrated and painful erythematous nodules inside her nostrils while receiving MTX, anti-TNF mAb, and prednisone for RA, had also the aspirate of injuries showing the presence of Leishmania DNA. Both patients healed after the therapy with liposomal amphotericin. The RA therapy has changed to low-dose prednisone, without further reactivation episodes. Both cases suggest that CL or ML can reactivate after administration of an immunosuppressant for RA treatment. Therefore, immunosuppressive treatments for RA should be carefully prescribed in patients from endemic areas or with a history of CL and ML.
- Treatment of mucosal leishmaniasis with amphotericin B lipid complex (ABLC)(2018) TUON, Felipe Francisco; SANTOS, Carolina Rocio; CIESLINSKI, Juliette; SOUZA, Regina Maia de; IMAMURA, Rui; AMATO, Valdir Sabbaga