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1.
Acta Paediatr ; 112(5): 1074-1081, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36843242

RESUMO

AIM: We evaluated the impact of inpatient and outpatient treatment provided by an infant nutrition foundation in Las Heras, Mendoza, Argentina and identified the factors that influenced nutritional recovery. METHODS: This 2010-2018 retrospective study was based on 300 children up to 5 years of age with primary malnutrition, who were treated by an inpatient recovery centre, then an outpatient prevention centre. We analysed the children's height, weight, psychomotor development and living conditions when they were admitted, discharged and had received 1 year of outpatient treatment. There were full data on 241 children and just admission and discharge data for 59. RESULTS: The children's mean age on admission and weight were 14.8 ± 12.4 months and 6.9 ± 2.3 kg and they stayed in hospital for a mean of 59.5 ± 49.7 days. We observed a significant increase in the weight-for-age, height-for-age and weight-for-height z-scores when all three time points were compared (p < 0.001). Psychomotor development improved considerably in all patients after treatment. The factors that negatively influenced nutritional recovery were higher age at admission, suboptimal breastfeeding practices, low birth weight, longer hospital stays, younger maternal age and overcrowded housing. CONCLUSION: Combining inpatient recovery and outpatient preventive treatment was effective for undernourished children in Argentina.


Assuntos
Transtornos da Nutrição Infantil , Desnutrição , Criança , Feminino , Humanos , Lactente , Argentina , Pacientes Internados , Desnutrição/prevenção & controle , Estado Nutricional , Pacientes Ambulatoriais , Estudos Retrospectivos , Serviços de Saúde Comunitária
2.
Nutrition ; 108: 111957, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36696705

RESUMO

OBJECTIVES: Prostate cancer (PCa) is the most common adenocarcinoma in men >50 y of age. It has a long latency period, which provides time for preventive strategies like incorporating healthy eating habits. Yerba mate (YM) intake has been associated with numerous health benefits. Since YM is one of the most popular infusions in Argentina, the of this study was to examine the influence of YM on PCa development. METHODS: We carried out an in vivo model of PCa through subcutaneous inoculation of transgenic adenocarcinoma of the mouse prostate-C1 cells in C57BL/6 mice. Subsequently, the animals were divided into two groups: mate (25 mg/mL of YM in drinking water, n = 15), and control (only drinking water, n = 15). We also developed an in vitro model to study the direct effects of YM on three human PCa cell lines: lymph node carcinoma of the prostate (LNCaP), PC-3, and DU-145. RESULTS: Our in vivo model showed that YM intake slightly reduced body weight, increased the latency of tumor appearance (P <0.01), and diminished the tumor volume (P <0.05) compared with the control group. In agreement, the expression of proliferating cell nuclear antigen, and nuclear estrogen receptor α were lower in the tumors of the mate animals (P <0.05). In vitro, YM decreased the viability, proliferation, and adhesion of the three tumor cell lines (P < 0.001) and retarded the migration of LNCaP (P <0.05) and DU-145 (P <0.005), without modifying the migration of PC-3 cells. CONCLUSIONS: YM showed anticancer effects in vitro and in vivo and were more effective on the androgen-sensitive cell line (LNCaP).


Assuntos
Adenocarcinoma , Água Potável , Ilex paraguariensis , Neoplasias da Próstata , Masculino , Camundongos , Animais , Humanos , Camundongos Endogâmicos C57BL
3.
J Dev Orig Health Dis ; 14(1): 122-131, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-35670520

RESUMO

The functional differentiation of the mammary gland (MG) is fundamental for the prevention of mammary pathologies. This process occurs throughout pregnancy and lactation, making these stages key events for the study of pathologies associated with development and differentiation. Many studies have investigated the link between mammary pathologies and thyroid diseases, but most have ignored the role of thyroid hormone (TH) in the functional differentiation of the MG. In this work, we show the long-term impact of hypothyroidism in an animal model whose lactogenic differentiation occurred at low TH levels. We evaluated the ability of the MG to respond to hormonal control and regulate cell cycle progression. We found that a deficit in TH throughout pregnancy and lactation induces a long-term decrease in Rb phosphorylation, increases p53, p21, Cyclin D1 and Ki67 expression, reduces progesterone receptor expression, and induces nonmalignant lesions in mammary tissue. This paper shows the importance of TH level control during mammary differentiation and its long-term impact on mammary function.


Assuntos
Hipotireoidismo , Glândulas Mamárias Animais , Gravidez , Feminino , Animais , Lactação/metabolismo , Hipotireoidismo/complicações , Diferenciação Celular
4.
Sci Rep ; 12(1): 8687, 2022 05 23.
Artigo em Inglês | MEDLINE | ID: mdl-35606546

RESUMO

Tumor cells can interact with neighboring adipose cells and adipocyte dedifferentiation appears to be an important aspect of tumorigenesis. We evaluated the size of adipocytes in human adipose explants from normal (hRAN) and kidney cancer (hRAT); changes in the expression of WAT and BAT/beige markers in hRAN and hRAT; the expression of epithelial-mesenchymal transition (EMT) cell markers in human kidney tumor (786-O, ACHN and Caki-1); and non-tumor (HK-2) epithelial cell lines incubated with the conditioned media (CMs) of hRAN and hRAT. We observed that hRAT adipocytes showed a significantly minor size compared to hRAN adipocytes. Also, we observed that both Prdm16 and Tbx1 mRNA and the expression of UCP1, TBX1, PPARγ, PCG1α, c/EBPα LAP and c/EBPα LIP was significantly higher in hRAT than hRAN. Finally, we found an increase in vimentin and N-cadherin expression in HK-2 cells incubated for 24 h with hRAT-CMs compared to hRAN- and control-CMs. Furthermore, desmin and N-cadherin expression also increased significantly in 786-O when these cells were incubated with hRAT-CMs compared to the value observed with hRAN- and control-CMs. We observed a significant decrease in E-cadherin expression in the ACHN cell line incubated with hRAT-CMs versus hRAN- and control-CMs. However, we did not observe changes in E-cadherin expression in HK-2, 786-O or Caki-1. The results obtained, together with the results previously published by our group, allow us to conclude that perirenal white adipose tissue browning contributes to tumor development in kidney cancer. In addition, hRAT-CMs increases the expression of mesenchymal markers in renal epithelial cells, which could indicate a regulation of EMT due to this adipose tissue.


Assuntos
Transição Epitelial-Mesenquimal , Neoplasias Renais , Tecido Adiposo/metabolismo , Tecido Adiposo Marrom/metabolismo , Tecido Adiposo Branco/metabolismo , Caderinas/metabolismo , Humanos , Neoplasias Renais/genética , Neoplasias Renais/metabolismo
5.
J Dev Orig Health Dis ; 12(4): 578-586, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-33023719

RESUMO

Maternal milk consumption can cause changes in the mammary epithelium of the offspring that result in the expression of molecules involved in the induction of differentiation, reducing the risk of developing mammary cancer later in life. We previously showed that animals that maintained a higher intake of maternal milk had a lower incidence of mammary cancer. In the present study, we evaluated one of the possible mechanisms by which the consumption of maternal milk could modify the susceptibility to mammary carcinogenesis. We used Sprague Dawley rats reared in litters of 3 (L3), 8 (L8), or 12 (L12) pups per mother in order to generate a differential consumption of milk. Whole mounts of mammary glands were performed to analyze the changes in morphology. Using real-time polymerase chain reaction (PCR), we analyzed the expression of mammary Pinc, Tbx3, Stat6, and Gata3 genes. We use the real-time methylation-specific polymerase chain reaction method to assess the methylation status of Stat6 and Gata3 CpG sites. Our findings show an increase in the size of the epithelial tree and a smaller number of ducts called terminal end buds in L3 vs. L12. We observed an increased expression of mRNA of Stat6, Gata3, Tbx3, and a lower expression of Pinc in L3 with respect to L12. Stat6 and Gata3 are more methylated in the CpG islands of the promoter analyzed in L12 vs. L3. In conclusion, the increased consumption of maternal milk during the postnatal stage generates epigenetic and morphological changes associated with the differentiation of the mammary gland.


Assuntos
Epigênese Genética , Comportamento Alimentar/fisiologia , Glândulas Mamárias Animais/crescimento & desenvolvimento , Animais , Animais Recém-Nascidos , Feminino , Tamanho da Ninhada de Vivíparos , Ratos Sprague-Dawley
6.
Oncotarget ; 10(52): 5454-5467, 2019 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-31534630

RESUMO

Tumor cells can interact with neighboring adipose tissue. We evaluated components present in human adipose explants from normal (hRAN) and kidney cancer (hRAT) tissue, and we evaluated the effects of conditioned media (CMs) from hRAN and hRAT on proliferation, adhesion and migration of tumor and non-tumor human renal epithelial cell lines. In addition, we evaluated the expression of AdipoR1, ObR, CD44, vimentin, pERK and pPI3K on cell lines incubated with CMs. hRAN were obtained from healthy operated donors, and hRAT from patients who underwent a nephrectomy. hRAT showed increased levels of versican, leptin and ObR; and decreased levels of perilipin, adiponectin and AdipoR1, compared to hRAN. Cell lines showed a significant decrease in cell adhesion and increase in cell migration after incubation with hRAT-CMs vs. hRAN- or control-CMs. Surprisingly, HK-2, 786-O and ACHN cells showed a significant decrease in cell migration after incubation with hRAN-CMs vs. control-CMs. No difference in proliferation of cell lines was found after 24 or 48 h of treatment with CMs. AdipoR1 in ACHN and Caki-1 cells decreased significantly after incubation with hRAT-CMs vs. hRAN-CMs and control-CMs. ObR and CD44 increased in tumor line cells, and vimentin increased in non-tumor cells, after incubation with hRAT-CMs vs. hRAN-CMs and control-CMs. We observed an increase in the expression of pERK and pPI3K in HK-2, 786-O and ACHN, incubated with hRAT-CMs. In conclusion, results showed that adipose microenvironment can regulate the behavior of tumor and non tumor human renal epithelial cells.

7.
Endocr Connect ; 8(3): 217-229, 2019 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-30738018

RESUMO

Epidemiological studies describe estrogens as protectors in the development of colon cancer in postmenopausal women treated with hormone replacement therapy. However, the role of progesterone in colon cancer has been minimally studied and the results are controversial. For the above, the objective of this work was to determine the hormonal regulation exerted by natural ovarian steroids on proliferation and apoptosis in an experimental model of colon cancer in ovariectomized rats treated with 17-beta estradiol and progesterone. Sprague-Dawley rats were exposed to the carcinogen 1,2-dimethylhydrazine to induce colon tumors. Thirty days later, the rats were ovariectomized and treated with estradiol (60 µg/kg), progesterone (10 mg/kg), estradiol plus progesterone (60 µg/kg and 10 mg/kg) or vehicle. We observed no significant differences in colon cancer incidence and tumor multiplicity between the groups. Nevertheless, we observed a decrease in PCNA expression and a greater number of apoptotic index, higher expression of caspase 3, cleaved PARP and cleaved caspase 8 in tumors, confirming the activation of the extrinsic pathway of apoptosis by the combined treatment. In addition, we observed a higher expression of estrogen receptor beta in these tumors. We conclude that the action of both hormones, estradiol and progesterone, is necessary to reduce proliferation and increase apoptosis in colon tumors, probably through estrogen receptor beta activation.

8.
Oncotarget ; 9(57): 31007-31017, 2018 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-30123423

RESUMO

Tumor progression depends on the tumor-stroma interaction. In the breast, adipose tissue is the predominant stromal type. We have previously demonstrated that conditioned media (CMs) from explants of human adipose tissue of tumor breasts (hATT) increase proliferation and migration of breast cancer epithelial cells when compared to human adipose tissue from normal breasts (hATN). In this work, we aim to identify specific proteins and molecular/biological pathways associated with the secretion profile of hATT and hATN explants. hATT-CMs and hATN-CMs were separated by SDS-PAGE and analyzed by means of two-dimensional nano-liquid chromatography-mass spectrometry. The data was analyzed using ProteoIQ and FunRich software. In addition, 42 cytokines from hATT-CMs and hATN-CMs were assayed by a protein antibody assay. Compared to hATN-CMs, hATT-CMs showed greater protein diversity. We found that hATT-CMs presented a greater amount of proteins related to complement system activity, metabolism and immune system, as well as proteins involved in a variety of biological processes such as signal transduction and cell communication. Specifically, apolipoprotein AI and AII, complement component 3, and vimentin and desmin were significantly increased in hATT-CMs versus hATN-CMs. Moreover, a multivariate discriminant analysis of the cytokines detected by the array showed that IL-6, MCP-2 and GRO cytokines were sufficient and necessary to differentiate hATT-CMs from hATN-CMs. This analysis also showed that the levels of these three cytokines, taken together, correlated with stage and histological grade of the tumor in the hATT-CMs group, and with body mass index in the hATN-CMs group.

9.
Oncotarget ; 8(55): 94223-94234, 2017 11 07.
Artigo em Inglês | MEDLINE | ID: mdl-29212223

RESUMO

We evaluated the effects of conditioned media (CMs) of human adipose tissue from renal cell carcinoma located near the tumor (hRATnT) or farther away from the tumor (hRATfT), on proliferation, adhesion and migration of tumor (786-O and ACHN) and non-tumor (HK-2) human renal epithelial cell lines. Human adipose tissues were obtained from patients with renal cell carcinoma (RCC) and CMs from hRATnT and hRATfT incubation. Proliferation, adhesion and migration were quantified in 786-O, ACHN and HK-2 cell lines incubated with hRATnT-, hRATfT- or control-CMs. We evaluated versican, adiponectin and leptin expression in CMs from hRATnT and hRATfT. We evaluated AdipoR1/2, ObR, pERK, pAkt y pPI3K expression on cell lines incubated with CMs. No differences in proliferation of cell lines was found after 24 h of treatment with CMs. All cell lines showed a significant decrease in cell adhesion and increase in cell migration after incubation with hRATnT-CMs vs. hRATfT- or control-CMs. hRATnT-CMs showed increased levels of versican and leptin, compared to hRATfT-CMs. AdipoR2 in 786-O and ACHN cells decreased significantly after incubation with hRATfT- and hRATnT-CMs vs. control-CMs. We observed a decrease in the expression of pAkt in HK-2, 786-O and ACHN incubated with hRATnT-CMs. This result could partially explain the observed changes in migration and cell adhesion. We conclude that hRATnT released factors, such as leptin and versican, could enhance the invasive potential of renal epithelial cell lines and could modulate the progression of the disease.

10.
J Exp Clin Cancer Res ; 36(1): 26, 2017 02 07.
Artigo em Inglês | MEDLINE | ID: mdl-28173833

RESUMO

BACKGROUND: Adipose microenvironment is involved in signaling pathways that influence breast cancer. We aim to characterize factors that are modified: 1) in tumor and non tumor human breast epithelial cell lines when incubated with conditioned media (CMs) from human breast cancer adipose tissue explants (hATT) or normal breast adipose tissue explants (hATN); 2) in hATN-CMs vs hATT-CMs; 3) in the tumor associated adipocytes vs. non tumor associated adipocytes. METHODS: We used hATN or hATT- CMs on tumor and non-tumor breast cancer cell lines. We evaluated changes in versican, CD44, ADAMTS1 and Adipo R1 expression on cell lines or in the different CMs. In addition we evaluated changes in the morphology and expression of these factors in slices of the different adipose tissues. The statistical significance between different experimental conditions was evaluated by one-way ANOVA. Tukey's post-hoc tests were performed within each individual treatment. RESULTS: hATT-CMs increase versican, CD44, ADAMTS1 and Adipo R1 expression in breast cancer epithelial cells. Furthermore, hATT-CMs present higher levels of versican expression compared to hATN-CMs. In addition, we observed a loss of effect in cellular migration when we pre-incubated hATT-CMs with chondroitinase ABC, which cleaves GAGs chains bound to the versican core protein, thus losing the ability to bind to CD44. Adipocytes associated with the invasive front are reduced in size compared to adipocytes that are farther away. Also, hATT adipocytes express significantly higher amounts of versican, CD44 and Adipo R1, and significantly lower amounts of adiponectin and perilipin, unlike hATN adipocytes. CONCLUSIONS: We conclude that hATT secrete a different set of proteins compared to hATN. Furthermore, versican, a proteoglycan that is overexpressed in hATT-CMs compared to hATN-CMs, might be involved in the tumorogenic behavior observed in both cell lines employed. In addition, we may conclude that adipocytes from the tumor microenvironment show a less differentiated state than adipocytes from normal microenvironment. This would indicate a loss of normal functions in mature adipocytes (such as energy storage), in support of others that might favor tumor growth.


Assuntos
Biomarcadores Tumorais/metabolismo , Neoplasias da Mama/metabolismo , Mama/metabolismo , Meios de Cultivo Condicionados/farmacologia , Células Epiteliais/efeitos dos fármacos , Proteína ADAMTS1/metabolismo , Tecido Adiposo/metabolismo , Tecido Adiposo/patologia , Mama/citologia , Mama/patologia , Neoplasias da Mama/patologia , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Microambiente Celular , Progressão da Doença , Células Epiteliais/citologia , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Receptores de Hialuronatos/metabolismo , Células MCF-7 , Receptores de Adiponectina/metabolismo , Versicanas/metabolismo
11.
Biomed Res Int ; 2014: 210424, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25136563

RESUMO

Prolactin (PRL) is a key player in the development of mammary cancer. We studied the effects of parity or hyperprolactinemia on mammary carcinogenesis in OFA hr/hr treated with 7,12-dimethylbenzanthracene. They were divided into three groups: nulliparous (Null), primiparous (PL, after pregnancy and lactation), and hyperprolactinemic rats (I, implanted in the arcuate nucleus with 17ß-estradiol). The tumor incidence was similar in the three groups. However, a higher percentage of regressing tumors was evident in the PL group. Serum PRL, mammary development, and mammary ß-casein content were higher in I rats compared to Null. The expression of hormone receptors was similar in the different groups. However, mammary tissue from PL rats bearing tumors had increased expression of PRL and estrogen alpha receptors compared to rats free of tumors. Our results suggest that serum PRL levels do not have relevance on the incidence of tumors, probably because the low levels of PRL in OFA rats are not further decreased by PL like in other strains. However, supraphysiological levels of PRL affect carcinogenesis. PL induces regression of the tumors due to the differentiation produced on the mammary cells. Alterations in the expression of hormonal receptors may be involved in progression and regression of tumors.


Assuntos
9,10-Dimetil-1,2-benzantraceno/toxicidade , Carcinógenos/toxicidade , Glândulas Mamárias Animais , Neoplasias Mamárias Experimentais , Proteínas de Neoplasias/sangue , Paridade , Prolactina/sangue , Animais , Feminino , Glândulas Mamárias Animais/metabolismo , Glândulas Mamárias Animais/patologia , Neoplasias Mamárias Experimentais/sangue , Neoplasias Mamárias Experimentais/induzido quimicamente , Neoplasias Mamárias Experimentais/patologia , Gravidez , Ratos
12.
Clin Transl Oncol ; 15(2): 124-31, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22855180

RESUMO

INTRODUCTION: Stromal-epithelial interactions mediate both breast development and breast cancer progression. In the present work, we evaluated the effects of conditioned media (CMs) of human adipose tissue explants from normal (hATN) and tumor (hATT) breast on proliferation, adhesion, migration and metalloproteases activity on tumor (MCF-7 and IBH-7) and non-tumor (MCF-10A) human breast epithelial cell lines. MATERIALS AND METHODS: Human adipose tissues were obtained from patients and the conditioned medium from hATN and hATT collected after 24 h of incubation. MCF-10A, MCF-7 and IBH-7 cells were grown and incubated with CMs and proliferation and adhesion, as well as migration ability and metalloprotease activity, of epithelial cells after exposing cell cultures to hATN- or hATT-CMs were quantified. The statistical significance between different experimental conditions was evaluated by one-way ANOVA. Tukey's post hoc tests were performed. RESULTS: Tumor and non-tumor breast epithelial cells significantly increased their proliferation activity after 24 h of treatment with hATT-CMs compared to control-CMs. Furthermore, cellular adhesion of these two tumor cell lines was significantly lower with hATT-CMs than with hATN-CMs. Therefore, hATT-CMs seem to induce significantly lower expression or less activity of the components involved in cellular adhesion than hATN-CMs. In addition, hATT-CMs induced pro-MMP-9 and MMP-9 activity and increased the migration of MCF-7 and IBH-7 cells compared to hATN-CMs. CONCLUSIONS: We conclude that the microenvironment of the tumor interacts in a dynamic way with the mutated epithelium. This evidence leads to the possibility to modify the tumor behavior/phenotype through the regulation or modification of its microenvironment. We developed a model in which we obtained CMs from adipose tissue explants completely, either from normal or tumor breast. In this way, we studied the contribution of soluble factors independently of the possible effects of direct cell contact.


Assuntos
Tecido Adiposo/metabolismo , Neoplasias da Mama/metabolismo , Meios de Cultivo Condicionados/metabolismo , Células Epiteliais/metabolismo , Microambiente Tumoral/fisiologia , Tecido Adiposo/patologia , Neoplasias da Mama/patologia , Adesão Celular/efeitos dos fármacos , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Meios de Cultivo Condicionados/farmacologia , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/patologia , Feminino , Humanos , Glândulas Mamárias Humanas/efeitos dos fármacos , Glândulas Mamárias Humanas/metabolismo , Glândulas Mamárias Humanas/patologia
13.
PLoS One ; 6(11): e25798, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-22087217

RESUMO

Toads (Rhinella arenarum) received training with a novel incentive procedure involving access to solutions of different NaCl concentrations. In Experiment 1, instrumental behavior and weight variation data confirmed that such solutions yield incentive values ranging from appetitive (deionized water, DW, leading to weight gain), to neutral (300 mM slightly hypertonic solution, leading to no net weight gain or loss), and aversive (800 mM highly hypertonic solution leading to weight loss). In Experiment 2, a downshift from DW to a 300 mM solution or an upshift from a 300 mM solution to DW led to a gradual adjustment in instrumental behavior. In Experiment 3, extinction was similar after acquisition with access to only DW or with a random mixture of DW and 300 mM. In Experiment 4, a downshift from DW to 225, 212, or 200 mM solutions led again to gradual adjustments. These findings add to a growing body of comparative evidence suggesting that amphibians adjust to incentive shifts on the basis of habit formation and reorganization.


Assuntos
Anfíbios/fisiologia , Hábitos , Aprendizagem , Motivação , Animais , Anuros/fisiologia , Comportamento Animal , Peso Corporal , Cloreto de Sódio
14.
Pediatr Nephrol ; 23(11): 1981-90, 2008 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-18607643

RESUMO

Postdiarrhea hemolytic uremic syndrome (HUS) is the most common cause of acute renal failure in children in Argentina. It is well established that Shiga toxin type 2 (Stx2) causes direct damage to glomerular endothelial cells and tubular epithelial cells, leading to a reduction in the water handling capacity of the kidney. In this study, we demonstrate that Stx2 and its B subunit (Stx2B) were able to inhibit water absorption across human renal tubular epithelial cell (HRTEC) monolayers without altering the short circuit current and the (3)H-mannitol permeability. Quantitative evaluation of (14)C-inulin transport across HRTEC monolayers showed a similar transport rate both before and after HRTEC treatment with Stx2 that confirmed the integrity of the paracellular pathway. Furthermore, Stx2 produced significant protein synthesis inhibition of HRTEC at concentrations as low as 0.001 ng/ml and 1 h of incubation, whereas Stx2B did not modify it at concentrations as high as 10,000 ng/ml and 6 h of incubation. Our findings suggest that whereas the action of Stx2 appears to be caused mainly by the inhibition of protein synthesis mediated by the A subunit, the binding of Stx2B subunit to the Gb3 receptor may affect the membrane mechanisms related to water absorption. We speculate that inhibition of water absorption may occur in proximal tubular cells in vivo in response to Stx2 and may contribute to the early event of HUS pathogenesis.


Assuntos
Injúria Renal Aguda/metabolismo , Células Epiteliais/metabolismo , Síndrome Hemolítico-Urêmica/metabolismo , Túbulos Renais Proximais/metabolismo , Toxina Shiga II/farmacologia , Água/metabolismo , Injúria Renal Aguda/patologia , Adulto , Apoptose/efeitos dos fármacos , Apoptose/fisiologia , Radioisótopos de Carbono , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/fisiologia , Células Cultivadas , Cultura em Câmaras de Difusão , Diuréticos Osmóticos/farmacologia , Condutividade Elétrica , Células Epiteliais/citologia , Células Epiteliais/efeitos dos fármacos , Síndrome Hemolítico-Urêmica/patologia , Humanos , Inulina/farmacocinética , Túbulos Renais Proximais/citologia , Túbulos Renais Proximais/efeitos dos fármacos , Manitol/farmacologia , Trítio
15.
Medicina (B.Aires) ; 66(supl.2): 11-15, 2006.
Artigo em Espanhol | LILACS | ID: lil-480132

RESUMO

In the last years, infection associated with Shiga toxin-producing Escherichia coli (STEC) and subsequent Hemolitic-Uremic Syndrome (HUS) became relevant as a public health since it was considered as one of the most important emergent patogen present in the food contaminated by cattle feces. STEC infection may be asymptomatic or begins with a watery diarrhea that may or may not progress to bloody diarrhea (hemorrhagic colitis) and HUS. In Argentina, HUS is the most common pediatric cause of acute renal insufficiency and the second cause of chronic renal failure. Up to now, STEC infection lacks of known effective treatment strategies that diminish risk of progression to HUS. The mechanisms by which Shiga toxin (Stx) induce HUS may help to find strategies to prevent or ameliorate HUS. In this article, recent progress that has contributed to understanding the disease pathogenesis of STEC is reviewed. New strategies to prevent further uptake of Shiga from the gut, either during the diarrheal phase or once HUS has developed are discussed.


Assuntos
Humanos , Infecções por Escherichia coli/microbiologia , Toxinas Shiga/metabolismo , Sistema Nervoso Central/metabolismo , Sistema Nervoso Central/microbiologia , Infecções por Escherichia coli/metabolismo , Infecções por Escherichia coli/fisiopatologia , Vacinas contra Escherichia coli/administração & dosagem , Escherichia coli/metabolismo , Escherichia coli/patogenicidade , Intestinos/metabolismo , Intestinos/microbiologia , Rim/metabolismo , Rim/microbiologia , Toxinas Shiga/antagonistas & inibidores
16.
Medicina (B.Aires) ; 66(supl.2): 11-15, 2006.
Artigo em Espanhol | BINACIS | ID: bin-123542

RESUMO

In the last years, infection associated with Shiga toxin-producing Escherichia coli (STEC) and subsequent Hemolitic-Uremic Syndrome (HUS) became relevant as a public health since it was considered as one of the most important emergent patogen present in the food contaminated by cattle feces. STEC infection may be asymptomatic or begins with a watery diarrhea that may or may not progress to bloody diarrhea (hemorrhagic colitis) and HUS. In Argentina, HUS is the most common pediatric cause of acute renal insufficiency and the second cause of chronic renal failure. Up to now, STEC infection lacks of known effective treatment strategies that diminish risk of progression to HUS. The mechanisms by which Shiga toxin (Stx) induce HUS may help to find strategies to prevent or ameliorate HUS. In this article, recent progress that has contributed to understanding the disease pathogenesis of STEC is reviewed. New strategies to prevent further uptake of Shiga from the gut, either during the diarrheal phase or once HUS has developed are discussed.(AU)


Assuntos
Humanos , Infecções por Escherichia coli/microbiologia , Toxinas Shiga/metabolismo , Sistema Nervoso Central/metabolismo , Sistema Nervoso Central/microbiologia , Vacinas contra Escherichia coli/administração & dosagem , Escherichia coli/metabolismo , Infecções por Escherichia coli/metabolismo , Infecções por Escherichia coli/fisiopatologia , Intestinos/metabolismo , Intestinos/microbiologia , Rim/metabolismo , Rim/microbiologia , Toxinas Shiga/antagonistas & inibidores , Escherichia coli/patogenicidade
17.
Infect Immun ; 71(7): 3971-8, 2003 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-12819084

RESUMO

Shiga toxin type 2 (Stx2) produced by Escherichia coli O:157H7 can cause hemolytic-uremic syndrome in children, a disease for which there is neither a vaccine nor an effective treatment. This toxin consists of an enzymatically active A subunit and a pentameric B subunit responsible for the toxin binding to host cells, and also found to be immunogenic in rabbits. In this study we developed eukaryotic plasmids expressing the B subunit gene of Stx2 (pStx2B) and the B subunit plus the gene coding for the A subunit with an active-site deletion (pStx2 Delta A). Transfection of eukaryotic cells with these plasmids produced proteins of the expected molecular weight which reacted with specific monoclonal antibodies. Newborn and adult BALB/c mice immunized with two intramuscular injections of each plasmid, either alone or together with the same vector expressing the granulocyte and monocyte colony-stimulating factor (pGM-CSF), elicited a specific Th1-biased humoral response. The effect of pGM-CSF as an adjuvant plasmid was particularly notable in newborn mice and in pStx2B-vaccinated adult mice. Stx2-neutralizing activity, evaluated in vitro on VERO cell monolayers, correlated with in vivo protection. This is the first report using plasmids to induce a neutralizing humoral immune response against the Stx2.


Assuntos
Vacinas contra Escherichia coli/imunologia , Síndrome Hemolítico-Urêmica/prevenção & controle , Toxina Shiga II/imunologia , Vacinas de DNA/imunologia , Animais , Anticorpos Antibacterianos/sangue , Modelos Animais de Doenças , Imunoglobulina G/sangue , Imunoglobulina G/classificação , Camundongos , Camundongos Endogâmicos BALB C , Testes de Neutralização , Plasmídeos , Transfecção
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