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1.
Ultrastruct Pathol ; 47(3): 236-240, 2023 May 04.
Artigo em Inglês | MEDLINE | ID: mdl-37040538

RESUMO

Clinical and biochemical presentation of adrenal tumors may rarely conflict with their histologic features. In the present report, we describe a rare case of adrenal neoplasm clinically and biochemically labeled as pheochromocytoma which at histologic examination resulted adrenal cortical tumor. The neoplasm was examined with the electron microscope which revealed the presence of electron-dense neuroendocrine-type granules next to intracytoplasmic lipid droplets. The patient underwent laparoscopic left adrenalectomy which leads to normalization of 24 h urinary metanephrine and normetanephrine. This exceptional entity should be taken into consideration when the clinical and laboratory features conflict with the histological examination. The pathologist can clarify the mixed nature of the tumor by means of the identification of neuroendocrine granules at the electron microscope examination.


Assuntos
Neoplasias do Córtex Suprarrenal , Neoplasias das Glândulas Suprarrenais , Adenoma Adrenocortical , Feocromocitoma , Humanos , Adenoma Adrenocortical/cirurgia , Feocromocitoma/diagnóstico , Feocromocitoma/patologia , Feocromocitoma/cirurgia , Neoplasias das Glândulas Suprarrenais/diagnóstico , Neoplasias das Glândulas Suprarrenais/patologia , Neoplasias das Glândulas Suprarrenais/cirurgia , Neoplasias do Córtex Suprarrenal/diagnóstico , Neoplasias do Córtex Suprarrenal/patologia , Neoplasias do Córtex Suprarrenal/cirurgia , Normetanefrina , Adrenalectomia/métodos
2.
J Cell Mol Med ; 24(10): 5565-5577, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32301278

RESUMO

Malignant mesothelioma (MM) is an aggressive asbestos-related cancer of the serous membranes. Despite intensive treatment regimens, MM is still a fatal disease, mainly due to the intrinsic resistance to current therapies and the lack of predictive markers and new valuable molecular targets. Protein arginine methyltransferase 5 (PRMT5) inhibition has recently emerged as a potential therapy against methylthioadenosine phosphorylase (MTAP)-deficient cancers, in which the accumulation of the substrate 5'-methylthioadenosine (MTA) inhibits PRMT5 activity, thus sensitizing the cells to further PRMT5 inhibition. Considering that the MTAP gene is frequently codeleted with the adjacent cyclin-dependent kinase inhibitor 2A (CDKN2A) locus in MM, we assessed whether PRMT5 could represent a therapeutic target also for this cancer type. We evaluated PRMT5 expression, the MTAP status and MTA content in normal mesothelial and MM cell lines. We found that both administration of exogenous MTA and stable PRMT5 knock-down, by short hairpin RNAs (shRNAs), selectively reduced the growth of MTAP-deleted MM cells. We also observed that PRMT5 knock-down in MTAP-deficient MM cells reduced the expression of E2F1 target genes involved in cell cycle progression and of factors implicated in epithelial-to-mesenchymal transition. Therefore, PRMT5 targeting could represent a promising new therapeutic strategy against MTAP-deleted MMs.


Assuntos
Deleção de Genes , Regulação Neoplásica da Expressão Gênica , Inativação Gênica , Mesotelioma/genética , Proteína-Arginina N-Metiltransferases/genética , Purina-Núcleosídeo Fosforilase/genética , Linhagem Celular Tumoral , Cromatografia Líquida , Transição Epitelial-Mesenquimal/genética , Técnicas de Silenciamento de Genes , Humanos , Imuno-Histoquímica , Mesotelioma/metabolismo , Mesotelioma/patologia , Espectrometria de Massas em Tandem
3.
Mediators Inflamm ; 2017: 9524594, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29097850

RESUMO

Little is known about the cause and pathophysiology of middermal elastolysis (MDE). In this condition, variable inflammatory infiltrate may be present or not together with loss of elastic fibres in the middermis that spares both papillary and lower reticular dermis. MDE may be a consequence of abnormal extracellular matrix degradation related to an imbalance between elastolytic enzymes released from inflammatory and resident cells and their naturally occurring inhibitors. However, the cause of this imbalance is still an object of investigation. In order to shed light on the role of fibroblasts in MDE, we used fibroblast cultures from MDE and control subjects to evaluate matrix metalloproteinases (MMPs) and their major inhibitor TIMP-1, which in combination with neutrophil or macrophage proteases released in inflamed areas may influence the elastolytic burden. We demonstrate that fibroblasts derived from MDE produce in vitro low levels of TIMP-1, the major inhibitor of MMPs. Elevated levels of MMP-2, MMP-14, and TIMP-2 capable to activate in a cooperative manner pro-MMP-2 are present in MDE tissue samples. Additionally, significant reaction for MMP-1 is present in the same MDE areas. These data all together suggest that ECM changes in MDE are due to cooperation of different cell populations (i.e., inflammatory cells and fibroblasts).


Assuntos
Fibroblastos/metabolismo , Dermatopatias/metabolismo , Células Cultivadas , Feminino , Fibroblastos/imunologia , Humanos , Imuno-Histoquímica , Metaloproteinase 2 da Matriz/metabolismo , Metaloproteinases da Matriz/metabolismo , Microscopia , Pessoa de Meia-Idade , Pele/imunologia , Pele/metabolismo , Pele/patologia , Dermatopatias/imunologia , Inibidor Tecidual de Metaloproteinase-1/metabolismo , Inibidor Tecidual de Metaloproteinase-2/metabolismo
4.
Eur Arch Otorhinolaryngol ; 269(10): 2295-9, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22791471

RESUMO

Ciliary aplasia is a rare congenital disease that alters the normal function of the mucociliary apparatus in several organs. Patients generally present with severe recurrent and chronic infections of the airways. A high suspect of this disorder is mandatory to perform correct diagnosis and provide prompt treatment. The authors describe the history of two siblings affected by primary ciliary aplasia that was associated with hydrocephalus in one case. A careful description of diagnostic procedures and treatment of this extremely rare disorder is also presented.


Assuntos
Transtornos da Motilidade Ciliar/complicações , Hidrocefalia/complicações , Brônquios/ultraestrutura , Criança , Doença Crônica , Transtornos da Motilidade Ciliar/diagnóstico , Transtornos da Motilidade Ciliar/terapia , Feminino , Humanos , Masculino , Microscopia Eletrônica de Transmissão , Mucosa Nasal/ultraestrutura , Mucosa Respiratória/ultraestrutura
5.
Cancers (Basel) ; 14(21)2022 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-36358635

RESUMO

The primary cilium (PC) is a sensory organelle present on the cell surface, modulating the activity of many pathways. Dysfunctions in the PC lead to different pathologic conditions including cancer. Hedgehog signaling (Hh) is regulated by PC and the loss of its control has been observed in many cancers, including mesothelioma. Malignant pleural mesothelioma (MPM) is a fatal cancer of the pleural membranes with poor therapeutic options. Recently, overexpression of the Hh transcriptional activator GL1 has been demonstrated to be associated with poor overall survival (OS) in MPM. However, unlike other cancers, the response to G-protein-coupled receptor smoothened (SMO)/Hh inhibitors is poor, mainly attributable to the lack of markers for patient stratification. For all these reasons, and in particular for the role of PC in the regulation of Hh, we investigated for the first time the status of PC in MPM tissues, demonstrating intra- and inter-heterogeneity in its expression. We also correlated the presence of PC with the activation of the Hh pathway, providing uncovered evidence of a PC-independent regulation of the Hh signaling in MPM. Our study contributes to the understanding MPM heterogeneity, thus helping to identify patients who might benefit from Hh inhibitors.

6.
Chem Biol Interact ; 300: 63-72, 2019 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-30641060

RESUMO

Mammary serine protease inhibitor or Maspin has been characterized as a class II tumor suppressor gene in several cancer types, among them prostate cancer (CaP). Androgen ablation is an effective therapy for CaP, but with short-term effectiveness, thus new therapeutic strategies are actively sought. The present study is aimed to explore the effects of a glucosamine derivative, 2-(N-Carbobenzyloxy)l-phenylalanylamido-2-deoxy-ß-d-glucose (NCPA), on two CaP cell lines, PC3 and LNCaP. In particular we analyzed the impact of NCPA on Maspin production, cell viability and cell cycle progression and apoptosis/necrosis pathway activation in PC3 and LNCaP cell lines. NCPA is able to stimulate Maspin production in PC3 and not in LNCaP cell lines. NCPA blocks the PC3 cell cycle in G1 phase, by inhibiting Cyclin D1 production and induces the apoptosis, therefore interfering with aggressiveness of this androgen-insensitive cell line. Moreover, NCPA is able to induce the expression of Maspin in LNCaP cell line treated with androgen receptor inhibitor, Bicalutamide, and in turn to stimulate the apoptosis of these cells. These findings suggest that NCPA, stimulating the endogenous production of a tumor suppressor protein, could be useful in the design of new therapeutic strategies for treatment of CaP.


Assuntos
Proliferação de Células/efeitos dos fármacos , Glucosamina/análogos & derivados , Glucosamina/farmacologia , Serpinas/metabolismo , Anilidas/farmacologia , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Ciclina D1/genética , Ciclina D1/metabolismo , Glucosamina/química , Humanos , Masculino , Nitrilas/farmacologia , Neoplasias da Próstata/metabolismo , Neoplasias da Próstata/patologia , Receptores Androgênicos/química , Receptores Androgênicos/metabolismo , Serpinas/genética , Compostos de Tosil/farmacologia
7.
Blood Cancer J ; 9(12): 91, 2019 11 20.
Artigo em Inglês | MEDLINE | ID: mdl-31748534

RESUMO

MYC is the most altered oncogene in human cancer, and belongs to a large family of genes, including MYCN and MYCL. Recently, while assessing the degree of correlation between MYC gene rearrangement and MYC protein expression in aggressive B-cell lymphomas, we observed few Burkitt lymphoma (BL) cases lacking MYC protein expression despite the translocation involving the MYC gene. Therefore, in the present study we aimed to better characterize such cases. Our results identified two sub-groups of MYC protein negative BL: one lacking detectable MYC protein expression but presenting MYCN mRNA and protein expression; the second characterized by the lack of both MYC and MYCN proteins but showing MYC mRNA. Interestingly, the two sub-groups presented a different pattern of SNVs affecting MYC gene family members that may induce the switch from MYC to MYCN. Particulary, MYCN-expressing cases show MYCN SNVs at interaction interface that stabilize the protein associated with loss-of-function of MYC. This finding highlights MYCN as a reliable diagnostic marker in such cases. Nevertheless, due to the overlapping clinic, morphology and immunohistochemistry (apart for MYC versus MYCN protein expression) of both sub-groups, the described cases represent bona fide BL according to the current criteria of the World Health Organization.


Assuntos
Linfoma de Burkitt/genética , Linfoma de Burkitt/metabolismo , Regulação Neoplásica da Expressão Gênica , Genes de Troca , Genes myc , Adolescente , Adulto , Idoso , Linfoma de Burkitt/epidemiologia , Linfoma de Burkitt/patologia , Criança , Feminino , Genômica/métodos , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Imuno-Histoquímica , Imunofenotipagem , Masculino , Pessoa de Meia-Idade , Modelos Moleculares , Mutação , Conformação Proteica , RNA Mensageiro/genética , Relação Estrutura-Atividade , Translocação Genética , Adulto Jovem
8.
J Clin Endocrinol Metab ; 93(10): 3950-7, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-18664542

RESUMO

BACKGROUND: Differentiated papillary thyroid cancer is mostly sporadic, but the recurrence of the familial form has been reported. Short or dysfunctional telomeres have been associated with familial benign diseases and familial breast cancer. OBJECTIVE: The aim of our work was to study the telomere-telomerase complex in the peripheral blood of patients with familial papillary thyroid cancer (FPTC), including the measurement of relative telomere length (RTL), telomerase reverse transcriptase (hTERT) gene amplification, hTERT mRNA expression, telomerase protein activity, and search of hTERT or telomerase RNA component gene mutations. PATIENTS: Cumulating a series of patients seen at the University of Siena and a series at the University of Rome, the experiments were conducted in 47 FPTC patients, 75 sporadic papillary thyroid cancer (PTC) patients, 20 patients with nodular goiter, 19 healthy subjects, and 20 unaffected siblings of FPTC patients. RESULTS: RTL, measured by quantitative PCR, was significantly (P < 0.0001) shorter in the blood of FPTC patients, compared with sporadic PTCs, healthy subjects, nodular goiter subjects, and unaffected siblings. Also by fluorescence in situ hybridization analysis, the results confirmed shorter telomere lengths in FPTC patients (P = 0.01). hTERT gene amplification was significantly (P < 0.0001) higher in FPTC patients, compared with the other groups, and in particular, it was significantly (P = 0.03) greater in offspring with respect to parents. hTERT mRNA expression, as well as telomerase activity, was significantly higher (P = 0.0003 and P < 0.0001, respectively) in FPTC patients, compared with sporadic PTCs. RTL, measured in cancer tissues, was shorter (P < 0.0001) in FPTC patients, compared with sporadic PTCs. No mutations of the telomerase RNA component and hTERT genes were found. CONCLUSION: Our study demonstrates that patients with FPTC display an imbalance of the telomere-telomerase complex in the peripheral blood, characterized by short telomeres, hTERT gene amplification, and expression. These features may be implicated in the inherited predisposition to develop FPTC.


Assuntos
Carcinoma Papilar/sangue , Carcinoma Papilar/genética , Amplificação de Genes , Telomerase/sangue , Telomerase/genética , Telômero/fisiologia , Neoplasias da Glândula Tireoide/sangue , Neoplasias da Glândula Tireoide/genética , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma Papilar/enzimologia , Carcinoma Papilar/metabolismo , Criança , Feminino , Amplificação de Genes/fisiologia , Predisposição Genética para Doença , Humanos , Masculino , Pessoa de Meia-Idade , RNA Mensageiro/metabolismo , Telomerase/metabolismo , Telômero/química , Neoplasias da Glândula Tireoide/enzimologia , Neoplasias da Glândula Tireoide/metabolismo
9.
Respiration ; 76(2): 198-204, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18434704

RESUMO

BACKGROUND: Primary ciliary dyskinesia (PCD) is a rare recessive hereditary disorder characterized by dysmotility to immotility of ciliated and flagellated structures. Its main symptoms are respiratory, caused by defective ciliary beating in the epithelium of the upper airways (nose, bronchi and paranasal sinuses). Impairing the drainage of inhaled microorganisms and particles leads to recurrent infections and pulmonary complications. To date, 5 genes encoding 3 dynein protein arm subunits (DNAI1, DNAH5 and DNAH11), the kinase TXNDC3 and the X-linked RPGR have been found to be mutated in PCD. OBJECTIVES: We proposed to determine the impact of the DNAI1 gene on a cohort of unrelated PCD patients (n = 104) recruited without any phenotypic preselection. METHODS: We used denaturing high-performance liquid chromatography and sequencing to screen for mutations in the coding and splicing site sequences of the gene DNAI1. RESULTS: Three mutations were identified: a novel missense variant (p.Glu174Lys) was found in 1 patient and 2 previously reported variants were identified (p.Trp568Ser in 1 patient and IVS1+2_3insT in 3 patients). Overall, mutations on both alleles of gene DNAI1 were identified in only 2% of our clinically heterogeneous cohort of patients. CONCLUSION: We conclude that DNAI1 gene mutation is not a common cause of PCD, and that major or several additional disease gene(s) still remain to be identified before a sensitive molecular diagnostic test can be developed for PCD.


Assuntos
Dineínas/genética , Síndrome de Kartagener/genética , Sequência de Aminoácidos , Dineínas do Axonema , Análise Mutacional de DNA , Humanos , Dados de Sequência Molecular
10.
Ann Otol Rhinol Laryngol ; 126(4): 322-327, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28290230

RESUMO

OBJECTIVE: To investigate the prevalence of otological complications derived from primary ciliary dyskinesia (PCD) in adulthood. METHODS: Twenty-three patients with diagnosed PCD underwent medical history aimed at recording the presence of ear, nose, and throat manifestations (ENT) and any surgical treatments. The ENT objectivity was annotated, and then patients were subjected to audiometric test, tympanometry, registration of otoacoustic emission, and vestibular evaluation. RESULTS: Otitis media with chronic middle ear effusion (OME) during childhood was reported in 52% of the subjects, no patient had undergone ear surgery, and only 2 patients had an episode of otitis in the last year. Eleven of 23 patients showed normal hearing, 11 had a conductive hearing impairment, and 1 showed a severe sensorineural hearing loss unrelated to the syndrome. The bilateral stapedial reflex was only found in all cases of normoacusia and type A tympanogram, distortion product otoacoustic emissions (DPOAE) were present in 8 patients, and no patient had vestibular alterations. CONCLUSION: Our study confirms a very frequent prevalence of OME in PCD during childhood. Careful monitoring of otological complications of the syndrome is always desirable, also given the high presence in adults of other manifestations in the upper airways, such as chronic rhinosinusitis and nasal polyposis.


Assuntos
Perda Auditiva Condutiva/epidemiologia , Síndrome de Kartagener/epidemiologia , Miringoesclerose/epidemiologia , Otite Média com Derrame/epidemiologia , Testes de Impedância Acústica , Adulto , Audiometria de Tons Puros , Doença Crônica , Feminino , Perda Auditiva Condutiva/fisiopatologia , Humanos , Síndrome de Kartagener/fisiopatologia , Masculino , Pessoa de Meia-Idade , Emissões Otoacústicas Espontâneas/fisiologia , Prevalência , Reflexo/fisiologia , Estapédio/fisiopatologia
11.
Virchows Arch ; 449(3): 320-7, 2006 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-16847683

RESUMO

We present two cases of small B-cell lymphomas of particular diagnostic interest because the histological patterns were at variance with their immunophenotype. One of these lymphomas, involving the gallbladder and duodenum, showed a marginal zone lymphoma-like (MALT type) pattern of cellular infiltration with CD5 negativity but (unexpectedly) Cyclin D1 positivity. Fluorescence in situ hybridization analysis of this case was performed because of the aberrant expression of Cyclin D1, and was clearly positive for the Cyclin D1 gene translocation. The second case, occurring in a lymph node, showed the typical growth pattern of a follicular lymphoma but it had an atypical immunophenotype, namely, expression of Cyclin D1, CD10, and Bcl2 and focally Bcl6, accompanied by a lack of CD5 and CD23. The Cyclin D1 gene translocation was detected by fluorescence in situ hybridisation (FISH), whereas c-myc and Bcl2 genes translocation were absent. Numerical chromosomal changes, which were visualized for chromosomes 8, 11, and 18 could be correlated to the aberrant immunoprofile. In this context, we discuss the diagnostic value of Cyclin D1, CD5, CD23, CD10, Bcl6 markers revealed by immunohistochemistry, as well as the significance of detection by FISH of chromosomal translocations such as t(11;14) and t(14;18). The question still remains as to whether such cases should be designated as specific lymphoma entities or reported as unclassifiable and the chromosome aberration reported.


Assuntos
Linfócitos B/patologia , Imunofenotipagem/métodos , Leucemia Linfocítica Crônica de Células B/patologia , Idoso , Linfócitos B/metabolismo , Biomarcadores Tumorais/metabolismo , Cromossomos Humanos Par 11/genética , Cromossomos Humanos Par 14/genética , Cromossomos Humanos Par 18/genética , Cromossomos Humanos Par 8/genética , Ciclina D1/genética , Ciclina D1/metabolismo , Feminino , Humanos , Hibridização in Situ Fluorescente , Leucemia Linfocítica Crônica de Células B/genética , Leucemia Linfocítica Crônica de Células B/metabolismo , Linfonodos/metabolismo , Linfonodos/patologia , Masculino , Pessoa de Meia-Idade , Translocação Genética
12.
Clin Hemorheol Microcirc ; 35(1-2): 269-72, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16899941

RESUMO

Fractal dimension of pericellular membrane of monocytes was evaluated in diabetic patients and in control subjects. Monocytes were collected from normal healthy volunteers (n = 6) and from diabetic (type 1 and type 2) patients (n = 9). Monocytes from healthy volunteers were also stimulated in vitro with the ionophore A23187 or with the oligopeptide FMLP. Monocytes, obtained by Ficoll-Hypaque, were examined with a Philips 300 transmission electron microscope. The cell contour was extracted, resized to a standard dimension and converted to a single pixel outline. Box-counting method was then applied to determine the fractal dimension. Fractal dimensions of monocytes appeared statistically increased in diabetic patients (type 1 and type 2), compared with sex- and age-matched controls (p < 0.01, p < 0.01). The mechanism underlying the observed increased complexity of pericellular membrane may be explained by the in vivo activation of the circulating monocyte in diabetes. In effect, fractal analysis of stimulated in vitro monocytes showed a significant increase of complexity of pericellular membrane, compared with their controls (p < 0.001). Our approach was able to assess and quantitatively evaluate in diabetic patients morphological modifications of the monocyte linked to its activation, offering new parameters useful to follow the effects of therapeutical procedures.


Assuntos
Membrana Celular/efeitos dos fármacos , Diabetes Mellitus Tipo 1/sangue , Diabetes Mellitus Tipo 2/sangue , Monócitos/ultraestrutura , Membrana Celular/ultraestrutura , Feminino , Fractais , Humanos , Ionóforos/farmacologia , Masculino , Microscopia Eletrônica de Varredura/métodos , Monócitos/efeitos dos fármacos , N-Formilmetionina Leucil-Fenilalanina/farmacologia , Estatísticas não Paramétricas
13.
Multidiscip Respir Med ; 10(1): 18, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26075070

RESUMO

BACKGROUND: Kartagener Syndrome (KS) is a rare autosomal recessive genetic disorder, resulting in a group of clinical manifestations, including bronchiectasis, chronic pansinusitis and situs inversus. METHODS: We hereby reviewed eight cases of this rare entity selected from patients attending our outpatients Respiratory Unit since 2006. Samples of respiratory epithelium were obtained with the method of nasal brushing and sent to a specialized center in order to be studied with electron microscopy. At least 50 cross sections of different cilia from different cells were observed in each specimen to study the axonemal structure. Electron micrographs were taken at a magnification of X 50,000 to determine the orientation of the cilia and at a magnification of X 110,000 to study the axonemal pattern. The incidence of abnormal cilia was expressed as a percentage. RESULTS: We observed different ultrastructural defects in our KS patients, including absence of outer dynein arms, absence of outer and inner dynein arms, and absence of the central pair with transposition of a peripheral doublet into the central position. Patient's follow up lasted till 2014, however two patients with more severe clinical behavior died before. CONCLUSIONS: This is a review of a case series, yet our data has shown that nasal brushing with ultrastructural pathological differentiation may be useful to identify patients with high risk and to develop more complex clinical presentations.

14.
Microbes Infect ; 12(12-13): 990-1001, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-20615478

RESUMO

The polysaccharide capsule is a major virulence factor of Streptococcus pneumoniae as it confers resistance to phagocytosis. The encapsulated serotype 4 TIGR4 strain was shown to be efficiently phagocytosed by the mouse microglial cell line BV2, whereas the type 3 HB565 strain resisted phagocytosis. Comparing survival after uptake of TIGR4 or its unencapsulated derivative FP23 in gentamicin protection and phagolysosome maturation assays, it was shown that TIGR4 was protected from intracellular killing. Pneumococcal capsular genes were up-regulated in intracellular TIGR4 bacteria recovered from microglial cells. Actual presence of bacteria inside BV2 cells was confirmed by transmission electron microscopy (TEM) for both TIGR4 and FP23 strains, but typical phagosomes/phagolysosomes were detected only in cells infected with the unencapsulated strain. In a mouse model of meningitis based on intracranic inoculation of pneumococci, TIGR4 caused lethal meningitis with an LD(50) of 2 × 10² CFU, whereas the LD(50) for the unencapsulated FP23 was greater than 107 CFU. Phagocytosis of TIGR4 by microglia was also demonstrated by TEM and immunohistochemistry on brain samples from infected mice. The results indicate that encapsulation does not protect the TIGR4 strain from phagocytosis by microglia, while it affords resistance to intracellular killing.


Assuntos
Cápsulas Bacterianas/metabolismo , Viabilidade Microbiana , Microglia/microbiologia , Fagocitose , Streptococcus pneumoniae/patogenicidade , Fatores de Virulência/metabolismo , Animais , Cápsulas Bacterianas/imunologia , Encéfalo/microbiologia , Encéfalo/patologia , Células Cultivadas , Modelos Animais de Doenças , Perfilação da Expressão Gênica , Regulação Bacteriana da Expressão Gênica , Genes Bacterianos , Imuno-Histoquímica , Dose Letal Mediana , Meningites Bacterianas , Camundongos , Microglia/imunologia , Microscopia Eletrônica de Transmissão , Streptococcus pneumoniae/imunologia , Análise de Sobrevida , Virulência , Fatores de Virulência/imunologia
16.
Ital J Pediatr ; 35(1): 24, 2009 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-19660117

RESUMO

BACKGROUND: Primary ciliary dyskinesia (PCD) is associated with pulmonary involvement that requires periodical assessment. Chest high-resolution computed tomography (HRCT) has become the method of choice to evaluate chronic lung disease, but entails exposure to ionizing radiation. Magnetic resonance imaging (MRI) has been proposed as a potential radiation-free technique in several chest disorders. Aim of our study is to evaluate whether high-field MRI is as effective as HRCT in identifying PCD pulmonary abnormalities. We also analyzed the relationships between the severity and extension of lung disease, and functional data. METHODS: Thirteen PCD patients (8 children/5 adults; median age, 15.2 yrs) underwent chest HRCT and high-field 3T MRI, spirometry, and deep throat or sputum culture. Images were scored using a modified version of the Helbich system. RESULTS: HRCT and MRI total scores were 12 (range, 6-20) and 12 (range, 5-17), respectively. Agreement between HRCT and MRI scores was good or excellent (r > 0.8). HRCT and MRI total scores were significantly related to forced vital capacity (r = -0.5, p = 0.05; and r = -0.7, p = 0.009, respectively) and forced expiratory volume at 1 second (r = -0.6, p = 0.03; and r = -0.7, p = 0.009, respectively). CONCLUSION: Chest high-field 3T MRI appears to be as effective as HRCT in assessing the extent and severity of lung abnormalities in PCD. MRI scores might be used for longitudinal assessment and be an outcome surrogate in future studies.

17.
Bioelectromagnetics ; 23(3): 230-8, 2002 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-11891753

RESUMO

The possibility that magnetic fields (MF) cause antitumor activity in vivo has been investigated. Two different experiments have been carried out on nude mice bearing a subcutaneous human colon adenocarcinoma (WiDr). In the first experiment, significant increase in survival time (31%) was obtained in mice exposed daily to 70 min modulated MF (static with a superimposition of 50 Hz) having a time average total intensity of 5.5 mT. In the second independent experiment, when mice bearing tumors were exposed to the same treatment for four consecutive weeks, significant inhibition of tumor growth (40%) was reported, together with a decrement in tumor cell mitotic index and proliferative activity. A significant increase in apoptosis was found in tumors of treated animals, together with a reduction in immunoreactive p53 expression. Gross pathology at necroscopy, hematoclinical/hematological and histological examination did not show any adverse or abnormal effects. Since pharmacological rescue of mutant p53 conformation has been recently demonstrated, the authors suggest that MF exposure may obtain a similar effect by acting on redox chemistry connected to metal ions which control p53 folding and its DNA-binding activity. These findings support further investigation aimed at the potential use of magnetic fields as anti-cancer agents.


Assuntos
Neoplasias do Colo/patologia , Magnetismo , Neoplasias/patologia , Animais , Apoptose/fisiologia , Feminino , Camundongos , Camundongos Nus , Índice Mitótico , Modelos Animais , Taxa de Sobrevida , Células Tumorais Cultivadas , Proteína Supressora de Tumor p53/metabolismo
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