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Background: Human papilloma virus (HPV) is involved in development of almost all cervical cancers, mainly through the subversion of cellular mechanisms of growth control. Fascin plays central role in subsequent cell transformation events. Fascin mediates stabilization of parallel actin bundles where cellular protrusions are formed; this represents primary stages of cell migration and metastasis. Immunohistochemical assays have shown up-regulation of fascin expression in many epithelial and non-epithelial neoplasms. Therefore, the aim of this study was to investigate HPV infection and fascin expression in samples of cervical cancer. Methods: Of 66 patients with confirmed SCC, formalin-fixed specimens, embedded in paraffin blocks were evaluated for HPV infection with nested multiplex polymerase chain reaction (NM-PCR) and for fascin expression with immunohistochemical assays. Statistical analysis was performed using Wilcoxon rank-sum test and SPSS software. A p<0.05 was considered for statistical significance. Results: Of 66 samples, 52 (78.7%) were found positive for HPV infection and fascin over-expression was shown in all squamous cell carcinoma samples. Conclusion: This study showed fascin overexpression in squamous cell carcinoma of the cervix which might be involved in metastasis of cancers induced by some types of HPV, hypothetically through attenuation of inter-cellular adhesions, and induction of cell motility.
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OBJECTIVE: Angiotensin converting enzyme (ACE) converts angiotensin I into angiotensin II. The ACE gene shows an I/D polymorphism, which correlates with ACE concentrations. The aim of this study is to evaluate the distribution of the ACE I/D genotype in children with idiopathic nephrotic syndrome (INS) and healthy controls and study the effect of this polymorphism on clinical and pathologic findings. METHODS: ACE gene I/D polymorphism of 104 patients with INS and 119 controls were determined. RESULTS: The DD, ID, and II genotypes were found in 58.7%, 22.1%, and 19.2% of the patients, and in 79.8%, 2.5%, and 17.6% of controls, respectively (p > 0.05). The ID genotype was seen more frequently in patients resistant to treatment. CONCLUSION: The observed differences with previous reports suggest the influence of the genetic background on disease course. The ACE I/D gene polymorphism's role seems to be more important in renal disease progression than susceptibility.
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Síndrome Nefrótico/genética , Peptidil-Dipeptidasa A/genética , Adolescente , Biopsia , Niño , Preescolar , Progresión de la Enfermedad , Femenino , Predisposición Genética a la Enfermedad , Genotipo , Humanos , Lactante , Masculino , Polimorfismo de Nucleótido SimpleRESUMEN
Tailgut cyst, a type of retro-rectal cyst, is a rare condition requiring evaluation for malignant transformation. We report a case of squamous cell carcinoma arising in the retro-rectal cyst, in a 51-year-old female who underwent incomplete resection of the cyst and chemo-radiotherapy, subsequently became locally recurred and metastatic.
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Background: Tuberculosis (TB) is one of the most serious public health problems worldwide which is a chronic infectious disease and is still one of the major challenges for developing countries. This study was undertaken to identify Mycobacterium TB (MTB) in clinical specimens in hospitalized patients. Methods: The study was carried out on specimens from pulmonary and extrapulmonary suspected TB patients that were admitted to one of the largest tertiary hospitals located in Tehran, Iran from 2017 to 2021. The GeneXpert MTB/rifampin (RIF) method was applied to detect MTB and RIF resistance. Characteristics of demography, clinical features, and lifestyle were obtained from medical case records registered in the hospital. Results: Of 957 specimens, 92 (9.61%) were found positive for TB by GeneXpert assay. Of positive samples, 72 (78.26%) were considered pulmonary TB, and 20 (21.73%) of them are associated with extrapulmonary involvement. Four (4.3%) positive TB cases were categorized as rifampicin-resistant. Conclusion: This study showed a relatively high incidence rate of TB in distinct types of specimens in Iranian hospitalized patients but a low level of RIF resistance.
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Mycobacterium tuberculosis , Tuberculosis Extrapulmonar , Tuberculosis , Humanos , Mycobacterium tuberculosis/genética , Irán/epidemiología , Sensibilidad y Especificidad , Tuberculosis/microbiología , Rifampin/farmacologíaRESUMEN
Background: Some studies emphasise the relationship between the herpes simplex virus (HSV) and pemphigus. Although the possible role of HSV in the pathogenesis of pemphigus and the severity of the disease is obscure, we aimed to evaluate the presence of herpes simplex viruses (HSV 1/2) in the oral lesions of patients with pemphigus vulgaris and also assess its association with disease severity and types of lesions. Methods: A retrospective study was conducted on collected data in the form of collecting paraffin blocks, slides, and relevant pathology reports and referring to patients' medical records. A questionnaire containing details on the degree of skin, scalp, and mucosal involvement (Pemphigus Disease Area Index (PDAI)) was fulfiled. The immunoassay result was also collected to check the anti-desmoglein 3 and 1 antibodies (using ELISA technique). Results: In this study, 52 patients of pemphigus vulgaris with oral lesions (case) and 52 patients with oral lesions not related to the disease (control) were evaluated. HSV1 was detected in 13.5% of oral pemphigus lesions and 1.9% of the control group (p = 0.0598). There were no positive cases of HSV2 in either group. There was no significant association between the positivity of HSV1 and the site of lesions (p = 1.00) or disease severity (p = 0.28). However, we found a strong correlation between the PDAI disease severity score with the titre of the AntiDsg3 antibody (r = 0.487, p = 0.001) and AntiDsg1 antibody (r = 0.309, p = 0.026). Conclusion: This study demonstrated a significant prevalence of HSV1 in oral pemphigus lesions, and acyclovir therapy may play a significant role in managing these patients. However, HSV's role in the pathogenesis of pemphigus vulgaris cannot be clearly determined.
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Background & Objective: Iran is located in the esophageal cancer geographical belt. As multiple genetic alterations are responsible for the molecular pathogenesis of esophageal squamous cell cancer (ESCC), the role and frequency of HER2 expression, MMR deficiency, and PI3KCA mutation are not well defined. Methods: We carried out HER2/neu expression, dMMR/MSI high, and PI3KCA mutation analysis in specimens of patients with ESCC. We accessed archival tissue blocks related to specimens of 68 ESCC cases at the time of surgery following neoadjuvant chemoradiation. These patients underwent surgery during 2013-2018 at the Cancer Institute of Iran affiliated with the Tehran University of Medical Sciences in Tehran. Results: None of the patients showed HER2 expression, dMMR/MSI high, or PI3K mutations. Conclusion: dMMR/MSI-H and PI3KCA mutation and HER2 expression may not be reliable andfrequent targets for systemic therapy in patients with esophageal SCC.
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INTRODUCTION: BK virus nephropathy (BKVN) is an important complication of kidney transplantation and kidney biopsy remains the gold standard for its diagnosis. Urine/serum polymerase chain reaction (PCR) is a more sensitive diagnostic method, although it has some potential limitations. METHODS: This study enrolled all kidney transplant recipients who underwent kidney transplant biopsy, collected from three medical centers. Urine and serum PCR results of the patients were also collected from the molecular laboratories. The cut-off value for positive viral DNA load in serum and urine were > 104 and > 107 copies/mL, respectively. Sensitivity, specifity, positive and negative predictive values (PPV, NPV) and cut off values for PCR results were compared with pathologic diagnosis among laboratories. RESULTS: Among 369 biopsy samples, 33 (8.9%) had definite diagnosis of BKVN. PCR results were available for 138 cases. Three patients with definite BKVN had negative PCR results. In 22 patients, PCR was positive without evidence of BKVN. The overall sensitivity, specificity, PPV and NPV of PCR for detecting BKVN, based on a unique cut-off value, were 88, 81, 51, and 97%; respectively. The overall accuracy of PCR in all laboratories was high (82 to 86%), however significant inter-laboratory differences in sensitivity and specificity was found . A 2-log difference in threshold value for positive results was observed in one laboratory. CONCLUSION: PCR may show a significant variability between different laboratories. Interpretation of PCR results using a single cut-off value for all laboratories, may decrease the sensitivity for the diagnosis and screening of BKVN. DOI: 10.52547/ijkd.7143.
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Virus BK , Trasplante de Riñón , Nefritis Intersticial , Humanos , Virus BK/genética , Irán , Trasplante de Riñón/efectos adversos , Receptores de TrasplantesRESUMEN
HER2-positive metastatic breast cancer is much less frequent than other subgroups of breast cancer. Treatment options for this cancer are mostly limited to systemic chemotherapy, which leads to moderate improvements. Targeted therapy against malignant breast cancer requires the identification of reliable biomarkers for personalized medicine to obtain the maximum benefit of this therapy. Any mutations in the TP53 signaling pathway can be considered as a significant causative factor of breast cancer, for which the identification of target genes plays an important role in selecting the appropriate treatment. The use of personalized gene expression profiling could be valuable to find the direct target of the treatment in this case. The present study assessed the genetic profile of an HER2-positive metastatic breast cancer patient (with a liver metastasis) and figured out a complete and sustained response to bevacizumab. According to the results of next-generation sequencing (NGS) analysis, the patient's genetic profile showed an increased expression of p4EBP1 and PTEN and the activation of the mTOR signaling pathway with a mutation in the TP53 gene. Based on the common treatment of similar profiling, we administrated bevacizumab/Taxol/Gemzar chemotherapy up to six courses. Accordingly, as the response to treatment was revealed by reducing the volume of the liver metastasis from 4 to 1.4 cm, metastasectomy was performed as a complementary treatment. Hence, personalized gene expression profiling not only is useful for targeted therapy but also could be recommended to avoid prescription of non-responsive drugs.
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BACKGROUND & OBJECTIVE: Nowadays, actin-binding proteins such as Villin and Gelsolin have been considered to be associated with aggressive tumors. This study mainly aims to determine the relationship between Gelsolin and Villin genes expression and metastasis of axillary lymph nodes in patients with breast cancer. METHODS: The included population consisted of 40 confirmed cases of female breast cancer (including 20 patients with breast cancer along with axillary lymph node metastasis and 20 patients without axillary lymph node metastasis). Expression of Villin and Gelsolin genes was evaluated using Real-time PCR and pre-designed primers. RESULTS: The mean expression level of Villin in groups with and without axillary lymph node metastasis was 3.33±1.35 and 0.87±0.88, respectively (P<0.001). The mean Gelsolin expression levels in both groups (with and without axillary lymph node metastasis) were 4.13±2.40 and 1.00±0.35, respectively (P<0.001). The significant relationships were independent of individuals' age. CONCLUSION: Patients with axillary lymph node metastasis may express significant higher level of Villin and Gelsolin genes.
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BACKGROUND: Iron deficiency is the most common cause of anemia in children. Recently there has been evidence to suggest a relationship between Helicobacter pylori gastritis and iron deficiency anemia. Because both H. pylori infection and iron-deficiency anemia are common in children, we studied any correlation between H. pylori infection and iron-deficiency anemia in children. METHOD: In a case-control study at the Children's Medical Center Hospital, 100 children with H. pylori infection and 109 children without infection according to histology were evaluated. Iron-deficiency anemia was diagnosed when serum ferritin and hemoglobin levels were less than adjusted values for age and sex. RESULTS: There were 111 boys and 98 girls with a median age of 7.1 years. The main symptom was abdominal pain in H. pylori-infected and non-infected patients. Frequency of H. pylori infection in anemic and non-anemic patients was nearly similar (43.9 and 50.4%, respectively). Among patients with H. pylori, 36% had anemia and in patient without H. pylori infection, its frequency was 42.2% (p = 0.59). Among patients with H. pylori, 19% had iron-deficiency anemia and in patients without H. pylori infection, its frequency was 21.1% (p = 0.7). Among patients with H. pylori, the difference between the severity of gastritis in those with anemia and those without anemia was not statistically significant (p = 0.382) and no correlation was found between degree of H. pylori colonization and anemia. CONCLUSIONS: Our results do not support the proposal that H. pylori infection is associated with iron-deficiency anemia in children. Further studies emphasizing the socioeconomic status of children, evaluation of strains of H. pylori, and posttreatment measurement of serum iron and serum ferritin are necessary to show the possible association.
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Anemia/epidemiología , Anemia/microbiología , Infecciones por Helicobacter/epidemiología , Infecciones por Helicobacter/microbiología , Anemia/complicaciones , Niño , Preescolar , Femenino , Infecciones por Helicobacter/complicaciones , Humanos , MasculinoRESUMEN
Recent advances in sequencing technologies have enabled us to scrutinize the versatile underlying mechanisms of cancer more precisely. However, adopting these new sophisticated technologies is challenging for clinical labs as it involves complex workflows, and requires validation for diagnostic purposes. The aim of this work is towards the analytical validation of a next generation sequencing (NGS) panel for cancer hotspot mutation analysis. Characterized formalin-fixed paraffin-embedded (FFPE) samples including biopsy specimens and cell-lines were examined by NGS methods utilizing the Ion Torrent™ Oncomine™ Focus DNA Assay and the PGM™ platform. Important parameters for somatic mutations including the threshold for differentiation of a positive and a negative result, coverage, sensitivity, specificity, and limit of detection (LoD) were analyzed. Variant calls with coverage of <100x were found to be inaccurate. The limit of detection for identifying hotspot mutations was determined to be 4.3%. The sensitivity and specificity of the method were 96.1% and 97.8% respectively. No statistically significant difference was found between different gene targets in terms of performance of hotspot frequency measurement for the subset tested. In every validation study, the number of samples, the manner of sample selection, and the number and type of variants play a role in the outcome. Therefore, these parameters should be assessed according to the clinical needs of each laboratory undertaking the validation.
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Análisis Mutacional de ADN/métodos , Secuenciación de Nucleótidos de Alto Rendimiento/normas , Mutación , Análisis Mutacional de ADN/normas , Humanos , Reproducibilidad de los Resultados , Sensibilidad y EspecificidadRESUMEN
There is plenty of substantial evidence to support anti-tumor activity of viruses. Adeno-associated virus (AAV) may interact with human papillomavirus (HPV) to modify the risk of cervical neoplasia. The seroprevalence of AAV among women with cervical cancer has been reported to be lower than healthy ones. In spite of this finding, detection of AAV DNA in cervical biopsies does not entirely support the inverse association between AAV seropositivity and cervical cancer. This association is still controversial and requires more thorough evaluation in different countries. The aim of this case-control study was to find the prevalence of AAV and HPV DNA sequences in Iranian women with and without cervical cancer to assess the probable association of AAV infection and cervical cancer. In this study, paraffin-embedded tissue samples of 61 cervical cancer cases and 50 healthy controls (HCs) were investigated for AAV and HPV DNA by semi-nested and nested PCRs respectively. AAV DNA was detected in 7 cases (14%) of HCs and 9 specimens (14.8%) of case group. According to the branching in the phylogenetic tree, AAV2 was the only type detected in this study. Moreover, HPV DNA was detected in 8 cases (16%) of HCs and 44 specimens (72.13%) of case group. In conclusion, a low proportion of cervical biopsies from Iranian women contained AAV-2 genome. No significant difference in correlation between HPV and cervical cancer in presence or absence of AAV genome in cervix was found.
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Dependovirus/aislamiento & purificación , Papillomaviridae/aislamiento & purificación , Infecciones por Papillomavirus/epidemiología , Infecciones por Parvoviridae/epidemiología , Neoplasias del Cuello Uterino/epidemiología , Adulto , Estudios de Casos y Controles , ADN Viral/genética , Dependovirus/genética , Femenino , Humanos , Irán/epidemiología , Persona de Mediana Edad , Papillomaviridae/genética , Infecciones por Papillomavirus/virología , Adhesión en Parafina , Infecciones por Parvoviridae/virología , Filogenia , Reacción en Cadena de la Polimerasa , Prevalencia , Neoplasias del Cuello Uterino/virologíaRESUMEN
Neuromyelitis optica is an inflammatory demyelinating disease (IDD) of the CNS, which mainly affects optic nerve and spinal cord. Autoantibodies against aquaporin-4 also known as NMO-IgG have been implicated in the pathogenesis of NMO. We evaluated the sensitivity and specificity of NMO-IgG assay for diagnosing NMO patients and differentiating them from MS patients and those with undifferentiated IDD with overlap symptoms.Eligibility of patients with demyelinating disorders was evaluated based on physical examination, laboratory and imaging studies. Thirty four definite NMO patients (disregarding NMO-IgG status), 34 multiple sclerosis (MS) patients with a history of optic neuritis (ON) or myelitis that were matched for age and disease activity and 44 patients with ON or myelitis attacks fulfilling neither criteria of MS or NMO (NMO spectrum) were selected as undifferentiated group. NMO-IgG was measured in the serum of the included patients by cell-based indirect immunofluorescence assay (IFA). NMO antibody was positive in 11 (32.3%), and 4 (9.09%) patients in NMO and undifferentiated groups, but was undetctable in MS patients. NMO antibody was 32% (95%Cl: 19-49%) sensitive in detecting NMO patients. Its specificity in differentiating NMO from MS subjects was 100 % (95% Cl: 90-!00%). NMO antibody was 95% (95% Cl: 0.88-0.98) specific in differentiating NMOs from other demyelinating diseases. Our results showed that although NMO antibody is highly specific for NMO, current method of measuring it with cell-based IFA is not highly sensitive for diagnosing NMO patients.
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Autoanticuerpos/sangre , Enfermedades Autoinmunes Desmielinizantes SNC/diagnóstico , Inmunoglobulina G/sangre , Neuromielitis Óptica/diagnóstico , Adulto , Enfermedades Autoinmunes Desmielinizantes SNC/sangre , Diagnóstico Diferencial , Femenino , Técnica del Anticuerpo Fluorescente Indirecta/métodos , Humanos , Irán , Masculino , Neuromielitis Óptica/sangre , Neuromielitis Óptica/inmunología , Sensibilidad y Especificidad , Estudios SeroepidemiológicosRESUMEN
BACKGROUND: Cervical cancer is the leading cause of death from cancer in under-developed countries. Human papilloma virus (HPV) 16 and 18 are the most prevalent types associated with carcinogenesis in the cervix. Conventional Polymerase Chain Reaction (PCR), type-specific and consensus primer-based PCR followed by sequencing, Restriction Fragment Length Polymorphism (RFLP) or hybridization by specific probes are common methods for HPV detection and typing. In addition, some researchers have developed a multiplex PCR for simultaneous detection and typing of different HPVs. OBJECTIVES: The aim of the present study was to investigate the prevalence of HPV infection and its types in cervical Squamous Cell Carcinoma (SCC) using the Nested Multiplex PCR (NMPCR) assay. PATIENTS AND METHODS: Sixty-six samples with histologically confirmed SCC were evaluated. Total DNA was isolated by phenol-chloroform extraction and ethanol precipitation. Nested multiplex PCR was performed with first-round PCR by GP-E6/E7 consensus primers for amplification of the genomic DNA of all known mucosal HPV genotypes and second-round PCR by type-specific multiplex PCR primer cocktails. RESULTS: Human papilloma virus infection was detected in 78.8% of samples, with the highest prevalence of HPV 16 (60.6%) while concurrent infections with two types was detected in 10.6%. CONCLUSIONS: The NMPCR assay is more convenient and easy for analysis of results, which is important for fast diagnosis and patient management, in a type-specific manner.
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BACKGROUND: Early post-transplantation alterations in liver tests are caused by a variety of etiologies including rejection, biliary or vascular complications, and preservation/reperfusion injury (PRI). OBJECTIVES: The aim of this study was to show the correlation between histopathologic changes of PRI and the alterations in liver tests in the early post-transplantation period. MATERIALS AND METHODS: Between April 2013 and August 2014, histopathologic findings of protocol, time-zero, Tru-Cut, liver needle biopsies were evaluated in 94 cases of cadaveric liver transplantation. The histopathologic changes included ballooning degeneration, micro- and macro-vesicular steatosis, bilirubinostasis, apoptotic cells, bile plugs and neutrophilic infiltration. These histopathologic changes were compared with the early (15 days) post-transplantation liver laboratory findings. RESULTS: Clinico-pathologic evaluation of all 94 cases was done by assessment of PRI findings in time-zero biopsies and possible causes of allograft injury were appraised. In 21 patients, a specific cause for allograft injury was found including rejection and/or surgical complications. In the remaining 73 cases, there was no specific cause for allograft injury and histopathologic findings of time-zero liver needle biopsies supported PRI. We classified liver laboratory tests alterations as: hepatocellular damage (elevation of transaminases and lactate dehydrogenase), cholestatic damage (elevation of alkaline phosphatase and total bilirubin) and mixed. Hepatocellular and cholestatic alterations in liver function tests were associated with the presence of marked apoptotic bodies and neutrophilic aggregates in time zero biopsies, respectively. On the other hand, macrovesicular steatosis was dominantly associated with mixed (hepatocellular and cholestatic) laboratory alterations of liver tests. CONCLUSIONS: Any discrepancy between histopathologic changes in time-zero biopsies and pattern of early liver laboratory alterations may be considered as a warning for causes other than PRI.
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BACKGROUND: Cervical cancer is the fourth most common cancer among women worldwide. Organized cervical screening and vaccination against human papilloma virus (HPV) have been successful interventions for prevention of invasive cervical cancer (ICC). Because of cultural and religious considerations, ICC has low incidence in Iran and many other Muslim countries. There is no organized cervical screening in these countries. Therefore, ICC is usually diagnosed in advanced stages with poor prognosis in these countries. We performed a priority setting exercise and suggested priorities for prevention of ICC in this setting. METHODS: We invited experts and researchers to a workshop and asked them to list important suggestions for ICC prevention in Iran. After merging similar items and removing the duplicates, we asked the experts to rank the list of suggested items. We used a strategy grid and Go-zone analysis to determine final list of priorities for ICC prevention in Iran. RESULTS: From 26 final items suggested as priorities for prevention of ICC, the most important priorities were developing national guidelines for cervical screening and quality control protocol for patient follow-up and management of precancerous lesions. In addition, we emphasized considering insurance coverage for cervical screening, public awareness, and research priorities, and establishment of a cervical screening registry. CONCLUSION: A comprehensive approach and implementation of organized cervical screening program is necessary for prevention of ICC in Iran and other low incidence Muslim countries. Because of high cost for vaccination and low incidence of cervical cancer, we do not recommend HPV vaccination for the time being in Iran.
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Detección Precoz del Cáncer/métodos , Prioridades en Salud/organización & administración , Neoplasias del Cuello Uterino/diagnóstico , Concienciación , Análisis Costo-Beneficio , Detección Precoz del Cáncer/economía , Femenino , Política de Salud , Humanos , Incidencia , Reembolso de Seguro de Salud , Irán/epidemiología , Guías de Práctica Clínica como Asunto , Vigilancia en Salud Pública , Control de Calidad , Sistema de Registros , Neoplasias del Cuello Uterino/epidemiologíaRESUMEN
Human papillomavirus (HPV) has also been suggested as an etiology of esophageal squamous cell carcinoma (SCC). The aim of this study was to investigate the prevalence of HPV infection in esophageal SCCs in our region with strict contamination control to prevent false positive results. Thirty cases of esophageal squamous cell carcinomas were chosen by simple random selection in a period of two years. PCR for target sequence of HPV L1 gene was performed on nucleic acid extracted from samples by means of GP5+/GP6+ primers. All tissue samples in both case and control groups were negative for HPV-DNA. Although the number of cases in this study was limited, the contribution of HPV in the substantial number of esophageal SCCs in our region is unlikely.
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Carcinoma de Células Escamosas/virología , Neoplasias Esofágicas/virología , Infecciones por Papillomavirus/epidemiología , Adulto , Anciano , Anciano de 80 o más Años , Carcinoma de Células Escamosas/patología , Estudios de Casos y Controles , Neoplasias Esofágicas/patología , Femenino , Humanos , Irán/epidemiología , Metástasis Linfática , Masculino , Persona de Mediana Edad , Clasificación del Tumor , Invasividad Neoplásica , Reacción en Cadena de la Polimerasa , Prevalencia , Factores de RiesgoRESUMEN
OBJECTIVE: Lithium improves locomotor scores after spinal cord injury (SCI) in rats. However, the underlying mechanisms are unknown. Herein, we assess the role of nitric oxide (NO) in this action. METHODS: The first set of experiments were performed to determine a dose of lithium that effectively improves locomotor scores in rats with SCI. Therefore, rats received different doses of lithium chloride (1, 4, 10, and 20 mg/kg intraperitoneally) or saline 1 hour before SCI. In the next step, the role of NO in the effect of lithium on SCI was investigated. For this purpose, rats were co-treated with an effective dose of lithium (20 mg/kg 1 hour before SCI) and a noneffective dose of Nω-nitro-L-arginine methyl ester (L-NAME, a nonselective NO synthase inhibitor; 15 mg/kg intraperitoneally 30 minutes before SCI). SCI was induced by compressing the T9 spinal segment with an aneurysmal clip for 60 seconds in anesthetized rats. Locomotor scores were determined at 1, 3, 5, 7, 14, 21, and 28 days after SCI. Plasma lithium levels were measured 12 hours after SCI. Spinal histopathologies were examined 30 days after SCI. RESULTS: Lithium (20 mg/kg) significantly improved locomotor scores and decreased histopathologic spinal damage. l-NAME (15 mg/kg) reversed the beneficial effects of lithium. The 20-mg/kg dose of lithium resulted in a 0.68 ± 0.02 mEq/L plasma lithium concentration, which is lower than the therapeutic level in humans (0.8-1.2 mEq/L). CONCLUSION: Lithium protects against SCI through an NO-dependent mechanism.