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1.
Exp Clin Transplant ; 20(7): 702-705, 2022 07.
Article in English | MEDLINE | ID: mdl-33272154

ABSTRACT

Dyskeratosis congenita, a rare genetic disorder typified by progressive bone marrow failure, is classically characterized by the triad of abnormal skin pigmentation, nail dystrophy, and oral leukoplakia; however, it is a multisystem disease. Although hepatic involvement occurs in about 7% of patients with dyskeratosis congenita, end-stage liver disease is rare. Treatment of dyskeratosis congenita generally involves hematopoietic stem cell transplant. For patients with hepatic failure, liver transplant can be an option. Here, we describe a case of a patient with dyskeratosis congenita who presented with liver failure and pulmonary failure, precluding him from hematopoietic stem cell transplant. After liver transplant, the patient had significant improvements in pulmonary function and transfusion requirements, allowing the patient to qualify for hematopoietic stem cell transplant. Although hematopoietic stem cell transplant is typically the first step in the management of dyskeratosis congenita, for patients with severe hepatic manifestations of the disease, a liver transplant first approach may result in better disease management.


Subject(s)
Dyskeratosis Congenita , Liver Transplantation , Dyskeratosis Congenita/complications , Dyskeratosis Congenita/diagnosis , Dyskeratosis Congenita/genetics , Humans , Leukoplakia, Oral/complications , Liver , Liver Transplantation/adverse effects , Male , Treatment Outcome
2.
Arch Pathol Lab Med ; 146(1): 84-91, 2022 01 01.
Article in English | MEDLINE | ID: mdl-33769446

ABSTRACT

CONTEXT.­: Pancreatic adenocarcinoma is the third leading cause of cancer death in the United States. Surgery remains the mainstay of treatment, and frozen section analysis is used to confirm diagnosis and determine resectability and margin status. OBJECTIVE.­: To evaluate use and accuracy of frozen section and how diagnosis impacts surgical procedure. DESIGN.­: We reviewed patients with planned pancreatic resections between January 2014 and March 2019 with at least 1 frozen section. Pathology reports including frozen sections, preoperative cytology, and operative notes were reviewed. Frozen sections were categorized by margin, primary pancreatic diagnosis, metastasis, or vascular resectability. The deferral and error rates and surgeons' response were noted. RESULTS.­: We identified 898 planned pancreatic resections and 221 frozen sections that were performed on 152 cases for 102 margins, 94 metastatic lesions, 20 primary diagnoses, and 5 to confirm vascular resectability. The diagnosis was deferred to permanent sections in 13 of 152 cases (8.6%) on 16 of 221 frozen sections (7.2%): 6 for metastasis, 8 for margins, and 2 for primary diagnosis. Discrepancies/errors were identified in 4 of 152 cases (2.6%) and 4 of 221 frozen sections (1.8%). Surgeons' responses were different than expected in 8 of 221 frozen sections (3.6%), but their actions were explained by other intraoperative findings in 6 of 8. CONCLUSIONS.­: Frozen section remains an important diagnostic tool used primarily for evaluation of margins and metastasis during pancreatectomy. In most cases, a definitive diagnosis is rendered, with occasional deferrals and few errors. Intraoperative findings explain most cases where surgeons act differently than expected based on frozen section diagnosis.


Subject(s)
Adenocarcinoma , Pancreatic Neoplasms , Adenocarcinoma/diagnosis , Adenocarcinoma/surgery , Diagnostic Errors , Frozen Sections , Humans , Pancreas/surgery , Pancreatectomy , Pancreatic Neoplasms/diagnosis , Pancreatic Neoplasms/surgery , Retrospective Studies
3.
Cardiovasc Pathol ; 46: 107202, 2020.
Article in English | MEDLINE | ID: mdl-32062109

ABSTRACT

Nivolumab (PD-1 inhibitor) and Ipilimumab (CTLA-34 inhibitor) are both commonly used immune checkpoint inhibitor therapies for various cancers. Various adverse events are associated with these therapies, including hepatitis, nephritis, dermatitis, and myocarditis. It is believed these adverse events occur in part because modified cellular receptors lead to enhanced CD4 and CD8 lymphoproliferation. These events usually occur after several months and rounds of treatment. Here we present a case of an 81-year-old male with recurrent renal cell carcinoma (RCC) who experienced myocarditis after only a single dose of combination therapy with Nivolumab and Ipilimumab. He presented with elevated troponins and a third-degree heart block; three days after admission he died. Histologic examination revealed a predominance of CD3 T cells (CD4 > CD8) and CD68 macrophages, with occasional CD20 B cells. C4d staining was negative in the interstitial capillaries, suggesting that antibody-mediated injury of endothelial cells did not play a significant role in the pathogenesis of this myocarditis. Additional studies ruled out an infectious etiology. Immune checkpoint inhibitors are increasingly more common, and it is important clinicians are aware patients can present with myocarditis early in the course of treatment.


Subject(s)
Antineoplastic Agents, Immunological/adverse effects , Antineoplastic Combined Chemotherapy Protocols/adverse effects , Carcinoma, Renal Cell/drug therapy , Ipilimumab/adverse effects , Kidney Neoplasms/drug therapy , Myocarditis/chemically induced , Nivolumab/adverse effects , Programmed Cell Death 1 Receptor/antagonists & inhibitors , Acute Disease , Aged, 80 and over , Antineoplastic Agents, Immunological/administration & dosage , Antineoplastic Combined Chemotherapy Protocols/administration & dosage , Carcinoma, Renal Cell/immunology , Carcinoma, Renal Cell/secondary , Fatal Outcome , Humans , Ipilimumab/administration & dosage , Kidney Neoplasms/immunology , Kidney Neoplasms/pathology , Male , Myocarditis/immunology , Myocarditis/pathology , Myocardium/immunology , Myocardium/pathology , Nivolumab/administration & dosage
4.
Br J Neurosurg ; 34(5): 528-533, 2020 Oct.
Article in English | MEDLINE | ID: mdl-30836020

ABSTRACT

Introduction: Pituitary carcinomas are poorly understood, rare entities. They are distinguished from adenomas not by histopathological features but rather by the presence of metastases.Objective: We discuss the diagnosis, mechanism of dissemination and pathogenesis based on a review of the literature and illustrated by a singular case.Case Report: A 59-year-old male presented with a dural-based posterior fossa lesion. He had been diagnosed with a pituitary chromophobe adenoma 43 years earlier that was treated at the time with surgery and radiation therapy. A presumptive diagnosis of a radiation-induced meningioma was made and surgery was recommended. At surgery the tumour resembled a pituitary adenoma. Histopathology, laboratory findings, and the patient's medical history confirmed the final diagnosis of a prolactin-secreting pituitary carcinoma. To our knowledge, this is the longest reported interval between the pituitary adenoma and metastatic lesion diagnosis (43 years).Conclusion: Management should be tailored to individual patient and may include a combination of treatments (surgery, radiation therapy, chemotherapy, and hormone-targeted therapy). Functionally active tumours may be monitored with hormone levels as tumour markers.


Subject(s)
Adenoma , Neoplasms, Radiation-Induced , Pituitary Neoplasms , Adenoma/diagnosis , Adenoma/surgery , Humans , Male , Middle Aged , Pituitary Neoplasms/diagnostic imaging , Pituitary Neoplasms/surgery
5.
Gac Med Mex ; 155(5): 473-480, 2019.
Article in English | MEDLINE | ID: mdl-31695222

ABSTRACT

INTRODUCTION: Gliomas are neoplasms with high recurrence and mortality. Due to the difficulty to apply the World Health Organization (2016) classification, developing countries continue to use histological evaluation to diagnose and classify these neoplasms. OBJECTIVE: To develop a semi-quantitative scale to numerically grade gliomas morphological characteristics. METHOD: A cohort of patients with gliomas was assessed and followed for 36 months. Tumor tissue sections were analyzed and graded, including aspects such as cell line, cellularity, nuclear pleomorphism, mitosis, endothelial hyperplasia, hypoxic changes, apoptotic bodies, necrosis, hemorrhage and proliferation index. RESULTS: 58 cases were analyzed. Low-grade gliomas median score was 12 points (9 and 13.5 for percentiles 25 and 75, respectively), whereas for high-grade gliomas it was 17 points (16 and 20.5 for percentiles 25 and 75, respectively) (p < 0.0001). Thirty-six-month survival of patients with low (13/17) and high grade gliomas (6/41) was also significantly different (p < 0.0001). CONCLUSIONS: The semi-quantitative morphological scale allows an objective evaluation of gliomas, with an adequate correlation between the score, tumor grade and survival time.


INTRODUCCIÓN: Los gliomas son neoplasias con alta recurrencia y mortalidad. Por la dificultad para aplicar la clasificación de la Organización Mundial de la Salud (2016), los países en desarrollo siguen utilizando la evaluación histológica para diagnosticarlos y clasificarlos. OBJETIVO: Desarrollar una escala semicuantitativa para calificar numéricamente las características morfológicas de los gliomas. MÉTODO: Cohorte de pacientes con gliomas evaluada y seguida durante 36 meses. Se analizaron y calificaron cortes del tejido tumoral, incluyendo aspectos como estirpe celular, celularidad, pleomorfismo nuclear, mitosis, hiperplasia endotelial, cambios hipóxicos, cuerpos apoptóticos, necrosis, hemorragia e índice de proliferación. RESULTADOS: Se analizaron 58 casos. La mediana de la calificación de los gliomas de bajo grado fue de 12 puntos (percentiles 25 y 75 de 9 y 13.5, respectivamente) y la de los gliomas de alto grado fue de 17 puntos (percentiles 25 y 75 de 16 y 20.5, ­respectivamente) (p < 0.0001). La supervivencia a 36 meses de los pacientes con gliomas de bajo (13/17) y alto grado (6/41) también fue significativamente diferente (p < 0.0001). CONCLUSIONES: La escala morfológica semicuantitativa permite una evaluación objetiva de los gliomas, con una adecuada correlación entre la calificación, el grado del tumor y el tiempo de supervivencia.


Subject(s)
Brain Neoplasms/pathology , Glioma/pathology , Adult , Brain Neoplasms/classification , Brain Neoplasms/mortality , Cohort Studies , Female , Glioma/classification , Glioma/mortality , Humans , Male , Middle Aged , Neoplasm Grading/statistics & numerical data
6.
Gac. méd. Méx ; 155(5): 439-446, Sep.-Oct. 2019. tab, graf
Article in English | LILACS | ID: biblio-1286540

ABSTRACT

Introduction: Gliomas are neoplasms with high recurrence and mortality. Due to the difficulty to apply the World Health Organization (2016) classification, developing countries continue to use histological evaluation to diagnose and classify these neoplasms. Objective: To develop a semi-quantitative scale to numerically grade gliomas by its morphological characteristics. Method: A cohort of patients with gliomas was assessed and followed for 36 months. Tumor tissue sections were analyzed and graded, including aspects such as cell line, cellularity, nuclear pleomorphism, mitosis, endothelial hyperplasia, hypoxic changes, apoptotic bodies, necrosis, hemorrhage and proliferation index. Results: 58 cases were analyzed. Low-grade gliomas median score was 12 points (9 and 13.5 for percentiles 25 and 75, respectively), whereas for high-grade gliomas it was 17 points (16 and 20.5 for percentiles 25 and 75, respectively) (p < 0.0001). Thirty-six-month survival of patients with low (13/17) and high grade gliomas (6/41) was also significantly different (p < 0.0001). Conclusions: The semi-quantitative morphological scale allows an objective evaluation of gliomas, with an adequate correlation between the score, tumor grade and survival time.


Subject(s)
Humans , Male , Female , Adult , Middle Aged , Brain Neoplasms/pathology , Glioma/pathology , Oligodendroglioma/mortality , Oligodendroglioma/pathology , Astrocytoma/mortality , Astrocytoma/pathology , Brain Neoplasms/classification , Brain Neoplasms/mortality , Survival Analysis , Cohort Studies , Glioblastoma/mortality , Glioblastoma/pathology , Ependymoma/mortality , Ependymoma/pathology , Neoplasm Grading , Glioma/classification
7.
Int J Gynecol Cancer ; 29(1): 113-118, 2019 01.
Article in English | MEDLINE | ID: mdl-30640692

ABSTRACT

OBJECTIVE: Endometrial carcinoma (EC) with deficient mismatch repair (dMMR) protein has been reported to have increased tumor infiltrating lymphocytes (TILs) and programed cell death ligand-1 (PD-L1) expression. TILs and PD-L1 expression are compared between two main types of dMMR ECs (epigenetic dMMR due to MLH1 promoter methylation vs mutated dMMR due to genetic mutation). METHODS: Immunohistochemistry for PD-L1 was performed in triplicate on tissue microarray sections. TILs were semi-quantitatively evaluated on whole-slide images of whole histologic sections. The clinicopathologic characteristics together with PD-L1 expression and TILs were analyzed between mutated and epigenetic dMMR ECs. RESULTS: Of the 162 dMMR ECs identified, 126 had epigenetic dMMR and 36 had mutated dMMR. Univariate analysis demonstrated mutated dMMR ECs showed younger age, less myometrium invasion of >50%, less lymphovascular invasion, and more TILs than epigenetic dMMR ECs. Multivariate analysis demonstrated significantly younger age and more TILs in mutated dMMR ECs than in epigenetic ECs. PD-L1 expression did not show any significant difference between these two groups. Seventeen (13.5%) patients with epigenetic dMMR EC had recurrence and 13 (10.3%) patients died of disease. In contrast, only one patient with mutated dMMR EC had recurrence (3%) and died of disease (3%). CONCLUSION: ECs with mutated dMMR demonstrated significantly increased TILs than ECs with epigenetic dMMR, suggesting a stronger immune reaction and potential response to immunotherapy in these tumors.


Subject(s)
B7-H1 Antigen/metabolism , Biomarkers, Tumor/analysis , DNA Repair Enzymes/deficiency , Endometrial Neoplasms/pathology , Lymphocytes, Tumor-Infiltrating/immunology , Myometrium/pathology , Neoplasm Recurrence, Local/pathology , Adult , Aged , Aged, 80 and over , B7-H1 Antigen/genetics , DNA Repair Enzymes/genetics , Endometrial Neoplasms/immunology , Endometrial Neoplasms/metabolism , Female , Follow-Up Studies , Humans , Middle Aged , Mutation , Myometrium/immunology , Myometrium/metabolism , Neoplasm Invasiveness , Neoplasm Recurrence, Local/immunology , Neoplasm Recurrence, Local/metabolism , Prognosis , Survival Rate
8.
Gac Med Mex ; 155(5): 439-446, 2019.
Article in English | MEDLINE | ID: mdl-32091031

ABSTRACT

INTRODUCTION: Gliomas are neoplasms with high recurrence and mortality. Due to the difficulty to apply the World Health Organization (2016) classification, developing countries continue to use histological evaluation to diagnose and classify these neoplasms. OBJECTIVE: To develop a semi-quantitative scale to numerically grade gliomas by its morphological characteristics. METHOD: A cohort of patients with gliomas was assessed and followed for 36 months. Tumor tissue sections were analyzed and graded, including aspects such as cell line, cellularity, nuclear pleomorphism, mitosis, endothelial hyperplasia, hypoxic changes, apoptotic bodies, necrosis, hemorrhage and proliferation index. RESULTS: 58 cases were analyzed. Low-grade gliomas median score was 12 points (9 and 13.5 for percentiles 25 and 75, respectively), whereas for high-grade gliomas it was 17 points (16 and 20.5 for percentiles 25 and 75, respectively) (p < 0.0001). Thirty-six-month survival of patients with low (13/17) and high grade gliomas (6/41) was also significantly different (p < 0.0001). CONCLUSIONS: The semi-quantitative morphological scale allows an objective evaluation of gliomas, with an adequate correlation between the score, tumor grade and survival time.


Subject(s)
Brain Neoplasms/pathology , Glioma/pathology , Adult , Astrocytoma/mortality , Astrocytoma/pathology , Brain Neoplasms/classification , Brain Neoplasms/mortality , Cohort Studies , Ependymoma/mortality , Ependymoma/pathology , Female , Glioblastoma/mortality , Glioblastoma/pathology , Glioma/classification , Glioma/mortality , Humans , Male , Middle Aged , Neoplasm Grading , Oligodendroglioma/mortality , Oligodendroglioma/pathology , Survival Analysis
9.
Am J Clin Pathol ; 149(2): 98-104, 2018 Jan 29.
Article in English | MEDLINE | ID: mdl-29365030

ABSTRACT

OBJECTIVES: Early and accurate diagnosis remains crucial in the therapeutic management of invasive central nervous system fungal infections. Different molds have intrinsic resistance to antifungal agents; thus, morphologic differentiation is helpful to clinicians. METHODS: Using three examples, we present a guide on how to approach neuropathology specimens where hyphae are identified on initial histologic examination. RESULTS: Hyphae can be classified into three basic groups: hyaline pauciseptated, hyaline septated, and pigmented or dematiaceous. The hyaline pauciseptated group includes the order of the Mucorales (previously Zygomyces) and is frequent in patients with decompensated diabetes and severe neutropenia. Aspergillus species constitutes the most frequently isolated mold in the hyaline septated group. However, other invasive hyaline septated molds include Fusarium species, which is frequently resistant to multiple antifungals, and Candida species Last, dematiaceous molds, although infrequent, can be found in neuropathology specimens, as happened during the outbreak of Exserohilum associated with manufacturing practices in a compound pharmacy. CONCLUSIONS: Categorizing hyphae into the three groups described allows pathologists to provide information that is useful for infectious disease treatment with an inclusive differential diagnosis of diverse fungal genera that share the same morphological features.


Subject(s)
Aspergillosis/pathology , Aspergillus fumigatus/isolation & purification , Central Nervous System Fungal Infections/pathology , Hyphae/classification , Mucormycosis/pathology , Saccharomycetales/isolation & purification , Adult , Aged , Aspergillosis/diagnosis , Aspergillosis/microbiology , Central Nervous System Fungal Infections/diagnosis , Central Nervous System Fungal Infections/microbiology , Diagnosis, Differential , Humans , Male , Middle Aged , Mucormycosis/diagnosis , Mucormycosis/microbiology
10.
Pol J Microbiol ; 66(2): 189-199, 2017 Jul 06.
Article in English | MEDLINE | ID: mdl-28735314

ABSTRACT

Pseudomonas putida strain (HM346961) was isolated from a consortium of bacteria acclimatized to unleaded gasoline-contaminated water. The consortium can efficiently remove benzene, toluene, ethylbenzene and xylene (BTEX) isomers, and a similar capability was observed with the P. putida strain. Proteome of this strain showed certain similarities with that of other strains exposed to the hydrocarbon compounds. Furthermore, the toluene di-oxygenase (tod) gene was up-regulated in P. putida strain when exposed to toluene, ethylbenzene, xylene, and BTEX. In contrast, the tod gene of P. putida F1 (ATCC 700007) was up-regulated only in the presence of toluene and BTEX. Several differences in the nucleotide and protein sequences of these two tod genes were observed. This suggests that tod up-regulation in P. putida strain may partially explain their great capacity to remove aromatic compounds, relative to P. putida F1. Therefore, new tod and P. putida strain are promising for various environmental applications.


Subject(s)
Gasoline , Gene Expression Regulation, Bacterial , Microbial Consortia , Pseudomonas putida/metabolism , Adaptation, Physiological , Benzene , Biodegradation, Environmental , Pseudomonas putida/isolation & purification , Toluene , Xylenes
11.
JMM Case Rep ; 4(12): e005134, 2017 Dec.
Article in English | MEDLINE | ID: mdl-29568530

ABSTRACT

INTRODUCTION: Wohlfahrtiimonas chitiniclastica has been associated with open wound infections, cellulitis, osteomyelitis, and bacteremia. CASE PRESENTATION: We report the case of a 41 year old woman with history of congenital myelomeningocele, paraplegia and extensive decubitus ulcers that developed W. chitiniclastica bacteremia secondary to an infected ulcer. CONCLUSION: W. chitiniclastica is an emerging human pathogen that can be readily identified by MALDI-TOF or sequencing.

12.
Food Sci Biotechnol ; 26(4): 1003-1011, 2017.
Article in English | MEDLINE | ID: mdl-30263630

ABSTRACT

Aguamiel is a beverage produced by some Agave species that is consumed in its fresh or fermented form. Despite its uses and popularity, seasonal effects on its microbial and chemical profiles are unknown. In this study, using aguamiel collected from A. salmiana and A. atrovirens during different seasons, we identified microorganisms by sequencing the 16S and 18S rDNA genes and determined their chemical profiles. In total, 49 microbial strains were identified (38 bacteria and 11 yeasts). The highest richness and biodiversity were observed during winter and summer. Different lactic acid bacteria and yeast genera with potential industrial applications were identified, such as Acetobacter, Lactobacillus, Leuconostoc, and Clavispora. The analysis of the chemical profiles indicated the presence of maltooligosaccharides and fructooligosaccharides, which are associated with human health improvements, during spring in Agave aguamiel. Aguamiel can be used in the food industry due to its microbiological and chemical profiles.

13.
Am J Surg Pathol ; 41(2): 271-276, 2017 Feb.
Article in English | MEDLINE | ID: mdl-27819873

ABSTRACT

Hydrophilic polymer coating of medical devices serves to lubricate the device and prevent device-related complications. The coating can be mechanically disrupted and result in downstream injury via presumed thromboembolism. This process has been reported in the brain, heart, lung, and skin, and has been replicated through animal studies and in vitro histologic processing of the polymer coating. We report the first description of hydrophilic polymer-associated ischemic enterocolitis in a series of 7 specimens (small bowel=2, colon=4, aortic thrombus=1) from 3 patients. We report a 4% incidence among all patients with an ischemic bowel resection between April 29, 2014 and August 8, 2016. All patients developed bowel ischemia within 1 day of aortic repair, and all bowel resection specimens showed polymers, mainly in the submucosal vessels in areas of extensive ischemia. The polymers appeared as basophilic, intravascular, serpiginous structures. In a patient who developed acute paralysis after the aortic repair, identical polymers were identified in the aortic thrombus and the ischemic bowel segment. We demonstrate that the polymers display an altered morphology over time and with various graft types, and that the degrading polymers are associated with a foreign body giant cell reaction. Special stains can aid in diagnosis, with the polymers turquoise on a colloidal iron stain, pink on von Kossa and mucicarmine stains, and pale blue on trichrome. Clinical follow-up was available up to 115 weeks: 1 patient died, and 2 are alive and well. In summary, we report a new diagnostic entity to be considered in the differential diagnosis of iatrogenic ischemic injuries in the gastrointestinal tract. Awareness of this entity is important to elucidate the cause of ischemia and to prevent misdiagnosis of the polymers and their associated giant cell reaction as a parasitic infection, granulomatous vasculitis, sarcoidosis, and idiopathic inflammatory bowel disease.


Subject(s)
Colitis, Ischemic/chemically induced , Colitis, Ischemic/pathology , Endovascular Procedures/adverse effects , Polymers/adverse effects , Aged , Endovascular Procedures/instrumentation , Female , Humans , Male , Middle Aged
14.
J Biosci Bioeng ; 119(4): 421-6, 2015 Apr.
Article in English | MEDLINE | ID: mdl-25454696

ABSTRACT

Fructose and fructo-oligosaccharides (FOS) are important ingredients in the food industry. Fructose is considered an alternative sweetener to sucrose because it has higher sweetening capacity and increases iron absorption in children, and FOS's are a source of dietary fiber with a bifidogenic effect. Both compounds can be obtained by enzymatic hydrolysis of inulin. However, inulin presents limited solubility at room temperature, thus, fructose and FOS production is carried out at 60°C. Therefore, there is a growing interest to isolate and characterize thermostable inulinases. The aim of this work was to evaluate the capacity of different fungal strains to produce potential thermostable inulinases. A total of 27 fungal strains belonging to the genera Aspergillus, Penicillium, Rhizopus, Rhizomucor and Thermomyces were evaluated for production of inulinase under submerged culture using Czapek Dox medium with inulin as a sole carbon source. Strains were incubated at 37°C and 200 rpm for 96 h. Crude enzyme extract was obtained to evaluate inulinase and invertase activity. In order to select the fungal strain with the highest thermostable inulinase production, a selection criterion was established. It was possible to determine the highest inulinase activity for Rhizopus microsporus 13aIV (10.71 U/mL) at 36 h with an optimum temperature of inulinase of 70°C. After 6 h at 60°C, the enzyme did not show any significant loss of activity and retained about 87% activity, while it only retains 57% activity at 70°C. According to hydrolysis products, R. microsporus produced endo and exo-inulinase.


Subject(s)
Fungi/genetics , Fungi/metabolism , Glycoside Hydrolases/biosynthesis , Temperature , Enzyme Stability , Fructose/metabolism , Glycoside Hydrolases/genetics , Hydrolysis , Inulin/metabolism
16.
Appl Biochem Biotechnol ; 175(3): 1358-70, 2015 Feb.
Article in English | MEDLINE | ID: mdl-25395059

ABSTRACT

Inulinase is an enzyme produced by plants and several microorganisms, including fungi, to hydrolyze the ß-2,1 glycosidic linkages present in some oligosaccharides to produce fructose and glucose. This enzyme, in conjunction with invertases, levanases, and two types of 1-fructosyl transferases have been described as members of the glycosyl hydrolases (family 32), the most diverse group of enzymes used by microbes for biomass degradation. As being part of the same clan, they have common evolutionary origin sharing the most important functional characteristics. Recently, a xerophylic fungi strain isolated from Mexican semi-desert, Penicillium citrinum ESS has been reported as inulinase producer, which could have greater stability than other enzymes due to a metabolic machinery adapted to typical temperature changes in this region. To continue the understanding of action mechanisms of these enzymes and to establish evolutionary relationships within this family, in the present study, phylogenetic analyses were used to analyze amino acid sequences coding fungal and yeast glycoside hydrolases of family 32, including the new sequenced inulinase of P. citrinum ESS. It was possible to elucidate the action mechanism of fungal glycoside hydrolases in present study and to classify inulinase from P. citrinum ESS as an exo-inulinase on the basis of their amino acid sequence phylogenetic affinities.


Subject(s)
Genes, Fungal , Glycoside Hydrolases/genetics , Glycoside Hydrolases/isolation & purification , Penicillium/enzymology , Penicillium/genetics , Phylogeny , Amino Acid Motifs , Amino Acid Sequence , Base Sequence , Bayes Theorem , Conserved Sequence , Electrophoresis, Agar Gel , Glycoside Hydrolases/chemistry , Molecular Sequence Data , Polymerase Chain Reaction , Sequence Alignment
18.
Ecol Evol ; 3(4): 872-86, 2013 Apr.
Article in English | MEDLINE | ID: mdl-23610632

ABSTRACT

Coral bleaching is a stress response of corals induced by a variety of factors, but these events have become more frequent and intense in response to recent climate-change-related temperature anomalies. We tested the hypothesis that coral reefs affected by bleaching events are currently heavily infested by boring sponges, which are playing a significant role in the destruction of their physical structure. Seventeen reefs that cover the entire distributional range of corals along the Mexican Pacific coast were studied between 2005/2006, and later between 2009/2010. Most of these coral reefs were previously impacted by bleaching events, which resulted in coral mortalities. Sponge abundance and species richness was used as an indicator of bioerosion, and coral cover was used to describe the present condition of coral reefs. Coral reefs are currently highly invaded (46% of the samples examined) by a very high diversity of boring sponges (20 species); being the coral reef framework the substrate most invaded (56%) followed by the rubbles (45%), and the living colonies (36%). The results also indicated that boring sponges are promoting the dislodgment of live colonies and large fragments from the framework. In summary, the eastern coral reefs affected by bleaching phenomena, mainly provoked by El Niño, present a high diversity and abundance of boring sponges, which are weakening the union of the colony with the reef framework and promoting their dislodgment. These phenomena will probably become even more intense and severe, as temperatures are projected to continue to rise under the scenarios for future climate change, which could place many eastern coral reefs beyond their survival threshold.

19.
Int J Oncol ; 41(1): 141-6, 2012 Jul.
Article in English | MEDLINE | ID: mdl-22504553

ABSTRACT

The carcinogenic potential of HPV infections is based on the integration and constitutive expression of the E6 and E7 genes which inhibit the p53 and Rb tumor suppressor proteins. In normal cells, Mdm2 regulates p53 in a negative feedback loop, and although Mdm2 is apparently functional in HPV-infected cells, E6 is the protein responsible for repressing p53 replacing Mdm2 function. The role of Mdm2 in HPV-positive cells is still elusive. In this study, Mdm2 was knocked down in an HPV-positive cervical cancer cell line; as a result we found downregulation of the expression of E6 and E7 and p53 upregulation.


Subject(s)
Gene Expression Regulation, Neoplastic , Human papillomavirus 16/genetics , Oncogene Proteins, Viral/genetics , Papillomavirus E7 Proteins/genetics , Proto-Oncogene Proteins c-mdm2/genetics , Repressor Proteins/genetics , Cell Line, Tumor , Down-Regulation , Female , Gene Knockdown Techniques , Host-Pathogen Interactions , Humans , Oncogene Proteins, Viral/metabolism , Papillomavirus E7 Proteins/metabolism , Papillomavirus Infections/virology , Proto-Oncogene Proteins c-mdm2/metabolism , RNA Interference , Repressor Proteins/metabolism , Tumor Suppressor Protein p53/genetics , Tumor Suppressor Protein p53/metabolism , Uterine Cervical Neoplasms/virology
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