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1.
CA Cancer J Clin ; 72(2): 144-164, 2022 03.
Artículo en Inglés | MEDLINE | ID: mdl-34751943

RESUMEN

The increase in cancer incidence and mortality is challenging current cancer care delivery globally, disproportionally affecting low- and middle-income countries (LMICs) when it comes to receiving evidence-based cancer prevention, treatment, and palliative and survivorship care. Patients in LMICs often rely on traditional, complementary, and integrative medicine (TCIM) that is more familiar, less costly, and widely available. However, spheres of influence and tensions between conventional medicine and TCIM can further disrupt efforts in evidence-based cancer care. Integrative oncology provides a framework to research and integrate safe, effective TCIM alongside conventional cancer treatment and can help bridge health care gaps in delivering evidence-informed, patient-centered care. This growing field uses lifestyle modifications, mind and body therapies (eg, acupuncture, massage, meditation, and yoga), and natural products to improve symptom management and quality of life among patients with cancer. On the basis of this review of the global challenges of cancer control and the current status of integrative oncology, the authors recommend: 1) educating and integrating TCIM providers into the cancer control workforce to promote risk reduction and culturally salient healthy life styles; 2) developing and testing TCIM interventions to address cancer symptoms or treatment-related adverse effects (eg, pain, insomnia, fatigue); and 3) disseminating and implementing evidence-based TCIM interventions as part of comprehensive palliative and survivorship care so patients from all cultures can live with or beyond cancer with respect, dignity, and vitality. With conventional medicine and TCIM united under a cohesive framework, integrative oncology may provide citizens of the world with access to safe, effective, evidence-informed, and culturally sensitive cancer care.


Asunto(s)
Terapias Complementarias , Medicina Integrativa , Oncología Integrativa , Neoplasias , Atención a la Salud , Humanos , Neoplasias/prevención & control , Calidad de Vida
2.
Mol Oncol ; 15(10): 2507-2543, 2021 10.
Artículo en Inglés | MEDLINE | ID: mdl-34515408

RESUMEN

Key stakeholders from the cancer research continuum met in May 2021 at the European Cancer Research Summit in Porto to discuss priorities and specific action points required for the successful implementation of the European Cancer Mission and Europe's Beating Cancer Plan (EBCP). Speakers presented a unified view about the need to establish high-quality, networked infrastructures to decrease cancer incidence, increase the cure rate, improve patient's survival and quality of life, and deal with research and care inequalities across the European Union (EU). These infrastructures, featuring Comprehensive Cancer Centres (CCCs) as key components, will integrate care, prevention and research across the entire cancer continuum to support the development of personalized/precision cancer medicine in Europe. The three pillars of the recommended European infrastructures - namely translational research, clinical/prevention trials and outcomes research - were pondered at length. Speakers addressing the future needs of translational research focused on the prospects of multiomics assisted preclinical research, progress in Molecular and Digital Pathology, immunotherapy, liquid biopsy and science data. The clinical/prevention trial session presented the requirements for next-generation, multicentric trials entailing unified strategies for patient stratification, imaging, and biospecimen acquisition and storage. The third session highlighted the need for establishing outcomes research infrastructures to cover primary prevention, early detection, clinical effectiveness of innovations, health-related quality-of-life assessment, survivorship research and health economics. An important outcome of the Summit was the presentation of the Porto Declaration, which called for a collective and committed action throughout Europe to develop the cancer research infrastructures indispensable for fostering innovation and decreasing inequalities within and between member states. Moreover, the Summit guidelines will assist decision making in the context of a unique EU-wide cancer initiative that, if expertly implemented, will decrease the cancer death toll and improve the quality of life of those confronted with cancer, and this is carried out at an affordable cost.


Asunto(s)
Neoplasias , Calidad de Vida , Europa (Continente)/epidemiología , Humanos , Neoplasias/epidemiología , Neoplasias/prevención & control , Medicina de Precisión , Investigación Biomédica Traslacional
3.
Prev Med ; 151: 106624, 2021 10.
Artículo en Inglés | MEDLINE | ID: mdl-34023359

RESUMEN

Cancer screening programs from majority of the low- and middle-income countries (LMICs) report screening coverage as the only performance indicator, and that too measured through population-based sample surveys. Such information is unreliable and has very little value in assessing programmatic quality and impact. Regular monitoring of key process and outcome indicators based on data collected through a robust information system is essential to ensure quality of a screening programme. Fragmented health systems, limited resources and absence of a culture of systematic evaluation are the major hindrances for most of the LMICs to build electronic information systems to manage screening. The COVID-19 pandemic has created an impetus for the countries to customize the freely available District Health Information Software (DHIS2) to collect electronic data to track the outbreaks and manage containment measures. In the present article we present Bangladesh as an exemplar LMIC that has a (DHIS2) based integrated health information system gradually upgraded to collect individual data of the participants to the national cervical cancer screening program. Such efforts paid rich dividends as the screening program was switched from opportunistic to a population-based one. Moreover, the electronic system could report impact of the pandemic on cancer screening on a monthly basis. The aggregate number of women screened in the year 2020 was 14.1% less compared to 2019. The monthly rate of screening during peak of the outbreak was only 5.1% of the previous year. The rate rapidly recovered as the program intensified screening in the hard-to-reach regions less affected by the pandemic and expanded the outreach services. Other LMICs may emulate Bangladesh example. Customizing the information system developed for pandemic surveillance to collect cancer screening data will help them build back the screening programs better.


Asunto(s)
COVID-19 , Neoplasias del Cuello Uterino , Bangladesh/epidemiología , Países en Desarrollo , Detección Precoz del Cáncer , Femenino , Humanos , Pandemias , SARS-CoV-2 , Neoplasias del Cuello Uterino/diagnóstico
4.
Metallomics ; 13(6)2021 05 31.
Artículo en Inglés | MEDLINE | ID: mdl-33930157

RESUMEN

Selenium is an essential trace element whose compounds are widely metabolized by organisms from all three domains of life. Moreover, phylogenetic evidence indicates that selenium species, along with iron, molybdenum, tungsten, and nickel, were metabolized by the last universal common ancestor of all cellular lineages, primarily for the synthesis of the 21st amino acid selenocysteine. Thus, selenium metabolism is both environmentally ubiquitous and a physiological adaptation of primordial life. Selenium metabolic reactions comprise reductive transformations both for assimilation into macromolecules and dissimilatory reduction of selenium oxyanions and elemental selenium during anaerobic respiration. This review offers a comprehensive overview of the physiology and evolution of both assimilatory and dissimilatory selenium metabolism in bacteria and archaea, highlighting mechanisms of selenium respiration. This includes a thorough discussion of our current knowledge of the physiology of selenocysteine synthesis and incorporation into proteins in bacteria obtained from structural biology. Additionally, this is the first comprehensive discussion in a review of the incorporation of selenium into the tRNA nucleoside 5-methylaminomethyl-2-selenouridine and as an inorganic cofactor in certain molybdenum hydroxylase enzymes. Throughout, conserved mechanisms and derived features of selenium metabolism in both domains are emphasized and discussed within the context of the global selenium biogeochemical cycle.


Asunto(s)
Archaea/metabolismo , Bacterias/metabolismo , Evolución Molecular , Molibdeno/metabolismo , Selenio/metabolismo , Oxigenasas de Función Mixta/metabolismo , ARN de Transferencia/química , ARN de Transferencia/metabolismo , Selenocisteína/química , Selenocisteína/metabolismo
5.
Cancer Causes Control ; 32(5): 429-440, 2021 May.
Artículo en Inglés | MEDLINE | ID: mdl-33528692

RESUMEN

Breast cancer is the most frequently diagnosed cancer among women in both transitioned and transitioning countries and has become a major women's health problem. Although recent advances in our understanding of the biological nature of cancer, improved awareness coupled with better early detection facilities, use of chemotherapy, hormone therapy, and targeted therapy have significantly improved survival from cancer, there are many gaps in providing individual-centric, holistic care. Integrative medicine refers to the use of traditional medicine alongside conventional preventive or therapeutic interventions (allopathic medicine) as a comprehensive, individual-centered, evidence-based care. The three pillars of complementary medicine (lifestyle modifications, mind-body practices, and use of natural products) have the potential for cancer prevention and improving quality-of-life and even treatment response in cancer patients when combined with conventional oncology care. Therefore, continued research into integrative therapies is required to extend the benefits to a broader patient population and improve outcomes in breast and other common cancers. In the present review article, the possible role of integrative medicine across the breast cancer care continuum has been discussed along with the concept of integrating complementary practices into mainstream health delivery. We have focused on breast cancer as a model cancer that is well amenable to prevention, early detection and stage appropriate treatment. However, our observations are pertinent for other common cancers, for which there are several opportunities for improving the continuum of care, especially in developing countries like India.


Asunto(s)
Neoplasias de la Mama/terapia , Terapias Complementarias/métodos , Medicina Integrativa/métodos , Continuidad de la Atención al Paciente , Atención a la Salud/organización & administración , Femenino , Humanos , India , Calidad de Vida
6.
Sci Rep ; 10(1): 10946, 2020 07 02.
Artículo en Inglés | MEDLINE | ID: mdl-32616801

RESUMEN

Mononuclear molybdoenzymes of the dimethyl sulfoxide reductase (DMSOR) family catalyze a number of reactions essential to the carbon, nitrogen, sulfur, arsenic, and selenium biogeochemical cycles. These enzymes are also ancient, with many lineages likely predating the divergence of the last universal common ancestor into the Bacteria and Archaea domains. We have constructed rooted phylogenies for over 1,550 representatives of the DMSOR family using maximum likelihood methods to investigate the evolution of the arsenic biogeochemical cycle. The phylogenetic analysis provides compelling evidence that formylmethanofuran dehydrogenase B subunits, which catalyze the reduction of CO2 to formate during hydrogenotrophic methanogenesis, constitutes the most ancient lineage. Our analysis also provides robust support for selenocysteine as the ancestral ligand for the Mo/W atom. Finally, we demonstrate that anaerobic arsenite oxidase and respiratory arsenate reductase catalytic subunits represent a more ancient lineage of DMSORs compared to aerobic arsenite oxidase catalytic subunits, which evolved from the assimilatory nitrate reductase lineage. This provides substantial support for an active arsenic biogeochemical cycle on the anoxic Archean Earth. Our work emphasizes that the use of chalcophilic elements as substrates as well as the Mo/W ligand in DMSORs has indelibly shaped the diversification of these enzymes through deep time.


Asunto(s)
Archaea/enzimología , Proteínas Arqueales/metabolismo , Arsénico/metabolismo , Bacterias/enzimología , Proteínas Bacterianas/metabolismo , Proteínas Hierro-Azufre/metabolismo , Metano/metabolismo , Oxidorreductasas/metabolismo , Selenio/metabolismo , Evolución Molecular , Filogenia
7.
Asian Pac J Cancer Prev ; 21(5): 1391-1398, 2020 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-32458647

RESUMEN

BACKGROUND: The prospective randomized study aimed to compare the safety, acceptability and efficacy of thermal ablation (TA) to that of cryotherapy in screen and treat setting. METHODS: The participants were recruited prospectively in a community-based screening clinic in India. Women positive on visual inspection with acetic acid (VIA) test and/or Human Papillomavirus (HPV) test were assessed for eligibility for ablative treatment. Total 286 eligible women were randomized to receive either cryotherapy (N=150) or TA (N=136) performed by health workers. Colposcopy and cervical biopsy were performed on all, prior to treatment. Post-treatment follow-up was after one year with colposcopy and biopsy. RESULTS: Both the treatment methods had high acceptability. Significantly higher proportion of women treated by cryotherapy reported pain compared to women treated by TA, though intensity was mild in vast majority of them. Approximately 30% of women in both arms had histologic abnormalities, mainly CIN 1, and among those who attended follow-up 74.1% and 81.0% didn't have any CIN after cryotherapy and TA respectively. CONCLUSION: TA is as acceptable and safe as cryotherapy in screen and treat setting. TA has the logistic advantages for the low-resourced settings as the machines are more portable, do not require costly refrigerant gas and battery-driven models are available. The cure rates for CIN 1+ lesions in our study were comparable between cryotherapy and TA.


Asunto(s)
Técnicas de Ablación/métodos , Crioterapia/métodos , Detección Precoz del Cáncer/métodos , Hipertermia Inducida/métodos , Infecciones por Papillomavirus/complicaciones , Displasia del Cuello del Útero/terapia , Neoplasias del Cuello Uterino/terapia , Adulto , Femenino , Estudios de Seguimiento , Humanos , Persona de Mediana Edad , Papillomaviridae/aislamiento & purificación , Seguridad del Paciente , Pronóstico , Estudios Prospectivos , Neoplasias del Cuello Uterino/diagnóstico , Neoplasias del Cuello Uterino/patología , Neoplasias del Cuello Uterino/virología , Displasia del Cuello del Útero/diagnóstico , Displasia del Cuello del Útero/patología , Displasia del Cuello del Útero/virología
8.
Lancet Oncol ; 21(1): 175-184, 2020 01.
Artículo en Inglés | MEDLINE | ID: mdl-31734069

RESUMEN

BACKGROUND: Cryotherapy is standard practice for treating patients with cervical precancer in see-and-treat programmes in low-income and middle-income countries (LMICs). Because of logistical difficulties with cryotherapy (eg, the necessity, costs, and supply chain difficulties of refrigerant gas; equipment failure; and treatment duration >10 min), a battery-operated thermal ablator that is lightweight and portable has been developed. We aimed to compare thermal ablation using the new device with cryotherapy. METHODS: We report the pilot phase of a randomised controlled trial in routine screen-and-treat clinics providing cervical screening using visual inspection with acetic acid (VIA) in Lusaka, Zambia. We recruited non-pregnant women, aged 25 years or older, who were eligible for ablative therapy. We randomly assigned participants (1:1:1) to thermal ablation, cryotherapy, or large loop excision of the transformation zone (LLETZ), using computer-generated allocation. The randomisation was concealed but the nurses providing treatment and the participants were unmasked. Thermal ablation was achieved using the Liger thermal ablator (using 1-5 overlapping applications of the probe heated to 100°C, each application lasting for 40 s), cryotherapy was carried out using the double-freeze technique (freeze for 3 min, thaw for 5 min, and freeze again for 3 min), and LLETZ (using a large loop driven by an electro-surgical unit to excise the transformation zone) was done under local anaesthesia. The primary endpoint was treatment success, defined as either human papillomavirus (HPV) type-specific clearance among participants who were positive for the same HPV type at baseline, or a negative VIA test at 6-month follow-up, if the baseline HPV test was negative. Per protocol analyses were done. Enrolment for the full trial is ongoing. Here, we present findings from a prespecified pilot phase of the full trial. The final analysis of the full trial will assess non-inferiority of the groups for the primary efficacy endpoint. The study is registered with ClinicalTrials.gov, number NCT02956239. FINDINGS: Between Aug 2, 2017, and Jan 15, 2019, 750 participants were randomly assigned (250 per group). 206 (84%) participants in the cryotherapy group, 197 (81%) in the thermal ablation group, and 204 (84%) in the LLETZ group attended the 6-month follow-up examination. Treatment success was reported in 120 (60%) of 200 participants in the cryotherapy group, 123 (64%) of 192 in the thermal ablation group, and 134 (67%) of 199 in the LLETZ group (p=0·31). Few participants complained of moderate to severe pain in any group immediately after the procedure (six [2%] of 250 in the cryotherapy group, four [2%] of 250 in the thermal ablation group, and five [2%] of 250 in the LLETZ group) and 2 weeks after the procedure (one [<1%] of 241 in the cryotherapy group, none of 242 in the thermal ablation group, and two [<1%] of 237 in the LLETZ group). None of the participants reported any complication requiring medical consultation or admission to hospital. INTERPRETATION: Results from this pilot study preliminarily suggest that thermal ablation has similar treatment success to cryotherapy, without the practical disadvantages of providing cryotherapy in an LMIC. However, the study was not powered to establish the similarity between the techniques, and results from the ongoing randomised controlled trial are need to confirm these results. FUNDING: US National Institutes of Health.


Asunto(s)
Ácido Acético/química , Crioterapia/métodos , Electrocirugia/métodos , Hipertermia Inducida/métodos , Infecciones por Papillomavirus/complicaciones , Displasia del Cuello del Útero/terapia , Neoplasias del Cuello Uterino/terapia , Adulto , Detección Precoz del Cáncer/métodos , Femenino , Estudios de Seguimiento , Humanos , Persona de Mediana Edad , Papillomaviridae/aislamiento & purificación , Infecciones por Papillomavirus/virología , Proyectos Piloto , Pronóstico , Estudios Prospectivos , Neoplasias del Cuello Uterino/patología , Neoplasias del Cuello Uterino/virología , Displasia del Cuello del Útero/patología , Displasia del Cuello del Útero/virología
9.
J Biol Chem ; 289(15): 10345-10358, 2014 Apr 11.
Artículo en Inglés | MEDLINE | ID: mdl-24500710

RESUMEN

Mitochondrial amidoxime reducing component (mARC) proteins are molybdopterin-containing enzymes of unclear physiological function. Both human isoforms mARC-1 and mARC-2 are able to catalyze the reduction of nitrite when they are in the reduced form. Moreover, our results indicate that mARC can generate nitric oxide (NO) from nitrite when forming an electron transfer chain with NADH, cytochrome b5, and NADH-dependent cytochrome b5 reductase. The rate of NO formation increases almost 3-fold when pH was lowered from 7.5 to 6.5. To determine if nitrite reduction is catalyzed by molybdenum in the active site of mARC-1, we mutated the putative active site cysteine residue (Cys-273), known to coordinate molybdenum binding. NO formation was abolished by the C273A mutation in mARC-1. Supplementation of transformed Escherichia coli with tungsten facilitated the replacement of molybdenum in recombinant mARC-1 and abolished NO formation. Therefore, we conclude that human mARC-1 and mARC-2 are capable of catalyzing reduction of nitrite to NO through reaction with its molybdenum cofactor. Finally, expression of mARC-1 in HEK cells using a lentivirus vector was used to confirm cellular nitrite reduction to NO. A comparison of NO formation profiles between mARC and xanthine oxidase reveals similar Kcat and Vmax values but more sustained NO formation from mARC, possibly because it is not vulnerable to autoinhibition via molybdenum desulfuration. The reduction of nitrite by mARC in the mitochondria may represent a new signaling pathway for NADH-dependent hypoxic NO production.


Asunto(s)
Coenzimas/metabolismo , Metaloproteínas/metabolismo , Mitocondrias/enzimología , Proteínas Mitocondriales/metabolismo , Óxido Nítrico Sintasa/metabolismo , Nitrito Reductasas/metabolismo , Oxidorreductasas/metabolismo , Pteridinas/metabolismo , Secuencia de Aminoácidos , Reductasas del Citocromo/metabolismo , Citocromos b5/metabolismo , Transporte de Electrón , Células HEK293 , Humanos , Concentración de Iones de Hidrógeno , Cinética , Datos de Secuencia Molecular , Molibdeno/metabolismo , Cofactores de Molibdeno , Óxido Nítrico/metabolismo , Nitritos/metabolismo , Oxígeno/metabolismo , Proteínas Recombinantes/metabolismo , Homología de Secuencia de Aminoácido , Xantina Oxidasa/metabolismo
10.
Asian Pac J Cancer Prev ; 14(10): 5753-9, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-24289574

RESUMEN

Curcumin and curcumin containing polyherbal preparations have demonstrated anti-microbial and anti- viral properties in pre-clinical studies. Till date no therapeutic intervention has been proved to be effective and safe in clearing established cervical human papillomavirus (HPV) infection. The present study evaluated the efficacy of Basant polyherbal vaginal cream (containing extracts of curcumin, reetha, amla and aloe vera) and of curcumin vaginal capsules to eliminate HPV infection from cervix. Women were screened by Pap smear and HPV DNA test by PCR. HPV positive women without high grade cervical neoplasias (N=287) were randomized to four intervention arms to be treated with vaginal Basant cream, vaginal placebo cream, curcumin vaginal capsules and placebo vaginal capsules respectively. All subjects were instructed to use one application of the assigned formulation daily for 30 consecutive days except during menstruation and recalled within seven days of the last application for repeat HPV test, cytology and colposcopy. HPV clearance rate in Basant arm (87.7%) was significantly higher than the combined placebo arms (73.3%). Curcumin caused higher rate of clearance (81.3%) than placebo though the difference was not statistically significant. Vaginal irritation and itching, mostly mild to moderate, was significantly higher after Basant application. No serious adverse events were noted.


Asunto(s)
Curcumina/uso terapéutico , Papillomaviridae/efectos de los fármacos , Infecciones por Papillomavirus/tratamiento farmacológico , Extractos Vegetales/uso terapéutico , Cremas, Espumas y Geles Vaginales/uso terapéutico , Adulto , Cuello del Útero/efectos de los fármacos , Cuello del Útero/virología , Femenino , Humanos , Prueba de Papanicolaou/métodos , Infecciones por Papillomavirus/virología , Plantas Medicinales , Frotis Vaginal/métodos
11.
Annu Rev Microbiol ; 60: 107-30, 2006.
Artículo en Inglés | MEDLINE | ID: mdl-16704340

RESUMEN

Arsenic and selenium are readily metabolized by prokaryotes, participating in a full range of metabolic functions including assimilation, methylation, detoxification, and anaerobic respiration. Arsenic speciation and mobility is affected by microbes through oxidation/reduction reactions as part of resistance and respiratory processes. A robust arsenic cycle has been demonstrated in diverse environments. Respiratory arsenate reductases, arsenic methyltransferases, and new components in arsenic resistance have been recently described. The requirement for selenium stems primarily from its incorporation into selenocysteine and its function in selenoenzymes. Selenium oxyanions can serve as an electron acceptor in anaerobic respiration, forming distinct nanoparticles of elemental selenium that may be enriched in (76)Se. The biogenesis of selenoproteins has been elucidated, and selenium methyltransferases and a respiratory selenate reductase have also been described. This review highlights recent advances in ecology, biochemistry, and molecular biology and provides a prelude to the impact of genomics studies.


Asunto(s)
Arsénico/metabolismo , Bacterias/metabolismo , Selenio/metabolismo , Secuencia de Aminoácidos , Arseniato Reductasas/fisiología , Resistencia a Medicamentos , Ecología , Metilación , Datos de Secuencia Molecular , Oxidorreductasas/fisiología , Filogenia , Selenocisteína/metabolismo
12.
Int. microbiol ; 5(4): 201-207, dic. 2002.
Artículo en Inglés | IBECS | ID: ibc-30461

RESUMEN

Microbial activity is responsible for the transformation of at least one third of the elements in the periodic table. These transformations are the result of assimilatory, dissimilatory, or detoxification processes and form the cornerstones of many biogeochemical cycles. Arsenic and selenium are two elements whose roles in microbial ecology have only recently been recognized. Known as «essential toxins», they are required in trace amounts for growth and metabolism but are toxic at elevated concentrations. Arsenic is used as an osmolite in some marine organisms while selenium is required as selenocysteine (i.e. the twenty-first amino acid) or as a ligand to metal in some enzymes (e.g. FeNiSe hydrogenase). Arsenic resistance involves a small-molecular-weight arsenate reductase (ArsC). The use of arsenic and selenium oxyanions for energy is widespread in prokaryotes with representative organisms from the Crenarchaeota, thermophilic bacteria, low and high G+C gram-positive bacteria, and Proteobacteria. Recent studies have shown that both elements are actively cycled and play a significant role in carbon mineralization in certain environments. The occurrence of multiple mechanisms involving different enzymes for arsenic and selenium transformation indicates several different evolutionary pathways (e.g. convergence and lateral gene transfer) and underscores the environmental significance and selective impact in microbial evolution of these two elements (AU)


La actividad microbiana es responsable de la transformación de al menos un tercio de los elementos de la tabla periódica. Estas transformaciones son resultado de procesos de asimilación, desasimilación o destoxificación, y son la piedra angular de de muchos ciclos biogeoquímicos. El arsénico y el selenio son dos elementos cuyo papel en la ecología microbiana ha sido reconocido sólo recientemente. Conocidos como «toxinas esenciales», son necesarios en concentraciones mínimas para el crecimiento y el metabolismo, pero son tóxicos a concentraciones elevadas. Algunos animales marinos utilizan el arsénico como osmólito, mientras que el selenio es necesario para formar la selenocisteína (el aminoácido 21) o como ligando de los metales en algunas enzimas (ej. FeNiSe hidrogenasa). En la resistencia al arsénico interviene una arsenato reductasa de bajo peso molecular (ArsC). El uso de oxianiones de arsénico y de selenio para la obtención de energía está muy difundido en los organismos procariotas, con representantes en el grupo Crenarchaeota, en las bacterias termófilas, las bacterias grampositivas de bajo y alto porcentaje de G+C, y entre las proteobacterias. Estudios recientes muestran que los dos elementos siguen un ciclo activo y desempeñan un papel importante en la mineralización del carbono en ciertos ambientes. La presencia de muchos mecanismos en los que intervienen diversas enzimas para la transformación del selenio y del arsénico indica que ha habido distintas rutas evolutivas (por ejemplo, convergencia, y transferencia horizontal de genes) y marca el significado ambiental de estos dos elementos y su impacto selectivo en la evolución microbiana. (AU)


Asunto(s)
Selenio , Complejos Multienzimáticos , Arsénico/metabolismo , Bacterias/metabolismo , Bombas Iónicas/metabolismo , Filogenia , Oxidorreductasas/metabolismo , Biotransformación , Adenosina Trifosfatasas/metabolismo
13.
Asian Pac J Cancer Prev ; 2(4): 305-308, 2001.
Artículo en Inglés | MEDLINE | ID: mdl-12718623

RESUMEN

Carcinoma of the uterine cervix is preceded by well characterized pre-cancerous lesions which if left untreated may progress to invasive carcinoma. In the present study women in the age group of 35-55 years with cervical intraepithelial lesions (CIN I & II) were treated with vitamin E and advised to come for follow up after every three months for one year. This preliminary report shows vitamin E can restrict and regress CIN I & II lesions with elevation in circulating vitamin E levels. Improvement in immune status as reflected in mitogenic responses of peripheral blood lymphocytes was also noted.

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