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1.
Rev. esp. cir. ortop. traumatol. (Ed. impr.) ; 67(6): 487-499, Nov-Dic. 2023. tab, ilus
Artigo em Inglês | IBECS | ID: ibc-227615

RESUMO

Los paradigmas de tratamiento para pacientes con metástasis de columna vertebral han evolucionado significativamente en las últimas dos décadas. El cambio más transformador de estos paradigmas ha sido la integración de la radiocirugía estereotáctica espinal (sSRS). La sSRS permite la administración de dosis de radiación lítica con preservación de los órganos cercanos en riesgo, particularmente la médula espinal. La evidencia apoya la seguridad y la eficacia de la radiocirugía, ya que actualmente ofrece un control tumoral local duradero con bajas tasas de complicaciones, incluso para tumores que anteriormente se consideraban radiorresistentes a la radioterapia convencional de haz externo. El papel de la intervención quirúrgica sigue siendo consistente, pero se ha observado una tendencia hacia técnicas menos agresivas, a menudo mínimamente invasivas. Utilizando tecnologías modernas e instrumentación mejorada, los resultados quirúrgicos continúan mejorando con una morbilidad reducida. Además, los agentes dirigidos, como los productos biológicos y los inhibidores de puntos de control, han revolucionado la atención del cáncer al mejorar tanto el control local como la supervivencia del paciente. Estos avances han dado lugar a la necesidad de nuevas herramientas de pronóstico y a una revisión más crítica de los resultados a largo plazo. La naturaleza compleja de los esquemas de tratamiento actuales requiere un enfoque multidisciplinario que incluya cirujanos, oncólogos médicos, oncólogos radioterápicos, intervencionistas y especialistas en dolor. Esta revisión recapitula los datos actuales basados en la evidencia sobre el tratamiento de las metástasis espinales e integra estos datos en un marco de decisión, NOMS, que se basa en cuatro pilares centinela de la toma de decisiones en tumores metastásicos de la columna vertebral: estado neurológico, comportamiento oncológico del tumor, estabilidad mecánica, y carga sistémica de la enfermedad y comorbilidades médicas.(AU)


Spinal metastases are a common oncologic challenge as 20–40% of cancer patients are affected during the course of their illness and up to 20% of those will become symptomatic from spinal cord compression.1–5 The magnitude of this problem is expected to grow commensurate with the exponential rise in the use of targeted therapies which have demonstrated markedly improved survivals for virtually all malignant tumors. Additionally, the increased availability of advanced diagnostic imaging such as magnetic resonance imaging and 18-FDG PET scans will also serve to increase detection of spine metastatic disease. Despite extended survivals conveyed by biologics and checkpoint inhibitors, the treatment goals for patients with spine metastases remain palliative and focused on the preservation or restoration of neurological function and spinal stability, improved pain control and health related quality of life (HRQOL), and durable tumor control. Scoring systems such as the Tomita score6 and Tokuhashi revised score7 historically have been used to estimate survival and dictate treatment but increasingly have become obsolete due to their inability to incorporate and account for advances in all domains of cancer treatment.(AU)


Assuntos
Humanos , Medula Espinal , Neoplasias da Medula Espinal/tratamento farmacológico , Metástase Neoplásica/terapia , Radiocirurgia , Neoplasias/tratamento farmacológico , Traumatologia , Procedimentos Ortopédicos , Ortopedia
2.
Rev. esp. cir. ortop. traumatol. (Ed. impr.) ; 67(6): S487-S499, Nov-Dic. 2023. tab, ilus
Artigo em Espanhol | IBECS | ID: ibc-227616

RESUMO

Los paradigmas de tratamiento para pacientes con metástasis de columna vertebral han evolucionado significativamente en las últimas dos décadas. El cambio más transformador de estos paradigmas ha sido la integración de la radiocirugía estereotáctica espinal (sSRS). La sSRS permite la administración de dosis de radiación lítica con preservación de los órganos cercanos en riesgo, particularmente la médula espinal. La evidencia apoya la seguridad y la eficacia de la radiocirugía, ya que actualmente ofrece un control tumoral local duradero con bajas tasas de complicaciones, incluso para tumores que anteriormente se consideraban radiorresistentes a la radioterapia convencional de haz externo. El papel de la intervención quirúrgica sigue siendo consistente, pero se ha observado una tendencia hacia técnicas menos agresivas, a menudo mínimamente invasivas. Utilizando tecnologías modernas e instrumentación mejorada, los resultados quirúrgicos continúan mejorando con una morbilidad reducida. Además, los agentes dirigidos, como los productos biológicos y los inhibidores de puntos de control, han revolucionado la atención del cáncer al mejorar tanto el control local como la supervivencia del paciente. Estos avances han dado lugar a la necesidad de nuevas herramientas de pronóstico y a una revisión más crítica de los resultados a largo plazo. La naturaleza compleja de los esquemas de tratamiento actuales requiere un enfoque multidisciplinario que incluya cirujanos, oncólogos médicos, oncólogos radioterápicos, intervencionistas y especialistas en dolor. Esta revisión recapitula los datos actuales basados en la evidencia sobre el tratamiento de las metástasis espinales e integra estos datos en un marco de decisión, NOMS, que se basa en cuatro pilares centinela de la toma de decisiones en tumores metastásicos de la columna vertebral: estado neurológico, comportamiento oncológico del tumor, estabilidad mecánica, y carga sistémica de la enfermedad y comorbilidades médicas.(AU)


Spinal metastases are a common oncologic challenge as 20–40% of cancer patients are affected during the course of their illness and up to 20% of those will become symptomatic from spinal cord compression.1–5 The magnitude of this problem is expected to grow commensurate with the exponential rise in the use of targeted therapies which have demonstrated markedly improved survivals for virtually all malignant tumors. Additionally, the increased availability of advanced diagnostic imaging such as magnetic resonance imaging and 18-FDG PET scans will also serve to increase detection of spine metastatic disease. Despite extended survivals conveyed by biologics and checkpoint inhibitors, the treatment goals for patients with spine metastases remain palliative and focused on the preservation or restoration of neurological function and spinal stability, improved pain control and health related quality of life (HRQOL), and durable tumor control. Scoring systems such as the Tomita score6 and Tokuhashi revised score7 historically have been used to estimate survival and dictate treatment but increasingly have become obsolete due to their inability to incorporate and account for advances in all domains of cancer treatment.(AU)


Assuntos
Humanos , Masculino , Feminino , Medula Espinal , Neoplasias da Medula Espinal/tratamento farmacológico , Metástase Neoplásica/terapia , Radiocirurgia , Neoplasias/tratamento farmacológico , Traumatologia , Procedimentos Ortopédicos , Ortopedia
3.
Rev Esp Cir Ortop Traumatol ; 67(6): S487-S499, 2023.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-37562765

RESUMO

Treatment paradigms for patients with spine metastases have evolved significantly over the past two decades. The most transformative change to these paradigms has been the integration of spinal stereotactic radiosurgery (sSRS). sSRS allows for the delivery of tumoricidal radiation doses with sparing of nearby organs at risk, particularly the spinal cord. Evidence supports the safety and efficacy of radiosurgery as it currently offers durable local tumor control with low complication rates even for tumors previously considered radioresistant to conventional external beam radiation therapy. The role for surgical intervention remains consistent, but a trend has been observed toward less aggressive, often minimally invasive techniques. Using modern technologies and improved instrumentation, surgical outcomes continue to improve with reduced morbidity. Additionally, targeted agents such as biologics and checkpoint inhibitors have revolutionized cancer care by improving both local control and patient survival. These advances have brought forth a need for new prognostication tools and a more critical review of long-term outcomes. The complex nature of current treatment schemes necessitates a multidisciplinary approach including surgeons, medical oncologists, radiation oncologists, interventionalists and pain specialists. This review recapitulates the current state-of-the-art, evidence-based data on the treatment of spinal metastases and integrates these data into a decision framework, NOMS, which is based on four sentinel pillars of decision making in metastatic spine tumors: neurological status, Oocologic tumor behavior, mechanical stability and systemic disease burden and medical co-morbidities.

4.
Rev Esp Cir Ortop Traumatol ; 67(6): 487-499, 2023.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-37116749

RESUMO

Treatment paradigms for patients with spine metastases have evolved significantly over the past two decades. The most transformative change to these paradigms has been the integration of spinal stereotactic radiosurgery (sSRS). sSRS allows for the delivery of tumoricidal radiation doses with sparing of nearby organs at risk, particularly the spinal cord. Evidence supports the safety and efficacy of radiosurgery as it currently offers durable local tumor control with low complication rates even for tumors previously considered radioresistant to conventional external beam radiation therapy. The role for surgical intervention remains consistent, but a trend has been observed toward less aggressive, often minimally invasive techniques. Using modern technologies and improved instrumentation, surgical outcomes continue to improve with reduced morbidity. Additionally, targeted agents such as biologics and checkpoint inhibitors have revolutionized cancer care by improving both local control and patient survival. These advances have brought forth a need for new prognostication tools and a more critical review of long-term outcomes. The complex nature of current treatment schemes necessitates a multidisciplinary approach including surgeons, medical oncologists, radiation oncologists, interventionalists and pain specialists. This review recapitulates the current state-of-the-art, evidence-based data on the treatment of spinal metastases and integrates these data into a decision framework, NOMS, which is based on four sentinel pillars of decision making in metastatic spine tumors: Neurological status, Oncologic tumor behavior, Mechanical stability, and Systemic disease burden and medical co-morbidities.

5.
J Am Chem Soc ; 123(50): 12590-5, 2001 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-11741423

RESUMO

Oxidation potentials, E1/2(ox) of alpha-hydroxyalkyl radicals of the type R(1)R(2)C(*)OH (denoted K(1)H(*)) have been obtained in acetonitrile by photomodulated voltammetry. The values of E1/2(ox) increase as the R(1) and R(2) groups are changed from alkyl to aryl and, in particular, strong electron-withdrawing functionalities such as CN and CF3. Using rate data available in the literature for the pinacol photoexchange reaction K + K(1)H(*) --> KH(*) + K(1), it is found that as the difference in the standard potential of the ketone K, EK degrees and the oxidation potential of K(1)H(*), E1/2(ox), increases there is a modest increase in the exchange rate constant, k(ex). This indicates that even if some charge transfer may occur between the hydroxyalkyl radical and the ketone in the transition state, it is certainly not to the extent of a complete electron transfer. If the exchange reaction is treated as a simple hydrogen atom transfer process within the Marcus model, the intrinsic barrier is found to be 8-13 kcal mol(-1) due to the changes occurring in bonds, hybridizations, and bond angles. Finally, acid dissociation constants for K(1)H(*) are provided by means of a thermochemical cycle.

6.
J Appl Microbiol ; 83(1): 111-9, 1997 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-9246777

RESUMO

Food-related Penicillium species (n = 34) and Geotrichum candidum (n = 11) grown on Czapek Dox and brie agar were tested for their ability to suppress growth of pathogenic bacteria. Ten out of 13 P. camemberti showed antagonistic activity while the other species did not interact significantly with the bacterial growth. The order of inhibition was: Gram-negative bacteria and Bacillus cereus > Listeria monocytogenes, Lactococcus sp. > Micrococcus sp. whereas Lactobacillus sp., Staphylococcus aureus and some Micrococcus sp. were unaffected. When Salmonella typhimurium was inoculated together with P. camemberti P25 in brie agar, bacterial growth was inhibited during the first 6 d of incubation whereafter growth started. The inhibition of L. monocytogenes was similar but less pronounced. The antimicrobial activity produced by P. camemberti P25 and L84 was enhanced with increasing amount of sucrose in the medium. The activity was increased at low pH and destroyed at pH above 8. It was detectable at 15 degrees C but not at 37 degrees C indicating that volatile metabolites might be involved. No significant accumulation of organic acids and no secondary metabolites such as mycotoxins were detected. HSGC-MS analysis indicated that acetaldehyde, benzaldehyde, 3-methylbutanal and 1-octen-3-ol were produced by P. camemberti during the period when inhibitory activity was observed. Pure acetaldehyde and benzaldehyde were shown to be inhibitory to L. monocytogenes and Salm. typhimurium when grown at 15 degrees C and pH 5.5 and 7.0.


Assuntos
Antibacterianos/metabolismo , Queijo/microbiologia , Bactérias Gram-Negativas/crescimento & desenvolvimento , Penicillium/fisiologia , Acetaldeído/metabolismo , Técnicas Bacteriológicas , Benzaldeídos/metabolismo , Meios de Cultura , Bactérias Gram-Negativas/metabolismo , Concentração de Íons de Hidrogênio , Penicillium/química , Temperatura
7.
J Gen Microbiol ; 139(9): 1973-8, 1993 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-8245827

RESUMO

A Lactobacillus plantarum bacteriocin, plantaricin A, has been purified to homogeneity by ammonium sulphate precipitation, binding to cation exchanger and Octyl-Sepharose, and reverse-phase chromatography. The bacteriocin activity was associated with two peptides, termed alpha and beta, which were separated upon reverse-phase chromatography. Bacteriocin activity required the complementary action of both the alpha and beta peptides. From the N-terminal end, 21 and 22 amino acid residues of alpha and beta, respectively, were sequenced. Further attempts at sequencing revealed no additional amino acid residues, suggesting that either the C terminus had been reached or that modifications in the next amino acid residue blocked the sequencing reaction. Judging from their amino acid sequence, alpha and beta may be encoded by the same gene, since alpha appeared to be a truncated form of beta. Alanine, the first amino acid residue at the N-terminal end of beta was not present at this position in alpha. Otherwise the sequences of alpha and beta appeared to be identical. The calculated molecular masses of the sequenced part of alpha and beta were 2426 and 2497 Da, respectively. The molecular masses of alpha and beta as determined by mass spectroscopy were 2687 +/- 30 and 2758 +/- 30 Da, respectively, indicating that (i) the only difference between alpha and beta was the presence of the N-terminal alanine residue in beta, and that (ii) in addition to the sequenced residues, two to three unidentified amino acid residues are present at the C-terminal ends of the alpha and beta peptides.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Bacteriocinas/isolamento & purificação , Lactobacillus/química , Sequência de Aminoácidos , Bacteriocinas/genética , Bacteriocinas/farmacologia , Lactobacillus/genética , Espectrometria de Massas , Dados de Sequência Molecular , Peso Molecular , Peptídeos/genética , Peptídeos/isolamento & purificação , Peptídeos/farmacologia
8.
J Appl Bacteriol ; 75(2): 113-22, 1993 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-8407671

RESUMO

Three hundred and thirty-five lactic acid bacteria were isolated from sour doughs and screened for antagonistic activity. Of these 145 showed activity against one or several of the indicator strains used in the screening. The antimicrobial activity of 18 isolates were due to a proteinaceous compound. These 18 isolates belonged to three different Lactobacillus species: Lactobacillus bavaricus, Lactobacillus curvatus and Lactobacillus plantarum. The spectrum of antimicrobial activity for the three species suggested that the inhibitory components were different. The inhibitory compound from Lact. bavaricus MI401 was chosen for further study. The proteinaceous nature, antimicrobial activity against closely-related species, heat resistance and sensitivity to alkaline treatment strongly indicated that this substance was a bacteriocin, which we designated bavaricin A. The bacteriocin was purified to homogeneity by ammonium sulphate precipitation, ion exchange, hydrophobic interaction and reverse-phase chromatography. The purification resulted in 193,000-fold increase in specific activity. SDS-PAGE of bavaricin A showed a molecular weight of 3500-4000 Da. By amino acid sequencing 41 amino acids were determined. Bavaricin A had a bactericidal mode of action and inhibited nine out of 10 Listeria monocytogenes. Lactobacillus bavaricus MI401 produced bavaricin A at temperatures from 4 degrees C to 30 degrees C. The production of active bavaracin A was inhibited at increasing sodium chloride concentration. In the presence of 3% sodium chloride at 4 degrees C no active bavaricin A could be detected. Nitrite (100 ppm) did not affect the production of active bavaricin A.


Assuntos
Bacteriocinas/isolamento & purificação , Pão/microbiologia , Lactobacillus/metabolismo , Sequência de Aminoácidos , Bacteriocinas/biossíntese , Bacteriocinas/farmacologia , Testes de Sensibilidade Microbiana , Dados de Sequência Molecular , Homologia de Sequência de Aminoácidos
9.
Biochem J ; 203(2): 511-3, 1982 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-6288004

RESUMO

Zn2+ inhibits purified poly(ADP-ribose) polymerase (50% inhibition at 10 microM). Furthermore poly (ADP-ribose) polymerase present in nuclei and metaphase chromosome clusters is also inhibited by Zn2+. The inactivated enzyme could be re-activated by dithiothreitol. The concentration of Zn2+ needed to affect the enzyme activity in the organelles is sufficiently low for it to have a possible role in controlling the activity of this chromatin-bound enzyme.


Assuntos
NAD+ Nucleosidase/antagonistas & inibidores , Inibidores de Poli(ADP-Ribose) Polimerases , Zinco/farmacologia , Animais , Núcleo Celular/enzimologia , Cromossomos/enzimologia , Ditiotreitol/farmacologia , Ativação Enzimática/efeitos dos fármacos , Células HeLa/enzimologia , Humanos , Metáfase , Suínos , Timo/enzimologia
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