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1.
Nat Med ; 30(3): 716-729, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38351187

RESUMEN

For patients with non-small-cell lung cancer (NSCLC) tumors without currently targetable molecular alterations, standard-of-care treatment is immunotherapy with anti-PD-(L)1 checkpoint inhibitors, alone or with platinum-doublet therapy. However, not all patients derive durable benefit and resistance to immune checkpoint blockade is common. Understanding mechanisms of resistance-which can include defects in DNA damage response and repair pathways, alterations or functional mutations in STK11/LKB1, alterations in antigen-presentation pathways, and immunosuppressive cellular subsets within the tumor microenvironment-and developing effective therapies to overcome them, remains an unmet need. Here the phase 2 umbrella HUDSON study evaluated rational combination regimens for advanced NSCLC following failure of anti-PD-(L)1-containing immunotherapy and platinum-doublet therapy. A total of 268 patients received durvalumab (anti-PD-L1 monoclonal antibody)-ceralasertib (ATR kinase inhibitor), durvalumab-olaparib (PARP inhibitor), durvalumab-danvatirsen (STAT3 antisense oligonucleotide) or durvalumab-oleclumab (anti-CD73 monoclonal antibody). Greatest clinical benefit was observed with durvalumab-ceralasertib; objective response rate (primary outcome) was 13.9% (11/79) versus 2.6% (5/189) with other regimens, pooled, median progression-free survival (secondary outcome) was 5.8 (80% confidence interval 4.6-7.4) versus 2.7 (1.8-2.8) months, and median overall survival (secondary outcome) was 17.4 (14.1-20.3) versus 9.4 (7.5-10.6) months. Benefit with durvalumab-ceralasertib was consistent across known immunotherapy-refractory subgroups. In ATM-altered patients hypothesized to harbor vulnerability to ATR inhibition, objective response rate was 26.1% (6/23) and median progression-free survival/median overall survival were 8.4/22.8 months. Durvalumab-ceralasertib safety/tolerability profile was manageable. Biomarker analyses suggested that anti-PD-L1/ATR inhibition induced immune changes that reinvigorated antitumor immunity. Durvalumab-ceralasertib is under further investigation in immunotherapy-refractory NSCLC.ClinicalTrials.gov identifier: NCT03334617.


Asunto(s)
Antineoplásicos , Carcinoma de Pulmón de Células no Pequeñas , Indoles , Neoplasias Pulmonares , Morfolinas , Pirimidinas , Sulfonamidas , Humanos , Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Carcinoma de Pulmón de Células no Pequeñas/genética , Neoplasias Pulmonares/tratamiento farmacológico , Neoplasias Pulmonares/genética , Platino (Metal)/uso terapéutico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Anticuerpos Monoclonales , Antineoplásicos/uso terapéutico , Biomarcadores , Antígeno B7-H1 , Microambiente Tumoral
2.
J Cell Mol Med ; 12(2): 479-95, 2008 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-18194455

RESUMEN

Changes in protein subdomains through alternative splicing often modify protein-protein interactions, altering biological processes. A relevant example is that of the stress-induced up-regulation of the acetylcholinesterase (AChE-R) splice variant, a common response in various tissues. In germ cells of male transgenic TgR mice, AChE-R excess associates with reduced sperm differentiation and sperm counts. To explore the mechanism(s) by which AChE-R up-regulation affects spermatogenesis, we identified AChE-R's protein partners through a yeast two-hybrid screen. In meiotic spermatocytes from TgR mice, we detected AChE-R interaction with the scaffold protein RACK1 and elevated apoptosis. This correlated with reduced scavenging by RACK1 of the pro-apoptotic TAp73, an outcome compatible with the increased apoptosis. In contrast, at later stages in sperm development, AChE-R's interaction with the glycolytic enzyme enolase-alpha elevates enolase activity. In transfected cells, enforced AChE-R excess increased glucose uptake and adenosine tri-phosphate (ATP) levels. Correspondingly, TgR sperm cells display elevated ATP levels, mitochondrial hyperactivity and increased motility. In human donors' sperm, we found direct association of sperm motility with AChE-R expression. Interchanging interactions with RACK1 and enolase-alpha may hence enable AChE-R to affect both sperm differentiation and function by participating in independent cellular pathways.


Asunto(s)
Acetilcolinesterasa/metabolismo , Apoptosis , Motilidad Espermática , Espermatozoides/enzimología , Espermatozoides/fisiología , Acetilcolinesterasa/genética , Empalme Alternativo , Animales , Apoptosis/genética , Biopsia , Humanos , Inmunohistoquímica , Masculino , Ratones , Ratones Transgénicos , Modelos Biológicos , Motilidad Espermática/genética , Espermatozoides/citología , Testículo/citología , Testículo/enzimología , Testículo/metabolismo , Testículo/fisiología , Testículo/cirugía
3.
Biotechnol Bioeng ; 75(3): 259-66, 2001 Nov 05.
Artículo en Inglés | MEDLINE | ID: mdl-11590598

RESUMEN

Enzyme therapy for the prevention and treatment of organophosphate poisoning depends on the availability of large amounts of cholinesterases. Transgenic plants are being evaluated for their efficiency and cost-effectiveness as a system for the bioproduction of therapeutically valuable proteins. Here we report production of a recombinant isoform of human acetylcholinesterase in transgenic tomato plants. Active and stable acetylcholinesterase, which retains the kinetic characteristics of the human enzyme, accumulated in tomato plants. High levels of specific activity were registered in leaves (up to 25 nmol min(-1) mg protein(-1)) and fruits (up to 250 nmol min(-1) mg protein(-1)).


Asunto(s)
Acetilcolinesterasa/genética , Solanum lycopersicum/genética , Acetilcolinesterasa/metabolismo , Secuencia de Bases , Northern Blotting , Southern Blotting , Cartilla de ADN , Electroforesis en Gel de Poliacrilamida , Humanos , Cinética , Hojas de la Planta/enzimología , Plantas Modificadas Genéticamente/genética , Reacción en Cadena de la Polimerasa , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo
4.
Small Rumin Res ; 39(2): 107-112, 2001 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-11182302

RESUMEN

Bacterial pathogens causing udder infections in Israeli Assaf dairy sheep were identified and changes occurring throughout lactation were monitored to study the correlation between the contaminant and the severity of the infection, as measured by somatic cell count (SCC) and NAGase tests. A total of 159 Israeli Assaf dairy sheep on one farm, in their first (69), second (13) or third and more (77) lactations were included in this study. Udder halves were tested for bacterial condition, SCC and NAGase activity 2-3 weeks post lambing and every 4 weeks after until drying-off. At first sampling, in 60.7% (193/318 quarters) of the halves no bacterial growth (NBG) was detected. Different species of coagulase negative staphylococci (CNS) were the main pathogen group in infected udders. Streptococci were isolated from 14 halves, most of them in the two udder halves. The percent of udder infection in sheep in their third or further lactations was 2.8 greater (P<0.05) than in that of sheep in their first lactation. During the lactation, 90.6% of the halves did not change their classification status, suggesting that most infections occur before lambing and/or during the following first few days. The arithmetic mean of SCC and NAGase of total half udder milk and samplings (during the lactation) were 1144+/-48x10(3)cells/ml and 49.4+/-2.5, respectively. The average SCC in the milk of halves classified as NBG was 321+/-35x10(3)cells/ml and was not significantly changed during the lactation period. In halves infected with CNS, average SCC was 1371+/-150x10(3)cells/ml at the first testing and increased to 2129+/-347x10(3)cells/ml at drying-off. No significant differences were found in SCC and NAGase activity between the different species of the CNS. The mean SCC over the types of bacteria isolated, lactation number and days in lactation was significantly different (P<0.0001). In 4% of the halves, from all samples, SCC was above 5000x10(3)cells/ml although no bacteria were detected in their milk. The higher SCC in the CNS infected halves contrasted with the more moderate SCC found in dairy cows similarly infected, suggesting that the sheep udder has a lower resistance and an augmented immunological response against this group of bacteria. Thus, this should be considered accordingly in schemes for sheep's milk quality payment.

5.
Phys Rev Lett ; 85(6): 1330-3, 2000 Aug 07.
Artículo en Inglés | MEDLINE | ID: mdl-10991544

RESUMEN

We provide limits to practical quantum key distribution, taking into account channel losses, a realistic detection process, and imperfections in the "qubits" sent from the sender to the receiver. As we show, even quantum key distribution with perfect qubits might not be achievable over long distances when the other imperfections are taken into account. Furthermore, existing experimental schemes (based on weak pulses) currently do not offer unconditional security for the reported distances and signal strength. Finally we show that parametric down-conversion offers enhanced performance compared to its weak coherent pulse counterpart.

6.
J Food Prot ; 63(7): 970-3, 2000 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-10914671

RESUMEN

The activities and rates of inactivation of four enzymes in raw buffalo milk were measured in relation to the process of heating to determine the value of these enzymes as markers for the evaluation of milk pasteurization. The activities of the enzymes alkaline phosphatase (ALP), lactic dehydrogenase (LDH), gamma-glutamyltransferase (GGT), and aspartate aminotransferase (AST) were measured before and after heating at 50, 60, 70, and 80 degrees C for 1, 3, 5, 10, 20, and 30 min. The enzyme GGT showed the highest activity (712 +/- 601 IU/liter), followed by LDH (386 +/- 183 IU/liter), ALP (295 +/- 164 IU/liter), and AST (18 +/- 4 IU/liter). Heating the milk at 50 degrees C for 1 to 30 min resulted in no effect on the activity of any of the enzymes. At 60 degrees C, ALP showed the highest sensitivity to heat inactivation, whereas all other enzymes showed resistance. At 70 degrees C, ALP activity was abolished completely after 1 min, whereas GGT and LDH lost most activity after 10 min, and AST still maintained 50% activity even after 30 min. At 80 degrees C, the activities of LDH and GGT were lost, whereas AST still retained some of its activity. The results suggest that in addition to ALP, LDH and GGT, but not AST, are potential markers for heat denaturation in buffalo milk, with GGT having the advantage that its concentration is the highest.


Asunto(s)
Microbiología de Alimentos , Calor , Leche/enzimología , Esterilización , Fosfatasa Alcalina/metabolismo , Animales , Aspartato Aminotransferasas/metabolismo , Búfalos , Isoenzimas , L-Lactato Deshidrogenasa/metabolismo , Leche/microbiología , gamma-Glutamiltransferasa/metabolismo
7.
Trends Microbiol ; 6(11): 449-53, 1998 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-9846363

RESUMEN

In addition to their traditional role as a source of natural medicines, it is now possible to genetically engineer plants to produce pharmaceuticals. Transgenic plants expressing antigens from pathogenic microorganisms offer many advantages as low-cost production systems and effective delivery systems for vaccines. This new technology might contribute to global vaccine programs and might have a dramatic impact on health care in developing countries.


Asunto(s)
Vacunas Bacterianas/inmunología , Plantas Modificadas Genéticamente , Vacunas de ADN/inmunología , Vacunas Virales/inmunología , Administración Oral , Animales , Antígenos Bacterianos/genética , Antígenos Bacterianos/inmunología , Antígenos Virales/genética , Antígenos Virales/inmunología , Vacunas Bacterianas/genética , Humanos , Plantas Modificadas Genéticamente/inmunología , Vacunas Virales/genética
8.
Phys Rev A ; 54(4): 2651-2658, 1996 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-9913773
9.
Phys Rev A ; 54(4): 2675-2684, 1996 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-9913776
10.
Mol Gen Genet ; 246(5): 600-4, 1995 Mar 10.
Artículo en Inglés | MEDLINE | ID: mdl-7700232

RESUMEN

The psbE and psbF genes encode the apoproteins of cytochrome b559, an essential component of the pigment protein complex photosystem II. Together with psbL and psbJ, these genes constitute a single operon in all photosynthetic organisms examined thus far. We have cloned and sequenced the psbE and psbF genes of the Chlamydomonas reinhardtii plastid genome. The predicted amino-terminal domains of both polypeptides are more basic than those of other organisms, and the sequence of the psbE gene product indicates a departure from the 'positive-inside' rule for the insertion of proteins in the thylakoid membrane. Northern blot analysis demonstrated that psbE is transcribed into a 0.3 kb mRNA, while transcription of psbF and psbL genes results in a 0.9 kb transcript. The splitting of the psbEFLJ operon into separate transcription units suggests a unique mechanism of regulation of expression of these genes in C. reinhardtii.


Asunto(s)
Apoproteínas/genética , Chlamydomonas reinhardtii/genética , Grupo Citocromo b/genética , Genes Protozoarios/genética , Complejo de Proteína del Fotosistema II , Plastidios/genética , Transcripción Genética/genética , Secuencia de Aminoácidos , Animales , Apoproteínas/química , Secuencia de Bases , Clonación Molecular , Grupo Citocromo b/química , Datos de Secuencia Molecular , Operón/genética , ARN Mensajero/genética , ARN Protozoario/genética , Mapeo Restrictivo , Alineación de Secuencia , Análisis de Secuencia de ADN
11.
Phys Rev A ; 51(3): 1863-1869, 1995 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-9911795
12.
Proc Natl Acad Sci U S A ; 91(17): 8082-6, 1994 Aug 16.
Artículo en Inglés | MEDLINE | ID: mdl-8058761

RESUMEN

The D1 protein of the photosystem II (PSII) complex in the thylakoid membrane of oxygenic photosynthetic organisms is synthesized as a precursor polypeptide (pD1) with a C-terminal extension. Posttranslational processing of the pD1 protein is essential to establish water oxidation activity of the PSII complex. We have recently identified a gene, ctpA, a mutation in which resulted in a loss of PSII activity in the cyanobacterium Synechocystis sp. PCC 6803. To study the function of the CtpA protein, we inactivated the ctpA gene by inserting a kanamycin-resistance gene into its coding sequence. The resultant mutant strain, T564, had no PSII-mediated water oxidation activity, but it had normal cytochrome b6f and photosystem I activities. Measurements of thermoluminescence profiles and rates of reduction of 2,6-dichlorophenolindophenol indicated that PSII complexes in the mutant cells had functional reaction centers that were unable to accept electrons from water. Immunoblot analysis showed that D1, D2, CP47, CP43, and the alpha subunit of cytochrome b559, five integral membrane proteins of PSII, were present in T564 cells. Interestingly, the D1 protein in the mutant cells was 2 kDa larger than that in wild-type cells, due to the presence of a C-terminal extension. We conclude that the CtpA protein is a processing enzyme that cleaves off the C-terminal extension of the D1 protein. Interestingly, the CtpA protein shows significant sequence similarity to the interphotoreceptor retinoid-binding proteins in the bovine, human, and insect eye systems.


Asunto(s)
Proteínas Bacterianas/biosíntesis , Carboxipeptidasas , Cianobacterias/metabolismo , Endopeptidasas/biosíntesis , Genes de Plantas , Proteínas del Complejo del Centro de Reacción Fotosintética/biosíntesis , Proteínas de Plantas/biosíntesis , Proproteína Convertasas , Proteínas Algáceas , Secuencia de Aminoácidos , Proteínas Bacterianas/análisis , Endopeptidasas/análisis , Endopeptidasas/genética , Immunoblotting , Datos de Secuencia Molecular , Mutagénesis Insercional , Complejo de Proteína del Fotosistema I , Complejo de Proteína del Fotosistema II , Proteínas de Plantas/análisis , Mapeo Restrictivo , Homología de Secuencia de Aminoácido
13.
Arerugi ; 39(4): 418-23, 1990 Apr.
Artículo en Japonés | MEDLINE | ID: mdl-2383183

RESUMEN

Acute hepatic necrosis was induced by a single i.v. injection of lipopolysaccharide (LPS) into C57BL/6 mice following immunization with syngeneic liver protein and adjuvant. Sixty percent of the mice died of massive hepatocyte necrosis within 48 hours of LPS injection. The serum lactate dehydrogenase and aspartate aminotransferase levels were markedly elevated. The fatal and hepatotoxic action of LPS was prevented by pretreatment with FUT-175 (1.6 mg/kg), a synthetic protease-inhibitor. The inhibitory effects of FUT-175 was not demonstrated when the agent was given to the mice 2 h after the administration of LPS. These results seem to indicate that the hepatotoxic effects of LPS are mediated by endogenous host mechanisms in which proteases play an important role.


Asunto(s)
Enfermedad Hepática Inducida por Sustancias y Drogas/prevención & control , Guanidinas/uso terapéutico , Hígado/patología , Inhibidores de Proteasas/uso terapéutico , Adyuvantes Inmunológicos , Animales , Benzamidinas , Enfermedad Hepática Inducida por Sustancias y Drogas/patología , Relación Dosis-Respuesta a Droga , Guanidinas/administración & dosificación , Lipopolisacáridos , Ratones , Ratones Endogámicos C57BL , Necrosis , Factores de Tiempo
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