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BACKGROUND: The difference in diagnostic yield between surgical lung biopsy and transbronchial lung cryobiopsy (TBLC) in diffuse parenchymal lung diseases (DPLD) has been reported to be due to differences in the rate of interpathologist agreement, specimen size, and specimen adequacy. In TBLC, the specimens containing large airway components are generally believed as inadequate specimens for histological evaluation, but the detailed characteristics of TBLC specimens including the large airway and the impact on histological diagnostic rates of DPLD have not been investigated. METHODS: We retrospectively reviewed the specimen characteristics of patients with DPLD who underwent TBLC. RESULTS: Between February 2018 and January 2020, 74 patients and 177 specimens were included. There were 85 (48.0%) large airway specimens (LAS) that contained bronchial gland or bronchial cartilage. The ideal specimen ratio was significantly lower in the LAS-positive group than that in the LAS-negative group (5.8% vs. 45.6%), and the proportion of bronchioles, alveoli, and perilobular area were similarly lower in the LAS-positive group. The presence of traction bronchiectasis and diaphragm overlap sign on high-resolution computed tomography (HRCT) were also significantly higher in the LAS-positive group than those in the LAS-negative group. We observed a statistically significant trend in histological diagnostic yield (40.7% in LAS positive group; 60.8% in LAS positive and negative group; 91.6% in LAS negative group) (Cochran-Armitage trend test). CONCLUSION: LAS is a specimen often collected in TBLC and contains a low percentage of bronchioles, alveoli, and perilobular area. Since the histological diagnostic yield tends to be higher in cases that do not contain LAS, it may be important to determine the biopsy site that reduces the frequency of LAS collection by referring to the HRCT findings in TBLC.
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Broncoscopía , Enfermedades Pulmonares Intersticiales , Humanos , Broncoscopía/métodos , Estudios Retrospectivos , Enfermedades Pulmonares Intersticiales/diagnóstico , Enfermedades Pulmonares Intersticiales/patología , Pulmón/diagnóstico por imagen , Pulmón/patología , Biopsia/métodosRESUMEN
Ultrafast electronic-phase change in solids by light, called photoinduced phase transition, is a central issue in the field of non-equilibrium quantum physics, which has been developed very recently. In most of those phenomena, charge or spin orders in an original phase are melted by photocarrier generations, while an ordered state is usually difficult to be created from a non-ordered state by a photoexcitation. Here, we demonstrate that a strong terahertz electric-field pulse changes a Mott insulator of an organic molecular compound in κ-(ET)2Cu[N(CN)2]Cl (ET = bis(ethylenedithio)tetrathiafulvalene), to a macroscopically polarized charge-order state; herein, electronic ferroelectricity is induced by the collective intermolecular charge transfers in each dimer. In contrast, in an isostructural compound, κ-(ET)2Cu2(CN)3, which shows the spin-liquid state at low temperatures, a similar polar charge order is not stabilized by the same terahertz pulse. From the comparative studies of terahertz-field-induced second-harmonic-generation and reflectivity changes in the two compounds, we suggest the possibility that a coupling of charge and spin degrees of freedom would play important roles in the stabilization of polar charge order.
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BACKGROUND: Pulmonary alveolar proteinosis (PAP) is characterized by the accumulation of surfactant proteins within the alveolar spaces. Autoimmune PAP (APAP) caused by elevated levels of GM-CSF autoantibodies (GM-Ab) is very rarely associated with systemic autoimmune disease. Here we report a case of APAP manifested during immunosuppressive treatment for polymyositis with interstitial lung disease. CASE PRESENTATION: A 52-year-old woman treated at our hospital because of polymyositis with interstitial pneumonia had maintained remission by immunosuppressive treatment for 15 years. She had progressive dyspnea subsequently over several months with her chest CT showing ground-glass opacities (GGO) in bilateral geographic distribution. Her bronchoalveolar lavage fluid with cloudy appearance revealed medium-sized foamy macrophages and PAS-positive amorphous eosinophilic materials by cytological examination. We diagnosed her as APAP due to an increased serum GM-CSF autoantibody level. Attenuating immunosuppression failed to lead GGO improvement, but whole lung lavage (WLL) was effective in her condition. CONCLUSIONS: PAP should be considered as one of the differential diseases when the newly interstitial shadow was observed during immunosuppressive treatment. WLL should be regarded as the treatment option for APAP concurred in connective tissue disease (CTD).
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Autoanticuerpos/sangre , Enfermedades Autoinmunes/diagnóstico , Enfermedades Pulmonares Intersticiales/complicaciones , Polimiositis/complicaciones , Proteinosis Alveolar Pulmonar/diagnóstico , Enfermedades Autoinmunes/inmunología , Enfermedades Autoinmunes/fisiopatología , Líquido del Lavado Bronquioalveolar/citología , Disnea/etiología , Femenino , Factor Estimulante de Colonias de Granulocitos y Macrófagos/inmunología , Humanos , Inmunosupresores/efectos adversos , Pulmón/fisiopatología , Enfermedades Pulmonares Intersticiales/tratamiento farmacológico , Persona de Mediana Edad , Polimiositis/tratamiento farmacológico , Proteinosis Alveolar Pulmonar/inmunología , Proteinosis Alveolar Pulmonar/fisiopatología , Proteinosis Alveolar Pulmonar/terapia , Tomografía Computarizada por Rayos XRESUMEN
Coupling of charge and spin degrees of freedom is a critical feature of correlated electron oxides, as represented by the spin-related mechanism of a Cooper pair under high-T c superconductivity. A doublon-holon pair generated on an antiferromagnetic spin background is also predicted to attract each other via the spin-spin interaction J, similar to a Cooper pair, while its evidence is difficult to obtain experimentally. Here, we investigate such an excitonic effect by electroreflectance spectroscopy using terahertz electric field pulses in undoped cuprates: Nd2CuO4, Sr2CuO2Cl2, and La2CuO4. Analyses of the spectral changes of reflectivity under electric fields reveal that the splitting of odd-parity and even-parity excitons, a measure of doublon-holon binding energy, increases with J. This trend is reproduced by t-J-type model calculations, providing strong evidence of the spin-related doublon-holon pairing. Agreement with the calculations supports the s-wave symmetry of the doublon-holon pair in contrast to the d-wave Cooper pair in doped cuprates.
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Rapid polarization control by an electric field in ferroelectrics is important to realize high-frequency modulation of light, which has potential applications in optical communications. To achieve this, a key strategy is to use an electronic part of ferroelectric polarization. A hydrogen-bonded molecular ferroelectric, croconic acid, is a good candidate, since π-electron polarization within each molecule is theoretically predicted to play a significant role in the ferroelectric-state formation, as well as the proton displacements. Here, we show that a sub-picosecond polarization modulation is possible in croconic acid using a terahertz pulse. The terahertz-pulse-pump second-harmonic-generation-probe and optical-reflectivity-probe spectroscopy reveal that the amplitude of polarization modulation reaches 10% via the electric-field-induced modifications of π-electron wavefunctions. Moreover, the measurement of electric-field-induced changes in the infrared molecular vibrational spectrum elucidates that the contribution of proton displacements to the polarization modulation is negligibly small. These results demonstrate the electronic nature of polarization in hydrogen-bonded molecular ferroelectrics. The ultrafast polarization control via π-electron systems observed in croconic acid is expected to be possible in many other hydrogen-bonded molecular ferroelectrics and utilized for future high-speed optical-modulation devices.
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The transition of a Mott insulator to metal, the Mott transition, can occur via carrier doping by elemental substitution, and by photoirradiation, as observed in transition-metal compounds and in organic materials. Here, we show that the application of a strong electric field can induce a Mott transition by a new pathway, namely through impulsive dielectric breakdown. Irradiation of a terahertz electric-field pulse on an ET-based compound, κ-(ET) 2Cu[N(CN) 2]Br (ET:bis(ethylenedithio)tetrathiafulvalene), collapses the original Mott gap of â¼30 meV with a â¼0.1 ps time constant after doublon-holon pair productions by quantum tunnelling processes, as indicated by the nonlinear increase of Drude-like low-energy spectral weights. Additionally, we demonstrate metallization using this method is faster than that by a femtosecond laser-pulse irradiation and that the transition dynamics are more electronic and coherent. Thus, strong terahertz-pulse irradiation is an effective approach to achieve a purely electronic Mott transition, enhancing the understanding of its quantum nature.
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Standing-up motion is an important daily activity. It has been known that elderly and post-stroke patients have difficulty in performing standing-up motion. The standing-up motion is retrained by therapists to maximize independence of the elderly and post-stroke patients, but it is not clear how the elderly and post-stroke patients control their redundant muscles to achieve standing-up motion. This study employed the concept of muscle synergy to analyze how healthy young adults, healthy elderly people and post-stroke patients control their muscles. Experimental result verified that four muscle synergies can represent human standing-up motion. In addition, it indicated that the post-stroke patients shift the weights of muscle synergies to finish standing-up motion comparing to healthy subjects. Moreover, different muscle synergy structures were associated with the CoM and joint kinematics.
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Fenómenos Biomecánicos/fisiología , Músculo Esquelético/fisiología , Equilibrio Postural/fisiología , Accidente Cerebrovascular/fisiopatología , Adulto , Anciano , Humanos , Persona de Mediana Edad , Adulto JovenRESUMEN
A rapid polarization control in paraelectric materials is important for an ultrafast optical switching useful in the future optical communication. In this study, we applied terahertz-pump second-harmonic-generation-probe and optical-reflectivity-probe spectroscopies to the paraelectric neutral phase of an organic molecular dielectric, tetrathiafulvalene-p-chloranil and revealed that a terahertz pulse with the electric-field amplitude of â¼400 kV/cm produces in the subpicosecond time scale a large macroscopic polarization whose magnitude reaches â¼20% of that in the ferroelectric ionic phase. Such a large polarization generation is attributed to the intermolecular charge transfers and breathing motions of domain walls between microscopic neutral and ionic domains induced by the terahertz electric field.
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In electronic-type ferroelectrics, where dipole moments produced by the variations of electron configurations are aligned, the polarization is expected to be rapidly controlled by electric fields. Such a feature can be used for high-speed electric-switching and memory devices. Electronic-type ferroelectrics include charge degrees of freedom, so that they are sometimes conductive, complicating dielectric measurements. This makes difficult the exploration of electronic-type ferroelectrics and the understanding of their ferroelectric nature. Here, we show unambiguous evidence for electronic ferroelectricity in the charge-order (CO) phase of a prototypical ET-based molecular compound, α-(ET)2I3 (ET:bis(ethylenedithio)tetrathiafulvalene), using a terahertz pulse as an external electric field. Terahertz-pump second-harmonic-generation(SHG)-probe and optical-reflectivity-probe spectroscopy reveal that the ferroelectric polarization originates from intermolecular charge transfers and is inclined 27° from the horizontal CO stripe. These features are qualitatively reproduced by the density-functional-theory calculation. After sub-picosecond polarization modulation by terahertz fields, prominent oscillations appear in the reflectivity but not in the SHG-probe results, suggesting that the CO is coupled with molecular displacements, while the ferroelectricity is electronic in nature. The results presented here demonstrate that terahertz-pump optical-probe spectroscopy is a powerful tool not only for rapidly controlling polarizations, but also for clarifying the mechanisms of ferroelectricity.
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SUMMARY: We present 3 cases of extracranial head and neck schwannomas exhibiting fluid-fluid levels. In the described cases, CT and MR imaging showed predominantly cystic components, intermixed with cellular components. Histopathologic examinations of excised specimens revealed hemosiderin deposition, reflecting intratumoral hemorrhages, which was presumably a cause of fluid-fluid levels. Although fluid-fluid levels are nonspecific findings, schwannoma should be considered when radiologic images demonstrate marked cystic formation with fluid-fluid levels in extracranial head and neck tumors.
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Líquido Quístico/citología , Líquido Quístico/diagnóstico por imagen , Neoplasias de Cabeza y Cuello/diagnóstico , Imagen por Resonancia Magnética/métodos , Neurilemoma/diagnóstico , Tomografía Computarizada por Rayos X/métodos , Adulto , Anciano de 80 o más Años , Neoplasias Encefálicas/diagnóstico , Femenino , Humanos , Masculino , Persona de Mediana EdadRESUMEN
BACKGROUND: Although the aetiology of moyamoya disease (MMD) has not been fully clarified, genetic analysis of familial MMD (F-MMD) has considerable potential to disclose it. OBJECTIVE: To determine the inheritance pattern and clinical characteristics of F-MMD to enable precise genetic analyses of the disease. METHODS: 15 highly aggregated Japanese families (52 patients; 38 women and 14 men) with three or more affected members were examined. The difference in categories of age at onset (child onset, adult onset and asymptomatic) between paternal and maternal transmission was compared by chi2 statistics. RESULTS: In all families there had been three or more generations without consanguinity, and all types of transmission, including father-to-son, were observed. Among a total of 135 offspring of affected people, 59 (43.7%) were patients with MMD or obligatory carriers. Affected mothers were more likely to produce late-onset (adult-onset or asymptomatic) female offspring (p = 0.007). CONCLUSIONS: The mode of inheritance of F-MMD is autosomal dominant with incomplete penetrance. Thus, in future genetic studies on F-MMD, parametric linkage analyses using large families with an autosomal dominant mode of inheritance are recommended. Genomic imprinting may be associated with the disease.
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Genes Dominantes , Enfermedad de Moyamoya/genética , Adolescente , Adulto , Edad de Inicio , Anciano , Niño , Preescolar , Femenino , Humanos , Masculino , Persona de Mediana Edad , Linaje , PenetranciaRESUMEN
Recent progress in high-throughput screening technologies has led to the production of massive amounts data that we can use to understand biological systems. To interpret this data, biologists often need to analyze the characteristics of a set of genes by using Gene Ontology (GO) annotation. We are proposing a novel method for assisting such an analysis. Given a set of genes, the method automatically extracts several analyzing aspects in terms of a subset of genes that are attached to some related GO terms. It then creates a gene-attribute bipartite graph that highlights the aspect selected by the user according to his/her interests. We describe this method in detail and report on an experiment where the proposed method is applied to the analysis of rat kidney expression data.
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Genes , Modelos Genéticos , Animales , Biología Computacional/métodos , Regulación del Desarrollo de la Expresión Génica , Riñón/embriología , ProbabilidadRESUMEN
We report two instructive cases of ruptured dissecting aneurysm of the basilar artery. Although stent-assisted endovascular treatment was successful, recurrent bleeding occurred 4 h after the procedure in one patient, and the other's basilar artery occluded 6 days after the procedure. These cases suggest that the high porosity of currently available stents may be insufficient to induce intraluminal thrombosis and merely stenting may fail to prevent bleeding, while postoperative anticoagulation alone may be inadequate to prevent occlusion of the stented vessel.
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Aneurisma Roto/terapia , Disección Aórtica/terapia , Arteria Basilar , Aneurisma Intracraneal/terapia , Stents , Adulto , Disección Aórtica/diagnóstico por imagen , Aneurisma Roto/diagnóstico por imagen , Angiografía , Femenino , Humanos , Aneurisma Intracraneal/diagnóstico por imagen , Masculino , Persona de Mediana Edad , Radiografía Intervencional , Insuficiencia del TratamientoRESUMEN
Three patients with bleeding-type moyamoya disease suffered ischemic complications following their first episode of intracranial bleeding. The patients presented with intraventricular hemorrhage and suffered cerebral infarction on the 14th, 16th, and 11th days after the ictus, respectively. The clinical records revealed no obvious hypotension before progression to infarction and suggested that dehydration accelerated by the administration of hyperosmotic drugs was a contributing factor to the infarction. Two patients underwent superficial temporal artery-middle cerebral artery anastomoses in the chronic stages and have never experienced further ischemic complications. The other patient died despite receiving intensive care. Hemodynamic reserve may be severely impaired in patients with bleeding-type moyamoya disease. Adequate control of hydration is important to prevent cerebral infarction after intracranial bleeding in patients with moyamoya disease.
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Isquemia Encefálica/etiología , Hemorragia Cerebral/complicaciones , Enfermedad de Moyamoya/complicaciones , Adolescente , Isquemia Encefálica/diagnóstico , Isquemia Encefálica/cirugía , Hemorragia Cerebral/diagnóstico , Hemorragia Cerebral/cirugía , Infarto Cerebral/diagnóstico , Infarto Cerebral/etiología , Infarto Cerebral/cirugía , Revascularización Cerebral , Ventrículos Cerebrales/patología , Niño , Diagnóstico Diferencial , Diagnóstico por Imagen , Resultado Fatal , Femenino , Humanos , Masculino , Persona de Mediana Edad , Enfermedad de Moyamoya/diagnóstico , Enfermedad de Moyamoya/cirugíaRESUMEN
OBJECTIVE: To determine the relationship between the expression of interleukin-1beta (IL-1beta) and IL-1 receptor antagonists (IL-1ra) in the subacromial bursa and shoulder pain in rotator cuff diseases. METHODS: Synovial specimens were analysed using various methods including reverse transcriptase-polymerase chain reaction (RT-PCR), immunohistochemistry and in situ RT-PCR. Thirty-nine patients with rotator cuff diseases were candidates. The degree of their shoulder pain was evaluated using a visual analogue scale. RESULTS: The mRNA expression levels of the cytokines were significantly correlated with the degree of pain [IL-1beta: r=0.782; secreted IL-1ra (sIL-1ra): r=0.756; intracellular IL-1ra (icIL-1ra): r=0.806, P<0.001, respectively]. The combined results of immunohistochemistry and in situ RT-PCR analysis indicated that both synovial lining and sublining cells produce IL-1beta, while synovial lining cells predominantly produce icIL-1ra and sublining cells secrete sIL-1ra. CONCLUSIONS: The differential regulation of the two forms of IL-1ra mRNAs may play an important role in shoulder pain in rotator cuff diseases, regulating IL-1-induced subacromial synovitis.
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Interleucina-1/metabolismo , Manguito de los Rotadores/metabolismo , Síndrome de Abducción Dolorosa del Hombro/metabolismo , Dolor de Hombro/metabolismo , Sinovitis/metabolismo , Adulto , Anciano , Bolsa Sinovial/metabolismo , Bolsa Sinovial/patología , Humanos , Técnicas para Inmunoenzimas , Proteína Antagonista del Receptor de Interleucina 1 , Interleucina-1/genética , Persona de Mediana Edad , Dimensión del Dolor , ARN/análisis , ARN Mensajero/metabolismo , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Manguito de los Rotadores/fisiopatología , Síndrome de Abducción Dolorosa del Hombro/complicaciones , Síndrome de Abducción Dolorosa del Hombro/fisiopatología , Dolor de Hombro/etiología , Sialoglicoproteínas/genética , Sialoglicoproteínas/metabolismo , Membrana Sinovial/metabolismo , Membrana Sinovial/patología , Sinovitis/fisiopatologíaRESUMEN
Although clinically significant, much remains unknown about the healing of the torn rotator cuff tendon, because of unavailability of appropriate animal model. The human supraspinatus tendon faces the subacromial bursa superiorly, and the joint capsule inferiorly, while the digital flexor tendon is surrounded by the synovium. We hypothesized that the supraspinatus tendon heals by the process which is different from that observed with digital flexor tendons, in which epitenon cells migrate into the torn portion circumferentially. The avian supracoracoid tendon was adopted for this experiment because of its similarity to the human supraspinatus tendon. We developed a full-thickness tendon laceration followed by primary suture. The objective of this study was to detect localization of the responsible cells for repair of the tendon. We examined the process using histology and in situ hybridization. Starting at week 1 the peritendon cells of the bursal side proliferated and migrated into the laceration site. At week 6, the tendon stumps were continuous with new connective tissue. High-level expression of procollagen mRNA in the proliferating peritendon cells on the bursal side demonstrates to contribute to the reparative process, which progressed to the joint side. This mode of repair is different from that of the digital flexor tendon.
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Procolágeno/genética , Lesiones del Manguito de los Rotadores , Manguito de los Rotadores/fisiología , Traumatismos de los Tendones/fisiopatología , Cicatrización de Heridas/fisiología , Animales , Pollos , Colorantes , Modelos Animales de Enfermedad , Eosina Amarillenta-(YS) , Expresión Génica/fisiología , Hematoxilina , Hibridación in Situ , Laceraciones/fisiopatología , Laceraciones/cirugía , ARN Mensajero/análisis , Manguito de los Rotadores/cirugía , Suturas , Traumatismos de los Tendones/cirugíaRESUMEN
Pioneer studies have proposed that multiple metabolic abnormalities, such as insulin resistance, increased Na(+)-H(+) exchanger activity and abnormal intracellular calcium homeostasis, are frequently associated with a subset of essential hypertensive patients with low plasma renin activity (PRA). However, it is unclear whether insulin resistance is related to the low renin status in the very early phase of genetical hypertension. Besides, there is controversy on the subject of the in vivo effect of acute hyperinsulinaemia on sodium-related factors. We investigated the relationship between sodium-related parameters and insulin sensitivity, and the effects of euglycaemic hyperinsulinaemia on cyclic guanosine monophosphate (cGMP) and atrial natriuretic peptide (ANP) levels in 17 young, lean, normotensive male subjects, who displayed extreme predispositions for the development of hypertension. PRA was significantly lower in the positive than in the negative family history group (P < 0.05). Insulin sensitivity (M-value) was correlated with PRA before euglycaemic hyperinsulinaemic clamping (r = 0.577, P < 0.05), and was also inversely correlated with fractional excretion of sodium (FE(Na)) before clamping (r = -0.51, P < 0.05). Euglycaemic hyperinsulinaemia significantly decreased PRA (P < 0.0001) and increased cGMP (P < 0.05) and ANP levels (P < 0.01). In conclusion, insulin sensitivity may be partially determined by PRA levels and FE(Na) before clamping in young, lean, normotensive male subjects. Acute euglycaemic hyperinsulinaemia decreases PRA, and increases cGMP and ANP levels from the fasting condition.
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Hipertensión/inducido químicamente , Hipertensión/genética , Resistencia a la Insulina/genética , Sodio/efectos adversos , Adulto , Factor Natriurético Atrial/sangre , GMP Cíclico/sangre , Técnica de Clampeo de la Glucosa , Homeostasis , Humanos , Hiperinsulinismo/inducido químicamente , Hiperinsulinismo/fisiopatología , Masculino , Valor Predictivo de las Pruebas , Renina/metabolismo , Sensibilidad y Especificidad , Sodio/fisiología , DelgadezRESUMEN
Ca2+ influx is one of the main causative events in hypoxic PC12 cell death, because an extracellular Ca2+ chelator, ethylene glycol bis (2-aminoethyl ether)-N,N,N',N'-tetraacetic acid (EGTA) inhibited and Ca2+ ionophore A23187 mimicked the hypoxic cell death. The hypoxic cell death was markedly prevented by a broad spectrum caspase inhibitor, benzyloxycarbonyl-Val-Ala-Asp-fluoromethylketone (z-VAD-FMK) as well as a calpain inhibitor, calpeptin, as assessed by nuclear staining with Hoechst 33258 and lactate dehydrogenase release. The processing of procaspase-3 was inhibited by z-VAD-FMK, but not by calpeptin. In contrast, z-VAD-FMK failed to block the proteolytic cleavage of fodrin-alpha, a preferential substrate for calpain. On the other hand, degradation of actin and fodrin-alpha was prevented by calpeptin but not by z-VAD-FMK. In addition, not only protein kinase C (PKC)-alpha but also PKC-delta were cleaved to generate approximately 46 kDa fragments. The PKC fragmentation was inhibited by calpeptin but not by z-VAD-FMK. These findings suggest that the extracellular Ca2+ influx induced by hypoxic stress activates calpain, resulting in the degradation of cytoskeletal proteins and generation of PKC fragments almost independently of caspase activation. Therefore, calpain may play an important role in hypoxic PC12 cell death.
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Calpaína/metabolismo , Caspasas/metabolismo , Muerte Celular/fisiología , Citoesqueleto/metabolismo , Hipoxia-Isquemia Encefálica/metabolismo , Degeneración Nerviosa/metabolismo , Proteína Quinasa C/metabolismo , Animales , Calcimicina/farmacología , Calcio/metabolismo , Muerte Celular/efectos de los fármacos , Quelantes/farmacología , Inhibidores de Cisteína Proteinasa/farmacología , Citoesqueleto/patología , Dipéptidos/farmacología , Ácido Egtácico/farmacología , Hipoxia-Isquemia Encefálica/patología , Hipoxia-Isquemia Encefálica/fisiopatología , Ionóforos/farmacología , Isoenzimas/efectos de los fármacos , Isoenzimas/metabolismo , Degeneración Nerviosa/patología , Degeneración Nerviosa/fisiopatología , Células PC12/efectos de los fármacos , Células PC12/metabolismo , Células PC12/patología , Péptido Hidrolasas/efectos de los fármacos , Péptido Hidrolasas/metabolismo , Proteína Quinasa C/efectos de los fármacos , Proteína Quinasa C-alfa , Proteína Quinasa C-delta , RatasRESUMEN
We isolated 13 tobacco calmodulin (CaM) genes, NtCaM1-13, and analyzed their expression profile in response to pathogen infection and wounding using specific DNA probes for individual CaM genes and specific antibodies for CaM proteins in groups I (NtCaM1/2), II (NtCaM3/4/5/6/7/8/11/12 and 9/10) and III (NtCaM13), respectively. Synchronous cell death in tobacco mosaic virus (TMV)-infected N-gene-containing tobacco leaves accompanied a predominant accumulation of NtCaM1, 2 and 13 transcripts and NtCaM13-type protein, which is a possible ortholog of soybean defense-involved CaM (SCaM-4), preceding induction of PR-1 and PR-3 defense genes. Accumulation of NtCaM1, 2, 3 and 4 transcripts was induced within 30 min after wounding and NtCaM1-type protein accumulated transiently after wounding. NtCaM13-type protein, which was found at a low level in healthy leaves, decreased instantly after wounding. The treatment with a proteasome inhibitor, lactacystin, enhanced wound-induced accumulation of NtCaM1-type protein and inhibited wound-induced decrease of NtCaM13-type protein, suggesting that proteasome activity is involved in the degradation of these CaMs. Thus, our results indicate that levels of individual CaM proteins are differentially regulated both transcriptionally and post-transcriptionally in tobacco plants that are exposed to stresses such as pathogen-induced hypersensitive cell death and wounding.