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To reveal the impact of cadmium stress on the physiological mechanism of lettuce, simultaneous determination and correlation analyses of chlorophyll content and photosynthetic function were conducted using lettuce seedlings as the research subject. The changes in relative chlorophyll content, rapid chlorophyll fluorescence induction kinetics curve, and related chlorophyll fluorescence parameters of lettuce seedling leaves under cadmium stress were detected and analyzed. Furthermore, a model for estimating relative chlorophyll content was established. The results showed that cadmium stress at 1 mg/kg and 5 mg/kg had a promoting effect on the relative chlorophyll content, while cadmium stress at 10 mg/kg and 20 mg/kg had an inhibitory effect on the relative chlorophyll content. Moreover, with the extension of time, the inhibitory effect became more pronounced. Cadmium stress affects both the donor and acceptor sides of photosystem II in lettuce seedling leaves, damaging the electron transfer chain and reducing energy transfer in the photosynthetic system. It also inhibits water photolysis and decreases electron transfer efficiency, leading to a decline in photosynthesis. However, lettuce seedling leaves can mitigate photosystem II damage caused by cadmium stress through increased thermal dissipation. The model established based on the energy captured by a reaction center for electron transfer can effectively estimate the relative chlorophyll content of leaves. This study demonstrates that chlorophyll fluorescence techniques have great potential in elucidating the physiological mechanism of cadmium stress in lettuce, as well as in achieving synchronized determination and correlation analyses of chlorophyll content and photosynthetic function.
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Cadmio , Lactuca , Complejo de Proteína del Fotosistema II/metabolismo , Fluorescencia , Fotosíntesis , Clorofila , Plantones , Hojas de la Planta/metabolismoRESUMEN
Localised scleroderma predominantly affects the skin with an unknown aetiology. Despite its clinical importance, no comprehensive bibliometric analysis has been conducted to assess the existing research landscape and future prospects for localised scleroderma. The articles related to localised scleroderma were retrieved from the WoSCC database and analysed by VOSviewer 1.6.10.0 (Leiden University, Netherlands), CiteSpace 6.1.R1 (Dreiser University, USA), and HistCite 2.1 (New York, United States). 2049 research papers pertaining to localised scleroderma spanning the years from 1993 to 2022 were extracted from the WoSCC database. The United States exhibited the highest productivity with 644 papers, accounting for 31.43% of the total output, followed by Germany with 206 papers (10.05%) and Italy with 200 papers (9.76%). Regarding academic institutions and journals, the University of Texas System and Dermatology published the most significant number of papers, and Professor Ihn, H emerged as the most prolific contributor among scholars. The top 10 cited references primarily concentrated on the diagnosis and treatment of localised scleroderma. "Phototherapy" and "methotrexate (MTX)" surfaced as the most recent and noteworthy keywords, representing the research hotspots in the domain of localised scleroderma. This bibliometric analysis furnishes valuable insights into the contemporary research landscape of localised scleroderma.
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Esclerodermia Localizada , Humanos , Esclerodermia Localizada/terapia , Piel , Bibliometría , Bases de Datos Factuales , AlemaniaRESUMEN
Although fresh-cut button mushrooms are popular with consumers, quality deterioration presents a significant shelf-life challenge. In this study, fresh-cut button mushrooms were treated with 0.25 g/L l-cysteine (l-Cys) and evaluated in terms of quality, physiology, and transcriptome sequencing. The results indicated that l-Cys application significantly delayed the browning degree of fresh-cut button mushrooms and reduced weight loss. l-Cys treatment reduced the malondialdehyde content, lipoxygenase activity, and reducing sugar levels while enhancing the soluble protein and total phenolic content. Furthermore, l-Cys treatment reduced the O2- generation rate and H2O2 accumulation while enhancing the catalase activity. Moreover, l-Cys improved the superoxide dismutase, glutathione reductase, and phenylalanine ammonia-lyase activities while reducing those of polyphenol oxidase and peroxidase. Additionally, l-Cys treatment increased endogenous H2S production and AbCBS enzyme activity while decreasing AbCSE enzyme activity. Notably, additional treatment with 1 mM propargylglycine significantly reduced the effect of l-Cys. Moreover, transcriptome sequencing analysis indicated that the differentially expressed genes in the l-Cys group were primarily related to the reactive oxygen species metabolism, oxidoreductase process, membrane integrality, and sulfur metabolism. These findings suggested that l-Cys treatment delayed the aging and extended the shelf life of fresh-cut button mushrooms by regulating the active oxygen species metabolism and water loss and stimulating endogenous H2S production.
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Cisteína , Peróxido de Hidrógeno , Cisteína/metabolismo , Peróxido de Hidrógeno/metabolismo , Oxidorreductasas , OxígenoRESUMEN
Selective cancer cell targeting, controlled drug release, easy construction and multiple therapeutic modalities are some of the desirable characteristics of drug delivery systems. We designed and built simple capsule-like molecular imprinted polymer (MIP)-based nanoparticles for targeted and chemo-photothermal synergistic cancer therapy. Using dopamine (DA) as functional monomer, cross-linking agent as well as photo-thermal agent, ZIF-8 (zeoliticimidazolate framework-8) as drug carrier, epitope of EGFR (epidermal growth factor receptor) as template molecules, molecular imprinted polymer (MIP) drug carrier was constructed. The ability of MIP layer to bind to EGFR epitope endowed the MD (DOX@MIP) particles to recognize EGFR-overexpressing cancer cells, while the pH-responsiveness and photothermal conversion ability of PDA (polydopamine) achieved chemo-photothermal synergistic effects upon NIR irradiation. Taken together, the MD nanoparticles integrated cancer cell targeting recognition, intelligent drug release, biocompatibility and chemo-photothermal effects, and is therefore a promising tool for targeted cancer therapy with minimal toxicity to normal cells, as well as tumor imaging.
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Hipertermia Inducida , Nanopartículas , Neoplasias , Doxorrubicina , Sistemas de Liberación de Medicamentos , Liberación de Fármacos , Indoles , Neoplasias/tratamiento farmacológico , Fototerapia , PolímerosRESUMEN
The development and application of new selenium-enriched polysaccharides has become a critical topic in recent years. In this study, a natural selenium-enriched polysaccharide fraction (Se-POP-21) produced by Pleurotus ostreatus was purified, characterized, and investigated the antioxidant and antitumor activities in vitro. The Se-POP-21 was mainly composed of mannose, glucose, galactose and arabinose, with a molar ratio of 18.01:2.40:26.15:7.34, of which molecular weight was 15,888 Da and the selenium content was 5.31 µg/g. Spectral analysis demonstrated that Se-POP-21 represented a non-triple helix pyranopolysaccharide and selenium occurred in the form of C-O-Se and SeO. Molecular size and morphology studies showed that Se-POP-21 exhibited a spherical shape with a particle size distribution between 100 and 200 nm, even though Se-POP-21 aggregates were also found with a size between 500 and 600 nm. In addition, Se-POP-21 showed strong scavenging capacity to DPPH and hydroxyl radical. More, cell experiments showed that Se-POP-21 could reduce viability of A549, SKOV3, HepG2 and MCF-7 cells, induce apoptosis and inhibit metastasis of A549 cells. A potential mechanism was that Se-POP-21 inhibited the epithelial-to-mesenchymal transition of cancer cells. Se-POP-21 featured no significant effect on normal cells. Se-POP-21 showed great potential to develop into a natural antioxidant or low-toxic antitumor drug.
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Pleurotus/enzimología , Polisacáridos/aislamiento & purificación , Selenio/química , Células A549 , Antineoplásicos/farmacología , Antioxidantes/química , Antioxidantes/farmacología , Apoptosis/efectos de los fármacos , Línea Celular Tumoral , Carbohidratos de la Dieta/farmacología , Células Hep G2 , Humanos , Células MCF-7 , Peso Molecular , Pleurotus/química , Pleurotus/metabolismo , Polisacáridos/química , Polisacáridos/metabolismo , Selenio/aislamiento & purificaciónRESUMEN
Selenium-enriched polysaccharides have been gaining great attention for their antitumor activity in recent years. In this study, a novel selenium polysaccharide fraction (Se-POP-3) produced by Pleurotus ostreatus was characterized and its antitumor activity explored at cellular level. Results showed that Se-POP-3 has 25.9 µg/g of selenium, an average molecular weight of 16,106 Da, and is mainly composed of mannose, glucose and galactose with a molar ratio of 1.7:49.6:2.4. Spectra analysis revealed Se-POP-3 as a pyranopolysaccharide linked by α-glycoside bonds in the main chain, and selenium may occur in the form of COSe and SeO. A single sphere of Se-POP-3 has 50-60 nm in aqueous solution, even though it can agglomerate to form larger spherical structures. In vitro experiments with cancer and normal cell lines showed that Se-POP-3 can induce apoptosis and inhibit migration of cancer cells. Potential anticancer mechanism is that Se-POP-3 can disrupt the Bax/Bcl-2 protein ratio and inhibit the epithelial-to-mesenchymal transition (EMT) in cancer cells. Se-POP-3 showed no significant effect on the growth of normal cell lines. Se-POP-3 showed great potential as a broad-spectrum antitumor agent and dietary supplement.
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Neoplasias/tratamiento farmacológico , Pleurotus/química , Polisacáridos/química , Selenio/química , Apoptosis/efectos de los fármacos , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Transición Epitelial-Mesenquimal/efectos de los fármacos , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Humanos , Polisacáridos/farmacología , Proteínas Proto-Oncogénicas c-bcl-2/genética , Selenio/farmacología , Proteína X Asociada a bcl-2/genéticaRESUMEN
Although various factors were reported to be related to post-herpetic neuralgia (PHN), studies based on adequate and comprehensive data were absent. Data was extracted from cases of hospitalized patients with herpes zoster in dermatology department, Sichuan hospital of traditional Chinese medicine range from December, 2011 to February, 2018, and then cleaned to build prediction model with TREENET algorithms. Following evaluated the prediction model by ROC and confusion matrix, variables importance ranking and variables dependency analysis were performed, resulting in the importance ranking of factors for PHN and the dependency between factors and PHN. Based on strict inclusion and exclusion criteria, 1303 (571 PHN and 732 normal controls) cases and 2958 indicators were selected. Model evaluation showed high ROC value (training sample = 0.985, test samples = 0.752) and high accuracy value (70.27%), which indicated that the model was predictive. After variables importance ranking and variables dependency analysis, 62 variables in the model were associated with the occurrence of PHN. Our study identified 62 variables related to PHN and revealed that various variables were the important risk factors for PHN, including age, MCHC, sodium and UA.
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Herpes Zóster , Neuralgia Posherpética , Análisis de Datos , Herpes Zóster/diagnóstico , Herpes Zóster/epidemiología , Hospitales , Humanos , Medicina Tradicional China , Neuralgia Posherpética/diagnóstico , Neuralgia Posherpética/epidemiologíaRESUMEN
BACKGROUND: Coronavirus disease 2019 (COVID-19) is one of the infectious diseases that have seriously threatened global public health since its outbreak in 2019. Due to the complicated Pathogenesis, high infectivity and high fatality rate of COVID-19, there is currently no effective treatment for such epidemic disease. Traditional Chinese medicine has a long clinical history for the prevention and treatment of this kind of acute infectious disease. Qingfei Paidu Decoction (QFPD) is widely used in treating COVID-19 in China. However, there is still a lack of comprehensive and systematic evidence on the effectiveness and safety of Qingfei Paidu Decoction. METHODS: We will search each database from the built-in until May 2020. The English literature mainly searches Cochrane Library, PubMed, EMBASE, and Web of Science, while the Chinese literature comes from CNKI, CBM, VIP, and Wangfang database. Simultaneously we will retrieval clinical registration tests and grey literatures. This study only screen the clinical randomized controlled trials (RCTs) about QFPD for COVID-19 to assess its efficacy and safety. The two researchers worked independently on literature selection, data extraction, and quality assessment. The dichotomous data is represented by relative risk (RR), and the continuous is expressed by mean difference (MD) or standard mean difference (SMD), eventually the data is synthesized using a fixed effect model (FEM) or a random effect model (REM) depending on whether or not heterogeneity exists. Total clinical effective rate, improvement rate of lung CT, adverse events were evaluated as the main outcomes. Effective rate of clinical symptoms, treatment time were secondary outcomes. Finally, meta-analysis was conducted by RevMan software version 5.3. RESULTS: The results of our research will be published in a peer-reviewed journal. CONCLUSION: This systematic review aims to provide new evidence of QFPD for COVID-19 in terms of its efficacy and safety. PROSPERO REGISTRATION NUMBER: CRD42020200894.
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Infecciones por Coronavirus/tratamiento farmacológico , Medicamentos Herbarios Chinos/uso terapéutico , Neumonía Viral/tratamiento farmacológico , Betacoronavirus , COVID-19 , Medicamentos Herbarios Chinos/administración & dosificación , Medicamentos Herbarios Chinos/efectos adversos , Humanos , Pandemias , Ensayos Clínicos Controlados Aleatorios como Asunto , Proyectos de Investigación , SARS-CoV-2 , Tratamiento Farmacológico de COVID-19 , Metaanálisis como AsuntoRESUMEN
OBJECTIVE: To evaluate the effectiveness and safety of acupuncture combined with Madopar for the treatment of Parkinson's disease (PD), compared to the use of Madopar alone. METHODS: A systematic search was carried out for randomised controlled trials (RCTs) of acupuncture and Madopar for the treatment of PD published between April 1995 and April 2015. The primary outcome was total effectiveness rate and secondary outcomes included Unified Parkinson's Disease Rating Scale (UPDRS) scores. Data were pooled and analysed with RevMan 5.3. Results were expressed as relative ratio (RR) with 95% confidence interval (CIs). RESULTS: Finally, 11 RCTs with 831 subjects were included. Meta-analyses showed that acupuncture combined with Madopar for the treatment of PD can significantly improve the clinical effectiveness compared with Madopar alone (RR=1.28, 95% CI 1.18 to 1.38, P<0.001). It was also found that acupuncture combined with Madopar significantly improved the UPDRS II (SMD=-1.00, 95% CI -1.71 to -0.29, P=0.006) and UPDRS I-IV total summed scores (SMD=-1.15, 95% CI -1.63 to -0.67, P<0.001) but not UPDRS I (SMD=-0.37, 95% CI -0.77 to 0.02, P=0.06), UPDRS III (SMD=-0.93, 95% CI -2.28 to 0.41, P=0.17) or UPDRS IV (SMD=-0.78, 95% CI -2.24 to 0.68, P=0.30) scores. Accordingly, acupuncture combined with Madopar appeared to have a positive effect on activities of daily life and the general condition of patients with PD, but was not better than Madopar alone for the treatment of mental activity, behaviour, mood and motor disability. In the safety evaluation, it was found that acupuncture combined with Madopar was associated with significantly fewer adverse effects including gastrointestinal reactions (RR=0.38, 95% CI 0.23 to 0.65, P<0.001), on-off phenomena (RR=0.27, 95% CI 0.11 to 0.66, P=0.004) and mental disorders (RR=0.24, 95% CI 0.06 to 0.92, P=0.04) but did not significantly reduce dyskinesia (RR=0.64, 95% CI 0.35 to 1.16, P=0.14). CONCLUSION: Acupuncture combined with Madopar appears, to some extent, to improve clinical effectiveness and safety in the treatment of PD, compared with Madopar alone. This conclusion must be considered cautiously, given the quality of most of the studies included was low. Therefore, more high-quality, multicentre, prospective, RCTs with large sample sizes are needed to further clarify the effect of acupuncture combined with Madopar for PD.
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Terapia por Acupuntura/mortalidad , Benserazida/uso terapéutico , Dopaminérgicos/uso terapéutico , Levodopa/uso terapéutico , Terapia Combinada , Combinación de Medicamentos , Humanos , Ensayos Clínicos Controlados Aleatorios como Asunto , Resultado del TratamientoRESUMEN
Aims. To establish a logistic regression (LR) prediction model for hepatotoxicity of Chinese herbal medicines (HMs) based on traditional Chinese medicine (TCM) theory and to provide a statistical basis for predicting hepatotoxicity of HMs. Methods. The correlations of hepatotoxic and nonhepatotoxic Chinese HMs with four properties, five flavors, and channel tropism were analyzed with chi-square test for two-way unordered categorical data. LR prediction model was established and the accuracy of the prediction by this model was evaluated. Results. The hepatotoxic and nonhepatotoxic Chinese HMs were related with four properties (p < 0.05), and the coefficient was 0.178 (p < 0.05); also they were related with five flavors (p < 0.05), and the coefficient was 0.145 (p < 0.05); they were not related with channel tropism (p > 0.05). There were totally 12 variables from four properties and five flavors for the LR. Four variables, warm and neutral of the four properties and pungent and salty of five flavors, were selected to establish the LR prediction model, with the cutoff value being 0.204. Conclusions. Warm and neutral of the four properties and pungent and salty of five flavors were the variables to affect the hepatotoxicity. Based on such results, the established LR prediction model had some predictive power for hepatotoxicity of Chinese HMs.
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OBJECTIVE: To observe the effect of tonifying liver and kidney-essence herbs on expression of a nerve regeneration inhibitor, Nogo for neuron A (Nogo-A), and its associated signaling molecule, low-affinity neurotrophin receptor p75 (p75(NTR)), in rats with cerebral ischemic stroke (CIS), with the aim of exploring the possible mechanism of tonifying liver and kidney-essence herbs in recovery following injury to the central nervous system. METHODS: A cerebral ischemic stroke model in SD rats was established with the suture-occlusion method. Successful model rats were divided into placebo and herb groups at random; sham-operated and control groups were set up simultaneously. Each of these groups was divided into six subgroups at random. Expression of Nogo-A and p75(NTR) was evaluated with immunofluorescence microscopy at days 3, and weeks 1, 2, 3, 4 and 8 after administration. RESULTS: Tonifying liver and kidney-essence herbs suppressed the expression of Nogo-A and p75(NTR) (P < 0.05 and P < 0.01, respectively). CONCLUSION: Suppressing the expression of Nogo-A and p75(NTR) is possibly one of the mechanisms underlying the ability of tonifying liver and kidney-essence herbs to promote recovery of the injured central nervous system.
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Medicamentos Herbarios Chinos/administración & dosificación , Proteínas de la Mielina/genética , Receptor de Factor de Crecimiento Nervioso/genética , Accidente Cerebrovascular/tratamiento farmacológico , Animales , Modelos Animales de Enfermedad , Expresión Génica/efectos de los fármacos , Humanos , Masculino , Proteínas de la Mielina/metabolismo , Proteínas Nogo , Ratas , Ratas Sprague-Dawley , Receptor de Factor de Crecimiento Nervioso/metabolismo , Accidente Cerebrovascular/genética , Accidente Cerebrovascular/metabolismoRESUMEN
OBJECTIVES: (1) To investigate whether voice gender discrimination (VGD) could be a useful indicator of the spectral and temporal processing abilities of individual cochlear implant (CI) users; (2) To examine the relationship between VGD and speech recognition with CI when comparable acoustic cues are used for both perception processes. DESIGN: VGD was measured using two talker sets with different inter-gender fundamental frequencies (F(0)), as well as different acoustic CI simulations. Vowel and consonant recognition in quiet and noise were also measured and compared with VGD performance. STUDY SAMPLE: Eleven postlingually deaf CI users. RESULTS: The results showed that (1) mean VGD performance differed for different stimulus sets, (2) VGD and speech recognition performance varied among individual CI users, and (3) individual VGD performance was significantly correlated with speech recognition performance under certain conditions. CONCLUSIONS: VGD measured with selected stimulus sets might be useful for assessing not only pitch-related perception, but also spectral and temporal processing by individual CI users. In addition to improvements in spectral resolution and modulation detection, the improvement in higher modulation frequency discrimination might be particularly important for CI users in noisy environments.
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Implantación Coclear/instrumentación , Implantes Cocleares , Corrección de Deficiencia Auditiva/psicología , Pérdida Auditiva/rehabilitación , Personas con Deficiencia Auditiva/rehabilitación , Discriminación de la Altura Tonal , Acústica del Lenguaje , Percepción del Habla , Calidad de la Voz , Estimulación Acústica , Adulto , Anciano , Audiometría de Tonos Puros , Audiometría del Habla , Umbral Auditivo , Señales (Psicología) , Discriminación en Psicología , Femenino , Pérdida Auditiva/psicología , Humanos , Masculino , Persona de Mediana Edad , Ruido/efectos adversos , Enmascaramiento Perceptual , Personas con Deficiencia Auditiva/psicología , Reconocimiento en Psicología , Factores Sexuales , Factores de TiempoRESUMEN
The present study used eight normal-hearing (NH) subjects, listening to acoustic cochlear implant (CI) simulations, to examine the effects of spectral shifting on speech recognition in noise. Speech recognition was measured using spectrally matched and shifted speech (vowels, consonants, and IEEE sentences), generated by 8-channel, sine-wave vocoder. Measurements were made in quiet and in noise (speech-shaped static noise and speech-babble at 5 dB signal-to-noise ratio). One spectral match condition and four spectral shift conditions were investigated: 2 mm, 3 mm, and 4 mm linear shift, and 3 mm shift with compression, in terms of cochlear distance. Results showed that speech recognition scores dropped because of noise and spectral shifting, and that the interactive effects of spectral shifting and background conditions depended on the degree/type of spectral shift, background conditions, and the speech test materials. There was no significant interaction between spectral shifting and two noise conditions for all speech test materials. However, significant interactions between linear spectral shifts and all background conditions were found in sentence recognition; significant interactions between spectral shift types and all background conditions were found in vowel recognition. Overall, the results suggest that tonotopic mismatch may affect performance of CI users in complex listening environments.
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Vías Auditivas/fisiología , Ruido/efectos adversos , Enmascaramiento Perceptual , Reconocimiento en Psicología , Inteligibilidad del Habla , Percepción del Habla , Estimulación Acústica , Adulto , Audiometría de Tonos Puros , Audiometría del Habla , Umbral Auditivo , Implantes Cocleares , Femenino , Humanos , Masculino , Procesamiento de Señales Asistido por Computador , Acústica del Lenguaje , Adulto JovenRESUMEN
OBJECTIVES: Cochlear implant listeners are able to at least partially adapt to the spectral mismatch associated with the implant device and speech processor via daily exposure and/or explicit training. The overall goal of this study was to investigate interactions between short-term unsupervised learning (i.e., passive adaptation) and the degree of spectral mismatch in normal-hearing listeners' adaptation to spectrally shifted vowels. DESIGN: Normal-hearing subjects were tested while listening to acoustic cochlear implant simulations. Unsupervised learning was measured by testing vowel recognition repeatedly over a 5 day period; no feedback or explicit training was provided. In experiment 1, subjects listened to 8-channel, sine-wave vocoded speech. The spectral envelope was compressed to simulate a 16 mm cochlear implant electrode array. The analysis bands were fixed and the compressed spectral envelope was linearly shifted toward the base by 3.6, 6, or 8.3 mm to simulate different insertion depths of the electrode array, resulting in a slight, moderate, or severe spectral shift. In experiment 2, half the subjects were exclusively exposed to a severe shift with 8 or 16 channels (exclusive groups), and half the subjects were exposed to 8-channel severely shifted speech, 16-channel severely shifted speech, and 8-channel moderately shifted speech, alternately presented within each test session (mixed group). The region of stimulation in the cochlea was fixed (16 mm in extent and 15 mm from the apex) and the analysis bands were manipulated to create the spectral shift conditions. To determine whether increased spectral resolution would improve adaptation, subjects were exposed to 8- or 16-channel severely shifted speech. RESULTS: In experiment 1, at the end of the adaptation period, there was no significant difference between 8-channel speech that was spectrally matched and that shifted by 3.6 mm. There was a significant, but less-complete, adaptation to the 6 mm shift and no adaptation to the 8.3 mm shift. In experiment 2, for the mixed exposure group, there was significant adaptation to severely shifted speech with 8 channels and even greater adaptation with 16 channels. For the exclusive exposure group, there was no significant adaptation to severely shifted speech with either 8 or 16 channels. CONCLUSIONS: These findings suggest that listeners are able to passively adapt to spectral shifts up to 6 mm. For spectral shifts beyond 6 mm, some passive adaptation was observed with mixed exposure to a smaller spectral shift, even at the expense of some low frequency information. Mixed exposure to the smaller shift may have enhanced listeners' access to spectral envelope details that were not accessible when listening exclusively to severely shifted speech. The results suggest that the range of spectral mismatch that can support passive adaptation may be larger than previously reported. Some amount of passive adaptation may be possible with severely shifted speech by exposing listeners to a relatively small mismatch in conjunction with the severe mismatch.