Guessability of Indian picture symbols for communication (IPSC) and picture communication symbols (PCS) among Malayalam-speaking typical adults.

The purpose of this study was to investigate the perceived symbol referent relationship for selected symbols in typical adults for two different symbol sets: Indian Picture Symbols for Communication (IPSC) and Picture Communication Symbols (PCS) to identify cultural influences on symbol recognition. A total of 240 typical adults, including 120 nonprofessionals, and 120 health professionals, from Kerala, a southern state in India, participated in the study. A guessability task involving IPSC and PCS symbols for 30 target referents was utilized. Guessability scores for each participant as well as each symbol stimuli across two symbol sets were determined. The guessability scores for IPSC were significantly (p <.001) higher than PCS. For both symbol sets, nouns were the most accurately guessed, followed by verbs, adjectives, and prepositions. The results also revealed that prompting and previous exposure to symbols tend to influence the transparency of symbols. Error analyses revealed that visual and conceptual cues within a symbol tend to influence guessability. The results indicate that cultural and linguistic factors play a role in symbol guessability. The study highlights the importance of investigating the iconicity of IPSC and PCS symbols across different populations within India, before using symbols for educational/clinical purposes.

Comparing verbal and aided single sentence productions in Malayalam-speaking adults with aphasia: a preliminary investigation.

The primary aim of the study was to investigate the semantic and syntactic aspects of verbal and aided single sentence productions in adults with aphasia and neurotypical adults to determine which mode allowed the exchange of information more effectively. The participants of this study included 20 adults with aphasia and 20 neurotypical adults who were native speakers of Malayalam, an Indo-Dravidian language spoken in the south-western state of Kerala in India. Thirteen action picture stimuli were constructed to elicit single sentences. The participants were expected to describe the action picture in a single sentence using spoken language as well as using Picture Communication Symbols (PCS). The semantic aspect of each sentence produced was analysed using Correct Information Unit (CIU) analyses, and the syntactic aspects were measured using (i) percentage of grammatically complete sentences, (ii) percentage of the correct number of verbs, and (iii) total number of syntactic errors. A sentence production accuracy scale was constructed to obtain a combined score for semantic and syntactic aspects of each sentence produced. The results suggested that while both verbal and aided modes were effectively used for the exchange of information by neurotypical adults and adults with anomic aphasia, the aided mode was used more effectively by adults with Broca's aphasia. To conclude, the study highlights the importance of (a) using visual symbols even for those with mild aphasia as it tends to improve phonological and articulatory abilities, (b) use of symbols to construct simple sentences to communicate in adults with severe aphasia, (c) evaluation of the ability to use alternate modes of communication and also the preferred mode of communication in adults with aphasia.

Capacity & capability building for applied dementia research in low- & middle-income countries: Two exemplars from South Asia.

BACKGROUND & OBJECTIVES: Cognitive and other neurodegenerative conditions related to ageing have become public health priorities in low- and middle-income countries. However, contextually based, applied research to support the development of awareness, diagnosis and care pathways for people with dementia in South Asia is still largely undeveloped. This study was aimed to use applied research studies for dementia in South Asia as exemplars of how individual-level capacity and capability building for dementia research can be achieved. METHODS: Using Theory of Change as a framework, we embedded capacity and capability building into the studies through six domains: people (human resources), research integrity and governance, study delivery skills, international collaborative working, patient and public involvement (PPI) (awareness raising, stigma and health literacy) and development of 'pathways'. For each aspect, development goals were defined and how they would be achieved. RESULTS: New principal investigators, research assistants (including outcome raters), study coordinators and intervention practitioners were trained across eight study sites in India, Pakistan, and Bangladesh, for dementia research. Training was delivered at study start, and through booster sessions, using workshops, face-to-face sessions, online training and video-link sessions. International collaborations were fostered, leading to a proposal for international funding. Each study site co-created PPI events to raise awareness and to inform the research. The recruitment pathways and study logistics fostered the development dementia diagnosis and care pathways. INTERPRETATION & CONCLUSIONS: Embedding capacity and capability building in applied dementia research in South Asia fosters the sustainability of dementia research, which is essential in developing diagnostic and care pathways.

A Systematic Review of the Influence of Bolus Characteristics on Respiratory Measures in Healthy Swallowing.

There have been a number of studies on the effect of bolus volume, consistency, texture, temperature and taste on the oropharyngeal swallowing physiology. However, its influence on the respiratory function associated with swallow is not well understood. This study aimed at systematically analysing and documenting the prevailing research literature on respiratory functions before, during, and after healthy swallows of boluses with varied characteristics. The PRISMA guidelines were followed for retrieval of relevant research. From among the 48,329 reports screened for inclusion criteria, 25 articles were included for data extraction. Each of these reports was evaluated for its design, methodology and reporting quality and also the level of evidence provided by them. The results revealed that the scientific evidence in this regard was restricted to level II. Majority of the studies included considered bolus volume as the variable than bolus consistency, taste or temperature. Expiratory phase was preferred surrounding the apnea irrespective of volume, consistency or taste but changed with temperature variations across age groups. The reports are equivocal on the duration of respiratory apnea, and length of respiratory cycles before and after the apnea. The temporal coordination of pharyngeal swallow events was found to be independent of bolus volume. This review concluded that bolus characteristics have differential effects on the respiratory functions during swallow beyond a 'central sensory threshold' level. Objective standardization of bolus characteristics may be the immediate requirement for generalization of future research findings in this direction.

Design, synthesis and molecular docking of pyrazolo [3,4d] thiazole hybrids as potential anti-HIV-1 NNRT inhibitors.

A series of pyrazolo[3.4,d]thiazole hybrids 6 were synthesized from 5-arylidene-2-imino-3-(4-arylthiazol-2-yl)-thiazolidin-4-ones 5. The 5-arylidene-2-imino-3-(4-arylthiazol-2-yl)-thiazolidin-4-ones 5 were synthesized from 2-amino-4-arylthiazoles 1 and 2-chloro-acetamido-4-arylthiazoles 2 via the formation of 2-imino-3-(4-substituted-arylthiazol-2-yl)-thiazolidin-4-ones 3 using substituted aldehydes 4. The 5-acrylidene derivative 5 on cyclisation with phenyl hydrazine give the pyrazolo [3, 4, d] thiazole derivatives 6. The obtained pyrazolo [3.4, d]thiazole derivatives were studied as anti-HIV-1 NNRT inhibitors. It was found that these compounds might have potent RT inhibition activity.

Current-Phase Relation of Ballistic Graphene Josephson Junctions.

The current-phase relation (CPR) of a Josephson junction (JJ) determines how the supercurrent evolves with the superconducting phase difference across the junction. Knowledge of the CPR is essential in order to understand the response of a JJ to various external parameters. Despite the rising interest in ultraclean encapsulated graphene JJs, the CPR of such junctions remains unknown. Here, we use a fully gate-tunable graphene superconducting quantum intereference device (SQUID) to determine the CPR of ballistic graphene JJs. Each of the two JJs in the SQUID is made with graphene encapsulated in hexagonal boron nitride. By independently controlling the critical current of the JJs, we can operate the SQUID either in a symmetric or asymmetric configuration. The highly asymmetric SQUID allows us to phase-bias one of the JJs and thereby directly obtain its CPR. The CPR is found to be skewed, deviating significantly from a sinusoidal form. The skewness can be tuned with the gate voltage and oscillates in antiphase with Fabry-Pérot resistance oscillations of the ballistic graphene cavity. We compare our experiments with tight-binding calculations that include realistic graphene-superconductor interfaces and find a good qualitative agreement.

Side Gate Tunable Josephson Junctions at the LaAlO3/SrTiO3 Interface.

Novel physical phenomena arising at the interface of complex oxide heterostructures offer exciting opportunities for the development of future electronic devices. Using the prototypical LaAlO3/SrTiO3 interface as a model system, we employ a single-step lithographic process to realize gate-tunable Josephson junctions through a combination of lateral confinement and local side gating. The action of the side gates is found to be comparable to that of a local back gate, constituting a robust and efficient way to control the properties of the interface at the nanoscale. We demonstrate that the side gates enable reliable tuning of both the normal-state resistance and the critical (Josephson) current of the constrictions. The conductance and Josephson current show mesoscopic fluctuations as a function of the applied side gate voltage, and the analysis of their amplitude enables the extraction of the phase coherence and thermal lengths. Finally, we realize a superconducting quantum interference device in which the critical currents of each of the constriction-type Josephson junctions can be controlled independently via the side gates.

Community Health Centre-Based Outreach Clinic for undergraduate dental education: Experience in Helsinki over 8 years.

INTRODUCTION: The University Dental Clinic of the City of Helsinki (UDC) developed a Community Health Centre-Based Outreach Clinic, with emphasis on paediatric dentistry. This study aimed to summarise the experiences and explore the student perspectives of the health centre-based outreach teaching clinic. METHODS: The study data were from the years 2010 to 2016. The dental procedures carried out by the third- to fifth-year dental students were based on electronic health record of patients. The students' self-perceived benefits and free-text comments on the outreach training were collected as part of a yearly questionnaire survey. RESULTS: A vast majority of the paediatric dental procedures that are required for competencies of dental students were performed in the outreach clinic. The most common procedures were fillings with local anaesthesia followed by preventive procedures. The majority of the students were very motivated to participate in the outreach training and reported that it was a useful educational approach to broaden their understanding of oral diseases and clinical experience. CONCLUSION: The outreach clinic gives dental students a chance to gain valuable clinical experience through the number and diversity of the dental procedures they carry out. They gain confidence and get an opportunity to get acquainted with the primary healthcare system and social determinants of oral diseases. Outreach appears to provide complementary clinical experiences that fulfil learning outcomes. Learning objectives should be taken into account when planning the outreach programme in order to offer meaningful and motivating education.

Pectoral nerve block1 versus modified pectoral nerve block2 for postoperative pain relief in patients undergoing modified radical mastectomy: a randomized clinical trial.

BACKGROUND: Pectoral nerve block1 (PEC1) given between pectoralis major and minor, and modified pectoral nerve block2 (mPEC2) performed between pectoralis minor and serratus anterior, can provide continuous analgesia after modified radical mastectomy (MRM) when catheters are placed before skin closure. This study was designed to compare PEC1 and mPEC2 block for providing postoperative pain relief after MRM. METHODS: Sixty-two physically fit patients undergoing MRM were assigned into two groups (Group PEC1, n=31 and Group mPEC2, n=31). Before wound closure, epidural catheter was placed in the group designated muscle plane and 30ml of 0.25% bupivacaine was injected through the catheter after wound closure. Bupivacaine 15ml of 0.25% top up was given on patient's demand or whenever visual analogue scale (VAS) score was>4. Time for first analgesia (TFA), number of top ups and VAS was recorded at 0.5, 6, 12, 18, 24 h after surgery. Sensory blockade was assessed 30 min after extubation. RESULTS: Analgesia was significantly prolonged in group mPEC2 [mean(SD)] 313.45(43.05) vs 258.87(34.71) min in group PEC1, P<0.001. Total pain experienced over 24 h was significantly less in group mPEC2 [mean(SD)] 9.77(6.93) than in group PEC1 24.19(10.81), P<0.0001. Consequently, top up requirements were significantly reduced in group mPEC2 than in group PEC1 [median(range)] 3(2-4) vs 4(3-5) respectively, P<0.001. Lateral pectoral (77.42% and 35.48%) and thoracodorsal nerves (93.55% and 48.39%) had higher incidence of sensory block in group mPEC2 than group PEC1, P<0.001. CONCLUSIONS: mPEC2 provides better postoperative analgesia than PEC1 when catheters are placed under direct vision after MRM. CLINICAL TRIAL REGISTRATION: CTRI/2017/02/007811 (REF/2015/11/010185).

Volatile organic compounds and good laboratory practices in the in vitro fertilization laboratory: the important parameters for successful outcome in extended culture.

PURPOSE: This study aims to describe the role of implementing good laboratory practices to improve in vitro fertilization (IVF) outcomes which are of great interest for practitioners dealing with infertility. METHODS: Certain modifications were introduced in May 2015 in our IVF laboratory like high-efficiency particulate air CODA system, steel furniture instead of wooden, use of new disinfectants like oosafe, and restriction of personnel entry along with avoidance of cosmetics like perfume to improve pregnancy rates. Volatile organic compound (VOC) meter reading was monitored at two time points and five different places in the laboratory to compare the embryonic development parameters before (group A: July 2014-April 2015) and after (group B: July 2015-April 2016) remodeling. RESULTS: The IVF outcomes from 1036 cycles were associated in this study. Reduction in VOC meter readings, enhanced air quality, improvement in blastocyst formation rate, implantation, and clinical pregnancy rate were observed in the laboratory after implementation of new facilities. Results illustrated that the attention must be focused on potential hazards which expose laboratories to elevated VOC levels. Blastocyst formation rate increased around 18%. Implantation rate, clinical pregnancy rate, and live birth rate increased by around 11, 10, and 8%, respectively. CONCLUSION: In conclusion, with proper engineering and material selection, we have been able to reduce chemical contamination and adverse effects on culture with optimized IVF results. SUPPORT: None.

Optimized weak measurements of Goos-Hänchen and Imbert-Fedorov shifts in partial reflection.

The spatial and the angular variants of the Imbert-Federov (IF) beam shifts and the angular Goos-Hänchen (GH) shift contribute in a complex interrelated way to the resultant beam shift in partial reflection at planar dielectric interfaces. Here, we show that the two variants of the IF effects can be decoupled and separately observed by weak value amplification and subsequent conversion of spatial ↔angular nature of the beam shifts using appropriate pre and post selection of polarization states. Such optimized weak measurement schemes also enable one to nullify one effect (either the GH or the IF) and exclusively observe the other. We experimentally demonstrate this and illustrate various other intriguing manifestations of optimized weak measurements in elliptical and / or linear polarization basis. We also present a Poincare sphere based analysis on conversion / retention of the angular or spatial nature of the shifts with pre and post selection of states in weak measurement. The demonstrated ability to amplify, controllably decouple or combine the beam shifts via weak measurements may prove to be valuable for understanding the different physical contributions of the effects and for their applications in sensing and precision metrology.

Simultaneous weak value amplification of angular Goos-Hänchen and Imbert-Fedorov shifts in partial reflection.

The optical analogue of quantum weak measurements has shown considerable promise for the amplification and observation of tiny optical beam shifts, namely Goos-Hänchen (GH) and Imbert-Fedorov (IF) shifts. Here, we demonstrate simultaneous weak value amplification of both the angular GH and the IF shifts in partial reflection of a fundamental Gaussian beam at planar dielectric interfaces. We employ pre and postselection schemes with appropriate linear polarization basis states for simultaneous weak measurements and amplification of both of these shifts. The experimentally observed enhancement of the beam shifts and their dependence on the angle of incidence are analyzed/interpreted via theoretical treatment of weak measurements.

Melatonin improves ultraviolet B-induced oxidative damage and inflammatory conditions in cutaneous tissue of a diurnal Indian palm squirrel Funambulus pennanti.

BACKGROUND: Skin is exposed to various abiotic and biotic factors. Solar radiation, of which ultraviolet (UV) rays are a principle component, increases the free radical load, and the accumulation of reactive oxygen species (ROS) causes lipid peroxidation, DNA damage and apoptosis, and is also associated with inflammatory responses recruiting molecules [nuclear factor (NF)-κB, interleukin (IL)-6] that can potentially further aggravate the damaged milieu of the cells. One of the potent causes of skin cancers is exposure to UV rays. UV radiation generates a wide range of biological responses such as adaptive, inflammatory and immunological reactions in the skin. OBJECTIVE: To examine the effects of pretreatment with melatonin on UVB (290-320 nm) radiation-mediated damage to the skin of a diurnal rodent Funambulus pennanti. RESULTS: The UVB radiation (1·5 J cm(-2) for 30 min daily on the shaved abdominal area) for 4 days caused a significant increase in the lipid peroxidation products (thiobarbituric acid reactive substances, TBARS) and decreased the activity of the antioxidant enzymes (superoxide dismutase, catalase and glutathione peroxidase) of the skin. Pretreatment with melatonin (100 µg 100 g(-1) bodyweight subcutaneously) improved the damage induced by UVB radiation on the skin and might act via a receptor-independent mechanism. No significant effect of melatonin pretreatment was found on the expression pattern of MT1 (melatonin membrane receptor) and RORα (nuclear retinoic orphan receptor alpha), which suggests a receptor-independent action. However, NF-κB and inflammatory cytokine IL-6 levels were downregulated in the squirrels pretreated with melatonin before the UVB radiation. CONCLUSION: UVB radiation induced oxidative stress in the skin culminating in an inflammatory response. The action of melatonin in protecting the skin from oxidative damage occurs in a receptor-independent manner by lowering the oxidative damage and inflammatory response. On the other hand, melatonin decreased the expression of NF-κB and the circulating proinflammatory cytokine IL-6, suggesting an anti-inflammatory action in protecting the skin from UVB radiation.

Association between angiotensin converting enzyme gene insertion/deletion polymorphism and intracerebral haemorrhage in North Indian population: a case control study and meta-analysis.

The purpose of this study was to determine the relationship between Angiotensin converting enzyme (ACE) insertion/deletion polymorphism and ICH with an ACE level in a North Indian population. Patient with ICH and age- and sex- matched control subjects were recruited. Case control study design was used. Genotyping was performed by using Polymerase chain reaction. Serum ACE levels were measured by colorimetric method. Our results were integrated with other reported studies across different countries in a meta-analysis. One hundred and six patients with ICH and 106 age- and sex- matched control subjects were recruited. Mean age of cases and control subjects were 53.4 ± 1 and 52.9 ± 13.4, respectively. The DD genotypes were more frequency distributed in cases compared with controls (OR 2; 95 % CI, 1.02-3.8, P = 0.04) under a recessive model of inheritance. Meta-analysis suggests significant association between ACE I/D polymorphism and risk of ICH (OR 1.98; 95 % CI, 1.53-2.57) under the recessive model of inheritance and under the dominant model of inheritance (OR 1.31; 95 % CI, 1.18-1.45). The findings of the present study show a significant association between ACE insertion/deletion polymorphism and ICH. Meta-analysis indicate that ACE I/D polymorphism may be a susceptible marker for risk factor of ICH in Asian population.

Characterization of oocyte-expressed GDF9 gene in buffalo and mapping of its TSS and putative regulatory elements.

Summary In spite of emerging evidence about the vital role of GDF9 in determination of oocyte competence, there is insufficient information about its regulation of oocyte-specific expression, particularly in livestock animals. Because of the distinct prominence of buffalo as a dairy animal, the present study was undertaken to isolate and characterize GDF9 cDNA using orthologous primers based on the bovine GDF9 sequence. GDF9 transcripts were found to be expressed in oocytes irrespective of their follicular origin, and shared a single transcription start site (TSS) at -57 base pairs (bp) upstream of ATG. Assignment of the TSS is consistent with the presence of a TATA element at -23 of the TSS mapped in this study. Localization of a buffalo-specific minimal promoter within 320 bp upstream of ATG was consolidated by identification of an E-box element at -113bp. Presence of putative transcription factor binding sites and other cis regulatory elements were analyzed at ~5 kb upstream of TSS. Various germ cell-specific cis-acting regulatory elements (BNCF, BRNF, NR2F, SORY, Foxh1, OCT1, LHXF etc.) have been identified in the 5' flanking region of the buffalo GDF9 gene, including NOBOX DNA binding elements and consensuses E-boxes (CANNTG). Presence of two conserved E-boxes found on buffalo sequence at -520 and -718 positions deserves attention in view of its sequence deviation from other species. Two NOBOX binding elements (NBE) were detected at the -3471 and -203 positions. The fall of the NBE within the putative minimal promoter territory of buffalo GDF9 and its unique non-core binding sequence could have a possible role in the control of the core promoter activity.

Kinetics of GDF9 expression in buffalo oocytes during in vitro maturation and their associated development ability.

The capacity of fully grown oocytes to regulate their own microenvironment by secreted paracrine factors contribute to their developmental competence. In spite of growing evidence about the vital role of Growth Differentiation Factor 9 (GDF9) in determination of oocyte developmental competence, there is insufficient information about time dependent behavior of its expression during in vitro maturation (IVM) to have definite understanding about at what time point during IVM it plays most crucial role. The study reports the kinetics of GDF9 expression under four different IVM supplement conditions in buffalo oocytes and their concomitant development rate up to blastocyst. Oocytes matured under an ideal media condition with all supplements and those cultured with only FSH resulted in significantly higher cumulus expansion, nuclear maturation, cleavage and blastocyst rates. GDF9 expression at both mRNA and protein levels at different time points of IVM revealed that magnitude of mRNA abundance at 8h of IVM was most important towards imparting development competence to buffalo oocytes. Appearance of GDF9 protein in maturing oocytes was found asynchronous with mRNA appearance in the time course of IVM suggesting possible posttranscriptional regulation of this gene under dynamic oocyte cumulus cell communication process. Abundance of mature GDF9 protein at 16 h was most consistently related with all oocyte development parameters.

Improving accuracy of genomic predictions within and between dairy cattle breeds with imputed high-density single nucleotide polymorphism panels.

Achieving accurate genomic estimated breeding values for dairy cattle requires a very large reference population of genotyped and phenotyped individuals. Assembling such reference populations has been achieved for breeds such as Holstein, but is challenging for breeds with fewer individuals. An alternative is to use a multi-breed reference population, such that smaller breeds gain some advantage in accuracy of genomic estimated breeding values (GEBV) from information from larger breeds. However, this requires that marker-quantitative trait loci associations persist across breeds. Here, we assessed the gain in accuracy of GEBV in Jersey cattle as a result of using a combined Holstein and Jersey reference population, with either 39,745 or 624,213 single nucleotide polymorphism (SNP) markers. The surrogate used for accuracy was the correlation of GEBV with daughter trait deviations in a validation population. Two methods were used to predict breeding values, either a genomic BLUP (GBLUP_mod), or a new method, BayesR, which used a mixture of normal distributions as the prior for SNP effects, including one distribution that set SNP effects to zero. The GBLUP_mod method scaled both the genomic relationship matrix and the additive relationship matrix to a base at the time the breeds diverged, and regressed the genomic relationship matrix to account for sampling errors in estimating relationship coefficients due to a finite number of markers, before combining the 2 matrices. Although these modifications did result in less biased breeding values for Jerseys compared with an unmodified genomic relationship matrix, BayesR gave the highest accuracies of GEBV for the 3 traits investigated (milk yield, fat yield, and protein yield), with an average increase in accuracy compared with GBLUP_mod across the 3 traits of 0.05 for both Jerseys and Holsteins. The advantage was limited for either Jerseys or Holsteins in using 624,213 SNP rather than 39,745 SNP (0.01 for Holsteins and 0.03 for Jerseys, averaged across traits). Even this limited and nonsignificant advantage was only observed when BayesR was used. An alternative panel, which extracted the SNP in the transcribed part of the bovine genome from the 624,213 SNP panel (to give 58,532 SNP), performed better, with an increase in accuracy of 0.03 for Jerseys across traits. This panel captures much of the increased genomic content of the 624,213 SNP panel, with the advantage of a greatly reduced number of SNP effects to estimate. Taken together, using this panel, a combined breed reference and using BayesR rather than GBLUP_mod increased the accuracy of GEBV in Jerseys from 0.43 to 0.52, averaged across the 3 traits.

Effect of varying glucose concentrations during in vitro maturation and embryo culture on efficiency of in vitro embryo production in buffalo.

This study was aimed to optimize glucose level at different stages of buffalo in vitro embryo production procedure. Three glucose levels (1.5, 5.6 and 10 mm) along with a control (0 mm) were used at three phases of in vitro fertilisation (IVF) procedure viz. in vitro maturation (IVM), in vitro culture (IVC-I) (12-72 hpi) and IVC-II (72 hpi to 7 dpi). Maturation rate of oocytes was found different under different glucose concentrations, and significantly more number of oocytes reached to MII under 5.6 mm glucose. The glucose levels at each phase (IVM, IVC-I and IVC-II) individually had significant effect on blastocyst rate, and the level used at one phase had significant effect on the outcome of next phase. Complete withdrawal of glucose from any of these stages irrespective of concentrations used at subsequent stage/s resulted in significantly lower number of blastocysts. However, the changing levels of glucose had differential effects during different phases of IVF steps. The most prominent effect of glucose level was observed during IVM. The presence of 5.6 mm glucose at all stages was most effective to yield highest blastocyst rate in buffalo IVF system.

Response to oyster mushroom (Pleurotus ostreatus) extract by sensitized and nonsensitized guinea pig trachea.

Occupational exposure to oyster mushroom (Pleurotus ostreatus) has been associated with obstructive lung disease. Previously, we studied an extract of oyster mushroom (OME) and determined that it causes dose-dependent contractions of nonsensitized guinea pig trachea (GPT). We extend these studies to the investigation of sensitized tissue. In the present study 24 animals were sensitized using ovalbumin (OA) and subsequently challenged with an aerosol of 2.5% OA. A control group of 12 nonsensitized GPs was also studied. Tracheas were removed and were divided into rings in which the epithelium was retained (EP+) or removed (EP-). Dose-related contractions of sensitized and nonsensitized GPTs were elicited with OME. In nonsensitized animals the EP+ GPTs demonstrated a significantly greater response to OME (100-1000 µl) than did the EP- GPTs (p < 0.01). By contrast, in sensitized GPTs with and without epithelium there was no difference to challenge with OME. Finally, sensitized GPTs with and without epithelium and nonsensitized GPTs with epithelium responded similarly to challenge with OME. These findings suggest that in nonsensitized animals there is an enhancement of contractile response to OME which is in part mediated by the GPT epithelium. In sensitized animals with or without epithelium, the level of bronchoconstrictor response is similar to that of the nonsensitized animals with epithelium, suggesting an enhanced constrictor response independent of epithelium in the sensitized animals.