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2.
Plast Reconstr Surg ; 2024 Apr 23.
Article En | MEDLINE | ID: mdl-38652817

BACKGROUND: Partial-thickness skin wounds are some of the most painful injuries due to large areas of exposed nerve endings. These injuries often require systemic opioid treatments to manage pain adequately. However, in 2021 alone, the CDC reported nearly 17,000 prescription opioid-related deaths in the USA, highlighting the ongoing need for non-opioid treatment strategies. In this manuscript, we developed a novel single-application ropivacaine-eluting primary wound dressing that could provide sustained ropivacaine delivery to partial-thickness wounds and assessed its in vivo feasibility for prolonged non-opioid analgesia. METHODS: Sustained release of ropivacaine from a poly(lactide-co-e-caprolactone) matrix was first optimized in vitro using dissolution testing and a Box Behnken design of experiments. The optimized dressing was then tested against a clinical control silicone dressing in a porcine partial-thickness wound study to assess analgesic effect, pharmacokinetics, and wound healing. RESULTS: The ropivacaine-eluting dressing showed a moderate analgesic effect in vivo, where normalized single pinprick scores significantly improved pain over the testing period (4-168h) (control vs treatment: 232±25% vs 145±16%, p<0.0003). Ropivacaine blood plasma levels peaked at 8 hours post-treatment, with a maximum concentration of 246 ± 74 ng/mL. No significant differences in wound healing were found when compared to control. CONCLUSION: The ropivacaine-loaded poly(lactide-co-e-caprolactone)-based wound dressing provided sustained delivery of ropivacaine to partial-thickness skin wounds and enhanced analgesic effect compared to a clinical standard control dressing.

3.
Vet Ophthalmol ; 2024 Apr 25.
Article En | MEDLINE | ID: mdl-38662616

OBJECTIVE: To report the corneal clarity outcome following lamellar keratectomy of arcus lipoides corneae secondary to canine hypothyroidism and report a unique retinal manifestation of systemic disease. ANIMAL STUDIED: Four-year-old spayed female Sheepdog-Poodle canine. PROCEDURE: Lamellar keratectomy OD. RESULTS: Bilateral severe arcus lipoides corneae was noted in the initial presentation. Bilateral, symmetric, and multifocal bullous retinal detachments were observed at subsequent visits. Biochemical testing revealed hyperlipidemia presumed to be associated with primary acquired thyroiditis. Corneal clarity and visual behaviors were significantly improved following unilateral lamellar keratectomy with no evidence of recurrence within the year following surgery. Bilateral retinal detachments and hyperlipidemia resolved months after initiation of thyroxine supplementation. Corneal lipidosis in the untreated eye remained static. CONCLUSIONS: Lamellar keratectomy is a viable surgical option for the treatment of arcus lipoides corneae. Hypothyroidism should be considered a differential diagnosis for spontaneous, bilateral, multifocal, and serous retinal detachments.

4.
Science ; 384(6691): 66-73, 2024 Apr 05.
Article En | MEDLINE | ID: mdl-38574138

Asthma is deemed an inflammatory disease, yet the defining diagnostic feature is mechanical bronchoconstriction. We previously discovered a conserved process called cell extrusion that drives homeostatic epithelial cell death when cells become too crowded. In this work, we show that the pathological crowding of a bronchoconstrictive attack causes so much epithelial cell extrusion that it damages the airways, resulting in inflammation and mucus secretion in both mice and humans. Although relaxing the airways with the rescue treatment albuterol did not affect these responses, inhibiting live cell extrusion signaling during bronchoconstriction prevented all these features. Our findings show that bronchoconstriction causes epithelial damage and inflammation by excess crowding-induced cell extrusion and suggest that blocking epithelial extrusion, instead of the ensuing downstream inflammation, could prevent the feed-forward asthma inflammatory cycle.


Asthma , Bronchi , Bronchoconstriction , Animals , Humans , Mice , Asthma/pathology , Asthma/physiopathology , Bronchoconstriction/drug effects , Inflammation/pathology , Signal Transduction , Ion Channels/antagonists & inhibitors , Lysophospholipids/antagonists & inhibitors , Sphingosine/analogs & derivatives , Sphingosine/antagonists & inhibitors , Bronchi/pathology , Bronchi/physiopathology
6.
Immunohorizons ; 8(2): 172-181, 2024 Feb 01.
Article En | MEDLINE | ID: mdl-38353996

Aryl hydrocarbon receptor (AhR) responds to endogenous and exogenous ligands as a cytosolic receptor, transcription factor, and E3 ubiquitin ligase. Several studies support an anti-inflammatory effect of AhR activation. However, exposure to the AhR agonist 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) during early stages of development results in an autoimmune phenotype and exacerbates lupus. The effects of TCDD on lupus in adults with pre-existing autoimmunity have not been described. We present novel evidence that AhR stimulation by TCDD alters T cell responses but fails to impact lupus-like disease using an adult mouse model. Interestingly, AhR antagonist CH223191 also changed T cell balance in our model. We next developed a conceptual framework for identifying cellular and molecular factors that contribute to physiological outcomes in lupus and created models that describe cytokine dynamics that were fed into a system of differential equations to predict the kinetics of T follicular helper (Tfh) and regulatory T (Treg) cell populations. The model predicted that Tfh cells expanded to larger values following TCDD exposure compared with vehicle and CH223191. Following the initial elevation, both Tfh and Treg cell populations continuously decayed over time. A function based on the ratio of predicted Treg/Tfh cells showed that Treg cells exceed Tfh cells in all groups, with TCDD and CH223191 showing lower Treg/Tfh cell ratios than the vehicle and that the ratio is relatively constant over time. We conclude that AhR ligands did not induce an anti-inflammatory response to attenuate autoimmunity in adult lupus mice. This study challenges the dogma that TCDD supports an immunosuppressive phenotype.


Polychlorinated Dibenzodioxins , Pyrazoles , T-Lymphocytes, Regulatory , Animals , Mice , Azo Compounds , Polychlorinated Dibenzodioxins/pharmacology , Anti-Inflammatory Agents
7.
Front Immunol ; 15: 1359534, 2024.
Article En | MEDLINE | ID: mdl-38352866

Introduction: Leaky gut has been linked to autoimmune disorders including lupus. We previously reported upregulation of anti-flagellin antibodies in the blood of lupus patients and lupus-prone mice, which led to our hypothesis that a leaky gut drives lupus through bacterial flagellin-mediated activation of toll-like receptor 5 (TLR5). Methods: We created MRL/lpr mice with global Tlr5 deletion through CRISPR/Cas9 and investigated lupus-like disease in these mice. Result: Contrary to our hypothesis that the deletion of Tlr5 would attenuate lupus, our results showed exacerbation of lupus with Tlr5 deficiency in female MRL/lpr mice. Remarkably higher levels of proteinuria were observed in Tlr5 -/- MRL/lpr mice suggesting aggravated glomerulonephritis. Histopathological analysis confirmed this result, and Tlr5 deletion significantly increased the deposition of IgG and complement C3 in the glomeruli. In addition, Tlr5 deficiency significantly increased renal infiltration of Th17 and activated cDC1 cells. Splenomegaly and lymphadenopathy were also aggravated in Tlr5-/- MRL/lpr mice suggesting impact on lymphoproliferation. In the spleen, significant decreased frequencies of regulatory lymphocytes and increased germinal centers were observed with Tlr5 deletion. Notably, Tlr5 deficiency did not change host metabolism or the existing leaky gut; however, it significantly reshaped the fecal microbiota. Conclusion: Global deletion of Tlr5 exacerbates lupus-like disease in MRL/lpr mice. Future studies will elucidate the underlying mechanisms by which Tlr5 deficiency modulates host-microbiota interactions to exacerbate lupus.


Glomerulonephritis , Toll-Like Receptor 5 , Animals , Female , Humans , Mice , Glomerulonephritis/pathology , Kidney/pathology , Mice, Inbred MRL lpr , Proteinuria
8.
J Am Vet Med Assoc ; 262(4): 1-4, 2024 Apr 01.
Article En | MEDLINE | ID: mdl-38266392

OBJECTIVE: To evaluate the clinical and histopathological features of a case of xanthogranulomatous keratitis in a mixed-breed dog. ANIMAL: Mixed-breed dog. CLINICAL PRESENTATION, PROGRESSION, AND PROCEDURES: An 11-year-old spayed female mixed-breed dog was presented for mild blepharospasm, corneal cloudiness, and increasing conjunctival hyperemia OD. Ophthalmic examination revealed multifocal pink and cream-colored consolidated corneal infiltrative lesions and generalized neovascularization with suspected diagnosis of stromal abscessation. There was no improvement after 1 month of medical management, so a keratectomy was performed, and corneal tissue was sent for histopathological evaluation. TREATMENT AND OUTCOME: The nonulcerative keratitis was refractive to medical management including topical and systemic antibiotics, topical antifungal, and systemic anti-inflammatory, so keratectomy was performed. Histopathologic diagnosis of xanthogranulomatous keratitis was made 1 week postoperatively. The patient was prescribed 0.05% difluprednate ophthalmic emulsion and 0.2% tacrolimus ophthalmic ointment (initially q 8 h, OD). The difluprednate was tapered and discontinued after 2 months, but the tacrolimus was continued (q 12 h, OD). No lesion recurrence had been documented 1 year postoperatively. CLINICAL RELEVANCE: There has been little published on canine xanthogranulomas, especially in veterinary ophthalmology. Ocular xanthogranulomas have been reportedly found intraocularly and at the ocular surface. Histologically, they are characterized by well-delineated nodules that contain histiocytes and abundant lipid-laden macrophages. The treatment in this clinical case was surgical excision followed with topical immunosuppression/anti-inflammatory therapy with no recurrence 1 year postoperatively. Xanthogranulomatous keratitis should be an added differential diagnosis when nonulcerative keratitis is found on examination, specifically with consolidated, corneal infiltrate and minimal pain.


Corneal Diseases , Dog Diseases , Keratitis , Animals , Dogs , Female , Anti-Bacterial Agents/therapeutic use , Anti-Inflammatory Agents/therapeutic use , Cornea/pathology , Corneal Diseases/veterinary , Dog Diseases/diagnosis , Dog Diseases/surgery , Dog Diseases/drug therapy , Keratitis/diagnosis , Keratitis/veterinary , Keratitis/drug therapy , Tacrolimus/therapeutic use
9.
Blood Adv ; 8(3): 591-602, 2024 02 13.
Article En | MEDLINE | ID: mdl-38052038

ABSTRACT: CD123, a subunit of the interleukin-3 receptor, is expressed on ∼80% of acute myeloid leukemias (AMLs). Tagraxofusp (TAG), recombinant interleukin-3 fused to a truncated diphtheria toxin payload, is a first-in-class drug targeting CD123 approved for treatment of blastic plasmacytoid dendritic cell neoplasm. We previously found that AMLs with acquired resistance to TAG were re-sensitized by the DNA hypomethylating agent azacitidine (AZA) and that TAG-exposed cells became more dependent on the antiapoptotic molecule BCL-2. Here, we report a phase 1b study in 56 adults with CD123-positive AML or high-risk myelodysplastic syndrome (MDS), first combining TAG with AZA in AML/MDS, and subsequently TAG, AZA, and the BCL-2 inhibitor venetoclax (VEN) in AML. Adverse events with 3-day TAG dosing were as expected, without indication of increased toxicity of TAG or AZA+/-VEN in combination. The recommended phase 2 dose of TAG was 12 µg/kg/day for 3 days, with 7-day AZA +/- 21-day VEN. In an expansion cohort of 26 patients (median age 71) with previously untreated European LeukemiaNet adverse-risk AML (50% TP53 mutated), triplet TAG-AZA-VEN induced response in 69% (n=18/26; 39% complete remission [CR], 19% complete remission with incomplete count recovery [CRi], 12% morphologic leukemia-free state [MLFS]). Among 13 patients with TP53 mutations, 7/13 (54%) achieved CR/CRi/MLFS (CR = 4, CRi = 2, MLFS = 1). Twelve of 17 (71%) tested responders had no flow measurable residual disease. Median overall survival and progression-free survival were 14 months (95% CI, 9.5-NA) and 8.5 months (95% CI, 5.1-NA), respectively. In summary, TAG-AZA-VEN shows encouraging safety and activity in high-risk AML, including TP53-mutated disease, supporting further clinical development of TAG combinations. The study was registered on ClinicalTrials.gov as #NCT03113643.


Bridged Bicyclo Compounds, Heterocyclic , Leukemia, Myeloid, Acute , Myelodysplastic Syndromes , Recombinant Fusion Proteins , Sulfonamides , Adult , Aged , Humans , Azacitidine/therapeutic use , Interleukin-3 Receptor alpha Subunit , Leukemia, Myeloid, Acute/genetics , Myelodysplastic Syndromes/genetics , Proto-Oncogene Proteins c-bcl-2
10.
J Asthma ; : 1-13, 2023 Dec 13.
Article En | MEDLINE | ID: mdl-38088937

BACKGROUND: Clinical trials and real world studies demonstrated benefit of mepolizumab treatment in severe asthma but data on its effectiveness beyond 2 years remain limited. Herein, we provide mepolizumab treatment evaluation up to 4 years. METHODS: we studied all patients initiated on mepolizumab in our center from June 2017 to August 2018. Clinical outcomes data were retrieved from the local dendrite systems registry. Comparison analyses and logistic regression were conducted to explore longevity and predictors of response to mepolizumab treatment. RESULTS: a total of 66 patients initiated on mepolizumab with a median follow-up of 45.8 (42.4,48.1) months were included in the study [mean age 50.3 years (range 18-79), females 50 (73%) ]. At 20.7 months of treatment, 42 patients (63.6%) had positive response, 13 (19.7%) negative response, and 11 (16.7%) discontinued due to other factors. At 45.8 months, 35 (53%) patients were still on mepolizumab, 21 (31.8%) switched to a different biologic, and 10 (15.2%) discontinued biologics. Two deaths were recorded during the study period.The median blood eosinophil was reduced from 0.43x109/L (0.27, 0.75) to 0.04 (0.0, 0.1) (p < 0.00001)]. The median annual exacerbations were reduced from 6.0 (4,8) to 1.0 (0.0,3.0) (p < 0.00001), and mOCS use was reduced from59% to 29%, p = 0.001. The mean asthma control questionnaire-6 (ACQ6) improved from 3.1 ± 1.7 to 2.1 ± 1.3 (p < 0.00001). CONCLUSIONS: mepolizumab clinical benefit was sustained over 4 years. However, approximately half of the cohort discontinued the treatment prompting the need for further research into the treatment response longevity.

11.
Immunohorizons ; 7(12): 898-907, 2023 Dec 01.
Article En | MEDLINE | ID: mdl-38153351

We previously demonstrated that the upregulation of microRNAs (miRNAs) at the genomic imprinted Dlk1-Dio3 locus in murine lupus is correlated with global DNA hypomethylation. We now report that the Dlk1-Dio3 genomic region in CD4+ T cells of MRL/lpr mice is hypomethylated, linking it to increased Dlk1-Dio3 miRNA expression. We evaluated the gene expression of methylating enzymes, DNA methyltransferases (DNMTs), and demethylating ten-eleven translocation proteins (TETs) to elucidate the molecular basis of DNA hypomethylation in lupus CD4+ T cells. There was a significantly elevated expression of Dnmt1 and Dnmt3b, as well as Tet1 and Tet2, in CD4+ T cells of three different lupus-prone mouse strains compared to controls. These findings suggest that the hypomethylation of murine lupus CD4+ T cells is likely attributed to a TET-mediated active demethylation pathway. Moreover, we found that deletion of early growth response 2 (Egr2), a transcription factor gene in B6/lpr mice markedly reduced maternally expressed miRNA genes but not paternally expressed protein-coding genes at the Dlk1-Dio3 locus in CD4+ T cells. EGR2 has been shown to induce DNA demethylation by recruiting TETs. Surprisingly, we found that deleting Egr2 in B6/lpr mice induced more hypomethylated differentially methylated regions at either the whole-genome level or the Dlk1-Dio3 locus in CD4+ T cells. Although the role of methylation in EGR2-mediated regulation of Dlk1-Dio3 miRNAs is not readily apparent, these are the first data to show that in lupus, Egr2 regulates Dlk1-Dio3 miRNAs, which target major signaling pathways in autoimmunity. These data provide a new perspective on the role of upregulated EGR2 in lupus pathogenesis.


DNA Methylation , MicroRNAs , Animals , Mice , Mice, Inbred MRL lpr , Autoimmunity , Mice, Inbred C57BL , MicroRNAs/genetics , DNA , Calcium-Binding Proteins/genetics , Early Growth Response Protein 2
13.
J Leukoc Biol ; 114(6): 547-556, 2023 11 24.
Article En | MEDLINE | ID: mdl-37804110

Systemic lupus erythematosus (SLE) is an autoimmune disease caused by environmental factors and loss of key proteins, including the endonuclease Dnase1L3. Dnase1L3 absence causes pediatric-onset lupus in humans, while reduced activity occurs in adult-onset SLE. The amount of Dnase1L3 that prevents lupus remains unknown. To genetically reduce Dnase1L3 levels, we developed a mouse model lacking Dnase1L3 in macrophages (conditional knockout [cKO]). Serum Dnase1L3 levels were reduced 67%, though Dnase1 activity remained constant. Homogeneous and peripheral antinuclear antibodies were detected in the sera by immunofluorescence, consistent with anti-double-stranded DNA (anti-dsDNA) antibodies. Total immunoglobulin M, total immunoglobulin G, and anti-dsDNA antibody levels increased in cKO mice with age. The cKO mice developed anti-Dnase1L3 antibodies. In contrast to global Dnase1L3-/- mice, anti-dsDNA antibodies were not elevated early in life. The cKO mice had minimal kidney pathology. Therefore, we conclude that an intermediate reduction in serum Dnase1L3 causes mild lupus phenotypes, and macrophage-derived DnaselL3 helps limit lupus.


DNA , Lupus Erythematosus, Systemic , Humans , Adult , Child , Mice , Animals , DNA/metabolism , Endodeoxyribonucleases/genetics , Endodeoxyribonucleases/metabolism , Kidney/pathology , Macrophages/metabolism
15.
Sci Rep ; 13(1): 13790, 2023 08 23.
Article En | MEDLINE | ID: mdl-37612326

Heat shock protein 90 (Hsp90) and its co-chaperones promote cancer, and targeting Hsp90 holds promise for cancer treatment. Most of the efforts to harness this potential have focused on targeting the Hsp90 N-terminus ATP binding site. Although newer-generation inhibitors have shown improved efficacy in aggressive cancers, induction of the cellular heat shock response (HSR) by these inhibitors is thought to limit their clinical efficacy. Therefore, Hsp90 inhibitors with novel mechanisms of action and that do not trigger the HSR would be advantageous. Here, we investigated the mechanism by which capsaicin inhibits Hsp90. Through mutagenesis, chemical modifications, and proteomic studies, we show that capsaicin binds to the N-terminus of Hsp90 and inhibits its ATPase activity. Consequently, capsaicin and its analogs inhibit Hsp90 ATPase-dependent progesterone receptor reconstitution in vitro. Capsaicin did not induce the HSR, instead, it promoted the degradation of Hsp70 through the lysosome-autophagy pathway. Remarkably, capsaicin did not induce degradation of the constitutively expressed cognate Hsc70, indicating selectivity for Hsp70. Combined treatments of capsaicin and the Hsp90 inhibitor 17-AAG improved the anti-tumor efficacy of 17-AAG in cell culture and tridimensional tumor spheroid growth assays using breast and prostate cancer models. Consistent with this, in silico docking studies revealed that capsaicin binding to the ATP binding site of Hsp90 was distinct from classical N-terminus Hsp90 inhibitors, indicating a novel mechanism of action. Collectively, these findings support the use of capsaicin as a chemical scaffold to develop novel Hsp90 N-terminus inhibitors as well as its ability to be a potential cancer co-therapeutic.


Capsaicin , Prostatic Neoplasms , Male , Humans , Capsaicin/pharmacology , Proteomics , HSP70 Heat-Shock Proteins , HSP90 Heat-Shock Proteins , Lysosomes , Adenosine Triphosphatases , Adenosine Triphosphate
16.
bioRxiv ; 2023 Aug 11.
Article En | MEDLINE | ID: mdl-37577550

Asthma is deemed an inflammatory disease, yet the defining diagnostic symptom is mechanical bronchoconstriction. We previously discovered a conserved process that drives homeostatic epithelial cell death in response to mechanical cell crowding called cell extrusion(1, 2). Here, we show that the pathological crowding of a bronchoconstrictive attack causes so much epithelial cell extrusion that it damages the airways, resulting in inflammation and mucus secretion. While relaxing airways with the rescue treatment albuterol did not impact these responses, inhibiting live cell extrusion signaling during bronchoconstriction prevented all these symptoms. Our findings propose a new etiology for asthma, dependent on the mechanical crowding of a bronchoconstrictive attack. Our studies suggest that blocking epithelial extrusion, instead of ensuing downstream inflammation, could prevent the feed-forward asthma inflammatory cycle.

17.
Front Chem ; 11: 1238711, 2023.
Article En | MEDLINE | ID: mdl-37588512

Recent state-to-state experiments of methane scattering from Ni(111) and graphene-covered Ni(111) combined with quantum mechanical simulations suggest an intriguing correlation between the surface-induced vibrational energy redistribution (SIVR) during the molecule/surface scattering event and the catalytic activity for methane dissociation of the target surface (Werdecker, Phys. Rev. Res., 2020, 2, 043251). Herein, we report new quantum state and angle-resolved measurements for methane scattering from Ni(111) and Au(111) probing the extent of ν3→ν1 antisymmetric-to-symmetric conversion of methane stretching motion for two surfaces with different catalytic activities. Consistent with the expectations, the extent of SIVR occurring on the more catalytically active Ni(111) surface, as measured by the ν1:ν3 scattered population ratio, is found to be several times stronger than that on the more inert Au(111) surface. We also present additional insights on the rovibrational scattering dynamics contained in the angle- and state-resolved data. The results together highlight the power of state-resolved scattering measurements as a tool for investigating methane-surface interactions.

18.
19.
Sci Rep ; 13(1): 11864, 2023 07 22.
Article En | MEDLINE | ID: mdl-37481609

While sustained-release buprenorphine (BSR) is used as a long-lasting opioid analgesic in common marmosets (Callithrix jacchus), there are no published studies on pharmaceutical-grade extended-release buprenorphine options such as Ethiqa XR (EXR) for this species. However, BSR is a compounded product and has been reported to cause injection site reactions in multiple species, including marmosets. Additionally, now with the availability of EXR, a pharmaceutical-grade veterinary product, the use of BSR in laboratory animals is not compliant with the Guide for the Care and Use of Laboratory Animals (Guide) unless scientifically justified and approved by the IACUC. We compared pharmacokinetic and safety profiles of BSR (0.15 mg/kg) and EXR (0.1-0.2 mg/kg) administered subcutaneously to adult marmosets. Blood was collected by venipuncture of the saphenous vein at multiple time points (0.25-72 h) and analyzed by liquid chromatography-tandem mass spectrometry (LC-MS/MS). EXR between 0.1 and 0.2 mg/kg resulted in a dose-dependent increase in Cmax (1.43-2.51 ng/mL) and were not statistically different from BSR (1.82 ng/mL). Tmax, lambdaz, and t1/2 were not statistically different between formulations. Mean plasma buprenorphine concentrations for BSR and EXR exceeded the therapeutic threshold (0.1 ng/mL) within 0.25 h and lasted for > 72 h. Mild sedation, but neither respiratory depression nor ataxia, was observed for both formulations. BSR injection sites had significantly higher histopathological scores compared to EXR. Video recordings for monitoring drug-induced behavioral changes showed increased animal activity levels after BSR and EXR versus saline controls. Norbuprenorphine, a buprenorphine metabolite associated with respiratory depression, was detected in the plasma after BSR and EXR administration as well as by in vitro liver microsome assays. In conclusion, we recommend using EXR over BSR as a long-lasting buprenorphine analgesic in marmosets because EXR is a pharmaceutical-grade formulation that is compliant with FDA guidelines and the Guide as well as exhibits comparable PK and safety profiles as BSR.


Buprenorphine , Callithrix , Animals , Delayed-Action Preparations , Chromatography, Liquid , Tandem Mass Spectrometry , Callitrichinae
20.
J Chem Phys ; 158(21)2023 Jun 07.
Article En | MEDLINE | ID: mdl-37260006

We describe a novel ultrahigh vacuum state-to-state molecule/surface scattering apparatus with quantum state preparation of the incident molecular beam and angle-resolved quantum state detection of the scattered molecules. State-resolved detection is accomplished using a tunable mid-infrared laser source combined with a cryogenic bolometer detector and is applicable to any molecule with an infrared-active vibrational transition. Results on rotationally inelastic scattering of CH4 methane from a Ni(111) surface and NiO(111)/Ni(111) oxide film, obtained by the new apparatus, are presented. Molecules scattering from the oxidized surface, compared to those scattering from the bare nickel surface, are more highly excited rotationally and scatter into a broader distribution of angles. The internal alignment of molecular rotation is in addition found to be stronger in molecules scattering from the bare surface. Furthermore, the maxima of the state-resolved angular distributions shift toward and away from surface normal with increasing rotational quantum number J for the oxidized and bare surface, respectively. Finally, the rotational state populations produced in scattering from the oxidized surface are well-described by a Boltzmann distribution, while those produced in scattering from the bare surface exhibit large deviations from their best-fit Boltzmann distributions. These results point toward a marked enhancement in molecule-surface collisional energy exchange induced by oxidation of the nickel surface.

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