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1.
PLoS Pathog ; 19(10): e1011748, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37871123

RESUMO

Acquired stress resistance (ASR) enables organisms to prepare for environmental changes that occur after an initial stressor. However, the genetic basis for ASR and how the underlying network evolved remain poorly understood. In this study, we discovered that a short phosphate starvation induces oxidative stress response (OSR) genes in the pathogenic yeast C. glabrata and protects it against a severe H2O2 stress; the same treatment, however, provides little benefit in the low pathogenic-potential relative, S. cerevisiae. This ASR involves the same transcription factors (TFs) as the OSR, but with different combinatorial logics. We show that Target-of-Rapamycin Complex 1 (TORC1) is differentially inhibited by phosphate starvation in the two species and contributes to the ASR via its proximal effector, Sch9. Therefore, evolution of the phosphate starvation-induced ASR involves the rewiring of TORC1's response to phosphate limitation and the repurposing of TF-target gene networks for the OSR using new regulatory logics.


Assuntos
Proteínas de Saccharomyces cerevisiae , Saccharomyces cerevisiae , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo , Alvo Mecanístico do Complexo 1 de Rapamicina , Peróxido de Hidrogênio , Fosfatos , Regulação Fúngica da Expressão Gênica
2.
Proc Natl Acad Sci U S A ; 119(15): e2116576119, 2022 04 12.
Artigo em Inglês | MEDLINE | ID: mdl-35377807

RESUMO

In studies of vision and audition, stimuli can be chosen to span the visible or audible spectrum; in olfaction, the axes and boundaries defining the analogous odorous space are unknown. As a result, the population of olfactory space is likewise unknown, and anecdotal estimates of 10,000 odorants have endured. The journey a molecule must take to reach olfactory receptors (ORs) and produce an odor percept suggests some chemical criteria for odorants: a molecule must 1) be volatile enough to enter the air phase, 2) be nonvolatile and hydrophilic enough to sorb into the mucous layer coating the olfactory epithelium, 3) be hydrophobic enough to enter an OR binding pocket, and 4) activate at least one OR. Here, we develop a simple and interpretable quantitative model that reliably predicts whether a molecule is odorous or odorless based solely on the first three criteria. Applying our model to a database of all possible small organic molecules, we estimate that at least 40 billion possible compounds are odorous, six orders of magnitude larger than current estimates of 10,000. With this model in hand, we can define the boundaries of olfactory space in terms of molecular volatility and hydrophobicity, enabling representative sampling of olfactory stimulus space.


Assuntos
Odorantes , Olfato , Compostos Orgânicos Voláteis , Animais , Humanos , Aprendizado de Máquina , Modelos Teóricos , Receptores Odorantes , Compostos Orgânicos Voláteis/química , Compostos Orgânicos Voláteis/classificação , Volatilização
3.
J Bacteriol ; 202(22)2020 10 22.
Artigo em Inglês | MEDLINE | ID: mdl-32868404

RESUMO

Clostridioides (Clostridium) difficile is a major cause of hospital-acquired infections leading to antibiotic-associated diarrhea. C. difficile exhibits a very high level of resistance to lysozyme. Bacteria commonly resist lysozyme through modification of the cell wall. In C. difficile, σV is required for lysozyme resistance, and σV is activated in response to lysozyme. Once activated, σV, encoded by csfV, directs transcription of genes necessary for lysozyme resistance. Here, we analyze the contribution of individual genes in the σV regulon to lysozyme resistance. Using CRISPR-Cas9-mediated mutagenesis we constructed in-frame deletions of single genes in the csfV operon. We find that pdaV, which encodes a peptidoglycan deacetylase, is partially responsible for lysozyme resistance. We then performed CRISPR inhibition (CRISPRi) to identify a second peptidoglycan deacetylase, encoded by pgdA, that is important for lysozyme resistance. Deletion of either pgdA or pdaV resulted in modest decreases in lysozyme resistance. However, deletion of both pgdA and pdaV resulted in a 1,000-fold decrease in lysozyme resistance. Further, muropeptide analysis revealed that loss of either PgdA or PdaV had modest effects on peptidoglycan deacetylation but that loss of both PgdA and PdaV resulted in almost complete loss of peptidoglycan deacetylation. This suggests that PgdA and PdaV are redundant peptidoglycan deacetylases. We also used CRISPRi to compare other lysozyme resistance mechanisms and conclude that peptidoglycan deacetylation is the major mechanism of lysozyme resistance in C. difficileIMPORTANCEClostridioides difficile is the leading cause of hospital-acquired diarrhea. C. difficile is highly resistant to lysozyme. We previously showed that the csfV operon is required for lysozyme resistance. Here, we used CRISPR-Cas9 mediated mutagenesis and CRISPRi knockdown to show that peptidoglycan deacetylation is necessary for lysozyme resistance and is the major lysozyme resistance mechanism in C. difficile We show that two peptidoglycan deacetylases in C. difficile are partially redundant and are required for lysozyme resistance. PgdA provides an intrinsic level of deacetylation, and PdaV, encoded by a part of the csfV operon, provides lysozyme-induced peptidoglycan deacetylation.


Assuntos
Amidoidrolases/metabolismo , Proteínas de Bactérias/metabolismo , Clostridioides difficile/enzimologia , Muramidase/metabolismo , Peptidoglicano/química , Amidoidrolases/genética , Proteínas de Bactérias/genética , Clostridioides difficile/patogenicidade , Regulação Bacteriana da Expressão Gênica , Óperon , Virulência
4.
J Neurosci ; 36(42): 10769-10781, 2016 10 19.
Artigo em Inglês | MEDLINE | ID: mdl-27798132

RESUMO

Designer receptors exclusively activated by designer drugs (DREADDs) are an advanced experimental tool that could potentially provide a novel approach to pain management. In particular, expression of an inhibitory (Gi-coupled) DREADD in nociceptors might enable ligand-dependent analgesia. To test this possibility, TRPV1-cre mice were used to restrict expression of Gi-DREADDs to predominantly C-fibers. Whereas baseline heat thresholds in both male and female mice expressing Gi-DREADD were normal, 1 mg/kg clozapine-N-oxide (CNO) produced a significant 3 h increase in heat threshold that returned to baseline by 5 h after injection. Consistent with these behavioral results, CNO decreased action potential firing in isolated sensory neurons from Gi-DREADD mice. Unexpectedly, however, the expression of Gi-DREADD in sensory neurons caused significant changes in voltage-gated Ca2+ and Na+ currents in the absence of CNO, as well as an increase in Na+ channel (NaV1.7) expression. Furthermore, CNO-independent excitatory and inhibitory second-messenger signaling was also altered in these mice, which was associated with a decrease in the analgesic effect of endogenous inhibitory G-protein-coupled receptor activation. These results highlight the potential of this exciting technology, but also its limitations, and that it is essential to identify the underlying mechanisms for any observed behavioral phenotypes. SIGNIFICANCE STATEMENT: DREADD technology is a powerful tool enabling manipulation of activity and/or transmitter release from targeted cell populations. The purpose of this study was to determine whether inhibitory DREADDs in nociceptive afferents could be used to produce analgesia, and if so, how. DREADD activation produced a ligand-dependent analgesia to heat in vivo and a decrease in neuronal firing at the single-cell level. However, we observed that expression of Gi-DREADD also causes ligand-independent changes in ion channel activity and second-messenger signaling. These findings highlight both the potential and the limitations of this exciting technology as well as the necessity to identify the mechanisms underlying any observed phenotype.


Assuntos
Analgesia , Drogas Desenhadas/farmacologia , Nervos Periféricos/metabolismo , Células Receptoras Sensoriais/efeitos dos fármacos , Animais , Comportamento Animal/efeitos dos fármacos , Canais de Cálcio/efeitos dos fármacos , Clozapina/farmacologia , Feminino , Masculino , Camundongos , Nociceptores/efeitos dos fármacos , Medição da Dor/efeitos dos fármacos , Limiar da Dor/efeitos dos fármacos , Técnicas de Patch-Clamp , Canais de Potássio de Abertura Dependente da Tensão da Membrana/efeitos dos fármacos , Receptores Acoplados a Proteínas G/efeitos dos fármacos , Sistemas do Segundo Mensageiro/efeitos dos fármacos , Canais de Cátion TRPV/efeitos dos fármacos
5.
Dev Biol ; 414(2): 149-60, 2016 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-27151208

RESUMO

Auditory information is initially processed in the cochlear nuclei before being relayed to the brain. The cochlear nuclei are subdivided into dorsal, anterior ventral, and posterior ventral domains, each containing several subtypes of neurons that are thought to play discrete roles in the processing of sound. However, the ontogeny of these neurons is poorly understood, and this gap in knowledge hampers efforts to understand the basic neural circuitry of this nucleus. Here, we reveal that Bhlhb5 is expressed in both excitatory (unipolar brush cells) and inhibitory neurons (cartwheel cells) of the DCN during development. To gain genetic access to Bhlhb5-expressing neurons in the DCN, we generated a Bhlhb5::flpo knockin allele. Using an intersectional genetic strategy, we labeled cartwheel cells, thereby providing proof of concept that subpopulations of Bhlhb5-expressing neurons can be genetically targeted. Moreover, fate-mapping experiments using this allele revealed that Bhlhb5 is required for the proper development of the DCN, since mice lacking Bhlhb5 showed a dramatically diminished number of neurons, including unipolar brush and cartwheel cells. Intriguingly, the Bhlhb5::flpo allele also genetically labels numerous other regions of the nervous system that process sensory input, including the dorsal horn, the retina, and the nucleus of the lateral olfactory tract, hinting at a more general role for Bhlhb5 in the development of neurons that mediate sensory integration.


Assuntos
Fatores de Transcrição Hélice-Alça-Hélice Básicos/fisiologia , Núcleo Coclear/crescimento & desenvolvimento , Células Receptoras Sensoriais/metabolismo , Alelos , Animais , Fatores de Transcrição Hélice-Alça-Hélice Básicos/deficiência , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Contagem de Células , Linhagem da Célula , Núcleo Coclear/embriologia , Núcleo Coclear/metabolismo , Regulação da Expressão Gênica no Desenvolvimento , Técnicas de Introdução de Genes , Proteínas Luminescentes/análise , Camundongos , Camundongos Knockout , Bulbo Olfatório/metabolismo , Fator de Transcrição PAX6/metabolismo , Células do Corno Posterior/metabolismo , Retina/metabolismo
6.
Genesis ; 54(11): 593-601, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27712014

RESUMO

The Neurokinin 1 Receptor (NK1R), which binds Substance P, is expressed in discrete populations of neurons throughout the nervous system, where it has numerous roles including the modulation of pain and affective behaviors. Here, we report the generation of a NK1R-CreER knockin allele, in which CreERT2 replaces the coding sequence of the TACR1 gene (encoding NK1R) in order to gain genetic access to these cells. We find that the NK1R-CreER allele mediates recombination in many regions of the nervous system that are important in pain and anxiety including the amygdala, hypothalamus, frontal cortex, raphe nucleus, and dorsal horn of the spinal cord. Other cell types that are labeled by this allele include amacrine cells in the retina and fibroblasts in the skin. Thus, the NK1R-CreER mouse line is a valuable new tool for conditional gene manipulation enabling the visualization and manipulation of cells that express NK1R.


Assuntos
Neurônios/metabolismo , Dor/genética , Receptores da Neurocinina-1/genética , Animais , Regulação da Expressão Gênica , Técnicas de Introdução de Genes , Integrases/genética , Camundongos , Dor/patologia , Receptores da Neurocinina-1/metabolismo , Transdução de Sinais/genética , Medula Espinal/crescimento & desenvolvimento , Medula Espinal/metabolismo , Substância P/genética , Substância P/metabolismo
7.
Genesis ; 54(1): 29-37, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26575788

RESUMO

The kappa opioid receptor (KOR) has numerous important roles in the nervous system including the modulation of mood, reward, pain, and itch. In addition, KOR is expressed in many non-neuronal tissues. However, the specific cell types that express KOR are poorly characterized. Here, we report the development of a KOR-Cre knockin allele, which provides genetic access to cells that express KOR. In this mouse, Cre recombinase (Cre) replaces the initial coding sequence of the Opkr1 gene (encoding the kappa opioid receptor). We demonstrate that the KOR-Cre allele mediates recombination by embryonic day 14.5 (E14.5). Within the brain, KOR-Cre shows expression in numerous areas including the cerebral cortex, nucleus accumbens and striatum. In addition, this allele is expressed in epithelium and throughout many regions of the body including the heart, lung, and liver. Finally, we reveal that KOR-Cre mediates recombination of a subset of bipolar and amacrine cells in the retina. Thus, the KOR-Cre mouse line is a valuable new tool for conditional gene manipulation to enable the study of KOR.


Assuntos
Técnicas de Transferência de Genes , Receptores Opioides kappa/genética , Receptores Opioides kappa/metabolismo , Animais , Encéfalo/metabolismo , Feminino , Integrases/química , Integrases/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Modelos Animais , Receptores Opioides kappa/biossíntese , Transdução de Sinais
8.
Vet Anaesth Analg ; 43(1): 86-90, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26010765

RESUMO

OBJECTIVE: To evaluate and compare the time to extubation in two commonly used methods of analgesia in dogs undergoing elective pelvic limb orthopedic procedures. STUDY DESIGN: Prospective, randomized, double-blinded clinical study. ANIMALS: Twenty-five adult, client-owned, healthy dogs aged 4.4 ± 1.6 years and weighing 38.5 ±3.5 kg. METHODS: All dogs were premedicated with dexmedetomidine (5-10 µg kg(-1)) intramuscularly (IM) and anesthesia was induced with propofol (2-6 mg kg(-1)) intravenously (IV). Atipamazole (0.05-0.1 mg kg(-1)) was administered IM after instrumentation. Anesthesia was maintained with isoflurane in oxygen. Dogs were randomly assigned to one of two groups. In one group, morphine (0.1 mg kg(-1)) and lidocaine (2% lidocaine added to a total volume of 0.2 mL kg(-1)) were administered epidurally and a saline placebo constant rate infusion (CRI) was administered IV (group EPI). In the other group (group MLK), morphine (4 µg kg(-1) minute(-1)), lidocaine (50 µg kg(-1) minute(-1)) and ketamine (10 µg kg(-1) minute(-1)) were administered as an IV CRI and a saline placebo was administered by epidural injection. Temperature at the discontinuation of isoflurane, temperature at extubation, time to extubation, duration of inhalation anesthesia and duration of surgery were recorded. RESULTS: No significant differences between the groups were found in time to extubation, temperature at the end of surgery, temperature at extubation and total surgical time. Total anesthesia time was significantly longer in group EPI. CONCLUSIONS AND CLINICAL RELEVANCE: Administration of MLK at the doses reported in this study did not prolong the time to extubation in comparison with a morphine-lidocaine epidural nerve block. The results indicate that concern over prolonging the time to extubation is not a reason to avoid the administration of MLK.


Assuntos
Analgésicos/farmacologia , Anestesia Geral/veterinária , Cães/fisiologia , Analgésicos/administração & dosagem , Período de Recuperação da Anestesia , Animais , Feminino , Infusões Intravenosas/veterinária , Injeções Epidurais/veterinária , Intubação Intratraqueal/veterinária , Ketamina/administração & dosagem , Ketamina/farmacologia , Lidocaína/administração & dosagem , Lidocaína/farmacologia , Masculino , Morfina/administração & dosagem , Morfina/farmacologia , Osteotomia/veterinária , Tíbia/cirurgia
9.
J Vet Dent ; 33(2): 90-96, 2016 06.
Artigo em Inglês | MEDLINE | ID: mdl-28326977

RESUMO

Bupivacaine appears to have a duration of action longer than previously reported. Results of this study demonstrate that the addition of buprenorphrine may enhance the analgesic duration of effect for bupivacaine regional nerve blocks. In addition, the use of bupivacaine alone may have analgesia that exceeds 24 hours in many cases. Although not statistically significant based on sample size, 50% of dogs receiving the bupivacaine/buprenorphine regional anesthetic block demonstrated a decreased anesthetic requirement 48 hours postadministration when compared to 25% of dogs receiving the bupivacaine anesthetic. No adverse cardiorespiratory effects were noted secondary to either local anesthetic treatment. Use of bupivacaine may have analgesic effects extending greater than 24 hours (24-72) when used in regional anesthetic blocks in veterinary dental patients with acute dental pain. The addition of buprenorphine to bupivacaine may extend the duration of analgesia (48-96 h). The limited sample size, in addition to patient variability in response to medications, may account for the fact that no differences were detected between the treatments administered.


Assuntos
Bupivacaína/farmacologia , Buprenorfina/farmacologia , Bloqueio Nervoso/veterinária , Dor Pós-Operatória/veterinária , Anestésicos Locais , Animais , Bupivacaína/administração & dosagem , Buprenorfina/administração & dosagem , Doenças do Cão/cirurgia , Cães , Isoflurano/administração & dosagem , Bloqueio Nervoso/métodos , Dor Pós-Operatória/tratamento farmacológico , Dor Pós-Operatória/prevenção & controle
10.
Handb Exp Pharmacol ; 226: 191-206, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25861781

RESUMO

Recent studies have made significant progress in the knowledge of how itch sensation is processed, especially the molecular identity of neurons involved in itch signaling, both in the dorsal root ganglion and spinal cord. Despite these advances, the organization of these neurons in dorsal spinal cord circuits and how they interact with other somatosensory modalities, such as pain or temperature, remain relatively unexplored. Recent work from our lab and others has begun to shed light on these questions and will be the focus of this chapter. Here we describe the discovery of B5-I neurons, a population of inhibitory interneurons that function to inhibit itch, and review the evidence that these neurons mediate the inhibition of itch by counter stimuli. These studies are helping to solve the long-standing question of why itch makes us scratch.


Assuntos
Interneurônios/fisiologia , Prurido/fisiopatologia , Animais , Fatores de Transcrição Hélice-Alça-Hélice Básicos/fisiologia , Humanos , Camundongos , Prurido/prevenção & controle , Receptores Opioides kappa/agonistas , Sensação
11.
Bioorg Med Chem Lett ; 23(9): 2801-7, 2013 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-23540644

RESUMO

Cathepsin L is a cysteine protease that is upregulated in a variety of malignant tumors and plays a significant role in cancer cell invasion and migration. It is an attractive target for the development of small-molecule inhibitors, which may prove beneficial as treatment agents to limit or arrest cancer metastasis. We have previously identified a structurally diverse series of thiosemicarbazone-based inhibitors that incorporate the benzophenone and thiochromanone molecular scaffolds. Herein we report an important extension of this work designed to explore fused aryl-alkyl ring molecular systems that feature nitrogen atom incorporation (dihydroquinoline-based) and carbon atom exclusivity (tetrahydronaphthalene-based). In addition, analogues that contain oxygen (chromanone-based), sulfur (thiochroman-based), sulfoxide, and sulfone functionalization have been prepared in order to further investigate the structure-activity relationship aspects associated with these compounds and their ability to inhibit cathepsins L and B. From this small-library of 30 compounds, five were found to be strongly inhibitory (IC50 <500 nM) against cathepsin L with the most active compound (7-bromodihydroquinoline thiosemicarbazone 48) demonstrating an IC50=164 nM. All of the compounds evaluated were inactive (IC50 >10,000 nM) as inhibitors of cathepsin B, thus establishing a high degree (>20-fold) of selectivity (cathepsin L vs. cathepsin B) for the most active cathepsin L inhibitors in this series.


Assuntos
Catepsina L/antagonistas & inibidores , Inibidores de Proteases/química , Bibliotecas de Moléculas Pequenas/química , Catepsina B/antagonistas & inibidores , Catepsina B/metabolismo , Catepsina L/metabolismo , Cromanos/química , Inibidores de Proteases/síntese química , Inibidores de Proteases/metabolismo , Ligação Proteica , Quinolinas/química , Safrol/análogos & derivados , Safrol/química , Bibliotecas de Moléculas Pequenas/síntese química , Bibliotecas de Moléculas Pequenas/metabolismo , Relação Estrutura-Atividade , Sulfonas/química , Tetra-Hidronaftalenos/química
12.
Vet Clin North Am Equine Pract ; 29(1): 169-78, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23498051

RESUMO

The purpose of this article is to update the community of veterinarians performing general anesthesia in horses on fluid therapy. The rationale behind intraoperative fluid therapy, fluid dynamics, and various fluid options (crystalloids, hypertonic saline, colloids) is discussed. Additionally, electrolytes (calcium, potassium, and sodium) are included in the discussion in relation to general anesthesia and intraoperative fluid management.


Assuntos
Anestesia Geral/veterinária , Hidratação/veterinária , Cavalos/fisiologia , Cuidados Intraoperatórios/veterinária , Animais , Coloides/uso terapêutico , Soluções Cristaloides , Eletrólitos/metabolismo , Soluções Isotônicas , Equilíbrio Hidroeletrolítico/fisiologia
13.
Genetics ; 223(4)2023 04 06.
Artigo em Inglês | MEDLINE | ID: mdl-36794645

RESUMO

Opportunistic yeast pathogens arose multiple times in the Saccharomycetes class, including the recently emerged, multidrug-resistant (MDR) Candida auris. We show that homologs of a known yeast adhesin family in Candida albicans, the Hyr/Iff-like (Hil) family, are enriched in distinct clades of Candida species as a result of multiple, independent expansions. Following gene duplication, the tandem repeat-rich region in these proteins diverged extremely rapidly and generated large variations in length and ß-aggregation potential, both of which are known to directly affect adhesion. The conserved N-terminal effector domain was predicted to adopt a ß-helical fold followed by an α-crystallin domain, making it structurally similar to a group of unrelated bacterial adhesins. Evolutionary analyses of the effector domain in C. auris revealed relaxed selective constraint combined with signatures of positive selection, suggesting functional diversification after gene duplication. Lastly, we found the Hil family genes to be enriched at chromosomal ends, which likely contributed to their expansion via ectopic recombination and break-induced replication. Combined, these results suggest that the expansion and diversification of adhesin families generate variation in adhesion and virulence within and between species and are a key step toward the emergence of fungal pathogens.


Assuntos
Proteínas Fúngicas , Leveduras , Humanos , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Leveduras/metabolismo , Candida albicans/genética , Candida albicans/metabolismo , Candida , Adesinas Bacterianas/metabolismo
14.
bioRxiv ; 2023 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-37781605

RESUMO

Acquired stress resistance (ASR) enables organisms to prepare for environmental changes that occur after an initial stressor. However, the genetic basis for ASR and how the underlying network evolved remain poorly understood. In this study, we discovered that a short phosphate starvation induces oxidative stress response (OSR) genes in the pathogenic yeast C. glabrata and protects it against a severe H2O2 stress; the same treatment, however, provides little benefit in the low pathogenic-potential relative, S. cerevisiae. This ASR involves the same transcription factors (TFs) as the OSR, but with different combinatorial logics. We show that Target-of-Rapamycin Complex 1 (TORC1) is differentially inhibited by phosphate starvation in the two species and contributes to the ASR via its proximal effector, Sch9. Therefore, evolution of the phosphate starvation-induced ASR involves the rewiring of TORC1's response to phosphate limitation and the repurposing of TF-target gene networks for the OSR using new regulatory logics.

15.
Helicobacter ; 17(5): 382-90, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22967122

RESUMO

BACKGROUND: A combination capsule of bismuth, metronidazole, and tetracycline plus omeprazole given as 10-day therapy has an overall effectiveness of 92-93% in per-protocol analysis (Grade B) with eradication of 86-91% of metronidazole-resistant Helicobacter pylori. This study aimed to explore whether extending the duration to 14 days would improve overall effectiveness per protocol to ≥95% (Grade A) in a population in which metronidazole resistance was anticipated to exist. METHODS: A one-arm, open-label pilot study of H. pylori-infected, asymptomatic/mildly dyspeptic adults, Hispanic residents of El Paso, Texas, received a 14-day course of omeprazole, plus the combination capsule. We cultured and Gram-stained specimens obtained using a minimally invasive orogastric brush. Helicobacter pylori status was determined by (13)C-urea breath test at 4 or more weeks post-therapy. RESULTS: Forty-seven subjects (7 men and 40 women, average age 42 years) were entered. The per-protocol effectiveness was 97.1% (33/34) (95% mid-P CI: 86.3, 99.9); 100% of metronidazole-resistant strains were eradicated. Side effects were mild and self-limited but contributed to nonadherence. Therapy taken for <10 days was more likely to result in eradication failure (p < .001). Office-based orogastric brushing was well tolerated; positive cultures were obtained in 95%. Gram staining showed H. pylori-like forms in all specimens. CONCLUSIONS: This pilot study supports the concept that 14-day OBMT therapy is likely to be more efficacious for H. pylori eradication (Grade A, PP basis) than a 10-day course where metronidazole resistance is suspected. If confirmed, 14 days should be recommended in populations where metronidazole resistance is common.


Assuntos
Antibacterianos/administração & dosagem , Bismuto/administração & dosagem , Infecções por Helicobacter/tratamento farmacológico , Administração Oral , Adulto , Idoso , Testes Respiratórios , Quimioterapia Combinada/métodos , Feminino , Helicobacter pylori/isolamento & purificação , Hispânico ou Latino , Humanos , Masculino , Metronidazol/administração & dosagem , Pessoa de Meia-Idade , Omeprazol/administração & dosagem , Projetos Piloto , Tetraciclina/administração & dosagem , Texas , Fatores de Tempo , Resultado do Tratamento , Ureia/análise
16.
Cardiol Res Pract ; 2022: 8244047, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36275928

RESUMO

Background: Elderly patients undergoing hip or knee arthroplasty are at a risk for myocardial injury after noncardiac surgery (MINS). We evaluated the ability of five common cardiac risk scores, alone or combined with baseline high-sensitivity cardiac troponin I (hs-cTnI), in predicting MINS and postoperative day 2 (POD2) hs-cTnI levels in patients undergoing elective total hip or knee arthroplasty. Methods: This study is ancillary to the Genetics-InFormatics Trial (GIFT) of Warfarin Therapy to Prevent Deep Venous Thrombosis, which enrolled patients 65 years and older undergoing elective total hip or knee arthroplasty. The five cardiac risk scores evaluated were the atherosclerotic cardiovascular disease calculator (ASCVD), the Framingham risk score (FRS), the American College of Surgeon's National Surgical Quality Improvement Program (ACS-NSQIP) calculator, the revised cardiac risk index (RCRI), and the reconstructed RCRI (R-RCRI). Results: None of the scores predicted MINS in women. Among men, the ASCVD (C-statistic of 0.66; p=0.04), ACS-NSQIP (C-statistic of 0.69; p=0.01), and RCRI (C-statistic of 0.64; p=0.04) predicted MINS. Among all patients, spearman correlations (r s) of the risk scores with the POD2 hs-cTnI levels were 0.24, 0.20, 0.11, 0.11, and 0.08 for the ASCVD, Framingham, ACS-NSQIP, RCRI, and R-RCRI scores, respectively, with p values of <0.001, <0.001, <0.001, 0.006, and 0.025. Baseline hs-cTnI predicted MINS (C-statistics: 0.63 in women and 0.72 in men) and postoperative hs-cTnI (r s = 0.51, p=0.001). Conclusion: In elderly patients undergoing elective hip or knee arthroplasty, several of the scores modestly predicted MINS in men and correlated with POD2 hs-cTnI.

17.
Nucleic Acids Res ; 37(19): e127, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19679642

RESUMO

In both research and therapeutic applications of RNA interference, it is often advantageous to silence several targets simultaneously. Toward this end, several groups have developed vectors that utilize the model of endogenously encoded micro (mi) RNAs, where a single RNA polymerase II promoter can drive the expression of multiple interfering RNAs. Stronger pol III promoters have been used to drive individual short hairpin (sh) RNAs, but to date, it has been necessary to repeat the promoter in each silencing cassette to achieve multiplexed expression from a single vector. Here, we show that it is possible to drive polycistronic expression from a single pol III promoter when the interfering RNAs are formatted to resemble miRNAs rather than shRNAs. As many as four miRNAs designed to target hepatitis B virus (HBV) transcripts are shown to be processed and functional in reporter assays as well as in the context of replicating virus in cell culture systems. Although it has been observed that high levels of expression of shRNAs can lead to cytotoxicity, we find no significant evidence in transient transfection assays that the HBV-miRNAs produced by our vectors compete for the activity of endogenously produced miR-122 or for processing of an exogenously expressed miR-EGFP.


Assuntos
Interferência de RNA , RNA Polimerase III/metabolismo , Linhagem Celular Tumoral , Vírus da Hepatite B/genética , Vírus da Hepatite B/fisiologia , Humanos , MicroRNAs/química , MicroRNAs/metabolismo , Regiões Promotoras Genéticas , RNA Interferente Pequeno/química , RNA Interferente Pequeno/metabolismo , Replicação Viral
18.
Vet Anaesth Analg ; 38(4): 336-43, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21627758

RESUMO

OBJECTIVE: To investigate changes in colloid osmotic pressure (COP), total protein (TP) and osmolality (OSM) during anesthesia in horses given intravenous lactated Ringer's solution (LRS) or LRS and hetastarch (HES). STUDY DESIGN: Prospective, clinical trial. ANIMALS: Fourteen horses presented for surgery. Mean age 8.3 ± 1.9 years; mean weight 452 ± 25 kg. METHODS: Horses were premedicated with xylazine intravenously (IV); anesthesia was induced with ketamine and diazepam IV, and maintained with sevoflurane. Butorphanol was administered IV with pre-medications or immediately after induction. Xylazine was administered IV for recovery if necessary. LRS was administered IV to all horses with a target rate of 5-10 mL kg(-1) hour(-1). Half of the horses also received 6% HES, 2.5 mL kg(-1) over 1 hour in addition to LRS. Horses that received LRS only were considered the LRS group. Horses that received both LRS and HES were considered the LRS/HES group. Blood was drawn pre- and post-anesthesia, immediately following induction, and every 30 minutes throughout anesthesia. COP, TP and OSM were measured. RESULTS: COP and TP significantly decreased at similar rates for both treatment groups from pre-anesthetic values. Pre-anesthetic COP was significantly greater in the LRS group when compared to the LRS/HES group pre-, post- and throughout anesthesia. In the LRS group post-anesthetic OSM was significantly different than the pre-anesthesia value and that for the LRS/HES group. CONCLUSIONS AND CLINICAL RELEVANCE: Administration of IV HES (2.5 mL kg(-1), over 1 hour) in combination with LRS does not attenuate the decrease in COP typically seen during anesthesia with crystalloid administration alone. Based on these results, administration of HES at this rate and total volume would not be expected to prevent fluid shifts into the interstitium through its effects on COP.


Assuntos
Anestesia Geral/veterinária , Fenômenos Fisiológicos Sanguíneos/efeitos dos fármacos , Proteínas Sanguíneas/efeitos dos fármacos , Cavalos , Derivados de Hidroxietil Amido/farmacologia , Soluções Isotônicas/farmacologia , Animais , Proteínas Sanguíneas/análise , Coloides , Esquema de Medicação/veterinária , Derivados de Hidroxietil Amido/administração & dosagem , Infusões Intravenosas/veterinária , Soluções Isotônicas/administração & dosagem , Concentração Osmolar , Pressão Osmótica/efeitos dos fármacos , Estudos Prospectivos , Lactato de Ringer
19.
Vet Anaesth Analg ; 38(3): 267-71, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-21492393

RESUMO

OBJECTIVE: To describe the ultrasound-guided technique to the transversus abdominis plane (TAP) block in the dog and evaluate the spread of a local anesthetic/methylene blue solution. STUDY DESIGN: Prospective experimental trial. ANIMALS: Ten adult Beagle cadavers weighing 11.1 ± 1.1 kg (mean ± SD). METHODS: Transversus abdominis plane (TAP) blocks were performed bilaterally by a single trained individual on unpreserved cadaver dogs using 10 mL of methylene blue/bupivacaine solution per site. Dissection of the abdominal wall was performed within 15-55 minutes of block to determine distribution of injectate and nerve involvement in the transversus abdominis fascial plane. RESULTS: The transversus abdominis fascial plane was adequately visualized via ultrasound and injected in twenty hemi-abdominal walls. Segmental branches of T11, T12, T13, L1, L2, and L3 were adequately stained in 20%, 60%, 100%, 100%, 90%, and 30% of injections, respectively. CONCLUSIONS AND CLINICAL RELEVANCE: This anatomical study suggests that the transversus abdominis plane (TAP) block would provide adequate regional anesthesia of the abdomen, potentially extending to the cranial and caudal limits of the abdomen. This supports the clinical potential of this block in veterinary medicine.


Assuntos
Parede Abdominal/diagnóstico por imagem , Parede Abdominal/inervação , Anestésicos Locais/farmacocinética , Bupivacaína/farmacocinética , Cães/cirurgia , Bloqueio Nervoso/veterinária , Animais , Azul de Metileno/administração & dosagem , Azul de Metileno/farmacocinética , Bloqueio Nervoso/instrumentação , Bloqueio Nervoso/métodos , Estudos Prospectivos , Ultrassonografia
20.
Res Pract Thromb Haemost ; 4(5): 872-878, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32685897

RESUMO

BACKGROUND: Discharged medical patients are at risk for venous thromboembolism (VTE). It is difficult to identify which discharged patients would benefit from extended duration thromboprophylaxis. The Intermountain Risk Score is a prediction score derived from discrete components of the complete blood cell count and basic metabolic panel and is highly predictive of 1-year mortality. We sought to ascertain if the Intermountain Risk Score might also be predictive of 90-day postdischarge hospital-associated VTE (HA-VTE). METHODS: We applied the Intermountain Risk Score to 60 064 medical patients who survived 90 days after discharge and report predictiveness for HA-VTE. Area under the receiver operating curve analyses were performed. We then assessed whether the Intermountain Risk Score improved prediction of 2 existing VTE risk assessment models. RESULTS: The Intermountain Risk Score poorly predicted HA-VTE (area under the curve = 0.58; 95% confidence interval [CI], 0.56-0.60). Each clinical risk assessment model was superior to the Intermountain Risk Score (UTAH area under the curve, 0.63; Kucher area under the curve, 0.62; Intermountain Risk Score area under the curve, 0.58; P < .001 for each comparison). Adding the Intermountain Risk Score to these scores did not substantially improve the performance of either risk assessment model (UTAH + Intermountain Risk Score, 0.65; Kucher + Intermountain Risk Score, 0.64). CONCLUSION: The Intermountain Risk Score demonstrated poor predictiveness for HA-VTE when compared to existing risk assessment models. Adding the Intermountain Risk Score to existing risk assessment models did not improve upon either risk assessment model alone to justify the added complexity.

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