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1.
JCI Insight ; 2024 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-39088277

RESUMO

Rift Valley fever (RVF) is an emerging arboviral disease affecting both humans and livestock. In humans, RVF displays a spectrum of clinical manifestations, including encephalitis. To date, there are no FDA-approved vaccines or therapeutics for human use, although several are in pre-clinical development. Few small animal models of RVF encephalitis exist, further complicating countermeasure assessment. Human mAbs RVFV-140, RVFV-268 and RVFV-379 are recombinant potently neutralizing antibodies that prevent infection by binding the RVFV surface glycoproteins. Previous studies showed that both RVFV-268 and RVFV-140 improve survival in a lethal mouse model of disease, and RVFV-268 has prevented vertical transmission in a pregnant rat model of infection. Despite these successes, evaluation of mAbs in the context of brain disease has been limited. This is the first study to assess neutralizing antibodies for prevention of RVF neurologic disease using a rat model. Administration of RVFV-140, RVFV-268, or RVFV-379 twenty-four hours prior to aerosol exposure to the virulent ZH501 strain of RVFV results in substantially enhanced survival and lack of neurological signs of disease. These results using a stringent and highly lethal aerosol infection model supports the potential use of human mAbs to prevent the development of RVF encephalitis.

2.
J Neurosurg Spine ; : 1-9, 2024 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-39094190

RESUMO

OBJECTIVE: Prior studies investigating the use of minimally invasive transforaminal lumbar interbody fusion (MI-TLIF) for treatment of degenerative lumbar conditions and concomitant sagittal deformity have not stratified patients by preoperative pelvic incidence (PI)-lumbar lordosis (LL) mismatch, which is the earliest parameter to deteriorate in mild sagittal deformity. Thus, the aim of the present study was to determine the impact of preoperative PI-LL mismatch on clinical outcomes and sagittal balance restoration among patients undergoing MI-TLIF for degenerative spondylolisthesis (DS). METHODS: Consecutive adult patients undergoing primary 1-level MI-TLIF between April 2017 and April 2022 for DS with ≥ 6 months radiographic follow-up were included. Patient-reported outcome measures (PROMs) included the Oswestry Disability Index, visual analog scale (VAS), 12-Item Short-Form Health Survey (SF-12), and Patient-Reported Outcomes Measurement Information System at preoperative, early postoperative (< 6 months), and late postoperative (≥ 6 months) time points. The minimal clinically important difference (MCID) for PROMs was also evaluated. Radiographic parameters included PI, LL, pelvic tilt (PT), and sagittal vertical axis (SVA). Patients were categorized into balanced and unbalanced groups based on preoperative PI-LL mismatch according to age-adjusted alignment goals. Changes in radiographic parameters and PROMs were evaluated. RESULTS: Eighty patients were included (L4-5 82.5%, grade I spondylolisthesis 82.5%, unbalanced 58.8%). Mean clinical and radiographic follow-up were 17.0 and 8.3 months, respectively. The average preoperative PI-LL was 18.8° in the unbalanced group and -3.3° in the balanced group. Patients with preoperative PI-LL mismatch had significantly worse preoperative PT (26.2° vs 16.4°, p < 0.001) and SVA (53.2 vs 9.0 mm, p = 0.001) compared with balanced patients. Patients with preoperative PI-LL mismatch also showed significantly worse PI-LL (16.0° vs 0.54°, p < 0.001), PT (25.9° vs 18.7°, p < 0.001), and SVA (49.4 vs 22.8 mm, p = 0.013) at long-term follow-up. No significant radiographic improvement was observed among unbalanced patients. All patients demonstrated significant improvements in all PROMs (p < 0.05) except for SF-12 mental component score. Achievement of MCID for VAS back score was significantly greater among patients with preoperative PI-LL mismatch (85.7% vs 65.5%, p = 0.045). CONCLUSIONS: Although 1-level MI-TLIF did not restore sagittal alignment in patients with preoperative PI-LL mismatch, patients presenting with DS can expect significant improvement in PROMs following 1-level MI-TLIF regardless of preoperative alignment or extent of correction. Thus, attaining good clinical outcomes in patients with mild sagittal imbalance may not require addressing imbalance directly.

4.
J Phys Chem B ; 2024 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-39150518

RESUMO

CarH is a protein photoreceptor that uses a form of B12, adenosylcobalamin (AdoCbl), to sense light via formation of a metastable excited state. Aside from AdoCbl bound to CarH, methylcobalamin (MeCbl) is the only other example─to date─of photoexcited cobalamins forming metastable excited states with lifetimes of nanoseconds or longer. The UV-visible spectra of the excited states of MeCbl and AdoCbl bound to CarH are similar. We have used transient Co K-edge X-ray absorption and X-ray emission spectroscopies in conjunction with transient absorption spectroscopy in the UV-visible region to characterize the excited states of MeCbl. These data show that the metastable excited state of MeCbl has a slightly expanded corrin ring and increased electron density on the cobalt, but only small changes in the axial bond lengths.

5.
ACS Catal ; 14(6): 4362-4368, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-39157175

RESUMO

Herein, we report a three stranded coiled-coil (3SCC) de novo protein containing a type II copper center (CuT2) composed of 6-membered ring N-heterocycles. This design yields the most active homogenous copper nitrite reductase (CuNiR) mimic in water. We achieved this result by controlling three factors. First, previous studies with Nδ and Nε -Methyl Histidine had indicated that a ligand providing pyridine-like electronic character to the copper site was superior to the more donating Nδ for nitrite reduction. By substitution of the parent histidine with the non-coded amino acids pyridyl alanine (3'-Pyridine [3'Py] vs 4'-Pyridine [4'Py]), an authentic pyridine donor was employed without the complications of the coupling of both electronic and tautomeric effects of histidine or methylated histidine. Second, by changing the position of the nitrogen atom within the active site (4'-Pyridine vs. 3'Pyridine) a doubling of the enzyme's catalytic efficiency resulted. This effect was driven exclusivity by substrate binding to the copper site. Third, we replaced the leucine layer adjacent to the active site with an alanine, and the disparity between the 3'Py and 4'Py became more apparent. The decreased steric bulk minimally impacted the 3'Py derivative; however, the 4'Py K m decreased by an order of magnitude (600 mM to 50 mM), resulting in a 40-fold enhancement in the k cat/K m compared to the analogues histidine site and a 1500-fold improvement compared with the initially reported CuNiR catalyst of this family, TRIW-H. When combined with XANES/EXAFS data, the relaxing of the Cu(I) site to a more 2-coordinate Cu(I) like structure in the resting state increases the overall catalytic efficiency of nitrite reduction via the lowering of K m. This study illustrates how by combining advanced spectroscopic methods, detailed kinetic analysis, and a broad toolbox of amino acid side chain functionality, one can rationally design systems that optimize biomimetic catalysis.

6.
J Am Heart Assoc ; 13(16): e9983, 2024 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-39158572

RESUMO

BACKGROUND: Aortic regurgitation is distinguished by the backflow of blood from the aorta into the left ventricle. American College of Cardiology/American Heart Association guidelines recommend surgical aortic valve replacement (SAVR) for patients with symptomatic aortic regurgitation (sAR). This study estimates the difference in mortality, health care use, and costs between patients with sAR who receive SAVR within 12 months of diagnosis versus those who do not. METHODS AND RESULTS: We used the Optum United Healthcare database to identify 132 317 patients diagnosed with sAR from 2016 to 2021 who had at least 6 months of enrollment before sAR and 12 months of enrollment after. Criteria were no history of aortic stenosis or transcatheter aortic valve replacement and ≥2 visits for heart failure, angina, dyspnea, or syncope. Outcomes were all-cause mortality, health care use, and annualized cost. Baseline differences in demographics and comorbidities were adjusted with inverse propensity score weighting. We modeled survival and estimated health care use and costs using Cox proportional hazards and general linear models, respectively. Of the 132 317 patients, 400 underwent SAVR within 12 months of diagnosis. They were on average younger, more often men, and with a slightly higher Elixhauser Comorbidity Index score. After inverse propensity score weighting, patients with sAR who had SAVR had lower mortality, fewer inpatient and emergency department visits, fewer hospital days, and lower annualized cost. CONCLUSIONS: SAVR performed within 12 months of an sAR diagnosis is associated with improved mortality and lower annualized health care use and costs. These clinical and economic benefits should be considered when managing patients with sAR.


Assuntos
Insuficiência da Valva Aórtica , Implante de Prótese de Valva Cardíaca , Humanos , Masculino , Feminino , Insuficiência da Valva Aórtica/cirurgia , Insuficiência da Valva Aórtica/economia , Insuficiência da Valva Aórtica/mortalidade , Idoso , Implante de Prótese de Valva Cardíaca/economia , Implante de Prótese de Valva Cardíaca/efeitos adversos , Estados Unidos/epidemiologia , Pessoa de Meia-Idade , Estudos Retrospectivos , Idoso de 80 Anos ou mais , Valva Aórtica/cirurgia , Resultado do Tratamento , Análise Custo-Benefício , Custos de Cuidados de Saúde/estatística & dados numéricos , Fatores de Tempo , Bases de Dados Factuais
7.
PLoS One ; 19(8): e0308999, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39159176

RESUMO

Heart failure (HF) with reduced ejection fraction (HFrEF) is a risk factor for drug-induced QT interval prolongation. It is unknown if HF with preserved ejection fraction (HFpEF) is also associated with an increased risk. Dofetilide and sotalol are potent QT interval-prolonging agents that are frequently used in patients with HFpEF, in whom atrial fibrillation is a common comorbidity. We tested the hypothesis that the risk of QT interval prolongation associated with dofetilide and sotalol is increased in patients with HFpEF. We conducted a retrospective cohort study conducted using electronic health records from the Indiana Network for Patient Care (January 31, 2010 -May 3, 2021). After removing patients with overlapping diagnoses of HFpEF and HFrEF, no diagnosis code, and absence of QT interval records, we identified patients taking dofetilide or sotalol among three groups: HFrEF (n = 138), HFpEF (n = 109), and no HF (n = 729). QT prolongation was defined as heart rate-corrected QT (QTc) > 500 ms during dofetilide/sotalol therapy. Unadjusted odds ratios (OR) for QT prolongation were determined by univariate analysis. Adjusted ORs were determined by generalized estimating equations (GEE) with logit link to account for an individual cluster with different times of hospitalization and covariates. QTc prolongation associated with dofetilide or sotalol occurred in 53.2%, 71.7% and 30.0% of patients with HFpEF, HFrEF, and patients with no HF, respectively. After adjusting for age, sex, race, serum potassium and magnesium concentrations, kidney function, concomitant drug therapy, and comorbid conditions, the adjusted odds of QTc prolongation were significantly higher in patients with HFpEF [OR = 1.98 (95% CI 1.17-3.33)], and in those with HFrEF [OR = 5.23, (3.15-8.67)], compared to those with no evidence of HF. The odds of QT prolongation among inpatients receiving dofetilide or sotalol were increased in patients with HFpEF and HFrEF compared to those who did not have HF.


Assuntos
Insuficiência Cardíaca , Síndrome do QT Longo , Fenetilaminas , Sotalol , Volume Sistólico , Sulfonamidas , Humanos , Insuficiência Cardíaca/fisiopatologia , Insuficiência Cardíaca/tratamento farmacológico , Feminino , Masculino , Idoso , Fenetilaminas/efeitos adversos , Sotalol/efeitos adversos , Volume Sistólico/efeitos dos fármacos , Estudos Retrospectivos , Sulfonamidas/efeitos adversos , Síndrome do QT Longo/induzido quimicamente , Síndrome do QT Longo/fisiopatologia , Síndrome do QT Longo/epidemiologia , Pessoa de Meia-Idade , Idoso de 80 Anos ou mais , Eletrocardiografia , Antiarrítmicos/efeitos adversos , Fatores de Risco
8.
J Mater Chem B ; 2024 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-39176566

RESUMO

Mosquito-borne diseases are responsible for 700 000 deaths annually. Current outdoor protective strategies primarily focus on direct skin application of commercial repellents (i.e., aerosol sprays or topical lotions) which are typically limited to efficacy times of ≤10 hours due to rapid evaporation and dermal absorption. Consequently, frequent reapplication for continuous protection can increase associated health hazards and cause noncompliance. This study utilizes Hansen solubility parameter modeling to design physical gels composed of insect-repelling N,N-diethyl-meta-toluamide (DEET) and modacrylic copolymer poly(acrylonitrile-co-vinyl chloride) (P(AN-VC)). The P(AN-VC)/DEET composites exhibit tunable and reversible sol-gel transition temperatures that can meet the thermomechanical stability demands of the intended application and permit facile transition to commercial melt processing techniques such as injection molding, filament spinning, or film casting. P(AN-VC)/DEET gel films demonstrate mosquito repellency for more than half a year-performing longer than any other known material to date-due to the high reservoir of repellent and its desorption hindrance from the polymer matrix. Therefore, P(AN-VC)/DEET gels hold significant potential for extended protection against mosquitos and other biting arthropods.

9.
Pharmacol Biochem Behav ; : 173858, 2024 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-39178918

RESUMO

Anxiety is a part of the human condition and has been managed by psychoactive substances for centuries. The current medical need and societal demand for anxiolytic medicines has not abated. The present overview provides a brief historical introduction to the discovery of modern age anxiolytics that include the benzodiazepines together with a discussion of the continuing medical need for new antianxiety medications. The paper also discusses the use and impact of behavioral pharmacology in the preclinical development of anxiolytics. The review then highlights the diversity of mechanisms for creating a new generation of anxioltyics through mechanisms beyond the potentiation of GABAA receptors and the blockade of monoamine uptake. A discussion then follows on the behavioral specificity of action of anxiolytics that includes the concept of creating an anxioselective drug, one that targets anxiety without producing untoward effects that include sedation and dependence. The use of anxiolytics in the treatment of other conditions such as substance use disorder is also briefly reviewed. Finally, a brief summary of the current status of anxiolytic drug development is provided. The review concludes with the idea that despite a host of anxiolytic drugs, the lack of efficacy in some patients and the side-effects and safety issues associated with some of these medications demands alternative medicines. Current preclinical and clinical research is ongoing with the goal of identifying such compounds.

10.
EJHaem ; 5(4): 784-788, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-39157618

RESUMO

Congenital enterovirus infection can be associated with a pro-inflammatory state triggering haemophagocytic lymphohistiocytosis (HLH). Enteroviruses are also known to cause transient neutropenia in healthy children. Two infants presented with temperature instability, lethargy, thrombocytopaenia, hepatosplenomegaly and evidence of hyperinflammation in the setting of perinatal maternal rash and household contacts with gastrointestinal symptoms. Whilst HLH was successfully treated in both, protracted neutropenia persisted. Immune dysregulation with enterovirus in the neonatal period can provoke the generation of autoantibodies to hematologic cells giving rise to conditions such as autoimmune neutropenia. Sustained neutropaenia, after resolution of secondary infectious forms of HLH, requires investigation for underlying aetiologies.

11.
Glob Chang Biol ; 30(8): e17482, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-39189596

RESUMO

Rising global temperatures are often identified as the key driver impacting ecosystems and the services they provide by affecting biodiversity structure and function. A disproportionate amount of our understanding of biodiversity and function is from short-term experimental studies and static values of biodiversity indices, lacking the ability to monitor long-term trends and capture community dynamics. Here, we analyse a biennial dataset spanning 32 years of macroinvertebrate benthic communities and their functional response to increasing temperatures. We monitored changes in species' thermal affinities to examine warming-related shifts by selecting their mid-point global temperature distribution range and linking them to species' traits. We employed a novel weighted metric using Biological Trait Analysis (BTA) to gain better insights into the ecological potential of each species by incorporating species abundance and body size and selecting a subset of traits that represent five ecosystem functions: bioturbation activity, sediment stability, nutrient recycling and higher and lower trophic production. Using biodiversity indices (richness, Simpson's diversity and vulnerability) and functional indices (richness, Rao's Q and redundancy), the community structure showed no significant change over time with a narrow range of variation. However, we show shifts in species composition with warming and increases in the abundance of individuals, which altered ecosystem functioning positively and/or non-linearly. Yet, when higher taxonomic groupings than species were excluded from the analysis, there was only a weak increase in the measured change in community-weighted average thermal affinities, suggesting changes in ecosystem functions over time occur independently of temperature increase-related shifts in community composition. Other environmental factors driving species composition and abundance may be more important in these subtidal macrobenthic communities. This challenges the prevailing emphasis on temperature as the primary driver of ecological response to climate change and emphasises the necessity for a comprehensive understanding of the temporal dynamics of complex systems.


Assuntos
Biodiversidade , Ecossistema , Invertebrados , Temperatura , Animais , Invertebrados/fisiologia , Mudança Climática , Aquecimento Global
12.
J Am Heart Assoc ; : e031461, 2024 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-39189613

RESUMO

BACKGROUND: The treatment of severe aortic stenosis has evolved considerably since the introduction of transcatheter aortic valve replacement (TAVR), yet trends in complications for patients undergoing TAVR or surgical aortic valve replacement (SAVR) at a national level have yet to be evaluated. METHODS AND RESULTS: We performed a retrospective cohort study using Medicare data to evaluate temporal trends in complications among beneficiaries, aged ≥65 years, treated with elective isolated transfemoral TAVR or SAVR between 2012 and 2019. The study end point was the occurrence of a major complication (composite outcome) during index and up to 30 days after. Multivariable logistic regression was used to assess odds of complications for TAVR and SAVR, individually over time, and for TAVR versus SAVR, over time. The cohort included 211 212 patients (mean±SD age, 78.6±7.3 years; 45.0% women). Complication rates during index following elective isolated aortic valve replacement decreased from 49% in 2012 to 22% in 2019. These reductions were more pronounced for TAVR (41% to >19%, Δ=22%) than SAVR (51% to >47%, Δ=4%). After risk adjustment, the risk of any complication with TAVR was 47% (P<0.0001) lower compared with SAVR in 2012, and 78% (P<0.0001) lower in 2019. TAVR was independently associated with reduced odds of complications each year compared with 2012, with the magnitude of benefit increasing over time (2013 versus 2012: odds ratio [OR], 0.89 [95% CI, 0.81-0.97]; 2019 versus 2012: OR, 0.35 [95% CI, 0.33-0.38]). These findings are consistent for complications up to 30 days from index. CONCLUSIONS: Between 2012 and 2019, the risk of complications after aortic valve replacement among Medicare beneficiaries decreased significantly, with larger absolute and relative changes among patients treated with TAVR than SAVR.

13.
Radiology ; 312(2): e233041, 2024 08.
Artigo em Inglês | MEDLINE | ID: mdl-39105645

RESUMO

Background The combination of intravenous thrombolysis (IVT) with mechanical thrombectomy (MT) may have clinical benefits for patients with medium vessel occlusion. Purpose To examine whether MT combined with IVT is associated with different outcomes than MT alone in patients with acute ischemic stroke (AIS) and medium vessel occlusion. Materials and Methods This retrospective study included consecutive adult patients with AIS and medium vessel occlusion treated with MT or MT with IVT at 37 academic centers in North America, Asia, and Europe. Data were collected from September 2017 to July 2021. Propensity score matching was performed to reduce confounding. Univariable and multivariable logistic regression analyses were performed to test the association between the addition of IVT treatment and different functional and safety outcomes. Results After propensity score matching, 670 patients (median age, 75 years [IQR, 64-82 years]; 356 female) were included in the analysis; 335 underwent MT alone and 335 underwent MT with IVT. Median onset to puncture (350 vs 210 minutes, P < .001) and onset to recanalization (397 vs 273 minutes, P < .001) times were higher in the MT group than the MT with IVT group, respectively. In the univariable regression analysis, the addition of IVT was associated with higher odds of a modified Rankin Scale (mRS) score 0-2 (odds ratio [OR], 1.44; 95% CI: 1.06, 1.96; P = .019); however, this association was not observed in the multivariable analysis (OR, 1.37; 95% CI: 0.99, 1.89; P = .054). In the multivariable analysis, the addition of IVT also showed no evidence of an association with the odds of first-pass effect (OR, 1.27; 95% CI: 0.9, 1.79; P = .17), Thrombolysis in Cerebral Infarction grades 2b-3 (OR, 1.64; 95% CI: 0.99, 2.73; P = .055), mRS scores 0-1 (OR, 1.27; 95% CI: 0.91, 1.76; P = .16), mortality (OR, 0.78; 95% CI: 0.49, 1.24; P = .29), or intracranial hemorrhage (OR, 1.25; 95% CI: 0.88, 1.76; P = .21). Conclusion Adjunctive IVT may not provide benefit to MT in patients with AIS caused by distal and medium vessel occlusion. © RSNA, 2024 Supplemental material is available for this article. See also the editorial by Wojak in this issue.


Assuntos
AVC Isquêmico , Trombectomia , Terapia Trombolítica , Humanos , Feminino , Masculino , Idoso , Estudos Retrospectivos , Trombectomia/métodos , AVC Isquêmico/diagnóstico por imagem , AVC Isquêmico/cirurgia , AVC Isquêmico/terapia , Pessoa de Meia-Idade , Idoso de 80 Anos ou mais , Terapia Trombolítica/métodos , Terapia Combinada , Resultado do Tratamento , Fibrinolíticos/uso terapêutico , Fibrinolíticos/administração & dosagem , Pontuação de Propensão
15.
J Am Acad Dermatol ; 2024 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-39182687

RESUMO

BACKGROUND: Childhood cancer survivors (CCS) are at increased risk for keratinocyte carcinomas (KC) however, the long-term incidence of single and multiple KC is not well established. OBJECTIVE: Identify risk factors and quantify KC cumulative incidence and multiple-incidence burden in CCS. METHODS: KC were identified among Childhood Cancer Survivor Study participants, a cohort of five-year cancer survivors diagnosed <21 years of age between 1970-1999 in North America. Cumulative incidence was estimated, and multivariable models assessed relative rates of KC associated with survivor and treatment characteristics. RESULTS: Among 25,658 participants, 1,446 developed 5,363 KC (93.5% basal cell carcinoma, 6.7% squamous cell carcinoma; mean age 37.0 years (range 7.3-67.4), mean latency 25.7 years; 95.3% White and 88.4% with radiotherapy [RT]). Mean lesion count was 3.7 with 26.1% experiencing ≥4. RT imparted a 4.5-fold increase in the rate of any KC and 9.4-fold increase in the rate of ≥4 KC. Allogeneic and autologous hematopoietic cell transplant were associated with a 3.4- and 2.3-fold increased rate of KC, respectively. LIMITATIONS: Participant self-reporting of some data including race without skin phototype and past medical history may have impacted analysis. CONCLUSIONS: The burden of KC in CCS remains high, but predictable risk factors should guide screening.

16.
Ecol Appl ; : e3016, 2024 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-39138827

RESUMO

Understanding the relationship between a dam's size and its ecological effects is important for prioritization of river restoration efforts based on dam removal. Although much is known about the effects of large storage dams, this information may not be applicable to small dams, which represent the vast majority of dams being considered for removal. To better understand how dam effects vary with size, we conducted a multidisciplinary study of the downstream effect of dams on a range of ecological characteristics including geomorphology, water chemistry, periphyton, riparian vegetation, benthic macroinvertebrates, and fish. We related dam size variables to the downstream-upstream fractional difference in measured ecological characteristics for 16 dams in the mid-Atlantic region ranging from 0.9 to 57 m high, with hydraulic residence times (HRTs) ranging from 30 min to 1.5 years. For a range of physical attributes, larger dams had larger effects. For example, the water surface width below dams was greater below large dams. By contrast, there was no effect of dam size on sediment grain size, though the fraction of fine-grained bed material was lower below dams independently of dam size. Larger dams tended to reduce water quality more, with decreased downstream dissolved oxygen and increased temperature. Larger dams decreased inorganic nutrients (N, P, Si), but increased particulate nutrients (N, P) in downstream reaches. Aquatic organisms tended to have greater dissimilarity in species composition below larger dams (for fish and periphyton), lower taxonomic diversity (for macroinvertebrates), and greater pollution tolerance (for periphyton and macroinvertebrates). Plants responded differently below large and small dams, with fewer invasive species below large dams, but more below small dams. Overall, these results demonstrate that larger dams have much greater impact on the ecosystem components we measured, and hence their removal has the greatest potential for restoring river ecosystems.

17.
J Surg Oncol ; 2024 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-39138920

RESUMO

BACKGROUND: Variations of hand and forearm lymphatic drainage to upper-arm lymphatic pathways may impact the route of melanoma metastasis. This study compared rates of lymphatic drainage to epitrochlear nodes between anatomic divisions of the hand and forearm to determine whether the anatomic distribution of hand and forearm melanomas affects the likelihood of drainage to epitrochlear lymph nodes. METHODS: Using a single-institution lymphoscintigraphy database, we identified all patients with cutaneous melanoma on the hand and forearm. A body-map two-dimensional coordinate system was used to classify cutaneous melanoma sites between radial-ulnar and dorsal-volar divisions. Sentinel lymph nodes (SLNs) visualized on lymphoscintigraphy were recorded. Proportions of patients with epitrochlear SLNs were compared between anatomic divisions using χ2 analysis. RESULTS: Of 3628 upper extremity cutaneous melanoma patients who underwent lymphatic mapping with lymphoscintigraphy, 1400 met inclusion criteria. Twenty-one percent of patients demonstrated epitrochlear SLNs. Epitrochlear SLNs were observed in 27% of dorsal forearm melanomas and 15% of volar forearm melanomas (p < 0.001). Epitrochlear SLNs were observed in 31% of ulnar forearm melanomas and 17% of radial forearm melanomas (p < 0.001). CONCLUSIONS: Higher proportions of dorsal and ulnar forearm melanomas have epitrochlear SLNs. Metastasis to epitrochlear SLNs may be more likely from melanomas in these respective forearm regions.

18.
Artigo em Inglês | MEDLINE | ID: mdl-39126285

RESUMO

OBJECTIVE: Sternal wound infection (SWI) is a rare but potentially life-threatening complication in children following sternotomy. Risk factors include young age, extended preoperative hospitalization, and prolonged ventilatory support. Few studies have explored the impact of pre-existing tracheostomy on SWI in pediatric patients. The purpose of this study is to measure the effect of tracheostomy and other factors on SWI in children undergoing sternotomy. STUDY DESIGN: Retrospective cohort study of a 12 year period. SETTING: Tertiary children's hospital. METHODS: Children with a tracheostomy prior to sternotomy (TPS) were identified and matched by age, height, and weight to children who underwent sternotomy alone. Demographics, medical comorbidities, surgical details, SWI diagnosis and management information, and surgical outcomes were collected. RESULTS: We identified 60 unique individuals representing 80 sternotomies. The incidence of SWI was 22.5% (n = 9) in children with a tracheostomy and 2.5% (n = 1) in those without. The incidence of SWI was greater in children with a tracheostomy (90% vs 10% in those without, P = .007) and underlying pulmonary disease (90% vs 10% in those without, P = .020). Infections in the TPS group also demonstrated greater frequency of Pseudomonas aeruginosa (n = 3) and polymicrobial growth (n = 2). CONCLUSION: The risk of developing a SWI in children undergoing sternotomy is significantly greater in those with a tracheostomy and underlying pulmonary disease. Further study is needed to understand other contributing factors and ways to mitigate this risk.

19.
Am J Vet Res ; : 1-9, 2024 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-39116915

RESUMO

OBJECTIVE: The purpose of this study was to compare various sampling techniques and commercially available diagnostic tests for Cryptosporidium serpentis. METHODS: A colony of 80 eastern indigo snakes (Drymarchon couperi) in human care was screened for the presence of C serpentis using endoscopic gastric mucosal biopsies for histologic and molecular analyses. At the time of endoscopic examination and biopsy, a cloacal swab, gastric swab, and gastric lavage sample were also collected. A C serpentis-specific probe hybridization quantitative PCR (qPCR) was performed on each sample. The gastric lavage sample was divided equally for direct microscopy, acid-fast stain, rapid qualitative immunochromatographic assay, direct fluorescent antibody, and 5 different PCR analyses. If a fecal sample was available at the time of endoscopic evaluation, it was also evaluated for Cryptosporidium oocysts by direct microscopy and acid-fast staining. RESULTS: When comparing test results to histologic analyses, the sensitivity of the probe hybridization qPCR of gastric biopsy, gastric lavage, and gastric swab was 100% while the cloacal swab was 72%. When gastric lavage tests were compared, qPCRs outperformed the other tests. CONCLUSIONS: Endoscopic biopsy for histologic and qPCR analyses is recommended for disease diagnosis, while gastric lavage or gastric swab samples for qPCR analysis are as sensitive as endoscopic biopsy for screening for the pathogen but cannot diagnose disease. CLINICAL RELEVANCE: The results from this study allow the veterinary practitioner to select the most appropriate sample and testing methodology when evaluating an ophidian patient for gastric cryptosporidiosis.

20.
Appl Spectrosc ; : 37028241268260, 2024 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-39091031

RESUMO

Nondispersive ultraviolet visible gas analyzer designs were evaluated for monitoring molybdenum-containing chloride and oxychloride precursor delivery during microelectronics vapor deposition processes. The performances of three analyzer designs, which differed only in the bandpass filter employed for wavelength selection, were compared for measuring the partial pressure of molybdenum pentachloride, molybdenum oxytetrachloride (MoOCl4), and molybdenum dioxydichloride (MoO2Cl2). The analyzer's optical response with a 369 nm center wavelength filter for molybdenum pentachloride was determined by measuring the molybdenum pentachloride absorbance as a function of vapor molar density. The calibrated analyzer was transferred to a process line on a deposition chamber and used to measure the molybdenum pentachloride partial pressure during delivery in a flowing carrier gas. The molybdenum pentachloride minimum detectable density was determined to be 1 × 10-4 mol m-3 (0.35 Pa for a cell temperature of 145 °C), for data collected at 1 kHz and referenced to a 0.2 s duration background. The analyzer optical response for molybdenum pentachloride with the two other filters and the response for MoOCl4 and MoO2Cl2 with all three filters were simulated with a simple model. These data were used to evaluate the sensitivity and selectivity of analyzers incorporating the different filters to some likely combinations of analytes and interferents.

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