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1.
This article reviews the mechanisms of pulmonary injury associated with hydrocarbon poisoning. The evolution of clinical and radiographic changes is discussed, along with appropriate treatment. Preventing aspiration in the emergency department is the most effective therapy for these children in the first few hours after ingestion.  相似文献   
2.
BackgroundPrior studies have demonstrated declines in androgen levels in men with cancer and patients undergoing anesthesia and surgery. In this study, we hypothesized that decreased serum androgen levels are prevalent in male patients undergoing radical cystectomy (RC) for bladder cancer and that it persists in the postoperative period. We characterized perioperative androgen hormonal profiles and examined for associated changes indicative of sarcopenia on computed tomography scans in men undergoing RC.MethodsWe implemented a prospective observational trial in men with newly diagnosed non-metastatic bladder cancer undergoing RC. Baseline pre-operative total testosterone (TT), free testosterone (FT), and luteinizing hormone (LH) were obtained on morning lab draws with 30 days of surgery. TT and FT were then repeated on postoperative days (POD) 2, 3, 30, and 90. The threshold for normal TT was defined as >300 ng/dl, consistent with the AUA Guidelines for Evaluation and Management of Testosterone Deficiency. We evaluated postoperative changes in weight and psoas muscle cross-sectional area using computed tomography scans to assess for sarcopenic changes.ResultsUnivariable statistical analysis was performed. 25 patients were enrolled. The mean patient age was 68.9 years. The mean pre-operative TT was 308 ng/dl, and 12/23 (52.5%) patients had low testosterone. Mean TT onPOD 2 and 3 were 166 ng/dl and 161 ng/dl, respectively (range 24–345). 19/20 (95%) of men who had morning lab draws had decreased TT. The mean TT at 30 days was 253 ng/dl with 37.5% of men having low TT. Mean TT at 90 days was 306 ng/dl. The mean FT levels were 43 ng/dl, 29.25 ng/dl, 28.2 ng/dl, 40.89 ng/dl, and 42.62 ng/dl at baseline, POD 2, POD 3, POD 30, and POD 90, respectively. Mean LH at baseline was 9.9 IU/L. Average weight loss at 30- and 90- days postop was -4.29 and -4.38 kilograms, respectively. Weight loss was persistent with only 3/23 (13%) returning to their presurgery weight by 90 days. Despite significant declines in weight and perioperative TT, no significant differences in psoas muscle cross-sectional area were observed (net change -92 mm2, P= 0.13)ConclusionsPerioperative disruption of androgen levels is prevalent in men undergoing RC. Our trial demonstrates a pre-op, immediate postop, 30- and 90-day postoperative prevalence of low TT of 52%, 95%, 63%, and 37.5%, respectively. Significant changes in baseline weight were noted, although no significant changes in psoas muscle cross-sectional area were observed, limiting conclusions regarding a link between changes in androgens and sarcopenia in this setting.  相似文献   
3.
New treatments, particularly second‐line options, are needed to improve outcomes for patients with recurrent/metastatic cervical cancer (r/mCC). Tisotumab vedotin (TV) is an antibody–drug conjugate directed to tissue factor, a transmembrane protein commonly expressed in cancer cells, to deliver cytotoxic monomethyl auristatin E. This single‐arm, open‐label phase 1/2 trial evaluated the consistency of safety and efficacy outcomes of TV in Japanese patients with r/mCC to bridge the current findings with those reported in previous trials in non‐Japanese patients in the United States and Europe. In part 1 (dose escalation; N = 6), patients with advanced solid tumors received TV 1.5 or 2.0 mg/kg once every 3 weeks to determine the maximum tolerated dose (MTD) and recommended phase 2 dose (RP2D). Part 2 (dose expansion; N = 17) evaluated the RP2D in r/mCC patients with 1–2 prior lines of therapy. In part 1, no dose‐limiting toxicities were observed, the MTD was not reached, and TV 2.0 mg/kg was established as the RP2D. In part 2, the most common treatment‐emergent adverse events were anemia (58.8%), nausea (58.8%), alopecia (47.1%), epistaxis (47.1%), and diarrhea (35.3%); adverse events of special interest were bleeding (76.5%), ocular events (35.3%), and peripheral neuropathy (17.6%), and were mostly grade 1/2. In part 2, confirmed objective response rate was 29.4%, median duration of response was 7.1 months, and median time to response was 1.2 months. In Japanese patients with r/mCC, TV demonstrated a manageable and tolerable safety, pharmacokinetics, and efficacy profile consistent with that observed in non‐Japanese patients.  相似文献   
4.
Purpose: The biological consequences of initial physicochemical events following exposure of DNA to germicidal (254 nm) ultraviolet C (UV-C) radiation are not fully understood despite progress that has been made. In particular the cause of UV-C induced single strand breaks is not known. This question has been addressed in the present investigation.

Materials and methods: A plasmid construct, pMTa4, was exposed to UV-C in vitro as well as in vivo after transforming the plasmid into a repair proficient wild type and repair deficient, recF, mutant of E. coli. Following UV exposure in vivo, the plasmid was isolated under repair non-permissive and permissive conditions. The plasmid isolate and the pure super-coiled closed circular (CC) topological form of the plasmid were analyzed by agarose gel electrophoresis. The dependence of UV-C induced damage and conformational changes on the dose of radiation as well as on the duration of post-irradiation repair incubations was observed. The influence of UV-C on hyperchromic change and intercalation of ethidium bromide into plasmid DNA were also recorded.

Results: UV-C exposure of pMTa4 DNA in vitro and in vivo induced dose dependent, but sparsely placed, single strand breaks (SSB). While the wild type (AB1157) E. coli was able to repair SSB nearly completely under repair permissive condition, the recF (JC9239) mutant failed to do so. A dose-dependent relaxation of super-structure of CC form of pMTa4 DNA concomitant with enhanced ethidium bromide intercalation into the plasmid DNA was observed.

Conclusion: It is proposed that the conformational relaxation generated negative super-coiling strain on the DNA backbone of CC form of plasmid as well as exposed chemical bonds for hydrolytic cleavage. This might be the cause of the production of sparsely placed single strand breaks in pMTa4 upon exposure to low doses of UV-C.  相似文献   
5.
The endosomal Toll-like receptors (TLRs) TLR3, TLR7, TLR8 and TLR9 are important in sensing foreign nucleic acids encountered by phagocytes. Because TLR8 was initially thought to be non-functional in mice, less is known about TLR8 than the genetically and functionally related TLR7. Originally associated with the recognition of single-stranded RNA of viral origin, there is now evidence that human TLR8 is also able to sense bacterial RNA released within phagosomal vacuoles, inducing the production of both nuclear factor (NF)-κB-dependent cytokines and type I interferons (IFNs), such as IFN-β. The functions of TLR8 extend beyond the recognition of foreign pathogens and include cross-talk with other endosomal TLRs, a process that may also have a role in the generation of autoimmunity.  相似文献   
6.
The etiology for the majority of congenital heart defects (CHD) is unknown. We identified a patient with unbalanced atrioventricular septal defect (AVSD) and hypoplastic left ventricle who harbored an ~0.3 Mb monoallelic deletion on chromosome 3p14.1. The deletion encompassed the first four exons of FOXP1, a gene critical for normal heart development that represses cardiomyocyte proliferation and expression of Nkx2.5. To determine whether FOXP1 mutations are found in patients with CHD, we sequenced FOXP1 in 82 patients with AVSD or hypoplastic left heart syndrome. We discovered two patients who harbored a heterozygous c.1702C>T variant in FOXP1 that predicted a potentially deleterious substitution of a highly conserved proline (p.Pro568Ser). This variant was not found in 287 controls but is present in dbSNP at a 0.2% frequency. The orthologous murine Foxp1 p.Pro596Ser mutant protein displayed deficits in luciferase reporter assays and resulted in increased proliferation and Nkx2.5 expression in cardiomyoblasts. Our data suggest that haploinsufficiency of FOXP1 is associated with human CHD.  相似文献   
7.
A potential issue in current nerve guides is that they do not transmit electrical nerve impulses between the distal and proximal end of an injured nerve, i.e. a synapse. Conductivity is a desirable property of an ideal nerve guide that is being considered for peripheral nerve regeneration. Most conductive polymers reported for the fabrication of tissue engineering scaffolds, such as polypyrrole and polyaniline, are non-biodegradable and possess weak mechanical properties, and thus cannot be fabricated into 3D structures. Herein, we have designed a new nanocomposite material composed of dopamine, carbon nanofibers (CNF) and polycaprolactone (PCL) for the fabrication of nerve conduits, which facilitates the growth and migration of neurons toward the targeted end of an injured nerve. This support and navigation of the scaffold leads to better sensory and motor function. The results showed that the mechanical properties of the printed PCL increased by 30% in comparison with the pure PCL film, which is comparable with human nerves. The in vitro cell study of human glioma cells showed that the printed lines provided support for neural cell attachment, migration and differentiation toward the targeted end. In contrast, in the absence of printed lines in the scaffold, the cells attach and grow in random directions, forming a flower shape (cell cluster) on the surface of PCL. Thus, the proposed scaffold is a promising candidate for nerve guide application based on its signal transmission and navigating neurons in a correct pathway towards the targeted end.

Directional growth induced by dopamine-functionalized CNF-based nanocomposite ink printing.  相似文献   
8.

Background

Perinatal asphyxia is known to precipitate myocardial dysfunction, rhythm abnormalities and congestive cardiac failure.

Case characteristics

A 2-day old neonate with perinatal asphyxia.

Observation

He developed shock secondary to ventricular tachycardia, and required synchronized cardioversion for reversion of abnormal rhythm.

Outcome

Reversal of arrhythmia leading to recovery.

Message

Early identification and management of ventricular tachycardia in neonate with perinatal asphyxia can be lifesaving.  相似文献   
9.
10.
Encephalocele is protrusion of brain parenchyma through a defect in the cranium. It is classified into various types based on the defect location: sincipital (fronto-ethmoidal), basal (trans-sphenoidal, spheno-ethmoidal, trans-ethmoidal, and spheno-orbital), occipital and parietal. Double encephaloceles are very rare with only a handful of cases reported in the literature and most of these cases involved either occipital or sub-occipital region. All, except one, cases of double encephaloceles were diagnosed postnatally. We present a case of double encephalocele with parietal and occipital components diagnosed in utero. To the best of our knowledge, this is the first case of double encephalocele involving the parietal and occipital skull bones diagnosed in-utero.  相似文献   
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