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Parabens are antimicrobial additives found in a wide array of consumer products. However, the halogenated compounds formed from parabens during wastewater disinfection are a potential environmental concern. In order to identify these transformation products and investigate their mechanism of formation, a synthetic route to ethyl parabens labeled with the stable isotope carbon-13 at specific positions within the benzene ring was developed. This efficient two-step procedure starts from commercially available 13C-labeled phenols and involves (1) initial acylation of the phenol via a Houben–Hoesch reaction with trichloroacetonitrile followed by (2) a modified haloform reaction of the resulting trichloromethyl ketone to afford the corresponding 13C-labeled ethyl parabens in 65%–80% overall yield. The scope of the modified haloform reaction was also investigated, allowing for the synthesis of other parabens derived from primary or secondary alcohols, including 13C- and deuterium-labeled esters. In addition, 4-hydroxybenzoic acid can be formed directly from the common trichloromethyl ketone intermediate upon treatment with lithium hydroxide. This protocol complements existing methods for preparing 13C-labeled paraben derivatives and offers the specific advantages of exhibiting complete regioselectivity in the Houben–Hoesch reaction (to form the para-disubstituted product) and avoiding the need for protecting groups in the modified haloform reaction that forms the paraben esters.  相似文献   
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Background

The clinical experience of ceftaroline fosamil (CPT-F) therapy for Gram-positive infective endocarditis is reported from CAPTURE, a retrospective study conducted in the USA.

Methods

Data, including patient demographics, medical history, risk factors, microbiological aetiology and clinical outcomes, were collected by review of patient charts between September 2013 and February 2015.

Results

Patients (n=55) with Gram-positive endocarditis were treated with CPT-F. The most common risk factors were intravascular devices (43.6%), diabetes mellitus (40.0%) and injection drug use (38.2%). The most commonly isolated pathogens were meticillin-resistant Staphylococcus aureus (MRSA; 80%), meticillin-susceptible S. aureus (MSSA; 7.3%) and coagulase-negative staphylococci (7.3%). CPT-F was given as first-line therapy in 7.3% of patients and as second-line or later therapy in 92.7% of patients, and as monotherapy in 41.8% of patients and as concurrent therapy in 58.2% of patients. Clinical success was observed in 82.6% (19/23) of patients treated with CPT-F as monotherapy. In patients treated with CPT-F as first-line therapy or second-line or later therapy, 75.0% (3/4) and 70.6% (36/51) achieved success, respectively. Clinical success was observed in 77.3% (34/44) of patients with MRSA and 25% (1/4) of patients with MSSA. Two patients discontinued treatment with CPT-F due to an adverse event.

Conclusions

CPT-F treatment was associated with a high rate of clinical success in patients with Gram-positive infective endocarditis, including those with risk factors and infections caused by MRSA. A high rate of clinical success was observed in patients treated with CPT-F used as first- line therapy or second-line or later therapy, or as monotherapy or in combination with other antibiotics.  相似文献   
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Nine wrists in eight patients were treated surgically between 1988 and 2003 for symptomatic Madelung's deformity. The pain of involved wrist followed by forearm deformation fulfilled criteria for surgery. Closing wedge osteotomy of the distal radius were carried out eight times accompanied by shortening of the ulna (four patients), excision of the distal ulna (one patient), and no ulnar surgery (three patients). Pain relieved after surgery. The follow up period ranged from 1 to 9.5 years. No pour results were stated in subjective patient's estimation during final check up. Wrist appearance were stated to be satisfactory. Limitation of the range of motion concerning supination and pronation of the forearm were stated invariably. X-ray retrospective assessment of the inclination angle, lunate coverage and presence of arthritic changes were conducted. Time and method of surgical treatment for Madelung's deformity should be considered individually.  相似文献   
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This study examined the impact of childhood traumatic brain injury (TBI) on self-regulation and social and behavioral functioning, and the role of self-regulation as a predictor of children's social and behavioral functioning. Participants included 65 children with moderate to severe TBI and 65 children without TBI, all between 6 and 11 years of age. Self-regulation and social and behavioral functioning were assessed 2 to 5 years following injury. Children with TBI displayed deficits in self-regulation and social and behavioral functioning, after controlling for socioeconomic status (SES), although the magnitude of the deficits was not related to injury severity. Self-regulation accounted for significant variance in children's social and behavioral functioning, after controlling for SES and group membership. Self-regulation may be an important determinant of children's social and behavioral functioning following TBI.  相似文献   
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