光学活性的α-甲基丁酰基间苯三酚类化合物绝对构型与旋光方向的关系及其合成

合成了14个新化合物,其中有12个是(S)-(+)-α-甲基丁酰基间苯三酚类化合物。通过对新化合物旋光资料的研究和分析,找到了它们绝对构型与旋光方向的关系。该规律在测定光学活性的α-甲基丁酰基间苯三酚类化合物的绝对构型和开发研究该类药物上,均具有一定的实际应用价值。     

Total radical trapping antioxidant potential (TRAP) and exercise

The relationship between physical activity, physical fitness and total radical trapping antioxidant potential (TRAP) was examined in the Northern Ireland Health and Activity Survey. This was a cross-sectional population study (n = 1600) using a two-stage probability sample of the population. TRAP was calculated using the sum of the individual serum antioxidant concentrations (urate, protein thiols, ascorbate, alpha tocopherol and bilirubin) multiplied by their respective stoichiometric values. Physical fitness was determined by estimation of VO2max by extrapolation from submaximal oxygen uptake, and physical activity was recorded by computer-assisted interview. Mean serum TRAP concentrations were significantly higher in males (653 +/- 8.2 mumol/l, mean +/- SEM) compared to females (564 +/- 8.0 mumol/l) (p < 0.0001). Both male and female smokers had significantly lower TRAP values than non-smokers (males p < 0.0001, females p = 0.02). In females, there was a positive relationship of TRAP with age (p < 0.001) and body mass index (p < 0.001) but a negative relationship with physical fitness (p < 0.05). The known beneficial effects of exercise and activity do not appear to be directly mediated through increased antioxidant status.      

Voxel-based morphometry reveals increased gray matter density in Broca's area in male symphony orchestra musicians

Broca's area is a major neuroanatomical substrate for spoken language and various musically relevant abilities, including visuospatial and audiospatial localization. Sight reading is a musician-specific visuospatial analysis task, and spatial ability is known to be amenable to training effects. Musicians have been reported to perform significantly better than nonmusicians on spatial ability tests, which is supported by our findings with the Benton judgement of line orientation (JOL) test (P < 0.001). We hypothesised that use-dependent adaptation would lead to increased gray matter density in Broca's area in musicians. Voxel-based morphometry (VBM) and stereological analyses were applied to high-resolution 3D MR images in male orchestral musicians (n = 26) and sex, handedness, and IQ-matched nonmusicians (n = 26). The wide age range (26 to 66 years) of volunteers permitted a secondary analysis of age-related effects. VBM with small volume correction (SVC) revealed a significant (P = 0.002) region of increased gray matter in Broca's area in the left inferior frontal gyrus in musicians. We observed significant age-related volume reductions in cerebral hemispheres, dorsolateral prefrontal cortex subfields bilaterally and gray matter density in the left inferior frontal gyrus in controls but not musicians; a positive correlation between JOL test score and age in musicians but not controls; a positive correlation between years of playing and the volume of gray matter in a significant region identified by VBM in under-50-year-old musicians. We suggest that orchestral musical performance promotes use-dependent retention, and possibly expansion, of gray matter involving Broca's area and that this provides further support for shared neural substrates underpinning expressive output in music and language.     

Decreasing expander breast infection: A new drain care protocol

BACKGROUND:

Risk factors for expander reconstruction infection are well known. However, drain use as a risk factor for the development of infection is unclear.

OBJECTIVE:

To review a simple method for drain use to help reduce rates of infection in expander breast reconstruction.

METHODS:

Two hundred consecutive single-surgeon (JDM) immediate first-stage expander breast reconstructions were retrospectively reviewed. The records were reviewed for history and physical examination, intra-operative technique, perioperative management, adjuvant therapy, and outcome with respect to expander infection necessitating premature explantation within the first eight weeks. Infection was defined on clinical basis, with or without culture positivity. All expanders (Mentor, USA) were the same model (textured, port-integrated and biodimensional). Two consecutive series of reconstructions were then created. The first series included 177 reconstructions while the second series included 23 reconstructions. Unlike the first series, the second series introduced a protocol in which all reconstructions received mupirocin 2% cream to the drain sites and all drains were removed at the end of the first week. Additionally, in the second series, all expanders were secluded from direct in vivo contact with the closed suction drain either by the use of an intervening Alloderm sling (LifeCell Corporation, USA, 15 of 23 breasts) or by subdermally tunnelling the drain superficial to an adequate fatty subcutaneous layer (eight of 23 breasts).

RESULTS:

Patients who developed infection in the first series and all patients in the second series shared statistically the same level of aggregate risk factors (P=0.531). The infection rate (5.65%, 10 infections in 177 breasts) in the first series was statistically greater than in the second series (0%, 0 in 23 breasts, P=0.001).

CONCLUSIONS:

The present study found that percutaneous closed suction drains do serve as an increased risk for expander infection. However, early results indicate that in vivo protection of the expander with Alloderm or subdermal tunnelling, topical antibiotic ointment use and early drain removal may significantly reduce expander infection.     

Assisting cognitively impaired nursing home residents with bathing: effects of two bathing interventions on caregiving

PURPOSE: When cognitively impaired nursing home residents exhibit agitated and aggressive behaviors during bathing, nursing home caregivers are in a unique position to improve residents' experience. This report addresses whether certified nursing assistants (CNAs) who received training in a person-centered approach with showering and with the towel bath showed improved caregiving behaviors (gentleness and verbal support) and experienced greater preparedness (confidence and ease) and less distress (hassles) when assisting residents with bathing. DESIGN AND METHODS: We used a crossover design and randomized 15 nursing homes into two treatment groups and a control group of 5 facilities each. In one treatment group, CNAs received person-centered training, first with showering for 6 weeks (Time 1) and then with the towel bath for 6 weeks (Time 2). We reversed the treatment order in the other treatment group. Control group CNAs used usual showering procedures without person-centered training. We collected observational and self-report data at baseline and at the end of Time 1 and Time 2 on five caregiving outcomes. We analyzed data from 37 CNAs assisting 69 residents by using 3x2 repeated measures analyses of variance to compare the three groups on change from baseline. RESULTS: Compared with the control group, treatment groups significantly improved in the use of gentleness and verbal support and in the perception of ease. IMPLICATIONS: A person-centered approach with showering and with the towel bath improved not only how care is given to residents who become agitated and aggressive during bathing but also how CNAs perceive their experience when bathing these residents.     

Urea unfolding of peptide helices as a model for interpreting protein unfolding.

To provide a model system for understanding how the unfolding of protein alpha-helices by urea contributes to protein denaturation, urea unfolding was measured for a homologous series of helical peptides with the repeating sequence Ala-Glu-Ala-Ala-Lys-Ala and chain lengths varying from 14 to 50 residues. The dependence of the helix propagation parameter of the Zimm-Bragg model for helix-coil transition theory (s) on urea molarity ([urea]) was determined at 0 degree C with data for the entire set of peptides, and a linear dependence of In s on [urea] was found. The results were fitted by the binding-site model and by the solvent-exchange model for the interaction of urea with the peptides. Each of these thermodynamic models is able to describe the data quite well and we are not able to discern any difference between the ability of each model to fit the data. Thus a linear relation, ln s = ln s0 - (m/RT).[urea], fits the data for alpha-helix unfolding, just as others have found for protein unfolding. When the m value determined here for alpha-helix unfolding is multiplied by the number of helical residues in partly helical protein molecules, the resulting values agree within a factor of 2 with observed m values for these proteins. This result indicates that the interaction between urea and peptide groups accounts for a major part of the denaturing action of urea on proteins, as predicted earlier by some model studies with small molecules.