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1.
Various N--hydroxyalkyl derivatives of N-acyl amino acids and di- and tripeptides were prepared by hydrolysis or aminolysis of N-acyl 5-oxazolidinones. The stability of these derivatives was studied in aqueous solution as a function of pH. The compounds were all degraded quantitatively to their parent N-acylated amino acid or peptide and aldehyde but with vastly different rates. At pH 7.4 and 37°C the half-lives of decomposition ranged from 4 min to 1500 hr. The structural factors influencing the stability included both steric and polar effects within the acyl and N--hydroxyalkyl moieties as well as within the amino acid attached to the N--hydroxyalkylated N-acyl amino acid. Whereas the N-benzyloxycarbonyl (Z) derivatives of the dipeptides Gly-L-Leu and Gly-L-Ala were readily hydrolyzed by carboxypeptidase A, the N-hydroxymethylated compounds, i.e., Z-Gly(CH2OH)-Leu and Z-Gly(CH2OH)-Ala, were resistant to cleavage by the enzyme as revealed by their similar rates of decomposition in the presence or absence of the enzyme at pH 7.4 and 37°C. The results suggest that N--hydroxyalkylation of a peptide bond protects not only this bond but also an adjacent peptide bond against proteolytic cleavage. Since the N--hydroxyalkyl derivatives are readily bioreversible, undergoing spontaneous hydrolysis at physiological pH, this prodrug approach promises to overcome the enzymatic barrier to absorption of various peptides.  相似文献   
2.
2-Acetyl-2-decarboxamido-oxytetracycline (ADOTC) is a major impurity of oxytetracycline (OTC) produced as a side product during fermentation. ADOTC was isolated from OTC and other impurities using preparative HPLC. The preparative column was an Xterra MS, C18 chromatographic column (100 mm x 19 mm i.d., 5 microm), and the mobile phase contained methanol-water (27:73 (v/v)) with 0.08 M formic acid added. The flow rate was 9.0 ml/min. It was possible to isolate few milligram ADOTC in a day. The compound was unambiguously identified using NMR and MS-MS. The anti-microbial activity against activated sludge bacteria was determined giving a potency of only 3% of that of OTC. With tetracycline-resistant bacteria, no anti-microbial activity was observed, indicating a mode of action similar to that of OTC.  相似文献   
3.
ObjectiveGeneral practice plays an important role in cancer trajectories, and cancer patients request the continuous involvement of general practice. The objective of this scoping review was to identify healthcare practices that increase the quality of care in cancer trajectories from a general practice perspective.Design, setting, and subjectsA scoping review of the literature published in Danish or English from 2010 to 2020 was conducted. Data was collected using identified keywords and indexed terms in several databases (PubMed, MEDLINE, EBSCO CINAHL, Scopus, and ProQuest), contacting key experts, searching through reference lists, and reports from selected health political, research- and interest organizations’ websites.Main outcome measuresWe identified healthcare practices in cancer trajectories that increase quality care. Identified healthcare practices were grouped into four contextual domains and allocated to defined phases in the cancer trajectory. The results are presented according to the Preferred Reporting Items for Systematic Reviews and Meta-analysis extension for scoping reviews (PRISMA-ScR).ResultsA total of 45 peer-reviewed and six non-peer-reviewed articles and reports were included. Quality of care increases in all phases of the cancer trajectory when GPs listen carefully to the full story and use action plans. After diagnosis, quality of care increases when GPs and practice staff have a proactive care approach, act as interpreters of diagnosis, treatment options, and its consequences, and engage in care coordination with specialists in secondary care involving the patient.ConclusionThis scoping review identified healthcare practices that increase the quality of care in cancer trajectories from a general practice perspective. The results support general practice in investigating own healthcare practices and identifying possibilities for quality improvement.

KEY POINTS

  • Identified healthcare practices in general practice that increase the quality of care in cancer trajectories:
  • Listen carefully to the full story
  • Use action plans and time-out-consultations
  • Plan and provide proactive care
  • Act as an interpreter of diagnosis, treatment options, and its consequences for the patient
  • Coordinate care with specialists, patients, and caregivers with mutual respect
  • Identified barriers for quality of care in cancer trajectories are:
  • Time constraints in consultations
  • Limited accessibility for patients and caregivers
  • Health practices to increase the quality of care should be effective, safe, people-centered, timely, equitable, integrated, and efficient. These distinctions of quality of care, support general practice in investigating and improving quality of care in cancer trajectories.
  相似文献   
4.
Communication between the amygdala and other brain regions critically regulates sensitivity to threat, which has been associated with risk for mood and affective disorders. The extent to which these neural pathways are genetically determined or correlate with risk-related personality measures is not fully understood. Using functional magnetic resonance imaging, we evaluated independent and interactive effects of the 5-HTTLPR genotype and neuroticism on amygdala functional connectivity during an emotional faces paradigm in 76 healthy individuals. Functional connectivity between left amygdala and medial prefrontal cortex (mPFC) and between both amygdalae and a cluster including posterior cingulate cortex, precuneus and visual cortex was significantly increased in 5-HTTLPR S′ allele carriers relative to LALA individuals. Neuroticism was negatively correlated with functional connectivity between right amygdala and mPFC and visual cortex, and between both amygdalae and left lateral orbitofrontal (lOFC) and ventrolateral prefrontal cortex (vlPFC). Notably, 5-HTTLPR moderated the association between neuroticism and functional connectivity between both amygdalae and left lOFC/vlPFC, such that S′ carriers exhibited a more negative association relative to LALA individuals. These findings provide novel evidence for both independent and interactive effects of 5-HTTLPR genotype and neuroticism on amygdala communication, which may mediate effects on risk for mood and affective disorders.  相似文献   
5.
Background: The mechanisms underlying neuropathic pain are incompletely understood. Targeting specific molecular mechanisms in the pain signaling system may assist in understanding key features in neuropathic pains such as allodynia. This study examined the effect of systemically administered ketamine, an N-methyl-d-aspartate receptor antagonist and lidocaine, a sodium channel blocker, on spontaneous pain, brush-evoked pain, and pinprick-evoked pain in patients with nerve injury pain.

Methods: Twenty patients participated in two randomized, double-blinded, placebo-controlled, crossover experiments in which they, on four different days, received a 30-minute intravenous infusion of ketamine (0.24 mg/kg), lidocaine (5 mg/kg), or saline. Ongoing pain, pain evoked by brush and repetitive pinprick stimuli, and acetone was measured before, during, and after infusion.

Results: Ketamine significantly reduced ongoing pain and evoked pain to brush and pinprick, whereas lidocaine only reduced evoked pain to repetitive pinprick stimuli. In individual patients, there was no correlation between the pain-relieving effect of lidocaine and ketamine on ongoing or mechanically evoked pains.  相似文献   

6.
Giant cell tumor of bone (GCTB) is a benign bone tumor with a shown clinical behavior of local recurrences and rare distant metastases. GCTB is composed of uniformly distributed osteoclastic giant cells, thought to originate from the fusion of monocyte–macrophage lineage cells, in a background consisting of mononuclear rounded cells and spindle‐shaped cells. Several reports showed the specific expression of markers, such as CD14 on the mononuclear rounded cell population, however, lacking osteoclastic giant cells. Blood monocytes that were CD14+, CD33+, or CD14+/CD33+ have also been shown to be programmed as pre‐osteoclasts. The macrophage marker CD33 is expressed earlier than CD14 in macrophage maturation, whereas CD14 is expressed longer than CD33. The aim of this study was to investigate CD14/CD33 expression profiles in GCTB. Nineteen GCTB tumor samples of 19 patients were studied. Immunofluorescent analyses were performed with monoclonal antibodies against CD14, CD33, RANK, and CD51. To unambiguously further prove the expression of these molecules, quantitative RT‐PCR was used with subsequent sequencing of its products. All samples showed similar immunoreactivity profiles. The mononuclear rounded cell population was positive for RANK, CD51, CD14, and CD33. The osteoclastic giant cell population expressed RANK and CD51, as well as CD33, but was consistently negative for CD14 expression. The CD14 and CD33 profiles were confirmed by quantitative RT‐PCR. These RT‐PCR products were sequence verified. Osteoclasts in GCTB are the result of fusion of CD33‐expressing pre‐osteoclasts that further fuse with CD14+ mononuclear cells. Although these results reflect a static rather than a dynamic spectrum, we strongly believe that osteoclastogenesis seems not to be the exclusive result of fusion of intratumoral CD14+ mononuclear cells. Moreover, CD33‐modulated osteoclastogenesis opens up the possibility for novel therapeutic directions.  相似文献   
7.
Ortoft G  Andreassen TT  Oxlund H 《BONE》2005,36(1):123-133
We evaluated the effect of glucocorticoids (GC) and growth hormone (GH) on cortical and cancellous bone turnover in adult rats using random vertical sections giving valid measurements of bone surfaces and bone formation parameters. GH administration could reverse GC-induced osteopenia and low bone turnover of cortical bone. However, GH could not reverse the GC-induced low bone turnover of cancellous bone. METHODS: Seventy female Wistar rats, 7 months of age, were divided into five groups: (1) start control, (2) saline, (3) GC 9 mg/kg/day (Solu Medrol), (4) GH 5 mg/kg/day, and (5) GC 9 mg/kg/day + GH 5 mg/kg/day, and injected for 3 months. The vertebral body was examined using dynamic histomorphometry and biomechanical tests. Nonparametric methods were used. RESULTS: Glucocorticoid administration induced a low bone turnover state of both the cortical and cancellous bone of the vertebral body, without altering the absolute amount of bone or the biomechanical competence of the vertebral body. GH administration induced a small increase in longitudinal bone growth and ventral modeling drift. This growth increased the total amount of cortical, endocortical, and cancellous bone in the vertebra. The biomechanical competence of a 3.5-mm-high cylinder of the central vertebral body was also increased due to an increase in the amount of cortical bone, whereas the total amount of cancellous bone in the cylinder was unaltered. The cancellous bone density (CBV) was, however, increased due to thicker trabeculae probably induced by an accelerated mineral appositional rate (MAR) induced by GH. GH also increased longitudinal and ventral modeling drifts in the GC-injected animals. GH increased the amount of cortical bone and also the amount of cancellous bone close to the epiphyseal growth plate, whereas the cancellous bone volume of the central vertebral cylinder was unaffected by GH administration in GC-injected animals. GH could also increase parameters of bone formation (bone mineralizing surface (MS) and MAR) on cortical bone surfaces in GC-injected animals, whereas parameters of bone formation [MS and bone formation rates (BFR)] on cancellous bone surfaces were even lower than those of animals injected with GC alone. CONCLUSION: GH can reverse GC-induced low bone turnover on cortical but not on cancellous bone surfaces.  相似文献   
8.
Background: Neuropathic pain in spinal cord injury is a common challenging therapeutic condition. The current study examines the analgesic effect of the sodium channel blocker lidocaine on neuropathic pain in patients with spinal cord injury and the predictive role of concomitant evoked pain on pain relief with lidocaine.

Methods: Twenty-four spinal cord injury patients with neuropathic pain at or below the level of injury were randomized and completed a double-blind crossover trial of 5 mg/kg lidocaine and placebo infused over 30 min. Twelve patients reported evoked pain, and 12 patients had no evoked pain. Spontaneous and evoked pains were assessed using a visual analog scale and quantitative sensory testing.

Results: Lidocaine significantly reduced spontaneous pain in all patients (P < 0.01) and in each of the two groups with (P < 0.01) and without (P = 0.048) evoked pain, with no difference in number of responders (pain reduction >= 33%) between the patients with (n = 6) and without (n = 5) evoked pain. Lidocaine significantly relieved both at-level and below-level neuropathic pain and decreased brush-evoked dysesthesia but not cold allodynia, pinprick hyperalgesia, or pain evoked by repetitive pinprick.  相似文献   

9.
BackgroundAllergic rhinitis (AR), allergic conjunctivitis (AC), and asthma composing multiple phenotypes and improved understanding of these phenotypes and their respective risk factors are needed.ObjectivesThe objective of this study was to define the prevalence of AR, AC, and asthma and their association with allergen‐specific immunoglobulin E (sIgE) sensitization in a large cohort of blood donors and identify risk factors.MethodsFrom the nationwide population‐based Danish Blood Donor Study, 52,976 participants completed an electronic questionnaire including AR, AC, asthma, allergic predisposition, and childhood residence. Of these, 25,257 were additionally tested for sIgE to inhalation allergens (Phadiatop).ResultsThe prevalence of sIgE sensitization, AR, AC, and asthma was 30%, 19%, 15%, and 9%, respectively. The youngest birth cohorts had the highest prevalence of sIgE sensitization and symptoms of asthma, AR, and AC, and for asthma, they apparently experienced symptoms at an earlier age. The sIgE sensitization was positively associated with male sex. The sIgE seroprevalence was higher in participants with both AR and AC (ARC) than in participants with either AR or AC. Allergic predisposition and sIgE sensitization increased the risk of the diseases, while farm upbringing was associated with reduced prevalence of ARC, however, only in sIgE sensitized participants.ConclusionBirth year, childhood residence, sIgE sensitization, and allergic predisposition were associated with asthma, AR, and AC prevalence. Individuals with self‐reported ARC represent a primarily sIgE‐positive phenotype, while those with either AR or AC represent more diverse phenotypes.  相似文献   
10.

Introduction

As the human immunodeficiency virus (HIV)-positive population ages, issues concerning sexuality and fertility, among others, are becoming relevant. HIV is still surrounded by stigma and taboos, and there have been few studies conducted in industrialized settings concerning these questions. We therefore wanted to investigate the perception of sexuality and fertility in women living with HIV (WLWH) in an industrialized setting, using a questionnaire.

Methods

WLWH were recruited at their regular outpatient clinic visits, at the major Departments of Infectious Diseases in Denmark and Finland, from January 2012 to October 2013. A questionnaire was developed, study participants were informed of the nature of study and, if they agreed to participate and signed a consent form, they filled in the questionnaire. Demographic information on the participants was obtained from patient files (in Finland) or from a national HIV cohort (in Denmark). Statistical analysis was performed using STATA®, version 11.

Results

In total, 560 women were included in the study. The median age was 44 years. The majority were of white European origin, with fully suppressed HIV viral load, CD4 cell count >350 µL and mild or no symptoms of their HIV infection. A total of 62% were sexually active, stating condom use as their sole form of contraception. Of the sexually inactive women, one-third were in steady relationships. Eighty percent reported prior pregnancies, of which the majority had one or more children. Most children were born prior to the women''s HIV diagnosis and the mode of conception was predominantly natural. One-quarter of the participating women desired pregnancy, while more than half did not. The remaining quarter either stated that they already had the desired number of children or chose not to answer the question. Fourteen percent stated that their HIV diagnosis ended their wish for children; of these women, the median time of diagnosis was between 1995 and 1996. Pregnancy had been attempted unsuccessfully in one-quarter of study participants. The final question inquired what the risk of mother-to-child transmission was, with all precautions taken. Fifteen percent estimated the risk to be above two percent.

Conclusions

In conclusion, the majority of WLWH in industrialized settings in Denmark and Finland have few HIV-related symptoms, are sexually active and have a strong desire for children.  相似文献   
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