白芍总苷治疗干燥综合征的研究进展

干燥综合征（SS）是一种慢性自身免疫性疾病,常侵犯泪腺、唾液腺等外分泌腺,同时还会造成肺、肾、消化和神经系统损害甚至累及全身器官。其病因复杂,发病机制目前尚未完全阐明。本病临床治疗为对症治疗,常用药物为免疫抑制剂,糖皮质激素等。白芍总苷辅助治疗本病可改善患者的外分泌腺功能,具有较好的临床疗效和安全性。本文从白芍总苷治疗SS的相关机制进行综述,以期为相关实验研究及临床提供更多的理论依据。     

Comparison of two screen-film combinations in contact and magnification mammography: detectability of microcalcifications

A new dual-screen, dual-emulsion-film combination that allows a decrease in radiation dose of approximately 66% was compared with a widely used single-screen, single-emulsion-film system in contact and magnification mammography. Clustered microcalcifications randomly superimposed on a breast phantom were detected, and the location and number of individual calcifications were determined by four observers. The detectability of calcifications, determined with a receiver operating characteristic (ROC) analysis area, was 0.92 for magnification and 0.82 for contact mammography with the single-emulsion-film system, compared with 0.84 and 0.72, respectively, with the dual-emulsion-film system. More clusters were correctly located and more individual calcifications were counted with magnification than with contact mammography. The dual-emulsion-film system with the magnification technique performs as well as the single-emulsion-film system with the contact technique, while retaining a decrease in required dose of approximately 40%.     

Development of a stratum corneum and barrier function in an organotypic skin culture

The stratum corneum of human skin is responsible for maintaining the epidermal permeability barrier. We have developed a bilayered skin culture (SC) which forms a corneum 35 ± 1 cell layers thick 21 days after being raised to the air-liquid (A/L) interface. By the 7th day after raising to the A/L interface the corneocytes were irregularly shaped and had cross-sectional areas (CSA) of 300 m². By the 21st day the corneocytes had assumed polygonal shapes and had a CSA (100–250 m²) similar to that of human foreskin. The total lipid (TL) content of the corneum averaged 5–7% of the lyophilized weight. Ceramide content increased from 20% of TL at day 7 of A/L interface culture to 30% at day 21. Triglycerides decreased from 43% to 17% of TL during the same period. Free fatty acids comprised 5.5% of TL at day 21 of A/L interface culture. The intercorneocyte spaces contained stacks of lipid lamellae. However, the stacks lacked the Landmann unit repeat. Abnormal lamellar structures were observed in both the intra- and extracorneocyte spaces. Transepidermal water loss (TEWL) was >4 mg/cm² per h throughout the culture period. Lipid supplementation of the culture medium and culturing in a low humidity environment improved barrier function by 50%. However, the effects were not additive. The SC developed a near-normal corneum, but did not achieve barrier competence, due at least partially to abnormalities in lipid composition and organization. Improvement of barrier function with lipid supplementation or low humidity indicates that modifications of the culture environment may facilitate the SC in assembling a permeability barrier equivalent to human skin.     

Production of chitosan from endolichenic fungi isolated from mangrove environment and its antagonistic activity

Objective

To screen the chitosan producing ability of endolichenic fungi and its antibacterial activity.

Methods

Lichen collected from mangroves was screened for endophytes and the chitosan producing ability of endolichenic fungi by submerged fermentation was also determined. Antibacterial activity was carried out against different pathogens.

Results

Totally 4 different groups of fungi were isolated from the lichen Roccella montagnei. Among the four genera, Aspergillus niger (A. niger) is potential to produce chitosan (1.3 g/L) on the twelfth day of incubation. Glucose plays an important role in the productivity of chitosan and the yield was maximum at 10% (1.93 g/L). Antibacterial activity revealed that Vibrio cholerae was sensitive to chitosan followed by Escherichia coli.

Conclusions

In conclusion, our findings suggest that A. niger is a potential candidate to produce more chitosan than the other strains and glucose plays an important role in the production of chitosan which proves to have a good antibacterial activity.     

Quantifying the risks and benefits of efavirenz use in HIV‐infected women of childbearing age in the USA

Objectives

The aim of the study was to quantify the benefits (life expectancy gains) and risks (efavirenz‐related teratogenicity) associated with using efavirenz in HIV‐infected women of childbearing age in the USA.

Methods

We used data from the Women's Interagency HIV Study in an HIV disease simulation model to estimate life expectancy in women who receive an efavirenz‐based initial antiretroviral regimen compared with those who delay efavirenz use and receive a boosted protease inhibitor‐based initial regimen. To estimate excess risk of teratogenic events with and without efavirenz exposure per 100 000 women, we incorporated literature‐based rates of pregnancy, live births, and teratogenic events into a decision analytic model. We assumed a teratogenicity risk of 2.90 events/100 live births in women exposed to efavirenz during pregnancy and 2.68/100 live births in unexposed women.

Results

Survival for HIV‐infected women who received an efavirenz‐based initial antiretroviral therapy (ART) regimen was 0.89 years greater than for women receiving non‐efavirenz‐based initial therapy (28.91 vs. 28.02 years). The rate of teratogenic events was 77.26/100 000 exposed women, compared with 72.46/100 000 unexposed women. Survival estimates were sensitive to variations in treatment efficacy and AIDS‐related mortality. Estimates of excess teratogenic events were most sensitive to pregnancy rates and number of teratogenic events/100 live births in efavirenz‐exposed women.

Conclusions

Use of non‐efavirenz‐based initial ART in HIV‐infected women of childbearing age may reduce life expectancy gains from antiretroviral treatment, but may also prevent teratogenic events. Decision‐making regarding efavirenz use presents a trade‐off between these two risks; this study can inform discussions between patients and health care providers.     

Emergency department utilization among HIV‐infected patients in a multisite multistate study*

Objective

The aim of this study was to examine Emergency Department (ED) utilization and clinical and sociodemographic correlates of ED use among HIV‐infected patients.

Methods

During 2003, 951 patients participated in face‐to‐face interviews at 14 HIV clinics in the HIV Research Network. Respondents reported the number of ED visits in the preceding 6 months. Using logistic regression, we identified factors associated with visiting the ED in the last 6 months and admission to the hospital from the ED.

Results

Thirty‐two per cent of respondents reported at least one ED visit in the last 6 months. In multivariate analysis, any ED use was associated with Medicaid insurance, high levels of pain (the third or fourth quartile), more than seven primary care visits in the last 6 months, current or former illicit drug use, social alcohol use and female gender. Of those who used ED services, 39% reported at least one admission to the hospital. Patients with pain in the highest quartile reported increased admission rates from the ED as did those who made six or seven primary care visits, or more than seven primary care visits vs. three or fewer.

Conclusions

The likelihood of visiting the ED has not diminished since the advent of highly active antiretroviral therapy (HAART). More ED visits are to treat illnesses not related to HIV or injuries than to treat direct sequelae of HIV infection. With the growing prevalence of people living with HIV infection, the numbers of HIV‐infected patients visiting the ED may increase, and ED providers need to understand potential complications produced by HIV disease.     

Steady‐state amprenavir and tenofovir pharmacokinetics after coadministration of unboosted or ritonavir‐boosted fosamprenavir with tenofovir disoproxil fumarate in healthy volunteers

Objective

An open‐label, three‐period pharmacokinetic study was conducted to investigate the drug interaction potential between fosamprenavir (FPV) and tenofovir disoproxil fumarate (TDF).

Methods

Thirty‐six healthy subjects received TDF 300 mg once daily (qd) for 7 days (period 1), and then were randomized to 14 days of either FPV 1400 mg twice daily (bid) or FPV/ritonavir (RTV) 700/100 mg bid alone or with TDF (period 2). Subjects continued their randomized dose of FPV for 14 more days, adding or removing TDF based upon its receipt in period 2 (period 3). Twenty‐four‐hour pharmacokinetic sampling was carried out on day 7 of period 1 and on day 14 of periods 2 and 3. Steady‐state plasma amprenavir (APV) and tenofovir (TFV) pharmacokinetics were assessed by noncompartmental analysis and parameter values observed with each regimen were compared using geometric mean ratios with 90% confidence intervals.

Results

After TDF coadministration, APV geometric mean minimum concentration (C_min), maximum concentration (C_max), and area under the plasma concentration–time curve (AUC) increased by 31, 3 and 7% above values observed with unboosted FPV alone; they also increased by 31, 4 and 16% above values observed with FPV/RTV alone. TFV C_min, C_max and AUC decreased by 12, 25 and 15% after FPV coadministration and by 9, 18 and 7% after FPV/RTV coadministration. No significant changes in RTV pharmacokinetics were observed. No differences were noted in adverse events among dosing periods.

Conclusions

In this evaluation of the interaction between FPV and TDF, increases in APV exposures and modest decreases in TFV exposures were observed. These were unlikely to be clinically significant.