Development of a risk-predicting score for hip preservation with bone grafting therapy for osteonecrosis

Identification and differentiation of appropriate indications on hip preserving with bone grafting therapy remains a crucial challenge in the treatment of osteonecrosis of the femoral head (ONFH). A prospective cohort study on bone grafting therapy for ONFH aimed to evaluate hip survival rates, and to establish a risk scoring derived from potential risk factors (multivariable model) for hip preservation. Eight variables were identified to be strongly correlated with a decreased rate of hip survival post-therapy, and a comprehensive risk scoring was developed for predicting hip-preservation outcomes. The C-index stood at 0.72, and the areas under the receiver operating characteristics for the risk score's 5- and 10-year hip failure event predictions were 0.74 and 0.72, respectively. This risk score outperforms conventional methods in forecasting hip preservation. Bone grafting shows sustained benefits in treating ONFH when applied under the right indications. Furthermore, the risk scoring proves valuable as a decision-making tool, facilitating risk stratification for ONFH treatments in future.

In-hospital waiting time to surgery and functional outcomes in geriatric hip fractures: a directed acyclic graph-based preplanned analysis from a prospective multicenter cohort study

BACKGROUND

The early recovery of hip function after hip fracture surgery values more attention, especially for patients with delayed surgery of longer than 48 h. We aim to evaluate the associations of in-hospital surgical waiting time with the functional outcomes [Harris Hip Score (HHS), Parker Mobility Score (PMS), and EuroQol 5 dimensions VAS (visual analogue scale) score (EQ-5D VAS)] in elderly patients who sustained hip fractures.

MATERIALS AND METHODS

Data on sociodemographic and clinical factors were prospectively collected using a multicenter hip fracture registry system. Participants in the cohort underwent a 12-month follow-up investigation. After adjusting potential confounders identified by the directed acyclic graphs, the associations between surgical waiting time longer than 48 h and functional outcomes were estimated by log-binomial regression and multivariable linear regression models with generalized estimating equations.

RESULTS

Of 863 survival participants with available functional data at 12 months after surgery, an increased risk was obtained from receiving surgery after 48 h and the poor functional outcomes (HHS<80: relative risk (RR)=1.56, 95% CI: 1.00-2.51; PMS<7: RR=1.49, 95% CI: 1.13-2.01; EQ-5D VAS<80: RR=1.97, 95% CI: 1.57-2.47). In-hospital waiting time greater than 48 h were time-invariantly associated with lower PMS during recovery (-0.44 units 95% CI: -0.70 to -0.18). In addition, delayed surgery was time-varying associated with HHS and EQ-5D VAS.

CONCLUSIONS

The associations between in-hospital waiting time and postoperative functional score suggest that delayed surgery can lead to poor functional outcomes, especially in patients waiting longer than 72 h from injury. Delayed surgery mainly impacted hip function and mobility recovery with a slower speed in early recovery of the first 3 months. More attention should be paid to mechanisms behind the associations between delayed surgery on general healthy status.

[Analysis of incidence and clinical characteristics of osteonecrosis of femoral head in patients with systemic lupus erythematosus treated with glucocorticoid: A descriptive study based on a prospective cohort]

Objective

To describe the disease characteristics of osteonecrosis of the femoral head (ONFH) in patients with systemic lupus erythematosus (SLE) who experiencing prolonged glucocorticoid (GC) exposure.

Methods

Between January 2016 and June 2019, 449 SLE patients meeting the criteria were recruited from multiple centers. Hip MRI examinations were performed during screening and regular follow-up to determine the occurrence of ONFH. The cohort was divided into ONFH and non-ONFH groups, and the differences in demographic baseline characteristics, general clinical characteristics, GC medication information, combined medication, and hip clinical features were compared and comprehensively described.

Results

The age at SLE diagnosis was 29.8 (23.2, 40.9) years, with 93.1% (418 cases) being female. The duration of GC exposure was 5.3 (2.0, 10.5) years, and the cumulative incidence of SLE-ONFH was 9.1%. Significant differences ( P<0.05) between ONFH and non-ONFH groups were observed in the following clinical characteristics: ① Demographic baseline characteristics: ONFH group had a higher proportion of patients with body mass index (BMI)<20 kg/m ² compared to non-ONFH group. ② General clinical characteristics: ONFH group showed a higher proportion of patients with cutaneous and renal manifestations, positive antiphospholipid antibodies (aPLs) and anticardiolipin antibodies, severe SLE patients [baseline SLE Disease Activity Index 2000 (SLEDAI-2K) score ≥15], and secondary hypertension. Fasting blood glucose in ONFH group was also higher. ③ GC medication information: ONFH group had higher initial intravenous GC exposure rates, duration, cumulative doses, higher cumulative GC doses in the first month and the first 3 months, higher average daily doses in the first 3 months, and higher proportions of average daily doses ≥15.0 mg/d and ≥30.0 mg/d, as well as higher full-course average daily doses and proportion of full-course daily doses ≥30.0 mg/d compared to non-ONFH group. ④ Combined medications: ONFH group had a significantly higher rate of antiplatelet drug use than non-ONFH group. ⑤ Hip clinical features: ONFH group had a higher proportion of hip discomfort or pain and a higher incidence of hip joint effusion before MRI screening than non-ONFH group.

Conclusion

The incidence of ONFH after GC exposure in China's SLE population remains high (9.1%), with short-term (first 3 months), medium-to-high dose (average daily dose ≥15 mg/d) GC being closely associated with ONFH. Severe SLE, low BMI, certain clinical phenotypes, positive aPLs, and secondary hypertension may also be related to ONFH.

Development of a Conjugation-Based Genome Editing System in an Undomesticated Bacillus subtilis Strain for Poly-γ-glutamic Acid Production with Diverse Molecular Masses

Poly-γ-glutamic acid (γ-PGA) is a biodegradable polymer produced by microorganisms. Biosynthesizing γ-PGA with diverse molecular masses (M_w) is an urgent industrial technical problem to be solved. Bacillus subtilis KH2, a high-M_w γ-PGA producer, is an ideal candidate for de novo production of γ-PGA with diverse M_w values. However, the inability to transfer DNA to this strain has limited its industrial use. In this study, a conjugation-based genetic operating system was developed in strain KH2. This system enabled us to modify the promoter of γ-PGA hydrolase PgdS in strain KH2 chromosome to de novo biosynthesize γ-PGA with diverse M_ws. The conjugation efficiency was improved to 1.23 × 10^-4 by establishing a plasmid replicon sharing strategy. A further increase to 3.15 × 10^-3 was achieved after knocking out two restriction endonucleases. To demonstrate the potential of our newly established system, the pgdS promoter was replaced by different phase-dependent promoters. A series of strains producing γ-PGA with specific M_ws of 411.73, 1356.80, 2233.30, and 2411.87 kDa, respectively, were obtained. The maximum yield of γ-PGA was 23.28 g/L. Therefore, we have successfully constructed ideal candidate strains for efficient γ-PGA production with a specific M_w value, which provides an important research basis for sustainable production of desirable γ-PGA.

[Association between blood pressure during 12-28 weeks gestation and pre-eclampsia: predictive value of blood pressure trajectories constructed by latent class growth modeling]

Objective: To explore the associations between blood pressure trajectories during pregnancy and risk of future pre-eclampsia in a large cohort enrolling pregnant women at gestational age of ~12 weeks from community hospitals in Tianjin. Latent class growth modeling (LCGM) was used to model the blood pressure trajectories. Methods: This was a large prospective cohort study. The study enrolled pregnant women of ~12 weeks of gestation in 19 community hospitals in Tianjin from November 1, 2016 to May 30, 2018. We obtained related information during 5 antepartum examinations before gestational week 28, i.e., week 12, week 16, week 20, week 24 and week 28. LCGM was used to model longitudinal systolic (SBP) and diastolic blood pressure (DBP) trajectories. For the association study, the predictors were set as SBP and DBP trajectory membership (built separately), the outcome was defined as the occurrence of preeclampsia after 28 weeks of gestation. Results: A total of 5 809 cases with known pregnant outcomes were documented. After excluding 249 cases per exclusion criteria, 5 560 cases with singleton pregnancy were included for final analysis. There were 128 cases preeclampsia and 106 cases gestational hypertension in this cohort. Univariate logistic regression and multivariate logistic regression showed the higher baseline SBP level and DBP level were related with increased risk of preeclampsia. Four distinctive SBP trajectories and DBP trajectories from 12 weeks to 28 weeks of gestation were identified by LCGM. After controlling for potential confounders (baseline BMI, being primipara or not, white blood cell counts, hemoglobin level, platelet counts and alanine aminotransferase level), the OR for SBP latent classification trajectory_ 4 was 4.023 (95%CI: 2.368 to 6.835, P<0.001), and the OR for SBP latent classification trajectory_3 was 1.854 (95%CI: 1.223 to 2.811, P=0.004). Logistic regression showed that: using the DBP latent classification trajectory_1 as the reference group, the OR for DBP latent classification trajectory_4 was 4.100 (95%CI: 2.571 to 6.538, P<0.001), and 2.632 (95%CI: 1.570 to 4.414, P<0.001) for DBP latent classification trajectory_2. After controlling for potential confounders (baseline BMI, being primipara or not, white blood cell counts, hemoglobin level, platelet counts and alanine aminotransferase level), the OR for DBP_traj_4 was 2.527 (95%CI: 1.534 to 4.162, P<0.001), and the OR for DBP_traj_3 was 1.297 (95%CI: 0.790 to 2.128, P=0.303), and 2.238 (95%CI: 1.328 to 3.772, P=0.002) for DBP_traj_2. Therefore, BP trajectories from 12 weeks to 28 weeks identified by LCGM served as novel risk factors that independently associated with the occurrence of preeclampsia. Receiver operating characteristic (ROC) curve analysis showed incremental diagnostic performance by combing baseline blood pressure levels with blood pressure trajectories. Conclusion: By applying LCGM, we for the first time identified distinctive BP trajectories from gestational week 12 to 28, which can independently predict the development of preeclampsia after 28 weeks of gestation.

Efficient molasses utilization for low-molecular-weight poly-γ-glutamic acid production using a novel Bacillus subtilis stain

Background

Poly-γ-glutamic acid (γ-PGA) is a biopolymer and has various applications based on its biocompatibility, non-toxicity, and edibility. Low-molecular-weight (Mw)-γ-PGA has promising applications in agriculture and pharmaceuticals. It is traditionally produced by enzymatic hydrolysis. Cost-effective bioproduction of low-Mw-γ-PGA is essential for commercial application of γ-PGA.

Results

Bacillus subtilis 242 is a newly isolated low-Mw-γ-PGA-producing strain. To develop cost-effective production of γ-PGA using this newly isolated strain, cane molasses and corn steep liquor were used to produce γ-PGA. The concentration of cane molasses was optimized and 100 g/L cane molasses resulted in high γ-PGA production. The effects of yeast extract and corn steep liquor on γ-PGA yield were investigated. High concentration of γ-PGA was obtained in the medium with corn steep liquor. A concentration of 32.14 g/L γ-PGA was achieved in fed-batch fermentation, with a productivity of 0.67 g/L/h and a percentage yield (g_γ-PGA/g_glutamate) of 106.39%. The Mw of γ-PGA was 27.99 kDa.

Conclusion

This study demonstrated the potential application of B. subtilis 242 for cost-effective production of low-Mw-γ-PGA from cane molasses.

The Impact of COVID-19 on SARSCoV-2-Negative Elderly Patients with Hip Fractures: A Single-Center Retrospective Study from Shanghai, China

Purpose

Coronavirus disease 2019 (COVID-19) has brought an unprecedented change in wellbeing globally. The spread of the pandemic reportedly reduced the incidence of activity-related trauma, while that of fragility fractures remained stable. Here, we aimed to identify the risk factors associated with the prognosis of SARS-CoV-2 negative elderly patients with hip fractures.

Patients and Methods

This retrospective study included elderly patients with hip fractures between 1st January and 9th May during the COVID-19 pandemic (Experiment group) and the same period from 2017 to 2019 (Control group). Perioperative mortality, complications, and functional recovery were compared between two groups of different time frame in the total cohort and patients who received surgical treatment. Multiple linear regression was carried out to identify the risk factors influencing the prognosis of COVID-negative elderly patients with hip fractures.

Results

The proportion of patients with admission time less than 24 hours and the 6-month postoperative Parker score were significantly decreased during COVID-19 compared with the pre-COVID-19 period (p < 0.001). Multiple linear regression demonstrated that TTA (defined as time from injury to admission), rehabilitation after discharge and outpatient follow-up were associated with the 6-month Parker score in the total population (p < 0.001) and in patients who received surgical treatment (p < 0.001).

Conclusion

Elderly patients with hip fractures had a poorer prognosis in epidemic period despite being COVID-19 negative. Factors including timely admission, postoperative follow-up, and rehabilitation could optimize safety and significantly improve the prognosis of elderly COVID-19 negative patients with hip fractures, even during a pandemic.

Associations between glucocorticoids, antiphospholipid antibodies and femur head necrosis in patients with SLE: a directed acyclic graph-based multicentre study

Background

Osteonecrosis of the femoral head (ONFH) remains a major cause of disability in patients with systemic lupus erythematosus (SLE) and seriously impairs quality of life. This study aimed to investigate associations between glucocorticoids (GCs), antiphospholipid antibodies (aPLs), and ONFH in patients with SLE.

Methods

We conducted a multicentre cohort study on patients with SLE and used a directed acyclic graph-based analysis strategy. Details of GC therapy, aPLs status, other drug administration and other SLE-related characteristics were collected. ONFH occurrence during follow-up was determined by magnetic resonance imaging. Multivariable logistic regression and generalized estimating equation models were performed to assess their effects on ONFH, and a simplified scoring system comprising these factors for short- and medium-term SLE-ONFH prediction was developed by receiver operating characteristic curve analysis.

Results

Of 449 SLE patients with a median follow-up duration of 5.3 years, 41 (9.1%) developed ONFH. Independently risk factors of SLE-ONFH including: average daily GC dose with an adjusted odds ratio (aOR) of 1.1 and 95% confidence interval (CI) of 1.0-1.1; GC therapy duration (3-5 years: aOR 3.3, 95% CI 1.4-7.8; >5 years: aOR 8.0, 95% CI 3.3-19.4); initial intravenous GC (aOR 4.4, 95% CI 1.9-10.1); positive aPLs (aOR 2.8, 95% CI 1.4-5.8); and Arterial hypertension secondary to GC usage (aOR 5.2, 95% CI 1.4-19.1). And we successfully developed the simplified scoring system (SCORE model) with an area under the curve of 0.88 (95% CI 0.82-0.94).

Conclusion

Based on the risk factors involved in the development of SLE-ONFH, a novel SCORE model was developed, which might be helpful for risk stratification of SLE-ONFH in clinical practice.

The Associations of Serum Vitamin D and Bone Turnover Markers with the Type and Severity of Hip Fractures in Older Women

Purpose

Vitamin D (25[OH]D) status and bone turnover markers (BTMs) are considered important determinants of bone quality, which is associated with the risk of hip fractures, including both femoral neck and intertrochanteric fractures, in older adults; however, the exact relationship of 25(OH)D and BTMs with the type and severity of hip fractures remains unclear and the present study aimed to identify any specific associations.

Patients and Methods

According to the inclusion and exclusion criteria, 441 older female patients with hip fractures from 2015 to 2020 and 215 women without hip fractures were included in this cross-sectional study. According to Garden and AO/OTA classifications for femoral neck and intertrochanteric fractures, patients were divided into less severe (Garden I and Garden II; 31A1) and more severe (Garden III and Garden IV; 31A2 and 31A3) fracture groups. Levels of the serum osteoblast indicator, N-terminal/mid region (N-MID); the osteoclast indicator, beta-carboxy terminal telopeptide (β-CTX); and 25(OH)D were analyzed.

Results

For patients with less severe fractures, mean 25(OH)D levels were significantly higher than those with more severe fractures (17.67 vs 15.30 ng/mL, p = 0.006). Higher 25(OH)D levels were also observed in patients with less severe intertrochanteric fractures (p = 0.01). After adjustments for confounders, 25(OH)D remained a risk factor for patients with more severe fractures (p = 0.01), particularly those with intertrochanteric fractures (p = 0.011). No significant differences in BTMS were found between patients with less severe and more severe fractures.

Conclusion

Levels of 25(OH)D were significantly associated with the severity of intertrochanteric, but not femoral neck, fractures. Neither 25(OH)D nor BTMs were associated with the type of hip fracture in older women. Separate consideration of intertrochanteric and femoral neck fractures may be appropriate when investigating the clinical association between 25(OH)D and the severity of hip fractures in older women.

[A retrospective analysis of 200-cases of otosclerosis]

Objective:To identify the audiological improvement postoperatively and improve the understand of otosclerosis for a better performance of personalized surgical treatment.Method:We retrospectively reviewed a series of 200 cases after surgery for ototsclerosis.The clinical characteristics,pre-and postoperative audiometric results,signs of Carhart notch, Gelle test and the characteristics of high-resolution computed tomography of temporal bone were analyzed retrospectively.Result:73% of patients had tinnitus, while 4% had sense of ear fullness,80.79% had Carhart notch,92.09% had negative result in Gelle test and 45.66% had positive signs on computed tomography. 68% of the patients revealed a type A tympanogram with only 22% type As.Fifty-six cases with laser stapedotomy achieved a the air bone gap at 250 Hz,500 Hz,1 kHz,2 kHz and 4 kHz of 25.54,16.25,13.75,6.34,15.96 dB,respectively. The bone conduction thresholds at 250 Hz,500 Hz,1 kHz,2 kHz improved 2.05,1.51,3.75 and 3.93 dB,respectively. At 4 kHz, bone conduction threshold increased by 1.34 dB.The improvement of bone conduction threshold at 250 Hz,1 kHz,2 kHz was significantly but for the revisions at 500 Hz and 4 kHz.Conclusion:The diagnosis of otosclerosis should be based on the combination of medical history, pure tone audiometry, tympanometry, Carhart notch, Gelle test and high resolution computed tomography of temporal bone.Surgical technique of stapedotomy with Piston artificial auditory ossicle implantation could improve not only the air conduction threshold, but also the bone conduction threshold at 250 Hz,1 kHz,2 kHz.

Exosomes Secreted from Human-Induced Pluripotent Stem Cell-Derived Mesenchymal Stem Cells Prevent Osteonecrosis of the Femoral Head by Promoting Angiogenesis

Background: Local ischemia is the main pathological performance in osteonecrosis of the femoral head (ONFH). There is currently no effective therapy to promote angiogenesis in the femoral head. Recent studies revealed that exosomes secreted by induced pluripotent stem cell-derived mesenchymal stem cells (iPS-MSC-Exos) have great therapeutic potential in ischemic tissues, but whether they could promote angiogenesis in ONFH has not been reported, and little is known regarding the underlying mechanism.

Methods: iPS-MSC-Exos were intravenously injected to a steroid-induced rat osteonecrosis model. Samples of the femoral head were obtained 3 weeks after all the injections. The effects were assessed by measuring local angiogenesis and bone loss through histological and immunohistochemical (IHC) staining, micro-CT and three-dimensional microangiography. The effects of exosomes on endothelial cells were studied through evaluations of proliferation, migration and tube-forming analyses. The expression levels of angiogenic related PI3K/Akt signaling pathway of endothelial cells were evaluated following stimulation of iPS-MSC-Exos. The promoting effects of exosomes were re-evaluated following blockade of PI3K/Akt.

Results: The in vivo study revealed that administration of iPS-MSC-Exos significantly prevented bone loss, and increased microvessel density in the femoral head compared with control group. We found that iPS-MSC-Exos significantly enhanced the proliferation, migration and tube-forming capacities of endothelial cells in vitro. iPS-MSC-Exos could activate PI3K/Akt signaling pathway in endothelial cells. Moreover, the promoting effects of iPS-MSC-Exos were abolished after blockade of PI3K/Akt on endothelial cells.

Conclusions: Our findings suggest that transplantation of iPS-MSC-Exos exerts a preventative effect on ONFH by promoting local angiogenesis and preventing bone loss. The promoting effect might be attributed to activation of the PI3K/Akt signaling pathway on endothelial cells. The data provide the first evidence for the potential of iPS-MSC-Exos in treating ONFH.

An outbreak of Candida parapsilosis fungemia among preterm infants

In this article, we describe the first outbreak of Candida parapsilosis fungemia in our hospital. We examined a cluster of four nosocomial cases of C. parapsilosis fungemia that occurred in the neonatal intensive care unit (NICU) of the Affiliated Xingtai People's Hospital of Hebei Medical University over a two-week period. We ascertained patient parameters including clinical characteristics, blood and sputum cultures, and drug sensitivity test results. Cultures from eight blood samples obtained from the four infected preterm infants showed identical characteristics and were identified as C. parapsilosis. In order to determine the infection-related factors and to control the spread of the infection among the population, we immediately initiated the emergency plan. All four of the preterm infants recovered from the infection; there were no deaths. Outbreaks of C. parapsilosis, mostly involving preterm infants of very low birth weight or extremely low birth weight, can and do occur in NICUs. Cultures prepared using multiple samples taken from different patients contribute to a more definitive diagnosis. Established measures that control and prevent the infection, as well as effective and comprehensive treatments, can lead to a favorable outcome. That is to say, improving both disinfection and isolation, as well as interrupting the pathway of transmission, is the key to controlling the spread of infection.

Treatment of aseptic nonunion after intramedullary nailing fixation with locking plate

OBJECTIVE

To evaluate the safety and efficacy of locking plate combined with bone grafting in the treatment of aseptic nonunion following intramedullary nailing fixation of fractures of the long bones.

METHODS

Thirty-eight consecutive patients treated in our hospital between January 2004 and December 2006 were included in this retrospective study. The nonunions included 20 femurs, 15 tibias, and 3 humeri. The duration of non-union ranged from 6 to 84 months and 21 (55.3%) of them were located around the metaphysis of the affected long bones. There were 12 women and 26 men with a mean age of 39.2 years (range, 9-70 years). Locking plate combined with bone grafting was the procedure chosen to treat every case of nonunion in this series. The clinical outcomes were evaluated.

RESULTS

All patients were followed up for 6-20 months (average 11.6 months). After locking plate fixation combined with bone grafting, union was achieved in all cases, the average healing time being 5.3 months (range, 4-8 months). Infection of the superficial incision occurred in three cases (7.9%) and delayed healing of the incision in one case, all of which healed with no further complications. The function of the adjacent joints was excellent to good in 30 patients (78.9%), fair in 7 (18.4%) and poor in 1 (2.6%) after follow-up.

CONCLUSION

Locking plate fixation combined with bone grafting is a highly effective treatment for aseptic nonunions of the long bones after intramedullary nailing fixation, especially in the case of metaphyseal nonunion.

Free vascularised fibular graft for post-traumatic osteonecrosis of the femoral head in teenage patients

Free vascularised fibular grafting has been reported to be successful for adult patients with osteonecrosis of the femoral head (ONFH). However, its benefit in teenage patients with post-traumatic ONFH has not been determined. We evaluated the effectiveness of free vascularised fibular grafting in the treatment of this condition in children and adolescents. We retrospectively analysed 28 hips in 28 patients in whom an osteonecrotic femoral head had been treated with free vascularised fibular grafting between 2002 and 2008. Their mean age was 16.3 years (13 to 19). The stage of the disease at time of surgery, and results of treatment including pre- and post-operative Harris hip scores, were studied. We defined clinical failure as conversion to total hip replacement. All patients were followed up for a mean of four years (2 to 7). The mean Harris hip score improved from 60.4 (37 to 84) pre-operatively to 94.2 (87 to 100) at final follow-up. At the latest follow-up we found improved or unchanged radiographs in all four initially stage II hips and in 23 of 24 stage III or IV hips. Only one hip (stage V) deteriorated. No patient underwent total hip replacement. Free vascularised fibular grafting is indicated for the treatment of post-traumatic ONFH in teenage patients.

Oriental HLA-A*11:90 detected in a Taiwanese cord blood sample and the haplotype in association with A*11:90 allele

We report here an HLA-A allele, A*11:90, found in a Taiwanese cord blood sample using DNA sequence-based typing (SBT) protocol after observing an anomalous reaction pattern in a sequence-specific oligonucleotide (SSO) typing exercise. The sequence of A*11:90 is identical to A*11:01:01, the most predominant A*11 variant in Taiwanese, in exon 2 but differs from A*11:01:01 in exon 3 by two nucleotide substitutions at codon 163 (c.487C>G and c.488G>A), resulting R163E. In comparison with the sequence of A*11:02:01, the second most predominant subtype of A*11 in Taiwanese A*11:90 has one nucleotide difference at codon 19 (c.55A>G) in exon 2 resulting K19E and two nucleotides variations at codon 163 (c.487C>G and c.488G>A) in exon 3 resulting R163E. HLA-A*11:90-B*40:02-DRB1*11:01 is the deduced probable HLA haplotype in association with A*11:90. The generation of A*11:90 is thought to involve a DNA recombination event between alleles A*11:01:01 and A*80:01 where A*80:01 donated a fragment of the DNA sequence (from n.t. 487 to n.t. 497) to the recipient sequence of A*11:01:01.

Treatment of osteonecrosis of the femoral head in lymphoma patients by free vascularised fibular grafting

The purpose of this study was to assess the outcomes of treatment of femoral head osteonecrosis using free vascularised fibular grafting in patients with Hodgkin's disease and non-Hodgkin's lymphoma. We retrospectively reviewed seven patients (14 hips) with lymphoma who underwent free vascularised fibular grafting for osteonecrosis of the femoral head, evaluating pre- and postoperative Harris hip scores, visual analog scale (VAS) pain scores, hip range of motion and radiographs. Patients were followed up for a minimum of 1.5 years (mean, 3.3 years). All these patients exhibited good recovery without severe life-threatening complications. The mean Harris hip score improved from 69 to 88, while average VAS pain score decreased from 54 to 18. At the latest follow-up, we found improvement or unchanged radiographs in all three hips with initial Steinberg stage II osteonecrosis and in nine of 11 hips with stage III or IV osteonecrosis. No hips failed treatment and underwent total hip arthroplasty. The clinical data demonstrated that free vascularised fibular grafting can slow or even halt progression of necrosis, and improve the function of the hip and quality of life in lymphoma patients.

Proteomic identification of differentially expressed proteins in curcumin-treated MCF-7 cells

Curcumin (CM), a well-known dietary pigment derived from Curcuma longa L., possess anticancer activities against a variety of tumors including human breast carcinoma. In combination with docetaxel, CM has been used in breast cancer management in the clinic. In order to explore the possible mechanism of anticancer activity of CM, in the present study, we aimed to identify proteins involved in the anticancer activity of CM in human breast cancer cell line MCF-7 using the two-dimensional electrophoresis (2-DE)-based proteomic analysis. MCF-7 cells were cultured at 37°C in an atmosphere of 5.0% CO(2). All the following experiments were repeated three times. Cell viability assay showed that after a 48-h incubation CM dose-dependently inhibited cell growth with an IC(50) value of 47.42 μM. Treatment of CM at 47.42 μM for 48 h induced apoptosis as determined by nuclear morphologic changes of Hoechst stained cells and flow cytometric analysis of Annexin V-FITC/PI stained cells. Proteomic analysis identified 12 differentially expressed proteins which contributed to multiple functional activities such as DNA transcription, mRNA splicing and translation, amino acid synthesis, protein synthesis, folding and degradation, lipid metabolism, glycolysis, and cell motility. Among them 7 proteins were up-regulated and 5 down-regulated. The up-regulated ones were verified by quantitative real-time PCR. The down-regulated proteins, TDP-43, SF2/ASF and eIF3i, as well as up-regulated ones, 3-PGDH, ERP29, and platelet-activating factor acetylhydrolase IB subunit beta positively contribute to the anticancer activity of CM in MCF-7 cells. These molecules are implicated in the bioactivities of CM for the first time. The findings of this study would shed new insights for systematically understanding the mechanisms of CM in breast cancer intervention.

[Assessment study on a set of platelet-rich plasma preparation]

OBJECTIVE

To calculate the recovery rate and enrichment factor and to analyse the correlation by measuring the concentrations of platelets, leukocyte, and growth factors in platelet-rich plasma (PRP) so as to evaluate the feasibility and stability of a set of PRP preparation.

METHODS

The peripheral blood (40 mL) was collected from 30 volunteers accorded with the inclusion criteria, and then 4 mL PRP was prepared using the package produced by Shandong Weigao Group Medical Polymer Company Limited. Automatic hematology analyzer was used to count the concentrations of platelets and leukocyte in whole blood and PRP. The enrichment factor and recovery rate of platelets or leukocyte were calculated; the platelet and leukocyte concentrations of male and female volunteers were measured, respectively. The concentrations of platelet-derived growth factor (PDGF), transforming growth factor beta (TGF-beta), and vascular endothelial growth factor (VEGF) were assayed by ELISA.

RESULTS

The platelet concentrations of whole blood and PRP were (131.40 +/- 29.44) x 10(9)/L and (819.47 +/- 136.32) x 10(9)/L, respectively, showing significant difference (t = 27.020, P = 0.000). The recovery rate of platelets was 60.85% +/- 8.97%, and the enrichment factor was 6.40 +/- 1.06. The leukocyte concentrations of whole blood and PRP were (5.57 +/- 1.91) x 10(12)/L and (32.20 +/- 10.42) x 10(12)/L, respectively, showing significant difference (t = 13.780, P = 0.000). The recovery rate of leukocyte was 58.30% +/- 19.24%, and the enrichment factor was 6.10 +/- 1.93. The concentrations of platelets and leukocyte in PRP were positively correlated with the platelet concentration (r = 0.652, P = 0.000) and leukocyte concentration (r = 0.460, P = 0.011) in whole blood. The concentrations of platelet and leukocyte in PRP between male and female were not significantly different (P > 0.05). The concentrations of PDGF, TGF-beta, and VEGF in PRP were (698.15 +/- 64.48), (681.36 +/- 65.90), and (1071.55 +/- 106.04) ng/mL, which were (5.67 +/- 1.18), (6.99 +/- 0.61), and (5.74 +/- 0.83) times higher than those in the whole blood, respectively. PDGF concentration (r = 0.832, P = 0.020), TGF-beta concentration (r = 0.835, P = 0.019), and VEGF concentration (r = 0.824, P = 0.023) in PRP were positively correlated with platelet concentration of PRP.

CONCLUSION

PRP with high concentrations of platelets, white blood cells and growth factors can be prepared stably by this package.

Beneficial effect of autologous transplantation of endothelial progenitor cells on steroid-induced femoral head osteonecrosis in rabbits

Femoral head osteonecrosis (ON) is a serious complication of steroid administration. We examined whether implantation of autologous bone marrow-derived endothelial progenitor cells (EPCs) can augment neovascularization and bone regeneration in steroid-induced osteonecrosis of the femoral head. Forty 12-week-old male New-Zealand white rabbits were divided into group I (left untreated, n=12), group II (core decompression, n=12), and group III (core decompression + autologous EPCs implantation, n=16) after receiving an established inductive protocol for inducing steroid-associated ON. Four weeks later, these rabbits were euthanized, bilateral femora were dissected for Micro-CT-based microangiography to assess vascularization, and then the osteonecrotic changes and repair processes were examined histopathologically. Quantitative analysis showed that new vessel formation in group III was significantly greater compared with other groups at 4 weeks after treatment. The histologic and histomorphometric analyses revealed that the new bone volume was significantly higher in group III than in groups I and II 4 weeks after treatment. A combination of EPCs and core decompression enhances the neovascularization and bone regeneration in rabbit steroid-induced femoral head ON. Local implantation of EPCs may provide a novel and effective therapeutic option for early corticosteroid-induced ON.

Reverse LISS plating for intertrochanteric hip fractures in elderly patients

Background

Fractures of the intertrochanteric hip are common and the treatment of unstable fractures generally requires an operative approach. In elderly patients, osteoporosis makes internal fixation problematic and frequently contributes to failed fixation and poor clinical results. We have attempted to apply the Less Invasive Stabilization System (LISS) in reverse position for the repair of intertrochanteric hip fractures in elderly patients with osteoporotic bones. A retrospective review is presented of the cases of 28 elderly patients with stable and unstable fractures of the intertrochanteric hip treated using the reverse LISS.

Methods

We treated 28 elderly patients with a mean age of 82.3 years. According to the Evens classification, there were 2 Type I fractures, 2 Type II fractures, 3 Type III fractures, 13 Type IV fractures, 6 Type V fractures and 2 Type R fractures. All fractures were treated using the reverse LISS. Radiographic and clinical evidence of functional outcome and complications were evaluated.

Results

Mean perioperative blood loss was 92.4 milliliters (range 35 to 245 milliliters), and the mean postoperative hospital stay was 8.7 days (range 3 to 14 days).

Complications included one minor wound hematoma. Radiographically, no collapses, screw cutouts, or head penetrations were seen. All surviving patients (28 of 28; 100 percent) had uneventful fracture healing with union achieved by six months in all patients.

Conclusions

Use of the Reverse LISS plating for intertrochanteric hip fractures resulted in event-free fracture healing.

Changes in Femoral Head Blood Supply and Vascular Endothelial Growth Factor in Rabbits with Steroid-induced Osteonecrosis

The molecular aetiology of steroid-induced osteonecrosis (ON) is unclear. The aim of this study was to investigate changes in the femoral head blood supply and vascular endothelial growth factor (VEGF) protein levels following steroid-induced ON of rabbit femoral heads in the early stage of the disease, and to investigate a possible mechanism for ON. Using a classic protocol, ON was induced in 30 male 28-week old New Zealand white rabbits. An additional 15 untreated rabbits served as controls. Change of blood supply in the proximal femur was assessed by dynamic magnetic resonance imaging and microangiography. The VEGF protein and mRNA levels were assessed by immunohistochemistry and quantitative real-time polymerase chain reaction, respectively. After 6 weeks, the results indicated that VEGF protein and mRNA levels were significantly lower and femoral head blood supply had also decreased significantly in ON+ rabbits compared with controls. The down-regulation of VEGF may play a critical role in the disease process of ON.

Treatment of femoral head osteonecrosis in patients with systemic lupus erythematosus by free vascularised fibular grafting

The purpose of this study was to review the radiographs of symptomatic femoral head osteonecrosis in patients with systemic lupus erythematosus (SLE) and to assess the results of treatment using free vascularised fibular grafting. We retrospectively reviewed 50 patients (80 hips) with SLE who underwent free vascularised fibular grafting for osteonecrosis of the femoral head. All patients were followed up for at least 2 or more years (average, 4.3 years). The mean Harris hip score improved from 72 to 88. At the latest follow-up, we found improved or unchanged radiographs in 12 of initially Stage II hips and in 60 of 64 Stage III or IV hips. No hips failed treatment and underwent total hip arthroplasty. The data suggest that free vascularised fibular grafting was successful in maintaining joint function and in delaying the need for joint replacement procedure.

Free vascularised fibular grafting with OsteoSet®2 demineralised bone matrix versus autograft for large osteonecrotic lesions of the femoral head

The aim of this study was to compare the safety and efficacy of OsteoSet®2 DBM with autologous cancellous bone in free vascularised fibular grafting for the treatment of large osteonecrotic lesions of the femoral head. Twenty-four patients (30 hips) with large osteonecrotic lesions of the femoral head (stage IIC in six hips, stage IIIC in 14, and stage IVC in ten, according to the classification system of Steinberg et al.) underwent free vascularised fibular grafting with OsteoSet®2 DBM. This group was retrospectively matched to a group of 24 patients (30 hips) who underwent free vascularised fibular grafting with autologous cancellous bone during the same time period according to the aetiology, stage, and size of the lesion and the mean preoperative Harris hip score. A prospective case-controlled study was then performed with a mean follow-up duration of 26 months. The results show no statistically significant differences between the two groups in overall clinical outcome or the radiographic assessment. Furthermore, no adverse events related to the use of the OsteoSet®2 DBM were observed. The results demonstrate that OsteoSet®2 DBM combined with autograft bone performs equally as well as that of autologous bone alone. Therefore, OsteoSet®2 DBM can be used as a safe and effective graft extender in free vascularised fibular grafting for large osteonecrotic lesions of the femoral head.

Curative effect and safety of vascularized fibula grafting in renal transplant recipients with osteonecrosis of the femoral head: three case reports

Osteonecrosis of the femoral head is a common and severe complication after renal transplantation. It is characterized by deterioration of hip joint function, which impairs quality of life. We present 3 renal transplant case reports of patients with osteonecrosis of the femoral head who underwent free vascularized fibular grafting at our hospital. Follow-up was from 1(1/2) to 2 years. All 3 patients exhibited good recovery with substantial improvement in joint function. Intraoperative and postoperative findings demonstrated the safety of this surgical procedure.

The regenerative effect of platelet-rich plasma on healing in large osteochondral defects

Platelet-rich plasma (PRP), a platelet concentrate made of autogenous blood, has been used to improve bone and soft tissue defect healing in recent years. The aim of this study was to assess the effect of PRP on articular cartilage defects in a rabbit model. Forty-eight osteochondral defects created in the femoropatellar groove were (a) left untreated, (b) treated with autogenous PRP in a poly-lactic-glycolic acid (PLGA), or (c) with PLGA alone. Platelets were enriched 5.12-fold compared to normal blood in the PRP. After four and 12 weeks, the explanted tissue specimens were assessed by macroscopic examination, micro-computed tomography, and histological evaluation. Macroscopic examination, micro-computed tomography and histology of the newly formed cartilage and bone in the defect differ significantly between the PRP-treated and the untreated groups, and stimulatory effect of PRP on osteochondral formation was observed. In conclusion, PRP in PLGA improves osteochondral healing in a rabbit model.

The effect of grain size of rock phosphate amendment on metal immobilization in contaminated soils

When rock phosphates (RP) are used to remediate Pb-contaminated soils, their effectiveness is likely affected by their grain size. In this study, the effect of grain size of rock phosphate on the effectiveness of heavy metal immobilization in two contaminated soils was measured in pot experiment. Rock phosphate was used with four different grain sizes: <35, 35-72, 72-133 and 133-266microm. The application rate of rock phosphate in two soils was determined based on P/metals (Pb, Zn, Cu and Cd) molar ratio of 5.0 in the soils. The results showed that rock phosphate of the smallest grain size (<35microm) was superior to all of other grain sizes more than 35microm for reducing uptake in plant (Brassica oleracea L.) shoots for Cd (19.6-50.0%), Pb (21.9-51.4%) and Zn (22.4-34.6%), respectively, as compared with the soil without application of rock phosphate. Sequential extraction analysis indicated that rock phosphate was most effective for soil Pb to induced transformation from non-residual fractions to a residual fraction than that for Zn and Cd. Such transformation was probably through dissolution of Pb associated with exchangeable (EX), organic fraction (OC), acidic fraction (AC) and amorphous Fe and Al oxides-bound (OX) fraction and precipitation of pyromorphite-like minerals. Results suggested that the rock phosphate with small grain size was superior to that with large grain size for in situ remediation technology.

Soil to plant transfer of 238U, 226Ra and 232Th on a uranium mining-impacted soil from southeastern China

Both soil and plant samples of nine different plant species grown in soils from southeastern China contaminated with uranium mine tailings were analyzed for the plant uptake and translocation of 238U, 226Ra and 232Th. Substantial differences were observed in the soil-plant transfer factor (TF) among these radionuclides and plant species. Lupine (Lupinus albus) exhibited the highest uptake of 238U (TF value of 3.7x10(-2)), while Chinese mustard (Brassica chinensis) had the least (0.5x10(-2)). However, in the case of 226Ra and 232Th, the highest TFs were observed for white clover (Trifolium pratense) (3.4x10(-2)) and ryegrass (Lolium perenne) (2.1x10(-3)), respectively. 232Th in the tailings/soil mixture was less available for plant uptake than 226Ra or 238U, and this was especially evident for Chinese mustard and corn (Zea mays). The root/shoot (R/S) ratios obtained for different plants and radionuclides shown that Indian mustard had the smallest R/S ratios for both 226Ra (5.3+/-1.2) and 232Th (5.3+/-1.7), while the smallest R/S ratio for 238U was observed in clover (2.8+/-0.9).

Surfactant free fabrication of polymeric nanoparticles by combined liquid–liquid phase separation and solvent/nonsolvent mixing technology

It is generally agreed that, in most cases, surfactants are required to obtain stable polymeric nanoparticle dispersions. Here, we report a method which can be used to produce surfactant free yet stable polymeric nanoparticle dispersions. This method is based on explored mechanism of selective solvation of nanoparticles and EPD (electron pair donor)/EPA (electron pair acceptor) complexes formed among solvent and nonsolvent molecules. Using polyimide P84 (copolyimide 3,3(') 4,4(')-benzophenone tetracarboxylic dianhydride and 80% methylphenylene diamine+20% methylene dianiline) as the model polymer, this mechanism was realized through a combined liquid-liquid phase separation and solvent/nonsolvent mixing technology. Surfactant-free polyimide nanoparticles (<100 nm) were produced. Experimental details and principles of this technology were given based on the ternary diffusion, the liquid-liquid phase separation and the advanced nucleation and growth theory. Two types of methods [denoted as the forward titration method and the backward titration (BT) method] were examined. It was found that the BT method is extremely helpful to prepare polyimide nanoparticles (<100 nm). As another important aspect, explored stabilization mechanism of the resultant nanoparticle dispersions was supported by the comparative experiments, implying that selective solvation of nanoparticles and EPD/EPA complexes may play key roles in stabilization.

Rapid screening with a recombinant antigen (rK39) for diagnosis of visceral leishmaniasis using dipstick

OBJECTIVE

To evaluate the diagnostic value of the recombinant antigen of 39 amino acid repeats encoded by a kinesin-like gene of Leishmania changasi (rK39) in serodiagnosis of visceral leishmaniasis (VL).

METHODS

In Kashi, Xinjiang, 13 VL patients with splenomegaly and bone marrow aspirate culture positive were subjected to dipstick assay. A drop of whole blood or serum from patient was placed at the absorbing pad at the bottom of the dipstick. Flooding of the bottom protein with buffer allows serum proteins to migrate upwards, producing the positive band and Western blot analysis of rK39 subsequently performed with the sera collected.

RESULTS

The end-point titers of anti-rK39 antibodies of these sera were determined by ELISA and found to fall within the range of 10(-2) to 10(-4), which were consistent with the intensity of their reaction with rK39 in dipstick assay. The positive sera could also recognize the specific rK39 band as analyzed by Western blot analysis.

CONCLUSION

The rK39 dipstick assay is more rapid, specific, sensitive and less invasive than the conventional methods of diagnosis for VL in the areas of low endemicity.

Effect of bilateral testicular resection on thymocyte and its microenvironment in aged mice

AIM

To observe the changes in thymocyte and its microenvironment in aged mice after bilateral testicular resection.

METHODS

In male old mice, at the 25th day after testicular resection, the peripheral blood and thymus were collected. Blood and thymus suspension smears were prepared for quantitative histochemistry and immunohistochemistry study under light and electron microscopes.

RESULTS

In testes resected mice the size and the weight of thymus were markedly increased. The demarcation between cortex and medulla was clear. The cortex was thickened and the cell density was increased. The ratio of cortex/medulla stereometry was increased. The total cell count, thymocyte count, the percentage of acid alpha-naphthyl acetate esterase (ANAE) positive thymocytes, nonlymphocytes and the rosette formation of macrophages and thymocytes were all increased. The thymocytes surrounded closely to the light thymic epithelial cells, dendritic cells or macrophages. The lymphocytes, particularly the ANAE positive lymphocytes of peripheral blood were increased.

CONCLUSION

After bilateral testicular resection, the thymus of aged male mice showed morphological regeneration and the thymocytes and its microenvironment appeared to be definitely improved. It is suggested that testicular resection may improve immune function.

A novel cloud-point extraction process for preconcentrating selected polycyclic aromatic hydrocarbons in aqueous solution

A novel but simple cloud-point extraction (CPE) process is developed to preconcentrate the trace of selected polycyclic aromatic hydrocarbons (PAHs) with the use of the readily biodegradable nonionic surfactant Tergitol 15-S-7 as extractant. The concentrations of PAHs, mixtures of naphthalene and phenanthrene as well as pyrene, in the spiked samples were determined with the new CPE process at ambient temperature (23 degrees C) followed by high performance liquid chromatography(HPLC) with fluorescence detection. More than 80% of phenanthrene and pyrene, respectively, and 96% of naphthalene initially present in the aqueous solutions with concentrations near or below their aqueous solubilities were recovered using this new CPE process. Importantly Tergitol 15-S-7 does not give any fluorometric signal to interfere with fluorescence detection of PAHs in the UV range. No special washing step is, thus, required to remove surfactant before HPLC analyses. Different experimental conditions were studied. The optimum conditions for the preconcentration and determination of these selected PAHs at ambient temperature have been established as the following: (1) 3 wt% surfactant; (2) addition of 0.5 M Na2SO4; (3) 10 min for equilibration time; and (4) 3000 rpm for centrifugal speed with duration of 10 min.

[Studies on the chemical constituents from Aquilegia ecalcarata Maxim]

OBJECTIVE

To study the chemical constituents from Aquilegia ecalcarata.

METHOD

Compounds were isolated with silica gel and polyamide chromatography and their structures were determined by spectral analysis and chemical evidence.

RESULT

Five compounds were obtained and identified as beta-sitosterol, isoorientin-7-O-glucoside, isovitexin-4'-O-glucoside, isovitexin-2'-O-rhamnoside, luteolin-7-O-glucoside.

CONCLUSION

All the compounds were isolated from this plant for the first time.

Translation drag coefficient of a self-similar assembly of spheres immersed in an incompressible fluid

On the basis of deterministic fractals and the Rotne-Prager hydrodynamic interaction tensor, we confirm the asymptotic as well as the finite size scaling of the friction coefficient lambda of a self-similar structure. The fractal assembly is made of N spheres with its dimension varying from D < 1 to D = 3. The number of spheres can be as high as N approximately O(10(4)). The asymptotic scaling behavior of the friction coefficient per sphere is lambda approximately N(1/D-1) for D > 1, lambda approximately (lnN)(-1) for D = 1, and lambda approximately N(0) for D < 1. The crossover behavior indicates that while in the regime of D > 1 the hydrodynamic screening effect grows with the size, for D<1 it is limited in a finite range, which decays with decreasing D.

Aquiledine and isoaquiledine, novel flavonoid alkaloids from Aquilegia ecalcarata

Two new flavonoid alkaloids, aquiledine (1) and isoaquiledine (2), were isolated from the whole herb of Aquilegia ecalcarata, and their structures were determined by detailed spectral analysis. Three known flavonoids were also isolated from this extract-apigenin, apigenin-7,4'-dimethyl ether, and luteolin-and have not been reported previously from A. ecalcarata.

Faxen's Laws of a Composite Sphere under Creeping Flow Conditions

Under creeping flow conditions, Faxen's laws are derived for a composite sphere comprising a solid core covered by a permeable layer of arbitrary thickness. The derivations are carried out by applying reciprocal theorem in combination with fluid velocity and pressure distributions in certain simple flow as a comparison field. In this regard, the fluid velocity disturbances caused by a composite sphere subject to a simple shear flow and a rotational flow are solved individually. In the limiting case where the solid core vanishes, the resulting Faxen expressions for the drag force, torque, and stresslet compare very well with the existing Faxen's law for a porous sphere. It is found that when the porous layer is thick enough and its permeability is sufficiently low, the hydrodynamic behavior of a composite sphere can be approximated by that of a porous particle with equal permeability. This can be explained by the fact that the fluid cannot penetrate deeply into a porous layer of low permeability to flow through the pores near the core surface, and thereby the fluid can hardly feel the resistance from the core surface. Copyright 2000 Academic Press.

Hydrodynamic Interactions and Mean Settling Velocity of Porous Particles in a Dilute Suspension

A theoretical investigation is conducted to study hydrodynamic interactions among porous spheres under creeping flow conditions. The particles may differ in size and permeability. Based on the Brinkman equation governing the fluid flow inside the particle, the flow field, and the drag force and torque on the particle are calculated numerically using a boundary collocation method. The results show that the hydrodynamic interaction increases with decreasing permeability. An important feature is that unlike the singular force and torque for two touching identical impermeable spheres undergoing certain motions with planar symmetry, the force and torque always remain finite for the case of two porous spheres. Using the resulting hydrodynamic interactions, the average sedimentation velocity of porous spheres suspended in a bounded fluid is also evaluated to determine the leading order effect of the particle concentration. Because of weaker hydrodynamic interactions among porous spheres, the hindrance coefficient is smaller than that for impermeable particles. When the porous spheres carry charge, the hindrance effect is augmented by increasing the double layer thickness. Copyright 1999 Academic Press.

Electrostatic Interaction and Hindered Diffusion of Ion-Penetrable Spheres in a Slit Pore

Electrostatic interaction and hindered diffusion of ion-penetrable spheres in a slit pore filled with an electrolyte solution are investigated theoretically. The concentration of the particles is assumed sufficiently low so that the interactions between the particles can be neglected. The slit pore comprises two parallel infinite plates, which can be either permeable or impermeable to the electrolyte. The electrostatic interaction energy is obtained analytically by adopting an integral of Green's function and an image method. It is found that for impermeable plates having constant surface charge densities, the electrostatic interaction can be attractive or repulsive for a particle with charge of opposite sign, depending on the relative magnitudes of charge densities and particle location. Similar behavior is predicted for plates with constant surface potential and a particle with charge of like sign. The interaction energy is used to determine the spatial distribution of the particle in the pore and the partition coefficient, and then to calculate the average and apparent diffusivities. The average diffusivity calculated from the average mobility in the pore is always smaller than that in the bulk solution because of greater drag the particle experiences in the presence of the plates. This mean diffusivity is larger than that in the corresponding neutral system for repulsive electrostatic interaction, but becomes smaller for attractive interaction. The apparent diffusivity defined from the flux based on the bulk concentration of the particle depends strongly on the ion concentration, as does the partition coefficient when the double layer is sufficiently thick. Copyright 1998 Academic Press.

Advantages of laparoscopic splenectomy for splenomegaly due to hematologic diseases

Recent advancements in laparoscopic surgery have made laparoscopic splenectomy possible. We retrospectively compared the outcomes of laparoscopic versus open splenectomy in patients with idiopathic thrombocytopenic purpura (ITP) or beta-thalassemia. From July 1993 to July 1997, 52 patients (ITP, 43 cases; beta-thalassemia, 9 cases) underwent either laparoscopic (30 patients, 9 men, 21 women; average age, 36.9 years) or conventional open splenectomy (22 patients, 5 men, 17 women; average age, 34.3 years). The two groups were similar in terms of sex, age, diagnosis, duration of disease, preoperative platelet count, and spleen size. The mean surgical time, estimated amount of blood loss, duration of postoperative recovery, analgesic usage, and complications were compared between the two groups. Laparoscopic splenectomy was successful in 29 (97%) of the 30 patients. The mean surgical time in the laparoscopy group was longer than in the open splenectomy group (190.6 vs 113.9 minutes, p < 0.01). The laparoscopy group had earlier postoperative oral intake (15.2 vs 52.6 hours, p < 0.01), less usage of analgesics (meperidine 50 mg/unit, 1.1 vs 2.8 units, p < 0.01) and a shorter postoperative hospital stay (4.1 vs 6.8 days, p < 0.01). The estimated blood loss, incidence of accessory spleen, surgical complication rate, and recurrence rate of thrombocytopenia were similar in the two groups. Our findings show that laparoscopic splenectomy in patients with ITP or beta-thalassemia is as safe as the open approach. While laparoscopy required a longer surgical time, the recovery period was shorter, analgesic use was less, and physical discomfort was less severe.

Women's health in the People's Republic of China: some challenges of modernization

OBJECTIVE

To identify aspects of the health of Chinese women throughout their lifespan which may paradoxically be threatened by modernization and to suggest relevant interventions through medical practice, education and research to meet these challenges.

DATA SOURCES

Six risk areas were selected as examples: infant sex ratios; tobacco use by girls; respiratory illness plus anemia; psychosocial stress; osteoporosis; and dementia. Articles and other databases, through article citations, and through consultations with Chinese medical professionals.

DATA SELECTION

Studies were selected which described clinical investigations, health care policy, or conditions of women in the People's Republic of China (PRC). Preference (but not exclusivity) was given to articles in internationally available publications, in English, and to authors working in the PRC.

DATA EXTRACTION

Study quality, specific descriptive information concerning population, samples, and outcome measures were evaluated.

DATA SYNTHESIS

Data documenting the present and future significance of these health threats are described, and current and potential interventions to address these problems through medical practice, education and research are outlined.

CONCLUSION

Important issues in women's health are currently recognized in the PRC; problems occur in assigning priorities in the face of a large population and limited resources. The Chinese medical community plays a central role in developing and carrying out interventions to protect and promote women's health.

Self-learning fuzzy neural networks for control of uncertain systems with time delays

We address the problem of control of uncertain systems with time delays. Using the fuzzy logic control and artificial neural network methodologies, we present a self-learning fuzzy neural control scheme for general uncertain processes. In this scheme, a neural network compensator is designed instead of the classical Smith predictor for attenuating the adverse effects of time delays of the uncertain systems. The scheme has been used in control of welding pool dynamics of the arc welding process, and the experiment results show the control scheme available.

International access to the Chinese medical literature through MEDLINE

This article reviews, for authors publishing in the Chinese literature, the characteristics of MEDLINE users, the format of MEDLINE citations and the main retrieval strategies used with the system. References were retrieved and data collected through MEDLINE searches of the database 1988-June 1992. Thirty-six indexed journals from the People's Republic of China (PRC) were analyzed. The items of a MEDLINE citation are described. Titles of Chinese journals are listed in English as well as Chinese in the annual "List of Serials Indexed" of Index Medicus. Articles from journals in the PRC are indexed at the China MEDLARS Center, Beijing, PRC. For the 36 journals analyzed, 12,530 citations appeared in MEDLINE during the search period. Basic search strategies are described. Users doing author searches may have difficulties with common Chinese surnames, especially if only one given name initial is used. Journal searches of specialty journals, as well as address field searches for publications from a particular institution, may be helpful to scientists planning a visit to China. Effective use of MEDLINE has become an opportunity and responsibility for scientists and physicians over the world. Suggestions for preparation of English titles and abstracts to assure optimal information transfer and retrieval efficiency are: think about your audience; do not waste words; include key features in the title; be consistent with names and affiliations; use MeSH terms; include important non-MeSH terms in text; use structured abstracts; and obtain MEDLINE printouts of your own citations.

[Diagnostic value of serum CA 19-9 determination in digestive tract cancer]

Serum carbohydrate antigen CA 19-9 level was measured by radioimmunoassay in 55 patients with malignant digestive disease (14 esophageal cancers, 11 gastric cancers, 5 colorectal cancers, 14 primary liver cancers and 11 pancreatic cancers). The mean value of serum CA 19-9 levels was 22.11 +/- 24.79 u/ml in esophageal cancer, 99.91 +/- 100.12 u/ml in gastric cancer, 64.5 +/- 53.43 u/ml in colorectal carcinoma, 47.81 +/- 68.62 u/ml in primary hepatic cancer and 459.55 +/- 696.76 u/ml in pancreatic cancer (CA 19-9 greater than 37 mu/ml as positive). There were significant differences (P less than 0.05) between the mean serum CA 19-9 levels of pancreatic cancer and esophageal cancer, primary hepatic cancer. An increased CA 19-9 synthesis and excretion by tumor cells or increased pressure on pancreatic duct by the tumor may cause the elevation of serum CA 19-9 level in cancer patients. The authors conclude that CA19-9 is a valuable tumor marker in the diagnosis of pancreatic cancer and, probably, other gastrointestinal tumors.

Use of serum and vaccine in combination for prophylaxis following exposure to rabies

Persons seriously wounded by rabid animals in China were administered postexposure rabies treatment with serum and vaccine. Some of these exposures were similar to those described in an attack by a rabid wolf in Iran in 1954, in which some persons developed rabies. Postexposure treatment consisted of the administration of primary hamster kidney cell rabies vaccine and purified equine antirabies serum. Persons with severe wounds from the bites of rabid animals survived without sequelae when the serum and vaccine were administered together within 3 days of the bite, and persons with superficial exposures survived after treatment with vaccine alone. Serum neutralizing antibodies were present 1 year after the patients had received a full course of treatment. Some persons with severe wounds who had not received antiserum and vaccine died of rabies.