[Efficacy and safety of half-dose rituximab in the treatment of 23 cases with lupus nephritis].

The study aimed to analyze the efficacy and safety of rituximab in the treatment of 23 cases of lupus nephritis and explore the prospect of half-dose rituximab in lupus nephritis treatment. Twenty-three patients with lupus nephritis hospitalized in the Department of Rheumatology and Immunology at the First Medical Center of the PLA General Hospital from May 2013 to December 2021 were selected. Eighteen patients received rituximab 375 mg/m2 on the first and 14th days, 5 patients received 500 mg of rituximab on the first and 14th days, and rituximab was used as needed 6 months later. Methylprednisolone (80-120 mg) was given together with rituximab. Afterward, 1 mg/kg prednisone was used for 4 weeks, which was progressively tapered to maintenance doses or discontinued. B lymphocyte level, renal function, 24-h urine protein level, and systemic lupus erythematosus (SLE) disease activity index 2000 (SLEDAI2K) score before and after treatment were recorded. The efficacy and adverse reactions were analyzed. The results showed that 11 patients suffered from renal insufficiency [creatinine (162.7±58.6) µmol/L ] at baseline, while the creatinine level of 9 patients returned to normal 12 months after the treatment [ (66.3±10.1)µmol/L ]. Normal renal function of the other 12 patients was maintained during treatment. After 12 months, the 24-h urine protein level decreased from 4.00 (2.00,6.80) g in the baseline period to 0.10 (0.08,0.40) g. SLEDAI2K score decreased from 22 (18,26) in the baseline period to 3 (0,6) 12 months after the treatment. The B lymphocyte level reached 0.00 (0.00,0.01)% at 3 months. Of 23 patients, 13 patients achieved complete remission, and 7 patients achieved partial remission after 6 months of rituximab treatment. Five patients experienced adverse reactions related to rituximab, including 1 case of transfusion reaction, 1 case of perioral herpes with pulmonary infection, and 3 cases of decreased IgG levels. Therefore, rituximab regimen used in this study can be an effective treatment strategy for lupus nephritis.

[Comparison of the accuracy of intraocular lens power calculation formulas based on the new swept-source optical coherence tomography biometry].

Objective: To compare the accuracy of 6 intraocular lens power calculation formulas based on the new swept-source optical coherence tomography biometry and to analyze the prediction error. Methods: Retrospective case series study. Clinical data were collected from 599 patients (599 eyes) who had underwent uncomplicated phacoemulsification and the IOLMaster 700 examination at the Eye Hospital of Wenzhou Medical University between November 2018 and November 2019. Among the patients, there were 208 males and 391 females with an age of (69±10) years. According to the axial length (AL), eyes were divided into the short AL group (≤22.5 mm, n=100), the normal AL group (>22.5 mm and<25.5 mm, n=375); and the long AL group (≥25.5 mm, n=124). Eyes were also grouped based on the mean keratometry (Km) as flat (≤42.00 D, n=47), normal (>42.00 D to<46.00 D, n=461), and steep (≥46.00 D, n=91), and by anterior chamber depth (ACD) as shallow (≤2.5 mm, n=71), normal (>2.5 mm to<3.5 mm, n=436), and deep (≥3.5 mm, n=92). The median absolute errors (MedAEs) of the Barrett Universal Ⅱ, Haigis, Hoffer Q, Holladay Ⅰ, Holladay Ⅱ, and SRK/T formulas in different AL, Km, and ACD groups were compared using the Friedman test. Results: The differences in MedAE among the 6 formulas of 599 patients (599 eyes) were statistically significant (χ²=120.549, P<0.001). The MedAE of the Barrett Universal Ⅱ formula was smallest (0.35 D), followed by the SRK/T formula (0.36 D). There was no significant difference between the MedAEs of the Barrett universal Ⅱ and Haigis, SRK/T formula (all P=1.000), but there were statistically significant differences among the other formulas (all P<0.01). In different AL groups, the MedAE of each formula was statistically different (χ²=38.307, 38.779, 112.997; all P<0.01).The Barrett Universal Ⅱ formula resulted in the lowest MedAE in the short AL group (0.40 D) and the long AL group (0.31 D). The MedAE of the SRK/T in the normal AL group was lowest (0.35 D). The 6 formulas showed significant differences in MedAE values in different Km groups (χ²=12.284, 90.924, 39.387; all P<0.05).The Haigis formula achieved the lowest MedAE in the flat Km group (0.26 D) and the steep Km group (0.34 D). The Barrett UniversalⅡ formula achieved the lowest MedAE in the normal Km group (0.33 D). The differences in MedAE values of the 6 formulas in different ACD groups were statistically significant (χ²=37.389, 57.643, 52.845; all P<0.01), and the MedAE values of the Barrett Universal Ⅱ in different ACD groups were smallest (0.46, 0.33, 0.31 D). Conclusions: The Barrett Universal Ⅱ formula perform the best over the entire AL range, followed by the Haigis and SRK/T formulas. The Barrett Universal Ⅱ formula result in the lowest prediction error in the short AL group, the long AL group, and all ACD groups. The Haigis formula may be more accurate when the Km was ≤42.00 D or ≥46.00 D. (Chin J Ophthalmol, 2021, 57: 502-511).

[Application and influencing factors of endorectal ultrasound in T-stage restaging of rectal cancer following neoadjuvant therapy].

Objective: To evaluate the accuracy and influencing factors of T-stage restaging of rectal cancer following neoadjuvant therapy with endorectal ultrasonography (ERUS). Methods: In a retrospective study, endorectal ultrasound was performed in 86 patients with rectal cancer following neoadjuvant therapy. The imaging results were compared with postoperative pathological T-stage. Results: The accuracy of overall T-stage restaging with ERUS was 67.4% (58/86). Additionally, the accuracy of restaging in middle and high rectal cancer was higher, with an accuracy of 76.1%(35/46)and 100%(4/4) respectively. Univariate analysis showed that the location of tumors was an independent factor affecting the accuracy of ERUS(P=0.033). Conclusion: ERUS is an effective method to restage T-stage of rectal cancer following neoadjuvant therapy.

Evidence for Secondary Flux Rope Generated by the Electron Kelvin-Helmholtz Instability in a Magnetic Reconnection Diffusion Region.

Secondary flux ropes are suggested to play important roles in energy dissipation and particle acceleration during magnetic reconnection. However, their generation mechanism is not fully understood. In this Letter, we present the first direct evidence that a secondary flux rope was generated due to the evolution of an electron vortex, which was driven by the electron Kelvin-Helmholtz instability in an ion diffusion region as observed by the Magnetospheric Multiscale mission. The subion scale (less than the ion inertial length) flux rope was embedded within the electron vortex, which contained a secondary electron diffusion region at the trailing edge of the flux rope. We propose that intense electron shear flow produced by reconnection generated the electron Kelvin-Helmholtz vortex, which induced a secondary reconnection in the exhaust of the primary X line and then led to the formation of the flux rope. This result strongly suggests that secondary electron Kelvin-Helmholtz instability is important for reconnection dynamics.

[The safety and efficacy of golimumab in treatment of 25 patients with active ankylosing spondylitis].

Objective: To evaluate the efficacy and safety of golimumab in patients with active ankylosing spondylitis (AS). Methods: This was a randomized, double-blind, placebo-controlled trial. The subjects were randomized to receive either golimumab 50mg subcutaneously or placebo every 4 weeks. Patients in both groups received golimumab 50mg from week 24 to week 48. The primary endpoint was the proportion of at least 20% improvement in the Assessment of Spondyloarthritis International Society (ASAS20) at week 14. The secondary endpoints included at least 40% improvement in the Assessment of Spondyloarthritis International Society (ASAS40), ASAS partial-remission, Bath AS functional index, Bath AS disease activity index, Bath AS metrology index, enthesitis index and Jenkins sleep evaluation questionnaire. Results: A total of 25 subjects were included in this study, 13 with golimumab and 12 with placebo. At Week 14, 6(46.2%) subjects achieved ASAS20 in golimumab group and 2(16.7%) in placebo group. Significant improvements of other efficacy endpoints were also found in golimumab group. Golimumab was safe and well to lerated. Most of the adverse events were slightly impaired liver function, where as elevated aspartate aminotransferase and/or alanine aminotransferase returned to normal without drug with drawal. Conclusion: Golimumab improves AS activity, clinical symptoms and sleep disturbance in patients with active AS with good safety and tolerability.

[Value of dual contrast-enhanced ultrasound in the preoperative T staging of rectal carcinoma].

Objective: To explore the value of dual contrast-enhanced ultrasound in preoperative T staging of rectal carcinoma. Methods: Dual contrast-enhanced ultrasound examinations were performed on 72 patients with rectal carcinoma via transrectal infusion and intravenous injection. The accordance of preoperative dual contrast-enhanced ultrasound results and postoperative pathologic results was evaluated retrospectively. Results: The overall accordance rate of preoperative T staging was 73.6% (53/72). And accordance rate was 100.0% (3/3), 100.0% (5/5), 68.4% (13/19), 71.4% (25/35)and 70.0% (7/10) for Tis , T1, T2, T3 and T4, respectively. The consistency was good (κ=0.607, χ(2) =8.363, P<0.01). The accordance rate of middle/lower vs high rectal carcinoma was 68.7% and 85.7%. Conclusion: Dual contrast-enhanced ultrasound can provide reference for preoperative T staging for patients with rectal carcinoma.

[Analysis on causes of death of residents in Beijing, 1965-1974].

OBJECTIVE: To fill up the absence of data on causes of death of urban residents in Beijing during 1965-1974 and provide evidence for the similar study in other areas. METHODS: All possible sources for death data during 1965-1974 were identified through expert consultations and record search. Stratified sampling was conducted to collect the death data of urban residents during this period in Beijing. The mortality rate, death cause constituent and rank of death causes were used in this descriptive analysis. RESULTS: A total of 11 668 records of deaths from 1965 to 1974 were collected from 10 local police stations in urban area of Beijing. The top 10 death causes in the urban residents were heart disease, tumor, cerebrovascular disease, accidental injury, respiratory system disease, digestive system disease, communicable disease and parasitic disease, nervous system disease, urogenital and reproductive system disease, endocrine and nutrition metabolic diseases. The deaths caused by these diseases accounted for 84.19% of the total deaths. Accidental injury accounted for 13.22% of the total deaths, which was significantly higher than that in either 1964 or 1975, two years before and after this period(P<0.01). Suicide accounted for 54.47% of the total accidental injury deaths. For men, accidental injury was the leading death cause, followed by cancer and heart disease; for women, heart disease, cancer and cerebrovascular disease were the top three death causes. CONCLUSION: The major death cause in urban residents changed from infectious diseases to chronic and non-communicable diseases during 1965-1974. A remarkable high proportion of deaths caused by accidental injury was due to the historical background during that period in Beijing, China.

Meta-analysis of the correlation between the TNF-α308G/A polymorphism and polycystic ovary syndrome.

Previous studies have suggested that the tumor necrosis factor alpha (TNF-α) gene 308G/A polymorphism may be associated with polycystic ovary syndrome (PCOS) risk. However, this relationship is controversial. The present meta-analysis aimed to evaluate the correlation between the TNF-α308G/A polymorphism and susceptibility to PCOS. A systematic electronic search of PubMed and Embase databases was conducted using specific inclusion criteria. Summary odds ratios (ORs) and 95% confidence intervals (95%CIs) were calculated, and all statistical analyses were performed using STATA 12.0. The results of our meta-analysis showed no significant association between the TNF-α308G/A polymorphism and PCOS risk (AA vs GG: OR = 0.80, 95%CI = 0.31-2.08; AG vs GG: OR = 1.03, 95%CI = 0.59-1.81; dominant model: OR = 1.02, 95%CI = 0.60-1.71; recessive model: OR = 0.87, 95%CI = 0.35-2.16). Based on the statistical data, our meta-analysis indicates that the TNF-α308G/A sequence variation may be not related to PCOS susceptibility. Further large and well-designed studies are needed to confirm this conclusion.

[A randomized, single-blind, parallel-controlled and multicentre study: compare the efficacy and safety of domestic and imported human recombinant FSH in WHO group â ¡ anovulatory infertility].

OBJECTIVE: To evaluate the efficacy and safety of domestic human recombinant FSH(rhFSH)in women with anovulation of WHO group Ⅱ. METHODS: A randomized, blind, parallel-controlled, non-inferiority and multicenter study was performed. A total of 534 admitted to 13 hospitals from May 2008 to August 2009. There were 531 women with ovulatory disorder was included in the statistical analysis, were randomly divided into test group(domestic rhFSH, n=352)and control group(imported rhFSH, n=179). Percentage of cycle with mature follicle, ovulation rate, clinical pregnancy rate, multiple pregnancy rate, ovarian hyperstimulation syndrome(OHSS)and adverse events were observed. RESULTS: No statistical significant differences(P>0.05)were observed between the two groups in terms of the efficiency on mature follicle[91.8%(323/352)versus 88.8%(159/179)], ovulation rate[91.3%(295/323)verus 90.6%(144/159)], clinical pregnancy rate[19.2%(62/323)verus 18.2%(29/159)], the number of the follicles<14 mm, the level of serum LH and progesterone, the thickness of endometrium on the day of hCG administration. The number of follicle≥18 mm and 14 mm≤follicle<18 mm and the level of serum estradiol on the day of hCG in the test group were significantly higher than those in the control group(P<0.05). The number of days of rhFSH administration in the test group was significantly less than that in the control group[(9.8±2.2)versus(11.4± 0.6)days, P<0.05], the dosage of rhFSH was significantly lower than that in the control group[(879 ± 419)versus(1 043±663)U, P<0.05]. The multiple pregnancy rate in the test group was significantly higher than that in the control group[21%(13/62)versu 10%(3/29), P<0.05]. The incidence of OHSS and adverse events were similar between the two groups(P>0.05), and no other adverse events were observed in test group during treatment. CONCLUSION: Ovarian stimulation with domestic rhFSH is effective, safe and economical in women with anovulation of WHO group Ⅱ.

The effect of immobilization on the native and repaired tendon-to-bone interface.

BACKGROUND: Little is known of the cellular events that occur in native or repaired tendons as a result of immobilization after injury. To examine this issue, we compared (1) native tendons without immobilization, (2) native tendons with immobilization, and (3) surgically repaired tendons with immobilization. METHODS: Eighty-one rats underwent either patellar tendon repair followed by immobilization or immobilization of the native tendon without repair. A custom external fixation device was used for immobilization. The tendon-bone insertion site was evaluated after two and four weeks of immobilization with use of histologic, radiographic, and biomechanical analyses. RESULTS: Immobilization of the native tendon led to a significant decrease in the load to failure (p < 0.01) and stiffness (p < 0.05) compared with the native tendon at both two and four weeks. The repaired/immobilized group had a significantly lower load to failure at two weeks compared with the native/immobilized group (p < 0.05); however, by four weeks, the repaired group was significantly stronger (p < 0.01). Micro-computerized tomography demonstrated no significant differences in bone microstructure at two weeks but demonstrated increased bone mineral density and bone volume fraction in the repaired/immobilized group at four weeks. There was significantly more MMP-13 (matrix metalloproteinase-13) staining in the native/immobilized specimens compared with the native specimens at both time points (p < 0.01). CONCLUSIONS: Immobilization had a significant detrimental effect on the bone-tendon complex. At two weeks there was a significant decrease in the mechanical properties of the native tendon, but the immobilized, native tendon remained significantly stronger than the repaired and immobilized tendon. However, four weeks of immobilization led to a significant loss of strength of the bone-tendon complex in the native tendon, such that it was significantly weaker than the repaired and immobilized tendon. Surgeons who manage patients with immobilization should be aware of the changes at the bone-tendon complex.

Lipopolysaccharide induces paired immunoglobulin-like receptor B (PirB) expression, synaptic alteration, and learning-memory deficit in rats.

Some typical immune proteins are expressed in the nervous system, among which the paired-immunoglobulin-like receptor B (PirB) is a receptor for major histocompatibility complex class I antigen (MHC-I), but may play a physiological role in the brain for neuronal circuitry stability by inhibiting synaptic plasticity. Chronic neuroinflammation is common to many neurodegenerative diseases and is often associated with neuronal/synaptic damage and dysfunction. Here we examined the expression of PirB in the rat brain following intracerebral application of lipopolysaccharide (LPS), which has been shown to induce proinflammatory changes and cognitive deficits in rodents. One month after unilateral intrahippocampal LPS injection (10 µg in 4 µl phosphate-buffered saline, PBS), increased protein levels and immunoreactivity of PirB were detected in the ipsilateral hippocampal formation and cortex of the experimental group relative to vehicle (PBS) control. The increased PirB labeling was localized to astrocytes and neurons. Reduced synaptophysin protein levels and immunoreactivity were also found in the ipsilateral hippocampal formation and cortex in LPS-treated rats relative to controls. Morris water maze tests indicated that hippocampus-dependent spatial learning and memory were impaired in LPS-treated animals. Our findings add new experimental data for an upregulation of immune proteins in neuronal and glial cells in the brain in a model of endotoxin-induced neuroinflammation, synaptic alteration, and cognitive decline. The results suggest that PirB modulation may be involved in the pathological process under neurodegenerative conditions.

Prevalence of myocardial infarction in patients with psoriasis in central China.

OBJECTIVE: To explore whether the prevalence of myocardial infarction (MI) was higher in psoriatics than in patients without psoriasis, and whether major cardiovascular risk factors were associated with psoriasis in central China. METHODS: Data were collected at Medical Records Section of Affiliated Union Hospital, Tongji Hospital, Wuhan Iron and Steel Company General Hospital and No. 1 Hospital of Wuhan between 1999 and 2007. Patients with psoriasis were classified as severe if they ever received a systemic therapy. And patients were classified as having risk factors if they received codes for diabetes, hypertension, hyperlipidemia, or smoking. Controls without psoriasis were randomly selected from the Physical Examination Centre in the Affiliated Union Hospital. Analysis was performed by using conditional logistic regression, and adjustments were made for age and sex. RESULTS: There were 45 MIs (2.96%) within the control population and 97 (6.00%) and 118 (8.01%) MIs within the mild and severe psoriasis groups, respectively. Respective odds ratio (OR) and 95% confidence interval (95% CI) of cardiovascular risk factors in those with mild psoriasis than controls were as follows: obesity (OR, 1.41; 95% CI, 1.08-1.85), diabetes (OR, 1.45; 95% CI, 1.11-1.91), hypertension (OR, 1.39; 95% CI, 1.04-1.85), hyperlipidemia (OR, 1.37; 95% CI, 1.06-1.78) and smoking (OR, 1.35; 95% CI, 1.01-1.80). Patients with severe psoriasis had higher adjusted odds of obesity (OR, 1.51; 95% CI, 1.15-1.98), diabetes (OR, 1.69; 95% CI, 1.32-2.17), hypertension (OR, 1.41; 95% CI, 1.06-1.88), hyperlipidemia (OR, 1.43; 95% CI, 1.11-1.84), and smoking (OR, 1.57; 95% CI, 1.20-2.05) than patients with mild psoriasis and controls. After adjusting for systemic therapies and cardiovascular risk factors (obesity, diabetes, hypertension, hyperlipidemia and smoking) in addition to age and sex, for patients with mild or severe psoriasis, the OR of having an MI was 1.72 (95% CI, 1.29-2.30) and 2.01 (95% CI, 1.45-2.79), respectively. CONCLUSIONS: The prevalence of MI is higher in mild and severe psoriasis than in patients without psoriasis in central China. In addition, MI and major cardiovascular risk factors (e.g. diabetes, hypertension, hyperlipidemia and smoking) are associated with psoriasis in central China.

Cytokine-induced activation of glial cells in the mouse brain is enhanced at an advanced age.

Numerous neurological diseases which include neuroinflammatory components exhibit an age-related prevalence. The aging process is characterized by an increase of inflammatory mediators both systemically and in the brain, which may prime glial cells. However, little information is available on age-related changes in the glial response of the healthy aging brain to an inflammatory challenge. This problem was here examined using a mixture of the proinflammatory cytokines interferon-gamma and tumor necrosis factor-alpha, which was injected intracerebroventricularly in young (2-3.5 months), middle-aged (10-11 months) and aged (18-21 months) mice. Vehicle (phosphate-buffered saline) was used as control. After a survival of 1 or 2 days (all age groups) or 4 days (young and middle-aged animals), immunohistochemically labeled astrocytes and microglia were investigated both qualitatively and quantitatively. In all age groups, astrocytes were markedly activated in periventricular as well as in deeper brain regions 2 days following cytokine treatment, whereas microglia activation was already evident at 24 h. Interestingly, cytokine-induced activation of both astrocytes and microglia was significantly more marked in the brain of aged animals, in which it included numerous ameboid microglia, than of younger age groups. Moderate astrocytic activation was also seen in the hippocampal CA1 field of vehicle-treated aged mice. FluoroJade B histochemistry and the terminal deoxynucleotidyl transferase-mediated UTP nick-end labeling technique, performed at 2 days after cytokine administration, did not reveal ongoing cell death phenomena in young or aged animals. This indicated that glial cell changes were not secondary to neuronal death. Altogether, the findings demonstrate for the first time enhanced activation of glial cells in the old brain, compared with young and middle-aged subjects, in response to cytokine exposure. Interestingly, the results also suggest that such enhancement does not develop gradually since youth, but appears characterized by relatively late onset.

Effect of compressive strain on cell viability in statically loaded articular cartilage.

Physiological loading of articulating joints is necessary for normal cartilage function. However, conditions of excessive overloading or trauma can cause cartilage injury resulting in matrix damage and cell death. The objective of this study was to evaluate chondrocyte viability within mechanically compressed articular cartilage removed from immature and mature bovine knees. Twenty-three mature and 68 immature cartilage specimens were subjected to static uniaxial confined-creep compressions of 0-70% and the extent of cell death was measured using fluorescent microscopic imaging. In both age groups, cell death was always initiated at the articular surface and increased linearly in depth with increasing strain magnitude. However, most of the cell death was localized within the superficial zone (SZ) of the cartilage matrix with the depth never greater than approximately 500 microm or 25% of the thickness of the test specimen. The immature cartilage was found to have a significantly greater (> 2 times) amount (depth) of cell death compared to the mature cartilage, especially at the higher strains. This finding was attributed to the lower compressive modulus of the immature cartilage in the SZ compared to that of the mature cartilage, resulting in a greater local matrix strain and concomitant cell surface membrane strain in this zone when the matrix was compressed. These results provide further insight into the capacity of articular cartilage in different age groups to resist the severity of traumatic injury from compressive loads.

Thermodynamic modeling of a novel air dehumidification system.

A novel air dehumidification system is proposed. The proposed system incorporates a membrane-based total heat exchanger into a mechanical air dehumidification system, where the fresh air flows through the enthalpy exchanger, the evaporator and the condenser subsequently. Thermodynamic model for the performance estimation of the combined system is investigated. Processes of the fresh air and the refrigerant are studied. Two additional specific programs are devised to calculate the psychrometrics and the thermodynamic properties of the refrigerant R134a. Annual energy requirement is 4.15 × 106 kJ per person, or 33% saving from a system without energy saving measures.

Relapses in leprosy patients treated with rifampicin plus dapsone after varying periods of dapsone monotherapy.

Leprosy patients treated formerly with dapsone monotherapy followed by combined therapy with rifampicin plus dapsone were surveyed for relapse and rifampicin resistance. The relapse rate was significantly low for the 482 multibacillary (MB) patients receiving > 12 months combined therapy compared with the 49 MB cases receiving < 12 months of combined therapy. The relapse rate was related to the duration of dapsone monotherapy prior to combined therapy. The difference in relapse rate in 247 paucibacillary (PB) patients following > 12 months combined therapy was also of significance, compared with the 66 PB cases who had received < 12 months combined therapy. Five strains of M. leprae isolated from relapsed patients were sensitive to rifampicin by mouse foot-pad test and all relapsed patients responded favourably to fixed duration MDT regimen for MB cases.

Rapid magnetic reconnection in the Earth's magnetosphere mediated by whistler waves.

Magnetic reconnection has a crucial role in a variety of plasma environments in providing a mechanism for the fast release of stored magnetic energy. During reconnection the plasma forms a 'magnetic nozzle', like the nozzle of a hose, and the rate is controlled by how fast plasma can flow out of the nozzle. But the traditional picture of reconnection has been unable to explain satisfactorily the short timescales associated with the energy release, because the flow is mediated by heavy ions with a slow resultant velocity. Recent theoretical work has suggested that the energy release is instead mediated by electrons in waves called 'whistlers', which move much faster for a given perturbation of the magnetic field because of their smaller mass. Moreover, the whistler velocity and associated plasma velocity both increase as the 'nozzle' becomes narrower. A narrower nozzle therefore no longer reduces the total plasma flow-the outflow is independent of the size of the nozzle. Here we report observations demonstrating that reconnection in the magnetosphere is driven by whistlers, in good agreement with the theoretical predictions.

[Trophic effect of ciliary neurotrophic factor on denervated skeletal muscle].

AIM: The trophic effect of CNTF on skeletal muscle atrophy and dysfunction reduced by denervation was investigated in SD rats. METHODS: SD rats transected sciatic nerve in right side hind limbs were injected CNTF subcutaneously for 20 days. Skeletal muscle wet weights, protein contents, muscle fiber cross-sectional areas, contract properties and degree of hind limb abnormalities were observed in the rats. RESULTS: (1) Administrating of CNTF (0.2 mg/kg) in sciatic nerve transected SD rats attenuated denervation-induced skeletal muscle fiber atrophy evidently, resulted in gastrocnemius in injury side an obvious increase in contract function, prevented the loss of weights and protein in denervated skeletal muscle, and ameliorated abnormalities in sciatic nerve cut limbs remarkably. (2) The myotrophic effect of 0.2 mg/kg CNTF is more effective than 0.05 mg/kg. (3) The sensitivity to CNTF varied in muscles of different type; slow twitch muscle (soleus muscle) reacted to CNTF stronger and quicker than twitch muscle (extensor digitorum longus). CONCLUSION: CNTF significantly attenuates denervation-reduced skeletal muscle atrophy and dysfunction in SD rats, act an evident myotrophic effect on denervated skeletal muscle. And this effect may be exerted in a dosage dependent manner and varies with muscle type.

Thermal modification of collagen.

Shoulder capsular shrinkage has recently been proposed as a therapeutic modality in a select group of patients with instability. Basic science research studying the mechanism of collagen shrinkage and the effect of shrinkage on the tissue's mechanical properties is essential to define the ideal process by which to achieve optimal tissue shrinkage. Tissue shrinkage is a function of both time and temperature. This relationship was studied, and a model was derived to describe the relationship mathematically. Tissue shrinkage rate was extremely sensitive to temperature changes. The purpose of this study, was to shrink collagenous tissue thermally and then to measure the mechanical property changes as a function of tissue shrinkage. Uniaxial tensile testing of normal and heat-shrunken bovine tendon was carried out, and a model was developed to express the relationship between shrinkage and mechanical properties. We found that the mechanical properties decreased with increasing shrinkage, and that the maximal allowable shrinkage before significant material property changes occurred was between 15% to 20%. Ultrastructural analysis with transmission electron microscopy showed denaturation of the collagen fibrillar structure and provided direct support for the observed material changes.