Preparation of polypeptide-metal complexes-coated Hosenkoside A and its inhibitory effect in cervical cancer

We reported the anti-cervical cancer effect of proprietary saponin content from seeds of Impatiens balsamina L., Hosenkoside A. Our study found that Hosenkoside A significantly promotes cell apoptosis and cell cycle arrest after administration, exhibiting anti-tumor effects. Then the transcriptome sequencing results after administration showed that Hosenkoside A had a significant inhibitory effect on Histone deacetylase 3 (HDAC3). After sufficient administration time, the inhibition of HDAC3 expression level leads to a significant decrease in lysine acetylation at histone 3 sites 4 and 9, blocking the activation of Signal transducer and activator of transcription 3 (STAT3) and achieving anti-tumor effects. In addition, we encapsulated Hosenkoside A into polypeptide metal complexes (PMC) to form slow-release spheres. This material breaks down in the tumor environment, not only does it solve the problem of low drug solubility, but it also achieves targeted sustained-release drug delivery. Under the same concentration of stimulation, the PMC complex group showed better anti-tumor effects in both in vitro and in vivo experiments.

Sleep quality and subjective well-being in healthcare students: examining the role of anxiety and depression

Objective

Sleep issues, negative emotions, and health conditions are commonly co-occurring, whereas their associations among healthcare students have yet to be elucidated. This study aimed to examine whether anxiety and depression mediate the relationship between sleep quality and subjective well-being in healthcare students.

Methods

A cross-sectional survey was conducted among Chinese healthcare students (N = 348). A battery of paper-and-pencil questionnaires-the Sleep Quality Questionnaire (SQQ), World Health Organization-Five Well-Being Index (WHO-5), and Patient Health Questionnaire-4 (PHQ-4) were applied. Descriptive analysis with means (standard deviations) and counts (proportions), Spearman correlation analysis between the SQQ, WHO-5, and PHQ-4, and mediation analysis via structural equation models were performed.

Results

Correlation analysis revealed statistically significant associations between sleep quality, anxiety and depression, and well-being among healthcare students. Mediation analysis identified that poor sleep quality produced relatively low levels of self-reported well-being, which were entirely attributable to anxiety and depression.

Conclusion

Sleep quality was associated with subjective well-being, and this interrelationship was fully mediated by anxiety and depression. Interventions aimed at promoting sleep quality of healthcare students may contribute to promoting their well-being by reducing anxiety and depression.

Association between triglyceride-glucose index and in-hospital mortality in critically ill patients with sepsis: analysis of the MIMIC-IV database

BACKGROUND

This study aimed to explore the association between the triglyceride-glucose (TyG) index and the risk of in-hospital mortality in critically ill patients with sepsis.

METHODS

This was a retrospective observational cohort study and data were obtained from the Medical Information Mart for Intensive Care-IV (MIMIC IV2.2) database. The participants were grouped into three groups according to the TyG index tertiles. The primary outcome was in-hospital all-cause mortality. Multivariable logistics proportional regression analysis and restricted cubic spline regression was used to evaluate the association between the TyG index and in-hospital mortality in patients with sepsis. In sensitivity analysis, the feature importance of the TyG index was initially determined using machine learning algorithms and subgroup analysis based on different subgroups was also performed.

RESULTS

1,257 patients (56.88% men) were included in the study. The in-hospital, 28-day and intensive care unit (ICU) mortality were 21.40%, 26.17%, and 15.43% respectively. Multivariate logistics regression analysis showed that the TyG index was independently associated with an elevated risk of in-hospital mortality (OR 1.440 [95% CI 1.106-1.875]; P = 0.00673), 28-day mortality (OR 1.391; [95% CI 1.52-1.678]; P = 0.01414) and ICU mortality (OR 1.597; [95% CI 1.188-2.147]; P = 0.00266). The restricted cubic spline regression model revealed that the risks of in-hospital, 28-day, and ICU mortality increased linearly with increasing TyG index. Sensitivity analysis indicate that the effect size and direction in different subgroups are consistent, the results is stability. Additionally, the machine learning results suggest that TyG index is an important feature for the outcomes of sepsis.

CONCLUSION

Our study indicates that a high TyG index is associated with an increased in-hospital mortality in critically ill sepsis patients. Larger prospective studies are required to confirm these findings.

Causal effects of genetically vitamins and sepsis risk: a two-sample Mendelian randomization study

BACKGROUND

In recent years, observational studies have been conducted to investigate the potential impact of vitamins on sepsis. However, many of these studies have produced inconsistent results. Our Mendelian randomization (MR) study aims to evaluate the causality between vitamins and sepsis from a genetic perspective.

METHODS

Our MR study was designed following the STROBE-MR guidelines. Genetic instrumental variables for vitamins including folate, vitamin B12, B6, A (Retinol), C, D, and K were obtained from previous genome-wide association studies (GWAS) and MR studies. Five different sepsis severity levels were included in the analysis. The genetic instrumental variables were screened for potential confounders using PhenoScanner V2. MR analysis was performed using MR-egger, inverse-variance weighted multiplicative random effects (IVW-RE), inverse-variance weighted multiplicative fixed-effects (IVW-FE), and wald ratio methods to assess the relationship between vitamins and sepsis. Sensitivity analysis was performed using the MR-egger_intercept method, and the MR-PRESSO package and Cochran's Q test were used to evaluate the heterogeneity of the instrumental variables.

RESULTS

Our MR study found no statistically significant association between vitamins and sepsis risk, regardless of the type of vitamin (P-value > 0.05). The odds ratios (ORs) for folate, vitamin B6, vitamin B12, vitamin A, vitamin D, vitamin K, and vitamin C were 1.164 (95% CI: 0.895-1.514), 0.987 (95% CI: 0.969-1.005), 0.975 (95% CI: 0.914-1.041), 0.993 (95% CI: 0.797-1.238), 0.861 (95% CI: 0.522-1.42), 0.955 (95% CI: 0.86-1.059), and 1.049 (95% CI: 0.911-1.208), respectively. Similar results were observed in subgroups of different sepsis severity levels.

CONCLUSIONS

Our MR study found no evidence of a causal association between vitamins and sepsis risk from a genetic perspective. Further randomized controlled trials are necessary to confirm these results.

Genetic association of lipids and lipid-lowering drugs with sepsis: a Mendelian randomization and mediation analysis

Background

The impact of lipid-lowering medications on sepsis is still not well defined. A Mendelian randomization (MR) study was carried out to probe the causal connections between genetically determined lipids, lipid-reducing drugs, and the risk of sepsis.

Materials and methods

Data on total serum cholesterol (TC), high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol (LDL-C), apolipoprotein A-I (ApoA-I), apolipoprotein B (ApoB), and triglycerides (TG) were retrieved from the MR-Base platform and the Global Lipids Genetics Consortium in 2021 (GLGC2021). Our study categorized sepsis into two groups: total sepsis and 28-day mortality of sepsis patients (sepsis28). The inverse-variance weighted (IVW) method was the primary method used in MR analysis. Cochran's Q test and the MR-Egger intercept method were used to assess the heterogeneity and pleiotropy.

Results

In the MR analysis, we found that ApoA-I played a suggestively positive role in protecting against both total sepsis (OR, 0.863 per SD increase in ApoA-I; 95% CI, 0.780-0.955; P = 0.004) and sepsis28 (OR, 0.759; 95% CI, 0.598-0.963; P = 0.023). HDL-C levels were also found to suggestively reduce the incidence of total sepsis (OR, 0.891 per SD increase in HDL-C; 95% CI, 0.802-0.990; P = 0.031). Reverse-MR showed that sepsis28 led to a decrease in HDL-C level and an increase in TG level. In drug-target MR, we found that HMGCR inhibitors positively protected against total sepsis (1 OR , 0.719 per SD reduction in LDL-C; 95% CI, 0.540-0.958; P = 0.024). LDL-C and HDL-C proxied CETP inhibitors were found to have a protective effect on total sepsis, with only LDL-C proxied CETP inhibitors showing a suggestively protective effect on sepsis28. In Mediated-MR, BMI exhibited a negative indirect effect in HMGCR inhibitors curing sepsis. The indirect impact of ApoA-I explained over 50% of the curative effects of CETP inhibitors in sepsis.

Conclusions

Our MR study suggested that ApoA-I and HDL-C protected against sepsis, while HMGCR and CETP inhibitors showed therapeutic potential beyond lipid-lowering effects. ApoA-I explained the effects of CETP inhibitors. Our study illuminates how lipids affect sepsis patients and the effectiveness of new drugs, opening new avenues for sepsis treatment.

Trick or Drink: Offline and Social Media Hierarchical Normative Influences on Halloween Celebration Drinking

The current study examined the relationship between perceived societal and personal celebration drinking norms, social media use, and alcohol consumption during Halloween. The study used a survey of a nationally representative, convenience, and cross-sectional sample of underage youth (18-20 years old; N = 525). Participants self-reported their own drinking, perceived descriptive norms among peers and close friends, and alcohol-related social media posting and interaction during Halloween. Results revealed that underage youth's estimation of societal drinking norms related to their proximal close friends' drinking norms, which in turn, influenced self-reported number of drinks consumed during Halloween. Social media posting and interaction with alcohol-related content were associated with greater descriptive normative perceptions and self-reported drinking. Extending the hierarchical social norms approach, our findings showed that normative perceptions about proximal reference groups' drinking, along with alcohol-related social media activities, were associated with greater number of drinks consumed during Halloween.

Fancying the New Rich and Famous? Explicating the Roles of Influencer Content, Credibility, and Parental Mediation in Adolescents' Parasocial Relationship, Materialism, and Purchase Intentions

While social media influencers are gleaning increasing trust and investment from brands, advertisers, and followers, insights on the role of influencers in adolescents’ relationship formation and consumption behaviors are still rare. Drawing on the literatures of influencer content value, influencer credibility, parental mediation, and parasocial relationship (PSR), this study proposed a conceptual model that expounds the appeal of influencers among adolescents. To test the model, we administered an online survey – recruited in proportion to demographic quotas (i.e., age, gender and ethnicity) – among 500 United States adolescents (aged 10- to 19-years old) via Qualtrics panel. Results revealed that, the entertainment value of influencer-generated content, influencer expertise, trustworthiness, attractiveness, and followers’ perceived similarity to their favorite influencers, are positively related to the perceived PSR between adolescent followers and their favorite influencers, which in turn, are associated with adolescents’ materialistic views and purchase intentions. We also explored the role of parental mediation of adolescents’ social media use in their PSR with influencers. Results indicate that, neither active mediation nor restrictive mediation is related to the PSR between adolescents and influencers. Active mediation is negatively associated with adolescents’ materialism, whereas restrictive mediation is positively related to adolescents’ purchase intentions toward influencer-promoted products. This study proposed and tested a comprehensive conceptual model that accounts for the role of influencers in adolescent followers’ materialism and purchase intentions. This study yields three major theoretical contributions. First, it adopts and applies the concept of PSR from the literature of media psychology to explicate influencers’ appeal among adolescents, which lays a theoretical foundation for future research on the impact of influencers. Second, it advances the current literature on social media influencers by specifying key contributing factors for the development of adolescents’ PSR with influencers. Lastly, it explores the roles of the two facets of parental mediation – active and restrictive mediation – in the appeal of influencers among adolescents, which offers directions for future research of parental mediation in the influencer context.

Oromandibular reconstruction using microvascularized bone flap: report of 1038 cases from a single institution

This retrospective study was performed to review 1038 patients who underwent mandibular reconstruction with free vascularized bone flaps at a single institution between 2006 and 2017. Of these patients, 827 (79.67%) had fibula flaps, 197 (18.98%) had deep circumflex iliac artery perforator (DCIA) flaps, and 11 (1.06%) had scapula bone flaps. The most common pathological diagnosis was ameloblastoma (n=366, 35.26%), followed by squamous cell carcinoma (n=278, 26.78%) and osteoradionecrosis (n=152, 14.64%). Fifty-seven patients (5.49%) had major complications requiring surgical intervention and one patient died of a pulmonary embolism. Venous crisis was the most frequent major complication (n=20, 1.93%), followed by haematoma (n=17, 1.64%) and flap necrosis (n=14, 1.35%). One-stage mandibular reconstruction was preferred whenever possible, as this generally decreases the financial and hospitalization burden. The four-segment method of jaw reconstruction appeared to achieve good aesthetic appearance results in Asian patients and this was not associated with a higher risk of segment ischemia compared with the three-segment method.

MiR-128 regulation of glucose metabolism and cell proliferation in triple-negative breast cancer

BACKGROUND

Triple-negative breast cancer (TNBC) is prone to metastasis and has a poor prognosis, with lower survival rates than other breast cancer subtypes. MicroRNAs have recently emerged as powerful regulators of cancer processes and become a promising target in cancer therapy.

METHODS

Expression of miR-128 was examined in invasive ductal breast cancer, and its relationship with clinicopathological features analysed. A series of in vitro and in vivo experiments were performed to investigate the function and mechanism of miR-128 in the development of invasive ductal breast cancer.

RESULTS

A cohort of 110 women with TNBC and 117 with non-TNBC were included in the study. In multivariable Cox regression analysis, overall and disease-free survival were significantly associated with lymph node metastasis, histological grade and molecular subtype. Subgroup analysis showed that low expression of miR-128 correlated with shorter overall and disease-free survival in TNBC (P < 0·001), and shorter overall but not disease-free survival in non-TNBC. In addition, miR-128 was able to inhibit glucose metabolism, mitochondrial respiration and proliferation of TNBC cells. These effects were consistent with miR-128 targeting inhibition of the insulin receptor and insulin receptor substrate 1.

CONCLUSION

MiR-128 might be a prognostic marker and possible molecular target for therapy in patients with TNBC.

Clinical efficacy of one stage posterior debridement joint graft fixation for lumbar vertebral fractures in spinal tuberculosis patients with compression

OBJECTIVE

Spinal tuberculosis, though destructive, can be cured in many patients by chemotherapy, though surgery is often necessary for decompression and deformity correction. Our aim of this study was to investigate the clinical efficacy of posterior debridement joint graft fixation therapy for lumbar vertebral fractures in patients with spinal tuberculosis with a compression fracture.

PATIENTS AND METHODS

We prospectively included 48 patients diagnosed with spinal tuberculosis and lumbar compression fracture in our hospital from June 2010 to June 2013. The patients were randomly divided into observation group (n = 27) and control group (n = 21). The patients in the control group underwent an anterior debridement joint bone fixation therapy, whereas, the patients in the observation group underwent one stage posterior debridement joint bone fixation therapy. The patients in the both groups were followed-up for about 2 years and the postoperative complications were recorded and analyzed.

RESULTS

Incision length, operative time and blood loss in patients of the observation group were significantly lower than the control group (p < 0.05). The kyphosis Cobb's angle was found to be reduced in a time-dependent manner in both groups, however, patients in the observation group achieved a significant reduction than the control (p < 0.05). The ASIA grade of few patients in the observation group significantly (p < 0.05) improved to class E from D at the time of the end of follow-up. The patients under the class 'excellent' and 'good' of Kirkaldy-Willis criteria were significantly (p < 05) higher in the observation group (92.6%) than the control group (85.7%). Also, the patients in the Bridwell grade I and II in the observation group (88.9%) were significantly (p < 0.05) higher in comparison with control group (81%). The prevalence of postoperative complications was significantly lower in the observation group (18.5%) when compared with the control group (28.6%).

CONCLUSIONS

Our results indicate that one-stage posterior debridement joint bone fixation therapy is an effective and safe procedure for patients with spinal tuberculosis and lumbar compression; this method is worthy of clinical application.

MiR-485-3p and miR-485-5p suppress breast cancer cell metastasis by inhibiting PGC-1α expression

Breast cancer is the worldwide leading cause of cancer mortality in women. The majority of deaths from breast cancer arise from metastasis of local tumors. Cancer cells support their rapid proliferation by diverting metabolites into anabolic pathways, but during cancer metastasis, the proliferative program of invasive cancer cells is suspended for a migratory phenotype. In this study, we demonstrated that both mature forms of miRNA-485, miR-485-3p and miR-485-5p were involved in regulating mitochondrial respiration, cell migration and cell invasion in breast cancer cells by directly targeting and inhibiting the expression of PGC-1α. Specifically, the expression levels of both miR-485-3p and miR-485-5p were decreased in breast cancer tissues. Overexpression of miR-485-3p and miR-485-5p suppressed mitochondrial respiration and potential for cell migration and invasion in vitro, and also inhibited spontaneous metastasis of breast cancer cells in vivo. The suppression of mitochondrial respiration and cell invasion could be partially relieved by restoration of PGC-1α expression.

Isolation and characterization of OsMY1, a putative partner of OsRac5 from Oryza sativa L

OsRac5 belongs to the rice Rho of plants family, and acts as the molecular switch in the signal pathway which is pivotally involved in the rice fertility control. One of its putative partners, OsMY1, was isolated by yeast two-hybrid screening from rice panicle cDNA library. Bioinformatics analysis shows that OsMY1 contains a coiled-coil domain which generally appeared in the partners of Rho GTPases. By yeast two-hybrid assay, it is confirmed that OsMY1 binds both the wild type (WT) and constitutively active (CA) OsRac5, but does not interact with dominantly negative OsRac5. In addition, the interactions between OsMY1 and WT-OsRac5 or CA-OsRac5 in vivo are demonstrated by bimolecular fluorescence complementation assay. Using PCR-mediated sequence deletion and point mutation of OsMY1, the interaction between OsMY1 and OsRac5 was identified to be mediated by the coiled-coil domain in OsMY1, and their binding was quantified by O-nitro-phenyl-β-D-galactopyranoside assay. Real-time PCR shows that OsMY1 and OsRac5 are coordinately expressed in rice leaves and panicles with similar expression patterns. Our results suggest that OsMY1 is an important target of OsRac5 and that these two genes are involved in the same biological processes in rice growth and development.

Tillering and panicle branching genes in rice

Rice (Oryza sativa L.) is one of the most important staple food crops in the world, and rice tillering and panicle branching are important traits determining grain yield. Since the gene MONOCULM 1 (MOC 1) was first characterized as a key regulator in controlling rice tillering and branching, great progress has been achieved in identifying important genes associated with grain yield, elucidating the genetic basis of yield-related traits. Some of these important genes were shown to be applicable for molecular breeding of high-yielding rice. This review focuses on recent advances, with emphasis on rice tillering and panicle branching genes, and their regulatory networks.

Combining transfer of TTF-1 and Pax-8 gene: a potential strategy to promote radioiodine therapy of thyroid carcinoma

Cotransfer of thyroid-specific transcription factor (TTF)-1 and Pax-8 gene to tumor cells, resulting in the re-expression of iodide metabolism-associated proteins, such as sodium iodide symporter (NIS), thyroglobulin (Tg), thyroperoxidase (TPO), offers the possibility of radioiodine therapy to non-iodide-concentrating tumor because the expression of iodide metabolism-associated proteins in thyroid are mediated by the thyroid transcription factor TTF-1 and Pax-8. The human TTF-1 and Pax-8 gene were transducted into the human thyroid carcinoma (K1 and F133) cells by the recombinant adenovirus, AdTTF-1 and AdPax-8. Re-expression of NIS mRNA and protein, but not TPO and Tg mRNA and protein, was detected in AdTTF-1-infected F133 cells, following with increasing radioiodine uptake (6.1-7.4 times), scarcely iodide organification and rapid iodide efflux (t(1/2) ≈ 8-min in vitro, t(1/2) ≈ 4.7-h in vivo). On contrast, all of the re-expression of NIS, TPO and Tg mRNA and proteins were detected in F133 cells coinfected with AdTTF-1 and AdPax-8. AdTTF-1- and AdPax-8-coinfected K1 and F133 cells could effectively accumulate radioiodine (6.6-7.5 times) and obviously retarded radioiodine retention (t(1/2) ≈ 25-30-min in vitro, t(1/2) ≈ 12-h in vivo) (P<0.05). Accordingly, the effect of radioiodine therapy of TTF-1 and Pax-8 cotransducted K1 and F133 cells (21-25% survival rate in vitro) was better than that of TTF-1-transducted cells (40% survival rate in vitro) (P<0.05). These results indicate that single TTF-1 gene transfer may have limited efficacy of radioiodine therapy because of rapid radioiodine efflux. The cotransduction of TTF-1 and Pax-8 gene, with resulting NIS-mediated radioiodine accumulation and TPO and Tg-mediated radioiodine organification and intracellular retention, may lead to effective radioiodine therapy of thyroid carcinoma.

Different criteria for radioactive sentinel lymph nodes has different impact on sentinel node biopsy in breast cancer patients

BACKGROUND AND OBJECTIVES

This study set out to determine the impact of different criteria for radioactive sentinel lymph nodes (SLNs) on sentinel lymph node biopsy (SLNB), and the optimal criteria for radioactive SLNs.

METHODS

Eighty-four breast cancer patients with cT1-2N0M0 were studied prospectively. Filtered technetium 99 m sulfur colloid was injected in peritumor parenchyma. Three different definitions of SLNs were adopted in each patient: (1) the lymph node with the highest radioactivity. (2) Any lymph node with an in vivo hot spot-to-background activity ratio of at least 3:1 or an ex vivo SLN-to-non-SLN ratio of at least 10:1. (3) All radioactive hot nodes.

RESULTS

With three different definitions, the success rate of sentinel node biopsy were all 96.4%, the sensitivity was 78.9%, 92.1%, 97.4% respectively; false negative rate 21.1%, 7.9%, 2.6% respectively; predicting accuracy 90.1%, 96.3%, 98.8% respectively (P < 0.05). The first, the first two, the first three, and the first four highest radioactive sentinel nodes identified 81.1%, 89.2%, 94.6%, 100% of the positive-SLN patients, respectively.

CONCLUSIONS

The different criteria for radioactive SLNs had different impact on the accuracy, sensitivity, and false negative rate, but not on the success rate, during sentinel node biopsy using radioactive sulfur colloid in breast cancer patients. The first four highest radioactive sentinel nodes could accurately predict the status of axillary metastases. J. Surg. Oncol. 2007;95:635-639. (c) 2007 Wiley-Liss, Inc.

[Vitrification of mouse blastocysts using two kinds of straw systems]

OBJECTIVE

To compare open pulled straws with conventional sorans system for the purpose of establishing an effective vitrification method for mouse blastocysts.

METHODS

With open pulled straws (OPS) and conventional straws, vitrifi- cation of mouse blastocysts was performed, and the survival and hatching rates of the blastocysts were observed after thawing.

RESULTS

After vitrification, the embryo survival in the OPS group (82.3%) was significantly higher than conventional straw group (68.6%, P<0.01), and the hatching rate was also higher (70.3%, P<5

CONCLUSIONS

Vitrification of mouse blastocysts using OPS results in higher survival and hatching rates as compared with conventional straw method.

[Internal strontium-89 radiotherapy for malignant bony metastasis]

OBJECTIVE

This work was done to evaluate the indication, effectiveness, and side effects of internal radiotherapy with radioactive nuclide strontium-89 (89Sr) in patients with malignant metastasis in the bone.

METHODS

Fifty-six patients with skeletal metastasis received this internal radiotherapy. The patients were observed and followed up with respect to pain control, lesion improvement and side effects.

RESULTS

The overall effective rate of pain control was 76.8% with the effective rate of prostatic cancer and breast cancer higher than 80%. The lesions in 81.8% patients as assessed by SPECT imaging, were improved. The mild lowering of white cells, platelets and red cells was the main side effect.

CONCLUSION

Internal radiotherapy with 89Sr is very useful for patients with malignant cancer metastasis in the bone.

Sexual behaviour and contraceptive use among unmarried, young women migrant workers in five cities in China

This paper reports the results of exploratory research on reproductive and sexual health knowledge and sexual behaviour of young, unmarried women who migrate to cities from rural areas for work, and their access to and needs in relation to family planning in Beijing, Guangzhou, Shanghai, Guiyang and Taiyuan, in China. Focus group discussions were conducted with 146 young women aged 16-25 and 58 in-depth interviews with key informants. Some of the young female migrant workers were sexually active and living with their boyfriends, most of whom expected to marry each other. Most of the women lacked basic information about reproduction and contraception, and did not know where or how to obtain contraception. There were social, psychological and economic barriers to accessing services. Only a small proportion of those who were unmarried were using contraception, so induced abortion was often the outcome of unprotected premarital sex. Pleasing male partners also played an important role in unprotected sex. The training, attitudes and approach of the entire family planning service system in relation to unmarried and young people in China, including this migrant population, needs to be reorientated so as to provide them with appropriate and adequate services.

The mechanism of the effect of obesity in knee osteoarthritis: the mediating role of malalignment

OBJECTIVE

Obesity is most strongly linked to osteoarthritis (OA) at the knee. Varus malalignment was examined as a possible local mediator that may increase the impact of body weight at the knee, versus the hip or ankle. Compartment load distribution is more equitable in valgus than in varus knees, and valgus knees may better tolerate obesity. We therefore tested whether 1) body mass index (BMI) is correlated with OA severity in varus knees, 2) the BMI-OA severity correlation is weaker in valgus than in varus knees, 3) BMI is correlated with the severity of varus malalignment, and 4) the BMI-medial tibiofemoral OA severity relationship is reduced after controlling for varus malalignment.

METHODS

In 300 community-recruited patients with knee OA, 2 groups (varus and valgus) were identified based on dominant knee alignment on a full-limb radiograph, i.e., the angle formed by the intersection of the femoral and tibial mechanical axes. Severity of knee OA was assessed by measurement of the narrowest joint space width on radiographs of knees in a fluoroscopy-confirmed semiflexed position.

RESULTS

Alignment direction was symmetric (or neutral in 1 limb) in 87% of patients. One hundred fifty-four patients had varus knees and 115 had valgus knees. BMI correlated with OA severity in the varus group (r = -0.29, P = 0.0009) but not in the valgus group (r = -0.13, P = 0.17). BMI correlated with malalignment in those with varus knees (r = 0.26) but not in those with valgus knees (r = 0.16). The partial correlation of BMI and OA severity, controlling for sex, was reduced from 0.24 (P = 0.002) to 0.04 (P = 0.42) when varus malalignment was added to the model.

CONCLUSION

BMI was related to OA severity in those with varus knees but not in those with valgus knees. Much of the effect of BMI on the severity of medial tibiofemoral OA was explained by varus malalignment, after controlling for sex. Whether it precedes or follows the onset of disease, varus malalignment is one local factor that may contribute to rendering the knee most vulnerable to the effects of obesity.

The effect of gestational parity on FEV1 in a group of healthy volunteer women

In the past, studies utilizing within-subject comparisons of small groups of pregnant women showed that forced expiratory volume in 1 s (FEV1) remained essentially unchanged during pregnancy. However, one of the findings from an epidemiological study was that women with greater number of children experienced a faster decline of FEV1. The aim of this study was to examine the effect of parity on FEV1 in a group of healthy volunteer women. To this end, cross-sectional multiple regression analyses of data from 397 healthy women participants in the Baltimore Longitudinal Study of Aging (BLSA) with a mean (range) age of 47.7 (18-92) years were performed. Similar analyses were done using the younger (50 years or less) and the older (> 50 years) subgroups. After controlling for age, height, weight, and smoking, parity as a dichotomous variable was associated with a higher FEV1 in women of child-bearing age (0.139 1; P = 0.02) but not in the older women. There was a modest link with the number of children (P = 0.05), with the first child possibly having the greatest effect on FEV1. We could not account for the effect of parity on FEV1 by the educational level, occupation, health status of the women, or by the presence of a cohort effect. Thus the nulliparous state is associated with lower FEV1 in this group of healthy adult women of child-bearing age.

Laxity in healthy and osteoarthritic knees

OBJECTIVE

Although it is a cause of osteoarthritis (OA) in animal models, laxity in human knee OA has been minimally evaluated. Ligaments become more compliant with age; whether this results in clinical laxity is not clear. In theory, laxity may predispose to OA and/or result from OA. Our goals were to examine the correlation of age and sex with knee laxity in control subjects without OA, compare laxity in uninvolved knees of OA patients with that in older control knees, and examine the relationship between specific features of OA and knee laxity.

METHODS

We assessed varus-valgus and anteroposterior laxity in 25 young control subjects, 24 older control subjects without clinical OA, radiographic OA, or a history of knee injury, and 164 patients with knee OA as determined by the presence of definite osteophytes. A device was designed to assess varus-valgus laxity under a constant varus or valgus load while maintaining a fixed knee flexion angle and thigh and ankle immobilization. Radiographic evaluations utilized protocols addressing position, beam alignment, magnification, and landmark definition; the semiflexed position was used, with fluoroscopic confirmation.

RESULTS

In the controls, women had greater varus-valgus laxity than did men (3.6 degrees versus 2.7 degrees; 95% confidence interval [95% CI] of difference 0.38, 1.56; P = 0.004), and laxity correlated modestly with age (r = 0.29, P = 0.04). Varus-valgus laxity was greater in the uninvolved knees of OA patients than in older control knees (4.9 degrees versus 3.4 degrees; 95% CI of difference 0.60, 2.24; P = 0.0006). In OA patients, varus-valgus laxity increased as joint space decreased (slope -0.34; 95% CI -0.48, -0.19; P < 0.0001) and was greater in knees with than in knees without bony attrition (5.3 degrees versus 4.5 degrees; 95% CI of difference 0.32, 1.27; P = 0.001).

CONCLUSION

Greater varus-valgus laxity in the uninvolved knees of OA patients versus older control knees and an age-related increase in varus-valgus laxity support the concept that some portion of the increased laxity of OA may predate disease. Loss of cartilage/bone height is associated with greater varus-valgus laxity. These results raise the possibility that varus-valgus laxity may increase the risk of knee OA and cyclically contribute to progression.

Does laxity alter the relationship between strength and physical function in knee osteoarthritis?

OBJECTIVE

Since strengthening interventions have had a lower-than-expected impact on patient function in studies of knee osteoarthritis (OA) and it is known that laxity influences muscle activity, this study examined whether the relationship between strength and function is weaker in the presence of laxity.

METHODS

One hundred sixty-four patients with knee OA were studied. Knee OA was defined by the presence of definite osteophytes, and patients had to have at least a little difficulty with knee-requiring activities. Tests were performed to determine quadriceps and hamstring strength, varus-valgus laxity, functional status (Western Ontario and McMaster Universities Osteoarthritis Index Physical Functioning subscale [WOMAC-PF] and chair-stand performance), body mass index, and pain. High and low laxity groups were defined as above and below the sample median, respectively.

RESULTS

Strength and chair-stand rates correlated (r = 0.44 to 0.52), as did strength and the WOMAC-PF score (r = -0.21 to -0.36). In multivariate analyses, greater laxity was consistently associated with a weaker relationship between strength (quadriceps or hamstring) and physical functioning (chair-stand rate or WOMAC-PF score).

CONCLUSION

Varus-valgus laxity is associated with a decrease in the magnitude of the relationship between strength and physical function in knee OA. In studies examining the functional and structural consequences of resistance exercise in knee OA, stratification of analyses by varus-valgus laxity should be considered. The effect of strengthening interventions in knee OA may be enhanced by consideration of the status of the passive restraint system.

Non-inherited maternal HLA antigens and protection against sensitisation

To test the hypothesis that non-inherited maternal antigens (NIMAs), which reportedly afford protection against sensitisation by random transfusions, can provide protection against repetitive antigenic exposure of donor-specific transfusion (DST), 140 DST patients whose donors were mismatched for NIMAs and 71 whose donors were mismatched for non-inherited paternal antigens (NIPAs) were studied. The rate of sensitisation in the two groups of patients was similar (22.1% vs 15.5%). There was no difference in sensitisation to NIMAs and NIPAs between patients who received azathioprine and those who did not. The formation of donor specific HLA antibody was comparable in the two groups. After kidney transplantation there were no differences in 1-year graft survival or the incidence of rejection episodes. These findings suggest that NIMAs do not provide lifelong protection against subsequent repetitive antigen challenge and sensitisation.