Analysis of free cisplatin in microdialysates and plasma ultrafiltrate by liquid chromatography-tandem mass spectrometry

Cisplatin is a potent cytotoxic agent used in the treatment of various malignancies and exerts its antitumor effect through malignant cell DNA damage and apoptosis induction. Evaluation of systemic delivery of cisplatin is important in optimization of cisplatin treatment. However, accurate quantification of systemic cisplatin is challenging due to its various forms in circulation. This study aimed to develop a sensitive (LOQ < 0.1 µg/mL) and precise Ultra Performance Liquid Chromatography (UPLC) - Tandem Mass Spectrometry (MS/MS) method for quantifying free cisplatin in microdialysates and plasma. Furthermore the aim was to compare free cisplatin concentrations measured in standard plasma samples with those obtained from intravenous microdialysis catheters in a porcine model. The method developed utilizes dichloro(ethylenediamine)platinum(II) as an internal standard that co-elutes with cisplatin, ensuring precise correction for ion suppression/enhancement effects. The method was validated, demonstrating linearity up to 100 µg/mL and good intermediate precision (CV% < 6 %) in the range of 1.0-100 µg/mL, with an LOQ of 0.03 µg/mL. The pharmacokinetic parameters (AUC0-last, Cmax, T1/2, and Tmax) showed no significant differences between the two sampling methods. This validated LC-MS/MS method provides a reliable tool for quantifying systemic free cisplatin concentrations, facilitating future systemic and local pharmacokinetic evaluations for optimization of cisplatin-based cancer treatments.

Low attendance by non-native women to human papillomavirus vaccination and cervical cancer screening - A Danish nationwide register-based cohort study

Background

Cervical cancer is preventable through human papillomavirus vaccination and cervical cancer screening. However, possibly due to systemic, individual (e.g. low socio-economic staus) and socio-cultural barriers, it is likely that non-natives, especially non-westerns, are more prone to attend neither vaccination nor screening (combined non-attendance). This is disturbing as the non-native population in Denmark is predicted to rise to 21% by 2060. We aimed to investigate differences in combined non-attendance by nativity and region of origin, and to analyse the association between country of origin and combined non-attendance adjusted for socio-economic status.

Setting

1.6.2007–31.12.2016 Denmark.

Methods

Logistic regression was performed to estimate crude and adjusted odds ratios with 95% confidence intervals for combined non-attendance.

Results

170,158 women were included. Overall combined non-attendance was 11.8% [11.7–12.0]; 10.0% [9.8–10.1] for native women and 27.1% [26.4–27.7] for non-native women, with highest degrees among Middle-Eastern and North-Africans (30.1% [29.2–30.9]). Even when adjusted for socio-economics, women from Middle-East and North-Africa had substantially higher odds of combined non-attendance than natives (adj. OR = 7.5 [6.3–8.9] for Somali women).

Conclusion

Denmark has a relatively low degree of combined non-attendance. However, cervical cancer preventive programmes seem to be better tailored to the needs of native women and do not appear to cater sufficiently to the needs of the fast-growing non-native populations, particularly not to the needs of Middle-Eastern and North African women. In order to secure more just cervical cancer prevention, future studies are recommended to develop tailored intervention sensitive to the need of non-native women.

Validity and reliability of State-Trait Anxiety Inventory in Danish women aged 45 years and older with abnormal cervical screening results

Background

State Trait Anxiety Inventory (STAI) scale was developed in the 1980’s and has been widely used both in clinical settings and in research. However the Danish version of STAI has not been validated. The aim of this study was to assess the validity and reliability of STAI - state anxiety scale in Danish women aged 45 years and older with abnormal cervical cancer screening results.

Methods

Women ≥45 years referred with an abnormal cervical cytology and healthy volunteers (n = 12) underwent cognitive interview after completing STAI. Further, STAI was sent out in an electronic questionnaire to women (n = 109) seen at the gynecological department with abnormal cervical cancer screening test during 2018. Validity and reliability of STAI was evaluated according to the Consensus-based Standards for the selection of health Measurement Instruments (COSMIN) checklist by examining internal consistency, test-retest reliability, measurement error, floor and ceiling, construct validity and content validity.

Results

In the cognitive interviews the content validity was evaluated to be very good. The internal consistency of the scale was excellent with Cronbach’s α = 0.93. Test-retest reliability was good with an intra-class correlation coefficient of 0.80 and the systematic difference between test-retest results was negligible. The construct validity was good.

Conclusion

To our best knowledge, this is the first validation study of the Danish translation of STAI-state anxiety scale. This version of STAI demonstrates an acceptable reliability and validity when used in a gynecological setting.

Athero-inflammatory nanotherapeutics: Ferulic acid-based poly(anhydride-ester) nanoparticles attenuate foam cell formation by regulating macrophage lipogenesis and reactive oxygen species generation

Enhanced bioactive anti-oxidant formulations are critical for treatment of inflammatory diseases, such as atherosclerosis. A hallmark of early atherosclerosis is the uptake of oxidized low density lipoprotein (oxLDL) by macrophages, which results in foam cell and plaque formation in the arterial wall. The hypolipidemic, anti-inflammatory, and antioxidative properties of polyphenol compounds make them attractive targets for treatment of atherosclerosis. However, high concentrations of antioxidants can reverse their anti-atheroprotective properties and cause oxidative stress within the artery. Here, we designed a new class of nanoparticles with anti-oxidant polymer cores and shells comprised of scavenger receptor targeting amphiphilic macromolecules (AMs). Specifically, we designed ferulic acid-based poly(anhydride-ester) nanoparticles to counteract the uptake of high levels of oxLDL and regulate reactive oxygen species generation (ROS) in human monocyte derived macrophages (HMDMs). Compared to all compositions examined, nanoparticles with core ferulic acid-based polymers linked by diglycolic acid (PFAG) showed the greatest inhibition of oxLDL uptake. At high oxLDL concentrations, the ferulic acid diacids and polymer nanoparticles displayed similar oxLDL uptake. Treatment with the PFAG nanoparticles downregulated the expression of macrophage scavenger receptors, CD-36, MSR-1, and LOX-1 by about 20-50%, one of the causal factors for the decrease in oxLDL uptake. The PFAG nanoparticle lowered ROS production by HMDMs, which is important for maintaining macrophage growth and prevention of apoptosis. Based on these results, we propose that ferulic acid-based poly(anhydride ester) nanoparticles may offer an integrative strategy for the localized passivation of the early stages of the atheroinflammatory cascade in cardiovascular disease.

STATEMENT OF SIGNIFICANCE

Future development of anti-oxidant formulations for atherosclerosis applications is essential to deliver an efficacious dose while limiting localized concentrations of pro-oxidants. In this study, we illustrate the potential of degradable ferulic acid-based polymer nanoparticles to control macrophage foam cell formation by significantly reducing oxLDL uptake through downregulation of scavenger receptors, CD-36, MSR-1, and LOX-1. Another critical finding is the ability of the degradable ferulate-based polymer nanoparticles to lower macrophage reactive oxygen species (ROS) levels, a precursor to apoptosis and plaque escalation. The degradable ferulic acid-based polymer nanoparticles hold significant promise as a means to alter the treatment and progression of atherosclerosis.

Lipocalin-2-loaded amphiphilic polyanhydride microparticles accelerate cell migration

This work demonstrates that amphiphilic polyanhydride microparticles based on co-polymers of 1,6-bis(p-carboxyphenoxy)hexane (CPH) and 1,6-bis(p-carboxyphenoxy)-3,6-dioxaoctane (CPTEG) provide stabilizing environments for proteins. A cryogenic atomization method was used to fabricate protein-loaded polyanhydride microparticles. These microparticles were tested for their ability to provide controlled delivery of lipocalin 2 (Lcn2) and to maintain its structure and function. Lcn2 is an acute-phase protein suspected to play a role in cell migration and tissue repair. The in vitro release kinetics of Lcn2 from the microparticles were a function of the chemistry of the polymer carrier. The biological activity of Lcn2 released from polyanhydride microparticles was investigated by its ability to stimulate migration of human colon epithelial cells (HCT116). Lcn2 released from 50:50 and 20:80 CPTEG/CPH microparticles maintained its biological activity as demonstrated by the increased rate of cell migration. In addition, the Lcn2-loaded 50:50 and 20:80 CPTEG/CPH microparticles promoted cell migration over that of the Lcn2 administered alone. This was interpreted as the ability of the amphiphilic microparticles to stabilize the encapsulated protein and release it in a controlled manner over a period of time. This work demonstrates the potential for therapeutic use of amphiphilic polyanhydride microparticles as protein/drug carriers.

Amphiphilic macromolecule nanoassemblies suppress smooth muscle cell proliferation and platelet adhesion

While the development of second- and third-generation drug-eluting stents (DES) have significantly improved patient outcomes by reducing smooth muscle cell (SMC) proliferation, DES have also been associated with an increased risk of late-stent thrombosis due to delayed re-endothelialization and hypersensitivity reactions from the drug-polymer coating. Furthermore, DES anti-proliferative agents do not counteract the upstream oxidative stress that triggers the SMC proliferation cascade. In this study, we investigate biocompatible amphiphilic macromolecules (AMs) that address high oxidative lipoprotein microenvironments by competitively binding oxidized lipid receptors and suppressing SMC proliferation with minimal cytotoxicity. To determine the influence of nanoscale assembly on proliferation, micelles and nanoparticles were fabricated from AM unimers containing a phosphonate or carboxylate end-group, a sugar-based hydrophobic domain, and a hydrophilic poly(ethylene glycol) domain. The results indicate that when SMCs are exposed to high levels of oxidized lipid stimuli, nanotherapeutics inhibit lipid uptake, downregulate scavenger receptor expression, and attenuate scavenger receptor gene transcription in SMCs, and thus significantly suppress proliferation. Although both functional end-groups were similarly efficacious, nanoparticles suppressed oxidized lipid uptake and scavenger receptor expression more effectively compared to micelles, indicating the relative importance of formulation characteristics (e.g., higher localized AM concentrations and nanotherapeutic stability) in scavenger receptor binding as compared to AM end-group functionality. Furthermore, AM coatings significantly prevented platelet adhesion to metal, demonstrating its potential as an anti-platelet therapy to treat thrombosis. Thus, AM micelles and NPs can effectively repress early stage SMC proliferation and thrombosis through non-cytotoxic mechanisms, highlighting the promise of nanomedicine for next-generation cardiovascular therapeutics.

Nanotherapeutics for inhibition of atherogenesis and modulation of inflammation in atherosclerotic plaques

AIMS

Atherosclerotic development is exacerbated by two coupled pathophysiological phenomena in plaque-resident cells: modified lipid trafficking and inflammation. To address this therapeutic challenge, we designed and investigated the efficacy in vitro and ex vivo of a novel 'composite' nanotherapeutic formulation with dual activity, wherein the nanoparticle core comprises the antioxidant α-tocopherol and the shell is based on sugar-derived amphiphilic polymers that exhibit scavenger receptor binding and counteract atherogenesis.

METHODS AND RESULTS

Amphiphilic macromolecules were kinetically fabricated into serum-stable nanoparticles (NPs) using a core/shell configuration. The core of the NPs comprised either of a hydrophobe derived from mucic acid, M12, or the antioxidant α-tocopherol (α-T), while an amphiphile based on PEG-terminated M12 served as the shell. These composite NPs were then tested and validated for inhibition of oxidized lipid accumulation and inflammatory signalling in cultures of primary human macrophages, smooth muscle cells, and endothelial cells. Next, the NPs were evaluated for their athero-inflammatory effects in a novel ex vivo carotid plaque model and showed similar effects within human tissue. Incorporation of α-T into the hydrophobic core of the NPs caused a pronounced reduction in the inflammatory response, while maintaining high levels of anti-atherogenic efficacy.

CONCLUSIONS

Sugar-based amphiphilic macromolecules can be complexed with α-T to establish new anti-athero-inflammatory nanotherapeutics. These dual efficacy NPs effectively inhibited key features of atherosclerosis (modified lipid uptake and the formation of foam cells) while demonstrating reduction in inflammatory markers based on a disease-mimetic model of human atherosclerotic plaques.

Pulmonary biodistribution and cellular uptake of intranasally administered monodisperse particles

PURPOSE

For the rational design of nanovaccines against respiratory pathogens, careful selection of optimal particle size and chemistry is paramount. This work investigates the impact of these properties on the deposition, biodistribution, and cellular interactions of nanoparticles within the lungs.

METHOD

In this work, biodegradable poly(sebacic anhydride) (poly(SA)) nanoparticles of multiple sizes were synthesized with narrow particle size distributions. The lung deposition and retention as well as the internalization by phagocytic cells of these particles were compared to that of non-degradable monodisperse polystyrene nanoparticles of similar sizes.

RESULTS

The initial deposition of intranasally administered particles in the lungs was dependent on primary particle size, with maximal deposition occurring for the 360-470 nm particles, regardless of chemistry. Over time, both particle size and chemistry affected the frequency of particle-positive cells and the specific cell types taking up particles. The biodegradable poly(SA) particles associated more closely with phagocytic cells and the dynamics of this association impacted the clearance of these particles from the lung.

CONCLUSIONS

The findings reported herein indicate that both size and chemistry control the fate of intranasally administered particles and that the dynamics of particle association with phagocytic cells in the lungs provide important insights for the rational design of pulmonary vaccine delivery vehicles.

Amphiphilic nanoparticles repress macrophage atherogenesis: novel core/shell designs for scavenger receptor targeting and down-regulation

Atherosclerosis, an inflammatory lipid-rich plaque disease is perpetuated by the unregulated scavenger-receptor-mediated uptake of oxidized lipoproteins (oxLDL) in macrophages. Current treatments lack the ability to directly inhibit oxLDL accumulation and foam cell conversion within diseased arteries. In this work, we harness nanotechnology to design and fabricate a new class of nanoparticles (NPs) based on hydrophobic mucic acid cores and amphiphilic shells with the ability to inhibit the uncontrolled uptake of modified lipids in human macrophages. Our results indicate that tailored NP core and shell formulations repress oxLDL internalization via dual complementary mechanisms. Specifically, the most atheroprotective molecules in the NP cores competitively reduced NP-mediated uptake to scavenger receptor A (SRA) and also down-regulated the surface expression of SRA and CD36. Thus, nanoparticles can be designed to switch activated, lipid-scavenging macrophages to antiatherogenic phenotypes, which could be the basis for future antiatherosclerotic therapeutics.

Lung deposition and cellular uptake behavior of pathogen-mimicking nanovaccines in the first 48 hours

Pulmonary immunization poses the unique challenge of balancing vaccine efficacy with minimizing inflammation in the respiratory tract. While previous studies have shown that mice immunized intranasally with F1-V-loaded polyanhydride nanoparticles are protected from a lethal challenge with Yersinia pestis, little is known about the initial interaction between the nanoparticles and immune cells following intranasal administration. Here, the deposition within the lung and internalization by phagocytic cells of polyanhydride nanovaccines encapsulating F1-V are compared with that of soluble F1-V alone or F1-V adjuvanted with monophosphoryl lipid A (MPLA). Encapsulation of F1-V into polyanhydride nanoparticles prolonged its presence while F1-V administered with MPLA is undetectable within 48 h. The inflammation induced by the polyanhydride nanovaccine is mild compared with the marked inflammation induced by the MPLA-adjuvanted F1-V. Even though F1-V delivered with saline is detected in the lung 48 h after administration, it is known that this regimen does not elicit a protective immune response. The prolonged F1-V presence in the lung in concert with the mild inflammatory response provided by the nanovaccine provides new insights into the development of protective immune responses with a single intranasal dose.

Can adenocarcinoma in situ of the uterine cervix be treated safely by conisation in combination with endocervical curettage?

OBJECTIVE

To evaluate the prognostic value of endocervical curettage (ECC) after conisation in patients treated for adenocarcinoma in situ (AIS) of the uterine cervix.

MATERIALS AND METHODS

Patients with AIS diagnosed between 1990 and 2010 and with a minimum of 1.5 years of follow-up were retrospectively identified using computerised clinical files.

RESULTS

The authors identified 195 patients (median age 32 years) with a median follow-up of 6.4 years. ECC was performed in 165 patients. In 144 (87%) the initial ECC was normal. In 129 no recurrence was observed during follow-up (90%). A positive ECC was observed in 21. Thirteen patients had hysterectomies; six hysterectomies were normal. Eight patients treated conservatively developed no recurrent disease. Two patients with a positive ECC did not have a hysterectomy and developed recurrent disease. In patients with affected margins, 17% developed recurrent disease.

CONCLUSION

ECC performed during initial conisation is a prognostic tool for the treatment ofAIS. Close follow-up is recommended in patients treated conservatively.

Retention of structure, antigenicity, and biological function of pneumococcal surface protein A (PspA) released from polyanhydride nanoparticles

Pneumococcal surface protein A (PspA) is a choline-binding protein which is a virulence factor found on the surface of all Streptococcus pneumoniae strains. Vaccination with PspA has been shown to be protective against a lethal challenge with S. pneumoniae, making it a promising immunogen for use in vaccines. Herein the design of a PspA-based subunit vaccine using polyanhydride nanoparticles as a delivery platform is described. Nanoparticles based on sebacic acid (SA), 1,6-bis-(p-carboxyphenoxy)hexane (CPH) and 1,8-bis-(p-carboxyphenoxy)-3,6-dioxaoctane (CPTEG), specifically 50:50 CPTEG:CPH and 20:80 CPH:SA, were used to encapsulate and release PspA. The protein released from the nanoparticle formulations retained its primary and secondary structure as well as its antigenicity. The released PspA was also biologically functional based on its ability to bind to apolactoferrin and prevent its bactericidal activity against Escherichia coli. When the PspA nanoparticle formulations were administered subcutaneously to mice they elicited a high titer and high avidity anti-PspA antibody response. Together these studies provide a framework for the rational design of a vaccine against S. pneumoniae based on polyanhydride nanoparticles.

In silico design of anti-atherogenic biomaterials

Atherogenesis, the uncontrolled deposition of modified lipoproteins in inflamed arteries, serves as a focal trigger of cardiovascular disease (CVD). Polymeric biomaterials have been envisioned to counteract atherogenesis based on their ability to repress scavenger mediated uptake of oxidized lipoprotein (oxLDL) in macrophages. Following the conceptualization in our laboratories of a new library of amphiphilic macromolecules (AMs), assembled from sugar backbones, aliphatic chains and poly(ethylene glycol) tails, a more rational approach is necessary to parse the diverse features such as charge, hydrophobicity, sugar composition and stereochemistry. In this study, we advance a computational biomaterials design approach to screen and elucidate anti-atherogenic biomaterials with high efficacy. AMs were quantified in terms of not only 1D (molecular formula) and 2D (molecular connectivity) descriptors, but also new 3D (molecular geometry) descriptors of AMs modeled by coarse-grained molecular dynamics (MD) followed by all-atom MD simulations. Quantitative structure-activity relationship (QSAR) models for anti-atherogenic activity were then constructed by screening a total of 1164 descriptors against the corresponding, experimentally measured potency of AM inhibition of oxLDL uptake in human monocyte-derived macrophages. Five key descriptors were identified to provide a strong linear correlation between the predicted and observed anti-atherogenic activity values, and were then used to correctly forecast the efficacy of three newly designed AMs. Thus, a new ligand-based drug design framework was successfully adapted to computationally screen and design biomaterials with cardiovascular therapeutic properties.

Combinatorial evaluation of in vivo distribution of polyanhydride particle-based platforms for vaccine delivery

Several challenges are associated with current vaccine strategies, including repeated immunizations, poor patient compliance, and limited approved routes for delivery, which may hinder induction of protective immunity. Thus, there is a need for new vaccine adjuvants capable of multi-route administration and prolonged antigen release at the site of administration by providing a depot within tissue. In this work, we designed a combinatorial platform to investigate the in vivo distribution, depot effect, and localized persistence of polyanhydride nanoparticles as a function of nanoparticle chemistry and administration route. Our observations indicated that the route of administration differentially affected tissue residence times. All nanoparticles rapidly dispersed when delivered intranasally but provided a depot when administered parenterally. When amphiphilic and hydrophobic nanoparticles were administered intranasally, they persisted within lung tissue. These results provide insights into the chemistry- and route-dependent distribution and tissue-specific association of polyanhydride nanoparticle-based vaccine adjuvants.

Evaluation of biocompatibility and administration site reactogenicity of polyanhydride-particle-based platform for vaccine delivery

Efficacy, purity, safety, and potency are important attributes of vaccines. Polyanhydride particles represent a novel class of vaccine adjuvants and delivery platforms that have demonstrated the ability to enhance the stability of protein antigens as well as elicit protective immunity against bacterial pathogens. This work aims to elucidate the biocompatibility, inflammatory reactions, and particle effects on mice injected with a 5 mg dose of polyanhydride nanoparticles via common parenteral routes (subcutaneous and intramuscular). Independent of polymer chemistry, nanoparticles more effectively disseminated away from the injection site as compared to microparticles, which exhibited a depot effect. Using fluorescent probes, the in vivo distribution of three formulations of nanoparticles, following subcutaneous administration, indicated migration away from the injection site. Less inflammation was observed at the injection sites of mice-administered nanoparticles as compared to Alum and incomplete Freund's adjuvant. Furthermore, histological evaluation revealed minimal adverse injection site reactions and minimal toxicological effects associated with the administration of nanoparticles at 30 days post-administration. Collectively, these results demonstrate that polyanhydride nanoparticles do not induce inflammation as a cumulative effect of particle persistence or degradation and are, therefore, a viable candidate for a vaccine delivery platform.

Combinatorial Synthesis of and high-throughput protein release from polymer film and nanoparticle libraries

Polyanhydrides are a class of biomaterials with excellent biocompatibility and drug delivery capabilities. While they have been studied extensively with conventional one-sample-at-a-time synthesis techniques, a more recent high-throughput approach has been developed enabling the synthesis and testing of large libraries of polyanhydrides(1). This will facilitate more efficient optimization and design process of these biomaterials for drug and vaccine delivery applications. The method in this work describes the combinatorial synthesis of biodegradable polyanhydride film and nanoparticle libraries and the high-throughput detection of protein release from these libraries. In this robotically operated method (Figure 1), linear actuators and syringe pumps are controlled by LabVIEW, which enables a hands-free automated protocol, eliminating user error. Furthermore, this method enables the rapid fabrication of micro-scale polymer libraries, reducing the batch size while resulting in the creation of multivariant polymer systems. This combinatorial approach to polymer synthesis facilitates the synthesis of up to 15 different polymers in an equivalent amount of time it would take to synthesize one polymer conventionally. In addition, the combinatorial polymer library can be fabricated into blank or protein-loaded geometries including films or nanoparticles upon dissolution of the polymer library in a solvent and precipitation into a non-solvent (for nanoparticles) or by vacuum drying (for films). Upon loading a fluorochrome-conjugated protein into the polymer libraries, protein release kinetics can be assessed at high-throughput using a fluorescence-based detection method (Figures 2 and 3) as described previously(1). This combinatorial platform has been validated with conventional methods(2) and the polyanhydride film and nanoparticle libraries have been characterized with (1)H NMR and FTIR. The libraries have been screened for protein release kinetics, stability and antigenicity; in vitro cellular toxicity, cytokine production, surface marker expression, adhesion, proliferation and differentiation; and in vivo biodistribution and mucoadhesion(1-11). The combinatorial method developed herein enables high-throughput polymer synthesis and fabrication of protein-loaded nanoparticle and film libraries, which can, in turn, be screened in vitro and in vivo for optimization of biomaterial performance.

Amphiphilic polyanhydride nanoparticles stabilize Bacillus anthracis protective antigen

Advancements toward an improved vaccine against Bacillus anthracis, the causative agent of anthrax, have focused on formulations composed of the protective antigen (PA) adsorbed to aluminum hydroxide. However, due to the labile nature of PA, antigen stability is a primary concern for vaccine development. Thus, there is a need for a delivery system capable of preserving the immunogenicity of PA through all the steps of vaccine fabrication, storage, and administration. In this work, we demonstrate that biodegradable amphiphilic polyanhydride nanoparticles, which have previously been shown to provide controlled antigen delivery, antigen stability, immune modulation, and protection in a single dose against a pathogenic challenge, can stabilize and release functional PA. These nanoparticles demonstrated polymer hydrophobicity-dependent preservation of the biological function of PA upon encapsulation, storage (over extended times and elevated temperatures), and release. Specifically, fabrication of amphiphilic polyanhydride nanoparticles composed of 1,6-bis(p-carboxyphenoxy)hexane and 1,8-bis(p-carboxyphenoxy)-3,6-dioxaoctane best preserved PA functionality. These studies demonstrate the versatility and superiority of amphiphilic nanoparticles as vaccine delivery vehicles suitable for long-term storage.

Rational design of pathogen-mimicking amphiphilic materials as nanoadjuvants

An opportunity exists today for cross-cutting research utilizing advances in materials science, immunology, microbial pathogenesis, and computational analysis to effectively design the next generation of adjuvants and vaccines. This study integrates these advances into a bottom-up approach for the molecular design of nanoadjuvants capable of mimicking the immune response induced by a natural infection but without the toxic side effects. Biodegradable amphiphilic polyanhydrides possess the unique ability to mimic pathogens and pathogen associated molecular patterns with respect to persisting within and activating immune cells, respectively. The molecular properties responsible for the pathogen-mimicking abilities of these materials have been identified. The value of using polyanhydride nanovaccines was demonstrated by the induction of long-lived protection against a lethal challenge of Yersinia pestis following a single administration ten months earlier. This approach has the tantalizing potential to catalyze the development of next generation vaccines against diseases caused by emerging and re-emerging pathogens.

Hoping for the best, preparing for the worst: the lived experiences of women undergoing ovarian cancer surgery

In this study, the lived experiences of women undergoing ovarian cancer surgery were explored, aiming to provide a patient perspective on being newly diagnosed and starting treatment for ovarian cancer. The study period ran from the first visit in the outpatient clinic, till 8 weeks later, when the women had either begun chemotherapy or completed their recovery. Ten women participated in two qualitative research interviews each, before and after surgery. By applying a phenomenological-hermeneutic text interpretation methodology, the findings were systematically identified, put into meaning-structures, interpreted and discussed. This process constituted the theme: 'Hoping for the best, preparing for the worst'. Final diagnostics and treatment start were extensive life events, where life itself was threatened, although hope and will were present. The women intuitively prepared themselves for the diagnosis and treatment. However, the ability to prepare was influenced by personal lifestyle, social conditions, coping strategies, and experiences of hope. The ability to prepare could be strengthened by providing adjusted information, psychosocial support and physical optimisation during the perioperative period. By offering targeted family counselling and taking good care of the women's general health and well-being, hope could be sustained and early cancer rehabilitation initiated.

Amphiphilic polyanhydride films promote neural stem cell adhesion and differentiation

Several challenges currently exist for rational design of functional tissue engineering constructs within the host, which include appropriate cellular integration, avoidance of bacterial infections, and low inflammatory stimulation. This work describes a novel class of biodegradable, amphiphilic polyanhydrides with many desirable protein-material and cell-material attributes capable of confronting these challenges. The biocompatible amphiphilic polymer films were shown to release laminin in a stable and controlled manner, promote neural cell adhesion and differentiation, and evade inflammatory responses of the immune system. Using high-throughput approaches, it was shown that polymer chemistry plays an integral role in controlling cell-film interactions, which suggests that these polyanhydrides can be tailored to achieve the desired cell adhesion and differentiation while minimizing immune recognition. These findings have important implications for development of engineered constructs to regulate differentiation and target the growth of transplanted cells in stem cell-based therapies to treat nervous system disorders.

High throughput cell-based screening of biodegradable polyanhydride libraries

A parallel screening method has been developed to rapidly evaluate discrete library substrates of biomaterials using cell-based assays. The biomaterials used in these studies were surface-erodible polyanhydrides based on sebacic acid (SA), 1,6-bis(p-carboxyphenoxy)hexane (CPH), and 1,8-bis(p-carboxyphenoxy)-3,6-dioxaoctane (CPTEG) that have been previously studied as carriers for drugs, proteins, and vaccines. Linearly varying compositional libraries of 25 different polyanhydride random copolymers (based on CPH:SA and CPTEG:CPH) were designed, fabricated, and synthesized using discrete (organic solvent-resistant) multi-sample substrates created using a novel rapid prototyping method. The combinatorial libraries were characterized at high throughput using infrared microscopy and validated using 1H NMR and size exclusion chromatography. The discrete libraries were rapidly screened for biocompatibility using standard SP2/0 myeloma, CHO and L929 fibroblasts, and J774 macrophage cell lines. At a concentration of 2.8 mg/mL, there was no appreciable cytotoxic effect on any of the four cell lines evaluated by any of the CPH:SA or CPTEG:CPH compositions. Furthermore, the activation of J774 macrophages was evaluated by incubating the cells with the polyanhydride libraries and quantifying the secreted cytokines (IL-6, IL-10, IL-12, and TNFalpha). The results indicated that copolymer compositions containing at least 50% CPH induced elevated amounts of TNFalpha. In summary, the results indicated that the methodologies described herein are amenable to the high throughput analysis of synthesized biomaterials and will facilitate the rapid and rational design of materials for use in biomedical applications.

Differences in current clinical features of diploid and triploid hydatidiform mole

OBJECTIVE

To describe and compare the current clinical features of diploid and triploid molar pregnancy and to evaluate whether the presenting clinical features can predict the ploidy of a molar pregnancy.

DESIGN

A retrospective study of the clinical features and ploidy of hydatidiform moles.

SETTING

The Departments of Clinical Genetics and Pathology, Aarhus University Hospital and 13 gynaecological wards, Jutland, Denmark.

POPULATION

A total of 259 women with molar pregnancy diagnosed between April 1986 and June 2003.

METHODS

A review of medical records of consecutively collected, clinically suspected cases of molar pregnancy was performed. The molar ploidy was determined by karyotyping, flow cytometry, and/or analysis of polymorphic DNA markers.

MAIN OUTCOME MEASURES

Maternal characteristics, presenting symptoms, initial human chorionic gonadotrophin (hCG), and molar ploidy.

RESULTS

In a multiple logistic regression model, initial hCG of > or = 100,000 iu/l (P < 0.001), first-trimester gestational age (P < 0.001), vaginal bleeding (P < 0.001), and maternal age of > or = 40 years (P = 0.03) were independent predictors of diploid mole. Women with excessive uterine size more frequently had a diploid than a triploid mole (P < 0.001). Fifty-four percent of the women with triploid mole and 27% of the women with diploid mole were diagnosed before onset of symptoms (P < 0.001).

CONCLUSIONS

The current clinical features of diploid mole are different from those of triploid mole. The presenting clinical profile of a molar pregnancy may be used as an early predictor of the molar ploidy and thus of the prognosis.

Ultrasound and MRI before and after radical hysterectomy: does the operation affect the pelvic floor muscles?

PURPOSE

To evaluate pelvic floor muscles and bladder neck mobility before and after radical hysterectomy for cervical cancer with magnetic resonance imaging (MRI) and ultrasound.

METHODS

A prospective follow-up study of 22 patients studied with MRI and ultrasound preoperatively, three and 12 months after radical hysterectomy was carried out.

RESULTS

Bladder neck mobility was decreased three months postoperatively, but one year after the operation, it had almost attained the preoperative level. The size of the pelvic floor muscles was reduced three months after the operation, but one year postoperatively, muscle size had almost returned to the preoperative level. Age and number of deliveries affected the starting point in muscle size and the mobility of the bladder neck, but the development was identical in all the women.

CONCLUSIONS

We showed that pelvic floor muscle size and mobility of the bladder neck were reduced three months after radical hysterectomy, and that they regenerated to a level only slightly below the preoperative level one year later.

Urogynaecological dysfunction after radical hysterectomy

AIMS

To identify self-reported urogynaecological dysfunctions in women treated by radical hysterectomy, and predict risk factors.

METHODS

A survey using questionnaires. Questionnaires were mailed to 396 patients.

RESULTS

Symptoms of urinary incontinence and urinary retention were reported by more than one-third, respectively. One-third of the patients reported cystitis and dysuria. However, 78% of the women did not consider their symptoms as a problem. Analyses identified body mass index, at least one delivery, pre-operative urinary incontinence, and pulmonary disease as predictors for development of post-operative urinary incontinence. Predictive variables for urinary retention symptoms were age, cystitis and/or dysuria, previous rupture of the anal sphincter, fetal weight at delivery > or =4000 g, sensation of vaginal dryness, and pre-operative urinary retention symptoms. Considering post-operative cystitis and/or dysuria, fetal weight > or =4000 g, sensation of vaginal dryness, cystitis and/or dysuria before the operation, and physical activity were predictive variables.

CONCLUSIONS

Patients can be informed and advised about possible urinary tract symptoms. Special attention in the pre- and post-operative period can be paid to a subgroup of patients at high risk of later urogynaecological problems.

Patients with ovarian cancer have elevated (51)Cr-EDTA plasma clearance early post-operatively

Plasma clearance of (51)Cr-EDTA (Clp(EDTA)) is widely used to determine glomerular filtration rate prior to carboplatin based chemotherapy. We have observed that many patients with ovarian cancer have elevated Clp in the early post-operative phase compared to later phases. The purpose of this study was to examine whether this observation reflects a systematic difference. We retrospectively analysed data from 53 patients who had undergone surgery for ovarian cancer. Twenty-six patients had Clp(EDTA) measured early after the operation (mean, 8 days (range, 3-16 days)) (early group), and 27 patients had Clp(EDTA) measured late post-operatively (mean, 32 days (range, 19-48 days)) (late group). Clp(EDTA) values was measured before the first, third and fifth course of chemotherapy. Additionally, age, height, weight, cancer stage, ascites and tumour histology were noted. Mean Clp(EDTA) in the early group was significantly higher than in the late group (104+/-4.4 vs 89+/-3.5 ml.min(-1) per 1.73 m(2); P =0.005). Clp(EDTA) declined significantly in the early group from the first measurement after the operation until measurement before the third course of chemotherapy but remained constant in the late group. Clp(EDTA) was not correlated to ascites, cancer stage or tumour histology. It is concluded that patients with ovarian cancer have significantly higher Clp(EDTA) in the early post-operative phase than similar patients with Clp(EDTA) measured late post-operatively.

No effects of human relaxin on the active and passive biomechanical properties of isolated cervical specimens from nonpregnant women

OBJECTIVE

To evaluate the effect of human relaxin (hRLX-2) on the active and passive biomechanical properties of cervical tissue in vitro.

MATERIAL

Cervical samples were obtained from the middle part of the cervix in 22 nonpregnant women undergoing hysterectomy.

METHODS

The effect of hRLX-2 (10(-7) M) on the active biomechanical properties was studied on vasopressin (10(-8) M) induced smooth muscle contractions in an organ bath model. The effect on the passive biomechanical properties were studied after incubation of the strips for 48 h with hRLX-2 (10(-8) M and 10(-9) M). Subsequently, the specimens were stretched in a material testing machine until they broke. The load applied and the elongation were simultaneously recorded and the results translated into stress-strain curves.

RESULTS

hRLX-2 did not influence the vasopressin-induced contractility of cervical strips from nonpregnant women in this study. No synergistic effect of progesterone could be demonstrated. The passive biomechanical properties (tensile strength, extensibility, stiffness of failure energy) did not change significantly after relaxin incubation. The results obtained in vitro do not suggest an important physiological effect of relaxin on the human nonpregnant cervix.

Cervical collagen in non-pregnant women with previous cervical incompetence

OBJECTIVE

To study the cervical collagen in non-pregnant women with a history of congenital cervical incompetence.

SUBJECTS

Ten non-pregnant women with congenital cervical incompetence, defined as cervical incompetence in the first pregnancy in a woman without previous cervical trauma. Seventy-one normal non-pregnant women (31 nulligravidae, nine nulliparous and 31 parous women) served as controls.

METHOD

Cervical biopsies were analysed for the hydroxyproline concentration and extractability to express the concentration and the stability of the collagen.

RESULTS

Women with cervical incompetence had markedly lower median cervical hydroxyproline concentration when compared to normal parous women (11.1 (range 6.11-18.5) micrograms/mg wet weight vs. 16.9 (range 7.7-29.8) micrograms/mg wet weight; P = 0.003, Mann Whitney test) and the extractability was almost twice the value found in normal parous women (80.2% vs. 49.5%; P = 0.03, Mann Whitney test). Both pregnancy per ce and parturition caused a significant decrease in the hydroxyproline concentration when compared to values found in nulligravidae (P < 0.0001, Kruskall Wallis test).

CONCLUSIONS

Congenital cervical incompetence seems associated with a low collagen concentration in the cervical connective tissue in the non-pregnant state.

Unmeasurable relaxin concentrations in repeated pregnancies after embryo transfer

Unmeasurable serum relaxin concentrations were found in repeated serum samples taken during two subsequent pregnancies in a woman pregnant after in vitro fertilization in artificial cycles. Despite the absence of relaxin both pregnancies were carried out normally until term except for symptoms of pelvic girdle relaxation. Labour induction was attempted at term as placental insufficiency was suspected. However, the cervical score remained unfavourable and Cesarian section was performed. In the second pregnancy elective Cesarian section was performed due to mild preeclampsia. This case indicates that relaxin may not be important for either suppression of myometrial activity or pelvic girdle relaxation during human pregnancy.

Relaxin is not related to symptom-giving pelvic girdle relaxation in pregnant women

BACKGROUND

The pregnancy associated hormone relaxin induces loosening of the pelvic ligaments in several species. This study was undertaken to evaluate whether pregnant women with symptom-giving girdle relaxation had increased serum relaxin concentrations during pregnancy.

METHOD

Serum relaxin concentrations were measured in 38 pregnant women with symptom-giving pelvic girdle relaxation at the time of diagnosis, in the 30th and 38th week of pregnancy as well as 2 and 6 months after delivery. Fourteen pregnant women without symptoms served as a control group. Relaxin concentrations were measured by a homologous enzyme linked immuno-sorbent assay. All participants were clinically examined including tests for symptom-giving pelvic girdle relaxation.

RESULTS

No differences in serum relaxin concentrations were found throughout pregnancy and after delivery.

CONCLUSION

The present results do not suggest an important role for relaxin in symptom-giving pelvic girdle relaxation during human pregnancy.

Variations in serum relaxin (hRLX-2) concentrations during human pregnancy

STUDY OBJECTIVE

To study variations in serum relaxin concentrations during normal and abnormal human pregnancy and parturition and in umbilical cord blood.

DESIGN AND PATIENTS

Diurnal variations were determined in samples collected every 2 hours for 24 hours (n = 4). Variations during pregnancy were studied in samples taken every 4th week from normal pregnant women (n = 26). Additionally samples were collected once a week from the 37th week of pregnancy and until spontaneously delivery (n = 5). Changes in relaxin during early pregnancy (gestational age: 30 to 97 days) were studied in serum from 12 normal pregnant women, 13 with spontaneous abortion and 38 with an ectopic pregnancy. Fetal serum was obtained at delivery from the umbilical vein (n = 20). All samples were analysed for relaxin by an ELISA based on human relaxin antibodies.

MAIN RESULTS

No diurnal variation in relaxin concentrations were found. In normal pregnant women relaxin concentrations increased during the first 14 weeks of pregnancy. From week 14 to 24 a gradual decrease was found and the concentrations remained constant during the last part of pregnancy. No changes in concentrations were found immediately before or during spontaneous delivery. Women with abnormal pregnancies had lower serum relaxin values than normal early pregnant women. The relaxin concentration was significantly correlated to the serum HCG concentration in early pregnancy but not to the serum HPL levels after week 28. In the umbilical vein relaxin concentrations were low.

CONCLUSION

The variation in circulating levels of relaxin during human pregnancy differs markedly from those found in other species. This suggests a different role for relaxin in human pregnancy.

Morphological, stereological, and biochemical analysis of the mini-pig urinary bladder after chronic outflow obstruction and after recovery from obstruction

Chronic partial bladder outlet obstruction was created in nine mini-pigs by implanting a 6-7 mm ring around the proximal urethra. After a median obstruction period of 63 days, the ring was removed and after a recovery period of median 60 days the animals were sacrificed. Changes in muscle and connective tissue were assessed by unbiased, modern morphometry and biochemical analysis. After obstruction the results were as follows: (1) a 6-fold increase in bladder weight, (2) a 2.5-fold increase in smooth muscle cell size, (3) a 3-fold increase in smooth muscle cell number, (4) unchanged proportions between muscle and connective tissue, (5) unchanged hydroxyproline concentrations, (6) an 8-fold increase in total collagen content, (7) an increase in the ratio of type I/III collagen, and (8) a 7-8-fold increase in total content of type I and III collagen. All changes were markedly, though incompletely, reversed after recovery, except smooth muscle cell number and the ratio of type I/III collagen.

Relaxin (hRLX-2)-induced weakening of human fetal membranes in vitro

We examined the effect of human relaxin (hRLX-2) on the biomechanical properties of human fetal membranes in vitro. Intact chorioamniotic membranes were obtained from twelve elective cesarean sections before the onset of labor. Membrane strips with a fixed width were biomechanically tested after incubation for 20 h with hRLX-2 in concentrations of 10(-7) mol/l and 10(-9) mol/l. Incubation with hRLX-2 (10(-9) mol/l) changed the load-strain values as the membrane stiffness was decreased by 19% when compared with controls: median 2.45 N (range, 0.81-4.31) versus 3.03 N (1.28-5.46), P = 0.02 (Mann-Whitney test). For description of the membrane material as such, the stress-strain values were calculated by dividing the load-strain values with the cross sectional area of the membranes. Incubation with hRLX-2 (10(-9) mol/l) decreased the tensile strength of the membranes by 30%-0.817 N/mm2 (0.282-1.139) vs. 0.575 N/mm2 (0.101-1.150), P = 0.03--and reduced the elastic modulus by 31%--2.26 N/mm2 (0.82-5.08) versus 1.57 N/mm2 (0.51-3.71), P = 0.002. Less pronounced effects were found after incubation with hRLX (10(-7) mol/l). No quantitative or qualitative changes of the membrane collagen were found after relaxin incubation. Although the mechanism for rupture of the fetal membranes remains unknown, the present results suggest that relaxin might be involved in the process leading to rupture of the membranes.

Normal serum relaxin in women with disabling pelvic pain during pregnancy

As part of a case control within cohort study 472 pregnant women answered a questionnaire post partum. Serum relaxin concentrations were measured by a homologous ELISA in samples collected from the women in the 30th week of pregnancy. Serum relaxin concentrations were not associated with pregnancy-associated pelvic pain. Thus, normal pregnant women without pelvic pain (n = 118) had mean concentrations of 343 pg/ml compared to 332 pg/ml in women (n = 59) with pelvic pain and some restriction in daily activities and to 349 pg/ml in women (n = 9) with severe pregnancy-induced pelvic pain. The present results do not suggest a role for relaxin in symptom-giving pelvic relaxation during human pregnancy.

Different biomechanical properties of human fetal membranes obtained before and after delivery

The aim of this study was to elucidate whether the mechanical properties of fetal membranes change during late pregnancy and labour. Membranes delivered by elective caesarean section in week 38 showed different load-strain curves to membranes obtained after spontaneous vaginal delivery at term. A major change in mechanical properties was a decrease in strength of the intact chorioamniotic membrane from 1.39 N to 0.98 N (width of biopsy 4 mm), mainly due to loss of strength of the amniotic component, from 1.27 N to 0.72 N. Moreover, the extensibility of the chorionic component (epsilon Fmax) increased after vaginal delivery from 0.42 to 0.54, resulting in a two-component behaviour of the intact chorioamniotic membrane and further decrease of strength. Based on these observations it is suggested that the amnion is attached to the chorion, act biomechanically in parallel and possess relatively high mechanical strength during pregnancy. After vaginal delivery the two membranes are separated, and pronounced changes are induced in their mechanical properties.

Carcinoma of the cervical stump

Treatment, prognosis, and complication rate were retrospectively studied in 46 patients with cervical stump cancer. There were no differences in clinical stage distribution and histopathological findings between these patients and patients with cervical cancer of the intact uterus. However, 43 patients were treated by radiation therapy and only 3 patients had a cervical amputation. The 5-year survival rate was 62%, which is comparable to that of cervical cancers. Late complications were found in 22 patients: 3 (7%) had symptoms of severe radiation reactions of the bladder (necrosis or vesicovaginal fistels), 14 (31%) had severe radiation reactions in the rectum and the sigmoid (severe proctitis, stenosis, or rectovaginal fistels) and 7 (18%) had large vault necrosis. It is concluded that the frequency of cervical stump cancer is low, but cancer in the cervical stump is difficult to treat and the rate of severe late complications is so high that it should be considered when one is deciding between supravaginal and total hysterectomy. Moreover, screening for cervical cancer should be performed regularly after supravaginal hysterectomy.

Intra-articular fractures at the base of the fifth metacarpal. A clinical and radiographical study of 64 cases

The treatment of 64 intra-articular fractures at the base of the fifth metacarpal was studied. 11 fractures with minimal displacement had been immobilised in a plaster cast without reduction. The position was improved in five of 25 fractures treated by closed reduction and a plaster cast, six of nine fractures after percutaneous pinning, and 12 of 19 fractures after open reduction and internal fixation. At follow-up after a median of 4.3 years, 19 of 50 patients answering a questionnaire had intermittent pain, especially on firm grip. 43 patients were re-examined clinically and radiographically: 21 (49%) had decreased grip power, and 28 had radiographical signs of osteoarthrosis.

Serum relaxin as a potential marker for preterm labour

OBJECTIVE

To determine whether high serum relaxin concentrations in the 30th week of pregnancy were associated with preterm labour.

DESIGN

Case-control study.

SETTING

Two antenatal clinics of the Department of Obstetrics and Gynecology University Hospital of Aarhus.

SUBJECTS

A cohort of 991 women (82% of 1203 eligible) in the 30th week of pregnancy attending one of the two antenatal clinics. The cases comprised 23 (2.4%) women without pre-eclampsia or small for gestational age babies, who were delivered spontaneously before 37 completed weeks gestation. The control group of 46 women was randomly selected from the rest of the cohort, all of them were delivered at term.

INTERVENTIONS

Blood samples were collected at 30 weeks gestation and stored for analysis.

MAIN OUTCOME MEASURES

Serum relaxin concentrations estimated by ELISA technique, length of gestation at delivery.

RESULTS

The mean serum relaxin concentrations in the 30th week of pregnancy was 455 (SD 169) pg/ml and 327 (SD 139) pg/ml in the cases and controls, respectively (P = 0.003, t test). In women with preterm delivery a negative correlation was found between relaxin concentration in the 30th week of pregnancy and the gestational age at parturition (r = -0.53, P = 0.02).

CONCLUSION

High relaxin concentrations may be associated with preterm delivery but the present results need confirmation in large scale studies.

Effects of thiopentone and chlormethiazole on human myometrial arteries from term pregnant women

We have investigated the effects of thiopentone and chlormethiazole on maternal intramyometrial arteries dissected from myometrial biopsies taken during Caesarean section at term. Ring preparations were mounted in organ baths and isometric tension was recorded. Thiopentone 10(-4)-10(-3) mol litre-1 inhibited responses to K+ depolarization, noradrenaline and vasopressin. Chlormethiazole 3 x 10(-5)-3 x 10(-3) mol litre-1 inhibited responses to noradrenaline, while a concentration of 3 x 10(-3) mol litre-1 was required to attenuate responses to vasopressin and K+ depolarization. Neither of the two agents affected relaxant responses to prostacyclin. The results did not yield evidence that clinical use of thiopentone and chlormethiazole should impair uteroplacental vascular perfusion by a direct effect.

Effects of human relaxin on isolated rat and human myometrium and uteroplacental arteries

We investigated the effects of synthetic human relaxin (hRLX-2) on isolated rat and human myometrium and on uteroplacental arteries from term pregnant women. The preparations were mounted in organ baths and isometric tension was recorded. In isolated myometrium from nonpregnant rats, hRLX-2 (10(-10)-10(-7) mol/L) produced concentration-dependent inhibition of contractile activity induced by vasopressin (10(-8) mol/L). In isolated human myometrium from the fundus or isthmus, hRLX-2 (10(-10)-10(-7) mol/L) did not influence spontaneous activity or contractions induced by oxytocin (10(-9) mol/L) and prostaglandin (PG) F2 alpha (10(-5) mol/L). Nor did it influence the tension induced in small intramyometrial arteries by U46619 (10(-7) mol/L), noradrenaline (10(-5) mol/L), and endothelin (10(-9) mol/L); or the tension induced in fetal stem villus arteries by U46619 (10(-7) mol/L), endothelin (10(-9) mol/L), and PGF2 alpha (10(-5) mol/L). The inhibitory effects of hRLX-2 in preparations of rat myometrium were not influenced by the presence of human myometrium in the organ bath or by pre-incubation of hRLX-2 with human myometrium. These results suggest that direct inhibitory effects of relaxin may be of minor importance for the regulation of myometrial activity and uteroplacental circulation in term human pregnancy.

[Local estrogen premedication reduces the abortion time in prostaglandin E1 analogue-induced abortion in the 2nd trimester]

Twenty-eight patients (median gestational age 17 weeks) referred for induction of second trimester abortion, were randomized to intracervical preliminary treatment by either 50 mg 17 beta-oestradiol or placebo. Abortion was then induced by 1 mg prostaglandin E1 vagitories. The preliminary treatment caused a significant rise in cervical score and a significant reduction in induction-abortion time especially by reducing the number of patients with prolonged induction-abortion time.

In vitro analysis of muscular contractile ability and passive biomechanical properties of uterine cervical samples from nonpregnant women

We assessed the maximal muscular contractile ability, the passive biomechanical properties, and the hydroxyproline concentration in uterine cervical tissue samples from 28 nonpregnant women. Circular cervical tissue strips were mounted in organ baths and isometric tension was recorded. The mean (+/- SEM) maximal mechanical responses induced at the length of optimal mechanical performance by K+ (124 mmol/L) equaled 0.16 +/- 0.05 mN/mm2 in the distal cervix and 0.84 +/- 0.47 mN/mm2 in the proximal cervix, as compared with 4.85 +/- 1.0 mN/mm2 in tissues from the isthmus and 6.50 +/- 1.4 mN/mm2 in the fundus. The passive biomechanical properties were analyzed by a materials-testing machine. No significant differences were found between tissues from the distal and proximal cervix or between circular and longitudinal preparations. Tensile strength equaled 1.5-1.7 N/mm2, ie, 10(4)-fold the maximal muscular contractile ability. The extensibility was 0.63-0.76 and the stress-relaxation was 41-48%. The hydroxyproline concentration was 22.5 micrograms/mg wet weight in the distal cervix and 21.6 micrograms/mg in the proximal cervix, as compared with 16.6 micrograms/mg in the isthmus and 12.6 micrograms/mg in the fundus. A method for analysis of the biomechanical properties of the human cervix was designed, and from the measurements obtained it may be concluded that the passive biomechanical strength of the cervix markedly exceeds the active muscular contractile ability. This may be explained by a high collagen concentration and a low content of smooth muscle in the cervical tissue.