[Experimental investigation of the efficacy of pirfenidone in prevention of ostium cicatricial closure after dacryocystorhinostomy]. / Eksperimental'noe obosnovanie effektivnosti pirfenidona v predotvrashchenii rubtsovogo zarashcheniya iskusstvennogo soust'ya posle dakriotsistorinostomii.

One of the main reasons of failure of dacryocystorhinostomy (DCR) is cicatricial closure of the ostium. Finding a way to prevent this outcome remains one of the leading aims of research in dacryology. The effectiveness of the most widespread methods is often considered contradictory by various researchers. Pirfenidone is a small-molecule agent that demonstrated good antifibrotic effect and low toxicity in previous in vitro research. There haven't been any in vivo studies of its intraoperative use in DCR.Purpose - to determine the in vivo efficacy of pirfenidone in prevention of ostium cicatricial closure following dacryocystorhinostomy in an animal experiment. MATERIAL AND METHODS: The study was conducted on 18 Chinchilla rabbits. They were divided into 3 groups and each animal underwent modified dacryocystorhinostomy. On the final stage of surgery rabbits of group 1 were injected 1 ml of 0.15 mg/ml pirfenidone solution, rabbits of group 2 - 0.3 mg/ml pirfenidone solution. No injections were performed in group 3. Animals were terminated on days 7 (6 rabbits), 14 (6 rabbits) and 28 (6 rabbits) following surgery. Lacrimal stoma patency was evaluated in vivo by irrigation, and morphologically postmortem. Tissue samples obtained from the stoma area were examined histologically for signs of fibrosis. RESULTS: Failure of dacryocystorhinostomy was observed in 4 out of 18 cases: all rabbits of group 3 terminated on days 14 and 28. The most pronounced morphological signs of fibrosis were also noted in group 3. No topical or systemic adverse effects of the medication were observed in groups 1 and 2. CONCLUSION: Pirfenidone demonstrated high antifibrotic efficacy and low toxicity in experimental dacrycystorhinostomy in rabbits. These results provide grounds for further research into the use of pirfenidone in dacrycystorhinostomy.

[The nasal mucosa and outcomes of dacryocystorhinostomy]. / Sostoianie slizistoi obolochki polosti nosa i rezul'taty dakriotsistorinostomii.

OBJECTIVE: To investigate the impact of the nasal mucosa on the outcomes of dacryocystorhinostomy on the basis of morphologic findings. MATERIAL AND METHODS: The investigation enrolled 73 patients who had undergone endonasal endoscopic dacryocystorhinostomy. Nasal mucosal biopsies were intraoperatively taken from all the patients. The obtained samples were subjected to standard histological examination, as well as to immunohistochemical study using an anti-alpha-smooth muscle actin antibody. To determine the intensity of inflammation in the tissue sample, a chronic inflammation score was calculated. The cell elements positively stained with α-smooth muscle actin were estimated using a semi-automatic method. The patients were divided into groups in accordance with the outcome of surgical treatment after 6 months. RESULTS: An unfavorable outcome of dacryocystorhinostomy was observed in 10 (13.7%) patients. The samples obtained from the patients showed a higher chronic inflammation score (8.33%) and a larger number of the cell elements positively stained with α-smooth muscle actin (6026.38±1944.29). The correlation between the outcome of surgical intervention and the quantitative characteristics of myofibroblasts was statistically significant (p<0.05). CONCLUSION: These studies suggest that there is a direct correlation of the efficiency of endonasal endoscopic dacryocystorhinostomy with the presence and degree of chronic nasal mucosal inflammation at baseline.

[Influence of fibrosis mediators on the outcomes of endoscopic endonasal dacryocystorhinostomy]. / Vliianie mediatorov fibroza na rezul'taty éndonazal'noi éndoskopicheskoi dakriotsistorinostomii.

INTRODUCTION: Fibrosis is the most important pathologic condition involved in undesirable outcomes of dacryocystorhinostomy. A number of biochemical factors are currently known to have an effect on wound healing by promoting excessive scarring. Isoforms of transforming growth factor ß (TGF-ß1) are considered the 'main' pro-fibrotic factor, but wound healing is also affected by other cytokines such as connective tissue growth factor (CTGF), which stimulates fibrosis, and fibroblast growth factor (FGF-2), which acts as antagonist to it. PURPOSE: To investigate correlations between endoscopic endonasal dacryocystorhinostomy outcomes and certain mediators of fibrosis. MATERIAL AND METHODS: The study included 45 cases of endoscopic endonasal dacryocystorhinostomy. The patients were grouped according to surgery outcome: patients with unsuccessful surgical treatment were assigned to group 1 (n=10); patients with successful surgical treatment - to group 2 (n=34). One patient was excluded from the study. Full-layer biopsy specimen were taken from patients' nasal mucosa before the surgery. TGF-ß1, TGF-ß2, TGF-ß3, CTGF, FGF-2 concentrations were evaluated using ELISA and normalized by total protein concentration. RESULTS: Surgical failure was observed in 10 cases (22.72%). CTGF concentration was significantly correlated with negative outcome (p<0.05) and was elevated in most specimen obtained from group 1. No significant correlation was noted between the concentrations of other evaluated cytokines in nasal mucosa specimens and the surgical outcome. CONCLUSION: The study found a correlation between CTGF concentration in nasal mucosa and dacryocystorhinostomy outcome, which supports the hypothesis suggested by several authors linking dacryocystorhinostomy failure with chronic inflammation in nasal mucosa.

Branched-chain amino acid catabolism rather than amino acids plasma concentrations is associated with diet-induced changes in insulin resistance in overweight to obese individuals.

BACKGROUND & AIMS: 3-Hydroxyisobutyrate (3-HIB), a catabolic intermediate of the BCAA valine, which stimulates muscle fatty acid uptake, has been implicated in the pathogenesis of insulin resistance. We tested the hypothesis that circulating 3-HIB herald insulin resistance and that metabolic improvement with weight loss are related to changes in BCAAs and 3-HIB. METHODS AND RESULTS: We analyzed plasma and urine in 109 overweight to obese individuals before and after six months on hypocaloric diets reduced in either carbohydrates or fat. We calculated the homeostasis model assessment index (HOMA-IR) and whole body insulin sensitivity from oral glucose tolerance tests and measured intramyocellular fat by magnetic resonance spectroscopy. BCAAs and 3-HIB plasma concentrations were inversely related to insulin sensitivity but not to intramyocellular fat content at baseline. With 7.4 ± 4.5% weight loss mean BCAA and 3-HIB plasma concentrations did not change, irrespective of dietary macronutrient content. Individual changes in 3-HIB with 6-month diet but not BCAAs were correlated to the change in whole body insulin sensitivity and HOMA-IR independently of BMI changes. CONCLUSIONS: 3-HIB relates to insulin sensitivity but is not associated with intramyocellular fat content in overweight to obese individuals. Moreover, changes in 3-HIB rather than changes in BCAAs are associated with metabolic improvements with weight loss. Registration number for clinical trials: ClinicalTrials.gov Identifier: NCT00956566.

Branched-chain and aromatic amino acids, insulin resistance and liver specific ectopic fat storage in overweight to obese subjects.

BACKGROUND & AIMS: Amino acids may interfere with insulin action, particularly in obese individuals. We hypothesized that increased circulating branched-chain and aromatic amino acids herald insulin resistance and ectopic fat storage, particularly hepatic fat accumulation. METHODS AND RESULTS: We measured fasting branched-chain and aromatic amino acids (tryptophan, tyrosine, and phenylalanine) by mass spectrometry in 111 overweight to obese subjects. We applied abdominal magnetic resonance imaging and spectroscopy to assess adipose tissue distribution and ectopic fat storage, respectively. Plasma branched-chain amino acids concentrations were related to insulin sensitivity and intrahepatic fat independent from adiposity, age and gender, but not to abdominal adipose tissue or intramyocellular fat. CONCLUSIONS: In weight stable overweight and obese individuals, branched-chain amino acid concentrations are specifically associated with hepatic fat storage and insulin resistance.

Feasibility and first long-term results after laparoscopic rectal segment resection and vaginal specimen retrieval for deep infiltrating endometriosis.

INTRODUCTION: Radical resection of deep infiltrating endometriosis (DIE), including bladder and bowel resection, provides relief from pain in symptomatic patients. The laparoscopic approach to treatment is well established for bowel resection but normally requires additional abdominal incisions for specimen retrieval. Here we describe our technique of laparoscopically assisted rectal resection and transvaginal specimen retrieval (LARRT) and provide follow-up information on pain scores and complications. MATERIALS AND METHODS: Retrospective observational monocentric study on all DIE patients with rectal infiltration treated between 2008 and 2010 with LATRR at our department. Follow-up was obtained for at least 3 years, including baseline 1-year and 3-year pain scores. RESULTS: We identified four patients undergoing LARRT available for follow-up. DIE was confirmed by histology in all cases. There were no intraoperative complications. Two patients had transient postoperative urinary retention, one patient developed recto-vaginal fistula and required transient colostomy. One patient suffered from persistent vaginal dryness. All patients, however, reported persistent pain relief, including at the end of follow-up period. CONCLUSION: LARRT is a feasible variation of laparoscopic bowel resection for DIE with rectal infiltration. In our study it has promising results with respect to pain control. Larger studies will, however, be required to determine the safety of this procedure.

[Primary treatment of penetrating injuries. Part 1: blast trauma]. / Primärversorgung penetrierender Verletzungen. Teil 1: Explosionstrauma.

Blast injuries may result from a variety of causes but the biomechanical impact and pathophysiological consequences do not differ between domestic or industrial accidents or even terrorist attacks. However, this differentiation relevantly affects the tactical procedures of the rescue teams. Focusing on further detonations, top priority is given to the personal safety of all rescue workers. The rareness of blast injuries in a civilian setting results in a lack of experience on the one hand but on the other hand the complexity of blast injuries to the human body places high demands on the knowledge and skills of the entire rescue team for competent treatment. The purpose of this article is to explain the physicochemical principles of explosions and to convey tactical and medical knowledge to emergency medical services.

Selection of the in vitro culture media influences mRNA expression of Hedgehog genes, Il-6, and important genes regarding reactive oxygen species in single murine preimplantation embryos.

BACKGROUND: The aim of this paper was to determine the influence of different in vitro culture media on mRNA expression of Hedgehog genes, il-6, and important genes regarding reactive oxygen species in single mouse embryos. METHODS: Reverse transcription of single embryos either cultured in vitro from day 0.5 until 3.5 (COOK's Cleavage medium or Vitrolife's G-1 PLUS medium) or in vivo until day 3.5 post coitum. PCR was carried out for ß-actin followed by nested-PCR for shh, ihh, il-6, nox, gpx4, gpx1, and prdx2. RESULTS: The number of murine blastocysts cultured in COOK medium which expressed il-6, gpx4, gpx1, and prdx2 mRNA differed significantly compared to the in vivo group. Except for nox, the mRNA profile of the Vitrolife media group embryos varied significantly from the in vivo ones regarding the number of blastocysts expressing the mRNA of shh, ihh, il-6, gpx4, gpx1 and prdx2. CONCLUSIONS: The present study shows that different in vitro culture media lead to different mRNA expression profiles during early development. Even the newly developed in vitro culture media are not able to mimic the female reproductive tract. The question of long-term consequences for children due to assisted reproduction techniques needs to be addressed in larger studies.

Community-based hepatitis B screening programs in the United States in 2008.

The Centers for Disease Control and Prevention (CDC) recommends hepatitis B surface antigen (HBsAg) testing to identify hepatitis B virus (HBV) infection for foreign-born persons from areas with HBsAg prevalence of > or = 2%. Currently, most HBsAg screening in the United States is performed by independent community organizations. For these HBsAg screening programs, we collected information about the location, number of people screened, other services beyond screening provided, the population/ethnicity groups targeted for screening, and the prevalence of HBsAg among those screened. We identified programs offering screening by contacting programs known to us, from interviews with identified programs, and from structured Internet searches, and collected information using a simple e-mail survey with follow-up phone calls. We identified 55 possible community HBsAg screening programs, of which we successfully contacted 31 programs. In the past year, contacted programs screened an estimated 21 817 patients with an 8.1% average HBsAg prevalence. The majority of programs screened persons born in Asia and their children, and a small number of programs screened persons from Africa or Eastern Europe; very few programs screened U.S.-born persons at risk of HBV infection due to behavioural factors. We identified few or no programs in the American Southeast, the Midwest, and the Southwest outside of California and the Houston area. The HBsAg screening programs that we contacted were effective in identifying and screening patients at risk of HBV as evidenced by the high prevalence observed among those screened. However, their efforts alone are likely insufficient to meet the need for screening recommended by CDC.

A conditionally replicative adenovirus, CRAd-S-pK7, can target endometriosis with a cell-killing effect.

BACKGROUND: Novel therapeutic approaches for endometriosis based on molecular strategies may prove to be useful. Conditionally replicative adenoviruses (CRAds) are designed to exploit key differences between target and normal cells. The wild-type adenovirus (Adwt) promoter can be replaced by tissue-specific promoters, allowing viral replication only in target cells. Viral infectivity can be enhanced by altering Ad tropism via fiber modification. We investigated whether CRAds can be used to target endometriosis and determined the most efficient transcriptional- and transductional-targeting strategy. METHODS: An in vitro study was carried out using human endometriotic cell lines, 11Z (epithelial) and 22B (stromal), normal human ovarian surface epithelial cell line (NOSE006) and primary human endometriosis cells. A total of 9 promoters and 12 Ad tropism modifications were screened by means of a luciferase reporter assay. From this screening data, three CRAds (CRAd-S-pK7, CRAd-S-RGD, CRAd-S-F5/3sigma1, all incorporating the survivin promoter but with different fiber modifications) were selected to perform experiments using Adwt and a replication-deficient virus as controls. CRAds were constructed using a plasmid recombination system. Viral-binding capacity, rates of entry and DNA replication were evaluated by quantitative real-time PCR of viral genome copy. Cell-killing effects were determined by crystal violet staining and a cell viability assay for different concentrations of viral particles per cell. RESULTS: Comparison of promoters demonstrated that the survivin promoter exhibited the highest induction in both endometriotic cell lines. Among the fiber-modified viruses, the polylysine modification (pK7) showed the best infection enhancement. CRAd-S-pK7 was validated as the optimal CRAd to target endometriosis in terms of binding ability, entry kinetics, DNA replication and cell-killing effect. CRAd-S-pK7 also exhibited a high level of DNA replication in primary endometriosis cells. CONCLUSIONS: CRAd-S-pK7 has the best infection and cell-killing effect in the context of endometriosis. It could prove to be a useful novel method to target refractory cases of endometriosis.

Employment of liver tissue slice analysis to assay hepatotoxicity linked to replicative and nonreplicative adenoviral agents.

Whereas virotherapy has emerged as a novel and promising approach for neoplastic diseases, appropriate model systems have hampered preclinical evaluation of candidate conditionally replicative adenovirus agents (CRAds) with respect to liver toxicity. This is due to the inability of human viral agents to cross species. We have recently shown the human liver tissue slice model to be a facile means to validate adenoviral replication. On this basis, we sought to determine whether our ex vivo liver tissue slice model could be used to assess CRAd-mediated liver toxicity. We analyzed and compared the toxicity of a conditionally replicative adenovirus (AdDelta24) to that of a replication incompetent adenovirus (Adnull [E1-]) in mouse and human liver tissue slices. To accomplish this, we examined the hepatic apoptosis expression profile by DNA microarray analyses, and compared these results to extracellular release of aminotransferase enzymes, along with direct evidence of apoptosis by caspase-3 immunhistochemical staining and TUNEL assays. Human and mouse liver tissue slices demonstrated a marked increase in extracellular release of aminotransferase enzymes on infection with AdDelta24 compared to Adnull. AdDelta24-mediated liver toxicity was further demonstrated by apoptosis induction, as detected by caspase-3 immunohistochemical staining, TUNEL assay and microarray analysis. In conclusion, concordance of CRAd-mediated apoptosis in both the human and the mouse liver tissue slice models was demonstrated, despite the limited replication ability of CRAds in mouse liver slices. The results of this study, defining the CRAd-mediated apoptosis gene expression profiles in human and mouse liver, may lay a foundation for preclinical liver toxicity analysis of CRAd agents.

New HIV cases attributable to syphilis in the USA: estimates from a simplified transmission model.

OBJECTIVE: Because syphilis can raise the likelihood of HIV transmission and acquisition, syphilis prevention in the USA has the potential benefit of reducing the number of new cases of HIV. We developed a simplified transmission model to estimate the annual number and cost of new, heterosexually-acquired HIV cases in the USA attributable to syphilis. DESIGN: We estimated the number of heterosexual, HIV serodiscordant partnerships in which syphilis was present in 1996. The model included the probability of transmission of HIV (with and without the presence of syphilis) and other parameters based on data from recent literature. Published direct costs (HIV treatment costs including antiretroviral therapy) and indirect costs (e.g., lost productivity) per case of HIV were used to estimate the annual cost of HIV cases attributable to syphilis. The potential savings in averted HIV costs related to syphilis were used to estimate the potential benefits of a syphilis elimination program. RESULTS: In 1996, an estimated 1082 new heterosexual cases of HIV in the USA could be attributed to syphilis. These cases represented direct costs of US$ 211 million and indirect costs of US$ 541 million; yielding US$ 752 million in total costs. Over 15 years, a syphilis elimination program could save over US$ 833 million (discounted at 3% annually) in averted direct medical costs of syphilis-related HIV infections. CONCLUSIONS: If the only benefit of syphilis elimination were to prevent new HIV cases attributable to syphilis, a national syphilis elimination program costing less than US$ 833 million would probably pay for itself.

Fluorescent lipid oxidation products and heme spectra index antioxidant efficacy in kidney tissue of hamsters.

Studies ranging from epidemiological to molecular suggest that dietary antioxidants protect against chronic diseases. The hypothesis was investigated that hamster kidney homogenate are better protected against induced oxidative damage after animals were fed a purified vitamin E deficient diet supplemented with 30 international units (IU) vitamin E/kg (30 IU diet) than fed the minimum required 3 IU vitamin E/kg (3 IU diet). The addition of 200 mg (+)-catechin to the 3 IU diet may offer protection. The effects of dietary (+)-catechin and alpha-tocopherol on tissue oxidizability were investigated by measuring (i) fluorescent products in lipid extracts, (ii) heme protein oxidation and (iii) heme destruction. A rapid initial increase of oxidation markers was measured over the 4 h incubation period for iron + ascorbate induced oxidation and a constant increase for lipoxygenase catalyzed products. Analysis of covariance over time and comparison at specific incubation times showed that iron + ascorbate induced homogenates from hamsters fed the 30 IU diet generated less fluorescent products and oxidized heme proteins than homogenates from the 3 IU or the 3 IU plus (+)-catechin fed animals. Incubation with lipoxygenase produced more lipid fluorescent products and heme protein oxidation in the 3 IU than in the 30 IU vitamin E group. In conclusion, supplementary dietary vitamin E but not supplementary (+)-catechin in a diet containing the minimum requirement of vitamin E for the species enhances oxidative resistance of kidney tissue.

Variability in the nucleic acid binding site size and the amount of single-stranded DNA-binding protein in Escherichia coli.

The Escherichia coli single-stranded DNA binding protein (SSB), essential for DNA replication, recombination and repair, can undergo a thermally induced irreversible conformational change which does not eliminate its biological activity, but changes the number of nucleotides it covers (binding site size) when binding to a single-stranded nucleic acid lattice. The binding site size of native and conformationally changed SSB was also found to be a function of the molecular mass of the polynucleotide, an observation which is unusual for single-stranded DNA binding proteins and will greatly affect the affinity relationship of this protein for nucleic acids. A radioimmunoassay used to quantitate in SSB level in cells revealed the number of SSB tetramers to be larger than initial estimates by a factor of as much as six. All these data suggest that the biological role of SSB and its mechanism of action is by far more complex than originally assumed.

Cocoa inhibits platelet activation and function.

BACKGROUND: Epidemiologic studies have shown inverse associations between dietary polyphenols and mortality from coronary heart disease. However, the basis for this protective association is uncertain. Food polyphenols reportedly have antioxidant properties and decrease platelet function in vitro. OBJECTIVE: This study sought to evaluate whether consumption of a polyphenol-rich cocoa beverage modulates human platelet activation and primary hemostasis. DESIGN: Peripheral blood was obtained from 30 healthy subjects before and 2 and 6 h after ingestion of a cocoa beverage (n = 10), a caffeine-containing control beverage (n = 10), or water (n = 10). Platelet activation was measured in terms of expression of activation-dependent platelet antigens and platelet microparticle formation by using fluorescent-labeled monoclonal antibodies and flow cytometry. Primary platelet-related hemostasis was measured with a platelet function analyzer. RESULTS: Ex vivo epinephrine- or ADP-stimulated expression of the fibrinogen-binding conformation of glycoprotein IIb-IIIa was lower 2 and 6 h after consumption of cocoa than before consumption. Cocoa consumption also decreased ADP-stimulated P-selectin expression. In contrast, epinephrine-induced platelet glycoprotein IIb-IIIa expression increased after consumption of the caffeine-containing beverage but not after water consumption. Platelet microparticle formation decreased 2 and 6 h after cocoa consumption but increased after caffeine and water consumption. Primary hemostasis in response to epinephrine in vitro was inhibited 6 h after cocoa consumption. The caffeine-containing beverage inhibited ADP-induced primary hemostasis 2 and 6 h after consumption. CONCLUSIONS: Cocoa consumption suppressed ADP- or epinephrine-stimulated platelet activation and platelet microparticle formation. Cocoa consumption had an aspirin-like effect on primary hemostasis.

Effect of dietary catechin and vitamin E on aortic fatty streak accumulation in hypercholesterolemic hamsters.

Male golden Syrian hamsters were fed for 16 weeks on a hypercholesterolemic diet containing, per kg, 150 g of lipids (90 g butterfat, 35 g vitamin E-stripped corn oil and 25 g fish oil), 2 g cholesterol and either 3 IU vitamin E (3 IU E), 3 IU vitamin E and 200 mg catechin hydrate (3 IU E-200 Cat) or 30 IU vitamin E (30 IU E). More fatty streaks, measured by Oil Red O staining, were deposited in aortas of hamsters fed 3 IU E than in those fed either 3 IU E-200 Cat or 30 IU E. Lipid staining increased with plasma low-density lipoprotein cholesterol (LDL-C) in all animals. At the same concentration of LDL-C, animals fed either 3 IU E-200 Cat or 30 IU E developed less fatty streaks than those fed 3 IU E. Plasma LDL-C and total cholesterol were highest in hamsters fed 3 IU E and LDL-C and total cholesterol in animals fed 3 IU-200 Cat were not different from those fed either 3 IU E or 30 IU E. This study showed the importance of circulating plasma LDL-C on atherogenesis and the inhibitory effect on this process of both dietary vitamin E and catechin.

In vivo biostability of a polymeric hollow fibre membrane for cell encapsulation.

The biostability of poly(acrylonitrile-co-vinyl chloride) (P(AN/VC)) hollow fibre membranes was assessed in the rat peritoneal cavity over a 12 month period. The mechanical and chemical stabilities of the hollow fibre membrane (HFM) were characterized by measuring its tensile strength and molecular weight (by gel permeation chromatography) pre-implantation and post-explantation. The stability of the HFM transport properties was determined by molecular weight cut-off (MWCO) and hydraulic permeability (HP). Explanted HFMs were treated with 4 M NaOH to remove adsorbed protein before measuring mechanical, chemical and transport properties. The HFM was stable in vivo for at least 12 months: (i) weight average molecular weight (Mw) at t = 0 was 143,000 g mol-1 (with a polydispersity index (PDI) of 2.3) and at t = 12 months it was 128,000 g mol-1 (with a PDI of 2.8); and (ii) tensile strength at t = 0, 52 +/- 2 mdyne, did not change significantly over time and was 46 +/- 7 mdyne at t = 15 months (P > 0.05 by a two-tailed Student's t-test); and (iii) no significant differences, with respect to standard deviation, were observed in the transport properties: HP was 7.4 +/- 1.5 ml min-1 m-2 mmHg-1 at t = 0 and 7.5 +/- 1.5 ml min-1 m-2 mmHg-1 at t = 12 months, while MWCO (at 90% rejection) was initially 40,000 +/- 8000 g mol-1 and then 54,000 +/- 10,000 g mol-1 at t = 12 months.

Transport characterization of membranes for immunoisolation.

This study relates to the diffusive transport characterization of hollow fibre membranes used in implantable bio-hybrid organs and other immunoisolatory devices. Techniques were developed to accurately determine the mass transfer coefficients for diffusing species in the 10(2)-10(5) MW range, validated and then used to study one membrane type known to effectively immunoisolate both allografts and xenografts in vivo. Low-molecular-weight diffusing markers included glucose, vitamin B12 and cytochrome C; higher-molecular-weight molecules were bovine serum albumin, immunoglobulin G, apoferritin and a range of fluorescein-tagged dextrans. Overall and fractional mass transfer coefficients through the hollow fibres were determined using a resistance-in-series model for transport. A flowing dialysis-type apparatus was used for the small-molecular-weight diffusants, whereas a static diffusion chamber was used for large-molecular-weight markers. For diffusion measurements of small-molecular-weight solutes, convective artefacts were minimized and the effect of boundary layers on both sides of the membrane were accounted for in the model. In measuring diffusion coefficients of large-molecular-weight species, boundary layer effects were shown to be negligible. Results showed that for small-molecular-weight species (< 13,000 MW) the diffusion coefficient in the membrane was reduced relative to diffusion in water by two to four times. The diffusion rate of large-molecular-weight species was hindered by several thousand-fold over their rate of diffusion in water.

Dose control with cell lines used for encapsulated cell therapy.

Cell therapy-use of cells to deliver active factors-is an emerging technique in treatment of neurodegenerative disease. Successful devices maintain cell viability and functionality over extended implant periods. Use of dividing cell lines to deliver therapeutic factors has been studied extensively. One emerging issue is the tendency of cells to continue proliferation within the intracapsular environment-potentially outstripping nutrient supply. This work presents a method of controlling proliferation and delivering therapeutic molecules within a dose range. The method entails encapsulation into a hollow fiber device of discrete numbers of cell-containing microcarriers. Proliferation control is attained by embedding cell-containing microcarriers in nonmitogenic hydrogels. PC-12 cells secreting L-dopa and dopamine was the model cell line tested. Feasibility of the method in controlling growth of normally rapidly dividing cells in the intracapsular environment was demonstrated in vitro and in vivo. Control nonmicrocarrier PC-12 cell devices had approximately fourfold greater expansion in cell number compared to experimental microcarrier-containing devices over 4 weeks in vitro and in vivo after implant into rat striatum. Ability to control dose released over a several-fold range was demonstrated with encapsulated PC-12 cells delivering neurotransmitters and C2C12 mouse myoblast cells delivering neurotrophic factors (CNTF).

Expression of the hyaluronan receptor RHAMM in endometrial carcinomas suggests a role in tumour progression and metastasis.

PURPOSE: Interactions of hyaluronic acid (HA) with its binding protein RHAMM (receptor for HA-mediated motility) have been proposed as being important in promoting tumour progression and dissemination. This comparative study was designed to investigate the RHAMM expression patterns in endometrial carcinoma. METHODS: We examined a series of 89 endometrial carcinomas and 15 normal endometrial tissues by immunohistochemistry, using a RHAMM-specific polyclonal antibody. Expression of RHAMM was assessed according to the pattern and intensity within (overall cytoplasm, center/periphery of tumours) and between the tumours. The staining results were compared to the corresponding clinical data (age, menopause status, histological staining, histological grading, lymph node status). RESULTS: RHAMM-expression was detectable in 58% of the 89 tumours [Histological stage: pT1a (8/12); pT1b (16/37); pT1c (18/26); pT2 (6/9); pT3a (4/5)] and 13% (2/15) of the normal endometrial tissues. The positivity rates for RHAMM were 100% in patients with positive lymph nodes but only 50.7% in patients with negative lymph nodes ( P<0-01). Additionally, the expression pattern showed a highly significant correlation ( P<0.01) with the histological grade of the tumours [G1 (6/42), G2 (33/34), G3 (13/13)] and occurrence of lymph node metastases. CONCLUSIONS: Our results suggest that RHAMM expression may enhance and improve the invasion and metastasis of endometrial carcinomas.