Smoking histories: a bioarchaeological approach to tobacco consumption in two skeletal populations from The Netherlands (1300-1829 CE).

Over the past decade, the history of tobacco's introduction to Europe and its societal impact has been extensively studied, resulting in prevailing narratives about its adoption and consumption. In the Netherlands, historical records generally concur that: (I) tobacco rose in popularity among all socioeconomic classes between 1590 and 1630 CE; and (II) it spread throughout the Country as a male habit. However, the presence and consumption of tobacco have exhibited profound variations across diverse societies throughout history, manifesting dissimilar patterns of employment and significance over varying temporal and spatial dimensions. By analysing a sample of 351 human skeletons dating from 1300 to 1829 CE, the present study challenges the limited historical narratives presented above and emphasizes the diverse contextual factors that influenced tobacco's prevalence in two different Dutch centres. Our results suggest that in certain areas of the Netherlands tobacco was likely present and widely consumed well before 1630 CE, while also highlighting overall substantial female participation in the practice. Furthermore, our analysis hints at the possibility of divergent methods of tobacco consumption between sexes, suggesting that the historical narrative of tobacco as solely a male habit may warrant reconsideration. Overall, our study contributes to a deeper understanding of the complex history of tobacco in the Netherlands, shedding light on historical trends and cultural practices.

Precarious adolescence: Adolescent rickets and anterior sacral angulation in two Dutch skeletal collections from the 18th-19th centuries.

OBJECTIVE: This project aims to provide an objective approach to suggesting cases of adolescent rickets using the presence of anterior sacral angulation and interglobular dentine. MATERIALS: Sacra from 49 individuals from Hattem and 150 individuals from Middenbeemster, and second and third molars from five individuals from Hattem were analyzed. Both sites date to the 17th to 19th centuries. METHODS: The sacra were visually assessed for sacral angulation and measured to quantify anterior sacral angulation. The sampled molars were thin sectioned to look for the presence of interglobular dentine. RESULTS: Metric analysis determined that seven individuals had significantly anteriorly angled sacra. Three of the five individuals with sampled molars had interglobular dentine formed during adolescence. CONCLUSIONS: Adolescent rickets may be associated with anterior sacral angulation. SIGNIFICANCE: Anterior sacral angulation may help identify possible cases of adolescent rickets in archaeological human remains. LIMITATIONS: The small sample size for the molars prevented the identification of more individuals with interglobular dentine present during adolescence. Several individuals with visibly angled sacra were unmeasurable due to post-mortem damage and lacked molars. SUGGESTIONS FOR FURTHER RESEARCH: Research on a larger sample would allow us to understand better the association between anterior sacral angulation and adolescent rickets.

DMEK after penetrating keratoplasty: cohort with DMEK grafts and descemetorhexis larger than full-thickness graft.

PURPOSE: The study aims to evaluate visual outcome, central corneal thickness, and rebubbling rate in a cohort with oversized DMEK grafts after failed penetrating keratoplasty (PK). The unique feature of the study is a descemetorhexis diameter larger than the full-thickness graft, i.e., peripheral to the PK interface. METHODS: A monocentric, retrospective evaluation of all patients with endothelial graft failure after PK treated with an oversized DMEK graft and descemetorhexis outside of the PK interface (i.e., in host tissue) between January 2015 and July 2019 at the Department of Ophthalmology at the University of Düsseldorf (Germany) was performed. RESULTS: Eleven eyes of 10 patients were identified. Mean age was 69 years. On average (arithmetic mean ± standard deviation), 1.7 ± 1.0 previous PKs have been performed per eye in this cohort. The mean time between last PK and DMEK was 10.1 ± 7.3 years (range 2 to 23 years). In all cases, the graft diameter exceeded the diameter of the previous PK and descemetorhexis was performed in host tissue, that is, peripheral to the graft-host interface. Rebubbling was performed in 18.2% of the patients (n = 2 eyes) because of central graft detachment. Mean central corneal thickness showed a statistically significant improvement at 5.3 ± 3.5 months after surgery from 688.23 ± 151.01 to 527.75 ± 88 µm (p = 0.002). Visual acuity increased significantly by 5 lines from 1.24 ± 0.5 logMAR (range from 0.5 to 2) to 0.73 ± 0.76 logMAR (range from 0.1 to 2) within 3 months (p = 0.006). Excluding patients without visual potential and transplant failure, visual acuity improved significantly by 8 lines (p < 0.001), and stayed stable until the last follow-up at 15.1 ± 11.4 months (range 6 to 39 months, p < 0.001, n = 8) after surgery. CONCLUSION: DMEK can be successfully used to treat endothelial cell failure after PK, and can provide good postoperative results with regards to visual acuity. This study shows that stripping of Descemet's membrane (DM) peripheral to the PK interface is surgically feasible. Overlapping, larger DMEK grafts with more endothelial cells can be used without increasing rebubbling rates and may potentially improve long-term graft survival.

Medium-grade proteinuria is a risk factor for incident markers of chronic kidney disease.

OBJECTIVE: Medium-grade proteinuria (100-500 mg/g creatinine) is common among people living with HIV/AIDS (PLWHA) but is often undetected or ignored. This prospective, observational cohort study examined medium-grade proteinuria as a risk factor for markers of chronic kidney disease (CKD). METHODS: Quantitative urine samples were collected from 241 PLWHA without known renal disease at baseline between January 2009 and February 2011 and at follow-up 240 weeks later. Multivariate analysis was performed to assess medium-grade proteinuria as a risk factor for incident markers of CKD (estimated glomerular filtration rate < 60 mL/min/1.73 m2 , albuminuria, phosphaturia). RESULTS: Incident markers of CKD were identified in 33 patients (14%), of whom 24 (74%) had medium-grade proteinuria at baseline. Of these, 22 even had proteinuria of < 200 mg/g creatinine. Multivariate analysis showed an adjusted relative risk (aRR) of 2.4 for patients with baseline medium-grade proteinuria to develop signs of CKD. Age was identified as an additional independent predictor. By testing for interaction, tenofovir disoproxil fumarate (TDF)-independent proteinuria was strongly associated with incident CKD markers (aRR = 12.1). CONCLUSION: Medium-grade proteinuria of 100-500 mg/g creatinine is both frequent in PLWHA and a significant risk factor for developing markers of CKD, especially in the absence of TDF. Relevant risk seems to be associated with proteinuria levels as low as 100-200 mg/g creatinine. Current guidelines recommend specific action for proteinuria exceeding 135-200 mg/g but still will miss a relevant number of PLWHA potentially at risk for CKD. An even lower cut-off to trigger nephrological work-up and potentially renoprotective interventions appears to be indicated.

[Health-related quality of life after implantation of a keratoprosthesis with biological haptic]. / Gesundheitsbezogene Lebensqualität nach Implantation einer Keratoprothese mit biologischer Haptik.

BACKGROUND: Many studies report comparatively good long-term results among patients with keratoprostheses with biological haptic. However, overall costs are correspondingly high. A clear cost-benefit relationship is therefore desirable. OBJECTIVE: This study investigates health-related quality of life after implantation of a keratoprosthesis with biological haptic. MATERIALS AND METHODS: We present a retrospective analysis of medical data of 25 patients treated between 1996 and 2006 at the Department of Ophthalmology, University Hospital Homburg/Saar and the Klinikum Offenburg. Health-related quality of life was assessed by means of a questionnaire based on validated instruments, with particular emphasis on physical symptoms, mental health, functional limitations, and social interactions. RESULTS: At a patient age of 49.8 ± 15.7 years (minimum-maximum: 19-78 years; 6 female, 19 male), the mean duration of corneal blindness was 13.8 ± 13.1 years (minimum-maximum: 1-47 years). Changes in visual acuity and subjective satisfaction were statistically significant (p <0.001). Quality of life (on a scale of 1 to 6: median 2) at the time "before the onset of eye disease" and ≥15 months after surgery were identical. Patients with a postoperative visual acuity ≤0.1 (n =11) also showed a statistically significant (p =0.016) benefit in this context. CONCLUSION: The expenditures and costs of keratoprosthetics can be justified by an improvement in the health-related quality of life of the persons concerned. Even a postoperative visual acuity of ≤0.1 correlates with a statistically significant improvement in the subjective quality of life of these patients.

Development of a conjunctival tissue substitute on the basis of plastic compressed collagen.

Ocular surface disorders, such as pterygium, cicatricial pemphigoid and external disruptions, can cause severe inflammation, scarring, fornix shortening as well as ankyloblepharon. Current treatments do not resolve these conditions sufficiently. The aim of this study was to evaluate clinical applicability and suitability of plastic compressed collagen to serve as a substrate for the expansion of human conjunctival epithelial cells in order to develop an epithelialized conjunctival substitute for fornix reconstruction. Human conjunctival epithelial cells were expanded on plastic compressed collagen gels. Epithelial cell characteristics were evaluated by haematoxylin and eosin staining, electron microscopy and cytokeratin expression. The expression of putative epithelial progenitor cell markers p63α, ABCG2 and CK15 was assessed by immunostaining. The proliferative capacity and clonal growth of the cells was evaluated before (P0) and after expansion (P1) on the plastic compressed collagen gels by colony forming efficiency assay. The potential clinical applicability of this gel substitutes was evaluated by assessment of their biomechanical properties as well as their surgical handling. Human conjunctival epithelial cells cultured on plastic and plastic compressed collagen gels formed a confluent cell layer and expressed CK19. The cells showed expression of the putative epithelial progenitor cell markers p63α, ABCG2 and CK15 and sustained colony forming ability. The compressed collagen gels showed a high ultimate tensile strength and elasticity and the surgical handling of gels was comparable to amniotic membrane. An epithelialized conjunctival tissue construct on the basis of compressed collagen might therefore be a promising alternative bioartificial tissue substitute for conjunctival reconstruction. Copyright © 2015 John Wiley & Sons, Ltd.

[New approaches to ocular surface reconstruction beyond the cornea]. / Neue Ansätze zur Rekonstruktion der Augenoberfläche jenseits der Hornhaut.

BACKGROUND: Reconstruction of the conjunctiva is an essential part of ocular surface reconstruction. Clinically applied and experimentally tested tissue- and stem-cell-based approaches are presented and evaluated. MATERIALS AND METHODS: Current literature and our own results will be presented. RESULTS: Autologous conjunctiva, mucous membrane of the mouth or nose, and amniotic membrane are routinely used for conjunctival reconstruction. Limitations are limited availability, involvement in autoimmune diseases, donor heterogeneity, and degradation in an inflamed environment. Experimentally tested matrices as tissues made from extracellular matrix proteins, synthetic polymers, temperature-sensitive culture dishes, and decellularized conjunctiva have been tested in vitro and partly in vivo. To replace conjunctival cells, cells of conjunctiva and mucous membrane of mouth and nose have been evaluated and show progenitor cell properties as well as secretory capacity (goblet cell differentiation). CONCLUSIONS: Although different matrices are available for conjunctival reconstruction there is-due to specific limitations of existing tissues-a need for the development of new therapies for conjunctival replacement. Matrices produced in the laboratory have already been partly investigated in vivo and may thus be clinically applicable in the near future. Adult mucous membrane cells show many properties of conjunctival epithelium after expansion in vitro and thus are a promising cell source for conjunctival tissue engineering. Other stem cells sources require further evaluation.

Cryopreservation and hypothermic storage of lacrimal gland: towards enabling delivery of regenerative medicine therapies for treatment of dry eye syndrome.

Severe dry eye syndrome (DES) can cause painful loss of vision and may result from lacrimal gland dysfunction. Current treatments are palliative, so a causative therapy is desirable. The ability to (cryo)preserve lacrimal gland tissue or epithelial cells would simplify this. Here, lacrimal gland tissue was cryopreserved in 10% dimethylsulphoxide in liquid nitrogen, or stored at 4 °C in culture medium for up to 7 days, and compared with fresh tissue using immunohistochemistry. Cultures were initiated from fresh and stored tissue, and cells characterised in P1 for proliferation (WST-1), colony-forming efficiency (CFE) and secretory capacity (immunocytochemistry and ß-hexosaminidase activity assay). Tissue stored for > 3 days at 4 °C displayed grossly altered tissue architecture when compared with fresh tissue, decreased acinus density and increased caspase-3 activity. Cryopreserved tissue showed less obvious signs of damage without caspase-3 activation. Storage at 4 °C and cryopreservation delayed epithelial outgrowth compared with that from fresh tissue initially (p  < â€…0.05) but, by day 9, all explants showed comparable outgrowth (~90%), except tissue stored at 4 °C for 3 or 7 days (p  < â€…0.05 compared with fresh tissue). Epithelial cell yields per explant were similar from fresh and stored tissue, apart from tissue stored at 4 °C for 7 days (p  < â€…0.01). In P1, epithelial cells from fresh and stored tissue were largely equivalent in terms of: proliferation; CFE (~21%); Rab3D, HexA and lysozyme expression; mucin production; and ß-hexosaminidase activity. These data demonstrate that cryo(preservation) of lacrimal gland tissue and cells is possible, which may enable use of autologous cells in regenerative medicine approaches to treating DES. Copyright © 2016 John Wiley & Sons, Ltd.

Medium-grade tubular proteinuria is common in HIV-positive patients and specifically associated with exposure to tenofovir disoproxil Fumarate.

OBJECTIVES: The aim of this cross-sectional study was to evaluate the prevalence and risk factors of medium-grade proteinuria (100-500 mg/g creatinine) among HIV-positive adults. METHODS: Spot urine samples of HIV-positive adults without known renal disease were analyzed quantitatively between January 2009 and February 2011. Demographic and medical data were collected. Multivariate regression models for different patterns of proteinuria were constructed. RESULTS: Among 411 patients, 18 (4.4 %) presented albuminuria >300 mg/g creatinine and/or proteinuria >500 mg/g creatinine and were excluded from further analyses. Among the study population of 393 patients, 181 (46.1 %) had no significant proteinuria or albuminuria (<100 and <30 mg/g creatinine, respectively), 60 (15.3 %) had moderate albuminuria, while 152 (38.7 %) had proteinuria without albuminuria, suggesting tubular proteinuria. Independent predictors for medium-grade tubular proteinuria in multivariate analysis were exposure to tenofovir (DF), a CD4 nadir <500/µl, older age, and anti-HCV-antibodies. There was no association with classic renal risk factors like diabetes mellitus and arterial hypertension, or with estimated glomerular filtration rate (eGFR). CONCLUSIONS: We detected significant proteinuria in 230 (56.0 %) of 411 HIV-positive patients. Among this group, 152 (66.1 %) had medium-grade proteinuria without albuminuria, which was significantly associated with exposure to tenofovir, older age, a lower CD4 nadir and Hepatitis C. Nephrologic or HIV treatment guidelines fail to detect most of these patients but rather identify patients with high cardiovascular risk. In the absence of an association with eGFR the role of medium-grade tubular proteinuria as a potential early marker of chronic kidney disease remains unclear. Prospective studies are needed.

[Complications of Descemet's membrane endothelial keratoplasty]. / Komplikationen der Descemetmembran-Endothel-Keratoplastik.

Descemet's membrane endothelial keratoplasty (DMEK) is a relatively new, but now established surgical procedure to cure corneal endothelial disorders. However, there are donor- and recipient-associated sources of potential complications, some of which can be identified and addressed prior to the procedure and others that may lead to intra- or postoperative problems. Preoperatively, risk factors for a limited visual outcome (ocular comorbidities, previous ocular surgery, subepithelial/stromal scars) and the specific indication for DMEK should be discussed with the patient. Intraoperatively, young donor age can be associated with a particularly elastic graft, which may be difficult to unfold. Such transplants are not appropriate for particularly difficult recipient situations (very opaque cornea, history of vitreoretinal surgery). Postoperatively, transplant dehiscence is the most common complication, which in many cases can be managed by reinjection of air (or a 20 % SF6 gas/air mix) into the anterior chamber. An elevation of the intraocular pressure after DMEK is often caused by a reaction to topical steroid therapy. Although immune rejections after DMEK are less likely than after Descemet's stripping automated endothelial keratoplasty (DSAEK) and perforating keratoplasty, adequate treatment with topical steroidal drugs is recommended. These common and several rare complications are discussed in this review.

Selective determination of estrogenic compounds in water by microextraction by packed sorbents and a molecularly imprinted polymer coupled with large volume injection-in-port-derivatization gas chromatography-mass spectrometry.

A fully automated protocol consisting of microextraction by packed sorbents (MEPS) coupled with large volume injection-in-port-derivatization-gas chromatography-mass spectrometry (LVI-derivatization-GC-MS) was developed to determine endocrine disrupting compounds (EDCs) such as alkylphenols, bisphenol A, and natural and synthetic hormons in river and waste water samples. During method optimization, the extraction parameters as ion strength of the water sample, the MEPS extraction regime, the volume of organic solvent used for the elution/injection step, the type of elution solvents and the selectivity of the sorbents were studied. For optimum in-port-derivatization, 10 µL of the derivatization reagent N,O-bis(trimethylsilyl)triufloroacetamide with 1% of trimethylchlorosilane (BSTFA+1% TMCS) was used. 17ß-Estradiol-molecularly imprinted polymer (MIP) and silica gel (modified with C-18) sorbents were examined for the enrichment of the target analytes from water samples and the obtained results revealed the high selectivity of the MIP material for extraction of substances with estrogen-like structures. Recovery values for most of the analytes ranged from 75 to 109% for the C18 sorbent and from 81 to 103% for the MIP material except for equilin (on C18 with only 57-66% recovery). Precision (n=4) of the entire analysis protocol ranged between 4% and 22% with both sorbents. Limits of detection (LODs) were at the low ngL(-1) level (0.02-87, C18 and 1.3-22, MIP) for the target analytes.

[Anatomic and subjective success of structured surgical treatment strategy in the management of chronic epiphora - a postoperative analysis of contentment]. / Anatomischer und subjektiver Erfolg einer strukturierten chirurgischen Therapiestrategie zum Management der chronischen Epiphora - eine postoperative Zufriedenheitsanalyse.

BACKGROUND: Epiphora is the result of hypersecretion or reduced tear outflow because of relative or absolute obstruction of the lacrimal system. For the treatment a specific surgical procedure is usually required. Herein we present the subjective and objective findings of 243 consecutive patients with non-irritative induced epiphora, who underwent an operation in a standardised therapy scheme, which is used at the eye departments of the Universities of Lübeck and Würzburg. PATIENTS AND METHODS: In a retrospective cohort study 243 patients were included who underwent lateral tarsal strip (n = 72), external dacryocystorhinostomy (DCR) in the case of an absolute nasolacrimal duct obstruction (NLDO) (n = 116) and relative NLDO (n = 25), DCR with canalicular surgery (n = 18) and simple canalicular surgery (n = 12) with a follow-up of at least 6 month. Common patient and cosmetical satisfaction, intensity of symptoms and further symptoms of 168 patients were evaluated by sending a questionnaire with subsequent telephone survey. Objective findings were recorded from hospital charts. RESULTS: 59.5% of the patients were free of complaints, 19.6% had an absolute decrease of symptoms (epiphora outside and in windy weather) and 20.8 % persistent epiphora (symptoms both in- and outside persisted). 81% of patients with absolute NLDO and 57% with relative NLDO were graded as being free of symptoms, 7% (24%) as a relative decrease and 12% (19%) as a persistence of symptoms. There was a significant difference in success between these indications (p = 0.018). Patency of the lacrimal system assessed by irrigation was found in 95% (absolute NLDO). Commonly, 73.8% were satisfied, 7.7% indifferent and 18.4 % not satisfied. 4 patients were cosmetically not satisfied. CONCLUSIONS: Use of a standardised therapy scheme reduces the symptoms in 79.1% of the patients. In patients with absolute NLDO external DCR achieves an anatomic success rate of 95% and a subjective improvement in 88% with excellent cosmetic results. In comparison with absolute NLDO the success rate of relative NLDO is lower, but still with a subjective improvement in 81%. Our results show that postoperative success depends on the preoperative cause of the epiphora.

Determination of organic priority pollutants and emerging compounds in wastewater and snow samples using multiresidue protocols on the basis of microextraction by packed sorbents coupled to large volume injection gas chromatography-mass spectrometry analysis.

This paper describes the development and validation of a new procedure for the simultaneous determination of 41 multi-class priority and emerging organic pollutants in water samples using microextraction by packed sorbent (MEPS) followed by large volume injection-gas chromatography-mass spectrometry (LVI-GC-MS). Apart from method parameter optimization the influence of humic acids as matrix components on the extraction efficiency of MEPS procedure was also evaluated. The list of target compounds includes polycyclic aromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs), phthalate esters (PEs), nonylphenols (NPs), bisphenol A (BPA) and selected steroid hormones. The performance of the new at-line microextraction-LVI-GC-MS protocol was compared to standard solid-phase extraction (SPE) and LVI-GC-MS analysis. LODs for 100 mL samples (SPE) ranged from 0.2 to 736 ng L(-1) were obtained. LODs for 800 microL of sample (MEPS) were between 0.2 and 266 ng L(-1). In the case of MEPS methodology even a sample volume of only 800 microL allowed to detect the target compounds. These results demonstrate the high sensitivity of both procedures which permitted to obtain good recoveries (>75%) for all cases. The precision of the methods, calculated as relative standard deviation (RSD) was below 21% for all compounds and both methodologies. Finally, the developed methods were applied to the determination of target analytes in various samples, including snow and wastewater.

In sickness and in health: Corneal epithelial stem cell biology, pathology and therapy.

Our window to the world is provided by the cornea on the front surface of the eye. The integrity and functionality of the outermost corneal epithelium is essential for vision. A population of limbal epithelial stem cells (LESCs) are responsible for maintaining the epithelium throughout life by providing a constant supply of daughter cells that replenish those constantly lost from the ocular surface during normal wear and tear and following injury. LESC deficiency leads to corneal opacification, inflammation, vascularization and discomfort (Daniels et al., 2001, 2007). Cultured LESC delivery is one of several examples of successful adult stem cell therapy in patients. The clinical precedence for use of stem cell therapy and the accessibility of the transparent stem cell niche make the cornea a unique model for the study of adult stem cells in physiological conditions as well as in disease.

Conjunctival epithelial cells maintain stem cell properties after long-term culture and cryopreservation.

AIM: Transplantation of tissue-engineered conjunctival epithelial cell sheets has proven to be a promising technique for conjunctival reconstruction. The ability to cryopreserve conjunctival epithelial cells and maintain their stem cell population would improve their availability for clinical use. The aim of this study was to evaluate whether cryopreservation and long-term in vitro culture has an effect on the proliferative capacity and the progenitor-like cell characteristics of conjunctival epithelial cells. METHOD: Human conjunctival cells from bulbar biopsies were isolated and expanded on a growth arrested 3T3 feeder layer. The cells were evaluated for cytokeratin (CK4/CK19) expression by immunostaining. An aliquot with half of the cells from the initial culture was frozen in liquid nitrogen and stored for 14 days and, in addition, donor cells were cryopreserved for more than 6 months (202.7 +/- 13.0 days). Both cryopreserved and noncryopreserved cells were serially cultivated over four passages. For each passage the colony-forming efficiency and the cell population doubling rates were evaluated, and expression of putative progenitor cell markers, p63alpha and ABCG2, was assessed by immunostaining and reverse transcription PCR. RESULTS: Both noncryopreserved and cryopreserved cells demonstrated a high colony-forming capacity that decreased with passage. Cells from both groups underwent approximately 20 cell population doublings before senescence. Immunoreactivity to p63alpha and ABCG2 was found in both groups until passage 4 and their presence was also confirmed by reverse transcription PCR. No difference in cell viability, colony-forming efficiency and immunoreactivity to p63alpha and ABCG2 was observed between cells cryopreserved for 14 days, and more than 6 months (202.7 +/- 13.0 days). CONCLUSION: Conjunctival epithelial cells with progenitor cell-like characteristics can be efficiently cryopreserved and can subsequently maintain their function in vitro over several culture passages. The option to cryopreserve conjunctival cells prior to in vitro expansion would be an advantage when cells have to be cultivated for clinical transplantation.

Membrane-assisted liquid-liquid extraction coupled with gas chromatography-mass spectrometry for determination of selected polycyclic musk compounds and drugs in water samples.

Selected polycyclic musk compounds and drugs were extracted from water samples by membrane-assisted micro liquid-liquid extraction. The two-phase extraction system consisted of polyethylene membrane bags filled with an organic solvent. Chloroform proved to be most suited as acceptor phase to extract caffeine, Galaxolide, Tonalide, phenazone and carbamazepine from aqueous samples. The compounds were enriched from 50 mL sample into a volume of 500 microL of chloroform. Gas chromatography-mass spectrometry (GC-MS) was applied for analysis. The extraction procedure was optimised in regard to membrane material, extraction time and temperature. The evaluation of the entire analysis protocol found limits of detection that ranged from 20 to 200 ng/L. The linear range of calibration covered one magnitude with standard deviations between 4 and 12%. Method comparison with standard analysis techniques such as solid-phase extraction (SPE) combined with GC-MS as well as LC-MS-MS confirmed this method as an easy and reliable protocol, even for the monitoring of matrix-loaded wastewater. The analysis of real samples established the feasibility of the technique.

Nanoclusters in polymer matrices prepared by co-deposition from a gas phase.

This paper reviews the fabrication of organic and metal nanoclusters in polymer matrices by three co-deposition techniques. In particular, the structure and properties of polytetrafluoroethylene (PTFE), polychlortrifluoroethylene (PCTFE), polyparaphenylene sulphide (PPS), polystyrene (PS) and polyparaxylylene (PPX) films, containing gold (Au) and dye clusters are discussed. For the first time, dye-filled polymers and multi-component films, consisting of both Au nanoparticles and dye molecules, dispersed in the PTFE matrix were studied. A low temperature plasma was used for film structure modification. Cluster formation process was studied using optical spectroscopy in situ. Transmission electron microscopy (TEM), atomic force microscopy (AFM) and ellipsometry were used for characterisation of the grown films. During Au-PTFE film growth plasmon band shifted from 460-480 nm to 560 nm. Au cluster diameter was in the 3-7 nm range. Plasma treatment of the vapours led to formation of smaller, but more aggregated clusters. During Au-PPS film deposition a two-step growth mechanism was discovered. At the beginning of film growth the plasmon band at 540 nm appeared, but as thickness increased, the band at 430 nm dominated. Without plasma treatment a disordered mixture was deposited, while with plasma treatment large Au aggregates confined with PPS matrix having plasmon band at 620 nm were formed. Dye cluster formation depends on the dye ability to aggregate, its concentration and the properties of the polymer matrix. But cluster formation can also be tuned by varying the deposition conditions. Laser beam evaporation promoted cluster formation, while plasma treatment and dilution in a polymer matrix prevented cluster formation. In all cases both equilibrium and non-equilibrium film structure can be formed using kinetic factor. Asymmetric molecules with bulky substituents were oriented in polymer matrices by applying an electric field in situ or by corona poling. These molecules did not aggregate even at high dye load. The films exhibited second harmonic generation, which demonstrated chromophore orientation in the polymer matrices.

Lowering the dose of hydroxyurea minimizes toxicity and maximizes anti-HIV potency.

The goal of this study was to optimize the hydroxyurea dosage in HIV-infected patients, and to minimize the toxicity and maximize the antiviral efficacy of the hydroxyurea-didanosine combination. In a randomized, open-label study (RIGHT 702, a multicenter trial performed in private and institutional practices), three daily doses (600 microg, 800-900 microg, and 1200 microg) of hydroxyurea were administered in combination with didanosine and stavudine to 115 chronically HIV-infected patients, one-third antiretroviral drug naive, with viremia between 5000 and 200,000 copies/ml regardless of CD4+ cell count. The primary efficacy end point was the proportion of patients with plasma HIV-1 RNA levels below 400 copies/ml after 24 weeks of therapy. In the RIGHT 702 intent-to-treat population the lowest (600 mg) dose of hydroxyurea was better tolerated, associated with fewer adverse events, and more potent by all efficacy parameters, including the primary end point (76 versus 60% patients with viremia<400 copies/ml at week 24 for the 600-mg and 800- to 900-mg dose groups, respectively; p=0.027), the mean area under the curve (60.3 versus 65.8; p=0.016), and the mean log10 decrease (-1.95 versus -0.77; p=0.001). Patients receiving 600 mg of hydroxyurea daily also had the highest CD4+ cell count, CD4+/CD8+ cell ratio, and lowest CD8+ cell count and percentage (p=0.035). The RIGHT 702 trial provides an explanation for the increased toxicity and decreased efficacy of hydroxyurea when it was used at high dosage (1200 mg daily). At the optimal dosage of 600 mg daily, hydroxyurea, in combination with didanosine, deserves reevaluation for the long-term management of HIV/AIDS worldwide, because of its excellent resistance profile, durability, and affordability.

Education in end-of-life care: bridging disciplinary and institutional boundaries.

This paper describes the development of an interdisciplinary, interinstitutional seminar in palliative care for South Dakota students in medicine, nursing, pharmacy, chaplaincy, and social work. Student outcomes from six seminars conducted during 2001-2004 are reported, and recommendations for future educational efforts are outlined.

Using new structurally related additive schemes in the precalculation of gas chromatographic retention indices of polychlorinated hydroxybiphenyls on HP-5 stationary phase.

A new additive scheme is proposed for the precalculation of gas chromatographic retention indices of complex organic compounds. The principal feature of this approach is the absence of previously calculated I increments for any structural fragments or functional groups in the molecule. Instead, arithmetical operations involving I values of simpler structural analogues of target compounds are used directly. I precalculation for polychlorinated hydroxybiphenyls (839 congeners) on the HP-5 stationary phase was chosen as one of the most important applications of the method under discussion. Such a large number of congeners cannot be obtained as reference samples and their gas chromatographic (GC)-mass spectrometric (MS) identification should therefore be based currently on precalculated I values.