Cost-Effectiveness of Onasemnogene Abeparvovec Compared With Nusinersen and Risdiplam in Patients With Spinal Muscular Atrophy Type 1 in Brazil: Custo-Efetividade do Onasemnogeno Abeparvoveque (AVXS-101) em Comparação ao Nusinersena e Risdiplam em Pacientes com Atrofia Muscular Espinhal Tipo 1 no Brasil

OBJECTIVES

This study aimed to evaluate the cost-effectiveness of the onasemnogene abeparvovec in relation to nusinersen and risdiplam in the treatment of spinal muscular atrophy type 1 from the perspective of the Brazilian Unified Health System.

METHODS

A Markov model was built on a lifetime horizon. Short-term data were obtained from clinical trials of the technologies and from published cohort survival curves (long term). Costs were measured in current 2022 local currency (R$) values and benefits in quality-adjusted life-years (QALYs). Utility values were derived from type 1 spinal muscular atrophy literature, whereas costs related to technologies and maintenance care in each health state were obtained from official sources of reimbursement in Brazil. Deterministic and probabilistic, as well as scenario, sensitivity analyses were performed.

RESULTS

Compared with the less costly strategy (nusinersen), the use of onasemnogene abeparvovec resulted in an incremental cost of R$2.468.448,06 ($975 671.169 - purchasing power parity [PPP]) and a 3-QALY increment and incremental cost-effectiveness ratio of R$742.890,92 ($293 632.774 - PPP)/QALY. Risdiplam had an extended dominance from other strategies, resulting in an incremental cost-effectiveness ratio of R$926.586,22 ($366 239.612 - PPP)/QALY compared with nusinersen. Sensitivity analysis showed a significant impact of the follow-up time of the cohort and the cost of acquiring onasemnogene abeparvovec.

CONCLUSIONS

Over a lifetime horizon, onasemnogene abeparvovec seems to be a potentially more effective option than nusinersen and risdiplam, albeit with an incremental cost. Such a trade-off should be weighed in efficiency criteria during decision making and outcome monitoring from the perspective of the Brazilian Unified Health System.

[Mandibular fractures in cattle - a review of 108 cases]

INTRODUCTION

Mandibular fractures are among the most common fractures in cattle. The medical records of 108 cattle with a mandibular fracture, that were referred to the University of Zurich Veterinary Hospital from 2005 to 2019, were analysed to document the types of treatment, complications and long-term outcomes. Cattle, still alive at the time of retrospective analysis, underwent clinical and radiographic examinations. A fall was the single most common cause of a mandibular fracture (48,1 %), and a third of all cattle had a concomitant disease at the time of referral. Seventy-five cattle (69,4 %) had a single fracture, 26 (24,1 %) had two fractures and seven (6,5 %) had three fractures of the mandible. The molar part of the mandibular body was most commonly (40,7 %) fractured followed by the diastema (23,6 %), the pars incisiva (13,4 %), the ramus (12,1 %) and the symphysis (10,2 %) of the mandible. The majority of cattle (84/108, 77,8 %) had open fractures. Treatment was instituted in 63/108 animals (58,3 %) with 77/148 fractures. Of these fractures, 28 were treated with plate osteosynthesis, 25 with an external fixator, 8 with cerclage wire, 7 using mixed techniques, 4 with fragment excision, 4 underwent conservative treatment and one a mucosal suture. In total, 45/108 animals (41,7 %) were culled because of multiple fractures, concomitant diseases and because of economic reasons. Complications occurred in 34 (54,0 %) treated cattle; 22 had abnormal wound healing of which 18 developed osteomyelitis complicated by a sequestrum (14). Of the treated 63 cattle, 56 (88,9 %) were discharged. The mean postoperative productive life was 46 ± 29,2 months for animals that were deceased at the time of the study. Thirteen of the cattle with a sequestrum remained in the herd for 15 to 92 months (mean, 47 months) and one for 2 months. The life expectancy after treatment did not differ significantly from that of the Brown Swiss and Swiss Holstein dairy cattle populations, where the cattle of this study mainly came from. Eleven cattle were available for long-term follow-up; all had a good general health status but nine had dental abnormalities including missing teeth, steps or enamel points, which did not noticeably affect the body condition of the animals. Surgical treatment of selected mandibular fractures had a favourable prognosis (52/63 healed, 82,5 %) in cattle.

Guidelines for Utility Measurement for Economic Analysis: The Brazilian Policy

INTRODUCTION

Health-related quality of life is expressed in utilities, also referred to as utility estimates or parameters. Considerations about the source and type of utility values are especially important in a modeling context, where the lack of transparency, including the lack of a hierarchy for utility data sources, is a major issue to any estimation and can potentially compromise model reliability.

OBJECTIVES

This document aims to present the first version of the Brazilian guidelines for utility measurement to support economic analysis.

METHODS

A virtual workshop and a modified Delphi panel with 10 health technology specialists followed a rapid evaluation of 110 technical documents and indexed publications. The recommendations are based on the proposition that has received the most votes, although contentious issues are addressed in the suggestion or discussion. The rationale for the final decision is included in the text.

RESULTS

The consensus includes 50 recommendations with the following topics: Transparency and Reliability, Model Design, Conditions Under Which Generic Questionnaires Are Not Sensible or Valid, Utility Evidence Hierarchy, Utility Data Searching, Modeling Utility Values, Extrapolating Quality Adjusted Life-Years for Models With Lifetime Horizons, Caregiver Utility, Utility Data Synthesis, Quality/Certainty of the Evidence, and Utility Estimates in End-of-Life Conditions.

CONCLUSIONS

The goal of this project is to create unified national standards for using utility metrics in economic analysis in Brazil. This set of recommendations is not obligatory, but it is meant to serve as a guide and lead to the development of better and more transparent economic models in the country.

DDRE-48. COMPARTMENT LOCKED IL-12 - INCREASED TISSUE RETENTION AND MINIMAL PERIPHERAL EXPOSURE ALLOW HIGHER TREATMENT EFFICACY AND TOLERABILITY IN LOCAL GLIOBLASTOMA THERAPY

Recent clinical studies in glioblastoma (GBM) highlight the potential of local IL-12 therapy, but they also bring back tolerability concerns due to leakage into the periphery. This leakage might thus hamper exploiting the full potential of local IL-12 therapy. Fusion with an IgG4 Fc portion increases the tissue retention of IL-12; but could also confer export into the blood and subsequent systemic recycling through the neonatal Fc receptor (FcRn), ultimately leading to potentially toxic IL-12 serum levels. We assessed the expression of FcRn in human and murine GBM and its role in IL-12Fc tissue retention and systemic exposure upon local delivery. Human or murine IL-12Fc was injected in GBM-bearing or naïve wt or FcRn-humanized mice continuously or as bolus via convection-enhanced delivery (CED). We screened combinations of amino-acid substitutions at the (IL-12)Fc:FcRn binding interface to abolish this interaction. Brain and blood concentrations were assessed via ELISA or cytokine bead arrays. FcRn affinity was measured by SPR/ELISA and bioactivity tested on PBMCs and human GBM explant cultures. Treatment efficacy and immunological correlates were assessed in GBM bearing mice. FcRn is upregulated in human and mouse GBM and contributes to brain export and subsequent peripheral recycling of IL-12Fc in the blood. IL-12Fc with abrogated FcRn binding due to a unique set of substitutions is fully functional and appears brain compartment locked (CL IL-12) as it exhibits enhanced tissue retention and reduced serum levels upon local injection, reaching up 100x higher brain to serum concentration ratios than regular IL-12. Compared to its non-modified counterpart, murine CL IL-12 shows significantly higher treatment efficacy at negligible systemic footprint in late stage murine GBM. In patient explant cultures, human CL IL-12 leads to successful inflammatory conditioning. Compartment locked IL-12 should thus allow a wide dosing window to fully harness its therapeutic potential for local GBM therapy.

Projection of COVID-19 intensive care hospitalizations in the Federal District, Brazil: an analysis of the impact of social distancing measures

OBJECTIVE

To build scenarios and analyze the impact of social distancing policies on the spread of COVID-19 and the need for intensive care unit beds.

METHODS

Three dissemination scenarios were built according to level of adherence to social distancing measures in the context of Brazil's Federal District, based on a dynamic transition compartmental model and Monte Carlo simulations. The model's parameter values were based on official sources, indexed bibliographic databases and public data repositories.

RESULTS

The favorable scenario, with constant 58% adherence to social distancing, estimated a peak of 189 (interquartile range [IQR]: 57 - 394) ICU hospitalizations on March 3rd2021. Absence of social distancing would result in an unfavorable scenario with a peak of 6,214 (IQR: 4,618 - 8,415) ICU hospitalizations probably as soon as July 14th2020.

CONCLUSION

The projections indicate the high impact of social distancing measures and emphasize the applicability of public indicators for COVID-19 monitoring.

Study of Two-Photon Exchange via the Beam Transverse Single Spin Asymmetry in Electron-Proton Elastic Scattering at Forward Angles over a Wide Energy Range

We report on a new measurement of the beam transverse single spin asymmetry in electron-proton elastic scattering, A_{⊥}^{ep}, at five beam energies from 315.1 to 1508.4 MeV and at a scattering angle of 30°<θ<40°. The covered Q^{2} values are 0.032, 0.057, 0.082, 0.218, 0.613 (GeV/c)^{2}. The measurement clearly indicates significant inelastic contributions to the two-photon-exchange (TPE) amplitude in the low-Q^{2} kinematic region. No theoretical calculation is able to reproduce our result. Comparison with a calculation based on unitarity, which only takes into account elastic and πN inelastic intermediate states, suggests that there are other inelastic intermediate states such as ππN, KΛ, and ηN. Covering a wide energy range, our new high-precision data provide a benchmark to study those intermediate states.

One-Year stable perovskite solar cells by 2D/3D interface engineering

Despite the impressive photovoltaic performances with power conversion efficiency beyond 22%, perovskite solar cells are poorly stable under operation, failing by far the market requirements. Various technological approaches have been proposed to overcome the instability problem, which, while delivering appreciable incremental improvements, are still far from a market-proof solution. Here we show one-year stable perovskite devices by engineering an ultra-stable 2D/3D (HOOC(CH₂)₄NH₃)₂PbI₄/CH₃NH₃PbI₃ perovskite junction. The 2D/3D forms an exceptional gradually-organized multi-dimensional interface that yields up to 12.9% efficiency in a carbon-based architecture, and 14.6% in standard mesoporous solar cells. To demonstrate the up-scale potential of our technology, we fabricate 10 × 10 cm² solar modules by a fully printable industrial-scale process, delivering 11.2% efficiency stable for >10,000 h with zero loss in performances measured under controlled standard conditions. This innovative stable and low-cost architecture will enable the timely commercialization of perovskite solar cells.

Up-scaling represents a key challenge for photovoltaics based on metal halide perovskites. Using a composite of 2D and 3D perovskites in combination with a printable carbon black/graphite counter electrode; Grancini et al., report 11.2% efficient modules stable over 10,000 hours.

Donor-π-donor type hole transporting materials: marked π-bridge effects on optoelectronic properties, solid-state structure, and perovskite solar cell efficiency

Donor–π-bridge–donor type oligomers (D–π–D) have been studied intensively as active materials for organic optoelectronic devices.

Donor–π-bridge–donor type oligomers (D–π–D) have been studied intensively as active materials for organic optoelectronic devices. In this study, we introduce three new D–π–D type organic semiconductors incorporating thiophene or thienothiophene with two electron-rich TPA units, which can be easily synthesized from commercially available materials. A thorough comparison of their optoelectronic and structural properties was conducted, revealing the strong influence of the extent of longitudinal π-bridge conjugation on both the solid structure of the organic semiconductive materials and their photovoltaic performance when applied as hole transporting materials (HTM) in perovskite solar cells. Single-crystal measurements and time-resolved photoluminescence (TRPL) studies indicate that these coplanar donor–π–donor type HTMs could be promising alternatives to state-of-the-art spiro-OMeTAD, due to the multiple intermolecular short contacts as charge transporting channels and efficient charge extraction properties from the perovskite layer. The optimized devices with PEH-9 exhibited an impressive PCE of 16.9% under standard global AM 1.5 illumination with minimized hysteretic behaviour, which is comparable to that of devices using spiro-OMeTAD under similar conditions. Ambient stability after 400 h revealed that 93% of the energy conversion efficiency was retained for PEH-9, indicating that the devices had good long-term stability.

[Primary malignant melanoma arising from the base of the tongue: a case report]

Primary mucosal melanoma is a biologically aggressive neoplasm, which is rarely located at the base of the tongue. The absence of early signs and symptoms, the lack of an evidence-based treatment, the early development of metastases and high rates of local recurrence contribute to the overall poor prognosis of these melanomas. This paper reports the case of a 66-year-old male presenting with local recurrence of a primary melanoma of the base of the tongue.

[Anticoagulation during pregnancy following an artificial heart valve replacement]

HISTORY AND CLINICAL FINDINGS

A 23-year-old woman had received a mechanical bileaflet mitral valve prosthesis because of severe mitral valve insufficiency caused by an acute bacterial endocarditis with vegetations. One year after the operation the patient suffered on two miscarriages under oral anticoagulation by phenprocoumon. Present, she was referred to our center with the question of conversion to low molecular weight heparine because of continued yearning for a baby.

INVESTIGATIONS

At admission the woman was in good general and nutritional condition. Echocardiography showed a regular prosthetic function. Blood analysis, electrolyte parameters and enzyme values were normal, further laboratory investigations revealed a factor-V-Leiden-mutation. A chromosomal analysis detected no aberrations.

TREATMENT AND COURSE

The oral anticoagulation by phenprocoumon was switched to subcutaneous low molecular weight heparine in therapeutical dosage. Anti-factor-Xa-activity was controlled at regular intervals. Further pregnancy was uneventful for both, mother and child. A healthy infant was born by caesarean section at 40 (th) week of gestation.

CONCLUSIONS

Treatment with anticoagulation by phenprocoumon is indispensable for mechanical heart valve protheses. Conversion to low molecular weight heparine is possible in patients who insistent request to conceive. The anticoagulation by low molecular weight heparine avoids teratogenic effects during pregnancy because the placenta is impermeable to that heparin. Furthermore, prophylaxis of thromoses by low molecular weight heparine is probably in almost the same manner as by phenprocoumon.

Peak inspiratory flow through the Genuair inhaler in patients with moderate or severe COPD

The Genuair inhaler is a new multidose dry powder inhaler for the delivery of aclidinium bromide - a novel, long-acting, muscarinic antagonist in development for the treatment of chronic obstructive pulmonary disease (COPD). The primary aim of this study was to assess the inspiratory flow characteristics through Genuair in patients with moderate or severe COPD. Using a three-period cross-over design, 48 patients were randomised to inhale placebo powder through Genuair, HandiHaler A (slow, deep inhalation as per manufacturer's instructions) or HandiHaler B (fast, forceful inhalation). Three measurements of peak inspiratory flow (PIF), 10min apart, were recorded for each method of administration. The highest and average PIFs for the three attempts (mean+/-standard deviation) generated through the Genuair inhaler were 97.7+/-15.7 and 92.0+/-15.4L/min, respectively. Furthermore, 97% of inhalations with the Genuair inhaler were successful (activation of trigger threshold mechanism) and optimal (PIF> or =45L/min). The highest and average PIFs generated through HandiHaler A and B were significantly lower than with the Genuair inhaler. In conclusion, patients with moderate or severe COPD were able to generate sufficient inspiratory airflow through the Genuair inhaler to reliably inhale the full dose and reset the inhaler.

Thermochemical analysis of the dissolution process of Griseofulvin

Very often poor water solubility limits the therapeutic use of drug molecules. In order to develop strategies to overcome this handicap a basic understanding of this phenomenon is needed. In this paper Griseofulvin is used as a model substance. According to the Hess theorem the direct dissolution of Griseofulvin is replaced by a series of alternative processes which in their combination have the same starting point as well as the same endpoint as the direct dissolution. The energies associated with these alternative processes however can be determined more exactly than the dissolution energy. In cases where the measurement of an energy is impossible, e.g. the transfer energy of single molecules from the vapor phase into water, this energy is calculated by quantum chemical methods. In addition these alternative processes allow for a better understanding of the elementary steps involved in the dissolution process. The energies determined for the various alternative processes are compared with the dissolution energies as calculated by means of AMSOL. An excellent agreement can be observed.

Pulmonales und kardiales Rezidiv einer Sarkoidose nach Herztransplantation

HISTORY

A 38-year-old man underwent heart transplantation for end-stage heart failure as a result of sarcoid cardiomyopathy. Routine post-transplantation endomyocardial biopsies demonstrated no graft rejection. However, six months post-transplantation, while on immunosuppressive medication, the patient noted a dry cough.

INVESTIGATIONS

Cardiovascular magnetic resonance imaging (MRI) showed recurrent sarcoidosis in the transplanted heart, and bronchoscopy revealed granulomas consistent with pulmonary sarcoidosis. The chest radiograph revealed bilateral perihilar interstitial nodular infiltration. Whole blood analysis, coagulation and electrolyte parameters as well as inflammatory and enzyme values were within the normal range.

TREATMENT AND COURSE

The patient was treated with an increased dosage of prednisone. Furthermore, the immunosuppression with cyclosporin and everolimus was replaced by cyclosporin and azathioprine. Regular pulmonary function tests were done in addition to the routine biopsy controls and the laboratory tests as well as electrocardiography, echocardiography and radiography. The patient has remained well at eighteen months after transplantation.

CONCLUSIONS

For those patients who develop end-stage cardiomyopathy from sarcoidosis, heart transplantation is still the therapy of choice. The recurrence of sarcoidosis in a transplanted heart has been only very rarely reported in the literature. Once recurrence is diagnosed patients should be treated with an increased dosage of steroid in addition to standard immunosuppressives.

The Arabidopsis GNARLED gene encodes the NAP125 homolog and controls several actin-based cell shape changes

In plants many aspects of cell shape regulation are controlled by actin-dependent processes. The ARP2/3 complex has been recognized as a regulator of actin organization. Mutations in genes encoding components of the ARP2/3 complex lead to cell shape defects in several cell types, including trichomes, epidermal pavement cells and hypocotyl cells. We show here that mutations in the GNARLED (GRL) gene cause a similar range of phenotypes. The GRL gene encodes the Arabidopsis homolog of NAP125, which in animals is known to act as one regulator of the ARP2/3-regulating complex WAVE-HSPC300. As an HSPC300 homolog is present in the Arabidopsis genome but no WAVE homolog has yet been found, the existence of a related regulation pathway was doubtful. Our finding that GRL encodes a putative regulator of the WAVE-HSPC300 complex, NAP125, combined with the phenotypic similarity between arp2/3 and grl mutants, provides evidence that the ARP2/3 complex is indeed regulated by the above mentioned pathway in Arabidopsis.

[General AL-amyloidosis: a rare complication in Waldenstrom macroglobulinemia]

Waldenström's macroglobulinemia (W.M.) is a paraproteinemic disorder similar to multiple myeloma expressing a monoclonal IgM paraprotein. The course of W.M. is milder and the occurrence of renal disease is less frequent than in multiple myeloma. Amyloidosis occurs in less than 5% of patients with monoclonal IgM. We report a 65 year old patient with an asymptomatic long-term survival whose W.M. remained without any therapy. Amyloidosis developed twenty-one years after the initial diagnosis presenting with the nephrotic syndrome, renal and heart failure. W.M. combined with amyloidosis is a rare association. The deposition of amyloid causes progressive organ damage and indicates a bad prognosis. Most commonly nephrotic syndrome or heart failure are signs of amyloidosis. The development of amyloidosis does not seem to be influenced by the duration of W.M. disease or the paraprotein level. It is not known whether the amyloidosis can be prevented by an early chemotherapy.

Early functional apoptotic responses of thymocytes induced by Tri-n-butyltin

BACKGROUND

Programmed cell death, also termed apoptosis, is the main focus of interest in a variety of scientific and clinical areas. For a better understanding of the mechanisms of apoptosis, from the onset of the cellular death program to the late stages of apoptosis or apoptotic necrosis, very early functional events have to be quantified because they might be involved in temporal and causal relationships between apoptosis-related key processes.

METHODS

We have established a flow cytometric technique to quantify time-dependent signals simultaneously with high temporal resolution (Deltat = 1 s) in living cells. With this technique, the response of cells to apoptosis-stimulating agents can be analyzed over 15 min. For this purpose, a thermostatted sample tube holder for repeatable interruption-free injection of substances into the cell suspension was developed. Early detectable fluorescence and scatter parameters were related to intracellular free Ca2+ concentration, [Ca2+]i (Indo-1 fluorometry), membrane permeability (propidium iodide [PI] influx), and cell volume (forward scatter).

RESULTS

A T-cell line (Jurkat) served as a model system. Apoptosis was induced by the biozid Tri-n-butyltin (TBT). Dependent on the TBT concentration (0.3-10 microM), the mean free [Ca2+]i increased by a factor of 1.2-6 during a short time interval of just 2 min. Especially after low TBT concentrations (< 0.5 microM), this [Ca2+]i increase was nearly transient during the observation time of 15 min. Higher TBT concentrations (0.5-10 microM), however, induced a transient increase of [Ca2+]i (Ca-TR) only in a fraction of the cells; in another subpopulation, a steady-state Ca2+ signal (Ca-SST) was observed. The analysis of the simultaneously registered PI signals of the Ca-SST cells showed a shift to increasing PI fluorescence (by a factor of about 4) with increasing Ca2+ concentrations. In Ca-TR cells, the PI fluorescence remained nearly unchanged. These apoptosis-related changes (increase in [Ca(2+)]i and membrane permeability) could be confirmed by the additional observation of a TBT concentration-dependent decrease in cell volume measured during the same early time period.

CONCLUSIONS

The simultaneously analyzed parameters (i.e., [Ca2+]i, membrane permeability, and cell volume) suggested that, in our model system of Jurkat T-cells treated with TBT, an apoptotic cell fate was indicated very early (within 15 min) by the steady-state [Ca2+]i level.

Simultaneous recording of calcium transients and reactive oxygen intermediates of human polymorphonuclear granulocytes in response to formyl-Met-Leu-Phe and the environmental agent sulfite

BACKGROUND

Human polymorphonuclear granulocytes (PMN) are an essential component in the immunological defense network against a variety of harmful pathogens. We have studied the effects of the airborne pollutant sulfite on the calcium metabolism and respiratory burst of these cells simultaneously.

METHODS

A flow cytometric method was developed using the fluochromes Indo-1 and DHR-123. This method allowed us to investigate the real-time kinetics of intracellular free calcium and reactive oxygen intermediates in viable cells with a temporal resolution of 1 s over a time course of 17 min. An additional feature was the possibility to discriminate between reacting and nonreacting cells after treatment with defined stimuli, thus gaining additional insight into the behavior of cell subpopulations.

RESULTS

We analyzed the effects of sulfite on PMN before and after stimulation with formyl-Met-Leu-Phe (FMLP). Treatment with sulfite alone (0.001-1 mM) caused a small, nontransient increase in intracellular calcium. Preincubation with sulfite reduced the maximal calcium response elicited by FMLP. A significant increase in steady-state calcium levels after stimulation with FMLP was observed after treatment with sulfite in concentrations of 10 and 100 mM. Regarding the respiratory burst, treatment with sulfite alone in concentrations of 0.001-1 mM induced a significant increase in DHR-123-derived fluorescence, whereas concentrations of 5 and 10 mM caused a significant depression of this fluorescence below baseline values. Sulfite caused a maximal twofold increase of DHR-123-derived fluorescence compared with the FMLP response. Similar results were obtained after preincubation with sulfite before treatment with FMLP, showing that the effect of sulfite on the respiratory burst was additive to the FMLP response. Regarding the fractions of responding cells, treatment with sulfite up to 1 mM induced a concentration-dependent increase of burst-reactive PMN, whereas preincubation before stimulation with FMLP showed no correlation between sulfite concentration and fraction of burst-reacting cells.

CONCLUSIONS

By simultaneous registration of [Ca(2+)](i) and [H(2)O(2)](i) of PMN after treatment with FMLP and sulfite, the essential responses were already observed within a short time interval (15 min). Striking differences were found in the response of calcium as second messenger and respiratory burst in PMN treated with sulfite. Until a critical concentration (0. 5-1 mM), sulfite caused a concentration-dependent increase of [H(2)O(2)](i), in addition to the FMLP-induced response. The [Ca(2+)](i) changes induced by sulfite alone, however, were found to be small and showed no correlation with the respiratory burst response.

Characterization of dimethyldiacyloxysilanes by differential scanning calorimetry, Raman scattering and X-ray diffraction

The phase behaviour of diacyloxydimethylsilanes (DMS Cn; n = 10, 12, 14, 16, 18, 20, 22) was investigated by differential scanning calorimetry, X-ray diffraction and Raman spectroscopy. All DMS Cn melt from a crystalline phase to an isotropic liquid with a single sharp transition. On cooling, the homologous DMS C16 up to DMS C22 show a characteristic monotropic phase (L beta'H). In contrast to the calorimetrical investigations, it was not possible to analyse the monotropic phase of DMS C16 by X-ray diffraction. This behaviour is due to a two-phase region (gel phase--crystalline phase). The Raman spectra of all DMS are very similar. Only in the low frequency range we find different bands of the longitudinal acoustic modes. The Raman measurements demonstrate undoubtedly that in the solid state the alkyl chains are in all-trans conformation. The factor group splitting of the CH2 scissoring Raman mode show that the DMS Cn are arranged in a subcell packing with two molecules per unit cell. The highly ordered all-trans structure of the alkyl chains is present up to the melting transition. On melting there are changes in different regions of the Raman spectra: C-H stretching, CH2 scissoring mode, C-C skeletal stretching, CH3 rocking and longitudinal acoustic modes. On cooling DMS C18 and DMS C20 from the melt to the crystalline state, the gel phase is also proved by Raman scattering. Based on the results of the Raman and X-ray data the gel phase is characterized by a hexagonal subcell packing and by an ordered structure of the alkyl chain residues.

Differential response of non-transferrin bound iron uptake in rat liver cells on long-term and short-term treatment with iron

BACKGROUND

Uptake of non-transferrin-bound iron by the liver is important as a clearance mechanism in iron overload. In contrast to physiological uptake via receptor-mediated endocytosis of transferrin, no regulatory mechanisms for this process are known. This study compares the influence of long-term and short-term depletion and loading of hepatocytes with iron on the uptake of non-transferrin bound iron, its affinity, specificity and the interaction with the transferrin-mediated pathways.

METHODS

Rats were fed iron-deficient, normal and 3,5,5-trimethylhexanoyl-ferrocene-containing diets to obtain livers with the corresponding desired status and the hepatocytes from these livers were used for transport studies. Hepatocytes from normal rats were depleted or loaded with iron by short-term treatment with desferrioxamine or ferric ammonium citrate, respectively. Uptake of non-transferrin bound iron was assayed from ferric citrate and from ferric diethylene triammine pentaacetate.

RESULTS

Uptake of non-transferrin-bound iron in hepatocytes could be seen as consisting of a high-affinity (Km=600 nM) and a low-affinity component. Whereas in normal and in iron-starved rats the high-affinity component was more prominent, it disappeared altogether in hepatocytes from rats with iron overload resulting from prolonged feeding with TMH-ferrocene-enriched diet. Overloading also led to loss of inhibition by diferric transferrin, which occured in starved as well as normal cells. In contrast, short-term iron-depletion of isolated hepatocytes with desferrioxamine had only a weak stimulatory effect, whereas treatment with ferric ammonium citrate strongly increased the uptake rates. However, the inhibition by diferric transferrin also disappeared. In both cases, uptake of non-transferrin bound iron was inhibited by apotransferrin.

CONCLUSIONS

Non-transferrin bound iron uptake in liver cells is apparently regulated by the iron status of the liver. The mode of response to iron loading depends on the method of loading in terms of time course and the form of iron used. It cannot be explained by the behavior of the iron regulatory protein, and it is complex, seeming to involve more than one transport system.

Isolation of ethyl methanesulfonate-induced gametophytic mutants in Arabidopsis thaliana by a segregation distortion assay using the multimarker chromosome 1

The life cycle of plants comprises two alternating generations, the diploid sporophyte (spore-bearing plant) and the haploid gametophyte (gamete-bearing plant). In contrast to animals, the postmeiotic cells give rise to haploid organisms whose function is to produce the gametes and to mediate fertilization. Analysis of gametophyte development and function has been hampered by the difficulty of identifying haplo-phase-specific mutants in conventional mutagenesis screens. Here we use a genetic strategy that is based on segregation distortion of nearby visible markers to screen for EMS-induced gametophytic mutants in Arabidopsis thaliana. Using the multiple marker chromosome mm1 we have isolated seven lines that displayed an altered segregation of markers. Reciprocal backcrosses of these lines showed a marked reduction of the transmission of the male and/or female gametes. Phenotypic analysis revealed that different aspects of either gametophytic development or function were affected. Three male gametophytic lines showed specific arrests during pollen development. One male gametophytic line was specifically defective in pollen tube elongation. Three gametophytic lines showed variable defects in both male and female gametophytic development.

Physicochemical characterisation of human stratum corneum lipid liposomes

Liposomes were prepared from an extract of all human stratum corneum lipids (hSCL) and characterised in terms of temperature and the presence of Ca2+ by different physicochemical methods. Vesicle aggregation and lateral phase separation were induced by divalent cations with Ca2+ being more efficient than Mg2+. At 24.1 degrees C, i.e. well below physiological temperatures the suspensions consisted of a lamellar phase and crystalline cholesterol. At and above 37 degrees C, this cholesterol surplus was dissolved in the hSCL membranes. However, melting of the hSCL was not completed up to 60 degrees C. The presence of Ca2+ (> or = 9 mM) induced lateral phase separation and fusion of vesicles into extended multilamellar lipid sheets (MLLS) at and above 32.5 degrees C. Upon a subsequent cooling cycle recrystallisation of cholesterol occurred within the MLLS. Finally, membrane mixing of hSCL liposomes with vesicles made of synthetic lipids was investigated. No mixing was observed between either of DPPE/oleic acid, DPPC/DPPE, DPPC/lyso-PC and hSCL liposomes. Mixtures of DPPC/cholesterol hemisuccinate showed a temperature-dependent membrane mixing behaviour, whilst hSCL liposomes and phosphatidylserine liposomes fused temperature-independently with hSCL liposomes.

A combined calorimetric and semiempirical quantum chemical approach to describe the solution thermodynamics of drugs

A combined calorimetric-semiempirical quantum chemical approach is presented to calculate the energy changes for the solution process of drugs. The aim of the presented approach is to understand the elementary steps of the solution process and to propose strategies for an improvement of solubility of drugs. On the basis of the Hess theorem, an alternative route for the solution process via sublimation of the solute, creation of a cavity for the solute in the solvent, transfer into this cavity, and the reorganization of the dipoles of the solute and the solvent can be taken. This approach allows the calculation of all energies describing the direct solution process as well as the alternative route. The approach was tested on 11 substances of different molecular structure by calculating the standard free energy of the specific phase transition. A general way to calculate the energy changes of all phase transitions is given. The complete cycle with DeltaG, DeltaH, and DeltaS was calculated exemplary for the nonsteroidal analgesic ibuprofen. The low solubility of ibuprofen was shown to be due to its high standard free energy of sublimation. Therefore the preparation of solid dispersions could be considered.

Determination of the optimum mixing time for a mixture of lactose and colloidal silicon dioxide

The homogeneity of a mixture of colloidal silicon dioxide (CSD) and lactose is examined by quantifying the dependence of the CSD content on the mixing time. CSD concentration is determined photometrically as a blue silica-molybdic complex. Its deviation from the expected content is taken to characterize the mixture quality and the optimum mixing time. The conformity of this result with the flow properties of the same mixture is studied by measuring the dependence of the angle of repose on the mixing time.

The STUD gene is required for male-specific cytokinesis after telophase II of meiosis in Arabidopsis thaliana

During male meiosis in wild-type Arabidopsis the pollen mother cell (PMC) undergoes two meiotic nuclear divisions in the absence of cell division. Only after telophase II is a wall formed which partitions the PMC into four microspores. Each microspore undergoes two subsequent mitotic divisions to produce one vegetative cell and two sperm cells in the mature pollen grain. In this paper we describe the isolation and the phenotypic characterization of mutations in the STUD (STD) gene, which is specifically required for male-specific cytokinesis after telophase II of meiosis. Although the male meiotic nuclear divisions are normal in std mutant plants, no walls are formed resulting in a tetranucleate microspore. Despite the absence of cell division in the PMC, postmeiotic development in the coenocytic microspore proceeds relatively normally, resulting in the formation of large pollen grains which contain four vegetative nuclei and up to eight sperm cells. Interestingly, these enlarged pollen grains which contain multiple vegetative nuclei and extra sperm cells behave as single male gametophytes, producing only single pollen tubes and resulting in partial male fertility in std mutant plants. Characterization of the process of pollen development and pollen function in std mutants thus reveals two different types of developmental regulation. Each of the four nuclei found in a std microspore following meiosis is capable of independently undergoing the complete mitotic cell division (including cytokinesis) which the single nucleus of a wild-type microspore would normally undertake. The ability of the four meiotic products to independently continue through mitosis does not depend on their division into separate cells, but is controlled by some subcellular component found within the coenocytic microspore. By contrast, the mature std pollen grain functions as a unit and produces only a single pollen tube despite the presence of multiple nuclei within the vegetative cell, suggesting that this process is controlled at the cellular level independently of the extra subcellular components.

Ethane exhalation and vitamin E/ubiquinol status as markers of lipid peroxidation in ferrocene iron-loaded rats

Organ damage caused by iron overload has been mostly attributed to iron-induced peroxidation of membrane lipids. Using the ferrocene iron-loaded rat model, we studied ethane exhalation as a direct marker of in vivo lipid peroxidation, as well as concentrations of alpha-tocopherol and ubiquinol 9/10 in liver and plasma as indirect markers of this process. The feeding of a diet enriched with 0.5% TMH-ferrocene up to 31 weeks resulted in a large increase in liver iron concentration to about 25 mg/g wet weight (w wt). At lower, predominantly hepatocellular liver siderosis, the breath ethane exhalation was dependent on dietary vitamin E (VitE) supplements (onset of ethane exhalation at liver-Fe > 2 mg/g w wt on vitE-restricted diet; > 5 mg Fe per gram on VitE-replete diet). At severe liver siderosis, breath ethane exhalation reached a maximum of approximately 8 nmol/kg/hr independent of VitE supplementation. Plasma as well as hepatic alpha-tocopherol decreased with progressive iron loading. In addition, a significant depletion in hepatic ubiquinol 9 and 10 was noted.

[Health policy goals in child and adolescent health reporting--evaluation with reference to an intermediate-term evaluation]

As a result of the first report on the health of children in Hamburg (1990) 14 primary health policy objectives were identified and related to specific intervention fields. The health information system group at Hamburg has prepared an interim evaluative statement for 1994 on whether and how far each objective has been achieved compared to the targets formulated for the years 1995 and 2000 respectively. 8 out of 14 objectives are considered remaining unchanged as before (i.e. unintentional conception), either proceeding towards the target (i.e. low birth weight, dental health) or having reached the target for 1995 (i.e. infant mortality, age-appropriate vaccination). With 4 objectives the trend deteriorated (i.e. body weight of teenagers, accidents). One objective was monitored on the basis of a new data source (violence against children) and for one objective information could not be proved or updated (breast feeding). In traditional areas of local health policy (i.e. dental health, infant mortality) the health information system and the health targets may be sufficient to help improve the health of the city. In non-lobbied fields (i.e. breast feeding) or those without a consensus on responsibilities (i.e. violence, health and social discrimination) health reports on their own do not invoke achievements, but need to be supported by additional measures.