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1.
Opt Express ; 24(15): 17041-9, 2016 Jul 25.
Article in English | MEDLINE | ID: mdl-27464155

ABSTRACT

We present the design simulation and characterization of a quantum cascade detector operating at 4.3µm wavelength. Array integration and packaging processes were investigated. The device operates in the 4.3µm CO2 absorption region and consists of 64 pixels. The detector is designed fully compatible to standard processing and material growth methods for scalability to large pixel counts. The detector design is optimized for a high device resistance at elevated temperatures. A QCD simulation model was enhanced for resistance and responsivity optimization. The substrate illuminated pixels utilize a two dimensional Au diffraction grating to couple the light to the active region. A single pixel responsivity of 16mA/W at room temperature with a specific detectivity D* of 5⋅107 cmHz/W was measured.

2.
Gesundheitswesen ; 78(3): e6-13, 2016 Mar.
Article in German | MEDLINE | ID: mdl-25531157

ABSTRACT

OBJECTIVE: The aim of this study is to present data concerning children's participation in the German preventive medical examinations for children ("U2" to "U8") in accordance with sections 26 and 92 of the German Social Code (Book V) as retrospectively recorded by the Public Health Service ("Öffentlicher Gesundheitsdienst") of the German Province of Saxony-Anhalt during school entry medical examinations. Also we wanted to analyse the additional variables recorded per child in the areas of social factors, diagnostic findings and levels of therapeutic care in connection with their degree of participation in the preventive medical examinations. METHODOLOGY: The statistical analysis of 73 628 anonymised data sets from the health monitoring system of the German Province of Saxony-Anhalt that were collected by the 14 health authorities in Saxony-Anhalt during school entry medical examinations between 2008 and 2012. An analysis of the data for 20 variables per child was performed with regard to the influence of their degree of participation in the U2 to U8 medical examinations using differences in frequency in the examination groups and checking the significance of these differences by means of the chi-squared test. RESULTS: 99-96% of children in Saxony-Anhalt underwent the 5 preventive medical examinations U2-U6. As the children get older, the participation rates decrease (U2=98.7% down to U8=88.5%). By the time the school entry medical examinations are carried out (at an average age of 63 months), 83% of the children have -undergone all 7 preventive medical examinations for children, while 0.4% have not -undergone one single "U" examination. A child's gender has no influence on its parents' decision as to whether or not it should undergo the examinations. The results also reveal that children who attend day care -facilities are significantly more likely to have undergone all of the U examinations (84.8%) than children who are cared for at home (55.1%). CONCLUSION: The retrospective comprehensive collection of data concerning the children's degree of participation in preventive medical examinations using the school entry medical examination is suitable for identifying connections between participation rates and the social factors, diagnostic findings and levels of therapeutic care of the children in question.


Subject(s)
Diagnostic Tests, Routine/statistics & numerical data , Mass Screening/statistics & numerical data , Patient Participation/statistics & numerical data , Preventive Health Services/statistics & numerical data , School Admission Criteria , Students/statistics & numerical data , Child , Child Day Care Centers/statistics & numerical data , Child Health/statistics & numerical data , Child, Preschool , Female , Germany/epidemiology , Humans , Male , Parents , School Health Services/statistics & numerical data , Sex Distribution , Socioeconomic Factors
3.
Article in English | MEDLINE | ID: mdl-24170086

ABSTRACT

The German Standing Committee on Vaccination (Ständige Impfkommission, STIKO) recommends vaccinating risk groups against hepatitis B and gives advice for postexposure prophylaxis. STIKO has recently revised this recommendation, focusing on: (i) classification of risk groups, (ii) duration of protection after primary immunization, and (iii) anti-HBs threshold that defines successful hepatitis B vaccination. Orientating literature reviews were performed for the first objective. Examples of population subgroups at increased risk were identified and classified into three indication groups. Systematic reviews on the duration of vaccine-induced protection identified one randomized controlled trial (RCT) and nine cohort studies. When applying the grading of recommendation, assessment, development, and evaluation (GRADE) methodology, evidence from RCTs was considered of very low quality regarding the question of whether hepatitis B can be prevented for 15 years after successful primary vaccination (anti-HBs ≥ 10 IU/l) with a vaccine efficacy of 96 % against chronic hepatitis, 89 % against HBsAg positivity, and 73 % against isolated anti-HBc positivity. However, seven cohort studies showed that no cases of clinical hepatitis B or HBsAg positivity occurred during a maximum follow-up period of 10 years in settings comparable to the situation in Germany when anti-HBs ≥ 10 IU/l was used to indicate vaccination success. Less than 1 % of vaccinated study participants had isolated anti-HBc positivity. GRADE assessment of two cohort studies revealed that evidence of very low quality exists that the use of anti-HBs ≥ 100 IU/l to measure vaccination success leads to a lower frequency of anti-HBc positivity during follow-up than the use of anti-HBs ≥ 10 IU/l. The recommendation was revised according to this evidence.


Subject(s)
Evidence-Based Medicine , Hepatitis B Vaccines/standards , Hepatitis B Vaccines/therapeutic use , Hepatitis B/prevention & control , Post-Exposure Prophylaxis/standards , Vaccination/standards , Humans , Treatment Outcome
4.
Article in English | MEDLINE | ID: mdl-23807405

ABSTRACT

Two rotavirus (RV) vaccines were introduced to the European market in 2006. To support the decision-making process of the German Standing Committee on Vaccination ("Ständige Impfkommission", STIKO) regarding adoption of routine RV vaccination into the national vaccination schedule in Germany relevant scientific background was reviewed. According to STIKO's Standard Operating Procedures for the development of evidence-based vaccination recommendations, a set of key questions was addressed and systematic reviews were performed with a focus on the efficacy, effectiveness, impact and safety of RV vaccines. The Grading of Recommendations Assessment, Development and Evaluation (GRADE) methodology was applied to assess the quality of available evidence. Data from 5 randomized controlled trials demonstrated a high efficacy of RV vaccines in preventing severe RV-associated gastroenteritis (91%) and hospitalization (92%) in settings comparable to Germany. Post-marketing observational studies confirmed these findings. In several countries, impact studies suggest that age groups not eligible for vaccination might also benefit from herd effects and demonstrated a decrease in the number of nosocomial RV infections after RV vaccine introduction. The vaccines were considered safe, except for a slightly increased risk of intussusception shortly after the first dose, corresponding to 1-2 additional cases per 100,000 infants vaccinated (relative risk =1.21, 95% confidence interval [CI] 0.68-2.14). RV case-fatality is extremely low in Germany. However, RV incidence among children aged <5 years is high (reported 8-14 cases per 1000 children annually), and of these almost half require hositalization. In view of the available evidence and expected benefits, STIKO recommends routine rotavirus vaccination of children under the age of 6 months with the main goal of preventing RV-associated hospitalizations in Germany, especially among infants and young children.


Subject(s)
Mass Vaccination/standards , Practice Guidelines as Topic , Rotavirus Infections/prevention & control , Rotavirus Vaccines/standards , Rotavirus Vaccines/therapeutic use , Female , Germany , Humans , Infant , Infant, Newborn , Male
5.
Sens Actuators A Phys ; 188: 167-172, 2012 Dec.
Article in English | MEDLINE | ID: mdl-23288983

ABSTRACT

The encapsulation and packaging reliability in fully integrated, fully wireless 100 channel Utah Slant Electrode Array (USEA)/integrated neural interface-recording version 5 (INI-R5) has been evaluated by monitoring the extended long term in-vitro functional stability and recording longevity. The INI encapsulated with 6-µm Parylene-C was immersed in phosphate buffer saline (PBS) at room temperature for a period of over 12 months. The USEA/INI-R5, while being soaked was powered and configured wirelessly through 2.765 MHz inductive link and the transmitted frequency shift keying (FSK) modulated radio-frequency (RF) (900 MHz Industrial, scientific, medical-ISM band) signal was also recorded wirelessly as a function of soak time. In order to test the long term recording ability, in-vitro wireless recording was performed in agarose for few channels. The full functionality and the ability of the electrodes to record artificial neural signals even after 12 months of PBS soak provides a measure of encapsulation reliability, the functional and recording stability in fully integrated wireless neural interface and potential usefulness for future chronic implants.

6.
Clin Exp Allergy ; 40(2): 289-98, 2010 Feb.
Article in English | MEDLINE | ID: mdl-20210807

ABSTRACT

BACKGROUND: At the time of the German reunification in 1990, manifestations of most allergic diseases were less prevalent in East than in West Germany. It was hypothesized that these East-West differences would diminish with lifestyle and pollution changes in East Germany. OBJECTIVE: To investigate whether changes in the prevalence of asthma, hayfever, eczema or allergic sensitization in East Germany approached the levels seen in West Germany and to identify possible lifestyle or environmental factors that may influence this. METHODS: Between 1991 and 2000, 6-year-old children from four areas in East Germany participated in an annual survey. Every 3rd year, a parallel survey was performed in four areas of West Germany. In total, 31 903 children were included. Parents completed a questionnaire regarding lifestyle factors and diagnoses and symptoms of asthma, hayfever and eczema. In sub-areas, eczema was clinically assessed by a dermatologist. Specific IgE sensitization was determined for 6121 children. Logistic regression was used to analyse differences in time trends and the influence of lifestyle and pollution changes. RESULTS: Lifestyle and pollution changed significantly differently between East and West Germany. The trends in hayfever and in strong (specific IgE >3.5) sensitization against pollen, and particularly birch pollen, were steeper in East than in West Germany. The trend towards marked pollen sensitization was four times stronger (95% confidence interval 1.2-13.9) in East than in West Germany. Increasing numbers of only children, less single-room heating with fossil fuels and increasing importance of traffic-related pollution in East Germany partly explained these differences in time trends. CONCLUSIONS: Hayfever and sensitization against pollen were the most sensitive allergic manifestations to changes experienced specifically in East Germany. Influences of lifestyle (single-room heating, living as a single child) were important in explaining different trend developments.


Subject(s)
Hypersensitivity/epidemiology , Asthma/diagnosis , Asthma/epidemiology , Child , Eczema/diagnosis , Eczema/epidemiology , Environmental Pollution/analysis , Female , Germany, East/epidemiology , Germany, West/epidemiology , Humans , Hypersensitivity/diagnosis , Immunoglobulin E/analysis , Life Style , Logistic Models , Male , Only Child/statistics & numerical data , Pollen/immunology , Predictive Value of Tests , Reproducibility of Results , Rhinitis, Allergic, Seasonal/diagnosis , Rhinitis, Allergic, Seasonal/epidemiology , Sensitivity and Specificity , Sex Characteristics , Surveys and Questionnaires
7.
Biomed Microdevices ; 11(2): 453-66, 2009 Apr.
Article in English | MEDLINE | ID: mdl-19067174

ABSTRACT

This report presents results from research towards a fully integrated, wireless neural interface consisting of a 100-channel microelectrode array, a custom-designed signal processing and telemetry IC, an inductive power receiving coil, and SMD capacitors. An integration concept for such a device was developed, and the materials and methods used to implement this concept were investigated. We developed a multi-level hybrid assembly process that used the Utah Electrode Array (UEA) as a circuit board. The signal processing IC was flip-chip bonded to the UEA using Au/Sn reflow soldering, and included amplifiers for up to 100 channels, signal processing units, an RF transmitter, and a power receiving and clock recovery module. An under bump metallization (UBM) using potentially biocompatible materials was developed and optimized, which consisted of a sputter deposited Ti/Pt/Au thin film stack with layer thicknesses of 50/150/150 nm, respectively. After flip-chip bonding, an underfiller was applied between the IC and the UEA to improve mechanical stability and prevent fluid ingress in in vivo conditions. A planar power receiving coil fabricated by patterning electroplated gold films on polyimide substrates was connected to the IC by using a custom metallized ceramic spacer and SnCu reflow soldering. The SnCu soldering was also used to assemble SMD capacitors on the UEA. The mechanical properties and stability of the optimized interconnections between the UEA and the IC and SMD components were measured. Measurements included the tape tests to evaluate UBM adhesion, shear testing between the Au/Sn solder bumps and the substrate, and accelerated lifetime testing of the long-term stability for the underfiller material coated with a a-SiC(x):H by PECVD, which was intended as a device encapsulation layer. The materials and processes used to generate the integrated neural interface device were found to yield a robust and reliable integrated package.


Subject(s)
Electrodes, Implanted , Electrophysiology/instrumentation , Microelectrodes , Signal Processing, Computer-Assisted/instrumentation , Telemetry/instrumentation , Equipment Design , Equipment Failure Analysis , Reproducibility of Results , Sensitivity and Specificity , Systems Integration , Telemetry/methods
8.
Gesundheitswesen ; 71(10): 675-9, 2009 Oct.
Article in German | MEDLINE | ID: mdl-19885769

ABSTRACT

INTRODUCTION: On May 3, 2009, a first case of influenza A/H1N1 infection occurred in the federal state of Saxony-Anhalt, Germany. In order to stop the possible spread of the virus and to study the epidemiological and clinical characteristics of the infection, an investigation was launched by the local health authorities and the RKI. METHODS: Standardised questionnaires were used to assess demographic and clinical data. Specimens were collected from case patients and close contacts and were analysed for influenza A/H1N1 using real-time PCR. RESULTS: The index patient showed fever and coughing 3.5 days after returning from a holiday in Mexico. The local health authorities were informed on May 3, and measures were rapidly implemented. These measures included a trace-back of possible contact persons, isolation of the case and close contacts, prophylactic treatment with Oseltamivir. Virological investigations showed that the case shedded viral genome up until the last day of antiviral therapy. Viral genome was also detected in the spouse and the son of the patient. Both showed no symptoms under a prophylactic treatment with antiviral medication. No viral genome was detected in three other family members, and in six other contact persons outside of the family. DISCUSSION: The spread of the virus was contained due to the fast response of the local health authorities. Two secondary cases occurred in the family. These cases remained asymptomatic, possibly due to antiviral prophylaxis. Epidemiological and virological results suggest that the influenza A/H1N1 virus has a longer incubation period and that viral shedding may probably be prolonged when compared with seasonal influenza.


Subject(s)
Disease Outbreaks/prevention & control , Family Health , Influenza A Virus, H1N1 Subtype , Influenza, Human/epidemiology , Influenza, Human/transmission , Risk Assessment/methods , Travel/statistics & numerical data , Adolescent , Adult , Cluster Analysis , Disease Outbreaks/statistics & numerical data , Female , Germany/epidemiology , Humans , Incidence , Influenza, Human/genetics , Influenza, Human/virology , Male , Mexico , Middle Aged , Population Surveillance , Risk Factors , Young Adult
9.
Article in German | MEDLINE | ID: mdl-19768390

ABSTRACT

Vaccination registries are databases intended to assess and manage complete vaccination data of as many individuals as possible in a population under survey. The task of these registries is to identify low vaccination rates on the individual and population level, to enable systems of reminding individuals, to focus vaccination campaigns and to maximize overall vaccination coverage. Saxony-Anhalt is the only federal state of Germany to have a law that prescribes the reporting of vaccinations. Vaccinations of children up to the age of 7 are reported to the regional public health services. However, as the law provides no regulations as to how the data should be registered and processed, the development of a vaccination registry depends entirely on the initiative and cooperation of the "players in vaccination". The key players in vaccination in Saxony-Anhalt have recently created a Vaccination-Committee, which set out to develop the theoretical standards and a software prototype for the establishment of a computerized vaccination registry. Recent developments in the public health reporting system of Saxony-Anhalt (which strives to modernize its computerized assessment of child and adolescent health) are now opening the possibility to integrate the vaccination registry into the commercially available child health software.


Subject(s)
Mandatory Reporting , Mass Vaccination/legislation & jurisprudence , Medical Records Systems, Computerized/legislation & jurisprudence , Registries/standards , Germany
10.
Int Arch Allergy Immunol ; 143(4): 282-9, 2007.
Article in English | MEDLINE | ID: mdl-17351327

ABSTRACT

BACKGROUND: Early childhood influences are important for the development of the allergic phenotype. In East Germany, tremendous lifestyle changes took place after 1990 and it can be hypothesized that the allergic phenotypes in mothers and their children are less similar than in West Germany. This was investigated in our study done in mothers and their 6-year-old children from East and West Germany in the year 2000. METHODS: 1,393 mother-child pairs participated. A subgroup of 774 pairs gave blood for the determination of specific IgE. Regional differences in mother-child correlations and in prevalence of mother-child combinations with respect to allergic sensitization and disease were examined by logistic regression analysis. RESULTS: The adjusted association in positive allergic sensitization between mothers and their children was not significant in East Germany (OR 1.23, 95% CI: 0.68-2.24) but highly significant in West Germany (OR 2.89, 95% CI: 1.73-4.80). The probability for the combination of 'negative' mother and 'positive' child was significantly higher in East than in West Germany. CONCLUSIONS: Mother-child transmission of atopy predisposition can even be cancelled by environmental changes.


Subject(s)
Allergens/immunology , Hypersensitivity/epidemiology , Hypersensitivity/immunology , Mothers , Adult , Age Factors , Allergens/adverse effects , Child , Child, Preschool , Female , Genetic Predisposition to Disease , Germany/epidemiology , Germany, East/epidemiology , Germany, West/epidemiology , Humans , Hypersensitivity/genetics , Male , Prevalence
11.
Mol Cell Biol ; 4(7): 1260-9, 1984 Jul.
Article in English | MEDLINE | ID: mdl-6095056

ABSTRACT

To assess the factors required for integration and expression of retroviral DNA, we have examined viral DNA, RNA, and protein in NIH/3T3 mouse cells transformed by transfection with various forms of cloned Rous sarcoma virus (RSV) DNA. Linear RSV DNA molecules, derived from circular DNA containing two long terminal repeats (LTRs) and permuted by cleavage at the SacI restriction endonuclease site in the leader sequence, were integrated near the ends of the linear molecule, with the LTRs on the 3' side of the src gene. Integration of a subgenomic RSV DNA fragment containing the viral src gene without intact LTRs also occurred near the ends of the linear molecule. Head-to-tail tandem arrays of RSV DNA species were observed in some transformed cell lines that received fully digested DNA and in all cell lines that received DNA ligated to produce oligomers before transfection. Closed circular RSV DNA, with one or two LTRs, integrated without apparent specificity within several regions of the viral genome. After transfection with SacI-permuted RSV DNA still linked to arms of the lambda bacteriophage vector DNA, bacteriophage sequences were joined to host DNA. Transformed cell lines produced by transfection with the various forms of RSV DNA produced similar levels of viral src protein, although the efficiency of successful transformation varied by at least two orders of magnitude. Analyses of viral polyadenylated RNA, together with the patterns of viral DNA in transformed cells, indicated that viral DNA can be integrated and expressed without regard to LTR sequences, with adjacent host DNA presumably supplying signals required for the promotion and processing of functional src mRNA.


Subject(s)
Avian Sarcoma Viruses/genetics , DNA, Viral/genetics , Genes, Viral , Genes , Transfection , Animals , Cells, Cultured , Chimera , DNA/analysis , Mice , Mice, Inbred Strains , Viral Proteins/genetics
12.
Gesundheitswesen ; 69(4): 256-62, 2007 Apr.
Article in German | MEDLINE | ID: mdl-17533569

ABSTRACT

On October 5th, 2006, the German Reference Centre for Meningococci (NRZM) held the 3rd Workshop on Epidemiology, Prevention and Treatment of Invasive Meningococcal Disease, in collaboration with the German Society for Hygiene and Microbiology (DGHM). Given the recent recommendation of the German Standing Committee on Vaccination (STIKO) for conjugate meningococcal C vaccination of all children in the second year of life, observations from meningococcal C conjugate vaccination campaigns in other European countries were presented and compared to the German situation. Moreover, the newly implemented cluster detection routines employed at the NRZM and their integration into the interactive geographical information system EpiScanGIS were shown. Based on recent experiences from regional outbreaks in Oberallgäu, Sangerhausen, and Greater Aachen, examples for public health intervention were given at the conference. In addition, current developments in the area of meningococcal research, as well as trends in antimicrobial susceptibility were covered. Finally, the latest evidence concerning the clinical management and chemoprophylaxis of this invasive bacterial disease was discussed.


Subject(s)
Biomedical Research/trends , Disease Outbreaks/prevention & control , Meningococcal Infections/epidemiology , Meningococcal Infections/therapy , Population Surveillance/methods , Practice Patterns, Physicians'/trends , Europe/epidemiology , Humans , Meningococcal Infections/diagnosis , Meningococcal Infections/prevention & control
13.
Gesundheitswesen ; 68(10): 633-7, 2006 Oct.
Article in German | MEDLINE | ID: mdl-17099824

ABSTRACT

From August 2004 to January 2005 a cluster of 7 cases of serogroup B meningococcal disease occurred in the state of Saxony-Anhalt in the town of Sangerhausen and the surrounding area. This led to an investigation of meningococcal carriage in 816 high school students (grades 9 to 13). The students were also asked to fill out a questionnaire regarding possible risk factors for carriage. The goal of the study was the evaluation of a possibly persistently increased risk for further cases in the region. Results of the study were to be used for a comprehensive and targeted education of the public. The percentage of students found harbouring N. meningitidis in the nasopharynx in Sangerhausen (9.0 %) was not elevated compared to that found in the two control regions of Kelbra, County of Sangerhausen (8.2 %) and Jessen, County of Wittenberg (9.9 %). The serogroup B fine type responsible for the cluster (P1.7-2,16:F3-3:PorB3-24) was found only in one student each in Sangerhausen and Kelbra. Thus, there was no evidence of an increased risk for further cases at the time of the study at the end of January, 2005. This may have been due to intensive contact tracing and provision of chemoprophylaxis in Sangerhausen. Visiting a disco or bar and smoking were identified as risk factors for meningococcal carriage. However, these factors were associated with carriage only in boys but not in girls. This may be explained by sex-specific differences in physical interaction with others. Efforts to prevent further cases during clusters of meningococcal disease should consider sex-specific risk behaviour.


Subject(s)
Carrier State/epidemiology , Disease Outbreaks/statistics & numerical data , Meningitis, Meningococcal/epidemiology , Population Surveillance , Risk Assessment/methods , Students/statistics & numerical data , Adolescent , Adult , Carrier State/diagnosis , Female , Germany/epidemiology , Humans , Incidence , Male , Meningitis, Meningococcal/diagnosis , Risk Factors
14.
Cancer Res ; 55(23 Suppl): 5983s-5989s, 1995 Dec 01.
Article in English | MEDLINE | ID: mdl-7493381

ABSTRACT

Single-chain Fv proteins containing a COOH-terminal cysteine (sFv') were constructed by using an antidigoxin 26.10 sFv and an anti-c-erbB-2 741F8 sFv. The fully active sFv' proteins were prepared by expression in Escherichia coli as insoluble inclusion bodies, followed by in vitro refolding using glutathione redox buffers and purification. The COOH-terminal cysteines of the refolded sFv' proteins were protected by a blocking group presumed to be the glutathionyl peptide, which was easily and selectively removed by gentle reduction. Air oxidation of the reduced sFv' monomers resulted in the efficient formation of disulfide-linked sFv' homodimers, designated (sFv')2, which were stable under oxidizing conditions and relatively slow to be disrupted under reducing conditions. The (26-10-1 sFv')-(741F8-1 sFv') heterodimer was prepared and possessed dual-antigen specificity; the active bispecific (sFv')2 dimerized under native conditions, apparently as a manifestation of self-association by the 741F8 sFv' subunit. Biodistribution and imaging studies that were performed on mice bearing human SK-OV-3 tumor xenografts that express the c-erbB-2 as a cell surface antigen were reviewed. Radioiodinated 741F8-2 (sFv')2 homodimer localized to the tumors with high specificity, as evidenced by excellent tumor:normal tissue ratios. Sagittal section autoradiography of whole animals 24 h after administration of antibody species revealed that 741F8 (sFv')2 produced a stronger tumor image than comparable doses of the 741F8 Fab, monomeric sFv', and the 26-10 (sFv')2 control without the high nonspecific background distribution of the 741F8 IgG.


Subject(s)
Immunoglobulin Fragments , Iodine Radioisotopes , Neoplasms/diagnostic imaging , Receptor, ErbB-2/immunology , Amino Acid Sequence , Animals , Cysteine/chemistry , Cysteine/immunology , Escherichia coli , Humans , Immunoglobulin Fragments/immunology , Immunoglobulin Fragments/metabolism , Mice , Mice, Nude , Molecular Sequence Data , Neoplasms/immunology , Protein Folding , Radionuclide Imaging , Recombinant Proteins/chemistry , Recombinant Proteins/immunology , Tissue Distribution , Transplantation, Heterologous
15.
Cancer Res ; 53(17): 4026-34, 1993 Sep 01.
Article in English | MEDLINE | ID: mdl-7689421

ABSTRACT

The in vivo properties of monovalent and divalent single-chain Fv (sFv)-based molecules with the specificity of the anti-c-erbB-2 monoclonal antibody 741F8 were examined in scid mice bearing SK-OV-3 tumor xenografts. 741F8 sFv monomers exhibited rapid, biphasic clearance from blood, while a slightly slower clearance was observed with the divalent 741F8 (sFv')2 comprising a pair of 741F8 sFv' with a C-terminal Gly4Cys joined by a disulfide bond. Following i.v. injection, the 741F8 sFv monomer was selectively retained in c-erbB-2-overexpressing SK-OV-3 tumor, with excellent tumor:normal organ ratios uniformly exceeding 10:1 by 24 h. The specificity of this effect was demonstrated by the lack of retention of the anti-digoxin 26-10 sFv monomer, as evaluated by biodistribution studies, gamma camera imaging, and cryomacroautoradiography studies. The specificity index (741F8 sFv retention/26-10 sFv retention) of 741F8 monomer binding, measured by the percentage of injected dose per g of tissue, was 13.2:1 for tumor, and 0.8 to 2.1 for all tested normal organs, with specificity indices for tumor:organ ratios ranging from 7.0 (kidneys) to 16.7 (intestines). Comparing divalent 741F8 (sFv')2 with the 26-10 (sFv')2, similar patterns emerged, with specificity indices for retention in tumor of 16.9 for the Gly4Cys-linked (sFv')2. These data demonstrate that, following their i.v. administration, both monovalent and divalent forms of 741F8 sFv are specifically retained by SK-OV-3 tumors. This antigen-specific binding, in conjunction with the 26-10 sFv controls, precludes the possibility that passive diffusion and pooling in the tumor interstitium contributes significantly to long-term tumor localization. 741F8 (sFv')2 species with peptide spacers exhibited divalent binding and increased retention in tumors as compared with 741F8 sFv monomers. Since the blood retention of the (sFv')2 is slightly more prolonged than that of the monomer, it was necessary to demonstrate that the increased tumor localization of the peptide-linked (sFv')2 was due to its divalent nature. The significantly greater localization of the divalent bismalimidohexane-linked 741F8 (sFv')2 as compared with a monovalent 741F8 Fab fragment of approximately the same size suggests that the increased avidity of the (sFv')2 is a factor in its improved tumor retention. This is the first report of successful specific in vivo targeting of tumors by divalent forms of sFv molecules. The improved retention of specific divalent (sFv')2 by tumors may have important consequences for targeted diagnostic or therapeutic strategies.


Subject(s)
Antibodies, Monoclonal/metabolism , Immunoglobulin Fragments/metabolism , Proto-Oncogene Proteins/immunology , Skin Neoplasms/metabolism , Animals , Antibodies, Monoclonal/immunology , Antibodies, Monoclonal/isolation & purification , Antibody Affinity , Antibody Specificity , Autoradiography , Epitopes , Extracellular Space/metabolism , Immunoglobulin Fragments/immunology , Immunoglobulin Fragments/isolation & purification , Mice , Mice, Inbred BALB C , Mice, SCID , Proto-Oncogene Proteins/metabolism , Radionuclide Imaging , Receptor, ErbB-2 , Skin Neoplasms/diagnostic imaging , Tissue Distribution
16.
Biochim Biophys Acta ; 518(3): 401-12, 1978 May 23.
Article in English | MEDLINE | ID: mdl-77683

ABSTRACT

Kethoxal bis(thiosemicarbazone) induces the synthesis of four proteins (100 000, 70 000, 35 000 and 25 000 daltons) in normal chick embryo cells. The 70 000 dalton species is produced at the fastest rate 2 hr after exposure to the compound. Pulse-chase experiments revealed neither precursors nor products of these proteins and both actinomycin and cycloheximide inhibited their synthesis. Neither of the two substituents of the inducer, kethoxal or thiosemicarbazide, were active. The four proteins were induced in several other species, but human cells produced only three proteins (100 000, 70 000 and a different 30 000 dalton form).


Subject(s)
Protein Biosynthesis , Thiosemicarbazones/pharmacology , Animals , Cells, Cultured , Chick Embryo , Cycloheximide/pharmacology , DNA/biosynthesis , DNA Repair , Dactinomycin/pharmacology , Humans , Molecular Weight , Protein Precursors/biosynthesis , Proteins/physiology , Species Specificity
17.
Biochim Biophys Acta ; 606(1): 170-80, 1980.
Article in English | MEDLINE | ID: mdl-7353015

ABSTRACT

Several transition series metals (copper, cadmium, zinc and mercury) and the sulfhydryl reagent, sodium arsenite, enhance the synthesis of specific proteins in chick embryo cells and in human foreskin cells in culture. The proteins are visible 1--3 h after exposure to concentrations ranging from 10 microM to 100 microM depending upon which reagent is used. These proteins comigrate on acrylamide gel electropherograms with the proteins induced by two copper-chelating drugs, kethoxal bis(thiosemicarbazone) and disulfiram, and by heat shock. However, these proteins migrate in a significantly different manner than do the canavanine-enhanced proteins. The four proteins induced in chick embryo cells are distinct from one another as determined by partial proteolytic mapping. Simlarly, the three proteins induced in human cells are distinct. However, the 100-kilodalton and the 70-kilodalton proteins from chick and from human cells appear to be related as judged by this mapping procedure. The 70 kilodalton protein enhanced by kethoxal bis(thiosemicarbazone), disulfiram, arsenite and heat shock have a high degree of similarity according to this technique. The arsenite and canavanine-enhanced 100-kilodalton proteins are related as are the arsenite-enhanced 70-kilodalton and the canavanine-enhanced 75-kilodalton proteins. The canavanine-enhanced 30 kilodalton protein resembles the arsenite-enhanced 25-kilodalton protein rather than the 35-kilodalton species. In view of these findings, it appears that a variety of treatments, namely, chelating drugs, transition series metals, sulfhydryl reagents, heat shock, and amino acid analogous can induced similar, if not identical, proteins in eukaryotic cells.


Subject(s)
Cells/metabolism , Copper/pharmacology , Eukaryotic Cells/metabolism , Protein Biosynthesis , Sulfhydryl Reagents/pharmacology , Animals , Arsenic/pharmacology , Arsenites , Cadmium/pharmacology , Canavanine/pharmacology , Chick Embryo , Fibroblasts/drug effects , Hot Temperature , Humans , Kinetics , Male , Mercury/pharmacology , Molecular Weight , Papain , Proteins/analysis , Sodium Compounds , Zinc/pharmacology
18.
Biochim Biophys Acta ; 519(1): 65-75, 1978 Jun 22.
Article in English | MEDLINE | ID: mdl-78722

ABSTRACT

Antabuse (disulfiram) is widely used in the treatment of chronic alcoholism. We have examined the effect of this drug on malignant transformation by Rous sarcoma virus, on eukaryotic cell synthesis, and on nucleic acid binding. It was found that: (1) Disulfiram inhibits the activity of the RNA dependent DNA polymerase of Rous sarcoma virus and inactivates the ability of the virus to malignantly transform chick embryo cells. The monomer of disulfiram, diethyldithiocarbamate does not affect the virus. (2) Disulfiram induced the synthesis of four proteins in normal chick embryo and human foreskin cells. The monomer diethyldithiocarbamate, induced these proteins also. Cellular DNA synthesis is more sensitive to disulfiram than are RNA and protein synthesis. (3) Disulfiram binds to neither DNA or RNA in the presence or absence of copper. However, diethyldithiocarbamate in the presence of, but not in the absence of, copper binds to HeLa cell DNA and to Rous sarcoma virus 70 S genome RNA. These results indicate that this compound, which causes no symptoms in people who do not consume alcohol, may have significant effects on a cellular level.


Subject(s)
Avian Sarcoma Viruses/drug effects , Cell Transformation, Viral/drug effects , Disulfiram/pharmacology , Animals , Cell Transformation, Neoplastic/drug effects , Cells, Cultured , Chick Embryo , Copper/metabolism , DNA/metabolism , DNA, Viral/metabolism , Ditiocarb/pharmacology , Humans , Protein Biosynthesis , RNA/metabolism , Reverse Transcriptase Inhibitors
19.
Biochim Biophys Acta ; 949(2): 233-9, 1988 Feb 28.
Article in English | MEDLINE | ID: mdl-3277669

ABSTRACT

In this report we describe the expression of v-raf protein in E. coli using a tryptophan-promoter-driven expression vector and its immunological characterization by anti-peptide sera. The purified recombinant protein was used to produce raf-specific antibodies which are suitable for studying v-raf and c-raf proteins in vitro and in vivo in a variety of species ranging from mouse to man.


Subject(s)
Oncogenes , Recombinant Proteins/immunology , Amino Acid Sequence , Antibody Specificity , Chemical Precipitation , Cloning, Molecular , Escherichia coli/genetics , Molecular Weight , Peptide Fragments/immunology , Structure-Activity Relationship
20.
J Mol Biol ; 244(5): 657-8, 1994 Dec 16.
Article in English | MEDLINE | ID: mdl-7990148

ABSTRACT

We have obtained trigonal crystals of recombinant human osteogenic protein-1 (hOP-1), a member of the transforming growth factor-beta (TGF-beta) superfamily. hOP-1 (also referred to as BMP-7) is a bone morphogenetic protein and is active as a dimer of M(r) 32 to 36 kDa. The crystals have the symmetry of space group P3(1)21 or the enantiomorph P3(2)21 with unit cell dimensions of a = b = 99.46 A, c = 42.09 A. The crystals diffract to 2.2 A resolution and there is one hOP-1 monomer per asymmetric unit. In this paper we describe the first crystallization of a bone morphogenetic protein and present the results of preliminary X-ray diffraction data from the native protein and two heavy-atom derivatives.


Subject(s)
Bone Morphogenetic Proteins , Proteins/chemistry , Bone Morphogenetic Protein 7 , Crystallization , Crystallography, X-Ray , Humans , Recombinant Proteins/chemistry , Transforming Growth Factor beta/chemistry
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