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Kroegel C, Foerster M, Grahmann PR, Braun R. Eosinophil priming and migration in idiopathic pulmonary fibrosis. Eur Respir J 1998; 11:999-1001. [PMID: 9648945 DOI: 10.1183/09031936.98.11050999] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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Gabard DL, Porzio R, Oxford T, Braun R. Admission interviews: questions of utility and cost in masters of physical therapy programs in the United States. PHYSIOTHERAPY RESEARCH INTERNATIONAL 1998; 2:135-49. [PMID: 9421819 DOI: 10.1002/pri.96] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
PURPOSE The purpose of this research was twofold. The first purpose was to assess the predictive validity of the interview process in student completion of entry level Masters of Physical Therapy programs on the conventional schedule for the university. The second was to provide a descriptive study of interview formats currently used by these institutions and the cost to the institution, estimated by hours of labor used exclusively for the interview process. METHOD A questionnaire was mailed to the Director of Admissions of 63 accredited Masters of Physical Therapy programs in the United States. Forty-three responded to the questionnaire for a response rate of 68.3%. Twenty-eight programs (65.1%) performed interviews and fifteen (34.9%) programs did not. RESULTS A two-tailed t-test revealed that no significant difference existed between programs that interview and those that did not with regards to the attrition rate of students. There was great diversity between the programs in interview content and structure. The cost to the institutions in terms of hours averaged 261 hours per school for faculty and support staff combined. CONCLUSION The schools of physical therapy that award the Masters of Physical Therapy degree vary markedly in the interview content and format both between schools and with recommendations known to enhance validity and reliability. Since, no difference exists in attrition of students between schools that interview and those that do not, the expense and time invested by both the institution and the students are important considerations. The findings of this study indicate the need for continued investigation of the effectiveness of the interview process and alternative methods of valid and reliable student selection.
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Krischer J, Skaria A, Guillod J, Lemonnier E, Salomon D, Braun R, Saurat JH. Epiluminescent light microscopy of melanocytic lesions after dermoepidermal split. Dermatology 1997; 195:108-11. [PMID: 9310714 DOI: 10.1159/000245710] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
BACKGROUND In vivo epiluminescent light microscopy (ELM) of pigmented skin lesions reveals numerous elementary structures. Among them, the pigment network (PN), black dots (BD) and brown globules (BG) constitute important semiologic features. Based on histological extrapolations, it has been postulated that PN should reflect the presence of melanin in the epidermis and its honeycomb aspect should result from the dermoepidermal architecture. OBJECTIVE To demonstrate this directly by analyzing separately by ELM the epidermal and dermal sides of melanocytic lesions. METHODS We split the epidermis from the dermis of 10 pigmented lesions (6 lentigos, 4 nevocytic nevi) by incubation with dispase. ELM images were done in vivo before excision, then ex vivo on the whole specimen and separately on the split epidermis and dermis. Epidermal and dermal specimens were finally controlled by histology. RESULTS PN was observed only on the epidermal side of the split. Its organization was remarkably conserved after the procedure as compared with prior in vivo images. In contrast, pigmentation observed on dermal sides of the splits showed no organized pattern and corresponded to melanophages. BG were found on the dermal side and BD on the epidermal side of the split lesions, which confirms previous hypotheses. CONCLUSION By subtracting the dermal pigmentation and vessels from the image, the split technique has thus established the epidermal origin of the PN and given a more detailed ELM analysis of network components.
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Fuchs W, Schatzmayr G, Braun R. Nitrate removal from drinking water using a membrane-fixed biofilm reactor. Appl Microbiol Biotechnol 1997; 48:267-74. [PMID: 9299786 DOI: 10.1007/s002530051049] [Citation(s) in RCA: 25] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Biological treatment of drinking water is a cost-effective alternative to conventional physico/chemical processes. A new concept was tested to overcome the main disadvantage of biological denitrification, the intensive post-treatment process to remove microorganisms and remnant carbon source. The biological reaction zone and carbon supply were separated from the raw water stream by a nitrate-permeable membrane. Denitrification takes place in a biofilm, which is immobilized at the membrane. In a series of bench-scale runs, different types of membranes and reactor configurations were investigated. The best denitrification rates achieved were 1230 mg NO3(-)-N m-2 day-1. In one run, raw water containing 100 mg NO3- 1-1 was completely freed from nitrate. The membrane and the attached biofilm also represent a barrier against the passage of the C source and nutrients into the raw water. At concentrations of 20 mg 1-1 ethanol and 15 mg 1-1 phosphate in the bioreactor no diffusion through the membrane into the treated water was observed. Without any post-treatment, the effluent met nearly all the relevant criteria for drinking water; only the colony count was slightly increased.
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Braun R. Book review. Infection 1997. [DOI: 10.1007/bf01713150] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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Abstract
This article reviews the pearls and pitfalls of high-altitude sickness, decompression sickness, and barotrauma; new findings relevant to the near-drowning patient; continued controversies on hyperbaric oxygen for carbon monoxide poisoning; pitfalls in hypothermia management; and updates on the management of venomous snakebites.
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Reichrath J, Seyfried P, Braun R, Müller SM, Baum HP, Bahmer FA. Expression of NM23 protein in acquired melanocytic nevi, malignant melanoma and metastases of malignant melanoma: an immunohistological assessment in human skin. Dermatology 1997; 194:136-9. [PMID: 9094461 DOI: 10.1159/000246082] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
BACKGROUND It has been suggested that nm23 may exert metastasis suppressor function in human tumors. OBJECTIVE We have analyzed expression of nm23 polypeptide in acquired melanocytic nevi (n = 19), dysplastic nevi (n = 19), malignant melanomas (n = 22) and metastases of malignant melanomas (n = 47) in situ. METHODS Nm23 protein was detected immunohistochemically on paraffin sections using the highly sensitive labeled avidin-biotin technique. RESULTS We found that (1) nm23 polypeptide is predominantly expressed in the cytoplasmic but also in nuclear and membrane compartments of melanocytic human cells, (2) expression of nm23 protein does not correlate with benign or malignant phenotype in melanocytic tumors of human skin. CONCLUSION Our study challenges the hypothesis that nm23 may function in malignant melanomas as a tumor suppressor gene.
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Zillmann U, Konstantinov SM, Berger MR, Braun R. Improved performance of the anion-exchange centrifugation technique for studies with human infective African trypanosomes. Acta Trop 1996; 62:183-7. [PMID: 9025986 DOI: 10.1016/s0001-706x(96)00018-6] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
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Vassella E, Roditi I, Braun R. Heterogeneous transcripts of RIME/ingi retroposons in Trypanosoma brucei are unspliced. Mol Biochem Parasitol 1996; 82:131-5. [PMID: 8943159 DOI: 10.1016/0166-6851(96)02726-0] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
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Braun R, Feudel F. Supertransient chaos in the two-dimensional complex Ginzburg-Landau equation. PHYSICAL REVIEW. E, STATISTICAL PHYSICS, PLASMAS, FLUIDS, AND RELATED INTERDISCIPLINARY TOPICS 1996; 53:6562-6565. [PMID: 9965022 DOI: 10.1103/physreve.53.6562] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/12/2023]
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Eschenbacher KH, Eggli P, Wallach M, Braun R. Characterization of a 14 kDa oocyst wall protein of Eimeria tenella and E. acervulina. Parasitology 1996; 112 ( Pt 2):169-76. [PMID: 8851856 DOI: 10.1017/s0031182000084730] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
We have extracted a protein of 14 kDa from purified oocyst walls of several Eimeria species. Polyclonal antibodies were raised in rats against the 14 kDa proteins of E. acervulina and E. tenella. On immunoblots these antisera reacted in a highly specific manner with the homologous 14 kDa antigens, but not with heterologous antigens. In addition, specific binding of the two antisera to oocyst wall fragments of E. acervulina and E. tenella was demonstrated by immunofluorescence. Partial amino-terminal sequences comprising 20 amino acid residues were obtained from the 14 kDa oocyst wall proteins of E. acervulina and E. tenella. They are characterized by an abundance of amino acids containing hydroxyl groups in their side chains (serine, tyrosine, threonine). Binding of the oocyst wall protein of E. tenella by peanut agglutinin indicates the presence of O-linked carbohydrates.
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Wallach M, Smith N, Braun R, Eckert J. Potential control of chicken coccidiosis by maternal immunization. ACTA ACUST UNITED AC 1995. [DOI: 10.1016/0169-4758(95)80208-8] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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Speicher A, Jessberger J, Braun R, Hollnberger H, Stigler F, Manz R. [Postoperative pulmonary function after lung surgery. Total intravenous anesthesia with propofol in comparison to balanced anesthesia with isoflurane]. Anaesthesist 1995; 44:265-73. [PMID: 7785755 DOI: 10.1007/s001010050153] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
After lung resection, early extubation and the rapid return of the patients ability to cooperate is the predominant goal. Propofol anaesthesia is characterised by rapid awakening and recovery of cognitive and psychomotor functions and is consequently desirable for such operations. Experience so far in lung surgery, however, is limited. Besides the level of consciousness we investigated various spirometric parameters after lung resection. Total intravenous anaesthesia was performed with propofol, while balanced anaesthesia was performed with isoflurane. METHODS. A total of 93 patients evaluated electively for wedge excision or lobectomy were enrolled in an open, prospective, randomised, interindividual comparative study. Sixty-three patients could be evaluated with complete data sets. In the evening and the morning before the operation the patients were premedicated orally with clorazepate 0.5-0.7 mg/kg. Anaesthesia was induced in group 1 with propofol (1.0-2.5 mg/kg) and maintained with propofol (4-12 mg/kg) in 50% O2/air. The patients in group 2 received methohexital (1-2 mg/kg) for induction and isoflurane (0.4-2.0 vol%) in 50% O2/air for the maintenance of general anaesthesia. In both groups analgesia was achieved by using fentanyl (up to 10 micrograms/kg) and muscle relaxation by using atracurium. Psychomotor tests (minimal mental state, reaction time) were performed the day before the operation (t1), immediately prior to induction of anaesthesia (t2) and 5 min, 30 min, 60 min, 90 min, 24 h, and 7 days after extubation (t3-t8). Spirometry (forced expiratory volume in 1 s, FEV1; forced vital capacity, FVC; peak expiratory flow, PEF) was carried out at times t1, t2 and t5-t8. RESULTS. The two groups were comparable regarding preoperative status (age, sex, preoperative risk score, psychomotor tests, and spirometric values) and the operation performed (wedge excision/lobectomy, duration of anaesthesia). The extubation time was slightly shorter in the propofol group (18 +/- 8 min) than in the isoflurane group (20 +/- 6 min). Also, the results of the psychomotor tests were somewhat better in the propofol group than those in the isoflurane group. The clearest differences were found in the early postoperative period, but not all differences were significant. Statistically highly significant differences between the two groups were found for the three spirometric parameters. Based on the FEV1 value of the 7th postoperative day, FEV1 taken 60 min after extubation declined by 27.9% in the propofol group vs. 51.7% in the isoflurane group (P = 0.01). At 90 min after extubation the corresponding decline in the propofol group was 26.6%, in the isoflurane group 51.1% (P = 0.003). In addition, the decline of FVC and PEF measured 60 min and 90 min after extubation was significantly smaller in the propofol group than in the isoflurane group. CONCLUSION. The postoperative impairment of lung function after lung resection under propofol anaesthesia is statistically significantly smaller than under isoflurane anaesthesia. Total intravenous anaesthesia with propofol is particularly suitable for this kind of operation.
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Hehl A, Pearson TW, Barry JD, Braun R, Roditi I. Expression of GARP, a major surface glycoprotein of Trypanosoma congolense, on the surface of Trypanosoma brucei: characterization and use as a selectable marker. Mol Biochem Parasitol 1995; 70:45-58. [PMID: 7637714 DOI: 10.1016/0166-6851(95)00003-j] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
Procyclic and epimastigote forms of Trypanosoma congolense express an immunodominant glutamic acid/alanine-rich protein (GARP) that covers the parasite surface. Although GARP shows no sequence similarity to procyclins from T. brucei, the general characteristics of the two sets of surface glycoproteins suggest that they have analogous functions, in much the same way that variant surface glycoproteins with unrelated primary sequences fulfil the same function in bloodstream form trypanosomes. Since T. brucei and T. congolense do not follow the same pathway through the tsetse fly, one possible function of procyclins might be to direct parasites to the correct compartments. As a first step towards testing this hypothesis, we have produced stably transformed procyclic forms of T. brucei in which the GARP coding region has been integrated into a procyclin expression site. GARP can be detected on the surface of these transgenic trypanosomes, uniformly distributed within the endogenous procyclin coat, but there are differences in post-translational modification when it is expressed in T. brucei rather than in T. congolense. The fact that GARP is readily accessible to antibodies which were raised against a bacterial fusion protein led us to examine its potential as a selectable surface marker for transfection. We have established a rapid and simple procedure for isolating stable transformants that provides an alternative to conventional methods of selection for antibiotic resistance.
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Wallach M, Smith NC, Petracca M, Miller CM, Eckert J, Braun R. Eimeria maxima gametocyte antigens: potential use in a subunit maternal vaccine against coccidiosis in chickens. Vaccine 1995; 13:347-54. [PMID: 7793129 DOI: 10.1016/0264-410x(95)98255-9] [Citation(s) in RCA: 87] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
Affinity-purified gametocyte antigens (APGA) from Eimeria maxima, emulsified in Freund's adjuvant, were injected intramuscularly into breeding hens on two or three occasions. As a result, progeny of the immunized hens were partially immune to infection with E. maxima, Eimeria tenella and Eimeria acervulina (with a reduction in total oocyst output of 45-63% as compared with progeny of untreated hens). Thus, APGA in Freund's adjuvant appears to have great potential as part of a maternally applied vaccine against coccidiosis. The ability of APGA to induce partial cross-species protection is most probably due to the existence of conserved epitopes in the different species as indicated by comparative Western blots of E. maxima and E. tenella. Surprisingly, Freund's adjuvant by itself also induced significant levels of maternal immunity to coccidiosis (with a 12-35% reduction in oocyst output in the progeny). In contrast to the purified antigens or Freund's alone, crude extracts from gametocytes as well as other developmental stages, induced little if any significant maternal immunity despite provoking the production of large amounts of parasite-specific IgG, including antibodies to APGA. This result indicates that a successful maternal vaccine against coccidiosis requires, in addition to good recognition of protective antigens, the exclusion of irrelevant antigens from the vaccine preparation.
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Smith NC, Wallach M, Petracca M, Braun R, Eckert J. Maternal transfer of antibodies induced by infection with Eimeria maxima partially protects chickens against challenge with Eimeria tenella. Parasitology 1994; 109 ( Pt 5):551-7. [PMID: 7831090 DOI: 10.1017/s0031182000076423] [Citation(s) in RCA: 54] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
Infection of breeding hens with Eimeria maxima induces production of Eimeria-specific IgG antibodies which are transferred to hatchlings via the egg yolk and confer a high degree of maternal immunity against homologous challenge and partial immunity to infection with another important species, Eimeria tenella. As an example, in an experiment using hatchlings from eggs collected between days 28 and 39 after infection of the hens with 20,000 sporulated E. maxima oocysts, control chicks (challenged with 100 sporulated oocysts) excreted 6.8 +/- 1.2 million (mean +/- S.E., n = 10) or 5.8 +/- 1.2 million (n = 8) oocysts of E. maxima or E. tenella, respectively, compared to 0.9 +/- 0.4 million (n = 5) E. maxima oocysts or 2.2 +/- 0.4 million (n = 9) E. tenella oocysts excreted by hatchlings of infected hens. This represents an 87% reduction in oocyst excretion with regard to E. maxima and a 62% reduction in oocyst excretion with regard to E. tenella in the progeny of the infected hens. In another experiment, eggs were collected from days 28 to 37 and again from days 114 to 123 after infection of the hens with E. maxima and hatchling oocyst excretion rates were 82% and 62%, respectively, reduced for E. maxima and 43% and 41%, respectively, reduced for E. tenella in the progeny of hens infected with E. maxima compared to the progeny of uninfected hens. ELISA and Western blot analyses of maternally-derived IgG revealed a high degree of cross-reactivity to antigens of E. maxima and E. tenella.(ABSTRACT TRUNCATED AT 250 WORDS)
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Smith NC, Wallach M, Miller CM, Braun R, Eckert J. Maternal transmission of immunity to Eimeria maxima: western blot analysis of protective antibodies induced by infection. Infect Immun 1994; 62:4811-7. [PMID: 7927759 PMCID: PMC303191 DOI: 10.1128/iai.62.11.4811-4817.1994] [Citation(s) in RCA: 25] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023] Open
Abstract
Infection of breeding hens with Eimeria maxima induces production of parasite-specific antibodies which are transferred, via the egg yolk, to hatchling chicks. These antibodies (immunoglobulin G) are highly protective, mediating up to a 97% reduction in oocyst excretion in challenged hatchlings. However, the degree of maternally derived immunity transferred by the hens to their offspring declines with increasing time after infection of the hens. This decline in immunity is directly related to declining immunoglobulin G titers. However, sera from highly protected hatchlings recognize only a very few E. maxima proteins on Western blots (immunoblots). In particular, a 230-kDa protein band is outstanding for its association with maternally derived immunity to E. maxima in hatchlings. This band was excised from a sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) preparative gel of crude merozoite protein extract. The SDS-PAGE cutout was emulsified in Freund's adjuvant and injected, intramuscularly, into six breeding hens on two occasions, 2 weeks apart. Eggs were collected from these hens 28 to 39 days after the second injection, and the hatchlings from these eggs were challenged with 150 sporulated oocysts of E. maxima. Subsequent oocyst excretion in these hatchlings was, on average, 54% lower than oocyst excretion by control chicks but only 37% lower (significant at P < 0.05) than that by chicks from hens sham immunized with Freund's adjuvant. The latter result is apparently due to the ability of the adjuvant to induce production of antibodies which recognize Eimeria spp. and thereby transfer some degree of protection to hatchlings. These experiments indicate that protective, maternally derived immunoglobulin G antibodies may be useful for the identification of putative anticoccidial vaccine candidates.
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Braun R, Jahn UR, Schumacher W, Lang R, Thiele H. [Pneumothorax in laparoscopic cholecystectomy (II)]. Anasthesiol Intensivmed Notfallmed Schmerzther 1994; 29:302-3. [PMID: 7948505 DOI: 10.1055/s-2007-996747] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
This case report deals with pneumothorax during elective laparoscopic cholecystectomy in a young woman with no history of severe pulmonary disease. After inflating the capnoperitoneum, pulse oximetry and capnography raised suspicion of pneumothorax whereas the physical examination showed no irregularities. Surgical drapes provided a lack of information from percussion and auscultation. Changing respiratory parameters including the use of pressure-controlled ventilation in absence of tension pneumothorax enabled sufficient ventilation until the insertion of a chest tube. There were no further postoperative complications. Pulse oximetry, capnography and relaxometry proved helpful in monitoring. There may be a benefit from the use of pressure-controlled-ventilation in certain situations, if all changes in volume-controlled-ventilation fail.
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Braun R, St Clair C. Transitional family care: PICU to pediatrics. Crit Care Nurse 1994; 14:65-8. [PMID: 8055690] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
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Groot T, Bicanic D, van Montfort M, Torfs P, Braun R, van Asselt K. The analysis of error in trace gas concentration measurements by intermodulated photoacoustic stark spectroscopy (IMPASS). ACTA ACUST UNITED AC 1994. [DOI: 10.1051/jp4:19947122] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
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Schürch N, Hehl A, Vassella E, Braun R, Roditi I. Accurate polyadenylation of procyclin mRNAs in Trypanosoma brucei is determined by pyrimidine-rich elements in the intergenic regions. Mol Cell Biol 1994; 14:3668-75. [PMID: 7910942 PMCID: PMC358734 DOI: 10.1128/mcb.14.6.3668-3675.1994] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023] Open
Abstract
Polycistronic precursor RNAs from trypanosomes are processed into monocistronic mRNAs by the excision of intergenic sequences and the addition of a 39-nucleotide spliced leader by trans splicing. These mRNAs are also polyadenylated, yet they do not contain the hexamer AAUAAA within their 3' untranslated regions (UTRs). To identify the signals required for the accurate polyadenylation of mRNAs, we tested the effects of deletions in either the procyclin 3' UTR or the downstream intergenic region on the polyadenylation of transcripts from a reporter gene. Deletion of the entire 3' UTR does not affect polyadenylation, but a crucial element is located in the intergenic region and includes a pyrimidine-rich sequence from positions 79 to 112 followed by an AG dinucleotide. Related motifs are also found a similar distance downstream of other genes in both the procyclin and the variant surface glycoprotein expression sites. These sequences bear a strong resemblance to splice acceptor sites, but they are generally several hundred base pairs upstream of the major splice acceptor site of the next gene in the transcription unit. There is evidence, however, that some of them can give rise to alternatively spliced transcripts with unusually long 5' UTRs.
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Glauser A, Braun R. TUBIS, a fossilized retroposon in the tubulin gene cluster of Trypanosoma brucei. BIOCHIMICA ET BIOPHYSICA ACTA 1994; 1218:99-101. [PMID: 8193171 DOI: 10.1016/0167-4781(94)90107-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
The genome of Trypanosoma brucei contains many copies of TRS/ingi, a retroposon like element of about 5 kb length. One vestigial member of this family, TUBIS, is found in the tubulin gene cluster. The element has sequence homologies to reverse transcriptase. The similarity to TRS/ingi is lost after 4 kb, resulting in a 3' truncated element. The sequence following downstream shows similarities to 5' flanking regions of VSG genes.
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Vassella E, Braun R, Roditi I. Control of polyadenylation and alternative splicing of transcripts from adjacent genes in a procyclin expression site: a dual role for polypyrimidine tracts in trypanosomes? Nucleic Acids Res 1994; 22:1359-64. [PMID: 8190625 PMCID: PMC307990 DOI: 10.1093/nar/22.8.1359] [Citation(s) in RCA: 85] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023] Open
Abstract
The procyclin-associated genes (PAGs) of Trypanosoma brucei are located downstream of tandemly repeated procyclin genes and belong to the same alpha-amanitin-resistant polycistronic transcription units. In procyclic form trypanosomes the PAG 1 pre-mRNA is alternatively spliced to give rise to three transcripts of 2.7 kb, 1.8 kb and 1.3 kb. The two larger transcripts contain additional short open reading frames (ORFs) upstream of the major ORF. Trans-splicing to generate these transcripts occurs downstream of three different polypyrimidine tracts. A minor population of procyclin mRNAs is also generated by alternative splicing at a polypyrimidine tract that begins 524 bp upstream of the major splice acceptor site of the procyclin beta-gene. The same polypyrimidine tract is also required for accurate polyadenylation of mRNAs from the upstream procyclin alpha-gene (1). Alternatively polyadenylated forms of PAG 1 mRNAs can also be detected. All polyadenylation sites are found at a similar distance upstream of splice-acceptor sites, in each case with a polypyrimidine tract between them. Our results point to a dual role for polypyrimidine tracts in the maturation of trypanosome mRNAs.
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Smith NC, Wallach M, Miller CM, Morgenstern R, Braun R, Eckert J. Maternal transmission of immunity to Eimeria maxima: enzyme-linked immunosorbent assay analysis of protective antibodies induced by infection. Infect Immun 1994; 62:1348-57. [PMID: 8132342 PMCID: PMC186285 DOI: 10.1128/iai.62.4.1348-1357.1994] [Citation(s) in RCA: 57] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023] Open
Abstract
Vaccination of broiler chickens against Eimeria infection is problematic because of the need to ensure that birds are protected from the time of hatching. We have therefore investigated the feasibility of protecting hatchling broilers via maternal transfer of protective antibodies from hens to their offspring. Oral infection of broiler breeder hens with 20,000 sporulated Eimeria maxima oocysts caused production of antibodies which were passed into the egg yolk and subsequently to hatchlings. The level of specific antibodies in the yolks to unsporulated oocysts, sporulated oocysts, merozoites, and gametocytes was assessed by enzyme-linked immunosorbent assays. The levels in yolks of antibodies to all developmental stages peaked 3 to 4 weeks after infection of the hens. Groups of 10 hatchlings were challenged at 3 days of age by oral infection with 100 sporulated E. maxima oocysts. In the first experiment, the mean 4-day (days 6 to 9 post-infection) total number of oocysts excreted in the feces of chicks from eggs collected 3 weeks after infection of the hens was (0.6 +/- 0.4) x 10(6) (mean +/- standard error) compared with (9.9 +/- 1.4) x 10(6) for the progeny of uninfected hens, which represents a greater than 90% reduction. However, oocyst excretion by chicks from eggs collected 7 or 8 weeks after infection of the hens was only 47 or 68% lower than control values, reflecting declining levels of protective antibodies. In a second experiment, in which the hens were somewhat older and pretreated by intramuscular injection of saline in the emulsifying agent, Arlacel A, the period for which protective antibodies were transferred to hatchlings was prolonged. Thus, oocyst excretion by challenged hatchlings from eggs collected for an 8-week period after infection of the hens was more than 90% lower than oocyst excretion by control chicks, and even hatchlings of eggs collected 19 weeks after infection of the hens showed a 60% reduction in oocyst output. In both experiments, the levels of immunoglobulin G (IgG) antibodies to all developmental stages in yolks or hatchling sera were very strongly correlated with maternally derived immunity to E. maxima. In contrast, parasite-specific IgM or IgA was not detectable, either in egg yolk or egg white. These results demonstrate the ability of IgG antibodies to protect against E. maxima in poultry, thus raising the possibility of using protective maternally derived IgG antibodies to identify potentially protective parasite antigens and indicating the feasibility of using maternal immunization as a means for parasite control.
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