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C Jacobi

Publications and source records attributed to C Jacobi.

At least 37 records · Page 2Linked to original sources
PubMed2001

Cloning and characterization of the gene encoding periplasmic 2',3'-cyclic phosphodiesterase of Yersinia enterocolitica O:8.

The gene encoding periplasmic 2',3'-cyclic phosphodiesterase in Yersinia enterocolitica O:8 (designated cpdB), was cloned and expressed in Escherichia coli. This enzyme enables Y. enterocolitica to grow on 2',3'-cAMP as a sole source of carbon and energy. Sequencing and analysis of a 3 kb ECO:RI fragment containing the cpdB gene revealed an open reading frame of 1179 bp, corresponding to a protein with a molecular mass of 71 kDa. The first 25 amino acid residues show features of a typical prokaryotic signal sequence. The predicted molecular mass of the mature peptide is therefore in agreement with the molecular mass estimated by SDS gel electrophoresis (68 kDa). The putative cpdB promoter region contains two possible -10 and -35 regions. Furthermore, the 5' untranslated region contains sequences with significant homology to the cyclic AMP-cyclic AMP receptor protein binding site and the sigma(28) consensus. This region is interrupted by an enterobacterial repetitive intergenic consensus (ERIC) sequence. Deletion of the ERIC element from the cpdB promoter region had no effect on cpdB expression. In the 3' untranslated region, a possible rho-independent transcriptional terminator was identified. The deduced amino acid sequence of the Y. enterocolitica CpdB protein shows 76% identity with CpdB of Salmonella typhimurium and E. coli. CpdB of Y. enterocolitica is exported to the periplasmic space. An isogenic Y. enterocolitica cpdB mutant strain, constructed by allelic exchange, was no longer able to grow on 2',3'-cAMP as sole source of carbon and energy. The CpdB mutant showed no significant change in virulence in an oral and intravenous mouse infection model.

2',3'-Cyclic-Nucleotide Phosphodiesterases↗
PubMed2000

The heterotrimeric Thermus thermophilus Asp-tRNA(Asn) amidotransferase can also generate Gln-tRNA(Gln).

Thermus thermophilus strain HB8 is known to have a heterodimeric aspartyl-tRNA(Asn) amidotransferase (Asp-AdT) capable of forming Asn-tRNA(Asn) [Becker, H.D. and Kern, D. (1998) Proc. Natl. Acad. Sci. USA 95, 12832-12837]. Here we show that, like other bacteria, T. thermophilus possesses the canonical set of amidotransferase (AdT) genes (gatA, gatB and gatC). We cloned and sequenced these genes, and constructed an artificial operon for overexpression in Escherichia coli of the thermophilic holoenzyme. The overproduced T. thermophilus AdT can generate Gln-tRNA(Gln) as well as Asn-tRNA(Asn). Thus, the T. thermophilus tRNA-dependent AdT is a dual-specific Asp/Glu-AdT resembling other bacterial AdTs. In addition, we observed that removal of the 44 carboxy-terminal amino acids of the GatA subunit only inhibits the Asp-AdT activity, leaving the Glu-AdT activity of the mutant AdT unaltered; this shows that Asp-AdT and Glu-AdT activities can be mechanistically separated.

Amino Acid Sequence↗
PubMed2000

The F420H2 dehydrogenase from Methanosarcina mazei is a Redox-driven proton pump closely related to NADH dehydrogenases.

The F(420)H(2) dehydrogenase is part of the energy conserving electron transport system of the methanogenic archaeon Methanosarcina mazei Gö1. Here it is shown that cofactor F(420)H(2)-dependent reduction of 2-hydroxyphenazine as catalyzed by the membrane-bound enzyme is coupled to proton translocation across the cytoplasmic membrane, exhibiting a stoichiometry of 0.9 H(+) translocated per two electrons transferred. The electrochemical proton gradient thereby generated was shown to drive ATP synthesis from ADP + P(i). The gene cluster encoding the F(420)H(2) dehydrogenase of M. mazei Gö1 comprises 12 genes that are referred to as fpoA, B, C, D, H, I, J, K, L, M, N, and O. Analysis of the deduced amino acid sequences revealed that the enzyme is closely related to proton translocating NADH dehydrogenases of respiratory chains from bacteria (NDH-1) and eukarya (complex I). Like the NADH-dependent enzymes, the F(420)H(2) dehydrogenase is composed of three subcomplexes. The gene products FpoA, H, J, K, L, M, and N are highly hydrophobic and are homologous to subunits that form the membrane integral module of NDH-1. FpoB, C, D, and I have their counterparts in the amphipathic membrane-associated module of NDH-1. Homologues to the hydrophilic NADH-oxidizing input module are not present in M. mazei Gö1. Instead, the gene product FpoF may be responsible for F(420)H(2) oxidation and may function as the electron input part. Thus, the F(420)H(2) dehydrogenase from M. mazei Gö1 resembles eukaryotic and bacterial proton translocating NADH dehydrogenases in many ways. The enzyme from the methanogenic archaeon functions as a NDH-1/complex I homologue and is equipped with an alternative electron input unit for the oxidation of reduced cofactor F(420) and a modified output module adopted to the reduction of methanophenazine.

Adenosine Triphosphate↗
PubMed2000

Inflammatory response after laparoscopic and conventional colorectal resections - results of a prospective randomized trial.

BACKGROUND: Short-term benefits of laparoscopic relative to conventional colorectal resections have been demonstrated in randomized controlled trials. It has been suggested that a diminished cytokine and acute-phase response may be responsible for these advantages. METHODS: In a randomized controlled trial, patients underwent laparoscopic (n=30) or conventional (n=30) resection of colorectal tumors. Plasma levels of interleukin-1 receptor antagonist (IL-1RA), interleukin-6 (IL-6), interleukin-10 (IL-10), and C-reactive protein (CRP) were analyzed repeatedly. Postoperative peak levels and area under the curve values were calculated and compared between groups using the Mann-Whitney U-test. RESULTS: Patient characteristics, preoperative cytokine, and CRP plasma levels were not different between each group. Postoperative peak concentrations of IL-6 (P=0.05) and CRP (P<0.001) and the overall postoperative plasma concentrations of IL-6 (P=0.03) and CRP (P=0.002) were lower in the laparoscopic than in the conventional group. Peak and overall IL-1RA (P=0.2; P=0.2) and IL-10 (P=0.4; P=0. 6) plasma concentrations, respectively, were not different between groups. CONCLUSIONS: IL-6 and CRP plasma levels were lower after laparoscopic than conventional colorectal resections. The less intense inflammatory response may be an indicator of the milder surgical trauma inflicted by laparoscopic than conventional colorectal resection.

Acute-Phase Reaction↗
PubMed2000

Moderate controlled hypotension with sodium nitroprusside does not improve surgical conditions or decrease blood loss in endoscopic sinus surgery.

UNLABELLED: STUDY OBJECTIVES To determine if moderate controlled hypotension can improve the dryness of the surgical field in endoscopic sinus surgery. STUDY DESIGN: Randomized, prospective study. SETTING: University-affiliated hospital. PATIENTS: 32 ASA physical status I and II adult patients undergoing endoscopic sinus surgery. INTERVENTIONS: All patients were premedicated orally with chlorazepate. Patients in Group H received 12.5 mg captopril orally prior to surgery. Anesthesia was provided using an intravenous (IV) technique supplemented with nitrous oxide (N(2)O); anesthesia was maintained with boluses of 2 mcg/kg fentanyl and a propofol infusion at rates between 3 and 9 mg/kg/h at the discretion of the anesthetist. In Group H, sodium nitroprusside was infused at a rate of 1 to 2.5 mcg/kg/min to maintain moderate controlled hypotension with mean blood pressure of 65 to 75 mm Hg. MEASUREMENTS AND MAIN RESULTS: Arterial blood pressure was assessed via the radial artery. Readings were recorded prior to intubation, immediately after intubation, at the start of surgery, then at 5, 15, 30, 45, and 60 minutes intraoperatively, and at the end of surgery. Intraoperative blood loss, dryness of the surgical field, adrenocorticotropic (ACTH) hormone, arginin-vasopressin (AVP), cortisol, and the preoperative and postoperative psychomotoric function were examined. At the start of surgery and thereafter, MAP increased in Group N but not in Group H. Throughout surgery, MAP was significantly lower in Group H than in Group N. Blood loss, dryness of the surgical field, ACTH, AVP, and cortisol levels, and psychomotoric function were not significantly different between the groups. CONCLUSION: Intravenous anesthesia supplemented with N(2) is as effective as moderate controlled hypotension when blood loss, visibility in the surgical field, ACTH, AVP, and cortisol are examined.

Adult↗
PubMed1998

No evidence for cell-to-cell coupling in rat colonic crypts: studies with Lucifer Yellow and with photobleaching.

Epithelial cells of exocrine glands (pancreas, lacrimal glands, salivary glands, sweat glands and gastric glands) are intimately linked together by gap junctions. Due to this close junctional coupling exocrine secretion occurs as the well concerted effort of a cell population. Colonic crypts have, on the one hand, anatomical and functional properties resembling those of exocrine glands (mostly crypt base cells) and, on the other hand, properties of absorbing cells (mostly surface cells). In the mid-crypt, depending on the functional status, absorption and secretion can occur. The present study was aimed at examining whether rat distal colonic crypt cells co-ordinate their functional status by cell-to-cell coupling. Two types of measurements were performed: as an independent assessment of cell viability the membrane voltage (Vm) was measured with the fast whole-cell patch-clamp technique; to investigate cellular coupling simultaneously Lucifer Yellow (LY) (mol. wt. 443) distribution was visualized using digital video imaging. LY (500 micromol/l) was included into the patch pipette filling solution. The recorded Vm was -73.4+/-2.3 mV in crypt base cells (n=15), -63.7+/-2.1 mV in mid-crypt cells (n=17) and -52.3+/-2. 9 mV in crypt surface cells. All cells tested reversibly responded to carbachol (100 micromol/l) with a persistent hyperpolarization, as previously shown. Activation of Cl- secretion by elevation of the cAMP concentration with forskolin (5 micromol/l) led to a reversible depolarization. Throughout the duration of each individual experiment [mean experimental time in basal cells: 18.3+/-2.5 min (n=15), in mid-crypt cells: 19.6+/-3.4 min (n=17) and in crypt surface cells: 11.7+/-3.4 min (n=13)] LY dye distribution was solely confined to the patched cell. In addition bleaching of calcein fluorescence in laser scan microscopy was not followed by dye back diffusion, whereas this was clearly the case in pancreatic acini (n=5). These data indicate that colonic crypt cells are not coupled by gap junctions under resting conditions or in the presence of secretagogues.

Animals↗
PubMed1998

The intrathecal, polyspecific and oligoclonal immune response in multiple sclerosis.

We report an extended set of neuroimmunological data detected in cerebrospinal fluid (CSF) from n = 267 patients with definite multiple sclerosis (MS). Known frequencies of oligoclonal IgG (98%), frequencies of intrathecal fractions of IgG, IgA and IgM (72%, 9% and 20%, respectively) were confirmed and quantitated as intrathecal fractions, IgIF or CSF concentrations, IgLOC. Eighty-nine per cent of the patients had a combined 'MRZ-reaction', i.e. intrathecal antibody synthesis (Antibody Index, AI > 1.4) against measles, rubella and/or varicella zoster virus. Frequencies of single antibodies decreased from measles (78%) to rubella (60%), VZV (55%) and HSV (28%). This MRZ-reaction, indicating a chronic autoimmune type disease already at time of first clinical symptoms, is less sensitive but more specific than detection of oligoclonal IgG. With increasing intrathecal IgG synthesis the number of different locally synthesized antibody species were increased as well as the amount per species (increased mean AI values). The concentration of MRZ antibodies in CSF represents together about 2% of intrathecally synthesized total IgG. But, as a very particular result the ratio of intrathecally synthesized specific antibody/intrathecally synthesized JgG was 5-fold higher (0.24-0.85%) compared to the corresponding ratio in blood (0.06-0.17%) of MS patients. This difference between brain ratio and blood ratio is discussed to be indicative for the anti-MRZ antibody forming B-lymphocyte subset in blood migrating into brain at earlier time of pathophysiological start of disease. These results give a concise explanation of neuroimmunological aspects in MS, not understood so far.

Antibodies, Viral↗
PubMed1998

Detection of deletions in the short arm of chromosome 3 in uncultured renal cell carcinomas by interphase cytogenetics.

PURPOSE: Analysis of genetic alterations may facilitate the differential diagnosis of renal cell carcinoma (RCC) subtypes. For genetic classification, deletion of the short arm of chromosome 3 (3p), the hallmark of nonpapillary/clear cell RCC, is a major diagnostic criterion. Because of the limited routine applicability of cytogenetics and molecular genetic techniques we investigated interphase fluorescence in situ hybridization (FISH) for the detection of this aberration in RCC. MATERIALS AND METHODS: Using seven chromosome 3 specific probes FISH was performed on isolated nuclei from 26 uncultured sporadic RCC. RESULTS: Alterations of chromosome 3 were identified in 19 RCC (73%). Monosomy and/or 3p-deletions were observed in 15 of 19 (79%) non-papillary/clear cell RCC but not in other morphologic subgroups. The median percentage of cells in a specimen containing loss of 3p was 45%. Deletion mapping indicated that large deletions affecting different regions in 3p are predominant. Chromosomal region 3p24 was recurrently involved in all RCC with a deletion in 3p. CONCLUSION: Interphase FISH for the detection of loss in 3p provides a sensitive and feasible method for the genetic classification of kidney tumors and the delineation of recurrently deleted regions in 3p.

Adult↗
PubMed1997

Drug specific antibodies: T-cell epitope-lipopeptide conjugates are potent adjuvants for small antigens in vivo and in vitro.

To generate conventional or monoclonal antibodies for the serological detection of drugs, antibiotics, toxins and other low molecular mass substances, a suitable and effective adjuvant is needed. Lipopeptides derived from a major component of the bacterial cell wall constitute potent nontoxic and nonpyrogenic immunoadjuvants when mixed with conventional antigens. Here we demonstrate that the synthetic lipopeptide N-palmitoyl-S-[2,3-bis(palmitoyloxy)-(2R,S)-propyl]-(R)-cysteinyl- serine (P3CS) coupled to a Th-cell epitope (P3CS-Th) can efficiently enhance the specific immune response against low molecular weight compounds in different species. In the presence of the synthetic lipopeptide P3CS-Th, the peptides which are per se non-immunogenic stimulated a specific humoral immune response in mice after intraperitoneal application. Mixtures containing adjuvants without the Th sequence showed no significant antibody induction. A marked enhancement of the humoral immune response was obtained with the low molecular mass antigens Iturin AL, Herbicolin A and Microcystin (MLR) coupled to poly-l-lysin (MLR-PLL), in rabbits and in chickens. Lipopeptide-Th cell epitope conjugates also constituted adjuvants for the in vitro immunization of either human mononuclear cells or mouse B-cells with MLR-PLL; after fusion of the immunized cultures with the heteromyeloma cell lines CB-F7 or the mouse myeloma cell line SP 2/0, respectively, we observed a significantly increased yield of antibody secreting hybridomas.

Adjuvants, Immunologic↗
PubMed1996

[Lymphadenectomy in surgery of bronchial carcinoma].

Since 1982 a total number of 1062 patients underwent surgical treatment of bronchogenic carcinoma. There were 972 men and 89 women, with a mean age of 62.5 years. In 484 cases a squamous cell carcinoma was diagnosed and in 416 patients an adenocarcinoma. An alveolar cell carcinoma was found in 54 and a polymorphocellular carcinoma in 68 patients respectively. 334 patients were found to be in stage I, 233 in stage II and 438 patients were in stage IIIa. The 5-year survival rate was 57.2% in stage I and 32.5% in stage II. The group of patients with N2 lymph node metastasis according stage IIIa showed a very poor 5-year-survival rate of 12.3%. A standard therapeutical procedure according to a multimodal concept is necessary to improve these patients' long-term survival. Systemic lymphadenectomy is essential for adequate therapy.

Adult↗
PubMed1992

[Resection of esophageal cancer without thoracotomy by manual dissection and eversion stripping].

At the department of surgery of the university of Cologne-Lindenthal, 184 patients (142 with squamous cell carcinoma of the esophagus, 42 with adenocarcinoma of the gastroesophageal junction) underwent blunt dissection of esophageal cancer between 1983 and 1991. Tumor expansion classified by the pathologist was stage I in 13.6%, stage II in 31.0%, stage III in 41.8%, and stage IV in 13.6% of all cases. Histological tumor differentiation was graded well in 4.3%, moderate in 71.7%, and poor in 19.6%. Principally a gastric tube was used for esophageal replacement (96.3%), while interposition of the large bowel was performed in 5 cases. All the patients were prospectively monitored for perioperative complications. 64.7% fared without any complications intraoperatively. The most frequent intraoperative complications were damage of the pleura parietalis (16.3%), rupture of the tumor during dissection (13.0%), and lesion of the spleen (11.4%). 29.9% of the patients had a postoperative course without any complications. Pleural effusion (38.6%) and insufficiency of the cervical anastomosis (22.8%) were the most frequent complications seen postoperatively. Hospital mortality amounted to 6.0%. Six months after the operation most patients deemed their quality of life satisfying or excellent, respectively. The cumulative survival rate (without hospital mortality) was 78.3% after the first year, 24.7% after the third year and 20.6% after the fifth year.

Adenocarcinoma↗
PubMed1992

[Surgical treatment of esophageal cancer: Part I. European results 1980-1991].

During the past 10 years, postoperative mortality associated with resection of oesophageal carcinoma has been reduced from 30% to 11%. However, all efforts to improve longterm survival with extensive excisional procedures and adjuvant chemotherapy and radiotherapy have failed. Fifty-three of 100 patients presenting to the surgeon with an oesophageal carcinoma have resectable disease. Six of them will die from postoperative complications and 47 patients will be discharged from the hospital after an average of 3 weeks. Of these patients, 30 will survive the first, 17 th second, and 7 the fifth year. Although in may be possible to further reduce postoperative complications and mortality, the chances of improving the long-term prognosis of patients with oesophageal carcinoma seem small.

Esophageal Neoplasms↗
PubMed1988

Clinical relevance of increased neuron-specific enolase concentration in cerebrospinal fluid.

Neuron-specific enolase (NSE) concentrations in cerebrospinal fluid (CSF) and serum have been studied by an EIA-method using monoclonal antibodies against human NSE. In a control group (n = 24) the mean NSE value (+/- SD) in CSF was 10.8 (+/- 4.5) ng/ml. Increased NSE values in CSF (greater than or equal to 20 ng/ml, ie greater than or equal to means + 2s) have been detected in 33/172 patients with the following neurological diseases: CNS tumors (6/30), infarctions (6/36), cerebral ischemias (5/25), inflammatory diseases (7/33), epilepsias (3/10) and miscellaneous neurological diseases (6/38). The NSE assay in CSF was not specific for a single neurological disease. In 9% of all patients with an organic neurological disease the increased NSE concentration was the only abnormal result in the CNS out of variables routinely determined in CSF. The discrimination between an organic and psychogenic origin of epilepsy may be possible by an NSE analysis in CSF. The NSE assay in CSF can be recommended as an unspecific screening parameter for pathological organic CNS processes.

Antibodies, Monoclonal↗
PubMed1988

Meningeal carcinomatosis: origin of local IgG production in the CSF.

We found that eight of 22 patients with meningeal carcinomatosis from different primary tumors produced local IgG in the CSF, as indicated by elevated IgG index and/or oligoclonal IgG subfractions. Local IgG production, when present, appears in an early stage of the leptomeningeal manifestation and remains detectable over extended observation periods. In autopsied cases with local IgG production, we observed numerous perivascular round-cell infiltrates containing plasma cells and large lymphocytes within the leptomeningeal tumor tissue. After incubation with immunoperoxidase, only these cells showed IgG-specific staining, indicating the site of local IgG production.

Adult↗
PubMed1986

Sensitive quantitation of carcinoembryonic antigen in cerebrospinal fluid and its barrier-dependent differentiation.

Modification of an enzyme immunoassay using beads as solid phase allows the detection of 3 pg/ml carcinoembryonic antigen (CEA). The beads are shown to be advantageous for the extraction of proteins in highly diluted antigen solutions thus replacing a need for concentration of the sample. The mean concentration of CEA in pooled cerebrospinal fluid (CSF) from 120 control persons was shown to be 2.7 pg/ml. The mean of the CSF/serum concentration quotients of CEA was 0.0015 for normal blood CSF barrier function with a corresponding mean albumin CSF/serum quotient of 0.0048. From the ratio of these two quotients (QCEA/QA = 0.31) and the corresponding biological variation we constructed the normal range of an evaluation graph. In the range of a blood CSF barrier dysfunction, the discrimination line between values with or without a local CEA synthesis in brain was determined to be QCEA = 0.7 QA. Twenty-five out of 383 control persons and 29 out of 45 patients with a tumor metastasis had evaluable quotients. The evaluation graph had a high significance with respect to the identification of tumor metastasis: from a group of patients with a confirmed leptomeningeal metastasis 13 out of 13 and from a group of patients with intraparenchymatous tumor metastasis 10 out of 16 could be identified by CSF analysis. The CEA CSF/serum concentration quotient fits well in the concept of a molecular size-dependent filter function of the blood CSF barrier.

Blood-Brain Barrier↗
PubMed1986

The clinical relevance of locally produced carcinoembryonic antigen in cerebrospinal fluid.

Sixteen out of eighteen meningeal carcinomas (89%) secreted carcinoembryonic antigen (CEA) into the cerebrospinal fluid, where it could be quantified separately from the portion originating from the circulating blood. The discrimination of both fractions was performed according to an empirical approach analogous to the immunoglobulins. Only 47% of the intraparenchymal carcinomas released CEA into the CSF compartment and it is possible that the extra-cellular space of these tumour sites does not communicate with the free CSF space. Extradural metastases may cause an impairment of the blood-CSF barrier via restrictions of the CSF fluid turnover, but the dura remains impermeable for the tumour marker. Seven out of 54 primary brain tumours (13%) released carcinoembryonic antigen into the cerebrospinal fluid.

Blood-Brain Barrier↗