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Biomedical subjects

K Winter

Publications and source records attributed to K Winter.

At least 19 recordsLinked to original sources
PubMed2000

A phase I/II study of external beam radiation, brachytherapy, and concurrent chemotherapy for patients with localized carcinoma of the esophagus (Radiation Therapy Oncology Group Study 9207): final report.

BACKGROUND: A multiinstitutional, prospective study of the Radiation Therapy Oncology Group (RTOG) was designed to determine the feasibility and toxicity of chemotherapy, external beam radiation, and esophageal brachytherapy (EB) in a potentially curable group of patients with adenocarcinoma or squamous cell carcinoma of the esophagus. A preliminary analysis indicated a 17% 1-year actuarial risk of treatment-related fistulas. A final analysis of this study was considered important to determine the median survival time, local control, and late toxicity associated with this treatment regimen. METHODS: Planned treatment was 50 grays (Gy) of external beam radiation (25 fractions given over 5 weeks) followed 2 weeks later by EB (either high-dose-rate 5 Gy during Weeks 8, 9, and 10, for a total of 15 Gy, or low-dose-rate 20 Gy during Week 8). Chemotherapy was given during Weeks 1, 5, 8, and 11, with cisplatin 75 mg/m(2) and 5-fluorouracil 1000 mg/m(2)/24 hours in a 96-hour infusion. RESULTS: Of the 49 eligible patients, 45 (92%) had squamous histology and 4 (6%) had adenocarcinoma. Forty-seven patients (96%) completed external beam radiation plus at least 2 courses of chemotherapy, whereas 34 patients (69%) were able to complete external beam radiation, EB, and at least 2 courses of chemotherapy. The estimated survival rate at 12 months was 49%, with an estimated median survival of 11 months. Life-threatening toxicity or treatment-related death occurred in 12 (24%) and 5 (10%) cases, respectively. Treatment-related esophageal fistulas occurred in 6 cases (12% overall, 14% of patients starting EB) at 0.5-6.2 months from the first day of brachytherapy, leading to death in 3 cases. CONCLUSIONS: In this study, severe toxicity, including treatment-related fistulas, occurred within 7 months of brachytherapy. Based on the 12% incidence of fistulas, the authors continue to urge caution in employing EB, particularly when used in conjunction with chemotherapy.

Adenocarcinoma↗
PubMed2000

Preliminary report of toxicity following 3D radiation therapy for prostate cancer on 3DOG/RTOG 9406.

PURPOSE: A prospective Phase I dose escalation study was conducted to determine the maximally-tolerated radiation dose in men treated with three-dimensional conformal radiation therapy (3D CRT) for localized prostate cancer. This is a preliminary report of toxicity encountered on the 3DOG/RTOG 9406 study. METHODS AND MATERIALS: Each participating institution was required to implement data exchange with the RTOG 3D quality assurance (QA) center at Washington University in St. Louis. 3D CRT capabilities were strictly defined within the study protocol. Patients were registered according to three stratification groups: Group 1 patients had clinically organ-confined disease (T1,2) with a calculated risk of seminal vesicle invasion of < 15%. Group 2 patients had clinical T1,2 disease with risk of SV invasion > or = 15%. Group 3 (G3) patients had clinical local extension of tumor beyond the prostate capsule (T3). All patients were treated with 3D techniques with minimum doses prescribed to the planning target volume (PTV). The PTV margins were 5-10 mm around the prostate for patients in Group 1 and 5-10 mm around the prostate and SV for Group 2. After 55.8 Gy, the PTV was reduced in Group 2 patients to 5-10 mm around the prostate only. Minimum prescription dose began at 68.4 Gy (level I) and was escalated to 73.8 Gy (level II) and subsequently to 79.2 Gy (level III). This report describes the acute and late toxicity encountered in Group 1 and 2 patients treated to the first two study dose levels. Data from RTOG 7506 and 7706 allowed calculation of the expected probability of observing a > or = grade 3 late effect more than 120 days after the start of treatment. RTOG toxicity scores were used. RESULTS: Between August 23, 1994 and July 2, 1997, 304 Group 1 and 2 cases were registered; 288 cases were analyzable for toxicity. Acute toxicity was low, with 53-54% of Group 1 patients having either no or grade 1 toxicity at dose levels I and II, respectively. Sixty-two percent of Group 2 patients had either none or grade 1 toxicity at either dose level. Few patients (0-3%) experienced a grade 3 acute bowel or bladder toxicity, and there were no grade 4 or 5 toxicities. Late toxicity was very low in all patient groups. The majority (81-85%) had either no or mild grade 1 late toxicity at dose level I and II, respectively. A single late grade 3 bladder toxicity in a Group 2 patient treated to dose level II was recorded. There were no grade 4 or 5 late effects in any patient. Compared to historical RTOG controls (studies 7506, 7706) at dose level I, no grade 3 or greater late effects were observed in Group 1 and Group 2 patients when 9.1 and 4.8 events were expected (p = 0.003 and p = 0.028), respectively. At dose level II, there were no grade 3 or greater toxicities in Group 1 patients and a single grade 3 toxicity in a Group 2 patient when 12.1 and 13.0 were expected (p = 0.0005 and p = 0.0003), respectively. Multivariate analysis demonstrated that the relative risk of developing acute bladder toxicity was 2.13 if the percentage of the bladder receiving > or = 65 Gy was more than 30% (p = 0.013) and 2.01 if patients received neoadjuvant hormonal therapy (p = 0.018). The relative risk of developing late bladder complications also increased as the percentage of the bladder receiving > or = 65 Gy increased (p = 0.026). Unexpectedly, there was a lower risk of late bladder complications as the mean dose to the bladder and prescription dose level increased. This probably reflects improvement in conformal techniques as the study matured. There was a 2.1 relative risk of developing a late bowel complication if the total rectal volume on the planning CT scan exceeded 100 cc (p = 0.019). CONCLUSION: Tolerance to high-dose 3D CRT has been better than expected in this dose escalation trial for Stage T1,2 prostate cancer compared to low-dose RTOG historical experience. With strict quality assurance standards and review, 3D CRT can be safely studied in a co

Adult↗
PubMed1999

Irradiation with or without misonidazole for patients with stages IIIB and IVA carcinoma of the cervix: final results of RTOG 80-05. Radiation Therapy Oncology Group.

PURPOSE: The purpose of this study was to evaluate tumor response, progression-free survival, local tumor control, patterns of relapse, and toxicity in patients with Stages IIIb and IVa squamous cell carcinoma of the uterine cervix treated with irradiation or irradiation and misonidazole. This is a report of the final results of the study. METHODS: This study was a prospective randomized Phase III trial performed by the Radiation Therapy Oncology Group (RTOG). Between August 1980 and November 1984, 120 patients with Stages IIIb and IVa squamous cell carcinoma of the cervix were randomized to receive either standard irradiation or standard irradiation and misonidazole. Irradiation consisted of 46 Gy to the pelvis plus a 10 Gy parametrial boost followed by intracavitary brachytherapy or external irradiation boost to the primary tumor. Misonidazole was administered at 400 mg/m2 daily, 2-4 h before irradiation. Patients in the 2 treatment groups were evenly distributed by stage, Karnofsky Performance Status, and positive para-aortic lymph nodes. RESULTS: Sixty-one patients were treated with irradiation alone, and 59 patients received irradiation and misonidazole. Complete response in the pelvis occurred in 44 (75%) of those treated with irradiation and in 38 (64%) of those treated with irradiation and misonidazole. The progression-free survivals were 22% at 5 years for the control group, and 29% at 5 years for the misonidazole group. At the time of last follow-up, 18 patients in the control arm were free of disease, and in the experimental arm, 19 were free of disease. The patterns of failure for those treated with irradiation alone were local-only in 9 patients, distant-only in 8 patients, and local and distant in 11 patients. The patterns of failure for those receiving irradiation and misonidazole were local-only in 3 patients, distant-only in 8 patients, and local and distant in 8 patients. The maximum toxicity experienced per patient was grade 3 in 18%, grade 4 in 8%, and no grade 5 toxicity for those treated with irradiation alone compared to 8%, 2%, and 2%, respectively, for the experimental arm. CONCLUSION: There were no statistically significant differences in pelvic response, disease-free survivals, patterns of failure, or toxicity for the irradiation alone group or for the irradiation and misonidazole group as administered in this study for patients with Stages IIIb and IVa squamous cell carcinoma of the uterine cervix.

Adult↗
PubMed1999

[Verapamil sensitive ventricular tachycardia with myocardial failure in a 2-year-old child].

UNLABELLED: Ventricular arrhythmias can both result from and cause myocardial dysfunction. We report a case of a two-year-old girl with ventricular tachycardia showing signs of heart failure consisting with a tachycardiomyopathy. The therapy with class I and class III antiarrhythmic drugs did not improve the cardiac situation significantly. The cardiologic investigations were consistent with the verapamil-sensitive ventricular tachycardia in young adults. The treatment with verapamil led to a normal rhythm and function of the heart. CONCLUSION: Verapamil-type calcium channel blockers can also be used in children for the treatment of ventricular tachycardias if the corresponding investigations show characteristic findings.

Adult↗
PubMed1999

Measurement of depressive symptoms in cancer patients: evaluation of the Center for Epidemiological Studies Depression Scale (CES-D).

The Center for Epidemiological Studies Depression Scale (CES-D) is commonly used to measure depressive symptomatology in cancer patients, yet there is little known about the psychometric properties of the measure when applied to a cancer population. The aim of this study was to examine the psychometric properties of the CES-D with cancer patients. For purposes of comparison, the psychometric properties of the CES-D were assessed both in women undergoing treatment for breast cancer and women with no history of cancer. The CES-D and other study measures were administered to women undergoing treatment for breast cancer on two occasions: prior to treatment and midway through treatment. The measures were also administered to a group of women similar in age to the cancer patients who had no history of any type of cancer. These healthy comparison subjects were also assessed on two separate occasions. The CES-D was found to have good internal consistency, with alpha coefficients > 0.85 for both groups, as well as adequate test-retest reliability in both groups. Construct validity was demonstrated in two ways, via comparisons between the groups and by comparing the CES-D with measures of fatigue, anxiety, and global mental health functioning. The CES-D was established as a valid and reliable measure of depressive symptomatology in this sample of breast cancer patients. This measure may be appropriate for use in clinical psychosocial research with cancer patients, yet further research is needed to evaluate its usefulness in other cancer populations. The importance of measuring psychological symptoms with standard measures that have been validated with cancer patients is highlighted.

Adolescent↗
PubMed1999

Does androgen suppression enhance the efficacy of postoperative irradiation? A secondary analysis of RTOG 85-31. Radiation Therapy Oncology Group.

OBJECTIVES: To evaluate the effect of immediate androgen suppression in conjunction with standard external beam irradiation (RT) versus RT alone on a group of men after prostatectomy who had indications for adjuvant treatment. METHODS: A national prospective randomized trial (Radiation Therapy Oncology Group [RTOG] 85-31) comparing standard external beam RT plus immediate androgen suppression versus external beam RT alone with delayed hormonal treatment at relapse was initiated for patients with locally advanced adenocarcinoma of the prostate. One hundred thirty-nine of the patients in this trial had indications for adjuvant treatment after prostatectomy (eg, capsular penetration, seminal vesicle involvement). Seventy-one of the patients received RT with immediate androgen suppression (luteinizing hormone-releasing hormone [LHRH] agonist); 68 patients received RT alone with hormonal manipulation instituted only at the time of relapse. RESULTS: With a median follow-up of 5 years, the estimated progression-free survival rate (failure defined as prostate-specific antigen [PSA] greater than 0.5 ng/mL) was 65% for the men who received combination therapy and 42% for those treated by RT alone with hormones reserved for relapse (P = 0.002). Differences in the rates of freedom from biochemical relapse were observed when failure was defined as PSA of 1.0 to 3.9 ng/mL (71% versus 46%; P = 0.008) and PSA greater than 4.0 ng/mL (76% versus 55%; P = 0.05), respectively. No differences were observed between the groups with respect to the end points of local control, distant failure, and overall survival. The use of immediate androgen suppression (ie, LHRH agonists) and the absence of pathologic nodal involvement were independently associated with prolongation of freedom from biochemical relapse by multivariate analysis. CONCLUSIONS: Patients with prostate cancer and indications for postoperative RT should be considered for combined RT and hormonal manipulation. Because statistically significant advantages for this experimental approach could not be defined for all end points studied (in particular, overall survival), efforts should be made to enroll these patients in the recently activated RTOG trial (96-01) comparing RT plus placebo to the combination of RT plus Casodex in the postoperative setting.

Adenocarcinoma↗
PubMed1999

Distribution of TNF-alpha, TNF-R55 and TNF-R75 in the rheumatoid synovial membrane: TNF receptors are localized preferentially in the lining layer; TNF-alpha is distributed mainly in the vicinity of TNF receptors in the deeper layers.

The expression of TNF-alpha and its receptors in the rheumatoid synovial membrane was investigated using immunohistochemistry and immunocytofluorescence. TNF-alpha+ cells (< 10% of all cells) were found in all regions, predominantly in sublining and diffuse infiltrates. The highest percentage of TNF-R+ cells was found in the lining layer (50-90%), with a slight predominance of TNF-R55. In the sublining, fewer cells expressed TNF-R (approximately 50%), mostly TNF-R75. TNF-R75+ cells were also detectable in diffuse infiltrates and lymphoid aggregates (10-50%). These contained only individual TNF-R55+ cells. In diffuse infiltrates, there were slightly more TNF-R55+ cells than in lymphoid aggregates (in both cases < 10%). In sequential sections, TNF-alpha+ cells localized mostly in the vicinity of TNF-R+ cells. Macrophage-like cells appeared to be the predominant TNF-R+ cell type. CD3+ T cells in lymphoid aggregates expressed exclusively TNF-R75. Subsequently, the expression of membrane-bound TNF-alpha, TNF-R55 and TNF-R75 was tested by FACS analysis in isolated RA synoviocytes (n = 7 patients). Only four specimens expressed mTNF-alpha, and that on a low percentage of cells (2 +/- 2.4%; mean +/- SD). In contrast, all specimens expressed higher percentages of TNF-R55 and TNF-R75 (21 +/- 1% and 14 +/- 7.1%, respectively). These results demonstrate that: (1) the percentage of cells expressing soluble/transmembrane TNF-alpha is greatly outnumbered by the percentage of cells expressing TNF receptors; and (2) TNF-alpha-expressing cells are localized in regions expressing substantial levels of TNF receptors. Therefore, the known pro-inflammatory and pro-arthritic effects of TNF-alpha are probably mediated by local interactions between the receptors and their soluble and transmembrane ligands.

Adult↗
PubMed1999

Effects of solar ultraviolet radiation on the potential efficiency of photosystem II in leaves of tropical plants

The effects of solar ultraviolet (UV)-B and UV-A radiation on the potential efficiency of photosystem II (PSII) in leaves of tropical plants were investigated in Panama (9 degrees N). Shade-grown tree seedlings or detached sun leaves from the outer crown of mature trees were exposed for short periods (up to 75 min) to direct sunlight filtered through plastic or glass filters that absorbed either UV-B or UV-A+B radiation, or transmitted the complete solar spectrum. Persistent changes in potential PSII efficiency were monitored by means of the dark-adapted ratio of variable to maximum chlorophyll a fluorescence. In leaves of shade-grown tree seedlings, exposure to the complete solar spectrum resulted in a strong decrease in potential PSII efficiency, probably involving protein damage. A substantially smaller decline in the dark-adapted ratio of variable to maximum chlorophyll a fluorescence was observed when UV-B irradiation was excluded. The loss in PSII efficiency was further reduced by excluding both UV-B and UV-A light. The photoinactivation of PSII was reversible under shade conditions, but restoration of nearly full activity required at least 10 d. Repeated exposure to direct sunlight induced an increase in the pool size of xanthophyll cycle pigments and in the content of UV-absorbing vacuolar compounds. In sun leaves of mature trees, which contained high levels of UV-absorbing compounds, effects of UV-B on PSII efficiency were observed in several cases and varied with developmental age and acclimation state of the leaves. The results show that natural UV-B and UV-A radiation in the tropics may significantly contribute to photoinhibition of PSII during sun exposure in situ, particularly in shade leaves exposed to full sunlight.

Journal Article↗
PubMed1998

Prostate-specific antigen levels are higher in African-American than in white patients in a multicenter registration study: results of RTOG 94-12.

PURPOSE: To compare serum prostate-specific antigen (PSA) levels in a national sample of African-American and white men with prostate cancer, and to attempt to explain any differences by using self-reported individual-level socioeconomic status adjustments. METHODS AND MATERIALS: During 4 1/2 months in 1994-95, 709 patients with nonmetastatic prostate cancer were enrolled in this prospective study; 17.5% were African-American and 82.5% were white. Information about clinical stage, tumor grade, pretreatment PSA, type of insurance, and educational and income status was obtained. Serum PSA levels were measured and racial differences were found; how the differences were influenced by other patient- or tumor-related factors and if the differences could be explained by socioeconomic status disparities were determined. In univariate analyses, factors associated with the mean PSA levels were studied; log-converted values were used to yield a normal distribution. Multivariate analyses were done on log-linear models for description of association patterns among various categorical variables; a perfectly fitted model should have a correlation value (CV) of 1.0. RESULTS: The mean PSA level was higher in African-Americans (14.68 ng/ml) than in whites (9.82 ng/ml) (p = 0.001). Clinical stage (p = 0.001), Gleason sum tumor grade (p = 0.0001), educational level (p = 0.001), and household income (p = 0.03) were also associated with mean PSA levels; age, type of biopsy, and insurance status were not. Disease stage (p = 0.0001), grade (p = 0.0001), education (p = 0.07), and income (p = 0.02) were all associated with PSA levels for whites, but none of these factors were important for African-Americans (all p values > 0.1). The best fitted log-linear model (CV = 0.99) contained PSA (< 10, 10-20, and > 20), Gleason sum grade (2-5, 6-7, and 8-10), race, and two interactions: PSA by race (p = 0.0012) and PSA by Gleason sum (p = 0.0001). Models replacing race for either income (CV = 0.82) or education (CV = 0.82) or both (CV = 0.78) did not fit as well. CONCLUSIONS: African-Americans with nonmetastatic prostate cancer have higher serum PSA levels at diagnosis than whites, implying a higher tumor cell burden. Individual-level household income, education, or insurance status alone or in combination account for racial differences, but only partially.

Analysis of Variance↗
PubMed1998

Percutaneous arterial closure in severely scarred groins: a technical note.

We present a new method to enable the insertion of percutaneous suturing devices in severely scarred groins, using a peel-away sheath. This sheath stabilizes the percutaneous tract for the suturing device. It may help to salvage closure procedures, which would otherwise have to be aborted due to insufficient stiffness of the device shaft.

Catheters, Indwelling↗
PubMed1997

Androgen suppression plus radiation versus radiation alone for patients with D1 (pN+) adenocarcinoma of the prostate (results based on a national prospective randomized trial, RTOG 85-31). Radiation Therapy Oncology Group.

PURPOSE: To evaluate the effect of immediate androgen suppression in conjunction with standard external beam irradiation vs. radiation alone on a group of pathologically staged lymph node-positive patients with adenocarcinoma of the prostate. METHODS AND MATERIALS: A national prospective randomized trial (RTOG 85-31) of standard external beam irradiation plus immediate androgen suppression vs. external beam irradiation alone was initiated in 1985 for patients with locally advanced adenocarcinoma of the prostate. One hundred seventy-three of the patients in this trial had biopsy-proven pathologically involved lymph nodes. Ninety-eight of these patients received radiation plus the immediate androgen suppression (LHRH agonist), while 75 received radiation alone with hormonal manipulation instituted at the time of relapse. RESULTS: With a median followup of 4.9 years, estimated progression-free survival with PSA < 1.5 ng/ml at 5 years was 55% for the patients who received radiation plus immediate LHRH agonist vs. 11% of the patients who received radiation alone with hormonal manipulation at relapse (p = 0.0001). Because all of these patients had locally advanced disease (i.e., pathologically positive lymph nodes), stage does not explain this difference in outcome, and Gleason grade was not statistically different between the two groups. Estimated absolute survival at 5 years for the radiation and LHRH group was 73 vs. 65% for the radiation alone group who received androgen suppression at relapse. Estimated disease-specific survival at 5 years was 82% for the radiation and immediate LHRH agonist group and 77% for the radiation-alone group. CONCLUSION: Patients with adenocarcinoma of the prostate and pathologically involved pelvic lymph nodes (pN+ or clinical stage D1) should be seriously considered for external beam irradiation plus immediate hormonal manipulation over radiation alone with hormonal manipulation at the time of relapse.

Adenocarcinoma↗
PubMed1997

Clinical utility of contrast-enhanced MR angiography.

MR angiography (MRA) is a technique under ongoing discussion. Its non-invasiveness and sensitivity to flow irregularities make it an investigational technique which is easy to apply but which does not always lead to comprehensive results. It requires special skill to perform and also experience for correct interpretation of the results. The lengthiness of the procedure combined with certain physical properties tends to limit its use to mostly neurovascular applications. With the introduction of ultrafast MRA in conjunction with peripheral bolus-injection of extracellular contrast media, a new approach to the imaging of such regions as the thoracic and abdominal vasculature not to mention other vascular territories has become possible. In this paper, considerations of bolus and measurement optimization and timing protocols for dedicated indications are presented together with an overview on the experience acquired to date for CE-MRA of the carotid artery, mediastinal and pulmonary vessels, abdominal vasculature, and peripheral vessels. The main advantage of ultrafast CE-MRA is that patients are subjected to much more tolerable breath-hold investigations with the result that physiological motion such as peristalsis or major pulsation is minimised.

Adolescent↗
PubMed1997

[MR angiography of thoracic blood vessels].

Through the introduction of newly invented high-performance gradient systems to MRI, which enable for echoplanar imaging (EPI), also magnetic resonance angiography (MRA) has gained an entirely new field of applications and techniques. Ultrafast imaging techniques in MRA allow the investigation of larger vascular areas within a single breath-hold-period. Artifacts like motion induced signal misregistrations, dephasing or saturation of the vascular signal are minimized by extremely short echo times. The technique thus requires the intravenous application of a contrast media bolus, usually a gadolinium compound, which is in standard clinical use. Coordination of the bolus injection and the timing of the data acquisition is crucial for optimal results. The first pass evaluation of the contrast media resembles CTA to a certain extend. Due to the fast measurement and the high contrast in contrast-enhanced MRA (CE-MRA) new applications and indications are developed like MRA of the pulmonary vessels. The paper offers considerations and trials for optimization of thoracical CE-MRA. Besides parameter constellation also bolus-optimization is described with respect to the dedicated anatomical premises. Investigations on volunteers and on patients build a basis for suggestions of optimized CE-MRA procedures. To date, a final estimation of the clinical value of the new technique cannot be given since ongoing improvements change the optimal protocol frequently and the potential of further developments is high.

Adolescent↗
PubMed1994

[Flow cytometry detected S-phase fraction and ploidy as prognostic parameters in primary, node-negative breast cancer].

100 specimens of patients with primary node-negative breast cancer were examined by flow cytometry. 64 tumours were shown to be diploid and 36 tumours were aneuploid. The median was the cut-off level for tumours with low S-phase (< or = 10.9%) and high S-phase values (> 10.9%). Aneuploid tumours were associated with high S-phase fraction. The average length of follow-up was 42 months. In univariate analysis for disease-free survival, diploid tumours were shown to have a slightly better prognosis than aneuploid tumours (p = 0.07). This trend could not be shown in multivariate analysis. The S-phase fraction proved to be an independent prognostic factor. Patients, whose tumours had S-phase fractions < or = 10.9%, had significantly longer disease-free survival in univariate (long-rank-test: p = 0.021), as well as in multivariate analysis according to the Cox regression model (p = 0.033). Since, as already stated, the S-phase fraction is an independent prognostic factor for node-negative breast cancer, further adjuvant therapy studies should take this factor into consideration.

Adult↗
PubMed1993

[Determination of drug availability from commercial topical formulations with a multilayer membrane model].

Using the multilayer membrane system (MMS) the drug availability of four drugs from commercial topical formulations are determined. It was found that the availability differs when commercial formulations of beta-methasone-17-valerate, hydrocortisone, diclofenac-Na and clotrimazole were studied. It is shown that the drug availability for characterizing topical formulations has to be taken into account. The MMS applied in this study can be used for the determination of this parameter.

Administration, Topical↗
PubMed1992

Regulatory protein phosphorylation of phosphoenolpyruvate carboxylase in the facultative crassulacean-acid-metabolism plant Mesembryanthemum crystallinum L.

Phosphoenolpyruvate PyrP carboxylase (PyrPC) and PyrPC kinase were copurified from dark-adapted leaves of the common ice plant Mesembryanthemum crystallinum L. with crassulacean-acid metabolism (CAM). Purification by (NH4)2SO4 fractionation, chromatography on Fractogel-DEAE and hydroxylapatite resulted in a PyrPC preparation with a specific activity of 23-25 U/mg protein and a protein kinase activity of 255 mumol Pi.mol-1 PyrPC.s-1. After in vitro phosphorylation, the most prominently phosphorylated polypeptide was identified as PyrPC by immunoblotting and sequencing. Phosphorylation of PyrPC in vitro by incubation with 400 microM MgATP decreased its sensitivity towards malate. When purified in the absence of the protease inhibitor chymostatin, PyrPC lost an N-terminal sequence of 128 amino acids. Although the carboxylation reaction was unaffected, the truncated PyrPC could neither be phosphorylated in vitro nor inhibited by malate. This result and data obtained by limited proteolysis concur with the hypothesis [Jiao, J.A. & Chollet, R. (1989) Arch. Biochem. Biophys. 283, 300-305] that Ser11 is the phosphorylation site of the CAM PyrPC of M. crystallinum. At pH 7.0, the Km for ATP of the protein kinase was 25 microM; phosphorylation of PyrPC was maximal after 30 min at pH 7.0. The kinase showed also activity with histone III-S but not with dephosphorylated casein. It was inhibited by malate. The results show, that reversible protein phosphorylation is an important factor in the regulation of PyrPC in the facultative CAM plant M. crystallinum, similar to C4 and constitutive CAM plants.

Adenosine Triphosphate↗
PubMed1992

[Intrauterine pericardial effusion. Early symptom of a primary symptomatic congenital cytomegaly].

We report of a fetus who was ultrasonographically shown to have growth retardation, oligohydramnios and a pericardial effusion without other components of a hydrops fetalis at 28 weeks' gestation. At 29 weeks' gestation the child was born by cesarean section of pathological CTG. A congenital cytomegaly was diagnosed. The etiological role of the infection for the development of the pericardial effusion is discussed.

Adult↗