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Z Adam

Publications and source records attributed to Z Adam.

At least 19 recordsLinked to original sources
PubMed2006

[Osteonecrosis of the jaw in the course of multiple myeloma treatment and bisphosphonate administration].

The osteonecrosis of jaws is a phenomena newly described in the connection with bisphosphonate therapy. We describe a case of a 41 years old man with multiple myeloma, who developed the osteonecrosis of jaw in the course of antimyeloma therapy. The men had tooth pain from the beginning of the chemotherapy, but the extraction was performed till one month before high dose chemotherapy with peripheral stem cell transplantations, when the conservative therapy was find unsatisfactory. Bisphosphonate were administered from the beginning of the chemotherapy, the bisphosphonate therapy was started with clodronate and later changed to zoledronate. One year from the tooth extraction the wound did not heeled and therefore resection of the necrotic bone was performed. The pain in the jaw was diminished, but the wound is not completely heeled. The administration of bisphosphonate was stopped after the diagnosis osteonecrosis of the jaws.

Adult↗
PubMed2006

[The value of fluorodeoxyglucose positron emission tomography in multiple myeloma].

UNLABELLED: The aim of this study was investigate the appearance of multiple myeloma on flurorine--18 fluorodeoxyglucose positron emission tomography (FDG-PET). Furthermore the accuracy of FDG-PET in detecting myeloma lesions and its influence on patient's management were evaluated. METHODS: Altogether 50 patients, 13 patients with newly diagnosed multiple myeloma with negative radiographs, 4 patients with solitary plasmocytoma, 27 patients in remission with suspected relapse and 6 patients with monoclonal gammopathy of unknown significance (MGUS) with suspicion for multiple myeloma or other malignancy underwent FDG-PET examination. The results of routinely performed radiographs, and MR or CT imaging modalities as well as the clinical course were used for verification of the FDG-PET results. RESULTS: Focally increased tracer uptake was observed in 3 (23 %) of newly diagnosed myeloma patients with negative radiographs and was verified with CT or MR with followed indication for therapy. The FDG-PET was negative in two cases of newly diagnosed multiple myeloma with negative radiographs, no focal infiltration on MR imagination, but with anemia, high monoclonal imunoglobulin and bone marrow infiltration, which was indication for therapy. In all other cases FDG-PET negativity in asymptomatic myeloma had good prognostic significance; these patients are without progression after with a median follow up 14 (7-20) months. Focally increased tracer uptake was found in 5 of the 27 patients in remission. In 4 cases of them it was due to multiple myeloma relapse, in one case due to ovarial carcinoma. Only in 1 patient the PET-FDP failed to recognize extraosseal progression on the scull. 21 patients had true negative FDG-PET imagination, in 1 case disease relapsed 12 months after FDG-PET examination; the other 20 patients are still without progress of this disease with median follow up 15 (7-20) months. FDG-PET was positive in 2 from the 6 patients with MGUS. In one of them carcinoma of thyreoidea was detected, in second the FDG-PET activity was localized in gut, tumor was verified with CT and colonoscopy. CONCLUSION: In conclusion, FDG PET might contribute to initial staging of radiographs negative multiple myeloma and might be useful for follow up of patients in remission, especially in consecratory multiple myeloma, or in patients with large plasmocelular tumor (> 5 cm) after concomitant radiochemotherapy.

Adult↗
PubMed2006

[Histiocytosis from Langerhans cell in adults--experience of one department and review of treatment alternatives].

Thirteen patients with Langerhans cell histiocytosis (LCH) have been treated in hospital Brno Masaryk University during the last 15 years. In 4 cases of this total amount, the diagnosis was made in childhood and these young adults were referred to our department from Pediatric cancer center. In 9 cases, the diagnosis has been made in people elder than 18 years. The disease recidived in 3 patients with LCH diagnosed in childhood, in one case with neurodegenerative impairment of brain. In 4 patients from the total of 9 with LCH diagnosed in age over 18 years, the disease had aggressive course with several recidives. In one case it was pulmonal and multifocal osseal manifestation, in two cases multifocal osseal disease. Isolated pulmonal form of LCH was diagnosed only in one patient. By the first patient, high dose melphalan and etoposide with peripheral blood stem cell transplantation was performed after failure ofvincristin and prednison therapy and failure of etoposide therapy. The first remission after this high dose therapy lasted only 2.5 years. For relapse second cycle of the same high dose therapy was administered, but the next remission was much shorter. By the two patients with multifocal recidives in bones 2-chlordeoxyadenosine was administered as initial therapy. These patients are followed up for more then 24 months and they are without relapse of this disease. The 2-chlordeoxyadenosine is very efficient in multifocal bone form of LCH and has potential to reach long remission. Therefore in a case of aggressive multifocal disease we would prefer 2-chlordeoxyadenosine therapy as therapy of the first choice.

Adult↗
PubMed2005

Prognostic factors for survival after autologous transplantation: a single centre experience in 133 multiple myeloma patients.

Autologous stem cell transplantation (ASCT) has an established role in the treatment of symptomatic multiple myeloma (MM). Our aim was to analyse the impact of selected prognostic parameters on the survival of patients with MM after ASCT. The new International Staging System (ISS) was also evaluated. A total of 133 MM patients were transplanted in our centre between 1995 and 2002. Following ASCT, 35% of patients were in complete remission (CR) and 60% were in partial remission (PR). The median progression-free (PFS) and overall (OS) survival from transplantation were 29.5 and 68.8 months, respectively. Transplant-related mortality (TRM) was 3%. On multivariate analysis, factors associated with significantly shorter OS were lack of CR after transplant (P = 0.002, hazard ratio (HR): 3.1), stage 3 according to ISS (P = 0.001, HR: 3.0) and age at transplant over 60 years (P = 0.035, HR: 2.0). The status of disease before ASCT did not significantly affect PFS and OS after transplantation. We conclude that ASCT is a safe and effective procedure in MM patients, associated with low TRM. The survival after ASCT was dependent on response after ASCT, stage according to ISS and age.

Adult↗
PubMed2005

[Comparison of standard prognostic factors with the deletion of 13q14 detected by interphase fluorescence in situ hybridization on separated and unseparated bone marrow cells in multiple myeloma].

BACKGROUND: Cytogenetic abnormalities of chromosome 13 are emerging as important prognostic factors in multiple myeloma and have been associated with poor prognosis. METHODS AND RESULTS: The occurrence of 13q14 deletion and other standard laboratory parameters were determined in 40 patients with multiple myeloma. We found that interphase fluorescence in situ hybridization using a locus specific probe for RB1 gene on immunomagnetically selected myeloma cells was more sensitive than non selected cells. The 13q14 deletion was found in 10 of 40 (25.0%) of bone marrow samples without cell selection and in 25 of 40 (62.5%) of samples with CD138+ enriched myeloma cells. Negative correlation was found between albumin and the 13q14 deletion in separated (p = 0.003) as well as in cells without selection (p = 0.010). No significant correlation was found in overall survival of separated and unseparated cells (p = 0.830; p = 0.260) and a similar result was obtained for treatment response after transplantation of separated cells (p = 0.520) or non-separated cells (0.190). CONCLUSIONS: Our results confirm that immunomagnetic selection of CD138+ cells increases the probability of detection of the 13q14 deletion in bone marrow samples. The correlation was found between albumin and the 13q14 deletion in both of type of cells.

Bone Marrow Cells↗
PubMed2005

[Bortezomib (Velcade) in relapsed/refractory multiple myeloma--the first experience in the Czech Republic].

BACKGROUND: Multiple myeloma is the second most prevalent and mostly fatal hematologic cancer. Further advances have been made in understanding the mechanisms involved in the myeloma pathogenesis and elucidation of critical signalling pathways as therapeutical targets. Proteasome inhibitors are the example of this new approach and bortezomib is the first agent in this class to enter clinical trials. METHODS AND RESULTS: In 6 hematological centers in Czech Republic 29 patients with refractory/relapsed myeloma had been treated with bortezomib (Velcade, Millennium Pharmaceuticals) in 2004. The initial dose 1.3 mg/m2 of Velcade was given, in 1 case the dose was adjusted due to pre-existing renal failure to 1 mg/m2. The response was achieved in 17 patients (59%). Four patients had complete, 11 partial and two minor responses. In 5 cases stabilization of disease was observed and 6 patients progressed during the therapy. CONCLUSIONS: Unfortunately, one patient died immediately after the start of therapy due to sepsis. The most common adverse events were thrombocytopenia, anaemia, neuropathy, gastrointestinal complication, renal failure and fatigue. Grade 4 adverse events occurred in 37.9% of patients (4x thrombocytopenia, 2x gastrointestinal, 2x renal failure, 1x sepsis, leucopenia, hepatopathy and anaemia, respectively). Peripheral neuropathic pain of grade 3 was reported in 4 cases, in one patient therapy had to be interrupted due to this complication. We confirmed promising results of phase II trials.

Adult↗
PubMed2004

Second autologous transplantation for multiple myeloma patients relapsing after the first autograft -- a pilot study for the evaluation of experimental maintenance therapies. Report of the prospective non-randomized pilot study of the Czech Myeloma Group.

BACKGROUND: High-dose chemotherapy followed by autologous stem cell transplantation (AT) is accepted as first-line therapy for patients with multiple myeloma (MM), with very good tolerance and low mortality (2-3%). STUDY DESIGN: We tested repeated transplantation with different experimental maintenance therapies in patients with MM relapsing/progressing after first AT. Results were compared using intra-individual analyses, therefore inter-individual differences are excluded (T2 model). PATIENTS AND METHODS: Between January 1997 and January 2003, 32 patients with relapsing/progressing MM after first AT were included in the pilot study, median follow-up was 75.2 months. They received the following experimental therapies: IL-2-activated PBSC (10 pts), pamidronate (4 pts), thalidomide (15 pts), consolidation chemotherapy CED (3 pts). RESULTS: Sensitivity to C-VAD reinduction chemotherapy (4 cycles) was 50%, response to the second AT compared to the first was better in 7, the same in 16 and worse in 9 patients. Toxicity of the first and second transplantation was similar and usually did not exceed grade II (SWOG). Transplant-related mortality was 3% (1/32). Event-free survival after second AT (EFS II) is known in 22 patients; 7 have achieved prolongation of EFS II versus EFS I. In the whole group median EFS I was 15.7 months, median EFS II was 12.9 months, median overall survival (OS) was 79.1 months; 20/32 patients were alive at the time of analysis. CONCLUSIONS: Repeated AT is a feasible and successful strategy in treatment of relapsing MM; response to second AT and toxicity were acceptable and similar to the first AT in our assessment.

Adult↗
PubMed2003

Palliative treatment of cancer anorexia with oral suspension of megestrol acetate.

Megestrol acetate (MA) is a progestational agent, currently known as one of the most effective appetite stimulants in patients suffering from cancer anorexia/cachexia syndrome. Oral suspension of this drug may be particularly useful in patients with far advanced disease, where taking larger amount of pills may lead to the decrease of patient compliance. The influence of oral MA suspension on quality of life and nutritional status was evaluated in 22 patients with far advanced cancer suffering from anorexia and more than 5 per cent weight loss, all beyond the scope of anticancer treatment. Most patients had lung or gastrointestinal cancer. QLQ-C30 questionnaire, visual analogue scale (VAS) for appetite, anthropometry, maximal handgrip strength and laboratory data were obtained before treatment and then after 2, 4, and 8 weeks of therapy. Despite of a known high mortality in this prognostically unfavorable group of patients (36% within two months in this study), overall quality of life after the daily dose of 480-840 mg of MA was improved in 63, 56, and 55% of patients remaining on therapy after 2, 4, and 8 weeks, respectively. Appetite was the most successfully influenced parameter with an improvement in VAS in 95% of cases after 2 weeks of therapy (p=0.0001). The drug was well tolerated by the great majority of patients. Oral suspension of megestrol acetate maybean effective palliative treatment for many patients with far advanced cancer suffering from anorexia/cachexia syndrome.

Administration, Oral↗
PubMed2002

Interleukin-2 activation of haematopoietic stem cells.

BACKGROUND: Recent findings concerning the role of immunity in the eradication of residual malignant disease after autologous haematopoietic stem cell transplantation have led to extensive studies of T-cell and natural killer (NK) mediated anti-tumour effects. Interleukin 2 (IL-2) activation of autologous bone marrow (BM) or peripheral blood stem cells (PBSC) before transplantation is one of the methods of adoptive cell therapy. METHODS: Autologous BM of patients with chronic myelogenous leukaemia (n = 11) and PBSC of patients with multiple myeloma (n = 14) were activated by IL-2 in laboratory conditions with the aim of evaluating the feasibility of this method, the activation of T and NK cells, recovery of active progenitor cells, microbial contamination, and reduction of malignant cell content. RESULTS: Samples of BM (mean 2.6 x 10(6) cells) and PBSC (mean 10.3 x 10(6) cells) were cultured in complete culture medium with IL-2 (6000 Ul/ml) for 24 h. The recovery of CD34+ cells and CFU-GM was 82.5% and 51.5%, respectively, for BM, and 85% and 86%, respectively, for PBSC (mean values). No purging effect was detected by flow cytometry and a small decline in malignant cell contamination was observed by quantitative PCR in BM samples. No microbial contamination occurred during the sample processing. CONCLUSIONS: The described in vitro activation of BM and peripheral blood stem cells using IL-2 was evaluated as a safe and reliable method suitable for clinical application.

Bone Marrow↗
PubMed2002

[Quality of life and tolerance of maintenance therapy in patients with multiple myeloma].

Questionnaires on the quality of life and tolerance of different parts of maintenance treatment were sent to a total of 83 patients with multiple myeloma. All patients were for more than one year on maintenance treatment which involved either interferon alpha monotherapy (I), 3 million u. three times per week till signs of relapse developed or sequence administration of interferon alpha and dexamethazone 40 mg on day 1 to 4, 10 to 13 and 20 to 23 and then after a four-week interval again interferon alpha, again till progression of the disease occurred. The patients evaluated the presence or absence of different undesirable effects of treatment during the first two weeks of treatment and throughout the year and listed their intensity into four categories defined in the questionnaire. The quality of life was evaluated by means of a basic module of the questionnaire of the European Organization for Research and Treatment of Cancer Core Quality of Life Questionnaire version 3.0 (EORTC QLQ-C30). The results of the questionnaire are to a certain extent surprising as from the patients' answers ensues that this maintenance treatment is associated with more numerous undesirable effects than the physicians realized when in contact with the patient. In this summary we can list only the most frequent effects (deterioration of eyesight, impaired sleep, depressions, irritability and unrest, chill, pain in muscles and joints, general weakness and dyspnoea). From the questionnaires on the quality of life ensues a markedly poorer quality of life of these patients as compared with the healthy population. There are however no basic differences between individual groups. The questionnaires were handed only to patients who had maintenance treatment for more than one year and thus patients were eliminated where maintenance treatment was discontinued because of undesirable effects. To give a general idea of the tolerance of the above maintenance treatment the authors mention that to the date of Aug. 31, 2001 113 patients were randomized into one of the branches of maintenance treatment. Maintenance treatment had to be discontinued in 6% patients (in two instances on account of severe hypothyroidism, in one case on account of hallucinations, in three instances on account of severe mental depression caused by this treatment). Reduction of interferon doses in 20% patients usually because of cytopenia but also on account of psychic problem. To the question what length of prolongation of life compensates the undesirable effects of maintenance treatment the following replies were obtained from patients receiving ID, possibly I: 3 months--47.6 and 38.3%, 6 months--4.3 and 10.6%, 9 months--0 and 4.3%, 12 months--47.6 and 46.8% of the addressed patients. In reply to the question whether the patients would prefer, assuming equal effectiveness, a maintenance monotherapy with interferon alpha or dexamethazone more patients preferred interferon to dexamethasone. For practice ensues from this article informing on undesirable effects of maintenance treatment and the effect of maintenance treatment on the quality of life: 1. the necessity of thorough knowledge of physicians of all possible undesirable effects as only a doctor knowing possible undesirable effects of treatment can recognize them, 2. regular monitoring not only of the activity of the basic disease, but also undesirable effects of maintenance treatment and the influence of treatment on the patients' quality of life, 3. the necessity to assess the quality of life in clinical trials as an important parameter for deciding on the way of treatment.

Antineoplastic Agents↗
PubMed2002

[Therapeutic results and changes in prognosis in patients with multiple myeloma in central and northern Moravia over the past 40 years].

OBJECTIVE: The objective of the investigation is evaluation of therapeutic results and the development of the prognosis of patients with multiple myeloma (MM) as a result of consecutive changes of therapeutic procedures in patients of central and northern Moravia in the course of the last 40 years. METHODS AND RESULTS: The analyzed group of 562 patients with MM was concentrated at the Ist and IIIrd Medical Clinic of the Faculty Hospital Olomouc in 1959 - 2000, median age 63 (28-91) male/female ratio 1.1: 1.0. From analysis of Kaplan-Meier survival curves and the results of statistical analysis (log rank test p = 0.0000) ensued that during the evaulated period a very substantial change of prognosis occurred with improvement of theraupeutic results and a significant prolongation of survival in general. The first " turning point" was the introduction of chemotheraphy with alkylating substances with Prednisone (1963-1975), leading as compared with the period of symptomatic treatment alone (1959-1063) to a significant prolongation of the media value of general survival (M) from 8 to 19 months (p = 0.0031) and 3-year survival from 4 to 23 % patients, whereby 10-year survival was only 0 % and 1 %. The second "turning point" was the period from 1976 - 1980 with introduction of systematic chemotherapy using conventional doses of polychemotherapeutic (CP) regimes with better opportunities of supporting treatment (M = 40 months, p = 0.0000; 3-year and 10-year survival 55% and 5.5% patients). The therapeutic results acheived during the subsequent 15 years were however an unsatisfactory advance. During the interval between 1976-1995 in a group of 295 patients divided into 5-year sub-periods remission was acheived (R = < 25 % of the baseline value of M-protein) in 10-24 % patients, an inadequate response (NR) = persistence in > 50 % M-protein) in 55-28 %, prolongation of the median of total survival in 232 of the accessble patients for 44 months and long-term survival of 5 - 10 years after establisment of the diagnosis increased from 25 to 36 % and from 5.5 to 16.5 % patients. The third "turning point" was 1996 characterized by the introduction of high-dosage chemotheraphy with transplantation of autologuos peripheral haematopoietic cells ("HD" therapy with ASCT) leading ina group of so far only 33, assessable patients under 65 years to acheived remission in 71 %, to decline of NR in 10 % only and 5 -year suvival so far in 91 % patients ( p = 0.0037). Improvement of therapeutic results and prognosis of the disease as compared with 1976 - 1995 occurred in the whole group of patients also in 1996 - 2000 (CP and "HD"-therapy with ASCT) characterized by remission in 36 %, NR IN 33 % and 5 -year survival in 57 % (p = 0.030). It was reveled that the application of "HD" theraphy with ASCT led in 1995-2000 to the acheivement of more favorable therapeutic results (R - 71 % NR - 10 %. 5-year survival after the interval which elapsed so far 91 %), as compared with 2 similar groups of subjects under 65 years meeting the criteria of "HD" theraphy with ASCT, but treated only by conventional polychemotheraphy (1991 - 1995 and 1996 - 2000: R - 24 and 32 %, NR - 42 and 23 %, 5-year survival 46 and 68 % of the patients). In the group of 148 patients from the period of 1991-2000 the patients had as regards remission (R) more favourable results as compared with patients with NR concerning the prognosis [M 63 vs.22 months, 5-year and 10-year survival 53 vs. 17 % and 17 vs. 0 % of patients (p = 0.0000)]. CONCLUSION: From the submitted analysis ensured that during the period form 1959 - 2000 in patients with mutiple myeloma in central and northern Moravia as a result of the application of modern methods of chemotheraphy and supporting treatment a significant improvements of results of conventional treatment occurred with a more than 5 fold prolongation of so far assessable median values of survival (8 - 44 months) and long-term 10-year survival of almost one sixth of the patients. The real asset of "HD" theraphy with transplantation of ASCT will be revealed by analyses made after a longer time interval.

Adult↗
PubMed2002

[A questionnaire survey of tolerance and adverse effects of clodronate (Bonefos) in patients with multiple myeloma].

The tolerance of Bonefos was assessed by means of a questionnaire completed by 87 (76.3%) of 114 addressed patients with multiple myeloma who use this drug for prolonged periods. Of 54 patients treated by the oral form 50% were quite free from complaints, and complaints associated with more than half the administrations was reported by 7.4% patients. Of 33 patients treated by infusion 57.6% were quite free from complaints and 9.0% patients had complaints after more than half the administrations. The most frequent undesirable effect reported by the addressed patients were digestive complaints. The latter were reported by 47.3% of the total number of patients who had oral treatment and 42.4% patients who had treatment by the i.v. route, although in both groups this undesirable effect was as a rule observed in less than 50% administrations of the drugs. As this was not a placebo controlled trial (which in this case would not be possible for ethical reasons), it is important to consider the fact that the etiological cause of complaints could be any of the concurrently administered drugs incl. cytostatics and that the number of digestive complaints caused by clodronate will be smaller. A total of 16.4% patients with the oral form and 18.2% patients with the intravenous form reported paraesthesias. This emphasizes that it is advisable or rather necessary to ensure calcium and vitamin substitution also in originally normocalcaemic patients. The preference of a 800 mg capsule to two 400 mg capsules was statistically significant.

Administration, Oral↗
PubMed2001

ATP-dependent association between subunits of Clp protease in pea chloroplasts.

The chloroplast ATP-dependent Clp protease (EC 3.4.21.92) is composed of the proteolytic subunit ClpP and the regulatory ATPase, ClpC. Although both subunits are found in the stroma, the interaction between the two is dynamic. When immunoprecipitation with antibodies against ClpC was performed on stroma from dark-adapted pea (Pisum sativum L. cv. Alaska) chloroplasts, ClpC but not ClpP was precipitated. However, when stroma was supplemented with ATP, both ClpC and ClpP were precipitated. Co-immunoprecipitation was even more efficient in the presence of ATP-gamma-S, suggesting that the association between regulatory and proteolytic subunits is dependent on binding of ATP to ClpC, but not its hydrolysis. To further test this association, stroma was fractionated by column chromatography, and the presence of Clp subunits in the different fractions was monitored immunologically. When stroma depleted of ATP was fractionated on an ion-exchange column, ClpP and ClpC migrated separately, whereas in the presence of ATP-gamma-S both subunits co-migrated. Similar results were observed in size-exclusion chromatography. To further characterize the precipitated enzyme, its proteolytic activity was assayed by testing its ability to degrade beta-casein. No degradation was observed in the absence of ATP, and degradation was inhibited in the presence of phenylmethylsulfonyl fluoride, consistent with Clp being an ATP-dependent serine protease. The activity of the isolated enzyme was further tested using chimeric OE33 as a model substrate. This protein was also degraded in an ATP-dependent manner, supporting the suggested role of Clp protease as a major housekeeping protease in the stroma.

Adenosine Triphosphatases↗
PubMed2001

Plant mitochondria contain proteolytic and regulatory subunits of the ATP-dependent Clp protease.

The proteolytic machinery of plant organelles is largely unknown, although indications so far point to several proteases of bacterial origin. In this study an Arabidopsis thaliana cDNA was isolated that encodes a homologue of bacterial ClpX, a molecular chaperone and regulatory subunit of the ATP-dependent, serine-type Clp protease. Computer analysis of the predicted plant ClpX revealed a putative mitochondrial transit peptide at the N-terminus, as well as overall sequence similarity to other eukaryotic ClpX homologues. Specific polyclonal antibodies were made to the Arabidopsis ClpX protein and used to confirm its localization in plant mitochondria. In addition to ClpX, a ClpP protein located in mitochondria was also identified from the numerous ClpP isomers in Arabidopsis. Localization of this nuclear-encoded protein, termed ClpP2, was determined first by its close sequence similarity to mitochondrial ClpP human, and later experimentally using ClpP2-specific antibodies with isolated plant organellar fractions. In Arabidopsis, transcripts for both clpX and clpP2 genes were detected in various tissues and under different growth conditions, with no significant variation in mRNA level (i.e. 2-fold) for each gene between samples. Using beta-casein as a substrate, plant mitochondria were found to possess an ATP-stimulated, serine-type proteolytic activity that could be strongly inhibited by antibodies specific for ClpX or ClpP2, suggesting an active ClpXP protease. The recent discovery of homologous mitochondrial ClpX and ClpP proteins in mammals suggests that this type of protease may be common to multicellular eukaryotes.

ATPases Associated with Diverse Cellular Activitie↗
PubMed2001

Degradation of unassembled and damaged thylakoid proteins.

To study protein degradation in thylakoid membranes we identified, characterized and cloned thylakoid proteases, and then linked them to known proteolytic processes. Several families of chloroplast proteases were identified and characterized to different extents. FtsH, an ATP-dependent metalloprotease that belongs to the AAA-protein family, was found to be integral to the thylakoid membrane, facing the stroma. It is involved in both the degradation of unassembled subunits of membrane complexes, such as the Rieske Fe-S protein of the cytochrome complex, and the degradation of oxidatively damaged proteins such as the D1 protein of the photosystem II (PS II) reaction centre. Plant genomes contain multiple isomers of this protease but the functional significance of this multiplication is not clear yet. A second protease, the serine ATP-independent DegP, was found to be strongly associated with the luminal side of the thylakoid membrane. Although a specific role has not yet assigned for it, its location suggests that it can degrade luminal soluble proteins as well as luminally exposed regions of thylakoid membrane proteins.

Adenosine Triphosphatases↗
PubMed2001

Bone mineral density in multiple myeloma patients after intravenous clodronate therapy.

Bisphosphonates inhibit osteoclastic bone destruction that may be stimulated by myeloma cells. By this way, bisphosphonates carry the potential to lower the number of new pathological fractures, of hypercalcaemic events, and of intensity of bone pain as was published earlier. Clodronate has been administered orally in most clinical studies so far despite of its poor bioavailability from the gastrointestinal tract. The aim of our study was to evaluate bone mineral density (BMD) changes in 34 newly diagnosed multiple myeloma patients regularly treated by 900 mg of clodronate in slow intravenous infusions on an outpatient basis in two-week intervals for at least 24 months. BMD was evaluated by CT scanning every six months. Initial values of trabecular BMD were only about 60 per cent of age- and sex-adjusted healthy population values. Clodronate therapy seemed to preserve BMD within the period of two or three years. This effect was seen not only in patients responding to chemotherapy but even in the small subgroup of patients with persisting active disease. We conclude that the long-term intravenous clodronate therapy may contribute to the preservation of BMD and thus calcium hydroxyapatite in bones in multiple myeloma patients concomitantly treated by chemotherapy. The administration of clodronate should start early in the course of disease, before BMD has been markedly reduced.

Adult↗
PubMed2001

Chloroplast and mitochondrial proteases in Arabidopsis. A proposed nomenclature.

The identity and scope of chloroplast and mitochondrial proteases in higher plants has only started to become apparent in recent years. Biochemical and molecular studies suggested the existence of Clp, FtsH, and DegP proteases in chloroplasts, and a Lon protease in mitochondria, although currently the full extent of their role in organellar biogenesis and function remains poorly understood. Rapidly accumulating DNA sequence data, especially from Arabidopsis, has revealed that these proteolytic enzymes are found in plant cells in multiple isomeric forms. As a consequence, a systematic approach was taken to catalog all these isomers, to predict their intracellular location and putative processing sites, and to propose a standard nomenclature to avoid confusion and facilitate scientific communication. For the Clp protease most of the ClpP isomers are found in chloroplasts, whereas one is mitochondrial. Of the ATPase subunits, the one ClpD and two ClpC isomers are located in chloroplasts, whereas both ClpX isomers are present in mitochondria. Isomers of the Lon protease are predicted in both compartments, as are the different forms of FtsH protease. DegP, the least characterized protease in plant cells, has the most number of isomers and they are predicted to localize in several cell compartments. These predictions, along with the proposed nomenclature, will serve as a framework for future studies of all four families of proteases and their individual isomers.

Arabidopsis↗