Caged probes: a novel tool in studying symplasmic transport in plant tissues

Caged probes offer a novel approach to study plant cell-to-cell communication. Instead of introducing fluorescent molecules into cells by microinjection, their caged counterparts can be preloaded into the tissue by diffusion. Following spatially controlled photoactivation, movement of the uncaged fluorochrome can be followed in time and direction by confocal laser scanning microscopy. In the onion bulb scale epidermis used as a model system, symplasmic transport of the tracer out of a target cell was followed. Transport via the symplasmic pathway was challenged by plasmolysing the tissue. The experiments confirmed the symplasmic nature of tracer transport.

Reappraisal of thromboangiitis obliterans--a pathological contribution

Thromboangiitis obliterans (TAO), the Winiwarter-Buerger disease, is a vasoocclusive disease of unknown etiology which typically affects medium-sized extremital vessels of young male smokers. While the diagnosis of TAO is largely based on patients' presentation and clinical criteria, pathological substrates have been poorly defined and repeatedly disputed. Comparing the histology and immunohistochemistry of TAO especially with those of arteriosclerosis obliterans (ASO) and thromboembolism in two larger studies, we recently identified several features with significant meaning for the differential diagnosis. The unique tissue appearance of TAO is in favor of a general disorder of minute vessels indicating periarteritis rather than pure endarteritis, whereas an inflammatory reaction directed to the internal elastic lamina corresponds with the severity of disease. Since TAO or its syndromic equivalent is probably more common than currently diagnosed, the presented pathological criteria may help to identify latent cases, the overlap with ASO, and untypical organ involvement of TAO.

[Morphe and function - Kurt Goldstein's understanding of the Babinski phenomenon]

Viewed in terms of the theory of science and medicine, one of the striking features characterizing the period extending from the end of the 19 (th) century to the first third of the 20 (th) century was the formulation of concepts of etiopathogenesis. Existing theories on the morphe and structure of human cells, tissues, and organs were enlarged by models focusing on the function of these elements and structures of the organism. This enlargement of etiopathogenic concepts, including biperspective observation, occurred in the fields of internal medicine (Gustav von Bergmann), psychiatry (Erwin Straus), and neurology (Kurt Goldstein). In the light of Goldsteins's understanding of the Babinski phenomenon, the present paper seeks to show what fundamental questions spring from a theory of the human organism that takes into account both morphe and structure and function. Studies of historical models of this kind are both meaningful and justified in that they include constructs and guiding theoretical principles (like, for instance, biperspective access to the patient and his/her disease) which are of immediate relevance in addressing problems with which psychosomatics and medicine are challenged today.

Insulin-like growth factor I (IGF-I) stimulates proliferation but also increases caspase-3 activity, Annexin-V binding, and DNA-fragmentation in human MG63 osteosarcoma cells: co-activation of pro- and anti-apoptotic pathways by IGF-I

Insulin-like growth factor-I (IGF-I) was found to promote proliferation, cell survival, and inhibition of apoptosis. But in some instances, IGF-I was found to mildly induce apoptosis, i. e. Fas-mediated apoptosis in human MG63 osteosarcoma cells. In the present study, we intended to further investigate IGF-I dependent pathways leading either to proliferation and cell survival or to cell death. MG63 osteosarcoma cells were treated with serum free medium alone or in combination with IGF-I, a neutralizing antibody against the human IGF-I receptor (alphaIR-3) or non-immune control IgG (1) for two to six days. We investigated cell survival (cell count), proliferation (CD71-FACS), apoptosis (Annexin-V-FACS, Caspase-3 activity, PCD) and anti-apoptosis (112-Ser Bad phosphorylation), and regulation of IGF-I receptor surface expression (IGF-I receptor-FACS). We found that IGF-I treatment (48 h) stimulated cell growth and proliferation, but also mildly induced apoptosis. IGF-I activated specific apoptotic pathways (Caspase-3 activation, Annexin-V binding and DNA degradation), as well as anti-apoptotic signals (Bad phosphorylation at serine 112). alphaIR-3 blocked cell proliferation, strongly induced apoptosis, and inhibited Bad-phosphorylation. Thus, IGF-I treatment overall resulted in increased tumour cell mass, despite a detectable stimulation of apoptosis; in other words proliferation exceeded cell death. If IGF-I was first added on day 0, 2, or 4 of serum free culture, we found decreasing IGF-I specific effects on proliferation and apoptosis. In parallel, we found a down-regulation of IGF-I receptors (FACS) by serum withdrawal, which was partly reversed if IGF-I was added. Therefore receptor number might have an impact on IGF-I function in MG63 cells. In conclusion, co-activation of apoptosis and proliferation by IGF-I might result in higher cell turnover in MG63 osteosarcoma cells. Furthermore, in sarcomas or carcinomas showing clinical association to IGF-I levels and malignancy, IGF-I dependent apoptosis and proliferation could be a significant mechanism of malignant tumour growth.

[American cutaneous leishmaniasis: special features in diagnosis and therapy]

HISTORY AND CLINICAL FINDINGS

Three weeks after returning from a trip to Guatemala, a 33-year-old man developed two ulcers with indurated edges on his right leg and painful lymph nodes in the right groin. His general condition was not impaired.

EXAMINATIONS

Histological examination revealed cellular infiltrates of the corium by lymphocytes and plasma cells, always accompanied by epithelial cells and multinuclear giant cells. Special stainings were unable to detect pathogens but Leishmania brasiliensis was identified using PCR. The Leishmania culture remained negative.

THERAPY AND COURSE

After 7-day intravenous therapy with 20 mg/kg/d pentostam (pentavalent antimonial compound), the patient developed gastrointestinal complaints, coupled with a marked elevation of transaminases. Therapy was discontinued until the transaminase values normalized, then continued in reduced dosage (12 mg/kg body weight) for 23 days. The ulcers and lymphadenitis healed under this therapy.

CONCLUSION

The diagnosis of American cutaneous Leishmaniasis may be complicated by the relative lack of pathogens in the lesions. PCR diagnosis are very helpful here. The therapy must be systemic owing to the danger of progression to mucocutaneous Leishmaniasis. The standard therapeutic pentostam has, however, a high rate of side effects and administration is exclusively intravenous.

Polymorphism in the peroxisome proliferator-activated receptor alpha gene influences the risk for Alzheimer's disease

The peroxisome proliferator-activated receptor alpha (PPAR-alpha) is a member of the steroid hormone super family of ligand-inducible transcription factors, involved in glucose and lipid metabolism. We screened for polymorphisms in the PPAR-alpha gene and detected two known polymorphisms located in exon 5 and intron 7. These polymorphisms were investigated for their possible association with Alzheimer's disease (AD) and for their effect in carriers of an insulin gene (INS) polymorphism. The PPAR-alpha C --> G polymorphism in exon 5 (L162V) was associated with AD, in that the V-allele was more frequent in AD patients than in healthy subjects. Further data analysis revealed that carriers of an PPAR-alpha L162V V-allele and an INS-1 allele presented with an increased risk for AD. Cerebrospinal fluid amyloid-beta levels were influenced by PPAR-alpha L162V genotype. These results suggest, that PPAR-alpha polymorphism may be a risk factor for AD.

Chronic cutaneous sclerodermoid graft-versus-host disease: evaluation by 20-MHz sonography

BACKGROUND

Chronic graft-versus-host disease (GVHD) is an immunological disorder frequently occurring as a late consequence of allogeneic bone marrow transplantation. Two variants, cutaneous lichenoid and sclerodermoid, have been described, based on clinical and histopathological examinations. It is, however, difficult to determine non-invasively the degree of cutaneous GVHD in vivo. Ultrasonographic methods have recently provided us with the means for objective and non-invasive monitoring of the dynamics of many chronic skin diseases.

AIM, PATIENTS AND METHODS

In five patients with chronic cutaneous sclerodermoid GVHD skin thickness was measured with a 20-MHz B-mode ultrasound scanner (DUB 20S, taberna pro medicum, Lüneburg, Germany) in a clinically well-defined target skin lesion. Additionally cutaneous GVHD was assessed histologically before and after treatment.

RESULTS

In all patients before treatment the corium of sclerotic skin was thicker than the corresponding areas of healthy skin. The skin thickness was increased from 45% to 83%. In the subcutaneous tissue proper echo-rich reflexes were prominent, representing the correlate of subcutaneous fibrotic trabeculae. In all patients ultrasonographic evidence of regression was shown (decrease of skin thickness by 18-83%). Moreover, it was demonstrated that quantitative assessment of skin thickness is feasible.

CONCLUSIONS

In this paper we describe the detailed sonographic features of cutaneous sclerodermoid GVHD for the first time. As the method is simple and non-invasive, repeated examinations are possible. This provides the basis for monitoring treatment effects and efficient follow-up in these chronically progressive clinical conditions after bone marrow transplantation.

Development of Cuscuta species on a partially incompatible host: induction of xylem transfer cells

The growth of dodders, Cuscuta reflexa and Cuscuta japonica, on the partially incompatible host poinsettia ( Euphorbia pulcherrima) is studied. Poinsettia responds by bark growths to the formation of the dodder haustoria and prevents dodder from obtaining normal growth. The growth instead becomes extremely branched, coral-like, and dodder lacks the ability to form haustoria. After a period of coral-like growth, long shoots sprout, resembling the normal growth. These long shoots mark an ending phase for dodder, which dies shortly after without having flowered. During the coral-like growth phase, dodder develops transfer cells in the parenchyma cells bordering the vessels of the xylem in the shoot. The transfer cells have not been observed when dodder is grown on the compatible host Pelargonium zonale. A coral-like growth phase has also been observed at the establishing phase when dodder is grown in vitro on agar; later a more normal growth form takes over. In this coral phase, xylem transfer cells are also developed. The fluorochromes carboxyfluorescein and Texas Red were loaded into the host in the phloem and xylem, respectively, and detection of these fluorochromes in the dodder stem indicated that a functional haustorial contact developed for both vascular systems. The results show that Cuscutaspp. have the genetic ability to develop xylem transfer cells and use this in response to developmental stress.

Graft patency and clinical outcome of femorodistal arterial reconstruction in diabetic and non-diabetic patients: results of a multicentre comparative analysis

OBJECTIVE

in diabetic patients with critical limb ischaemia (CLI) an inferior success rate following infrainguinal bypass surgery is quite often suggested. The aim of this retrospective analysis was, therefore, to evaluate the graft patency and, particularly, the clinical outcome at 1 year in diabetic compared with non-diabetic patients.

MATERIAL AND METHODS

two hundred and eleven patients (diabetics 94; non-diabetics 117) with femorodistal reconstruction for CLI were studied. Groups were comparable with regard to the Fontaine classification, the distribution of vascular risk factors, graft material, distal anastomosis site, and the angiographic runoff grading.

RESULTS

diabetes did not adversely affect graft function. For diabetics and non-diabetics primary cumulative patency rate at 1 year was found to be 66 and 56%, respectively (p=0.10) and a virtually identical limb salvage rate of 85 and 83% was achieved (p=0.76). With regard to healing of ischaemic foot ulcers a trend against diabetics was noted with a healing rate of 81% compared to 96% in non-diabetics at 1 year (p=0.067); gangrenous foot lesions could be equally remedied in 94% and in 87% among patients with and without diabetes (p=0.44). The survival rate of diabetics, however, was significantly lower with 78% at 1 year compared with 95% in non-diabetic patients (p=0.0004).

CONCLUSIONS

our preliminary results support the view that infrainguinal bypass grafting can be safely done even in diabetics. Despite increased mortality in this group, liberal indication for reconstructive vascular surgery seems to be justified by favourable patency rates and clinical outcome in selected patients.

Elimination costs for different wastewater compounds

The present report presents the system and discusses the results of the cost calculation for the reduction/elimination of different wastewater and sludge compounds. These costs were calculated for different types of processes at 102 wastewater treatment plants of Emschergenossenschaft/Lippeverband and Aggerverband. Comparing enhanced biological phosphorus removal and precipitation, one of the results indicates that in general the costs for elimination of one kilogram of phosphorus are lower in the plants in which only chemical precipitation is used for P reduction. Further results of the cost calculation will be presented with a discussion of their possible influence on planning decisions.

High-dose chemotherapy with autologous stem cell rescue in children with nephroblastoma

Children with Wilms tumor who have a particular risk of failure at relapse or at primary diagnosis were treated with high-dose chemotherapy (HDC) and autologous peripheral blood stem cell rescue in order to improve their probability of survival. From April 1992 to December 1998, 23 evaluable patients received HDC within the German Cooperative Wilms Tumor Studies. Nineteen were given melphalan, etoposide and carboplatin (MEC); the others received different regimens. The dose of carboplatin was adjusted according to renal function. Indications for HDC were high-risk relapse in 20 patients, bone metastases in two patients and no response in one patient. Fourteen of 23 patients are alive after a median observation time of 41 months, 11 of 14 in continuous complete remission, three in CR after relapse post HDC. The estimated survival and event-free survival for these patients are 60.9% and 48.2%. Twelve children relapsed after HDC; nine of them died within 12 months and three are surviving from 20 to 33 months after relapse. The main toxicities were hematologic, mucositis and renal (tubular dysfunction; intermittent hemodialysis in one patient). There were no toxic deaths. About half of the children suffering from Wilms tumor with very unfavorable prognostic factors survive disease-free after HDC for over 3 years. Besides hematological toxicity, mucositis and infections, renal function is at risk during HDC. With dose adjustment on glomerular filtration rate, however, no permanent renal failure was observed.

[Fibrous dysplasia: differential diagnosis from Paget's disease]

HISTORY AND CLINICAL FINDINGS

A 27-year-old woman presented with chronic diffuse bone pain and skeletal deformities. Since the age of 3 years she had occipital hyperostosis. Since aged 13 years she had symptoms indicating spinal root involvement due to hyperkyphosis. For the last 6 years there was evidence of destructive and hyperplastic changes in the region of the middle ribs. Alkaline phosphatase (APL) had been elevated (> 250 U/l) for several years. Three years before the present admission the patient had been hospitalized elsewhere because of bone pain and had received intermittent infusions of pamindronate to a total of 600 mg.

INVESTIGATIONS

Laboratory tests showed moderate rise in bone-specific APL and osteocalcin. Conventional x-ray examinations and computed tomography showed lesions in the occipital bone, sella turcica and ethmoid air cells. Several thoracic vertebral fractures were demonstrated. Skeletal scintigraphy indicated enrichment in the occipital and supraorbital regions, as well as in vertebrae and ribs. Dual energy x-ray absorptiometry (DEXA) showed osteopenia. Bone biopsy from the occipital lesion revealed fibrous dysplasia.

TREATMENT AND COURSE

The diagnosis of fibrous dysplasia having been confirmed, cyclical treatment with i.v. pamidronate was given for 6 months. It was well tolerated and lessened the pain without changing the objective findings.

CONCLUSION

In case of uncertain radiological and scintigraphic findings in the differential diagnosis of fibrous dysplasia, Paget's disease or bone tumor, it is essential to obtain a biopsy and, if available, perform gene analysis.

[Kurt Goldstein's understanding of amnesic aphasia and its underlying disorder - an early model of the pensée opératoire of the French psychosomatic school?]

Kurt Goldstein's understanding of amnesic aphasia in some regards anticipated the model of the pensée opératoire, a concept developed during the 60's and 70's by the French psychoanalytical school of psychosomatics. Goldstein interpreted amnesic aphasia within the framework of a "basic disorder". Closely following the philosopher Ernst Cassirer, Goldstein described amnesic aphasia as an expression of a general alteration following localized or generalised brain damage. Due to various historical events (world war, fascism, the holocaust) as well as developments during the 20(th) century (dominance of the English language in many areas of science), these connections were forgotten or were no longer recognised as such. Without wanting to determine the extent to which the concept of pensée opératoire possesses validity, one can interpret Goldstein's reflections on aphasia as a heretofore unreceived preliminary model of the psychosomatic concept of the French School.

[Liposomal daunorubicine combined with cytarabine in the treatment of relapsed/refractory acute myeloid leukemia in children]

BACKGROUND

First-line treatment in AML commonly included high cumulative doses of anthracyclines with an increasing risk of cardiotoxicity. Liposomal daunorubicin (L-DNR) is thought to be less cardiotoxic without impairment of efficacy.

METHODS

The AML-BFM REZ 97 study included two reinduction blocks with L-DNR (2 x 60 mg/m (2) n = 38, since 2/1999 3 x 60 mg/m (2) n = 31) combined with cytarabine (500 mg/m (2) 4 d). Children who achieved a second blast clearance were allocated to allogeneic stem cell transplantation either from a matched related (MRD) or a matched unrelated donor (MUD). Lack of a donor justified haploidentical SCT in early relapse (1st remission < 1 year) and autologous SCT in late relapse.

PATIENTS

Between 1/1997 and 9/2001, 69 children were enrolled in the AML-BFM 97 relapse study. The median duration of first remission was 0.9 years. Forty-one patients had a remission of less than one year, 28 of more than a year.

RESULTS

46 children (67 %) achieved a second remission, defined as clearance of blasts in bone marrow and at least a partial hematological reconstitution. Seventeen of these children are alive (12 of 25 children receiving allogeneic SCT (MFD/MUD); 1 of 8 children after haploidentical SCT; 1 of 4 patients after autologous SCT and 3 of 9 patients treated with chemotherapy only). Further three children without 2nd remission survived after MFD-SCT (n = 2) or chemotherapy (n = 1; follow-up 0.3 to 0.7 years). Duration of first remission remains a significant prognostic factor. The pharmacokinetic investigation showed a high overall AUC of 234.6 mg/l h at a dose of 60 mg/m (2), and a volume of distribution of 1.98 l/m (2), which is much lower in comparison to conventional Daunorubicin. Regarding toxicity, the combination of L-DNR and cytarabine followed by SCT was feasible in experienced centers, however, acute complications like infection or septicemia in aplasia, mucositis and GvHD were common. By contrast, no clinical relevant cardiotoxicity was seen so far, but definitive results in long-term cardiotoxicity await a longer follow-up. In conclusion, L-DNR/cytarabine treatment induced a 2nd remission in most of the children with relapsed or refractory AML. It has to be followed by allogeneic SCT which enables long-term survival.

Chemical synthesis of beta-defensins and LEAP-1/hepcidin

A large and steadily growing subfamily of antimicrobially active peptides of animals and plants is formed by the defensins, which are highly disulfide-bonded, cationic peptides with a molecular mass of about 4 kDa. The synthesis of the human beta-defensins 1 and 2 (hBD-1, hBD-2) as well as of the novel murine beta-defensins 7 and 8 (mBD-7 and mBD-8) is reported. The peptides were synthesized by solid-phase peptide synthesis using fluorenylmethoxycarbonyl chemistry. The linear products were oxidized in the presence of the cysteine/cystine redox system to the biologically active molecules. The correct disulfide connectivity of the resulting cyclic products was partly verified by mass spectrometry and sequence analysis of the fragments obtained after tryptic cleavage. In addition, the recently discovered antimicrobially active human peptide LEAP-1/hepcidin, which contains four disulfide bonds, was successfully synthesized and subsequently oxidized. For Liver-expressed anti microbial peptide (LEAP)-1/hepcidin and hBD-1, the identity of native and synthetic peptides was demonstrated by high-pressure liquid chromatography and capillary electrophoretic analysis. The general synthetic procedure is suitable to rapidly perform the total chemical synthesis of novel fully bioactive defensins, which are expected to be identified soon, as well as of structurally modified analogs.

[Telepathology--applications of an emerging technology]

Due to the development of modern telecommunication by means of high speed data transfer either by normal telephone lines or the internet we are faced with new possibilities and chances in pathology. Instead of mailing slides, today images can be transferred electronically within seconds around the world, a second opinion of a highly skilled specialist can be available within the same day or even the same hour. Beside teleconsultation, telediagnostics is the most sophisticated application of telepathology. This means the evaluation of freshly prepared cryosections obtained during surgery by a pathologist using a remotely controlled microscope in a location deprived of pathological expertise. Since the technology applied has become very reliable, problems encountered by using this technology are mainly caused by either microscopic or macroscopic sampling errors. A correct diagnosis can not be obtained if the images mailed are not containing the necessary information. The same is true for telediagnostics, if the biopsy taken for cryosection does not contain the relevant lesion, a correct diagnosis will not be possible. However, these problems are not specific for telepathology, but are encountered in routinely processed specimens as well. Thus, protocols need to be developed assuring sufficient and reproducible image sampling for teleconsultation.

[The transitory bone marrow edema syndrome of the hip]

AIM OF THE STUDY

Since MRI-studies had begun to establish the diagnosis of transitory bone marrow edema syndrome of the hip orthopedic surgeons have tried to integrate this new syndrome into the internationally accepted system of musculoskeletal diseases. Particularly, the relation to non-traumatic osteonecrosis of the femoral head and the possibilities in therapy were investigated in our clinical trial.

METHODS

Our clinical trial encompassed 106 patients suffering from the transitory bone marrow edema syndrome diagnosed in our department between the years 1985 and 2000. In order to confirm this diagnosis we used the patients' histories, their clinical courses, MRI studies, scintigraphic bone scans, intraosseal pressure measurements, phlebographies, laboratory data, and histologic specimens. One half of our collective positive for transient bone marrow edema of the hip underwent core-decompression surgery (50 patients), the other half (56 patients) was treated conservatively by analgesic medication combined with restriction of weight-bearing in the affected extremity.

RESULTS

Patients positive for transitory bone marrow edema syndrome of the hip are middle-aged individuals with a male to female predominance of 60 : 40. This group has no or only few risk factors usually associated with osteonecrosis of the femoral head. Thus, the missing alcoholic abuse is striking. All patients suffering from transitory bone marrow edema syndrome of the hip recovered completely independent of the therapy we initiated and none of them showed any signs of osteonecrosis. The one half undergoing surgical decompression of the edema by using a 4.5 mm drill experienced an markedly accelerated relief of their clinical symptoms as well as their signal changes on MRI studies. Conventional X-ray pictures and scintigraphic bone scans are not useful for early differentiation between early stages of osteonecrosis and bone marrow edemas. This also accounts for the historical measurements of intraosseal pressure determinations and phlebographies. In contrast to that, MRI studies are effective in early differentiation between osteonecrosis and bone marrow edema syndrome of the hip, especially when contrast medium (gadolinium) is administrated intravenously and fat-suppressed MRI-sequences find use. Beginning osteonecrosis of the femoral head shows a segmental loss of contrast medium, a "double line sign" interface to the intact bone marrow, and only in a few cases they are associated with a huge symptomatic edema. The histologic examination of specimens obtained from 43 patients with transitory bone marrow edema syndrome of the hip revealed no signs of osteonecrosis.

CONCLUSION

MRI studies are useful in differentiation between bone marrow edema syndrome of the hip and non-traumatic osteonecrosis of the femoral head in each stage of these two diseases. The thorough differentiation between these two diseases is of extraordinary importance for the clinical work-up of the patients as well as for scientific reasons. The course of primary bone marrow edema is benign as it results in entire recovery. The core decompression surgery offers the chance to shorten the course of the disease.