Space flight alters bacterial gene expression and virulence and reveals a role for global regulator Hfq

A comprehensive analysis of both the molecular genetic and phenotypic responses of any organism to the space flight environment has never been accomplished because of significant technological and logistical hurdles. Moreover, the effects of space flight on microbial pathogenicity and associated infectious disease risks have not been studied. The bacterial pathogen Salmonella typhimurium was grown aboard Space Shuttle mission STS-115 and compared with identical ground control cultures. Global microarray and proteomic analyses revealed that 167 transcripts and 73 proteins changed expression with the conserved RNA-binding protein Hfq identified as a likely global regulator involved in the response to this environment. Hfq involvement was confirmed with a ground-based microgravity culture model. Space flight samples exhibited enhanced virulence in a murine infection model and extracellular matrix accumulation consistent with a biofilm. Strategies to target Hfq and related regulators could potentially decrease infectious disease risks during space flight missions and provide novel therapeutic options on Earth.

[Does nicotine add to the carcinogenic strain of tobacco smoke?]

BACKGROUND

It is accepted that nicotine in tobacco smoke causes addiction via nicotinic acetylcholine receptors in the central nervous system. For a long time, the tumorigenic potential of smoking was attributed to compounds other than nicotine. However, more recently data have accumulated which suggest that nicotine may add to the cancer risk by stimulating cellular growth via non-neuronal acetylcholine receptors, by suppressing apoptosis, and by inducing angiogenesis not only in atheromatous plaques but also in tumors. In the present study the possible direct genotoxic effects of nicotine on DNA were investigated in human target cells of carcinogenesis in the upper aerodigestive tract.

PATIENTS AND METHODS

Human nasal mucosa, lymphatic tissue of the palatine tonsils, supraglottic epithelium of the larynx, and peripheral lymphocytes were exposed to rising concentrations of nicotine. DNA damage was investigated by alkaline single-cell microgel electrophoresis (Comet) assay. Cytotoxicity was assessed by trypan blue exclusion.

RESULTS

Nicotine induced dose-dependent DNA damage in all cell types at low cytotoxic concentrations that allowed viabilities well above 80%. The lowest nicotine concentrations eliciting a significant increase in DNA migration were 1 mM for tonsillar cells and 0.25 mM for all other cell types.

CONCLUSION

Nicotine induces genotoxic effects in human target cells of carcinogenesis in the upper aerodigestive tract at relevant concentrations. Thus, nicotine may contribute directly to tumor initiation resulting from smoking.

Androgen receptor and prostate cancer

Since the original observations of Huggins and Hodges that prostate cancers are androgen dependent, androgen ablation therapy has been the gold standard for the treatment of advanced prostate cancer (CaP). Androgen receptor (AR) is believed to play critical roles in the development and progression of CaP. Treatment for neoadjuvant, adjuvant and recurrent disease all center on the regulation and manipulation of the androgen pathway, in which AR plays an integral role. Recent discoveries that frequent overexpression of ETS-related proto-oncogenes may be driven by AR as a consequence of common genomic rearrangements can hold the key towards the understanding of early phases of prostate cancer. Furthermore, AR function evolves as the cell changes towards a clinically androgen depletion independent state. Comprehension of AR function, regulation and abnormalities are increasingly refined towards the understanding of the role of AR in CaP, and in therapeutic applications. Development of future therapy for CaP will be aided by improving the knowledge of dysfunctions of AR and its network in prostate cancer. This review focuses salient features of AR and on the recent advances addressing AR dysfunctions in prostate cancer.

Application of the Genotype MTBDR assay directly on sputum specimens

The Genotype MTBDR assay was tested for its capability to detect rifampicin (RMP) and isoniazid (INH) resistance (r) and susceptibility (s) directly from 42 smear-positive sputum specimens (15 RMPr/INHr, 2 RMPs/INHr and 25 RMPs/INHs Mycobacterium tuberculosis complex strains). The concordance between the MTBDR assay and conventional drug susceptibility testing was 100%.

Real-time PCR assay for improved detection of Mycobacterium tuberculosis complex in paraffin-embedded tissues

OBJECTIVE

To test the usefulness of a commercially available real-time polymerase chain reaction (PCR) kit for the detection of Mycobacterium tuberculosis complex (MTBC) in formalin-fixed, paraffin-embedded tissues.

RESULTS

The examination of 24 specimens of patients with a final diagnosis of TB shows that the real-time PCR assay exhibits a higher sensitivity (66.7%) for the detection of MTBC DNA than an alternative in-house IS6110 PCR (33.3%), whereas staining detected acid-fast bacilli in only two cases (8.3%).

CONCLUSION

The real-time PCR assay provides a highly sensitive and specific means for the detection of MTBC DNA in histopathological specimens.

High energy probe for detecting lymph node metastases with 18F-FDG in patients with head and neck cancer

AIM

of this study was to validate a newly developed high energy probe (positron emission probe, PEP) optimised for localising PET tracers in vivo.

PATIENTS AND METHODS

Physical investigations included determination of full width at half maximum (FWHM) values at a distance of 1 cm and angular resolution using different point sources. Values obtained with the new probe were compared to those of a conventional gamma probe (CGP). Additionally, PET studies were performed in 36 patients (6 women, 30 men) with proven head and neck cancer and suspected lymph node metastases (Axis, Marconi/Philips) after administering 250-320 MBq (18)F-FDG. Subsequent to PET investigations (18)F-FDG uptake in cervical regions was measured using the PEP. PEP investigations were carried out bilaterally in 5 lymph node (LN) levels (Robbins' classification of the neck). Results of probe studies were correlated with visual and semiquantitative PET evaluations, US and histological findings.

RESULTS

FWHM of the new probe was 7 mm (CGP 22 mm) at 662 keV ((137)Cs) and angular resolution resulted in 8 degrees (CGP 60 degrees ). In 29 out of 36 patients LN metastases were suspected due to ultrasound investigations. After neck dissection, histology confirmed LN metastases in 21 patients. Sensitivity (sens.) of US amounted to 95% and specificity to 40%. In 18/21 patients LN metastases were detected by PET (sens. 86%). PET scans failed to diagnose the LN status correctly in 6/36 patients (accuracy 83%). Employing the PEP probe in 20/21 patients LN metastases were identified (sens. 95%), and LN status was determined accurately in 29/36 patients (accuracy 81%). Tumour/background ratios of PEP measurement and results of semiquantitative PET analyses were comparable.

CONCLUSIONS

PEP measurement is a promising method for preoperative planning of the extent of neck dissection in patients with head and neck cancer and further for radioguided localising PET tracer accumulation during surgery.

Application of the Capilia TB assay for culture confirmation of Mycobacterium tuberculosis complex isolates

The usefulness of a low-tech rapid test for culture confirmation of Mycobacterium tuberculosis complex, Capilia TB, was tested on 172 mycobacteria-positive clinical samples. The overall sensitivity and specificity were 92.4% and 100%, respectively. In three of nine false-negative isolates a mutation in the mpb64 gene could be detected.

Hepatitis B virus vaccination of blood donors--what costs may be expected?

Although the risk of transfusion-transmitted hepatitis B virus (TT-HBV) infection is very low, it still exists. Therefore, introduction of further precautions to reduce this risk is discussed at present. However, so far no data are available about the HBV vaccination status among blood donors (BDs). We compared HBV vaccination status of apheresis donors (ADs) of a university based and whole BDs (WBDs) of a Red Cross blood donation service using a standardized questionnaire. On the basis of these data, the estimated costs over 10 years for HBV vaccination were calculated for two different strategies and compared with the costs for HBV nucleic acid amplification technology (NAT) testing. 22.3% of the WBDs and 41.2% of the ADs indicated having received at least one HBV vaccine dose. This difference was related to the different demographic structures of the two BD populations (BDPs). With regard to the primary costs for the blood donation service, HBV vaccination of BDs could be an alternative to HBV NAT testing, especially for BDPs with an already high HBV vaccination rate and a high donation frequency.

[Reduced radioiodine uptake at increased iodine intake and 131I-induced release of "cold" iodine stored in the thyroid]

AIM

The extent of urinary iodine excretion (UIE) provides information about iodine supply and release. In the present study we investigated correlations between UIE and radioiodine uptake (RIU) as well as effects of radioiodine therapy on UIE in patients with autonomous goitre.

PATIENTS, METHODS

In 197 consecutive patients with thyroid autonomy, UIE was measured twice during radioiodine test (RITe) and correlated with RIU. In 98 of these patients, thyroglobulin and thyroid volume (V) were determined prior to therapy. Individual changes in urinary iodine excretion (DeltaUIE) and TG (DeltaTG) could be investigated four weeks (4W) and six months (6M) after radioiodine therapy. Additionally, DeltaV was determined 6M after therapy. DeltaUIE, DeltaTG and DeltaV were correlated with target dose and target volume.

RESULTS

Patients with higher iodine excretion exhibited significantly lower thyroidal radioiodine uptake values. Twofold increased UIE prior to therapy decreased radioiodine uptake by 25%. Compared with pretherapeutic values, UIE and TG were significantly increased four weeks after radioiodine therapy (p < 0.001). Median values of both parameters were found to be doubled. The product of target dose and target volume was not only correlated with a decrease of thyroid volume 6M after therapy, but also with an increase of UIE and TG in the early phase after therapy.

CONCLUSIONS

It was confirmed that UIE during RITe is a measure for iodine intake and can be used to investigate the competition between stable iodine and radioiodine. The increase of UIE and TG four weeks after therapeutic administration of radioiodine can be explained by disintegrated thyroid follicles. The therapy-induced iodine release may be one important cause for the development of hyperthyroidism in some patients during the first weeks after radioiodine therapy. It may contribute to the known decrease of radioiodine uptake after preapplications of 131I in various thyroid diseases.

The Beijing genotype is a major cause of drug-resistant tuberculosis in Kazakhstan

SETTING

Nine Kazakhstan oblasts, 2001.

OBJECTIVE

To analyse the genetic relationship of drug-resistant Mycobacterium tuberculosis strains from Kazakhstan and to determine the frequency of the Beijing genotype.

DESIGN

All drug-resistant smear-positive cases identified in nine oblasts during the 2001 nationwide drug resistance survey were analysed by IS6110 fingerprinting and spoligotyping. Isolates were obtained from 150 patients (64 new and 86 retreated cases).

RESULTS

Eight cases (5.3%) of dual infection were identified. Of the remaining 142 strains, 91 (64.1%) were grouped in 18 clusters, indicating a high rate of recent transmission of resistant tuberculosis (TB). This was further confirmed by the origin of the patients as well as by the similar drug resistance patterns of the clustered strains. Accordingly, more than one third of all clustered strains were new cases. About 70% of the resistant strains belonged to the Beijing genotype, compared to only 37.5% in a control group of 40 susceptible isolates.

CONCLUSIONS

Transmission of drug-resistant strains seems to contribute to the spread of resistant TB in this high incidence region. The Beijing genotype should be seen as a major cause of drug-resistant TB in Kazakhstan and was found to be associated with drug resistance.

Interruption of agitation of platelet concentrates: effects on in vitro parameters

BACKGROUND AND OBJECTIVES

When platelet concentrates (PCs) are shipped from one centre to another, they may remain unagitated for a considerable period of time. It was therefore our aim to study the effects of interruption of agitation on the in vitro parameters of PCs stored in platelet additive solutions.

MATERIALS AND METHODS

In this multicentre study, PCs were prepared either by apheresis or from pooled buffy coats, paired to minimize donor-dependent differences, and aliquoted into 3 units with a 'low concentration' (approximately 1 x 10(9) platelets/ml; groups A, B and C) and 3 units with a 'high concentration' (approximately 2 x 10(9) platelets/ml; groups D, E and F). The final composition of the storage medium was 30% plasma and 70% additive solution in all PCs. Either PASIIIM or Composol was used as the additive solution. Agitation was interrupted for 2 days (between days 3 and 5, groups A and D), or for 4 days (between days 1 and 5, groups B and E), and continuous agitation served as the reference (groups C and F). A number of in vitro parameters were used for testing on days 1, 5 and 7.

RESULTS

On day 7, reference units C and F in PASIIIM had significantly higher pH values than the study units in PASIIIM, but all retained a pH of > 6.5 at 37 degrees C. Hypotonic shock response (HSR) results were significantly lower in the high concentration/4-day interruption group (E) than in the other groups. The low-concentration groups in PASIIIM, with agitation interrupted for either 2 days (group A) or 4 days (group B), did not have HSR values significantly different from the respective references. Study groups A, B, D and E in Composol, a solution lacking phosphate, had a pH of approximately 6.5 on day 7, which was significantly lower than that of the references and of the corresponding units in PASIIIM. The pH values were > 7.0 in reference groups C and F in Composol, not significantly different from those in PASIIIM. HSR values were also significantly lower in the Composol study groups. On the other hand, the reference Composol groups showed results similar to units in PASIIIM.

CONCLUSIONS

PCs in PASIIIM additive solution with a platelet concentration of approximately 1 x 10(9)/ml can sustain 4 days without agitation. Phosphate may be of importance in maintaining good in vitro characteristics during interruption of agitation.

[Treatment results following breast-conserving therapy in primary breast cancer]

OBJECTIVE

To evaluate mono-institutional results concerning tumor free survival, overall survival, local tumor control and rate of distant metastasis following breast-conserving therapy.

PATIENTS AND METHODS

Retrospectively, 274 breast cancer patients who were treated between 1990-1997 in our institution were analysed. The whole breast was homogeneously irradiated (2.0 Gy to 50 Gy), followed by a boost of 10-16 Gy to the tumor bed. Mean follow-up was 55 months. Overall survival, local tumor control and rate of distant metastasis were analysed.

RESULTS

Cause-specific survival at 5 years after treatment was 93 %. Within 3 to 60 months following treatment, 18 (7 %) patients suffered from ipsilateral breast recurrence. 24 (9 %) patients developed contralateral carcinoma. Survival from local recurrence (single manifestation) was 78 % at 5 years after treatment, 20 % at 7 years. Occurrence of local failures was significantly correlated to receptor status, contralateral carcinoma, distant metastasis and surgical technique and not to tumor size, margins, grading, nodal status, age or lymphangiosis. 9 % of the patients developed distant metastases, predominantly bone metastases (71 %). Survival from distant metastasis was 64 % at 5 years, 10 % at 7 years. Occurrence of distant metastasis was significantly correlated to grading, tumor size, receptor status, lymphangiosis or local recurrence.

CONCLUSION

Our institutional results show that tumor free survival, overall survival, local tumor control and distant failure rate achieved by breast conserving therapy are within the range of literature data.

Diagnostic 123I and 131I activities and radioiodine therapy. Effects on urinary iodine excretion in patients with differentiated thyroid carcinoma

AIM

Urinary iodine excretion (UIE) provides information about iodine supply and release. In the present study we investigated effects of the application of different radioiodine isotopes on UIE in patients with differentiated thyroid carcinoma (DTC).

PATIENTS, METHODS

In 91 consecutive patients with DTC UIE, measured as iodine/creatinine ratio, was determined before and after application of 123I and 131I for diagnostic or therapeutic purposes. Additionally, remnant volume (V) was determined prior to therapy. Group A consisted of 33 patients with supposed successful ablation of DTC. These patients received 370 MBq 131I for diagnostic use and served as controls. 58 patients (group B) with remnants, relapses and metastases received 370 MBq 123I for diagnostics prior to therapy with 1.5-22.2 GBq 131I. Factors influencing individual changes in urinary iodine excretion (deltaUIE) were investigated by using non-parametric tests.

RESULTS

In group A UIE did not change significantly after application of 131I. As well, UIE remained unchanged after diagnostic application of 123I in group B. In contrast, UIE increased significantly already 24 h after therapeutic application of 131I in this group. In patients with small remnants (V < 2.5 ml) a significant but only moderate increase of UIE could be observed (average increase: 47 microg I/g crea). In patients with larger remnants, with relapses or metastases increase of UIE values was significant and more pronounced.

CONCLUSIONS

It was confirmed that UIE increased significantly during radioiodine therapy in patients with DTC and radioiodine-accumulating tissue. The increase of UIE after therapeutic administration of radioiodine can be explained by the disintegrated thyroid follicles in thyroid remnants. The radioiodine-induced iodine release may be one reason for thyroid "stunning" even after application of diagnostic amounts of 131I.

Toxicological assessment of noxious inhalants

In the past centuries mankind has been exposed to various forms of air pollution not only at his occupational but also in his social environment. He mainly gets exposed with these pollutants through the respiratory organs and partially absorbs them into the body. Many of these airborne substances can be harmful for humans and some of them may account for tumorigenic effects.The following essay describes the main features of toxicological assessment of inhalative environmental and workplace xenobiotics. The essay also explains relevant characteristics and limit values of noxious compounds and gases and depicts modern testing methods. To this end, emphasis is given on methods characterizing the different stages of tumorigenic processes. Various test systems have been developed which can be used in vivo, ex vivo or in vitro. They are to a great part based on the evidence of changes in DNA or particular genes of cells. Among others they have highlighted the impact of interindividual variability on enzymatic activation of xenobiotics and on susceptibility of the host to tumor diseases.Unfortunately, for many inhalative environmental noxious agents no sufficient risk profiles have been developed. The completion of these profiles should be the goal of toxicological assessment in order to allow reasonable socioeconomic or individual-based risk reduction.

Prospective molecular epidemiological study on transmission of pulmonary Tuberculosis and Migration (MuT study) -- an interim report

INTRODUCTION

In Western Europe prevalence and incidence of tuberculosis in the indigenous population is declining and TB in migrants from high prevalence countries is becoming a major issue of TB control. Resulting changes in transmission patterns need to be investigated to adapt control strategies. The MuT (Migration and Tuberculosis) study a co-operation among federal and local public health services (ODG), the National Surveillance Center (RKI) and the University has been established in Baden-Wuerttemberg to address these issues.

OBJECTIVES

The goal of this ongoing study is to determine the transmission dynamics of TB in Baden-Wuerttemberg. Here, we present the first set of data on TB cases and their contacts and discuss strategies to overcome arising difficulties.

METHODS

Prospective data collection of culture positive pulmonary tuberculosis cases and their contacts. Analysis of (1) routine data, (2) spatial data, (3) social interaction data, (4) molecular typing data, and (5) observational data of the implementation phase.

RESULTS

The study demonstrates the capability of the study consortium to identify clusters. It provides valuable insights into current case detection and case management procedures and shows ways to improve. A set of factors has been identified that (a) facilitate and (b) discourage study participation.

CONCLUSION

Collaboration among federal and local public health services (OGD), National Surveillance Center (RKI) and the University is a promising approach to investigate and improve TB control. This model has potentials for other infectious disease control.

Prospective Molecular Epidemiological Study on Transmission of Pulmonary Tuberculosis and Migration (MuT Study)

Introduction: In Western Europe prevalence and incidence of tuberculosis in the indigenous population is declining and TB in migrants from high prevalence countries is becoming a major issue of TB control. Resulting changes in transmission patterns need to be investigated to adapt control strategies. The MuT (Migration and Tuberculosis) study a co-operation among federal and local public health services (ÖDG), the National Surveillance Center (RKI) and the University has been established in Baden-Wuerttemberg to address these issues.

Objectives: The goal of this ongoing study is to determine the transmission dynamics of TB in Baden-Wuerttemberg. Here, we present the first set of data on TB cases and their contacts and discuss strategies to overcome arising difficulties.

Methods: Prospective data collection of culture positive pulmonary tuberculosis cases and their contacts. Analysis of (1) routine data, (2) spatial data, (3) social interaction data, (4) molecular typing data, and (5) observational data of the implementation phase.

Results: The study demonstrates the capability of the study consortium to identify clusters. It provides valuable insights into current case detection and case management procedures and shows ways to improve. A set of factors has been identified that (a) facilitate and (b) discourage study participation.

Conclusion: Collaboration among federal and local public health services (ÖGD), National Surveillance Center (RKI) and the University is a promising approach to investigate and improve TB control. This model has potentials for other infectious disease control.

Storage of platelets in additive solutions: a multicentre study of the in vitro effects of potassium and magnesium

BACKGROUND AND OBJECTIVES

In a preliminary study, the presence of potassium and magnesium in a modified synthetic medium (PAS-III) was found to have a significant influence on platelet metabolism (using apheresis-derived, as well as buffy-coat-derived platelets) when compared with standard PAS-III. The differences included reduced glycolysis, as evidenced by lower consumption of glucose and lower production of lactate, but also better preservation of pH and hypotonic shock response reactivity. The results suggested that storage in modified PAS-III containing 20% plasma was comparable to storage in standard PAS-III containing 30% plasma. To confirm the preliminary results and to evaluate the effects of different preparation protocols, an international multicentre study, which included 11 different sites, was conducted.

MATERIALS AND METHODS

Platelets from 30 pools of approximately 20 buffy coat (BC) units each and 24 pooled apheresis platelet units were aliquoted for storage in plasma (reference) or synthetic medium using either a specific additive solution (PAS-III) containing 30% plasma or a modification of PAS-III containing 5.0 mm potassium and 1.5 mm magnesium (PAS-IIIM) and either 30% or 20% plasma. Units were stored at room temperature with agitation for 7 days during which in vitro testing was carried out for biochemical, haematological and functional parameters.

RESULTS

Storage of platelets in PAS-IIIM resulted in a reduction in the rate of glycolysis and better retention of pH and hypotonic shock response reactivity. Storage in PAS-IIIM containing 20% plasma appeared to result in the retention of in vitro properties, similar to those observed during storage in standard PAS-III containing 30% plasma.

CONCLUSIONS

The results of this study confirm the preliminary results. Similar results were seen with platelets prepared by BC and apheresis methods, despite differences in equipment, the preparation technique and in the final platelet contents achieved in the platelet units. Storage of platelets in PAS-IIIM should be considered to improve platelet function and allow plasma reduction to 20%.

[Uncommon mycobacterial infections in domestic and zoo animals: four cases with special emphasis on pathology]

Infections caused by classical tubercle bacilli are rare during the last years. Nevertheless, diseases caused by other mycobacteria have to be considered clinically and in diagnostic pathology especially in cases of immunosuppression and due to their potential zoonosis risk. An infection by mycobacteria was diagnosed in four animals (Mayotte Maki, Blue-headed Parrot, Patagonian sealion, Beagle) necropsied between 1995 and 2002 in the Institute of Veterinary-Pathology of the University of Leipzig. The Maki, the blue-headed parrot and the dog showed a disseminated character of the disease caused by Mycobacterium genavense (monkey and bird) resp. Mycobacterium avium (dog), while an open chronical tuberculosis of the lungs due to a pathogenic member of Mycobacterium tuberculosis complex was observed in the seal. All these bacteria are potential causes of zoonoses. So, if granulomatous or disseminated histiocytic alterations are detected in diagnostic pathology, mycobacterial infections should always be included in differential diagnoses and require careful aetiological investigations by histopathological and bacteriological methods.

Post-mortem diagnosis and age estimation of infants' fractures

Detection and dating of infants' fractures plays an important role in the diagnosis of the battered child syndrome. Under this aspect three cases of infants with multiple fractures of different ages due to child abuse were evaluated post-mortem. Radiological findings were compared with the autopsy results, followed by contact radiography and histopathological assessment. Out of a total of 44 osseous lesions, 27 fractures were diagnosed by post-mortem skeletal survey, additionally 5 recent rib fractures were suspected, 4 of which were confirmed histologically and all were located paravertebrally. The fractures not detected radiologically were mostly recent rib fractures diagnosed or suspected at autopsy or by contact radiography and confirmed histologically. The histological investigation allowed a more precise dating of the fractures, particularly with reference to the early stages of fracture healing. Microscopic signs of fracture healing processes, such as periosteal thickening, osteoid production and calcification of soft callus tissue, can be detected earlier and quantified more accurately. In advanced stages of healing the osseous apposition rate can be measured semiquantitatively up to a certain extent. A scheme involving a careful external investigation, skeletal survey, autopsy, contact radiography and histology has been proven useful for diagnosing and dating infants' fractures.

Physiological role of AMP-activated protein kinase (AMPK): insights from knockout mouse models

AMP-activated protein kinase (AMPK) is viewed as a fuel sensor for glucose and lipid metabolism. To understand better the physiological role of the catalytic AMPK subunit isoforms, we generated two knockout mouse models with the alpha1 (AMPK alpha 1(-/-)) and alpha 2 (AMPK alpha 2(-/-)) catalytic subunit genes deleted. No defect in glucose homoeostasis was observed in AMPK alpha 1(-/-) mice. On the other hand, AMPK alpha 2(-/-) mice presented high plasma glucose levels and low plasma insulin concentrations in the fed period and during the glucose tolerance test. Nevertheless, in isolated AMPK alpha 2(-/-) pancreatic islets, glucose-stimulated insulin secretion was not affected. Surprisingly, AMPK alpha 2(-/-) mice were insulin-resistant and had reduced muscle glycogen synthesis as assessed in vivo by the hyperinsulinaemic euglycaemic clamp procedure. Reduction of insulin sensitivity and glycogen synthesis were not dependent on the lack of AMPK in skeletal muscle, since mice expressing a dominant inhibitory mutant of AMPK in skeletal muscle were not affected and since insulin-stimulated glucose transport in incubated muscles in vitro was normal in AMPK alpha 2(-/-) muscles. Furthermore, AMPK alpha 2(-/-) mice have a higher sympathetic tone, as shown by increased catecholamine urinary excretion. Increased adrenergic tone could explain both decreased insulin secretion and insulin resistance observed in vivo in AMPK alpha 2(-/-) mice. We suggest that the alpha2 catalytic subunit of AMPK plays a major role as a fuel sensor by modulating the activity of the autonomous nervous system in vivo.

High-pressure Raman study of debundled single-walled carbon nanotubes

We report the pressure dependence for the radial (omega R) and tangential (omega T) band frequencies in debundled single-walled carbon nanotubes (SWNTs) derived from laser-synthesized SWNT bundles. As previously described, a chemical procedure was used to prepare debundled SWNTs from as-prepared, large SWNT bundles. The normalized pressure coefficient for omega R in the debundled sample was compared with the corresponding value in the bundled sample to quantify the strength of van der Waals interactions between tubes in these nanotube materials. Furthermore, the pressure dependences for the radial (omega R) and tangential (omega T) band frequencies in debundled tubes were also compared with corresponding dependences predicted for isolated SWNTs, obtained with generalized tight binding molecular dynamic (GTBMD) simulations described in our previous work. The results presented here collectively suggest that the van der Waals interaction is still strong in the debundled sample studied here, which contained predominantly small bundles of SWNTs rather than isolated tubes.

Nitrosation of dietary myosmine as risk factor of human cancer

The tobacco alkaloid myosmine was detected in nut and nut products [J. Agric. Food Chem. 46 (1998) 2703]. Upon nitrosation, myosmine yields 4-hydroxy-1-(3-pyridyl)-1-butanone (HPB) and N-nitrosonornicotine (NNN) [J. Agric. Food Chem. 48 (2001) 392]. NNN is a strong oesophageal carcinogen in rats. Metabolic activation of NNN leads to formation of DNA and protein adducts which release HPB upon hydrolysis. In the present study the time, pH and dose-dependent nitrosation of myosmine and its covalent binding to DNA was investigated. [5-(3)H]myosmine was incubated with nitrite for 1-24 h in buffer solutions adjusted to pH 1-6. At pH 2-4 myosmine was easily nitrosated and gave rise to two major products, HPB and NNN, and five minor not yet identified products. Maximal formation was achieved for HPB at pH 2 after 8 h (72% of total radioactivity) and for NNN at pH 3 after 8 h (16%). For DNA binding studies labeled myosmine was incubated under nitrosation conditions with calf thymus DNA. Within 3 h up to 0.1% of the radioactivity was covalently bound to DNA. Endogenous nitrosation of myosmine, present in nuts and other dietary components could constitute a significant risk factor for tumours in the upper intestinal tract such as oesophageal adenocarcinoma, which are unrelated to tobacco smoking and alcohol abuse.

Ion beam treatment of titanium surfaces for enhancing deposition of hydroxyapatite from solution

Surface coating with hydroxyapatite (HA) is a common way to improve the osseointegration of orthopaedic and dental titanium (Ti)-based materials. The main problems with current techniques are changes in composition during heating and poor adhesion to the surface. An alternative method is deposition of HA onto an activated surface out of a solution. The present work studies the surface treatment involving ion implantation of Na into Ti to induce a modification in chemistry and morphology, showing sodium titanate (Na(2)TiO(3)) incorporated within the surface layer with concentration, depth distribution, and morphology depending on the parameters of the ion implantation. Such ion-implanted Ti surfaces actively induce heterogeneous precipitation of HA from a simulated body fluid containing physiological concentrations of calcium and phosphate ions. This is compared with the activation by NaOH etching. The growth of bone forming cells on the pure Na implanted surface is oriented without an increased bone formation. Cell growth on the NaOH etched surface is reduced. After deposition of HA on both surfaces cell the growth pattern was improved.

Mycobacterium tuberculosis gene-amplification in breath condensate of patients with lung tuberculosis

The applicability of Mycobacterium tuberculosis-gene-amplification test (NAT) in breath condensate (BC) was examined in lung tuberculosis (TB). Ten patients with bacteriologically confirmed lung TB have been examined by ligase chain reaction (LCx). In BC the NAT were negative in all patients as well as the examination of acid fast smears and of solid phase or liquid media cultures were. This indicates that the use of NAT in BC can not replace or complement sputum or materials obtained invasively in patients with lung TB.

Remission of cutaneous Mycobacterium haemophilum infection as a result of antiretroviral therapy in a Human Immunodeficiency Virus--infected patient

We describe the first Mycobacterium haemophilum infection that occurred in a patient with human immunodeficiency virus in Germany and report 7 newly diagnosed cases of M. haemophilum infection. In the former case, a local M. haemophilum skin infection resolved as a result of successful antiretroviral therapy only; however, that clinical outcome may not be possible for more invasive forms of the disease.

Solution deposition of hydroxyapatite on titanium pretreated with a sodium ion implantation

Titanium surfaces were treated by exposing them to a beam of sodium ions. Sodium titanate was shown to be incorporated within the oxidic titanium surface. The ion-implanted surfaces were examined for their reactivity by immersion in a simulated body fluid, which showed the formation of surface-bound hydroxyapatite. The surface was characterized by X-ray diffraction, Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy, and optical and electron microscopy. The surface hydroxyl concentration was determined using the nuclear reaction (1)H((15)N, alpha gamma)(12)C. Surface-related parameters that may affect hydroxyapatite nucleation are discussed in terms of the electrical double layer.

The effect of a 2-h exposure to cigarette smoke on the metabolic activation of the tobacco-specific nitrosamine 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone in A/J mice

4-(Methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK), a tobacco-specific nitrosamine, induces lung adenomas in A/J mice following a single intraperitoneal (i.p.) injection. However, inhalation of mainstream cigarette smoke does not induce or promote NNK-induced lung tumors in this mouse strain purported to be sensitive to chemically-induced lung tumorigenesis. The critical events for NNK-induced lung tumorigenesis in A/J mice is thought to involve O(6)-methylguanine (O(6)MeG) adduct formation, GC-->AT transitional mispairing, and activation of the K-ras proto-oncogene. The objective of this study was to test the hypothesis that a smoke-induced shift in NNK metabolism led to the observed decrease in O(6)MeG adducts in the lung and liver of A/J mice co-administered NNK with a concomitant 2-h exposure to cigarette smoke as observed in previous studies. Following 2 h nose-only exposure to mainstream cigarette smoke (600 mg total suspended particulates/m(3) of air), mice (n=12) were administered 7.5 micromol NNK (10 microCi [5-3H]NNK) by i.p. injection. A control group of 12 mice was sham-exposed to HEPA-filtered air for 2 h prior to i.p. administration of 7.5 micromol NNK (10 microCi [5-3H]NNK). Exposure to mainstream cigarette smoke had no effect on total excretion of NNK metabolites in 24 h urine; however, the metabolite pattern was significantly changed. Mice exposed to mainstream cigarette smoke excreted 25% more 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanol (NNAL) than control mice, a statistically significant increase (P<0.0001). Cigarette smoke exposure significantly reduced alpha-hydroxylation of NNK to potential methylating species; this is based on the 15% reduction in excretion of the 4-(3-pyridyl)-4-hydroxybutanoic acid and 42% reduction in excretion of 4-(3-pyridyl)-4-oxobutanoic acid versus control. Detoxication of NNK and NNAL by pyridine-N-oxidation, and glucuronidation of NNAL were not significantly different in the two groups of mice. The observed reduction in alpha-hydroxylation of NNK to potential methylating species in mainstream cigarette smoke-exposed A/J mice provides further mechanistic support for earlier studies demonstrating that concurrent inhalation of mainstream cigarette smoke results in a significant reduction of NNK-induced O(6)MeG adduct formation in lung and liver of A/J mice compared to mice treated only with NNK.

Use of serum creatinine to predict pathologic stage and recurrence among radical prostatectomy patients

OBJECTIVES

To assess serum creatinine as a putative marker for staging/prognosis in localized prostate cancer. Although clinical stage, tumor grade, serum prostate-specific antigen (PSA), and tumor volume assessment by biopsy positivity are established prognostic markers in prostate cancer, the need for additional serum markers is clear. In a prior neural network analysis by our group, serum creatinine appeared to improve staging and prognosis. Even though serum creatinine is one of the most common blood tests used by practicing urologists, it has not been tested rigorously as a potential staging/prognosis marker in localized prostate cancer.

METHODS

The data on 409 patients who underwent radical prostatectomy at the Walter Reed Army Medical Center between 1990 and 1996 were analyzed. Logistic regression analysis was used to evaluate the ability of serum creatinine to predict the pathologic stage. The ability of creatinine to predict PSA recurrence was also assessed using Cox regression analysis. In multivariable analyses, creatinine was assessed while simultaneously controlling for race, age, prostate weight, clinical stage, Gleason (World Health Organization) grade, prostatism history, treatment of benign prostatic hyperplasia, and pretreatment PSA level.

RESULTS

Creatinine ranged from 0.1 to 2.3 mg/dL (mean and median 1.1 mg/dL). The relationship of creatinine to pathologic stage was significant (P = 0.050). As the level of creatinine increased, the proportion of patients with extraprostatic disease generally decreased. In multivariable logistic regression analysis, creatinine was not a significant predictor (P = 0.270). The relationship of the creatinine level to PSA recurrence was not significant in the univariate or multivariable analysis.

CONCLUSIONS

Creatinine did not provide independent information for predicting pathologic stage or disease recurrence in patients with early prostate cancer.

Creating a high-resolution spatial/symbolic model of the inner organs based on the Visible Human

Computerized three-dimensional models of the human body, based on the Visible Human Project of the National Library of Medicine, so far do not reflect the rich anatomical detail of the original cross-sectional images. In this paper, a spatial/symbolic model of the inner organs is developed, which is based on more than 1000 cryosections and congruent fresh and frozen CT images of the male Visible Human. The spatial description is created using color-space segmentation, graphic modeling, and a matched volume visualization with subvoxel resolution. It is linked to a symbolic knowledge base, providing an ontology of anatomical terms. With over 650 three-dimensional anatomical constituents, this model offers an unsurpassed photorealistic presentation and level of detail. A three-dimensional atlas of anatomy and radiology based on this model is available as a PC-based program.

Haemoglobin adducts from aromatic amines in children in relation to area of residence and exposure to environmental tobacco smoke

OBJECTIVE

The influence of area of residence on haemoglobin (Hb) adducts of 4-aminobiphenyl (4-ABP), o-, m-, p-toluidine and o-anisidine was investigated in children from three different-sized Bavarian cities - Munich, Augsburg and Eichstätt, with 1,300,000, 250,000 and 13,000 inhabitants, respectively--and was compared with that of exposure to environmental tobacco smoke (ETS).

METHODS

Blood samples from Munich (n = 34) and Eichstätt (n = 64) were from children attending the Paediatric Clinic of the Technical University of Munich (TUM) or a practice in Eichstätt, respectively. Blood samples (n = 126) together with urine samples (n = 88) were collected from Augsburg children during school medical examination. Personal data including possible sources of ETS exposure were obtained at the interview. Hb adduct levels were analysed by a gas chromatographic method, using mass spectrometry with selected-ion monitoring. Urinary cotinine was determined by radioimmunoassay.

RESULTS

4-ABP Hb adduct levels in children from Munich were 1.5 and 1.2 times higher than those in children from Eichstätt and Augsburg (P < 0.001). Children from Munich also had significantly higher Hb adduct levels of monocyclic aromatic amines than did children from Eichstätt and, except for o-toluidine, children from Augsburg (P < 0.005). Compared with children from Eichstätt, children from Augsburg had higher Hb adduct levels of 4-ABP, o- and m-toluidine (P < 0.01) but not p-toluidine and o-anisidine. In a multivariate analysis, gender, age and body mass index had no consistent influence on Hb adducts. ETS exposure resulted in a slight, nonsignificant increase in 4-ABP Hb adduct levels. In contrast, adduct levels from monocyclic aromatic amines were consistently decreased in ETS-exposed children (significant for o- and m-toluidine, P<0.05).

CONCLUSIONS

Hb adducts from aromatic amines in children were strongly influenced by site of residence, whereas ETS exposure did not significantly increase the adduct levels.JECT

Exploring the visible human's inner organs with the VOXEL-MAN 3D navigator

Improved rendering and segmentation techniques lead to a new quality of 3D reconstructions of the Visible Human. Using these we have implemented an interactive atlas of anatomy and radiology of the inner organs.

Impact of plasmapheresis on platelet hemostatic capacity in healthy voluntary blood donors detected by the platelet function analyzer PFA-100

Previous flow cytometry studies showed that platelet activation may occur during cytapheresis, cardiopulmonary bypass and hemodialysis. The aim of this pilot study was to determine if the impact of plasmapheresis leads to alterations in platelet hemostatic capacity. Plasmapheresis was carried out in 30 volunteers using an Autopherese C (Baxter) and an MCS3p (Haemonetics). Blood samples were collected and analyzed immediately before and after plasmapheresis. As a result of the plasmapheresis on the Autopherese C, the mean closure time (CT) for collagen/epinephrine (Col/Epi) increased from 118.2 +/- 25.1 to 149.9 +/- 35.0 s and from 88.7 +/- 16.9 to 98.5 +/- 26.3 s for collagen/ADP (Col/ADP), respectively. Seven subjects showed impaired CTs after plasmapheresis for Col/Epi. For Col/ADP, five subjects showed impaired CTs after apheresis. Statistical analysis (McNemar test) showed a significant difference before and after apheresis for Col/Epi (P = 0.024) but not for Col/ADP (P = 0.088). Similar results were shown for plasmapheresis carried out with the MCS3p. These findings show that plasmapheresis can cause an impairment of platelet function in healthy volunteers as measured by the PFA-100, an effect of so far unknown clinical significance.