Predictive preoperative clinical score for patients with liver-only oligometastatic colorectal cancer

Background

Resection of liver metastases from colorectal cancer (CRC) in the oligometastatic stage improves survival and is a potentially curative treatment. Thus, predictive scores that reliably identify those patients who especially benefit from surgery are essential.

Patients and methods

In this multicenter analysis, 512 patients had undergone surgery for liver metastases from CRC. We investigated distinct cancer-specific risk factors that are routinely available in clinical practice and developed a predictive preoperative score using a training cohort (TC), which was thereafter tested in a validation cohort (VC).

Results

Inflammatory response to the tumor, a right-sided primary tumor, multiple liver metastases, and node-positive primary tumor were significant adverse variables for overall survival (OS). Patients were stratified in five groups according to the cumulative score given by the presence of these risk factors. Median OS for patients without risk factors was 133.8 months [95% confidence interval (CI) 81.2-not reached (nr)] in the TC and was not reached in the VC. OS decreased significantly for each subsequent group with increasing number of risk factors. Median OS was significantly shorter (P < 0.0001) for patients presenting all four risk factors: 14.3 months (95% CI 10.5 months-nr) in the TC and 16.6 months (95% CI 14.6 months-nr) in the VC.

Conclusions

Including easily obtainable variables, this preoperative score identifies oligometastatic CRC patients with prolonged survival rates that may be cured, and harbors potential to be implemented in daily clinical practice.

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We identified four variables of adverse outcome for patients treated with surgical resection of liver metastases from CRC.

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Adverse variables were inflammatory response to the tumor, multiple metastases, right-sided primary tumor, node-positive primary tumor.

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We developed a preoperative clinical score according to the number of risk factors present.

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Using easily obtainable variables, this score identified patients with oligometastatic CRC with good prognosis.

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Patients without risk factors should strongly be considered for surgical resection of their metastases.

Survival of colorectal cancer: the role of contextual, individual and tumour-specific characteristics

Background

Colorectal cancer (CRC) is the second most common cancer in women and the third most common cancer in men in Germany. One in two people suffering from CRC dies within five years after diagnosis. The aim of our ongoing research project is to investigate the interaction of contextual, individual and tumour-specific characteristics and their effect on CRC survival in Bavaria.

Methods

A total of 124,958 incident cases of CRC (ICD-10 C18-C20) from the Bavarian Cancer Registry are linked with data on area deprivation based on the Bavarian Index of Multiple Deprivation (BIMD). We include all years with a CRC-specific case completeness of 90% or more, i.e. 2004 to 2018. We calculate Kaplan-Meier curves as well as mixed proportional hazards models including non-linear effects. Our modelling strategy starts from a baseline model with random effects at district, municipality, and individual level, which we continuously extend to include regional (deprivation), individual (age at diagnosis, sex) as well as tumour-specific variables (tumour site, grading, cancer stage, histological subtype, diagnosis of multiple primary tumours).

Results

Preliminary results show significant random effects at district and municipality level as well as a negative impact of deprivation on CRC survival for all sites. Individual as well as tumour-specific characteristics, such as age, grading, and cancer stage, demonstrate the strongest effects on CRC survival and partly explain survival differences according to area level (districts, municipalities), and level of deprivation. The effects of individual as well as tumour-specific characteristics vary between districts and municipalities in Bavaria depending on their level of area deprivation.

Conclusions

Contextual, individual and tumour-specific characteristics have an impact on CRC survival. Future studies may also include health services characteristics in CRC survival analysis.

Key messages

CRC survival is inversely associated with area deprivation in Bavaria. The effects of individual and tumour-specific characteristics, e.g. age and cancer stage, increase with the level of deprivation.

Einfluss von Hitzebelastung auf Thermoregulation und Fruchtbarkeitsleistung bei geschorenen und ungeschorenen männlichen Lamas (Lama glama)

Gegenstand und Ziel: Besitzer von Neuweltkameliden messen einem ungestörten Reproduktionsgeschehen ihrer Tiere vor allem aus wirtschaftlichem Interesse hohe Bedeutung zu. Bei Lamahengsten besteht aufgrund der anatomischen Besonderheiten die Gefahr, dass sie auf Hitzebelastungen mit reduzierten Fruchtbarkeitsleistungen reagieren. In diesem Zusammenhang wirkt sich die zeitige Schur vermutlich besonders aus. Material und Methoden: Zehn fertile Lamahengste (Lama glama), fünf geschorene und fünf ungeschorene, wurden unter kontrollierten Wärmebedingungen (4 Wochen bei 30 °C, anschließend Erholungsphase bei 20 °C) gehalten und Merkmale der Thermoregulation (u. a. Infrarotthermographie) und des Reproduktionsgeschehens (n = 4) über einen Zeitraum von 13 Wochen erfasst und ausgewertet. Ergebnisse: Die Tiere konnten während der gesamten Versuchsdauer ihre Körperinnentemperatur im physiologischen Bereich halten, was mit einer signifikant gesteigerten Atemfrequenz einherging. Darin scheint ein wesentlicher Mechanismus der Thermoregulation zu bestehen, da eine Wärmeabgabe durch Schwitzen nur an den schwach bis unbewollten Körperstellen (thermale Fenster) möglich ist. Während der Hitzephase nahmen Ejakulatvolumen und Spermiendichte ab. Schlussfolgerung und klinische Relevanz: Die effektive Thermoregulation durch Wärmeabgabe erfolgt bei Lamas überwiegend im Bereich der thermalen Fenster. An den Hoden ist bei länger anhaltender höherer Umgebungstemperatur die Thermoregulierung so stark eingeschränkt, dass es zu Fertilitätsverlusten kommt.

Survival benefit of pelvic and paraaortic lymphadenectomy in high-grade endometrial carcinoma: a retrospective population-based cohort analysis

OBJECTIVE

The standard therapy for high-grade endometrial cancer is surgery but the therapeutic effects of pelvic and paraaortic lymph node dissection (LND) are poorly investigated. In this study, we retrospectively evaluated overall survival, recurrence rates and recurrence-free survival among patients with high-grade type I and II endometrial carcinoma who underwent LND.

METHODS

This study included 284 patients who are recorded in the German Tumor Centre Regensburg form 1998 to 2015 and were selected by cancer grading, the absence of secondary tumors, primary surgery including hysterectomy and available follow-up. 244 of the 284 patients in this cohort were unequivocally classified as R0 after resection.

RESULTS

A significantly increased overall survival was observed for systematic LND of 25 or more paraaortic and pelvic lymph nodes versus patients who did not undergo such intervention (p < 0.001) or had elective LND of 1-24 lymph nodes both in univariable (p = 0.016) and multivariable (p = 0.014) analysis. A similar observation was made for recurrence-free survival of patients in the cohort who underwent complete tumor resection (R0). In addition, a reduced cumulative recurrence rate was observed for patients with systematic LND.

CONCLUSIONS

Our study provides evidence that the systematic removal of 25 or more pelvic and paraaortic lymph nodes reduces the recurrence rate and that it is beneficial for the long-term overall and recurrence-free survival of patients with high-grade endometrial cancer.

Comparative selective retention of particle size classes in the gastrointestinal tract of ponies and goats

There is a discrepancy in the literature on potential digesta separation mechanisms in horses, with both a selective retention of fine and of large particles postulated in different publications. To assess the net effect of such mechanisms, we fed ponies on a hay-only diet a pulse dose of whole (unchopped) marked hay together with a solute marker, collected faeces on a regular basis, measured marker concentrations in whole faeces and in their large (2.0-16 mm), medium (0.5-1.0 mm) and small (0.063-0.25 mm) particle fraction, and calculated the corresponding mean retention times (MRTs). For comparison, the same experiment was performed in goats. In goats, as expected, MRT_solute (35 hr) was significantly shorter than MRT_particle (51 hr); only a very small fraction of particle marker was excreted as large particles (2%); and the MRT of these large particles was significantly shorter than that of small particles (with a relevant difference of 8.6 hr), indicating that those few large particles that escape the rumen do so mostly soon after ingestion. In ponies, MRT_solute (24 hr) did not differ from MRT_particle (24 hr); a higher fraction of particle marker was excreted as large particles (5%); and the MRT of these large particles was longer than that of small particles (but with a non-relevant difference of less than 1 hr). These results indicate that no relevant net separation of digesta phases occurs in horses and that selective particle retention mechanisms in the large intestine are unlikely to represent important characteristics of the horse's digestive physiology.

Effects of morcellation on long-term outcomes in patients with uterine leiomyosarcoma

OBJECTIVES

Clinical long-term outcomes of women with uterine leiomyosarcoma (ULMS) with different types of hysterectomy (open abdominal, vaginal, laparoscopic and switch from laparoscopic to open abdominal) were compared according to morcellation and other factors.

MATERIALS

The clinical cancer registry Regensburg (Germany) registered 64 patients between 2004 and 2013 with ULMS. A retrospective cohort analysis was performed using the Kaplan-Meier method to estimate 5-year overall survival (OAS), recurrence-free survival (RFS) and recurrence rates. To compare surgery with or without morcellation log rank test was used. To adjust for age, FIGO stage, grading and other factors multivariable Cox regression models were applied to estimate hazard ratios (HR).

RESULTS

In the cohort of 64 patients 15 underwent morcellation, preferably during laparoscopic surgery. Although numbers were small we performed analysis for OAS and RFS. Median OAS for morcellation was 10.6 vs. 6.4 years for non morcellation. 5y-OAS was 76.0 % for morcellation compared to 54.8 % in patients without morcellation (p = 0.115). Cox regression models rendered an unadjusted (univariable) HR 0.428 for morcellation vs. non-morcellation (p = 0.125) and an adjusted (multivariable) HR 0.644 (p = 0.406). 5y-RFR was 64.0 % compared to 42.8 % in patients without morcellation (p = 0.104; unadjusted HR 0.484, p = 0.111; adjusted HR 0.607, p = 0.306).

CONCLUSION

In general, the prognosis of patients with ULMS is poor. In our cohort, women who underwent hysterectomy with morcellation had a better cumulative OAS and RFS than women without morcellation. Although we adjusted for differences between women with and without morcellation regarding age, grading and stage, there were no statistically significant differences between the groups.

Comprehensive Molecular Characterization of Papillary Renal-Cell Carcinoma

BACKGROUND

Papillary renal-cell carcinoma, which accounts for 15 to 20% of renal-cell carcinomas, is a heterogeneous disease that consists of various types of renal cancer, including tumors with indolent, multifocal presentation and solitary tumors with an aggressive, highly lethal phenotype. Little is known about the genetic basis of sporadic papillary renal-cell carcinoma, and no effective forms of therapy for advanced disease exist.

METHODS

We performed comprehensive molecular characterization of 161 primary papillary renal-cell carcinomas, using whole-exome sequencing, copy-number analysis, messenger RNA and microRNA sequencing, DNA-methylation analysis, and proteomic analysis.

RESULTS

Type 1 and type 2 papillary renal-cell carcinomas were shown to be different types of renal cancer characterized by specific genetic alterations, with type 2 further classified into three individual subgroups on the basis of molecular differences associated with patient survival. Type 1 tumors were associated with MET alterations, whereas type 2 tumors were characterized by CDKN2A silencing, SETD2 mutations, TFE3 fusions, and increased expression of the NRF2-antioxidant response element (ARE) pathway. A CpG island methylator phenotype (CIMP) was observed in a distinct subgroup of type 2 papillary renal-cell carcinomas that was characterized by poor survival and mutation of the gene encoding fumarate hydratase (FH).

CONCLUSIONS

Type 1 and type 2 papillary renal-cell carcinomas were shown to be clinically and biologically distinct. Alterations in the MET pathway were associated with type 1, and activation of the NRF2-ARE pathway was associated with type 2; CDKN2A loss and CIMP in type 2 conveyed a poor prognosis. Furthermore, type 2 papillary renal-cell carcinoma consisted of at least three subtypes based on molecular and phenotypic features. (Funded by the National Institutes of Health.).

Short communication: milk output in llamas (Lama glama) in relation to energy intake and water turnover measured by an isotope dilution technique

Despite the fact that llamas have become increasingly popular as companion and farm animals in both Europe and North America, scientific knowledge on their nutrient requirements is scarce. Compared with other livestock species, relatively little is known especially about the nutrient and energy requirements for lactating llamas. Therefore, we aimed to measure milk output in llama dams using an isotope dilution technique and relate it to energy intakes at different stages of lactation. We also validated the dilution technique by measuring total water turnover (TWT) directly and comparing it with values estimated by the isotope dilution technique. Our study involved 5 lactating llama dams and their suckling young. Milk output and TWT were measured at 4 stages of lactation (wk 3, 10, 18, and 26 postpartum). The method involved the application of the stable hydrogen isotope deuterium ((2)H) to the lactating dam. Drinking water intake and TWT decreased significantly with lactation stage, whether estimated by the isotope dilution technique or calculated from drinking water and water ingested from feeds. In contrast, lactation stage had no effect on dry matter intake, metabolizable energy (ME) intake, or the milk water fraction (i.e., the ratio between milk water excreted and TWT). The ratios between TWT measured and TWT estimated (by isotope dilution) did not differ with lactation stage and were close to 100% in all measurement weeks, indicating that the D(2)O dilution technique estimated TWT with high accuracy and only small variations. Calculating the required ME intakes for lactation from milk output data and gross energy content of milk revealed that, with increasing lactation stage, ME requirements per day for lactation decreased but remained constant per kilogram of milk output. Total measured ME intakes at different stages of lactation were similar to calculated ME intakes from published recommendation models for llamas.

Effect of shearing on water turnover and thermobiological variables in German Blackhead mutton sheep

Current equations for estimating water requirements in sheep do not differentiate between shorn and unshorn sheep. Furthermore, the effect of shearing on thermoregulative responses in sheep has not been adequately studied under temperate environmental conditions. Therefore, the present study was conducted to investigate the effect of wool coverage on water turnover in relation to thermoregulation in sheep by using the deuterium dilution technique to predict total water intake before and after shearing. Physiological responses, such as water turnover, surface temperature, and rectal temperature, as well as drinking behavior of sheep were also evaluated. Fourteen nonlactating German Blackhead mutton ewes were randomly allocated into 2 groups: a control group (n = 7) that was already shorn, and a treatment group (n = 7) that was left unshorn (wool length: 10.6 ± 1.2 cm). Individual feed and water intakes were recorded throughout the experiment (d 1 to 71). Two weeks after measurements commenced (d 15), treatment sheep were shorn. Water intake was estimated twice for 2 consecutive weeks by using deuterium dilution techniques (d 1 to 15 and d 57 to 71). Ambient temperature (T(a)), relative humidity, and respiratory rate were measured daily, whereas BW, rectal and animal surface temperatures (using infrared thermography), and wool length were measured weekly. In the first 2 wk, when treatment sheep were unshorn, treatment and control ewes differed (P < 0.05) in DMI (52 ± 4 vs. 59 ± 4 g·kg(-0.75)·d(-1)), water intake (165 ± 17 vs. 134 ± 18 g·kg(-0.75)·d(-1)), respiratory rate (66 ± 5 vs. 31 ± 4 breath/min), rectal temperature (39.3 ± 0.2 vs. 38.8 ± 0.1°C), and surface temperatures (body side: 19.3 ± 0.3 vs. 24.5 ± 0.6°C; leg: 25.8 ± 2.4 vs. 27.4 ± 1.6°C). However, after shearing, these differences partly disappeared. The same trend in water intake between groups was confirmed using the isotope dilution technique. We found a significant relationship between T(a) and water intake, respiratory rate, and body surface temperatures. Even under temperate conditions (T(a) < 28°C), shearing significantly reduced core body temperature, water intake, and respiratory rate in German Blackhead mutton sheep, thus indicating heat stress in fleeced animals, which should be considered when determining the optimal shearing time in sheep as well as when estimating water requirements.

[Social gradient of PSA screening? 8 years follow up from the cancer registry of the tumor center in Regensburg]

BACKGROUND

Prostate cancer is the most frequent male cancer. In Germany most tumors are detected by PSA testing. Data on the long-term survival of patients with localized early prostate carcinoma are insufficient. We examined the relative survival of the patients with organ-defined prostate cancer (TNM T1-2N0M0, UICC I-II) compared to the standardized age-adjusted rates of the normal male population.

METHODS

Epidemiological and clinical data from 4,124 patients with prostate cancer diagnosed from 1998 to 2007 were extracted from the cancer registry of the tumor center in Regensburg; 2,087 patients suffered from localized early cancer. Kaplan-Meier analysis was used to estimate the overall survival rates in the patient cohorts irrespective of primary cancer therapy. These rates were adjusted for the expected survival rates in a comparable set of individuals from the general population.

RESULTS

Eight years after diagnosis, patients with stage I and II localized prostate cancer had an approximately 10% relative increase in survival compared with the normal male population. This relative increase in survival was already observed 3 years after diagnosis.

CONCLUSION

Patients with stage I-II localized prostate cancer have improved survival compared with the normal male population. This finding cannot be explained solely by the administration of prostate cancer treatments, which do not affect survival until 8-10 years after treatment, suggesting that men who participate in PSA testing may have a better overall health status. Another hypothesis may be a social gradient of PSA testing in Germany.

Intermediate high index layer for laser mode tuning in organic semiconductor lasers

We modified the optical properties of organic semiconductor distributed feedback lasers by introducing a high refractive index layer consisting of tantalum pentoxide between the substrate and the active material layer. A thin film of tris-(8-hydroxyquinoline) aluminium doped with the laser dye 4-dicyanomethylene-2-methyl-6-(p-dimethylamino-styryl)-4H-pyran was used as the active layer. By varying the intermediate layer thickness we could change the effective refractive index of the guided laser mode and thus the laser wavelength. With this technique we were able to tune the laser emission range between 613 nm and 667 nm. For high index layer thicknesses higher than 40 nm the laser operated on the TE(1)-mode rather than the fundamental TE(0)-mode.

Changes in Llama (Lama glama) milk composition during lactation

Milk samples were collected weekly from 10 llamas during the first 27 wk after parturition under controlled stable conditions. Mean values for the concentrations of the major milk components across the lactation period were 4.70% fat, 4.23% protein, 5.93% lactose, 15.61% dry matter, and 22.62 mg/dL of milk urea N. All constituents were affected by the stage of lactation. There was an increase in fat to protein ratio as protein concentration declined and fat concentration increased. Fat, protein, and lactose concentrations changed during the transition from colostrum to milk. In the first month postpartum, fat concentration remained constant, protein decreased, and lactose increased. Starting with wk 5 postpartum, fat and protein increased and lactose decreased until the end of lactation. Among the major constituents fat had the highest variation. The mean gross energy concentration of milk was 3.88 kJ/g and showed a similar course as protein. Fat contributed 48.0%, protein 26.3%, and lactose 25.7% to the gross energy in the milk. Milk urea N values were higher than those found in ruminants and increased with stage of lactation, whereas the pH decreased. The analyzed milk components were not affected by the lactation number of the animal, except milk urea N. Somatic cell counts indicated the absence of mastitis and revealed that the average somatic cell count of uninfected llamas is lower than in animals usually used for milk production. The 2 algebraic models fitted by a nonlinear regression procedure to the data resulted in suitable prediction curves for the constituents (R2 = 0.76 to 0.94). The courses of major milk constituents in llamas during lactation are similar to those in domesticated ruminants, although different in their values. The established curves facilitate the composition of milk replacers at different stages of lactation for nursing llamas whose dams died or are agalactic.

Measurements of the bodyweight and other physical characteristics of 11 llamas (Lama glama) from birth to weaning

The bodyweight (bw), thoracic circumference, length and height of 11 llamas were recorded weekly from birth for 27 weeks. Their mean (sd) birth weight was 11.60 (2.35) kg and their weight increased in curvilinear fashion reaching 61.05 (13.75) kg after 27 weeks. Their average daily gains reached the highest value three weeks after birth and then decreased, reaching the lowest value of 262 g per day at 27 weeks. On a metabolic bw(0.83) basis, the growth of the llamas when their dams were at peak lactation was comparable with that of calves, fawns and lambs. All the measurements were significantly affected by the age, but not by the sex of the young or the parity of the dam. The regression models chosen to predict the bodyweight and weight gain of the llamas yielded R(2) ranging from 0.97 to 0.99. Correlations between bodyweight and other single body measurements were between r=0.68 and 0.77. Single or combined body measurements were good predictors of bodyweight, but additional body measurements added little to the already good fit provided by a single measurement (R(2) ranging from 0.93 to 0.98). The thoracic circumference (R(2)=0.98) and length (R(2)=0.96) were good predictors of the bodyweight of the llamas between birth and 27 weeks old.

Measurement of Milk Intake in Suckling Llamas (Lama glama) Using Deuterium Oxide Dilution

The objective of the study was to estimate daily milk intake in llama crias and relate nutrient intakes at peak lactation to growth data. Milk intake in 11 suckling llamas was estimated from water kinetics using deuterium oxide (D2O) at d 17, 66, and 128 postpartum. Daily milk intakes averaged 2.6, 2.3, and 2.0 kg at 17, 66, and 128 d postpartum, respectively. Milk intake decreased with age when expressed as daily amount, percentage of body weight (BW), or per kilogram of metabolic size, but the influence of age was eliminated when expressed per gram of daily gain. Because llamas only have one young per parturition, milk intake was equivalent to the daily milk output of the dam, which ranged from 27.6 to 96.9 g/kg of maternal BW(0.75). Compared with different ruminant species, milk production in llamas appears to lie between wild and domestic ruminants used for meat production. Nutrients (dry matter, fat, protein, and lactose) and energy intakes from the milk calculated by combining milk intake and milk composition data decreased with age when expressed as daily amount or per 100 g of BW, but when expressed per gram of daily gain, no clear trend was observed. Maintenance requirement for suckling llamas at peak lactation (17 d postpartum) was 312 kJ of ME/kg of BW(0.83). Combined with milk composition data, the present milk intake estimations at different stages of the lactation can be used to establish recommendations for nutrient and energy requirements of suckling llamas.

Diffusion behavior of gap junction hemichannels in living cells

Due to its non-invasive character, fluorescence correlation spectroscopy (FCS) is particularly suited for the investigation of diffusion behavior of proteins in living cells. In this study we have investigated the diffusion properties of CFP-labeled gap junction hemichannels in the plasma membrane of living HeLa cells. Gap junction hemichannels or connexons are the precursors for the cell-cell- or gap junction channels that form large plaques at the contact areas between two adjacent cells. It has been proposed that new channels are recruited into a gap junction structure from a pool of hemichannels that can freely diffuse over the entire plasma membrane. The statistical approach shows that the geometry of the membrane within the focus is the most important property for the form of the autocorrelation curve and in turn for the determination of the diffusion coefficient. On the other hand binding-unbinding events which lead to anomalous diffusion have only a minor effect to the position and shape of the correlation curve compared to the geometry of the membrane.

Interdisziplin�re onkologische Nachsorge am Beispiel von unabh�ngigen Zweittumoren nach Harnblasenkarzinom

The primary intention of oncological follow-up for patients with bladder cancer is the early diagnosis of recurrent local tumors or metastatic disease. The question of subsequent independent tumors has not been assessed as very important. Data from the central cancer registry of Regensburg/Germany for the period 1990-1997 were examined to determine the risk of second primary cancers following an initial bladder cancer. Records of 921 males (mean age: 65.4 years) and 339 females (mean age: 68.0 years) with the primary diagnosis of bladder cancer were analyzed. The minimal follow-up has been 5 years. Bladder cancer patients experience an excess risk of subsequent independent malignancies. The ratio of observed cases to expected cases of subsequent tumors was increased. During the follow-up period, subsequent tumors have been found in 153 (16.6%) male patients and 35 (10.3%) female patients. The most common subsequent malignancies in males were prostate cancer (71 cases) and bronchial cancer (19 cases). Breast cancer (nine cases) and colon cancer were predominant in females. This confirms the good sense of regular oncological follow-up. In this context attention should be directed at tumors of non urological origin, and an interdisciplinary approach with an individual oncological follow-up seems to be useful. The focus should be on the prostate and lung for males and the breast and colon for females.

On the potential of measurement error to induce differential bias on odds ratio estimates: an example from radon epidemiology

It is well established that odds ratios estimated by logistic regression are subject to bias if exposure is measured with error. The dependence of this bias on exposure parameter values, particularly for multiplicative measurement error, and its implications in epidemiology are not, however, as fully acknowledged. We have been motivated by a German West case-control study on lung cancer and residential radon, where restriction to a subgroup exhibiting larger mean and variance of exposure than the entire group has shown higher odds ratio estimates as compared to the full analysis. By means of correction formulae and simulations, we show that bias from additive classical type error depends on the exposure variance, not on the exposure mean, and that bias from multiplicative classical type error depends on the geometric standard deviation (in other words on the coefficient of variation of exposure), but not on the geometric mean of exposure. Bias from additive or multiplicative Berkson type error is independent of exposure distribution parameters. This indicates that there is a potential of differential bias between groups where these parameters vary. Such groups are commonly compared in epidemiology: for example when the results of subgroup analyses are contrasted or meta-analyses are performed. For the German West radon study, we show that the difference of measurement error bias between the subgroup and the entire group exhibits the same direction but not the same dimension as the observed results. Regarding meta-analysis of five European radon studies, we find that a study such as this German study will necessarily result in smaller odds ratio estimates than other studies due to the smaller exposure variance and coefficient of variation of exposure. Therefore, disregard of measurement error can not only lead to biased estimates, but also to inconsistent results and wrongly concluded effect differences between groups.

High-spectral-resolution stimulated Rayleigh-Brillouin scattering at 1 microm

We have demonstrated stimulated Rayleigh-Brillouin scattering at a wavelength of 1.064 microm , using an injection-seeded Nd:YAG laser as a pump laser and a tunable diode laser as a probe laser. Spectra with a good signal-to-noise ratio are obtained despite the low probe-beam power and small gain coefficient in the infrared. Stimulated Rayleigh scattering is readily observable in organic and many other liquids because of absorption by the OH and CH overtone or combination bands. The absorption also causes an asymmetry in the stimulated Brillouin peak. A Rayleigh linewidth of 8 MHz is measured with this approach.

T cells engrafted with a recombinant anti-CD30 receptor target autologous CD30(+) cutaneous lymphoma cells

T cells can be directed to antigen-specific, MHC-independent target cell lysis by grafting with a recombinant receptor with antibody-like specificity. Here, we asked whether T cells from the peripheral blood of a patient with cutaneous T cell lymphoma can be recruited for an immune response against autologous tumor cells. Lymphoma cells with a CD3(-) CD4(+) CD30(+) phenotype and clonal TCR-Vbeta7 rearrangement were isolated from a cutaneous lesion. The lymphoma lesion additionally harbored CD3(+) CD25(+) activated normal T cells despite ongoing tumor progression. Peripheral blood-derived T cells from the lymphoma patient were retrovirally engrafted with a recombinant anti-CD30-scFv-gamma receptor. Upon cocultivation with autologous CD30(+)lymphoma cells, grafted T cells increase IFN-gamma secretion and lyse specifically lymphoma cells with high efficiency, even at an effector to target cell ratio of as low as 1:20. Our data demonstrate that the recombinant anti-CD30-gamma receptor overcomes T cell tolerance for tumor cells and directs T cells specifically against autologous lymphoma cells.

Lung cancer and cigarette smoking in Europe: an update of risk estimates and an assessment of inter-country heterogeneity

Ten case-control studies have been carried out in 6 European countries to investigate the major risk factors for lung cancer. Carcinogenic effect from cigarette smoke was the most relevant interest in our study, which has included 7,609 cases of lung cancer and 10,431 controls, mainly population based. The results indicate elevated odds ratios (ORs; 23.9 among men and 8.7 among women) with attributable risks exceeding 90% for men and close to 60% for women. A large, and statistically significant, variability of the results across countries was detected after adjusting for the most common confounding variables, and after controlling, at least in part, for the instability of the ORs due to the small number of non-smokers in some of the study subsets. This pattern of lung cancer risk associated with cigarettes smoke, across different European regions, reflects inherent characteristics of the studies as well as differences in smoking habits, particularly calendar periods of starting, and it is likely to have been influenced by effect modifiers like indoor radon exposure, occupation, air pollution and dietary habits.

Case-control study on lung cancer and residential radon in western Germany

In a 1990-1996 case-control study in western Germany, the authors investigated lung cancer risk due to exposure to residential radon. Confirmed lung cancer cases from hospitals and a random sample of community controls were interviewed by trained interviewers regarding different risk factors. For 1 year, alpha track detectors were placed in dwellings to measure radon gas concentrations. The evaluation included 1,449 cases and 2,297 controls recruited from the entire study area and a subsample of 365 cases and 595 controls from radon-prone areas of the basic study region. Rate ratios were estimated by using conditional logistic regression adjusted for smoking and for asbestos exposure. In the entire study area, no rate ratios different from 1.0 were found; in the radon-prone areas, the adjusted rate ratios for exposure in the present dwelling were 1.59 (95% confidence interval (CI): 1.08, 2.27), 1.93 (95% CI: 1.19, 3.13), and 1.93 (95% CI: 0.99, 3.77) for 50-80, 80-140, and >140 Bq/m3, respectively, compared with 0-50 Bq/m3. The excess rate ratio for an increase of 100 Bq/m3 was 0.13 (-0.12 to 0.46). An analysis based on cumulative exposure produced similar results. The results provide additional evidence that residential radon is a risk factor for lung cancer, although a risk was detected in radon-prone areas only, not in the entire study area.

Lung cancer in lifetime nonsmoking men - results of a case-control study in Germany

Epidemiological studies of lung cancer among nonsmoking men are few. This case-control study was conducted among lifetime nonsmoking men between 1990 and 1996 in Germany to examine lung cancer risk in relation to occupation, environmental tobacco smoke, residential radon, family history of cancer and previous lung disease. A total of 58 male cases with confirmed primary lung cancer and 803 male population controls who had never smoked more than 400 cigarettes in their lifetime were personally interviewed by a standardized questionnaire. In addition, 1-year radon measurements in the living and bedroom of the subjects' last dwelling were carried out. Unconditional logistic regression was used to calculate odds ratios (OR) and 95% confidence intervals (CI). Having ever worked in a job with known lung carcinogens was associated with a two-fold significantly increased lung cancer risk (OR = 2.2; CI = 1.0-5.0), adjusted for age and region. The linear trend test for lung-cancer risk associated with radon exposure was close to statistical significance, demonstrating an excess relative risk for an increase in exposure of 100 Bq m(-3)of 0.43 (P = 0.052). Nonsignificantly elevated effects of exposure to environmental tobacco smoke in public transportation and in social settings were observed. No associations with a family history of cancer or previous lung diseases were found. Our results indicate that occupational carcinogens and indoor radon may play a role in some lung cancers in nonsmoking men.

Histopathologic findings of lung carcinoma in German uranium miners

BACKGROUND

This study evaluates the histopathology of lung carcinoma in relation to underground radon exposure.

METHODS

Two hundred forty uranium miners of the former Wismut Company in Eastern Germany with histologically or cytologically confirmed primary lung carcinoma were recruited from 3 study clinics between 1991 and 1995. Information on smoking history was obtained by personal interviews, whereas job histories were derived from original payrolls provided by the Wismut Company. Quantitative estimates of occupational radon exposure were based on a job-exposure matrix.

RESULTS

Squamous cell carcinoma (SqCC) was the predominant cell type (43%), followed by adenocarcinoma (AC; 26%), small cell lung carcinoma (SCLC; 23%), and other cell types (8%). Nearly all patients were smokers. Time since first occupational exposure was 42 years on average, the mean cumulative radon exposure 506 working level months. Adenocarcinoma appeared to be more likely than both SCLC and SqCC among miners with low cumulative radiation exposure, long time since first exposure, an older age at diagnosis, and among ex- and never-smokers. In current smokers, lung carcinomas developed at a much lower level of radiation exposure than in ex- and never-smokers. The increase in the relative frequency of SCLC and SqCC at the expense of AC with increasing cumulative radiation exposure was more pronounced among ex- and never-smokers and seemed to be masked among current smokers.

CONCLUSION

The authors' data suggest that all cell types were associated with radon exposure, but high radiation exposure tended to increase the proportion of SCLC and SqCC.

Use of a dielectric stack as a one-dimensional photonic crystal for wavelength demultiplexing by beam shifting

We demonstrate the use of a 30-period dielectric stack structure as a highly dispersive device to spatially separate two beams with a 4-nm wavelength difference by more than their beam width. Unlike previous devices, our structure is simple to fabricate and relatively compact. We discuss possible applications of our device within wavelength-division multiplexing systems.

The OsO4F-, OsO4F2(2)-, and OsO3F3- anions, their study by vibrational and NMR spectroscopy and density functional theory calculations, and the X-ray crystal structures of [N(CH3)4][OsO4F] and [N(CH3)4][OsO3F3]

The fluoride ion acceptor properties of OsO4 and OsO3F2 were investigated. The salts [N(CH3)4][OsO4F] and [N(CH3)4]2[OsO4F2] were prepared by the reactions of OsO4 with stoichiometric amounts of [N(CH3)4][F] in CH3CN solvent. The salts [N(CH3)4][OsO3F3] and [NO][OsO3F3] were prepared by the reactions of OsO3F2 with a stoichiometric amount of [N(CH3)4][F] in CH3CN solvent and with excess NOF, respectively. The OsO4F- anion was fully structurally characterized in the solid state by vibrational spectroscopy and by a single-crystal X-ray diffraction study of [N(CH3)4][OsO4F]: Abm2, a = 7.017(1) A, b = 11.401(2) A, c = 10.925(2) A, V = 874.1(3) A3, Z = 4, and R = 0.0282 at -50 degrees C. The cis-OsO4F2(2-) anion was characterized in the solid state by vibrational spectroscopy, and previous claims regarding the cis-OsO4F2(2-) anion are shown to be erroneous. The fac-OsO3F3- anion was fully structurally characterized in CH3CN solution by 19F NMR spectroscopy and in the solid state by vibrational spectroscopy of its N(CH3)4+ and NO+ salts and by a single-crystal X-ray diffraction study of [N(CH3)4][OsO3F3]: C2/c, a = 16.347(4) A, b = 13.475(3) A, c = 11.436(3) A, beta = 134.128(4) degrees, V = 1808.1(7) A3, Z = 8, and R = 0.0614 at -117 degrees C. The geometrical parameters and vibrational frequencies of OsO4F-, cis-OsO4F2(2-), monomeric OsO3F2, and fac-OsO3F3- and the fluoride affinities of OsO4 and monomeric OsO3F2 were calculated using density functional theory methods.

Synthesis and cytotoxic activity of a glucuronylated prodrug of nornitrogen mustard

A new glucuronylated prodrug of nornitrogen mustard, incorporating the same spacer group as the doxorubicin prodrug HMR 1826, has been prepared. Upon exposure to E. coli beta-glucuronidase, fast hydrolysis occurs but a lower cytotoxicity against LoVo cancer cells is observed compared to the nornitrogen mustard alone. This is explained by cyclization of the intermediate carbamic acid to the inactive chloroethyl oxazolidinone.

Expression and function of beta-glucuronidase in pancreatic cancer: potential role in drug targeting

Improvement of non-surgical strategies is a pivotal task in the treatment of pancreatic cancer. Response to treatment with most anticancer agents has been very poor, probably due to insufficient drug concentration in tumor tissue. Increased response rates during chemotherapy might be achieved by dose escalation; however, this approach is often hampered by severe side effects. One strategy to overcome these adverse effects is application of nontoxic glucuronide prodrugs from which the active moiety is released by beta-glucuronidase within or near the tumor. The use of glucuronide prodrugs in pancreatic cancer requires increased expression of the enzyme in the diseased tissue, a problem that has not been addressed so far. We therefore investigated function and expression of beta-glucuronidase in tissue samples from human healthy pancreas (n=7) and pancreatic adenocarcinoma (n=8), respectively. Comparing the ability of tissue homogenates to cleave the standard substrate 4-methylumbelliferyl-beta-D-glucuronide, we found a significantly increased specific beta-glucuronidase activity (P<0.05) in pancreatic cancer (median: 133; 75% percentile: 286; 25% percentile: 111 nmol/mg per h) as compared to healthy pancreas (median: 74; 75% percentile: 113; 25% percentile: 71 nmol/mg per h). Enzyme kinetic experiments with the model prodrug N-[4-beta-glucuronyl-3-nitrobenzyloxycarbonyl] doxorubicin (HMR 1826) demonstrated bioactivation of HMR 1826 by pancreatic beta-glucuronidase. Enzymatic activity was found to be closely related to enzyme contents (r=0.87) as assessed by Western blot analysis. Our data indicate that increased beta-glucuronidase activity in pancreatic cancer seems to be due to an elevated steady-state level of the protein. This may be the basis for new therapeutic strategies in treatment of pancreatic carcinoma by using glucuronide prodrugs of anticancer agents.

gamma-Ray wavelength standard for atomic scales

The wavelength of the 57Fe Mössbauer radiation is measured with a relative uncertainty of 0.19 ppm by using almost exact Bragg backscattering from a reference silicon crystal. Its value is determined as lambda(M) = 0.860 254 74(16)x10(-10) m. The corresponding Mössbauer photon energy is E(M) = 14 412.497(3) eV. The wavelength of the 57Fe Mössbauer radiation is easily reproducible with an accuracy of at least 10(-11)lambda(M) and could be used as a length standard of atomic dimensions.

Tetrachloro- and tetrabromoarsonium(V) cations: raman and 75As, 19F NMR spectroscopic characterization and X-ray crystal structures of [AsCl4][As(OTeF5)6] and [AsBr4][AsF(OTeF5)5]

The salts [AsX4][As(OTeF5)6] and [AsBr4][AsF(OTeF5)5] (X = Cl, Br) have been prepared by oxidation of AsX3 with XOTeF5 in the presence of the OTeF5 acceptors As(OTeF5)5 and AsF(OTeF5)4. The mixed salts [AsCl4][Sb(OTeF5)6-nCl(n-2)] and [AsCl4][Sb(OTeF5)6-nCl(n)] (n > or = 2) have also been prepared. The AsBr4+ cation has been fully structurally characterized for the first time in SO2ClF solution by 75As NMR spectroscopy and in the solid state by a single-crystal X-ray diffraction study of [AsBr4][AsF(OTeFs)5]: P1, a = 9.778(4) A, b = 17.731(7) A, c = 18.870(8) A, alpha = 103.53(4)degrees, beta = 103.53(4) degrees, gamma = 105.10(4) degrees, V = 2915(2) A3, Z = 4, and R1 = 0.0368 at -183 degrees C. The crystal structure determination and solution 75As NMR study of the related [AsCl4][As(OTeF5)6] salt have also been carried out: [AsCl4][As(OTeF5)6], R3, a = 9.8741(14) A, c = 55.301(11) A, V= 4669(1) A3, Z = 6, and R1 = 0.0438 at -123 degrees C; and R3, a = 19.688(3) A, c = 55.264(11) A, V= 18552(5) A3, Z = 24, and R1 = 0.1341 at -183 degrees C. The crystal structure of the As(OTeF5)6- salt reveals weaker interactions between the anion and cation than in the previously known AsF6- salt. The AsF(OTeF5)5- anion is reported for the first time and is also weakly coordinating with respect to the AsBr4+ cation. Both cations are undistorted tetrahedra with bond lengths of 2.041(5)-2.056(3) A for AsCl4+ and 2.225(2)-2.236(2) A for AsBr4+. The Raman spectra are consistent with undistorted AsX4+ tetrahedra and have been assigned under Td point symmetry. The 35Cl/37Cl isotope shifts have been observed and assigned for AsCl4+, and the geometrical parameters and vibrational frequencies of all known and presently unknown PnX4+ (Pn = P, As, Sb, Bi; X = F, Cl, Br, I) cations have been calculated using density functional theory methods.