Lifetime measurements of metastable states in Fe+

The lifetime of two metastable levels in Fe+ has been measured by laser probing of a stored ion beam. In the dense spectrum of Fe+, the metastable levels a (6)S(5/2) and b (4)D(7/2) were selected and their lifetimes were determined to be 230 +/- 30 and 530 +/- 30 ms, respectively. The lifetimes are compared with previous theoretical results. Metastable lifetime measurements of Fe+ are of great importance for interpretation of spectra from astronomical objects. The present experiment opens for the possibilities to investigate lifetimes of metastable states in complex atomic ions, which have, so far, been unexplored.

Histologic grading in breast cancer--reproducibility between seven pathologic departments. South Sweden Breast Cancer Group

Histologic grade, including tubular formations, nuclear grade, and mitotic activity, is a well-documented prognostic factor in breast cancer. In comparison with other prognostic parameters, the evaluation of histologic grade is cheap and can be performed, in principle, in all cases of breast cancer. One possible disadvantage is that the evaluation may vary between different pathological departments. The aim of the present work was therefore to study the reproducibility of the histologic grading system by distributing haematoxylin-erythrosin-stained slides from 93 invasive breast cancers to the seven pathology departments within the southern healthcare region of Sweden. The evaluation was performed blindly and without any knowledge of other clinical parameters. In 31% of the cases the same histologic grade was obtained for all departments. The overall mean kappa was 0.54, indicating a moderate reproducibility. Of the three factors included in histologic grade, the agreement was best for tubular formations and poorest for nuclear grade and mitotic activity. The overall moderate reproducibility should be considered when the clinical usefulness of histologic grading is compared with other prognostic instruments.

Resonance-enhanced two-photon ionization of ions by Lyman alpha radiation in gaseous nebulae

One of the mysteries of nebulae in the vicinity of bright stars is the appearance of bright emission spectral lines of ions, which imply fairly high excitation temperatures. We suggest that an ion formation mechanism, based on resonance-enhanced two-photon ionization (RETPI) by intense H Lyman alpha radiation (wavelength of 1215 angstroms) trapped inside optically thick nebulae, can produce these spectral lines. The rate of such an ionization process is high enough for rarefied gaseous media where the recombination rate of the ions formed can be 10(-6) to 10(-8) per second for an electron density of 10(3) to 10(5) per cubic centimeter in the nebula. Under such conditions, the photo-ions formed may subsequently undergo further RETPI, catalyzed by intense He i and He ii radiation, which also gets enhanced in optically thick nebulae that contain enough helium.

Immunohistochemical localization of retinoid binding proteins at the materno-fetal interface of the porcine epitheliochorial placenta

Retinol and retinoic acid that are potent modulators of gene expression are vital for development and growth of the conceptus. Apart from being transported across the placenta, retinol and retinoic acid may also be active in the placenta per se. Three proteins involved in 1) serum transport of retinol (retinol binding protein [RBP]), 2) cellular transport and metabolism of retinol (cellular RBP [CRBP] I), and 3) retinoic acid (cellular retinoic acid binding protein [CRABP] I), respectively, have been located by immunohistochemistry during gestation in the porcine placenta. This is a diffuse epitheliochorial placenta composed of areolar-gland subunits, where transport of larger molecules takes place, and interareolar regions, where gas-exchange and trophoblast absorption of hemotroph occur. Immunoreactive-RBP (ir-RBP) as well as CRBP I (ir-CRBP) was detected in uterine glands and in areolar trophoblasts, suggesting that RBP-retinol is secreted by the glands and absorbed by the trophoblasts. Both proteins were present also at the interareolar regions, with ir-CRBP in both the uterine epithelium and the apposing trophoblasts, but ir-RBP only in the former. The localization of ir-CRABP was, in contrast, strictly limited to interareolar trophoblasts. Together these findings suggest that 1) the areolar gland subunits are important for transport of retinol and retinol-RBP, and 2) retinoid binding proteins are involved in the development and growth of the porcine placenta.

[Patent ductus arteriosus. A common clinical problem in extremely premature infants]

An analysis was made of the incidence and treatment regimen of symptomatic patent ductus arteriosus (PDA) in 95 preterm infants treated 1997-1999 in a level three intensive care unit in Stockholm. 47 infants (49 percent) had PDA. Of these 17 infants were managed conservatively (fluid restriction and diuretics), 13 were treated with indomethacin, 10 underwent primary surgical ligation and 7 were treated with indomethacin first and surgery later on. The proportion of infants given "active" therapy (surgery and/or indomethacin) rose from 50 percent in 1997 to 85 percent in 1999. In a stepwise multiple regression analysis low birthweight, septicaemia and need for mechanical ventilation were all independently associated with PDA.

Bone tissue composition, dimensions and strength in female rats given an increased dietary level of vitamin A or exposed to 3,3',4, 4',5-pentachlorobiphenyl (PCB126) alone or in combination with vitamin C

In previous studies we have described structural and functional changes in rat bone tissue caused by 3,3',4,4',5-pentachlorobiphenyl (PCB126). Some of the effects caused by PCB126 resemble those found in vitamin C-deficient rats, as well as those found in rats with a high dietary intake of vitamin A. The present investigation was designed to determine if these PCB126-induced changes could be inhibited by addition of vitamin C to the drinking water and if they could be evoked by vitamin A administration. Five groups of female rats were used in this study, which lasted for 12 weeks. Three of the groups were exposed to PCB126 (total dose 320 microgram/kg, bw), either alone or in combination with vitamin C added to the drinking water (1 and 10 g/l, respectively). One group was given feed with increased level of vitamin A (600000 U/kg pellet) and the fifth group served as controls. Using peripheral quantitative computed tomography (pQCT), it was found that PCB126 increased trabecular density and cortical thickness, but reduced the trabecular area. Furthermore, maximum torque and stiffness of the humerus during torsional testing and serum osteocalcin levels were reduced by PCB126. Of the PCB126 induced effects observed, addition of vitamin C only inhibited the reduction of serum osteocalcin. Like PCB126 vitamin A supplementation increased the inorganic content and the bone density and also reduced the trabecular area and polar moment of inertia but did not increase the cortical thickness or reduce maximum torque, stiffness or serum osteocalcin level. Apparently, the effects induced by PCB126 are not mediated either via decreased vitamin C level or increased vitamin A level.

Timescale of evolution of late radiation injury after postoperative radiotherapy of breast cancer patients

PURPOSE

To evaluate the incidence and prevalence of various signs of late morbidity, their time of appearance and pattern of progression during an observation period up to 34 years in breast cancer patients treated with postoperative radiation therapy after radical mastectomy.

METHODS AND MATERIALS

A group of 71 breast cancer patients received in 1963-1965 aggressive postoperative telecobalt therapy to the parasternal, axillary, and supraclavicular lymph node regions after total mastectomy and axillary clearance. None of the patients received chemotherapy either prior to, or after the irradiation as part of their primary treatment. The prescribed dose to the three lymph node regions was 44 Gy in 11 fractions. Only two of the three fields were treated per day. This total dose was given in 16-17 fractions over 3-4 weeks. Because of the overlap of the supraclavicular and axillary fields, the dose received by the brachial plexus was not the dose that was prescribed. A retrospective dose calculation showed that the total dose to the brachial plexus was 57 Gy, delivered as a complex combination of 1.8 Gy, 3.4 Gy, and 5.2 Gy fractions. This cohort of patients has now been followed to 34 years and the late side effects of the treatment evaluated and scored.

RESULTS

This series is unique in the literature. There is no comparable report of a detailed long-term follow-up in a homogeneously treated group of patients with such a high survival, especially among the younger women, where it is almost 50% at 30 years. This is the reason that they were able to develop some of the very slowly evolving injuries. There was progression of many of the late effects in the period between 5 and 34 years. The more serious morbidities have increased progressively over the whole 34-year follow-up period. Ninety-two percent of the long-term survivors have paralysis of their arm. Other neurological findings included unilateral vocal cord paralysis among 5% of the patients, who developed the disease after a median time of 19 years. All of them were left-sided, indicating a mediastinal involvement of the recurrent nerve. Local recurrence or the appearance of a new primary tumor infiltrating or causing pressure on the recurrent nerve were vigorously investigated and excluded as possible causes of these symptoms.

CONCLUSION

The greatest risk for all cancer patients is the inadequate treatment of their disease, because this is inevitably lethal. The aggressiveness of the therapy and the acceptable risk of complications must therefore be balanced against the risk of recurrence. The neuropathy seems to be closely linked to the development of fibrosis around the nerve trunks. The use of large daily fractions, combined with hot spots from overlapping fields contributed to the severity of the complications.

Cellular invasion by Staphylococcus aureus involves a fibronectin bridge between the bacterial fibronectin-binding MSCRAMMs and host cell beta1 integrins

Although Staphylococcus aureus is primarily considered an extracellular pathogen, recent evidence suggests that this bacterium can invade a variety of nonprofessional phagocytic cells. Here we investigate the early stages of cellular invasion by S. aureus and determine the bacterial and host components that are required for this process. S. aureus expresses two cell surface-associated fibronectin (FN)-binding proteins (FnbpA and FnbpB) that mediate the interaction of the bacteria with both soluble and solid-phase FN in vitro. Using a mutant of S. aureus that lacks the expression of both Fnbps, we show that the expression of either protein is necessary for efficient uptake by the mouse fibroblast line GD25beta1A. Invasion could be inhibited by soluble recombinant proteins encompassing either the FN-binding D repeat region or the A region (and B repeats) of FnbpA, suggesting that the activities of both regions are important in this process. We demonstrate that FN is also required for invasion of this cell line. In the presence of FN-depleted fetal bovine serum, the invasion level was reduced by approximately 40% compared to in the presence of whole fetal bovine serum. Invasion could be further reduced by the addition of anti-mouse FN antibodies to the assay. Finally, we utilize a mutant mouse fibroblast line, which lacks beta1 integrin expression, to demonstrate that host cell beta1 integrins are necessary for efficient cellular invasion. The level of invasion of the mutant cell line GD25 was reduced by approximately 97% compared to the beta1-expressing complemented cell line GD25beta1A. In addition, invasion of the GD25beta1A cell line could be inhibited by an RGD-containing peptide, further implicating a role for integrins in this process. Based on these observations, we put forward a model of S. aureus invasion in which host FN forms a bridge between the bacterial Fnbps and host cell beta1 integrins, leading to bacterial uptake.

Brachial plexopathy after postoperative radiotherapy of breast cancer patients--a long-term follow-up

In 1963-1965 a group of 71 patients operated on for breast cancer with total mastectomy and axillary clearance were given aggressive postoperative telecobalt therapy to the axillary, supraclavicular and parasternal lymph node regions. The prescribed dose to these lymph node regions was 44 Gy in 11 fractions. Only two of the three fields were treated per day. Retrospective dose calculations showed that the total dose in the brachial plexus from the axillary and supraclavicular fields was c. 57 Gy in 16-17 fractions over 3-4 weeks. After a few years, symptoms and signs of brachial plexus injury appeared in many patients, which was reported in some early papers. The cohort has now been followed-up to 34 years. As expected, there was progression of both prevalence and severity of the late effects between 5 and 34 years and 11 of 12 patients who are still alive have paralysis of their arms. The neuropathy seems to be closely linked to fibrosis around the nerve trunks. The use of large daily fractions, in some cases combined with hot spots from overlapping fields, was certainly the cause of the complication.

Ipsilateral local recurrence in relation to therapy and morphological characteristics in patients with ductal carcinoma in situ of the breast

METHOD AND RESULTS

A standardized histopathological protocol has been designed, in which different histological characteristics of ductal carcinoma in situ (DCIS) are reported: nuclear grade (ng), growth pattern according to Andersen et al., necrosis, size of the lesion, resection margins and focality. Using this protocol a re-evaluation of a population-based consecutive series of 306 cases of DCIS has been done as well as a thorough clinical follow-up. After a median follow-up of 63 months, 13% have developed ipsilateral local recurrences, invasive and/or in situ. Ipsilateral local recurrence-free survival (IL-RFS) was significantly better for patients operated with mastectomy (ME) or breast conserving therapy (BCT) with radiotherapy (RT) than for patients operated with BCT without RT (5-year IL-RFS 96% vs 94% vs 79%, P<0.001). In the subgroup of BCT without RT there were significant differences in IL-RFS between histopathological subgroups: ng 1 + 2 (non-high grade) vs ng 3 (high grade; P=0.014), non-high-grade without comedo-type necrosis vs non-high-grade with comedo-type necrosis vs high-grade (the Van Nuys classification system; P=0.025). Growth pattern (not diffuse vs diffuse) and margins (free vs involved or not evaluated) showed a tendency (P=0.07 and 0.05, respectively) to be associated to IL-RFS. In contrast, no significant differences in IL-RFS were found in subgroups based on mode of detection, focality or size. Ninety-four per cent of the local recurrences after BCT appeared at the previous operation site.

CONCLUSIONS

In the BCT without RT group, combinations of either non-high grade and not a diffuse growth pattern or non-high grade and free margins identified groups (constituting approximately 30% of the patients) were at low risk of developing ipsilateral recurrences (6-10%), compared to a 31-37% recurrence risk in the remaining groups during the observed follow-up time. The beneficial effect of post-operative RT for these low-risk groups can be questioned, and should be studied further.

The cytoplasmic tyrosines of integrin subunit beta1 are involved in focal adhesion kinase activation

We have previously shown that mutation of the two tyrosines in the cytoplasmic domain of integrin subunit beta1 (Y783 and Y795) to phenylalanines markedly reduces the capability of beta1A integrins to mediate directed cell migration. In this study, beta1-dependent cell spreading was found to be delayed in GD25 cells expressing beta1A(Y783/795F) compared to that in wild-type GD25-beta1A. Focal adhesion kinase (FAK) tyrosine phosphorylation and activation were severely impaired in response to beta1-dependent adhesion in GD25-beta1A(Y783/795F) cells compared to that in wild-type GD25-beta1A or mutants in which only a single tyrosine was altered (beta1A(Y783F) or beta1A(Y795F)). Phosphorylation site-specific antibodies selective for FAK phosphotyrosine 397 indicated that the defect in FAK phosphorylation via beta1A(Y783/795F) lies at the level of the initial autophosphorylation step. Indeed, beta1A-dependent tyrosine phosphorylation of tensin and paxillin was lost in the beta1A(Y783/795F) cells, consistent with the impairment in FAK activation. In contrast, p130(CAS) overall tyrosine phosphorylation was unaffected by the beta1 mutations. Despite the defect in beta1-mediated FAK activation, FAK was still localized to focal adhesions. Taken together, the phenotype of the GD25-beta1A(Y783/795F) cells resembles, but is distinct from, the phenotype observed in FAK-null cells. These observations argue that tyrosines 783 and 795 within the cytoplasmic tail of integrin subunit beta1A are critical mediators of FAK activation and cell spreading in GD25 cells.

[Fiberoptic endoscopy confirms the cause of upper respiratory obstruction in small children. The most common causes to referrals are sleep apnea syndrome and inspiratory stridor]

Guidelines for the clinical investigation of young children with stridor and sleep apnea are presented. Clinical examination and flexible videolaryngoscopy performed in local anaesthesia are the most important diagnostic tools for this group of children. If the impairment is severe or an objective evaluation is needed the child should also undergo nocturnal polygraphic recording and lung function tests. Out of 43 children examined with flexible videolaryngoscopy 21 had positive findings, laryngomalacia being the most common diagnosis. Flexible videolaryngoscopy is a good complement to laryngoscopy under general anaesthesia. It can be performed as early as in the neonatal period.

Effects of tobacco smoke on tumor growth and radiation response of dunning R3327 prostate adenocarcinoma in rats

BACKGROUND

The influence of tobacco smoke has been investigated on the growth rate and histology of prostate cancer, both in untreated tumors and in those subjected to fractionated irradiation.

METHODS

Twenty-five rats were implanted bilaterally with Dunning R3327 tumor fragments at 10 weeks of age. Approximately 3 months later, they were randomly allocated to two groups, one of which was exposed to tobacco smoke for an hour each day, 5 days a week. Three weeks later the groups were further subdivided into two groups which acted as controls or were subjected to 5 daily doses of 6 Gy. The tumors were measured weekly to construct growth curves. At a fixed time, 9 weeks or 20 weeks later, the animals were sacrificed and the tumors were removed for histological evaluation of the tissue composition. Sections from each tumor were scored in a morphometric analysis of the fraction of the area of tumor that was occupied by (epithelial) tumor cells, by stroma, or by luminal spaces. In addition, the density of mast cells was assessed in adjacent sections stained with toluidine blue.

RESULTS

Smoking caused only minor changes in the growth rates of both the control and the irradiated tumors. At the cellular level, smoking caused a small but significant increase in the fraction of tumor cells relative to controls. Irradiation also caused a small but significant decrease in tumor cell fraction compared to controls, even after 20 weeks of regrowth. This difference was reduced in the smoking and irradiation group. The main difference observed was in the mast cell numbers. Smoking caused a 4-fold increase in mast-cell density. Irradiation caused an even greater increase (25-fold). The combination of smoking and irradiation resulted in an intermediate increase (10-fold).

CONCLUSIONS

Long-term smoke exposure can slightly alter the growth rate and morphology of Dunning R3327 rat prostatic adenocarcinoma, but our study does not show a negative effect on the outcome of radiation treatment of this tumor model. We have also demonstrated a highly elevated number of mast cells in the irradiated group, and have shown that smoke exposure significantly depressed the radiation-induced enhancement of the number of mast cells.

Detection of colorectal tumor and inflammatory bowel disease during follow-up of patients with initial diagnosis of irritable bowel syndrome

BACKGROUND

We wanted to estimate the incidence of irritable bowel syndrome (IBS) and functional dyspepsia (FD) in the general population, and the detection of colorectal tumor (CRT) and inflammatory bowel disease (IBD) after the diagnosis of IBS and FD.

METHODS

Patients aged 20-79 years newly diagnosed with IBS (N = 2956) or FD (N = 9900), together with a comparison cohort randomly sampled from the general source population, were followed-up during a mean time of 3 years.

RESULTS

We found an overall incidence of 10.3 per 1000 person-years for FD and 2.6 per 1000 person-years for IBS. There was a greater prevalence of depression, stress, fatigue, and pain disorders among IBS and FD patients than in the general population. During the 1st year after a diagnosis of IBS the cumulative risk of detecting CRT was close to 1% in IBS patients. After the 1st year the risk of CRT in IBS patients was close to that in the general population. We found a significantly increased risk of detecting IBD among patients initially diagnosed as having IBS (relative risk (RR), 16.3; 95% confidence interval (CI), 6.6-40.7), which was constant during all the follow-up period. No association was found between dyspepsia and CRT, or IBD.

CONCLUSION

IBS and FD shared some comorbidity features, yet demographics and incidence rates were different. Unlike the detection of colorectal tumor, the excess risk of IBD after an initial diagnosis of IBS was cumulatively increased during all the follow-up period. The continuously increased risk of IBD detection in IBS patients favors a true association between IBS and IBD.

Calcaneal ultrasound measurements are determined by age and physical activity. Studies in two Swedish random population samples

AIM

To present reference values and correlations with body composition, blood variables and lifestyle factors.

SUBJECTS

Two random population samples from Göteborg, Sweden, one comprising 184 men and 455 women aged 25-64 years (MONICA) and the other 860 women aged 55-82 years (BEDA) were studied.

METHODS

Calcaneal ultrasound measurement (LUNAR Achilles) and bioimpedance were measured. Smoking habits, coffee consumption, physical activity, psychological stress, education and marital status, as well as blood lipids, blood pressure, and fractures were studied.

RESULTS

Broadband ultrasound attenuation and stiffness were higher in men than in women (P < 0. 001), but speed of sound did not differ between sexes. Speed of sound, broadband ultrasound attenuation and stiffness decreased with age (P < 0.001). In both sexes speed of sound, broadband ultrasound attenuation and stiffness correlated positively to body size variables, and negatively with smoking in women after adjustment for age. Speed of sound, broadband ultrasound attenuation and stiffness were positively related to physical activity in both sexes, and these relationships were the only ones that remained in multivariate analyses in addition to age (negative). Osteoporotic fractures increased with age. Speed of sound, broadband ultrasound attenuation and stiffness were lower amongst women with osteoporotic fractures.

CONCLUSION

Speed of sound, broadband ultrasound attenuation and stiffness decreased with age and increased with physical activity, but body weight and height were not correlated in multivariate analyses. Osteoporotic fractures increased with age and were associated with lower calcaneal ultrasound values.

Overall mortality among patients surviving an episode of peptic ulcer bleeding

STUDY OBJECTIVE

The authors investigated whether patients who have survived an acute episode of peptic ulcer bleeding (PUB) have an excess long term all cause mortality compared with the general population free of PUB.

DESIGN

Follow up study of previously identified cohort of patients with a PUB episode and a general population cohort.

SETTING

The source population included all people aged 30 to 89 years, registered with general practitioners in the United Kingdom.

PATIENTS

All patients alive one month after the PUB episode constituted the cohort of PUB patients (n = 978). A control group of 5000 people was randomly sampled from the source population. The same eligibility criteria as for patients with PUB were applied to the control series. Also, controls had to be free of PUB before start date.

MAIN RESULTS

Relative risk of mortality among PUB patients was 2.1, 95% CI: 1.7, 2.6) compared with the general population. This increased mortality risk occurred mainly in the patients less than 60 years old. No difference was observed between men and women. The excess mortality was not only circumscribed to deaths attributable to recurrent gastrointestinal bleed, but also cardiovascular, cancer and other causes.

CONCLUSIONS

People who have survived an acute episode of PUB have a reduced long term survival compared with the general population. This reduction was stronger among middle age patients than in the elderly.

Expression of integrin subunit beta1B in integrin beta1-deficient GD25 cells does not interfere with alphaVbeta3 functions

We have expressed the beta1B integrin subunit in beta1-deficient GD25 cells to examine beta1B functions without the interference of endogenous beta1A expression. As previously reported [Retta et al., 1998, Mol. Biol. Cell 9, 715-731], the beta1B integrins did not mediate cell adhesion under normal culture conditions, while the presence of 0.3 mM Mn(2+) allowed beta1B integrins to support adhesion. Mn(2+), as well as the small soluble peptide GRGDS, induced a beta1B conformation, which was recognized by the mAb 9EG7, a marker for active or ligand-bound integrins. beta1B integrins were found to localize to a subset of focal contacts in a ligand-independent manner on fibronectin, but not on vitronectin. However, clustering of beta1B did not induce tyrosine phosphorylation of FAK, p130(Cas), or paxillin, as studied by beta1B-mediated adhesion, to fibronectin in the presence of Mn(2+) or to anti-beta1 antibody in DMEM. Induction of ligand-occupied conformation by the GRGDS peptide during the adhesion to anti-beta1 antibody also failed to trigger FAK phosphorylation. Stimulation of tyrosine phosphorylation on FAK, p130(Cas), and paxillin by adhesion via integrin alphaVbeta3 to fibronectin or vitronectin was not disturbed in GD25-beta1B cells compared to the untransfected GD25 cells, nor were any negative effects of beta1B observed on alphaVbeta3-mediated cell attachment, spreading, and actin organization, or on the cell proliferation rate. These results show that the reported negative effects of beta1B on adhesive events do not apply to alphaVbeta3-dependent interactions and suggest that they may specifically act on beta1 integrins.

Determination of the border between the transmembrane and cytoplasmic domains of human integrin subunits

In this study we have determined the position of the C-terminal end of the transmembrane domains of human integrin subunits (alpha2, alpha5, beta1, beta2) in microsomal membranes using the glycosylation mapping technique. In contrast to the common view, the transmembrane helices were found to extend roughly to Phe(1129) in alpha2, to Phe(1026) in alpha5, to Ile(757) in beta1, and to His(728) in beta2. The alpha-carbon of the conserved lysine present near the C-terminal end of the transmembrane helix (Lys(1125) in alpha2, Lys(1022) in alpha5, Lys(752) in beta1, and Lys(724) in beta2) is buried in the plasma membrane, and the charged amino group most likely reaches into the polar head-group region of the lipid bilayer. A possible role for the conserved lysine in integrin function is discussed.