Effectiveness of Oral Iron Therapy in Anemic Inpatient Pregnant Women: A Single Center Retrospective Cohort Study

Background and aim Oral iron therapy is effective in treating iron deficiency anemia in outpatient pregnant women but has not been studied in inpatient pregnant women. We aimed to evaluate the effect of oral iron therapy versus no therapy during hospitalization on maternal and neonatal outcomes in women with anemia who are hospitalized for pregnancy-related morbidities (i.e., preterm premature rupture of membranes, preterm labor, pre-eclampsia, abnormal placentation, or fetal monitoring). Methods A retrospective, single-center study was conducted in hospitalized pregnant women (2018 to 2020) with inpatient stays of more than three days. The primary outcome was a change in hemoglobin level from admission to delivery in women treated with oral iron compared with those left untreated. Secondary outcomes included the total amount of iron administered before delivery, the time interval from admission to delivery, and neonatal effects. Results Two hundred sixty-three women were admitted, 79 women had anemia, and 29 (36.7%) received at least one dose of oral iron. Baseline patient characteristics were similar between groups. The median (interquartile range) dose of iron in the oral iron group was 1185.0 (477.0, 1874.0) mg. Neither absolute hemoglobin before delivery (control group: 10.0±1.2 g/dL; iron group: 10.1±1.1 g/dL; p=0.774) nor change in hemoglobin from admission to delivery (control group: -0.1±1.1 g/dL vs. iron group: 0.4±1.1 g/dL; p=0.232) differed between groups. Women in the control group had shorter length of stay (LOS) median (IQR) than women in the iron group (control group: 7.1 (5.0, 13.7) days; iron group: 11.4 (7.4, 25.9) days; p=0.03). There were no differences in maternal mode of delivery, though each group had high rates of cesarean delivery (control group: 53.7%; iron group: 72.4%; p=0.181). There were no differences in estimated blood loss at delivery (control group: 559±401; iron group: 662.1±337.4;p=0.264) in either group. Neonatal birthweight (control group: 1.9±0.7 kg; iron group: 1.9±0.7 kg; p=0.901), birth hemoglobin (control group: 16.3±2.2 g/dL; iron group: 16±2.2 g/dL; p=0.569), neonatal intensive care unit (NICU) admission (control group: 93.3%; iron group: 84.8%;p=0.272 ), or neonatal death (control group: 8.9%; iron group: 3%; p=0.394) were not different between groups. Conclusions Oral iron administered to anemic inpatient pregnant women was not associated with higher hemoglobin concentrations before delivery. Lack of standardized iron regimens and short hospital stays may contribute to the inefficacy of oral iron for this inpatient pregnant population. The small sample size and retrospective nature of this study are limiting factors in drawing conclusive evidence from this study.

Pan-cancer analysis of genomic scar patterns caused by homologous repair deficiency (HRD)

Homologous repair deficiency (HRD) is present in many cancer types at variable prevalence and can indicate response to platinum-based chemotherapy and PARP inhibition. We developed a tumor classification system based on the loss of function of genes in the homologous recombination repair (HRR) pathway. To this end, somatic and germline alterations in BRCA1/2 and 140 other HRR genes were included and assessed for the impact on gene function. Additionally, information on the allelic hit type and on BRCA1 promoter hypermethylation was included. The HRDsum score including LOH, LST, and TAI was calculated for 8847 tumors of the TCGA cohort starting from genotyping data and for the subcohort of ovarian cancer also starting from WES data. Pan-cancer, deleterious BRCA1/2 alterations were detected in 4% of the tumors, while 18% of the tumors were HRD-positive (HRDsum ≥ 42). Across 33 cancer types, both BRCA1/2 alterations and HRD-positivity were most prevalent in ovarian cancer (20% and 69%). Pan-cancer, tumors with biallelic deleterious alterations in BRCA1/2 were separated strongly from tumors without relevant alterations (AUC = 0.89), while separation for tumors with monoallelic deleterious BRCA1/2 alterations was weak (AUC = 0.53). Tumors with biallelic deleterious alterations in other HHR genes were separated moderately from tumors without relevant alterations (AUC = 0.63), while separation for tumors with such monoallelic alterations was weaker (AUC = 0.57). In ovarian cancer, HRDsum scores calculated from WES data correlated strongly with HRDsum scores calculated from genotyping data (R = 0.87) and were slightly (4%) higher. We comprehensively analyzed HRD scores and their association with mutations in HRR genes in common cancer types. Our study identifies important parameters influencing HRD measurement and argues for an integration of HRDsum score with specific mutational profiles.

Intranasal fentanyl and inhaled nitrous oxide for fracture reduction: The FAN observational study

INTRODUCTION

Procedural sedation and analgesia (PSA) are frequently used for fracture reduction in pediatric emergency departments (ED). Combining intranasal (IN) fentanyl with inhalation of nitrous oxide (N₂O) allow for short recovery time and obviates painful and time-consuming IV access insertions.

METHODS

We performed a bicentric, prospective, observational cohort study. Patients aged 4-18years were included if they received combined PSA with IN fentanyl and N₂O for the reduction of mildly/moderately displaced fracture or of dislocation. Facial Pain Scale Revised (FPS-R) and Face, Leg, Activity, Cry, Consolability (FLACC) scores were used to evaluate pain and anxiety before, during and after procedure. University of Michigan Sedation Score (UMSS), adverse events, detailed side effects and satisfaction of patients, parents and medical staff were recorded at discharge. A follow up telephone call was made after 24-72h.

RESULTS

90 patients were included. There was no difference in FPS-R during the procedure (median score 2 versus 2), but the FLACC score was significantly higher as compared to before (median score 4 versus 0, Δ 2, 95% CI 0, 2). Median UMSS was 1 (95% CI 1, 2). We recorded no serious adverse events. Rate of vomiting was 12% (11/84). Satisfaction was high among participants responding to this question 85/88 (97%) of parents, 74/83 (89%) of patients and 82/85 (96%) of physicians would want the same sedation again.

CONCLUSION

PSA with IN fentanyl and N₂O is effective and safe for the reduction of mildly/moderately displaced fracture or dislocation, and has a high satisfaction rate.

The Fan Study: Intranasal Fentanyl and Inhaled Nitrous Oxide for Fracture Reduction

BACKGROUND: Recently, intranasal (IN) fentanyl and inhaled nitrous oxide/oxygen (N2O) mixture have been increasingly used for procedural sedation and analgesia (PSA) alone or in combination. There is a lack of data on the efficacy of these combined agents.

OBJECTIVES: To evaluate the efficacy of IN fentanyl and N2O as PSA for the reduction of mildly-to-moderately displaced fractures and dislocations.

DESIGN/METHODS: We performed a prospective, observational cohort study between September 2014 and October 2015. Patients were recruited at CHU Sainte Justine (Montréal, Canada) and Royal Children Hospital (Melbourne, Australia). Patients between the age of 4 and 18 years were eligible if PSA consisted of IN fentanyl and N2O for the reduction of mildly-to-moderately displaced fractures or dislocations. Patients received at least IN fentanyl 1.5 mcg/kg (100 mcg max) and at least a 50/50% mixture of N2O with oxygen. Primary outcome was the efficacy of PSA measured by the patient assigned Facial Pain Scale-Revised (FPS-R). The Face, Legs, Activity, Cry, Consolability (FLACC) scale was also recorded. Depth of sedation was evalu-ated using the University of Michigan Sedation Scale (UMSS). Adverse events were recorded following the criteria of the Consensus Panel on Sedation Research of PERC/PECARN. Additional data concerning satisfaction or discomfort were evaluated via questionnaires, and follow-up telephone calls were made to elicit information on adverse events after discharge.

RESULTS: A total of 91 patients aged 9.7±3.0 years were enrolled. There was no difference between the median FPS-R score during the procedure compared to before: Median 2 and 2 (median difference 0 [95% CI 0, 0]), respectively. The FLACC score was higher during the procedure than before: Median 4 and 0 (median difference 2 [95% CI 1, 3]). UMSS was 1 (95% CI 1, 2) during the procedure. 42 (46%) patients had adverse events, all mild: vertigo (20%), nausea (16%)]or vomiting (12%). A total of 85/88 (97%) parents and 82/85 (96%) ED physicians would want the same sedation in another procedure.

CONCLUSION: PSA with IN fentanyl and N2O seems effective in our cohort study, as evaluated by patient assigned FPS-R. Patients were minimally sedated. Adverse events were frequent but mild. Overall, parents and medical staff would want the same agents used in another procedure. Thus, PSA with IN fentanyl and N2O appears to be an attractive option for reduction of mildly displaced fractures or dislocations.

Age-related differences in processing visual device and task characteristics when using technical devices

With aging visual feedback becomes increasingly relevant in action control. Consequently, visual device and task characteristics should more and more affect tool use. Focussing on late working age, the present study aims to investigate age-related differences in processing task irrelevant (display size) and task relevant visual information (task difficulty). Young and middle-aged participants (20-35 and 36-64 years of age, respectively) sat in front of a touch screen with differently sized active touch areas (4″ to 12″) and performed pointing tasks with differing task difficulties (1.8-5 bits). Both display size and age affected pointing performance, but the two variables did not interact and aiming duration moderated both effects. Furthermore, task difficulty affected the pointing durations of middle-aged adults moreso than those of young adults. Again, aiming duration accounted for the variance in the data. The onset of an age-related decline in aiming duration can be clearly located in middle adulthood. Thus, the fine psychomotor ability "aiming" is a moderator and predictor for age-related differences in pointing tasks. The results support a user-specific design for small technical devices with touch interfaces.

Association of PHB 1630 C>T and MTHFR 677 C>T polymorphisms with breast and ovarian cancer risk in BRCA1/2 mutation carriers: results from a multicenter study

BACKGROUND

The variable penetrance of breast cancer in BRCA1/2 mutation carriers suggests that other genetic or environmental factors modify breast cancer risk. Two genes of special interest are prohibitin (PHB) and methylene-tetrahydrofolate reductase (MTHFR), both of which are important either directly or indirectly in maintaining genomic integrity.

METHODS

To evaluate the potential role of genetic variants within PHB and MTHFR in breast and ovarian cancer risk, 4102 BRCA1 and 2093 BRCA2 mutation carriers, and 6211 BRCA1 and 2902 BRCA2 carriers from the Consortium of Investigators of Modifiers of BRCA1 and BRCA2 (CIMBA) were genotyped for the PHB 1630 C>T (rs6917) polymorphism and the MTHFR 677 C>T (rs1801133) polymorphism, respectively.

RESULTS

There was no evidence of association between the PHB 1630 C>T and MTHFR 677 C>T polymorphisms with either disease for BRCA1 or BRCA2 mutation carriers when breast and ovarian cancer associations were evaluated separately. Analysis that evaluated associations for breast and ovarian cancer simultaneously showed some evidence that BRCA1 mutation carriers who had the rare homozygote genotype (TT) of the PHB 1630 C>T polymorphism were at increased risk of both breast and ovarian cancer (HR 1.50, 95%CI 1.10-2.04 and HR 2.16, 95%CI 1.24-3.76, respectively). However, there was no evidence of association under a multiplicative model for the effect of each minor allele.

CONCLUSION

The PHB 1630TT genotype may modify breast and ovarian cancer risks in BRCA1 mutation carriers. This association need to be evaluated in larger series of BRCA1 mutation carriers.

[Clinical and paraclinical course of melanocytoma of the optic disk. Contribution of spectral- and time-domain OCT in the study of 10 patients]

INTRODUCTION

Melanocytoma of the optic disk is a rare, benign, slow-growing tumor. We analyzed the clinical and paraclinical features of melanocytomas followed at the Fort-de-France University Hospital to expose and compare characteristics from new clinical imaging.

PATIENTS AND METHOD

This was a prospective study of 10 patients with a melanocytoma of the optic disk. The principal features studied were the ophthalmoscopic findings, the visual field defects, fluorescein angiography features, and the comparison between standard time-domain optical coherence tomography (OCT) characteristics and the latest spectral-domain OCT findings.

RESULTS

The mean age of the patients at diagnosis was 49.2 years. All the patients were from the French West Indies. The lesion was discovered incidentally in 90% of the cases. Visual acuity was normal in 70% of the cases. Visual field defects were present at the first visit in 80% of the cases. Tumor growth was monitored in 50% of the cases during a mean follow up of 4.8 years. The in-depth extension into chorioretina and laterally into the retina were better visualized in spectral-domain OCT than in time-domain OCT as hyperreflective granular dots.

CONCLUSION

Optic disk melanocytoma appears to be a singular benign tumor that is seen more frequently in dark-skinned patients. Most melanocytomas do not cause significant visual impairment but can show substantial growth in size for many years of follow-up. A malignant transformation is always to fear in case of atypical development. Spectral domain OCT seems to be an important tool in the assessment of extension and follow-up.

Practice and carryover effects when using small interaction devices

The use of interaction devices in modern work often challenges the human motor system, especially when these devices introduce unfamiliar transformations to the user. In this paper we evaluated expert performance and skill differences between experts and novices when using small motion- and force-controlled interaction devices (touchpad and mini-joystick) in an applied text-editing task. Firstly, experts performed better with their familiar input device than with an unfamiliar one. Particularly touchpad experts operating the unfamiliar mini-joystick showed highly asymmetric carryover costs. Results showed that the efficient performance of experts depended on domain-specific skills, which were not transferable. Secondly, with considerable practice (more than observed for simple and short tasks) novices were brought up to higher levels of performance. The motion-transformation between hand and cursor action was easier in understanding and application than the force-transformation. Thus, the touchpad was used more efficiently than the mini-joystick. In conclusion, practice effects found so far are considerably underestimated when it comes to an applied task. The results give reason to develop and implement skill-sensitive training procedures, since the acquisition of domain-specific skills is critical for expert performance. As a consequence, training procedures might be essential for complex applications and/or unfamiliar device transformations.

Cerebellar stem cells act as medulloblastoma-initiating cells in a mouse model and a neural stem cell signature characterizes a subset of human medulloblastomas

Cells with stem cell properties have been isolated from various areas of the postnatal mammalian brain, most recently from the postnatal mouse cerebellum. We show here that inactivation of the tumor suppressor genes Rb and p53 in these endogenous neural stem cells induced deregulated proliferation and resistance to apoptosis in vitro. Moreover, injection of these cells into mice formed medulloblastomas. Medulloblastomas are the most common malignant brain tumors of childhood, and despite recent advances in treatment they are associated with high morbidity and mortality. They are highly heterogeneous tumors characterized by a diverse genetic make-up and expression profile as well as variable prognosis. Here, we describe a novel ontogenetic pathway of medulloblastoma that significantly contributes to understanding their heterogeneity. Experimental medulloblastomas originating from neural stem cells preferentially expressed stem cell markers Nestin, Sox2 and Sox9, which were not expressed in medulloblastomas originating from granule-cell-restricted progenitors. Furthermore, the expression of these markers identified a subset of human medulloblastomas associated with a poorer clinical outcome.

The TP53 Arg72Pro and MDM2 309G>T polymorphisms are not associated with breast cancer risk in BRCA1 and BRCA2 mutation carriers

Background:

The TP53 pathway, in which TP53 and its negative regulator MDM2 are the central elements, has an important role in carcinogenesis, particularly in BRCA1- and BRCA2-mediated carcinogenesis. A single nucleotide polymorphism (SNP) in the promoter region of MDM2 (309T>G, rs2279744) and a coding SNP of TP53 (Arg72Pro, rs1042522) have been shown to be of functional significance.

Methods:

To investigate whether these SNPs modify breast cancer risk for BRCA1 and BRCA2 mutation carriers, we pooled genotype data on the TP53 Arg72Pro SNP in 7011 mutation carriers and on the MDM2 309T>G SNP in 2222 mutation carriers from the Consortium of Investigators of Modifiers of BRCA1/2 (CIMBA). Data were analysed using a Cox proportional hazards model within a retrospective likelihood framework.

Results:

No association was found between these SNPs and breast cancer risk for BRCA1 (TP53: per-allele hazard ratio (HR)=1.01, 95% confidence interval (CI): 0.93–1.10, P_trend=0.77; MDM2: HR=0.96, 95%CI: 0.84–1.09, P_trend=0.54) or for BRCA2 mutation carriers (TP53: HR=0.99, 95%CI: 0.87–1.12, P_trend=0.83; MDM2: HR=0.98, 95%CI: 0.80–1.21, P_trend=0.88). We also evaluated the potential combined effects of both SNPs on breast cancer risk, however, none of their combined genotypes showed any evidence of association.

Conclusion:

There was no evidence that TP53 Arg72Pro or MDM2 309T>G, either singly or in combination, influence breast cancer risk in BRCA1 or BRCA2 mutation carriers.

Sensumotor transformation of input devices and the impact on practice and task difficulty

In the present study, the usability of two laptop input devices, touchpad and trackpoint, is evaluated. The focus is set on the impact of sensumotor transformation of input devices on practice and task difficulty. Thirty novices and 14 experts operated either touchpad or trackpoint over a period of 1600 trials of a point-click task. As hypothesized, novices and experts operated the touchpad by 15% faster compared to the trackpoint. For novices, performance rose distinctly and levelled off after 960 trials. This consolidation occurred earlier than reported in literature (1400-1600 trials) and, contrary to the assumption, learning was similar for touchpad and trackpoint. The impact of task difficulty dropped remarkably by practice, which points at a more general than specific task learning. In conclusion, ergonomic guidelines can be derived for the user-specific optimization of the usage of touchpad and trackpoint. Actual and potential applications of this research include the user-specific optimization of laptop input devices. Within the theoretical framework of psychomotor models, a profound knowledge of user behaviour in human-computer interaction is provided. Ergonomic guidelines can be derived for the efficient usage of laptop input devices and an optimized hardware and software design.

Notebook input devices put to the age test: the usability of trackpoint and touchpad for middle-aged adults

In two experiments, the usability of input devices integrated into computer notebooks was under study. The most common input devices, touchpad (experiment 1) and trackpoint (experiment 2) were examined. So far, the evaluation of mobile input devices has been restricted to younger users. However, due to ongoing demographic change, the main target group of mobile devices will be older users. Therefore, the present study focused on ageing effects. A total of 14 middle-aged (40-65 years) and 20 younger (20-32 years) users were compared regarding speed and accuracy of cursor control in a point-click and a point-drag-drop task. Moreover, the effects of training were addressed by examining the performance increase over time. In total, 640 trials per task and input device were executed. The results show that ageing is a central factor to be considered in input device design. Middle-aged users were significantly slower than younger users when executing the different tasks. Over time, a significant training effect was observed for both devices and both age groups, although the benefit of training was greater for the middle-aged group. Generally, the touchpad performance was higher than the trackpoint performance in both age groups, but the age-related performance decrements were less distinct when using the touchpad.

A ‘Nonsense’ Mutation Leads to Aberrant Splicing of hMLH1 in a German Hereditary Non-polyposis Colorectal Cancer Family

Hereditary Non-polyposis Colorectal Cancer (HNPCC) is an autosomal dominant cancer predisposition syndrome caused by germline mutations in at least four genes encoding integral components of the cellular DNA mismatch repair (MMR) system. The spectrum of genetic alterations encompasses missense- and nonsense mutations, intronic mutations affecting splice donor or acceptor sites as well as small-scale deletions and insertions. We have identified a 'nonsense' mutation that activates a cryptic splice site generating an in frame deletion of the last 17 codons of exon1 of the hMLH1 gene causing HNPCC in a German family. We present a comprehensive genetic analysis of this family that demonstrates important aspects of HNPCC pathogenesis.

The reliability of immunohistochemistry as a prescreening method for the diagnosis of hereditary nonpolyposis colorectal cancer (HNPCC)--results of an international collaborative study

Hereditary nonpolyposis colorectal cancer syndrome (HNPCC) is an autosomal dominant condition accounting for 2-5% of all colorectal carcinomas as well as a small subset of endometrial, upper urinary tract and other gastrointestinal cancers. An assay to detect the underlying defect in HNPCC, inactivation of a DNA mismatch repair enzyme, would be useful in identifying HNPCC probands. Monoclonal antibodies against hMLH1 and hMSH2, two DNA mismatch repair proteins which account for most HNPCC cancers, are commercially available. This study sought to investigate the potential utility of these antibodies in determining the expression status of these proteins in paraffin-embedded formalin-fixed tissue and to identify key technical protocol components associated with successful staining. A set of 20 colorectal carcinoma cases of known hMLH1 and hMSH2 mutation and expression status underwent immunoperoxidase staining at multiple institutions, each of which used their own technical protocol. Staining for hMSH2 was successful in most laboratories while staining for hMLH1 proved problematic in multiple labs. However, a significant minority of laboratories demonstrated excellent results including high discriminatory power with both monoclonal antibodies. These laboratories appropriately identified hMLH1 or hMSH2 inactivation with high sensitivity and specificity. The key protocol point associated with successful staining was an antigen retrieval step involving heat treatment and either EDTA or citrate buffer. This study demonstrates the potential utility of immunohistochemistry in detecting HNPCC probands and identifies key technical components for successful staining.

Comprehensive genetic counseling for families at risk for HNPCC: impact on distress and perceptions

The aim of the study was to explore distress and health beliefs before and after comprehensive interdisciplinary counseling in families at risk for hereditary non-polyposis colorectal cancer (HNPCC). Results reported here were derived from a consecutive sample of 65 counselees [31 patients with colorectal cancer (CRC) and 34 unaffected at-risk persons] who participated in interdisciplinary counseling provided by human geneticists, surgeons, and psycho-oncologists before genetic testing. Data were collected from self-administered questionnaires before, as well as 4-6 weeks after, counseling. Distress and perceptions specific to HNPCC were assessed at both timepoints using standardized as well as author-derived instruments. Distress declined after counseling, as did worries related to HNPCC. An increase was found in personal belief in control of cancer risk, for instance, in the perceived efficacy of early detection of CRC. We also observed a trend toward greater anticipated ability to cope with a positive gene test after counseling. Changes after counseling were generally more pronounced for persons at risk, as compared to patients with cancer. The decrease in distress was partly attributable to an increase in personal self-confidence. One-third of the sample reported enhanced communication specific to hereditary disease within the family after counseling. A substantial minority, however, said they experienced increased worry and physical symptoms after counseling. Overall, counselees demonstrated less stress and perceived cancer threat as well as enhanced beliefs regarding personal control over cancer, suggesting an overall beneficial impact of comprehensive counseling. Further research is needed to identify those individuals most at risk for increased fear and worry related to HNPCC so that they may be most appropriately counseled.

[Glioblastoma multiforme as a manifestation of Turcot syndrome]

Turcot's syndrome, clinically characterized by the coincident occurrence of primary tumors of the colon and the central nervous system, can genetically be divided into two syndromes: familial adenomatous polyposis (FAP) and hereditary nonpolyposis colon carcinoma (HNPCC). In the present case, a 60-year-old patient with glioblastoma multiforme and a history of hereditary malignomas is described as an example of a HNPCC-associated Turcot's syndrome. New molecular biological methods and results give deeper insight into clinical syndromes, and the better understanding improves diagnostics, therapy, and outcome estimations, even in rare diseases. In the present case, a new germinal mutation could be identified.

Evaluation of Bethesda guidelines in relation to microsatellite instability

PURPOSE

The Bethesda guidelines were developed for selection of patients whose tumors should be tested for high microsatellite instability. This study examined the validity of the different Bethesda criteria in relation to microsatellite instability status to simplify their use in clinical practice.

METHODS

A total of 164 patients with colorectal or hereditary nonpolyposis colorectal cancer-associated cancers were registered on the basis of the Amsterdam criteria without age limitations (11 cases), multiple tumors (2 cases), the accumulation of colorectal cancer in the family (no first-degree relatives affected or the index patient's age up to 50 years; 45 cases), an early age at onset up to 50 years (13 cases), morphologic and histopathologic manifestations (right-sided colorectal cancer, mucinous undifferentiated histology; 1 case), and the Bethesda criteria (92 cases). The microsatellite instability status of tumors was determined using the International Collaborative Group on Hereditary Non-Polyposis Colorectal Cancer marker reference panel.

RESULTS

When applying all Bethesda criteria, high microsatellite instability tumors were identified in our hereditary nonpolyposis colorectal cancer registry with a sensitivity of 87 percent. Twenty-nine percent (27/92) of the Bethesda-positive patients displayed high microsatellite instability compared with 6 percent of patients (4/72) not meeting these criteria (P < 0.001). Only Bethesda Criteria 1, 3, and 4 showed a significantly different distribution of the microsatellite instability status when compared with those of the remaining patients registered (P < or = 0.001). These three criteria detected high microsatellite instability tumors in 48 percent (10/21), 50 percent (18/36), and 31 percent (21/67) of patients, respectively. When applying these criteria only, a cumulative detection rate of 77 percent of all (24/31) high microsatellite instability cases was found, thereby identifying 89 percent of high microsatellite instability tumors among the Bethesda-positive patients. Patients matching Criteria 1, 3, and 4 frequently showed hMSH2 or hMLH1 germline mutations and tumor-specific loss of protein expression.

CONCLUSION

In our hereditary nonpolyposis colorectal cancer registry the complete Bethesda criteria showed the highest sensitivity to identify patients with high microsatellite instability tumors. However, for general medical practice outside academic centers, three criteria are reasonably accurate for adequate high microsatellite instability tumor selection.

Systematic identification of genes with coding microsatellites mutated in DNA mismatch repair-deficient cancer cells

Microsatellite instability (MSI) caused by deficient DNA mismatch-repair functions is a hallmark of cancers associated with the hereditary nonpolyposis colorectal cancer (HNPCC) syndrome but is also found in about 15% of all sporadic tumors. Most affected microsatellites reside in untranslated intergenic or intronic sequences. However, recently few genes with coding microsatellites were also shown to be mutational targets in MSI-positive cancers and might represent important mutation targets in their pathogenesis. The systematic identification of such genes and the analysis of their mutation frequency in MSI-positive cancers might thus reveal major clues to their functional role in MSI-associated carcinogenesis. We therefore initiated a systematic database search in 33,595 distinctly annotated human genes and identified 17,654 potentially coding mononucleotide repeats (cMNRs) and 2,028 coding dinucleotide repeats (cDNRs), which consist of n > or = 6 and n > or = 4 repeat units, respectively. Expression pattern and mutation frequency of 19 of these genes with the longest repeats were compared between DNA mismatch repair-deficient (MSI(+)) and proficient (MSS) cancer cells. Instability frequencies in these coding microsatellite genes ranged from 10% to 100% in MSI-H tumor cells, whereas MSS cancer cells did not show mutations. RT-PCR analysis further showed that most of the affected genes (10/15) were highly expressed in tumor cells. The approach outlined here identified a new set of genes frequently affected by mutations in MSI-positive tumor cells. It will lead to novel and highly specific diagnostic and therapeutic targets for microsatellite unstable cancers.

Magnetic splitting of valence states in ferromagnetic and antiferromagnetic lanthanide metals

The magnetic splitting of Delta(2) valence states in the heavy lanthanide metals Gd, Tb, Dy, and Ho was studied in epitaxial films by angle-resolved photoemission, revealing an essentially Stoner-like temperature dependence in all cases. It scales linearly with the 4f spin moment, even in the case of the helical antiferromagnet Ho. Such a behavior can be explained by a substantial localization of the corresponding wave function in the c direction. The helical magnetic structure was confirmed for the thin Ho films by in situ resonant magnetic x-ray diffraction.

Sampling technique influences the detection of K-ras mutations in normal appearing mucosa of colorectal cancer patients

Based on three colorectal cancer cell lines with specified K-ras status, a sensitive PCR-RFLP assay was established detecting one K-ras mutant among 106 wild-type cells. Using this assay for tissues of 124 colorectal cancer patients, 59 tumor (46%) and 11 mucosa samples (9%) were found to harbor a K-ras mutation. When using the same scalpel for collecting tumor and mucosa tissues (group A), 18% of the patients had a matching K-ras mutation in both tissues, but this coincidence was seen in 3% of patients only, when separate scalpels were used (group B). Thus we conclude that the sampling technique used for collecting specimens is a major contributor to the detection of K-ras mutations in normal appearing mucosa when a highly sensitive detection technique is used.

Molecular screening of potential HNPCC patients using a multiplex microsatellite PCR system

Microsatellite instability (MSI) is a molecular hallmark of the H ereditary N on- P olyposis C olorectal C ancer (HNPCC) syndrome occurring in about 80-90% of the tumours and also in sporadic tumours of different organs, albeit at lower frequency. Highly unstable colorectal tumours (MSI-H) have different histopathological features and tend to have a better prognosis compared to neoplasms without (MSS) or with low levels of microsatellite instability (MSI-L). Since MSI classification allows the identification of potential HNPCC patients and might represent a valuable diagnostic parameter an increasing demand for high-throughput microsatellite analysis will arise. Therefore, we have adapted five diagnostic microsatellites, m(odified) ACTC, mBAT26, mD5S107, mD5S406 and mD13S153, to allow coamplification. Using this multiplex polymerase chain reaction (PCR) system 29 colorectal tumour tissues with known MSI status could be unambiguously identified as MSI-H (13 cases) or MSI-L/MSS (16 cases). Highly unstable colorectal tumour detection frequency of individual markers reached 77% (mD5S406), 85% (mACTC), 85% (mD5S107), 92% (D13S153) and 100% (mBAT26) showing similar sensitivity but improved specificity as compared with a microsatellite reference panel. In a prospective analysis of 31 colorectal tumours, the multiplex PCR system identified five MSI-H cases. Multiplex MSI PCR is a time saving and cost-effective method not restricted to specific technical equipment and applicable to a variety of microsatellite-based genotyping approaches.

[Modification of surgical strategy in HNPCC by molecular and clinical aspects]

Because of the positive correlation between Amsterdam criteria and positive MSI analysis, a subtotal colectomy with ileorectal anastomosis seems to be indicated in patients with positive Amsterdam criteria to eliminate the high risk of metachronous colon cancer. In patients with an identified mutation in one of the known mismatch repair genes, a subtotal colectomy is indicated as well. In patients with positive Bethesda criteria, apart from the Amsterdam criteria, a subtotal colectomy seems only to be indicated if a positive MSI analysis is available.

Differential diagnosis of malignant tumours in the abdominal cavity of rats after intraperitoneal injection of crocidolite or benzo[a]pyrene

In our investigation (i.p. test), crocidolite and benzo[a]pyrene, both caused a progression from initially reactive, then autonomously transformed proliferation of myofibroblasts and undifferentiated mesenchymal cells to malignant, multidirectionally differentiated (desmin and ED-1 positive) fibro-histiocytic tumours. Immunohistochemically these tumours showed no morphological characteristics (for example co-expression of vimentin and keratin in spindle-shaped tumour cells) of human asbestos-associated malignant mesotheliomas. On the other hand many tumour cells induced by crocidolite and benzo[a]pyrene had an ultrastructural appearance resembling fibroblasts and myofibroblasts. These have been demonstrated in only a few desmoplastic and sarcomatous mesotheliomas in human beings. None of the tumours revealed the typical ultrastructural features of epitheloid or transitional mesotheliomas. Apparently, both carcinogenic substances induce the transformation of undifferentiated pluripotent mesenchymal cells in rat peritoneum, regardless of their localization in the submesothelial compartment or perivascular connective tissue (preferentially after crocidolite application) or in the connective tissue pseudocapsule of major benzo[a]pyrene containing beeswax/tricaprylin depots in the mesometrium and mesenterial fatty tissue. In this way asbestos fibres in this animal experiment do not seem to induce an arrest in differentiation of intermediate or immature mesothelial cells as supposed formerly, but rather affect undifferentiated mesenchyme cells and myofibroblasts. This is an explanation for the immunohistochemical expression of markers of muscular differentiation in these tumour cells, which is known to occur in human malignant fibro-histiocytic tumours. If supplementary immunohistochemical investigations with different keratin antibodies also fail to confirm the mesothelial differentiation of the tumours induced in our i.p. test, the decision to call them "mesotheliomas" should be reconsidered. Further immuno-transmission-electron microscopical investigations with intermediate filament or macrophage antibodies are needed to clarify whether the term malignant "fibrohistiocytic sarcoma", "mesenchymoma" or "mesothelioblastoma" would be more correct from the morphological point of view.

Importance of the lateral view in the evaluation of suspected brain death

The authors present two cases of clinical brain death that failed to meet the criteria for whole brain death using Tc-99m HMPAO. Conventional anterior cerebral flow studies demonstrated no intracerebral perfusion. Anterior static images also failed to show cerebral activity. However, the lateral images clearly demonstrate cerebellar activity. These cases demonstrate the importance of Tc-99m HMPAO as the agent of choice in evaluating brain death and the necessity of lateral views to meet the criteria for whole brain death. Cerebellar perfusion challenges the present criteria for whole brain death. New criteria must re-evaluate the present technology.

Analysis of v-Ha-ras and v-fos oncogene transduction into a mouse epidermal cell line with "initiated" phenotype in culture but normal skin phenotype in vivo

Cell line SCR722 was derived from adult SENCAR mouse epidermal cells initiated in culture by treatment with the carcinogen N-methyl-N'-nitro-N-nitrosoguanidine and selection for foci proliferating in medium with calcium levels that induce terminal differentiation in normal cells. Expansion of one of these foci and two additional cell clonings produced cell line SCR722, which was near-tetraploid and formed normal skin when grafted to athymic nude mouse hosts. However, unlike normal keratinocytes, SCR722 cells fail to suppress papilloma formation when grafted along with papilloma cell line SP-1. For optimum growth in culture, SCR722 cells required fibroblast-conditioned medium and 0.5 mM Ca2+. SCR722 cells had a wild-type c-Ha-ras gene but had lost their requirement for conditioned medium in culture and produced dysplastic papillomas in grafts when transduced with the v-Ha-ras gene. SCR722 cells stably expressing the v-fos gene produced normal epidermis in grafts, but when these cells were transduced with the v-Ha-ras gene, they produced carcinomas. Clones with greater expression of the transfected v-fos gene had a more invasive phenotype in vivo. These results indicate that carcinogen treatment of epithelial cells can result in an altered but nontumorigenic phenotype that may be at risk for becoming a more advanced neoplastic state with additional genetic alterations.

SENCAR mouse skin tumors produced by promotion alone have A to G mutations in codon 61 of the c-rasHa gene

SENCAR mice, developed by selective breeding for high susceptibility to skin carcinogenesis by initiation with 7,12-dimethylbenz[a]anthracene and promotion with 12-O-tetradecanoylphorbol-13-acetate (TPA), form squamous papillomas in approximately 20% of animals treated repeatedly with TPA, without chemical initiation. DNA from eight skin tumors produced by a TPA-only protocol and four cell lines derived from these tumors was amplified by polymerase chain reaction and analyzed by discriminative oligonucleotide hybridization using oligomers specific for various c-rasHa gene codon 61 sequences. Five tumors and three cell lines had CAA (wild-type) to CGA mutations. In addition, one tumor had a CAA to CTA mutation, for a total of six of eight tumors having an activating mutation at this codon. Two tumors and one cell line had no codon 61 mutations detectable by this method. Since tumors derived from promotion-only protocols presumably originated from constitutively initiated cells, we examined tumor-free skins of untreated newborn and eight-month-old retired breeders and of 78-88-week-old SENCAR mice of both sexes, which were treated with TPA for 10 weeks starting at age 16-28 weeks and were untreated thereafter. Only the wild-type c-rasHa gene codon 61 sequence was seen, suggesting that the constitutively initiated cell population, if present, is below the limit of detection by this method.

7,12-Dimethylbenz[a]anthracene-induced mouse keratinocyte malignant transformation independent of Harvey ras activation

Independent clones of mouse keratinocytes initiated in vitro gave rise to tumor phenotypes typical of mouse skin multistage carcinogenesis and histologically similar to human tumors of the skin, and head and neck. High-molecular-weight genomic DNAs isolated from two 7,12-dimethylbenz[a]anthracene (DMBA)-initiated murine epithelial carcinoma cell lines and one papilloma cell line were examined for transforming activity by transfection into NIH3T3 cells. DNAs from each of these cell lines resulted in the formation of foci morphologically unlike foci containing an activated c-Ha-ras oncogene. Following polymerase chain reaction amplification of the c-Ha-ras gene, Xba I restriction analysis and oligonucleotide differential hybridization did not detect 61st, 12th, or 13th codon mutations. Southern and Northern analysis confirmed that the normal c-Ha-ras gene was not activated by amplification or overexpression. These results provide evidence that 7,12-dimethylbenz[a]anthracene-induced malignant transformation of murine keratinocytes occurred independent of point mutations associated with c-Ha-ras activation. The absence of an activated c-Ha-ras oncogene in these cell lines distinguishes our model from other mouse models of carcinogenesis and may provide a model for functional genetic changes during initiation and progression of human epithelial cancers.

ras gene activation and aberrant expression of keratin K13 in ultraviolet B radiation-induced epidermal neoplasias of mouse skin

Both papillomas and squamous cell carcinomas (SCC) induced in mouse epidermis by initiation with 7,12-dimethylbenz[a]anthracene (DMBA) and promotion with 12-O-tetradecanoylphorbol-13-acetate (TPA) exhibit aberrant expression of a type I keratin, K13, that is normally characteristic of terminal differentiation of internal stratified epithelia. There is evidence that the aberrant expression of K13 depends on the presence of an activated ras gene in mouse epidermal keratinocytes (Sutter et al., Mol Carcinog 4:467-476, 1991). To assess the general validity of this hypothesis, we investigated both aberrant K13 expression and activation of each of the three members of the ras gene family in epidermal tumors induced in four different mouse strains (SKH-1 hr, SENCAR, BALB/c, and C3H/He) by chronic irradiation with ultraviolet (UV) B. The tumor collection comprised nine papillomas and 30 well or poorly differentiated SCC. Aberrant K13 expression occurred in only five of 39 tumors and was restricted to SCC of both types. This indicates that aberrant K13 expression in UV-induced epidermal tumors was intrinsically different from that in chemically induced tumors. Polymerase chain reaction analysis of the tumors for different point mutations in codons 12, 13, and 61 of the Ha-ras and Ki-ras genes and in codon 61 of the N-ras gene revealed that only one of the well differentiated tumors from a SKH-1 hr mouse exhibited a GGA-->GAA mutation in codon 12 of the Ha-ras gene. Although this tumor was also positive for aberrant K13 expression, such a correlation could not be made for the remaining K13-expressing tumors. This indicates that the activation of one of the members of the ras gene family is not a general prerequisite for the aberrant expression of K13 in mouse epidermal keratinocytes.

Carcinogen-specific mutational pattern in the p53 gene in ultraviolet B radiation-induced squamous cell carcinomas of mouse skin

We have examined 35 epidermal tumors induced in mice of four different strains by chronic exposure to ultraviolet B radiation for the presence of aberrations in the p53 tumor suppressor gene. Polymerase chain reaction products from p53 exons 5 to 8 were screened by single-strand conformation polymorphism analysis and sequencing. Base substitutions were found in seven tumors (20%). All mutations occurred at dipyrimidine sequences; most frequent were C-->T single base and CC-->TT tandem transitions suggesting the involvement of UV radiation in the genesis of the mutations. Three base substitutions were located at codon 148, and all dipyrimidine-derived mutations occurred at sites where the sequence is present in the nontranscribed DNA strand, indicating some site and strand specificity of the ultraviolet B-induced p53 mutations.

Aberrant in vitro expression of keratin K13 induced by Ca2+ and vitamin A acid in mouse epidermal cell lines

Normally the expression of the murine type I keratin K13 is restricted to differentiating cells of internal squamous epithelia which line the oral cavity and the upper digestive tract. Recently, however, we were able to show that K13 is aberrantly but constitutively expressed without its normal type II partner K4 also in differentiating parts of 7,12-dimethylbenz(a)anthracene (DMBA/TPA) 12-O-tetradecanoylphorbol-13-acetate-induced squamous cell carcinomas of mouse back skin, whereas its likewise suprabasal expression in papillomas is variable (Nischt et al., Mol. Carcinogenesis 1, 96-108, 1988). In an attempt to reproduce the aberrant expression of K13 in a mouse in vitro system, we have investigated eight established murine epidermal cell lines for their putative ability to express K13. The cell lines differed distinctly in their derivation and comprised cell lines originating from DMBA/TPA induced papillomas (line SP1) or DMBA-treated adult mouse epidermis (line 308) as well as cell lines derived from DMBA or DMBA/TPA-treated primary epidermal keratinocytes (lines PDV and MCA 3D) and cell lines which arose spontaneously by long-term culture of normal epidermal keratinocytes (lines HEL 30 degrees HEL 37 degrees, HELP I and HELP III). We show that, independent of their derivation, all cell lines possess the intrinsic property to aberrantly express K13. Invariably the K13 gene is not expressed when the lines are cultured under low Ca2+ conditions (0.05 mM) and thus prevented from differentiation. Its expression can, however, be induced either by increasing the extracellular Ca2+ concentration or by the addition of physiological concentrations of vitamin A acid to low Ca2+ medium. Whereas in the latter case, K13 expression occurs without concomitant induction of morphological differentiation of the cells, Ca2+ elevation in the culture medium induces squamous differentiation and K13 expression occurs only in differentiating cells, thus reflecting the situation observed in in vivo tumors. All cell lines exhibit a concentration optimum for the stimulatory agents; however, the degree of maximal K13 expression varies considerably among the individual cell lines and shows a striking correlation with the reported tumorigenicity of the lines after transplantation to animals. In contrast, a tentatively suggested correlation between the activation of the Ha-ras gene and the aberrant expression of K13 (Nischt et al., Mol. Carcinogenesis 1, 96-108, 1988) could not definitely be confirmed since we observed K13 expression also in three cell lines which did not carry a mutation in codon 61 of the Ha-ras gene.(ABSTRACT TRUNCATED AT 400 WORDS)