Velamentous cord insertion in dichorionic and monochorionic twin pregnancies - Does it make a difference?

OBJECTIVE: To estimate the prevalence of velamentous cord insertion (VCI) in dichorionic (DC) and monochorionic (MC) twins with and without twin-twin transfusion syndrome (TTTS), and to study the associated outcomes. METHODS: We recorded the type of umbilical cord insertion in all consecutive DC and MC placentas examined in two European tertiary medical centers. The association between VCI and perinatal outcomes was estimated and compared. RESULTS: A total of 1498 twin placentas were included in this study (DC placentas n = 550, MC placentas without TTTS n = 513 and MC placentas with TTTS n = 435). The prevalence of VCI in DC, MC without TTTS and MC with TTTS groups was 7.6%, 34.7% and 36.1%, respectively (P < 0.001). In MC twins (non-TTTS and TTTS groups), VCI was associated with severe birth weight discordance (odds ratio [OR] 4.76 95% CI 2.43, 10.47 and OR 4.52 95% CI 1.30, 28.59, respectively). In MC twins without TTTS, VCI was associated with small for gestational age (OR 1.66, 95% CI 1.12, 2.50). VCI was significantly associated with increased risk of intrauterine fetal demise in MC twins, and this effect was greater in the non-TTTS group (OR 2.71 95% CI 1.38, 5.47). These associations did not occur in DC group. Gestational age at birth was lower in the presence of VCI in the DC and MC twins without TTTS. CONCLUSION: Our findings confirm that the prevalence of VCI is higher in MC twins than in DC twin pregnancies. VCI is an important indicator of adverse perinatal outcome, particularly in MC twins.

Cherenkov-type diamond detectors for measurements of fast electrons in the TORE-SUPRA tokamak.

The paper presents a schematic design and tests of a system applicable for measurements of fast electron pulses emitted from high-temperature plasma generated inside magnetic confinement fusion machines, and particularly in the TORE-SUPRA facility. The diagnostic system based on the registration of the Cherenkov radiation induced by fast electrons within selected solid radiators is considered, and electron low-energy thresholds for different radiators are given. There are some estimates of high thermal loads, which might be deposited by intense electron beams upon parts of the diagnostic equipment within the TORE-SUPRA device. There are some proposed measures to overcome this difficulty by the selection of appropriate absorption filters and Cherenkov radiators, and particularly by the application of a fast-moving reciprocating probe. The paper describes the measuring system, its tests, as well as some results of the preliminary measurements of fast electrons within TORE-SUPRA facility.

neu/erbB-2 amplification identifies a poor-prognosis group of women with node-negative breast cancer. Toronto Breast Cancer Study Group.

PURPOSE: It remains a challenge to predict which women with axillary node-negative (ANN) breast cancer at greatest risk of relapse may benefit most from adjuvant therapy. Increases in neu/erbB-2 have been implicated in breast cancer prognosis. Although overexpression has been investigated extensively, this study represents the first prospective assessment of the prognostic value of neu/erbB-2 DNA amplification in a cohort of women with newly diagnosed ANN. METHODS: A consecutive series of women was monitored for recurrence (median follow-up duration, 36 months) and tumors from 580 individuals were analyzed for amplification. The association of amplification with risk of recurrence was examined in survival analyses with traditional and histologic markers as prognostic factors. RESULTS: Neu/erbB-2 was amplified in 20% of cases. We found an increased risk of disease recurrence when neu/erbB-2 was amplified > or = twofold that persisted with adjustment for other prognostic factors (relative risk, 2.36; P = .002). We found some evidence that amplification was more important in patients who received chemotherapy compared with untreated patients. CONCLUSION: neu/erbB-2 amplification is an independent prognostic factor for risk of recurrence in ANN breast cancer. Women with tumors without neu/erbB-2 amplification have a good prognosis; aggressive therapy in this group is therefore difficult to justify. On the other hand, even with adjuvant chemotherapeutic treatment, women whose tumors exhibit neu/erbB-2 amplification have an increased risk of recurrence. We encourage a randomized trial to compare more aggressive adjuvant chemotherapy versus standard chemotherapy for ANN women whose tumors exhibit neu/erbB-2 amplification.

Randomized clinical trial of breast irradiation following lumpectomy and axillary dissection for node-negative breast cancer: an update. Ontario Clinical Oncology Group.

BACKGROUND: Breast-conservation surgery is now commonly used to treat breast cancer. Postoperative breast irradiation reduces cancer recurrence in the breast. There is still controversy concerning the necessity of irradiation of the breast in all patients. PURPOSE: We present an update of results from a randomized clinical trial designed to examine the efficacy of breast irradiation following conservation surgery in the treatment of women with axillary lymph node-negative breast cancer. The patients were enrolled from April 1984 through February 1989. Initial results were published in 1992 after a median follow-up time of 43 months. It was reported that recurrence of cancer in the breast occurred in 5.5% of the patients who received breast irradiation compared with 25.7% of those who did not. No difference in survival was detected between the two treatment groups. Now that the median patient follow-up has reached 7.6 years, the trial end points have been re-examined and an attempt has again been made to identify a group of patients at low risk for recurrence of cancer in the breast. METHODS: Eight hundred thirty-seven patients with node-negative breast cancer were randomly assigned to receive either radiation therapy (n = 416) or no radiation therapy (n = 421) following lumpectomy and axillary lymph node dissection. The cumulative local recurrence rate as a first event, distant recurrence (i.e., occurrence of metastasis) rate, and overall mortality rate for the treatment groups were described by the Kaplan-Meier method and compared with the use of the logrank test. The Cox proportional hazards model was used to adjust the observed treatment effect for the influence of various prognostic factors (patient age, tumor size, estrogen receptor level, and tumor histology) at study entry on the outcomes of local breast recurrence, distant recurrence, and overall mortality. All P values resulted from the use of two-tailed statistical tests. RESULTS: One hundred forty eight (35%) of the nonirradiated patients and 47 (11%) of the irradiated patients developed recurrent cancer in the breast (relative risk for patients in the former versus the latter group = 4.0; 95% confidence interval = 2.83-5.65; P < .0001). Ninety-nine (24%) of the patients in the former group have died compared with 87 (21%) in the latter group. Age (< 50 years), tumor size (> 2 cm), and tumor nuclear grade (poor) continued to be important predictors for local breast relapse. On the basis of these factors, we were unable to identify a subgroup of patients with a very low risk for local breast cancer recurrence. Tumor nuclear grade, as previously reported, and tumor size were important predictors for mortality. CONCLUSIONS: Breast irradiation was shown to reduce cancer recurrence in the breast, but there was no statistically significant reduction in mortality. A subgroup of patients with a very low risk for local breast recurrence who might not require radiation therapy was not identified.

Cytospins--an alternative method for fine-needle aspiration cytology of the breast: a study of 148 cases.

The aim of this study was to evaluate the cytospin technique as an alternative method to prepare fine-needle aspiration (FNA) specimens of the breast. To do so, the cytology of 148 breast FNAs that had been prepared by the cytospin technique and that had histologic correlation, was reviewed. All the cases that were diagnosed as malignant by cytology were proved malignant after surgical excision, and there were no false-positive results. All but two cases diagnosed as benign by cytology proved to be benign on excision. The two false-negative cases were missed due to sampling error. The cytological features seen on cytospins were similar to those seen on conventional direct smears. The major advantage of this method is that no aspirate is unsatisfactory due to unskilled direct smear technique. This, along with its good correlation with histology, proves that the cytospin method is an effective alternative to conventional direct smears for breast FNA.

Hemorrhagic shock in rats.

Rats are commonly used as models of hemorrhagic shock. Both constant-pressure and constant-volume protocols have been used, although the latter is considered by some to be a better model of human shock. However, differences in survival have been reported when the same experiment is done by different investigators. Changes in oxygen consumption have been reported to correlate with mortality after shock, and these changes may be implicated in the variability seen in different experimental studies. Using the constant-volume model, in which a given percentage of the animal's estimated blood volume is withdrawn, we have determined oxygen consumption rates before and after hemorrhage in Sprague Dawley rats. Our results indicate that specific oxygen consumption rates decrease once rats reach a certain weight, but removing a given percentage of blood reduces the rate by a constant amount regardless of the weight of the animal. In addition, there appears to be a "critical" level of oxygen consumption needed for survival. Thus use of a constant-volume protocol could result in survival for smaller but not larger rats. It is suggested that rat weights must be the same to compare results from different investigators.

Gynecologic cytology from the perspective of the Laboratory Proficiency Testing Program, Ontario, Canada.

The accumulated test results from annual proficiency testing of approximately 150 cytology laboratories during the period 1977-1992 were analyzed. Several features of the test program are presented, including the adaptability of the uniform diagnostic terminology that was in use throughout. Observations include the impact of screening by a technologist; the better diagnostic performance generally, but not exclusively, in larger-volume laboratories; the degree of reproducibility of reporting in the laboratory; the ease of diagnosis in some diagnostic categories; and patterns observed in "false negative" and "false positive" rates. The follow-up analysis of suboptimal performance is recorded, and remedial and educational aspects are emphasized. The impact of levels of performance on the specific population being screened is correlated with the data on laboratory caseloads and with hospital vs. nonhospital laboratories.

Randomized clinical trial to assess the effectiveness of breast irradiation following lumpectomy and axillary dissection for node-negative breast cancer.

BACKGROUND: Although the conservation management of breast cancer has become a routine method of treatment in most centers, there is still considerable controversy surrounding the ultimate minimum treatment required for node-negative breast cancer to achieve adequate local control. PURPOSE: Our purpose was to assess the value of breast irradiation in reducing breast relapse following conservation surgery for node-negative breast cancer. We attempted to define low-risk groups of women for breast and distant site relapse (i.e., recurrence outside the breast) who might be spared breast irradiation or adjuvant systemic therapy. METHODS: Eight hundred thirty-seven patients were randomly assigned to receive radiation therapy or no radiation therapy following lumpectomy and axillary dissection for node-negative breast cancer. RESULTS: Breast irradiation reduced relapse in the breast from 25.7% in the controls to 5.5% in the irradiated patients. There was no difference in survival between the two groups (median follow-up, 43 months). A low-risk group (less than 5% chance of relapse in the breast without irradiation) could not be defined. Tumor size (greater than 2 cm), age (less than 40 years), and poor nuclear grade were important predictors for breast relapse. Age (less than 50 years) and poor nuclear grade were important predictors for mortality. The presence of ductal carcinoma in situ did not predict breast relapse. CONCLUSIONS: Breast irradiation significantly reduces breast relapse, but it does not influence survival. Important predictors of breast relapse are age, tumor size, and nuclear grade, but not the presence of ductal carcinoma in situ. Age and, in particular, nuclear grade predict survival. IMPLICATIONS: Further follow-up may define an acceptable low-risk group for breast relapse. Until then, we recommend that all patients receive breast irradiation. Systemic adjuvant therapy should be considered for patients with poor nuclear grade tumors.

Formaldehyde exposure and health status in households.

This report describes a case study concerned with acute and subacute health effects of formaldehyde in the indoor air, which is based on a large group of control houses and houses retroinsulated 4 to 5 years earlier with urea formaldehyde foam insulation (UFFI). Both groups underwent an environmental and health assessment on two occasions separated by an interval of 12 months, during which about one-half of the UFFI group performed remedial work on their houses. The results show that in the first survey of the study population, before remedial work, there was a moderate excess of many adverse health status indicators among the UFFI subset relative to the controls. This was associated with the presence of direct exposure-response relationships between formaldehyde levels in the UFFI houses and the prevalence of a number of symptoms. No comparable relationships were seen among the controls. At the second survey, performed following the removal of the UFFI, there was an appreciable reduction in the excess of most adverse health status indicators among the UFFI subjects. This improvement in health status among the UFFI removal subset was not associated with any significant diminution of formaldehyde exposures, although the previously observed exposure-response relationships had vanished. These observations imply that the findings obtained in the preremedial stage of the study cannot be explained by formaldehyde exposure alone.

Regional blood-brain glucose transfer and glucose utilization in chronically hyperglycemic, diabetic rats following acute glycemic normalization.

Regional rates of brain glucose utilization (rCMRglc) and glucose influx (rJin), along with regional brain tissue glucose concentrations, were measured in chronically hyperglycemic diabetic (CHD) rats following acute glycemic normalization. These results were compared to those obtained in nondiabetic normoglycemic controls. The diabetic rats were evaluated at 6-8 weeks following i.p. streptozotocin injection. All rats were N2O (70%) sedated, paralyzed, and artificially ventilated for study. Acutely normoglycemic (plasma glucose = 8.5 mumol/ml), demonstrated significantly higher (p less than 0.05) rCMRglc and rJin values in 8 of the 11 regions analyzed. Tissue/plasma glucose concentration ratios were significantly greater than control in 9 of 11 regions. Prior to acute glycemic normalization, rCMRglc values in CHD rats were either unchanged or moderately lower than control. These findings indicate that no blood-brain barrier glucose transport repression is present in CHD rats. In fact, the results suggest an increased transport capacity. The increased rCMRglc observed in the acutely normalized CHD rats may be a manifestation of the "hypoglycemic symptoms" observed in chronically hyperglycemic patients following acute glycemic reductions to the normal range. The present results imply that these symptoms are not related to the presence of a relative cerebral glucopenia, as others have suggested.

Comparison of health of occupants and characteristics of houses among control homes and homes insulated with urea formaldehyde foam. I. Methodology.

The methodology of a study in which a comparison is made of the health and house characteristics of the occupants of 231 control homes and 571 houses containing urea formaldehyde foam insulation (UFFI) is described. All homes and occupants were examined on two occasions separated by an interval of 12 months, during which two-thirds of the UFFI houses performed remedial work. The occupants were examined using a health questionnaire and a series of objective tests including pulmonary function, nasal airway resistance, sense of smell, nasal surface cytology, and patch tests. The houses were assessed using a questionnaire and measurements of indoor formaldehyde and carbon dioxide levels. No obvious bias has been identified in this survey with respect to the representativeness of the population studied, the classification of the UFFI and control groups, and the input from both the respondents and observers. The symptom responses made by individuals within the same households were not correlated. Quality control assessment of the objective health tests and formaldehyde sampling and assays demonstrated that these procedures remained stable over the two phases of the study, with the exception of the expected decrease in the pulmonary flow rates over 1 year and a small unexpected increase in the forced vital capacity and the forced expiratory volume in 1 s.

Comparison of health of occupants and characteristics of houses among control homes and homes insulated with urea formaldehyde foam. III. Health and house variables following remedial work.

This report describes the second survey of a group of 762 control and urea formaldehyde foam insulated (UFFI) houses performed following an interval of 1 year, after about two-thirds of the UFFI households either had their UFFI removed or performed other UFFI-related remedial work. The UFFI subjects who lived in remedial houses showed a decline in indicators of impaired health status, to roughly equalize with those whose houses were not altered; they continued to show a small excess of adverse health indicators relative to the controls, but at a somewhat lower level than seen in the first survey. This improvement was not associated with changes in indoor levels of formaldehyde. Weak exposure-response relationships were observed between formaldehyde and upper and lower respiratory symptoms, but mainly in the combined UFFI and control populations; these are interpreted as representing the contribution of background levels of formaldehyde to the prevalence of respiratory complaints in the general population. The principal findings of this study were primarily based on subjective variables, but most could be directly validated by objective measurements in the UFFI and control subjects. The support for a causal relationship between impaired health and living in a UFFI house is considered to be moderately strong. However the demonstrated adverse effects are generally minor in nature.

Comparison of health of occupants and characteristics of houses among control homes and homes insulated with urea formaldehyde foam. II. Initial health and house variables and exposure-response relationships.

A health survey was conducted on 1726 occupants of urea formaldehyde foam insulated (UFFI) houses and 720 residents of control homes. The occupants of the UFFI houses showed a modest excess of many symptoms relative to the controls. This excess of complaints was contributed mainly by the residents of households which were intending to have their UFFI removed and by onsets which followed the installation of UFFI. There were no associated abnormalities in nasal airway resistance, sense of smell, pulmonary function, or patch tests for allergy to formaldehyde. However, the UFFI subjects intending to have their UFFI removed demonstrated a small increase in nasal epithelial squamous metaplasia. The indoor formaldehyde levels of the UFFI houses were about 20% higher than in the controls, while the carbon dioxide levels were similar in both groups. The UFFI subjects showed positive relationships between level of formaldehyde exposure and the presence of a number of symptoms, which were largely dependent on a small group of formaldehyde values that were in excess of 0.12 ppm. A number of the exposure-response relationships were enhanced by UFFI. These results suggested that some adverse health effects of UFFI were explained by formaldehyde alone while others were related to the combined effects of formaldehyde and an additional UFFI-related factor(s) which was not identified.

Lymphomatoid granulomatosis.

The clinical and pathologic appearance of seven patients with lymphomatoid granulomatosis who had skin lesions when first seen is reviewed. Six patients subsequently developed systemic disease. Although the gross morphology of the skin lesions is variable, the pathology is distinctive. An adequate deep biopsy shows the characteristic lymphohistiocytic infiltrate with variable numbers of atypical cells. Angiodestruction is less evident in the skin compared to other organs. The infiltrate surrounds and invades not only vessels but also nerves and epidermal appendages. The skin biopsy specimen can be differentiated from the lymphomatous infiltrates and Wegener's granulomatosis. Two of the patients who developed systemic disease were diagnosed by skin biopsy but clinicians failed to institute therapy, preferring to wait for other organ involvement. In addition, two patients developed lymphoma, one of which was confirmed at autopsy and one on subcutaneous and bone marrow biopsy 5 years after the initial skin diagnosis. Lymphomatoid granulomatosis can be diagnosed by performing a skin biopsy. Appropriate chemotherapy may result in a high percentage of complete remissions and therefore the dermatopathologist can play an important role in the early diagnosis of this potentially fatal disease.

Proficiency testing in cytology laboratories in Ontario, Canada: a decade of experience. II. Results of initial surveys.

The results of the initial surveys in the cytology proficiency testing of the medical laboratories in the Province of Ontario, Canada, showed a high correlation between the opinions of the testing committee and the participants in the categories of "no abnormal cells," "metaplasia" and forms of "benign atypia." The proportion of times that slides were tested in the categories of dysplasia and malignancy in the surveys increased from 38% by the end of survey 3 to 46% by the end of survey 5. A progressive improvement in the diagnostic accuracy was demonstrated in the categories of malignancy and severe dysplasia while results were more variable in the categories of moderate and mild dysplasia. Several educational activities were initiated following survey 3, including development and circulation of demonstration sets of marked glass slides for repeated circulation to participants as well as copies of a slide/tape presentation describing the program and specific case material.