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PubMed1984

Is prolonged breast-feeding associated with malnutrition?

The association between duration of breast-feeding and nutritional status was studied in a population-based sample of 802 children aged 12 to 35.9 months in Southern Brazil during 1982. The prevalence of malnutrition (low weight for age, length for age, and weight for length) was smallest in those children breast-fed for 3 to 6 months, but after this age nutritional status appeared to be worse in those breast-fed for longer. Children still being breast-fed at the time of the survey presented with a significantly higher prevalence of low weight for length than those who had been totally weaned, and those receiving breast-plus bottle-feeding presented with intermediate levels. This association could not be explained by a number of possible confounding variables using a multiple logistic regression analysis. These results are also consistent with a controlled trial on supplementary feeding in the Sudan.

Adolescent↗
PubMed1989

An investigation of report bias in a case-control study of pregnancy outcome.

The role of report (recall) bias in case-control studies of possible reproductive hazards was investigated in a study of women who gave birth at the Royal Victoria Hospital, Montreal from September 1983 to May 1985. Women were questioned twice (early in pregnancy; after delivery) about exposures that might influence pregnancy outcome. The two sets of responses of case mothers, control mothers, and mothers of infants of intermediate health status were then compared. Similar inconsistencies in the reporting of 39 exposure variables were common in all three groups, with postdelivery deletion of previous reports more frequent than addition of new information. Changes in reporting were not associated with pregnancy outcome, maternal concern about the baby or maternal sociodemographic characteristics. Odds ratios of exposure estimated from the two sets of data did not differ importantly. Moreover, there was no postdelivery trend to increases, or decreases, in the estimates of the odds ratios. The data do not provide evidence of biased reporting of exposures.

Epidemiologic Methods↗
PubMed2002

Combined hepatocellular-cholangiocarcinoma: a histopathologic, immunohistochemical, and in situ hybridization study.

Combined hepatocellular-cholangiocarcinoma (CHC) forms a small but significant proportion of primary liver carcinomas. However, its diagnostic features are not well established, and this has possibly contributed to the variability in its reported clinical outcome in the literature. Many such tumors with features intermediate between hepatocellular carcinoma and cholangiocarcinoma (CC) may have been considered CC in the past based on positivity for "biliary differentiation" cytokeratins and the lack of availability of highly sensitive and specific hepatocellular markers. The utility of in situ hybridization for albumin mRNA, a recently available sensitive and specific hepatocellular marker, has not been reported in CHC. We investigated 27 CHCs with regard to their histomorphologic spectrum and association of these morphologies with immunohistochemical staining for different cytokeratins (CK7, CK19, and CK20; AE1; Cam 5.2), epithelial membrane antigen, polyclonal carcinoembryonic antigen and alpha-fetoprotein, and in situ hybridization for albumin mRNA. All 27 tumors contained areas morphologically intermediate between hepatocellular carcinoma and CC (transitional-type tumors), and in each case such areas formed at least 25% of the tumor. Nine (33%) tumors showed areas with "antler-like" morphology, a feature not previously described in CHC. Twenty-two of 23 tumors (96%) showed positive signals on in situ hybridization for albumin mRNA. Positivity for both hepatocellular (albumin mRNA) and biliary (keratin immunohistochemical profile) markers confirmed the light microscopic impression of biphenotypic differentiation in these tumors. Immunohistochemical positivity for all cytokeratins (except CK7) and epithelial membrane antigen, as well as the expression of albumin mRNA by in situ hybridization, did not show significant differences between hepatocellular carcinoma and CC-like areas. Based on the cytokeratin profile and results on polyclonal carcinoembryonic antigen/alpha-fetoprotein alone, many such tumors would be classified as CC. However, the positivity for albumin mRNA by in situ hybridization proves that such an interpretation would not have been accurate. Clinically, CHCs showed many differences from pure hepatocellular carcinoma, including the absence of cirrhosis (0 of 27), rarity of serum hepatitis B or C marker positivity (4 of 27), and normal to only mildly elevated serum alpha-fetoprotein levels (median 187 ng/mL). The tumor followed an aggressive clinical course, with overall 3-and 5-year survival rates of 30% and 18%, and in the resected cases of 38% and 24%, respectively.

Adult↗
PubMedDate not supplied

The spotted spleen: CT and clinical correlation in a tertiary care center.

PURPOSE: The goal of our study was to examine the prevalence of multiple hypodense splenic nodules and their associated diagnoses and to correlate CT appearance with clinical presentation and diagnosis. METHOD: Records of all patients undergoing contrast-enhanced CT from July 1994 through September 1997 were reviewed. Charts and CT scans of patients with multiple (more than five) hypodense splenic nodules were then evaluated. RESULTS: During the search period, there were 8,764 patients examined. Multiple hypodense splenic nodules were identified in 45 patients. Sixteen patients had malignant neoplasia as an etiology, with two patients having a benign tumor. Ten patients had an infectious etiology; nine patients had an inflammatory but noninfectious etiology; in eight patients, a diagnosis was not established; five of these patients were followed for > 18 months. CONCLUSION: Multiple hypodense splenic nodules are uncommon. Lymphoma, infection, and sarcoid were the three most common disorders in the symptomatic patient, with infection strongly correlated with a compromised immune system. In the asymptomatic patient, nonlymphomatous metastatic disease, benign tumor, and sarcoid were most common. Although overlap exists between diagnostic groups, lymphoma tends to have larger, more variable nodules, whereas infection tends to occur with smaller, more uniform nodules. Sarcoid is intermediate in appearance.

Adolescent↗
PubMed1998

A 50-year longitudinal study of defense use among inner city men: a validation of the DSM-IV defense axis.

The patterns of use of defense mechanisms by 306 inner-city men were rated from interviews at age 47 and these ratings were analyzed by cluster analysis. Five clusters resulted. The correlates of cluster membership were examined using data from the 50-year longitudinal study of these men. One cluster exhibited the greatest use of mature defenses; the men in this cluster functioned best on all psychosocial and health variables. Two clusters of men used primarily neurotic defenses; these men functioned at an intermediate level on all outcomes. The men in two clusters primarily used immature defenses. The men in one of these clusters used primarily action defenses, whereas the men in the other cluster were the greatest users of projection and fantasy. In general, the men in both these clusters functioned worse than those in the other three. However, the users of action defenses exhibited greater sociopathy, alcohol problems, and marital instability. The findings provide general support for the DSM-IV hierarchy for nonpsychotic defenses, with mature defenses at the top, neurotic defenses in the middle, and action defenses toward the bottom. In particular, the study supports the DSM-IV distinction of action defenses from other immature defenses.

Adaptation, Psychological↗
PubMed2001

New methods for estimating pretest probability in the diagnosis of pulmonary embolism.

The clinical assessment of the probability of pulmonary embolism is a key step in proposed diagnostic strategies for pulmonary embolism, because the interpretation of noninvasive test results is conditional on the pretest probability derived from the presence or absence of clinical factors. The past year has brought important progress in the general area of clinical prediction of pulmonary embolism with the publication of two new simple clinical prediction rules. Each of the prediction rules includes a total of seven clinical variables that, when combined, allow for the categorization of patients into categories of low, intermediate, or high pretest probability of pulmonary embolism. Although these clinical prediction rules are perhaps only slightly better than the estimates of experienced clinicians, they provide an explicit method for estimating the probability of PE as an adjunct to diagnostic testing. Further validation work is now needed to assess how well these new prediction rules perform in settings other than the derivation sites.

Algorithms↗
PubMed1983

Sleep laboratory and performance evaluation of midazolam in insomniacs.

This study evaluated laboratory sleep and performance after placebo, after 5, 10 and 20 mg of midazolam and after 30 mg of flurazepam. EEG recordings showed that 20 mg of midazolam significantly decreased sleep latency and stage 1 sleep, increased stage 2 sleep, and delayed the onset of the first REM period when compared with placebo. Subjective reports from the patients showed that the dose decreased the frequency of awakenings. In the morning, 9 h after drug ingestion, performance on most tests was affected very little by 20 mg of midazolam. However, performance on two psychomotor tests was slightly impaired after 20 mg of midazolam, while a test of free recall was slightly improved. On most variables, 5 mg of midazolam acted like placebo, while 10 mg of midazolam was intermediate between placebo and 20 mg of midazolam. Preliminary data suggest that 20 mg of midazolam may be as efficacious in inducing sleep as 30 mg of flurazepam, but may show fewer performance decrements in the morning.

Adult↗
PubMed1979

Vascular leiomyoblastoma of the stomach -- Observations supporting its origin from Zimmermann's pericyte.

Gastric leiomyoblastoma with small mesenteric metastasis in a 44-year-old man has been studied by light and electron microscopy. Histologically, the tumor, having "epithelioid" tumor cells mixed with spindle leiomyomatous cells, was rich in blood vessels and focally simulated hemangiopericytoma. Electron microscopy revealed the tumor cells in variable stages of differentiation from poorly differentiated polygonal cells to smooth muscular cells. The intermediate cells had numerous cytoplasmic processes which interlocked each other. In addition, an intimate association was noted between the tumor cell processes and the small vessels including capillaries. With the recent characterization of the pericyte as a pluripotent mesenchymal cell that may serve as a precursor to the vascular smooth muscle cell, the present observations support the view that some leiomyoblastomas originate from the pericyte of Zimmermann. Leiomyoblastoma may be placed between hemangiopericytoma and glomus tumor in the spectrum of pericytic tumors.

Adult↗
PubMed1978

Intracellular electrical activity of canine and human gastric smooth muscle.

1. Intracellular recordings were obtained from circular smooth muscle fibres of the canine fundus, corpus, antrum and pylorus as well as from the human corpus and antrum. 2. In the canine stomach, all regions of the stomach except the fundus exhibited spontaneous action potentials. 3. The spontaneous action potential consisted of an upstroke potential and a plateau potential. 4. There were regional differences in the configuration of the plateau potential. Corporal and antral smooth muscle did not normally spike during the plateau potential whereas terminal antral and pyloric muscle usually showed spikes on top of the plateau potential. Near the intermediate sphincter, there was a zone of transition in which oscillations in potential of variable amplitude were superimposed on the plateau potential. 5. The configuration of the action potential of the human stomach was similar to the configuration of the canine action potential when the same region of the stomach was compared. 6. The ionic dependence of the plateau potential was studied in canine stomach in an area where neither oscillations nor spikes occurred. 7. In calcium-free solution, all spontaneous activity stopped. D600 selectively suppressed the size of the plateau potential. 8. Sodium-deficient solution reduced the size of the plateau potential. 9. These results suggest that both calcium and sodium may be involved as current carriers in the generation of the plateau potential.

Action Potentials↗
PubMed1985

Aerial Dispersal of Epiphytic Bacteria over Bean Plants.

Plant canopies are strong sources of bacterial aerosols during sunny days when the leaves are dry. Bacterial concentration, upward flux, and deposition onto exposed petri plates were measured over snap beans during three growing seasons. A net upward flux of bacteria occurred only during the warm part of sunny days, not at night when leaves were wet with dew or when a thermal inversion was present. Aerosol source strength was positively correlated with wind speed. Upward fluxes were higher on days after rain than on days when the soil was dry. Other unidentified sources of variability in source strength probably exist. Canopy-level deposition, apparently due to intermediate-scale transport of bacteria in fairly concentrated clouds, can occur in the early evening.

Journal Article↗
PubMed1988

Contrast-sensitivity functions of W-, X-, and Y-like relay cells in the lateral geniculate nucleus of bush baby, Galago crassicaudatus.

1. This paper represents a continuation of our effort to examine the relationship between the physiology of distinct classes of primate lateral geniculate nucleus (LGN) cells and spatial vision. The present study focuses on modeling the contrast-sensitivity functions (CSFs) of separate LGN cell classes, examining differences in the CSFs of different classes of LGN cells and comparing the results with behaviorally defined CSFs. 2. CSFs to drifting sinusoidal gratings were obtained from single LGN relay cells in the nocturnal primate, Galago crassicaudatus. The CSFs of 14 X-like, 27 Y-like, and 6 W-like cells with standard center-surround organization were well fit by a difference of Gaussians (DOG) model with small residual errors (mean error per data point +/- SEM = 0.008 +/- 0.002). The larger residual errors shown by a few of the Y-like cells were not due to nonlinearity of spatial summation. 3. The CSFs of eight cells that appeared to have nonstandard center-surround organization (primarily, a silent, suppressive surround) were also well fit by the DOG model. 4. The DOG curves that best fitted the data differed considerably between the three groups. As a group, X-like cells had a small center mechanism (Rc = 0.19 degrees) with high sensitivity (Kc = 76.53) and a small, sensitive surround (Rs = 0.71 degrees; Ks = 5.50). These parameters produced CSFs with high cutoff frequencies (Vcutoff = 2.5 c/deg) and low peak sensitivities (CSpk = 6.1) that occurred at 0.8 c/deg. 5. Y-like cells had a large center mechanism (Rc = 0.46 degrees) with low sensitivity (Kc = 21.16) and a large, insensitive surround (Rs = 2.38 degrees; Ks = 0.81). These parameters produced CSFs with lower cutoff frequencies (Vcutoff = 1.2 c/deg) and higher peak sensitivities (CSpk = 12.5) that occurred at 0.2 c/deg. 6. The few W-like cells that responded to gratings well enough to determine a CSF were quite variable. As a group they had a large center mechanism (Rc = 0.38 degrees) with intermediate sensitivity (Kc = 34.55) and a surround with intermediate size and sensitivity (Rs = 1.59 degrees; Ks = 1.59). These produced CSFs with intermediate cutoffs (Vcutoff = 1.6 c/deg) and low peak sensitivities (CSpk = 5.0) occurring at 0.4 c/deg.(ABSTRACT TRUNCATED AT 400 WORDS)

Animals↗
PubMed2005

Outcome predictors for the increasing PSA state after definitive external-beam radiotherapy for prostate cancer.

PURPOSE: To identify predictors of distant metastases (DM) among patients who develop an isolated prostate-specific antigen (PSA) relapse after definitive external-beam radiotherapy for clinically localized prostate cancer. MATERIALS AND METHODS: A total of 1,650 patients with clinical stage T1 to T3 prostate cancer were treated with high-dose three-dimensional conformal radiotherapy. Of these, 381 patients subsequently developed three consecutive increasing PSA values and were characterized as having a biochemical relapse. The median follow-up time was 92 months from the completion of radiotherapy. RESULTS: The 5-year incidence of DM after an established PSA relapse was 29%. In a multivariate analysis, PSA doubling time (PSA-DT; P < .001), the clinical T stage (P < .001), and Gleason score (P = .007) were independent variables predicting for DM after established biochemical failure. The PSA-DT for favorable-, intermediate-, and unfavorable-risk patients who developed a biochemical failure was 20.0, 13.2, and 8.2 months, respectively (P < .001). The 3-year incidence of DM for patients with PSA-DT of 0 to 3, 3 to 6, 6 to 12, and more than 12 months was 49%, 41%, 20%, and 7%, respectively (P < .001). Patients with PSA-DT of 0 to 3 and 3 to 6 months demonstrated a 7.0 and 6.6 increased hazard of developing DM or death, respectively, compared with patients with a DT more than 12 months. CONCLUSION: In addition to clinical stage and Gleason score, PSA-DT was a powerful predictor of DM among patients who develop an isolated PSA relapse after external-beam radiotherapy for prostate cancer. Patients who develop biochemical relapse with PSA-DT < or = 6 months should be considered for systemic therapy or experimental protocols because of the high propensity for rapid DM development.

Adult↗
PubMed1999

Fluctuating estrogen and progesterone receptor expression in brainstem norepinephrine neurons through the rat estrous cycle.

Norepinephrine (NE) neurons within the nucleus tractus solitarii (NTS; A2 neurons) and ventrolateral medulla (A1 neurons) represent gonadal steroid-dependent components of several neural networks regulating reproduction. Previous studies have shown that both A1 and A2 neurons express estrogen receptors (ERs). Using double labeling immunocytochemistry we report here that substantial numbers of NE neurons located within the NTS express progesterone receptor (PR) immunoreactivity, whereas few PRs are found in ventrolateral medulla. The evaluation of ERa and PR immunoreactivity in NE neurons through the estrous cycle revealed a fluctuating pattern of expression for both receptors within the NTS. The percentage of A2 neurons expressing PR immunoreactivity was low on metestrus and diestrus (3-7%), but increased significantly to approximately 24% on proestrous morning and remained at intermediate levels until estrus. The pattern of ERalpha immunoreactivity in A2 neurons was more variable, but a similar increment from 11% to 40% of NE neurons expressing ERa was found from diestrus to proestrus. Experiments in ovariectomized, estrogen-treated and estrogen-plus progesterone-treated rats revealed that PR immunoreactivity in A2 neurons was induced strongly by estrogen treatment, whereas progesterone had no significant effect. The numbers of ERalpha-positive NE neurons were not influenced by steroid treatment. These observations provide direct evidence for PRs in NE neurons of the brainstem and show that cyclical patterns of gonadal steroid receptor expression exist in A2, but not A1, neurons through the rat estrous cycle. The expression of PR in A2 neurons appears to be driven principally by circulating estrogen concentrations. The fluctuating levels of ERalpha and PR expression in these brainstem NE neurons may help generate cyclical patterns of biosynthetic and electrical activity within reproductive neural networks.

Animals↗
PubMed2005

Transcriptional response of human umbilical vein endothelial cells to low doses of ionizing radiation.

We used cDNA microarray hybridization technology to monitor the transcriptional response of Human Umbilical Vein Endothelial (HUVEC) cells to x-rays doses ranging from 2 to 200 cGy. An early time window from irradiation (4h) was selected in order to minimize the effects of the cell cycle blockage eventually induced at high doses of irradiation. Three different gene-clustering algorithms have been used to group the 4134 monitored ORF based on their transcriptional response in function of the irradiation dose. The results show that while few genes exhibit a typical dose-dependent modulation with a variable threshold, most of them have a different modulation pattern, peaking at the two intermediate doses. Strikingly even the lowest dose used (2 cGy) seems to be very effective in transcriptional modulation. These results confirm the physiological relevance of sublethal-dose exposures of endothelial cells and strengthens the hypothesis that alternative dose-specific pathways of radioadaptive response exist in the mammalian cells. 111 genes were found to be modulated at all doses of irradiation. These genes were functionally classified by cellular process or by molecular function. Genes involved in coagulation and peroxidase activity and structural constituent of ribosomes were over-represented among the up-regulated genes as compared with their expected statistical occurrence. Three genes coding for regulatory kinase activities (CDK6; PRCKB1 and TIE) are found down-regulated at all doses of irradiation.

Cells, Cultured↗
PubMed2001

Longitudinal observation of deterioration of Doppler parameters, computerized cardiotocogram and clinical course in a fetus with growth restriction.

We report on a fetus with intrauterine growth restriction detected at 27 weeks' gestation, who was longitudinally followed up until delivery by cesarean section 33 days later (31 + 5 weeks) due to severe decelerations in CTG. Longitudinal Doppler assessment of the umbilical artery (UA), the middle cerebral artery (MCA) and the main branch of the right pulmonary artery (RPA), the ductus venosus (DV) and the left coronary artery was compared to clinical course and computerized CTG. At first presentation (day--33) increased resistance in both the UA and uterine arteries with bilateral notches was found. Absent enddiastolic flow (AED) in the UA was found at day--19 and reverse flow (RED) at day--11. The MCA showed a decreased pulsatility first at day--19 and again at day--11 together with RED in the UA. The RPA initially (day--33) showed increased PI which returned to normal values at day--19 but increased again at day--1, when the DV showed RED and the coronary arteries became visible. The DV was normal until day--11, then its PI began to increase together with occurence of RED in the UA, but reverse flow in the DV occurred only on the eve (day--1) of severe decelerations in CTG. Short-term variability in computerized CTG was stable at 6 to 7 ms, except for an intermediate drop to 4 ms at day--10. Maternal hypertension was found at day--19 and mild preeclampsia developed at day--12. A reduction of fetal movements was noticed at day--5. This report shows that at 29 weeks gestation despite detection of AED resp. RED in the UA a prolongation of pregnancy for 19 resp. 11 days is possible. In addition to abnormal CTG, late signs of fetal deterioration are reverse flow in the DV and visibility of the coronary arteries. The role of increased resistance in the main branches of the pulmonary arteries should be examined in the future.

Adult↗
PubMed2004

[Medication use patterns among elderly people in urban area in Northeastern Brazil].

OBJECTIVE: To identify medication use patterns among elderly people residing in areas with different socioeconomic status in the city of Fortaleza, Brazil. METHODS: A total of 668 elderly (aged 60 years or older) residing in the city of Fortaleza, Ceará, Brazil, selected from a multistage random sampling stratified by socioeconomic status (higher, intermediate, and lower areas), were interviewed in a household survey. Descriptive statistics for dichotomous variables were presented as percent of the respective totals, and those for continuous variables as mean +/- SD. Multivariate analyses were performed to identify factors associated with the use of prescription, non-prescription and inappropriate) drugs. RESULTS: Most (80.3% in the higher area) were on at least one non-prescription drug. More than one third (37.4%) were on at least one non- prescription drug and nearly 20% used at least one inappropriate in the lower area. PD use was associated with advanced age (OR=1.7, 95% CI=1.1-2.8); male sex (OR=0.5, 95% CI=0.3-0.7); health service visits (OR=2.5, 95% CI=1.9-3.1); chronic diseases (OR=4.0, 95% CI=2.5-6.2); and higher socioeconomic status (OR=2.0, 95% CI=1.5-2.6).Non- prescription drug use was associated with disability (OR=1.5, 95% CI=1.1-2.2), and higher socioeconomic status (OR=0.6; 95% CI=0.5-0.8). Inappropriate drugs use was mainly associated with male sex (OR=0.4, 95% CI=0.2-0.8); chronic diseases (OR=2.0, 95% CI=1.2-3.3); and higher socioeconomic status (OR=0.7, 95% CI=0.5-0.9). CONCLUSIONS: The proportions of elderly using prescription, non-prescription and inappropriate drugs were remarkable and inequalities were seen particularly among those from different socioeconomic status. These results emphasize the need for strategies to optimize the access and rationalize the use of drugs for elderly people in Brazil.

Aged↗
PubMed2006

First record and description of metacercariae of Curtuteria arguinae n. sp. (Digenea: Echinostomatidae), parasite of cockles Cerastoderma edule (Mollusca: Bivalvia) in Arcachon Bay, France.

A new Himasthlinae species, Curtuteria arguinae, is described as metacercariae from the cockle Cerastoderma edule (L.), collected at Banc d'Arguin (southwestern France). These metacercariae encysted preferentially in the mantle and also in the foot of cockles. Encysted and chemically excysted metacercariae were studied by light microscopy and scanning electron microscopy, respectively. Excysted metacercariae were elongated and curved ventrally. They bore a 33-spine circumoral collar. Sensory papillae were arranged around the oral sucker and also symmetrically along the ventral surface body, from the collar to the acetabulum. The dorsal and ventral tegument surfaces were densely packed with similar pointed spines. The posterior end of the body was without any spines. Among the Curtuteria species described previously, only Curtuteria haematopodis Smogorjewskaja and Iskova, 1966 had the same number of circumoral collar spines. A 6-yr field survey showed that the cockle population at Banc d'Arguin was subjected to a summer infection of C. arguinae. Curtuteria arguinae phenology of infection is characterized by interannual variability and seasonality (beginning in July-August and maximum in autumn). The first intermediate and final hosts remain unknown.

Animals↗
PubMed1963

PUNCHED CARD PROGRAMMING AND RECORDING TECHNIQUES EMPLOYED IN THE AUTOMATION OF THE WATA.

A system of punched card programming and recording of primate discrimination learning experiments is described to illustrate the application of these techniques to the automation of the discrete trial learning situation, allowing for punched card recording and subsequent digital computer data analyses without intermediate data reduction. The system was also designed to control several potential sources of variability inherent in the conventional WGTA testing mode, including 1) the subject's (S's) motivation to test on each trial, 2) S's attention to the stimuli, and 3) the rate of trial presentation so as to be more under S's control. Reliable techniques of punched card programming and recording are detailed.

Animals↗