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At least 1,297 records · Page 72Linked to original sources
PubMed1993

Bacterial factors in the formation of renal scars. An experimental study on the role of Escherichia coli P-fimbriation and hydrophobicity.

A model capable of comparing the effects of bacterial virulence factors on renal scarring in vivo has been developed using the female piglet. By creating, at open surgery, unilateral vesicoureteric reflux (VUR) and quantifying scarring both by uptake of an isotope bound to functioning renal parenchyma and by planimetry of the surface area scarred, the effects of 2 organisms, a P-fimbriate Escherichia coli and an E. coli K1 have been compared. The P-fimbriate E. coli was shown to express P-fimbriae in freshly voided urine, was more hydrophobic and produced smaller scars. This indicates that neither the hydrophobicity nor P-fimbriation of the organism causing urinary tract infection (UTI) is of prime importance for the development of renal scars and is evidence against the "big bang" theory for the development of renal scars. Studies on the association of UTI with VUR showed that infection with both E. coli under study led to VUR on the side contralateral to the side undergoing surgery. It seems likely that a non-specific effect of UTI, such as bladder oedema, is responsible for this acquired VUR. An effect of the 2 bacteria under study on the lower urinary tract was observed in that infection with the P-fimbriate E. coli allowed the retention of an intravesical wax plug, whereas infection with E. coli K1 did not. Epidemiological data have shown that the majority of upper urinary tract infections in children are associated with UTI by P-fimbriate organisms. Such an association may be explained in part by an effect of P-fimbriate bacteria on lower urinary tract function rather than an effect on the upper urinary tract.

Animals↗
PubMed1992

Comparison of responses to sarafotoxins 6a and 6c in pulmonary and systemic vascular beds.

Cardiovascular and pulmonary responses to sarafotoxin (S) 6a and S6c were investigated in the anesthetized cat. Intravenous injections of the peptides in doses of 0.1-1.0 nmol/kg caused decreases or biphasic changes in arterial pressure (AP) and increases in central venous pressure, pulmonary arterial pressure (PAP), and cardiac output (CO). Secondary decreases in CO were observed in response to higher doses, and biphasic changes in systemic (SVR) and pulmonary (PVR) vascular resistances were observed. Under constant-flow conditions, the peptides only increased pulmonary lobar arterial perfusion pressure and lobar vascular resistance. AP responses to S6a, S6c, endothelin (ET)-1, ET-2, vasoactive intestinal contractor (VIC), and Lys7-ET-1 were similar, whereas AP responses to S6b and ET-3 were similar. S6a, S6b, S6c, ET-1, ET-2, ET-3, VIC, Lys7-ET-1, and big ET-1 increased PAP. S6a and S6c increased distal aortic and superior mesenteric arterial (SMA) blood flow and caused biphasic changes at the highest doses. Under constant-flow conditions, S6a and S6c produced dose-dependent biphasic changes in hindquarters perfusion pressure. Changes in SVR and PVR in response to the peptide were not affected by hexamethonium, glyburide, or meclofenamate, indicating that responses are independent of autonomic reflexes, activation of ATP-regulated K+ channels, or release of cyclooxygenase products. In contrast, N-nitro-L-arginine methyl ester decreased hindquarters vasodilator response to S6a and S6c. The present data show that S6a and S6c produce both vasodilation and vasoconstriction in the systemic vascular bed and increase lobar vascular resistance and that hindquarters vasodilator responses are mediated, in part, by the release of endothelium-derived relaxing factor.

Animals↗
PubMed2006

[Diagnosis and treatment of hepatic focal nodular hyperplasia: report of 114 cases].

OBJECTIVE: To explore the diagnosis and treatment of the hepatic focal nodular hyperplasia (FNH). METHODS: The clinical data of 114 patients with FNH proved by the pathology were analyzed retrospectively. RESULTS: FNH occurs as a single node in 98.1%, ranging from 0.9 cm to 15.0 cm in diameter [average, (4.2 +/- 2.2) cm], only 2 patients had more than one FNH nodules. 86.0% of patients with FNH were below 50 years old. 89.5% of patients were asymptomatic. AFP was negative in all patients. Hepatitis B was negative in 4.4% (5/114) of patients. Of these patients, 50 lesions were in the left lobe, 50 in the right lobe, 6 in the mid lobe, and 8 in the caudate lobe. A big central artery was found in 3.5% (4/113) of the lesion in patients by color Doppler ultrasound. CT scan showed transient immediate enhancement in 94.3% (66/70) of patients, with central scar in 10 cases. The demonstration of a central scar in the lesion was very helpful for the diagnosis of FNH. MRI demonstrated early vigorous enhancement in 91.8% (56/61) of patients. It is strong enhancement on arterial phase and slight or obvious enhancement on portal venous phase and slightly delayed enhancement of the central scars in FNH. Eleven cases showed central scar. MRI was more helpful for the diagnosis of FNH using liver specific contrast agents: superparamagnetic iron oxide (SPIO). All patients underwent focus resection, and there was no mortality and severe complication. CONCLUSION: FNH shows some typical clinical and imaging features. We could improve the correct diagnosis rate by comprehensively analyzing the clinical and imaging materials.

Adolescent↗
PubMed1995

[The history of tomography].

It is easily forgotten that not yet a hundred years ago the only way to look into the patients' body was via invasive procedures. Within the year of the discovery of X-rays by Conrad Röntgen the need for three dimensional imaging had been voiced. The driving force behind this development was undoubtedly clinical motivation. Planar X-radiographs were not satisfactory to the clinicians who urged the radiologists to provide them with tomographic images. Between 1910 and 1940, classical tomography has been the product of individuals rather than collective groups. It is only in the mid thirties that scientists found out about each other and started to correspond vigorously. Mayer was the first to suggest in 1914 the idea of tomography. Bocage, Grossman and Vallebona all developed the idea further and built their own equipment. In 1931 Ziedses des Plantes published the most extensive and thorough study on tomography. In the forties and fifties a stagnation is noticed, only further refinements to the existing equipment are carried out. Although Frank and Takahashi published the basic principles of axial tomography in the mid forties, we had to wait for the necessary developments in electronics before Hounsfield was able to develop and commercialize the first axial computer tomography in 1972 (EMI-Scanner). At the time all the big radiology companies rushed into the field and soon, second, third and fourth generation CT scanners became available. Only a few years later a new way of generating images without using ionizing radiation was introduced. Lauterbur and Damadian produced the first low quality images with magnetic resonance, a technique called zeugmatography by its inventors. In 1974 the first images of a living subject were published and initial scepticism was replaced by euphoria. This resulted in the spectacular evolution in Magnetic Resonance that we are now observing. While it is impossible to predict the future, the development of networks, the increase in data acquisition and storage will spread a new light on our specialty. A closer cooperation between radiologists, pathologists and clinicians will undoubtedly be necessary, as well as a partial redefinition of the radiologists task.

History, 20th Century↗
PubMedDate not supplied

[Integrated diagnosis of liver angioma: comparison of Doppler color ultrasonography, computerized tomography, and magnetic resonance].

Hemangiomas are the most frequent benign tumors of the liver which are diagnosed at clinics only when they are very big. Their differentiation from primary or secondary liver tumors is a very difficult step. To investigate the capabilities of color Doppler US, CT and MRI in characterizing liver hemangiomas, we retrospectively examined 27 patients with 35 hemangiomas of the liver, all identified with US from January, 1995, to March, 1996, plus 26 patients with color Doppler US, 23 with dynamic CT and 19 with MR findings; 16 patients had been examined with all imaging techniques. Our gold standard was red blood cell SPECT in 16 patients, clinical-diagnostic follow-up in 8 and surgical specimens in 3 patients. Morphological data, the number, size and segmental site were investigated for all lesions. Doppler US was used to study the qualitative and quantitative data of intralesional color patterns, according to a modified Tanaka's classification, and of intralesional max, systolic velocity and pulsatility index (PI). Dynamic CT was performed with the polyphasic technique, that is unenhanced scans followed by selective, dynamic sequential and delayed scans. Morphological data and dynamic time/density curves of lesion/parenchyma were studied. MRI was performed at 0.5 T with T1-weighted SE (TR/TE 280/18), T2-weighted SE (TR/TE 2000/45-90-120) and T2-weighted fast SE (TR/TE 5000/160) sequences. Dynamic T1-weighted GE sequences were performed after Gd-DTPA bolus injection, using the same times as those of dynamic CT. US showed 1.3 lesion/patient, while CT and MRI showed 1.5 and 1.7 lesion/patient, respectively. No differences were observed in lesion size with the three imaging techniques and there was 78% agreement on segmental site. As for morphological patterns, US had 46% sensitivity, considering medium-small lesions only. Intralesional color signals, with spot and branch patterns, were seen in 6/20 lesions (mean phi; 8.4 cm), with a mean intralesional systolic velocity of 0.30 m/s (1.46 KHz); mean intralesional PI value was 0.83. Color Doppler sensitivity was 23%. Combined B-mode and color Doppler US had 69% sensitivity. The typical CT pattern (ring or globular enhancement with centripetal progression and late hyperdensity) had 66% sensitivity. Hyperintensity on T2-weighted images had 96% sensitivity; Gd-DTPA MRI combined with dynamic CT had 100% sensitivity. In conclusion, the US findings of a suspected hemangioma should be diagnostically integrated with MR studies to make the correct diagnosis.

Adult↗
PubMed1994

ECE-1: a membrane-bound metalloprotease that catalyzes the proteolytic activation of big endothelin-1.

Endothelin-1 (ET-1), a 21-residue vasoactive peptide, is produced in vascular endothelial cells from the 38-residue inactive intermediate big endothelin-1 via a specific cleavage at Trp-21-Val-22. The protease that catalyzes the conversion, endothelin-converting enzyme (ECE), constitutes a potential regulatory site for the production of the active peptide. We report the identification of ECE-1, a novel membrane-bound neutral metalloprotease that is expressed abundantly in endothelial cells in vivo and is structurally related to neutral endopeptidase 24.11 and Kell blood group protein. When transfected into cultured cells that normally secrete only big ET-1, the ECE-1 cDNA conferred the ability to secrete mature ET-1. In transfected cells, ECE-1 processes endogenously synthesized big ET-1 as well as exogenously supplied big ET-1, which interacts with ECE-1 on the cell surface. ECE-1 may provide a target for pharmacological intervention to alter ET-1 production.

Amino Acid Sequence↗
PubMed2004

No-effect level in the mutagenic activity of the drug cyproterone acetate in rat liver. Part II. Multiple dose treatment.

In order to probe for the existence of a no-effect levels for mutations induced by multiple dose treatment with cyproterone acetate (CPA), female lacI-transgenic Big Blue rats were treated daily for 3 weeks with oral doses of 5.0, 1.0 or 0.2mg/kg CPA b.w., respectively. The dose of 5mg/kg CPA b.w. ineffective as a single dose (see part I) increased the mutation frequency by 2.5-fold. Daily treatment with 1.0 and with 0.2 mg/kg CPA b.w. for 3 weeks, however, was not effective indicating that the 1 mg dose represents a no-effect level for multiple dose treatment. The finding that a total dose of 21 x 5 = 105 mg/kg CPA b.w. caused 50% less DNA adducts, but a mutation frequency three-fold higher (data extrapolated from part I) than observed after daily treatment with 5mg/kg CPA b.w. for 21 days points to a crucial role of cell proliferation in mutagenesis by CPA. Our present results, in combination with previous findings, offer a basis to estimate the risk to develop mutations in human liver following treatment with CPA. Previous studies revealed that CPA-DNA adducts are formed in human hepatocytes at lower levels than in those of female rats [Mutat. Res. 395 (1997) 179; Cancer Res. 56 (1996) 4391]. Moreover, an in vitro-study indicated that human hepatocytes in culture do not respond to the mitogenic effect of CPA, while rat hepatocytes did [Cancer Res. 51 (1991) 1143]. We conclude that the risk of humans to develop mutations under treatment with CPA is substantially lower than in the female rat.

Animals↗
PubMed2005

[Historical flashes on prostatic symptoms and urinary retention].

OBJECTIVES: To perform a chronological search about symptoms of bladder outlet obstruction of prostatic origin and some of its treatments. METHODS/RESULTS: Over the years we have been collecting data about the topic from books and journals; we present them in such a way that they can be consulted chronologically. From more than 100 references we have selected the 60 most relevant to our judgment. CONCLUSIONS: Many ideas about the syndrome and the way to solve it have arisen, which vary from one time to another. For most urologists, the main operative complication has always been bleeding, leading to the development of a great number of techniques to avoid it. Infection, the other great complication, prompted that initially surgical maneuvers were performed very fastly and with the small incisions. In addition, big drainages were necessary.

Equipment Design↗
PubMed1974

[The distribution of nuclear and cytoplasmic proteins in the blastoderm of the loach, Misgurnus fossilis L].

The concentration of dry substance (protein) and the dry weight of nuclei, cytoplasm and cells from different blastoderm regions at the early blastula and midgastrula stages were determined by interferentional microscopy. It was shown that at the early blastula stage the dry weight of cells in the basal layer is higher than that in the outer layer. Although the protein concentration in the basal layer cells appears to be somewhat higher, differences in their dry weight are due primarily to the big volume of cytoplasm of the basal layer cells. By the midgastrula stage, the total (nucleus + cytoplasm) protein concentration increases (by 17% in the basal layer cells and by 9% in the outer layer cells) due to the increase of nuclear protein concentration. At the same time dry weight of these cells markedly decreases due to the decrease of their volumes in the process of cell divisions. At the midgastrula stage the epiblast cells have the highest dry weight due to the highest protein concentration in the cytoplasm and the biggest cell volume. The results obtained are discussed with respect to the data on the pattern of accumulation of newly synthesized protein in nuclei and cytoplasm with special reference to the duration of individual cell cycle phases.

Animals↗
PubMed1984

Management of hypertension: risk-benefit ratio.

The justification for drug treatment of mild hypertension rests upon epidemiological data demonstrating an increased risk of heart attack and stroke and a very small number of controlled clinical trials. These data provide a slender basis for mass treatment and leave many vital questions unanswered. The incidence of stroke (and heart attack in some countries) appears to be falling irrespective of antihypertensive therapy. Are historic epidemiological findings still relevant? The level of diastolic blood pressure where risk begins to increase appears to be about 95 mmHg. Ought this also to be the target value for blood pressure reduction? Do thiazide diuretics have added risks and beta-adrenergic blocking drugs added benefits over and above their effect upon blood pressure? If the MRC Hypertension trial turns out to be the last of the big placebo controlled trials in hypertension how shall we assess the effects of new types of drugs upon outcome?

Adrenergic beta-Antagonists↗
PubMed1995

[Evaluation of exposure to toxic factors occurring in the cellulose and paper industry].

The study covered the work environment of a big plant producing sulfate cellulose, paper and paperboard. Measurements of chemical substance concentrations, performed by a local plant laboratory during the years 1976-1991, were analysed with reference to production departments and particular workplaces. Out of 37 substances under study, 16 were found in the air of workplaces. Their concentrations exceeded periodically hygienic standards. The most frequent excess of TLV applied to such compounds as wood dust (including hard beechwood), non-organic dusts containing 2-50% of crystalline silica and below 2% of silica, welding fumes, furfuryl aldehyde, sulfur dioxide, phenol and hydrogen sulfide. A computer-aided registrer of hygienic data facilitated the follow-up of dynamics of exposure to toxic compounds of workers employed at given workplaces.

Air Pollutants, Occupational↗
PubMed1992

A comparison of reported sleep disorders in patients on chronic hemodialysis and continuous peritoneal dialysis.

There are few data about the prevalence and characteristics of reported sleep disorders in chronic dialysis patients and, although insomnia is often used as a marker of uremia, there are few data relating complaints of sleep to adequacy of dialysis. We therefore surveyed 48 hemodialysis (HD) patients, 22 continuous peritoneal dialysis (PD) patients, and 41 healthy control subjects about disordered sleep. The questionnaire included demographic data, questions characterizing the reported sleep problems, and linear analogue scales quantitating the severity of the sleep disturbance and feelings of anxiety, worry, and sadness. Kt/V determinations were also made for each dialysis patient. Fifty-two percent of the HD, 50% of the PD, and 12% of the control subjects reported problems sleeping (P less than 0.001, all dialysis patients v controls). No differences between HD and PD in characteristics of sleep problems were seen. Sleep severity scale results confirmed sleep disorders (7.2 in those with v 0.95 in those without sleep disorders, where 0 = sleep a little problem and 10 = a big problem, P less than 0.001). Caffeine intake (P less than 0.05) and worry (P less than 0.004) were the only factors associated with reported sleep disturbances. Kt/V values (1.4 +/- 0.3) did not predict reported sleep problems. Mean reported hours of sleep per night (5.5 +/- 2 v 5.8 +/- 1.4) and desired hours of sleep per night (8.3 +/- 2 v 7.6 +/- 1.3) were similar among dialysis patients and controls reporting sleep problems. Dialysis patients and controls without self-reported sleep disorders slept a mean of 7.1 +/- 2.4 and 7 +/- 1.1 h/night, respectively.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1996

Female and male personality styles: a typological and developmental analysis.

The personality styles of 137 women and 138 men aged 27 years were examined in an ongoing Finnish longitudinal study in which the participants were first assessed at age 8. Data were collected by means of a mailed questionnaire, personality inventories, and a semistructured interview. Variables covered personality characteristics, life orientation, and behavioral activities. Both women and men fell into two major clusters, the adjusted (3/4) and the conflicted (1/4). Both clusters divided into subclusters; altogether, 7 were extracted for women and men replicating the personality types obtained by J. Block (1971) despite the use of a different methodology in a different culture. The clusters had roots in individuals' emotional and behavioral regulation from the early school years onward, and they also predicted personality characteristics over a period of 6 years when the Big Five personality factors were used as criteria.

Adolescent↗
PubMed1991

Expression of endothelin-like peptide in the nervous system of the marine mollusk Aplysia.

The distribution of endothelin (ET)-like peptide immunoreactivity and mRNA in the nervous system of Aplysia californica was investigated by means of immunocytochemistry and in situ hybridization. Using specific antisera to human endothelin-1 (ET-1) and to the c-terminal peptide of human big endothelin-1 (22-38) (big ET-1), ET-like immunoreactivity was localized to various types of neurons. Immunoreactive nerve fibers for both antisera were prominent throughout the nervous system. Hybridization of radiolabeled complementary RNA probes for human ET-1 or rat endothelin (endothelin-3, ET-3) to paraformaldehyde-fixed, paraffin-embedded sections of various ganglia revealed the presence of a large number of labeled neurons. The number of labeled neurons was higher than those that were immunoreactive for the ET antisera. Preabsorption of the ET antisera with their respective synthetic peptide or hybridization of sections with the sense probes confirmed the specificity of the data. The present study shows that members of the endothelin family may be found in very distant phylogenetic organisms. This conservation suggests a possible role for this peptide as a neurotransmitter and/or neuromodulator in the central nervous systems of diverse species.

Animals↗
PubMed1994

[Anastomosis of the rectum].

The anastomosis between rectal remnant and anal canal with other parts of digestive system, remains a big challenge for surgeons till nowadays. In the years period 173 anastomoses has been done with 21 case (12%) of clinical leaks. According to our experience the technique of continuous extramucosal one layer anastomosis is a good one for high colorectal and ileorectal anastomosis. For low colorectal anastomosis the technique of extramucosal interrupted sutures for posterior and Lembert's suture for anterior wall as single layer have had the lowest incidence of clinical leaks. Low and ultra low anastomoses could be best done with double staptechnique acc. to Knight-Griffen. Our figure of 12% of clinical leaks is rather comparable with published data of others.

Anal Canal↗
PubMed1995

Dying at the best time.

These are the results of two surveys of relatives, and others who knew people who had died, describing events in the year before death and their views on the time of the person's death. Those surveyed were identified from death certificates in England. The main focus is on a sample of 3696 people dying in 1990 in 20 health authorities, with supporting analysis from an earlier national sample of 639 people dying in 1987. Variation in peoples' views about whether an earlier death would have been better is reported, in the context of debate about euthanasia. Spouses were less likely than others to feel that it would have been better if the person had died earlier, and this held true even when controlling for the deceaseds' levels of pain, distress, dependency and age. Spouses were more likely than others to say that a later death would have been better, though not in cases where the deceased was reported as having said they wanted to die sooner. Spouses were influenced by the loss which the death of the person represented for them, being more likely than others to say they missed the person who died a great deal, and feel loneliness was a big problem. Non spouses (children and other relatives of the deceased, friends, neighbours and a few officials) on the other hand were more likely than spouses to say an earlier death would have been better, even when levels of pain, distress, dependency and age were controlled for.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed2005

Practical significance of heterogeneity among BVDV strains: impact of biotype and genotype on U.S. control programs.

In the early 1990s research groups in North America noted that a newly recognized severe acute form of bovine viral diarrhea virus infection, referred to as hemorrhagic syndrome or severe acute BVDV (SA BVDV), was associated with a genetically distinct subgroup of BVDV strains. This new subgroup was named BVDV genotype 2 or BVDV2. All BVDV strains previously characterized in the literature belonged to a separate genotype, BVDV1. However, not all strains identified as BVDV2 were associated with severe acute infections. If I did this deletion, I did not mean to do it. I think it was already here, though. I see there are some other big edits that I did not do; fine. Hollis subsequent surveys of BVDV strains isolated from clinical submissions to diagnostic laboratories and contaminated fetal calf serum suggested that the ratio of BVDV2 to BVDV1 strains in the U.S. approached 50%. Further, while antigenic cross reactivity is seen between BVDV1 and BVDV2 strains, a log or more difference is typically observed in titers against viruses from different genotypes. These observations prompted vaccine manufacturers in North America to produce vaccines against BVDV that contained antigens from both BVDV1 and BVDV2 strains. Under experimental conditions, these new vaccines offered improved protection against type 2 strains, however field data are still insufficient to assess their efficacy in practice. The BVDV genotypes may also be segregated into subgenotypes. Two subgenotypes of both BVDV1 (BVDV1a and BVDV1b) and BVDV2 (BVDV2a and BVDV2b) have been reported in North American. BVDV2a predominates with BVDV2b isolation a rare event. In contrast, BVDV1a and BVDV1b are both commonly isolated. Antigenic differences observed between strains from the BVDV1a and BVDV1b subgenotypes have led to the suggestion that protection may be improved by inclusion of strains from both BVDV1a and BVDV1b in vaccines in addition to BVDV2. The cost to benefit ratio of this proposal is currently a matter of debate.

Animals↗
PubMed2005

A chimpanzee (Pan troglodytes) analogue of cross-national generalization of personality structure: zoological parks and an African sanctuary.

Six personality factors, including five resembling the human Big Five, had previously been identified in a separate group of zoo-housed chimpanzees. Comparability of chimpanzee personality factor structure was examined in two highly contrasting habitats: zoos and a large African sanctuary. Questionnaires for the zoo chimpanzees were in English, while most for the chimpanzees in the sanctuary were in French. Differences between the two settings were sufficiently extensive to make them analogous to cross-national human personality studies. Internal consistencies for five of the six factors did not differ between the two samples. The patterns of correlations between the unit-weighted factors were also similar for the two samples. Data from these two samples were pooled and factor analyzed. The resulting factor structure was then rotated to the factor structure described in the original study of chimpanzee personality. Dominance, Extraversion, Dependability, and Agreeableness had high congruences. Emotionality and Openness did not, but the items that had the highest loadings were consistent with the factors' definitions. Finally, sex and age effects for all factors generalized across habitats.

Adolescent↗