PubMed Health⌕ Search

Biomedical subjects

J Castillo

Publications and source records attributed to J Castillo.

At least 73 records · Page 4Linked to original sources

Coherent rho(0) production in ultraperipheral heavy-ion collisions.

The STAR Collaboration reports the first observation of exclusive rho(0) photoproduction, AuAu-->AuAurho(0), and rho(0) production accompanied by mutual nuclear Coulomb excitation, AuAu-->Au*Au*rho(0), in ultraperipheral heavy-ion collisions. The rho(0) have low transverse momenta, consistent with coherent coupling to both nuclei. The cross sections at sqrt[s(NN)]=130 GeV agree with theoretical predictions treating rho(0) production and Coulomb excitation as independent processes.

Journal Article↗

Centrality dependence of high-p(T) hadron suppression in Au+Au collisions at sqrt[s(NN)]=130 GeV.

Inclusive transverse momentum distributions of charged hadrons within 0.2<p(T)<6.0 GeV/c have been measured over a broad range of centrality for Au+Au collisions at sqrt[s(NN)]=130 GeV. Hadron yields are suppressed at high p(T) in central collisions relative to peripheral collisions and to a nucleon-nucleon reference scaled for collision geometry. Peripheral collisions are not suppressed relative to the nucleon-nucleon reference. The suppression varies continuously at intermediate centralities. The results indicate significant nuclear medium effects on high-p(T) hadron production in heavy-ion collisions at high energy.

Journal Article↗

Azimuthal anisotropy of K(0)(S) and Lambda+Lambda production at midrapidity from Au+Au collisions at sqrt[s(NN)]=130 GeV.

We report STAR results on the azimuthal anisotropy parameter v(2) for strange particles K(0)(S), Lambda, and Lambda at midrapidity in Au+Au collisions at sqrt[s(NN)]=130 GeV at the Relativistic Heavy Ion Collider. The value of v(2) as a function of transverse momentum, p(t), of the produced particle and collision centrality is presented for both particles up to p(t) approximately 3.0 GeV/c. A strong p(t) dependence in v(2) is observed up to 2.0 GeV/c. The v(2) measurement is compared with hydrodynamic model calculations. The physics implications of the p(t) integrated v(2) magnitude as a function of particle mass are also discussed.

Journal Article↗

Midrapidity Lambda and Lambda(macro) production in Au+Au collisions at the square root of [s(NN)]=130 GeV.

We report the first measurement of strange (Lambda) and antistrange (Lambda macro) baryon production from square root of [s(NN)]=130 GeV Au+Au collisions at the Relativistic Heavy Ion Collider (RHIC). Rapidity density and transverse mass distributions at midrapidity are presented as a function of centrality. The yield of Lambda and Lambda; hyperons is found to be approximately proportional to the number of negative hadrons. The production of Lambda; hyperons relative to negative hadrons increases very rapidly with transverse momentum. The magnitude of the increase cannot be described by existing hadronic string fragmentation models alone.

Journal Article↗

Molecular signatures of brain injury after intracerebral hemorrhage.

BACKGROUND: The mechanisms of cellular death in the tissue surrounding an intracerebral hemorrhage (ICH) are not defined. OBJECTIVE: To investigate the relationship of markers of excitotoxicity and inflammation to brain injury after ICH. METHODS: A total of 124 consecutive patients with spontaneous ICH admitted within 24 hours of stroke onset were prospectively investigated. The volumes of the initial ICH, peripheral edema on days 3 to 4, and the residual cavity at 3 months were measured on CT scan. Glutamate, cytokines, and adhesion molecules were measured in blood samples obtained on admission. Stroke severity and neurologic outcome were evaluated with the Canadian Stroke Scale. RESULTS: Poor neurologic outcome at 3 months (Canadian Stroke Scale < 7) was observed in 53 patients (43%). Stroke severity and glutamate concentrations (by each increment of 10 micromol/L, odds ratio 1.23; 95% CI 1.09 to 1.41), but not the initial volume of ICH, were independent predictors of poor outcome. In the multiple linear regression analyses, tumor necrosis factor-alpha concentration was correlated (r = 0.83, p < 0.0001) with the volume of perihematoma edema, and glutamate concentrations were correlated (r = 0.78, p < 0.0001) with the volume of the residual cavity. These same results were observed when lobar (n = 58) and deep (n = 66) ICH were analyzed separately. CONCLUSIONS: High plasma levels of proinflammatory molecules within 24 hours of intracerebral hemorrhage onset are correlated with the magnitude of the subsequent perihematoma brain edema, whereas poor neurologic outcome and the volume of the residual cavity are related to increased plasma glutamate concentrations.

Aged↗

Surgical versus non-surgical treatment for carpal tunnel syndrome.

BACKGROUND: Carpal tunnel syndrome is the clinical condition resulting from the entrapment of the median nerve in the wrist. It has been accepted as the most frequent entrapment neuropathy. The most common symptoms are tingling, numbness, and pain in the hand that may radiate to the forearm or shoulder. There may be weakness and atrophy of the thenar muscles associated with sensory loss in the affected fingers. There is no universally accepted therapy for carpal tunnel syndrome. Surgical treatment is widely preferred to non-surgical or conservative therapies for overtly symptomatic patients, while mild cases are usually not treated. OBJECTIVES: The objective of this review is to compare the efficacy of surgical treatment of carpal tunnel syndrome with non-surgical treatment in improving clinical outcome. SEARCH STRATEGY: We searched the Cochrane Neuromuscular Disease Group register for randomised or quasi-randomised trials as well as MEDLINE, EMBASE and LILACS (to July 2001). We checked the bibliographies in relevant papers and contacted the authors to obtain information about other published or unpublished studies. SELECTION CRITERIA: All randomised and quasi-randomised controlled trials comparing any surgical and any non-surgical therapies. DATA COLLECTION AND ANALYSIS: Two reviewers independently assessed eligibility of the trials. MAIN RESULTS: Only one randomised controlled trial was found. It included 22 female patients, 11 allocated to surgical section of the anterior carpal ligament and 11 to splinting for one month. The trial was not blinded and it is not clear if the allocation was properly concealed. Data reported allowed an intention-to-treat analysis on two secondary outcomes. The results favour surgery for both of them. There was a significant clinical improvement at one year follow-up in 10 out of 11 patients allocated to surgery and two out of 11 allocated to splinting (relative risk 5.00, 95% confidence interval 1.41, 17.76). Eight out of 11 patients allocated to splinting required surgery during follow-up, compared with apparently no re operation in the surgical group (relative risk 0.06, 95% confidence interval 0.00, 0.91). REVIEWER'S CONCLUSIONS: Surgical treatment of carpal tunnel syndrome seems to be better than splinting. There is a need for randomised controlled trials comparing surgical and non-surgical therapies for carpal tunnel syndrome, particularly in patients with mild symptoms in whom there is greater uncertainty concerning the balance of risks versus benefit of surgical therapy.

Carpal Tunnel Syndrome↗

[Guidelines for action and diagnosis in atherothrombosis in Spain: ADA Study (Action and Diagnosis in Atherothrombosis)].

OBJECTIVE: The ADA Study was designed to know the usual action guidelines in Spain for the diagnosis and treatment in a cohort of patients who had a recent atherothrombotic event. PATIENTS AND METHODS: Cross-sectional, observational, multicenter epidemiologic study (294 hospitals) with a total of 3,512 patients enrolled. Patients had had an atherothrombotic event in the coronary or cerebral vascular territory in the previous month or were diagnosed of symptomatic peripheral arterial disease within the last 3 months. A total of 237 investigators (155 cardiologists, 113 neurologists, and 79 vascular surgeons) participated in the study. RESULTS: 54.9% of patients in the study had a previous atherothrombotic event. Of these, 63.1% were on antithrombotic therapy; after the second episode, 2.6% of patients were on no preventive therapy. A great disparity and an excessive number of diagnostic tests was found to confirm the diagnosis of the current atherothrombotic event, which is in contrast with a small percentage of patients who had exams performed to confirm or rule out the atherothrombotic involvement in other vascular territories. CONCLUSIONS: An appropriate protocol should be established for the diagnosis and therapy of patients with the likelihood of having clinical manifestations due to an ahterothrombotic event.

Aged↗

Fate of abstracts from the Paris 1995 European Society of Anaesthesiologists meeting.

BACKGROUND AND OBJECTIVE: To assess the publication rate of full papers presented as abstracts at the 1995 meeting of the European Society of Anaesthesiologists, and to assess factors that might predict subsequent full publication. METHODS: All abstracts presented at the meeting and published in the British Journal of Anaesthesia (Suppl 1, 1995) were included. To verify subsequent full publication, a MEDLINE search was performed and validated. We studied the average time from the meeting to publication, the first author's country, the subspeciality, the publishing journal of the full report, the type of presentation (oral or poster), the object of investigation, and the quality of research design and of statistical reporting in the abstract. RESULTS: Of 472 meeting abstracts, 199 (42.2%) were eventually published. The average (+/- SD) delay between meeting and publication was 16.8 (15.6) months (range 24-60 months). Most papers (79.4%) had been published within 3 yr of the meeting. Circulation, pharmacology and intensive care papers had the highest rates of publication. Sixty-three journals attracted papers, with the British Journal of Anaesthesia publishing most (n = 29). No difference in subsequent publication was found between oral and poster presentations. Randomized trials and animal research were more likely to be published. The number of authors or their positions differed between the abstract and the full publication in 145 cases (72.9%); the first author was changed in 43 cases. CONCLUSIONS: Less than half of the abstracts accepted at the 1995 European Society of Anesthesiologists' meeting were subsequently published in journals indexed by MEDLINE in the 3 yr following the meeting. Many changes in authorship occurred between the abstract and the full publication. The study architecture and the object of investigation predicted full publication.

Abstracting and Indexing↗

Headache as a surrogate marker of the molecular mechanisms implicated in progressing stroke.

The mechanism for headache in patients with acute ischaemic stroke are not completely understood. We analysed the relationship between headache and the early worsening of neurological symptoms in patients with acute ischaemic stroke, and we studied the possible biochemical mechanisms implicated. Headache at the onset of ischaemic stroke predicted progression with a sensitivity, specificity, and positive predictive value of 56%, 99%, and 98%, respectively. CSF concentrations of glutamate, Interleukin-6, and NO-m were significantly greater in patients with progressing stroke than in patients with nonprogressing stroke, and these biochemical markers were also significantly higher in patients with headache than in those without headache. Results of this study suggest that headache at the onset of ischaemic stroke is an independent predictor of neurological worsening and we hypothesize that headache might be a surrogate marker of the molecular mechanisms involved in neurological worsening after acute stroke.

Acute Disease↗

Radioprotective effects in vivo of phenolics extracted from Olea europaea L. leaves against X-ray-induced chromosomal damage: comparative study versus several flavonoids and sulfur-containing compounds.

The radioprotective effects of a polyphenolic extract of Olea europaea L. leaves (OL); the flavonoids diosmin and rutin, which are widely used as pharmaceuticals; and the sulfur-containing compounds dimethylsulfoxide (DMSO) and 6-n-propyl-2-thiouracil (PTU) were determined by using the micronucleus test for anticlastogenic activity, evaluating the reduction of the frequency of micronucleated polychromatic erythrocytes (MnPCEs) in bone marrow of mouse before and after X-ray irradiation. With treatment before X-irradiation, the most effective compounds were, in order, rutin > DMSO > OL > PTU > diosmin. These results showed, for the polyphenols studied, a linear correlation (r(2) = 0.965) between anticlastogenic activity and antioxidant capacity. The magnitude of protection with treatment after X-irradiation were lower, and the most effective compounds were, in order, OL > diosmin > rutin; DMSO and PTU lacked radioprotective activity. Therefore, OL is the only substance that showed a significant anticlastogenic activity both before and after X-ray irradiation treatments. Structurally, the free oxygen radicals and lipoperoxyradicals scavenging capacity and, consequently, the anticlastogenic activity of these polyphenolic compounds are based principally on the presence of specific functional groups, mainly catechol groups (rutin, oleuropein, hydroxytyrosol, verbascoside, luteolin), that also increase the stability of the aroxyl-polyphenol radical generated in the above processes.

Animals↗

Effects of several flavonoids on the growth of B16F10 and SK-MEL-1 melanoma cell lines: relationship between structure and activity.

Although flavonoids seem to be capable of acting at all stages of the carcinogenic process, little information is available on their action in melanoma cell lines. The aim of this study was to assess the response of B16F10 and SK-MEL-1 melanoma cell lines to treatment with six different flavonoids after 24 and 72 h of exposure and to relate the response to their structure. We then compared the findings with those for melphalan treatment. When cultures were treated for 24 h, only slight inhibition at the highest concentrations (25 and 50 microM) of tangeretin and luteolin were observed, whereas melphalan caused a dose-related inhibition of growth at all concentrations. Quercetin, hesperetin, 7,3'-dimethylhesperetin and eriodictyol did not produce any effect at 24 h on B16F10 or SK-MEL-1 cells, results which point to the low toxicity of flavonoids. After 72 h of exposure culture growth was inhibited by 7,3'-dimethylhesperetin at 50 microM, but lower concentrations had no effect. Tangeretin was the most effective of the flavonoids in inhibiting B16F10 and SK-MEL-1 cell growth, showing a clear dose-response curve after 72 h. These results suggest that the absence of the C2-C3 double bond on hydroxylated flavonoids results in a loss of effect on both the cell lines, while the higher activity of tangeretin compared with 7,3'-dimethylhesperetin suggests that the presence of at least three adjacent methoxyl groups confers a more potent antiproliferative effect.

Animals↗

Helicobacter pylori stimulates pepsinogen secretion from isolated human peptic cells.

BACKGROUND: Different acid and peptic related gastroduodenal diseases are associated with both increased gastric secretion and Helicobacter pylori infection. Patients with H pylori associated gastritis or duodenal ulcer have increased serum pepsinogen levels which decrease after eradication. The mechanisms of H pylori induced gastric mucosal damage are not completely understood. AIM: To determine the effects of H pylori on pepsinogen secretion from isolated human peptic cells. METHODS: Dispersed human peptic cells were prepared from endoscopically obtained biopsy specimens after collagenase digestion, mechanical disruption, and density gradient centrifugation. H pylori was obtained from gastric biopsies (antrum and body), and cultured in non-selective and selective media. Isolates of H pylori were used at different concentrations (1 - 20 x 10(6) colony forming units (cfu)). RESULTS: H pylori (10(6) - 2 x 10(7) cfu) increased basal pepsinogen secretion in a concentration dependent manner. This stimulus was not observed with Escherichia coli. The increased secretion was in addition to that observed with 0.1 mM histamine and 0.1 mM dibutyryl-cyclic adenosine monophosphate. However, H pylori did not affect either carbamylcholine (0.1-10 microM) or cholecystokinin (1 microM) stimulated pepsinogen secretion. Addition of the nitric oxide synthase inhibitor N(w)-monomethyl-L-arginine (1 mM) inhibited H pylori induced cGMP generation and pepsinogen secretion, which were also reduced in the absence of extracellular calcium. H pylori induced pepsinogen secretion was not affected by the absence/presence of the cagA gene. CONCLUSIONS: H pylori increases pepsinogen secretion from human peptic cells through a calcium and nitric oxide mediated intracellular pathway. This effect is independent of the H pylori virulent cagA gene, and may be a mechanism of H pylori induced gastric mucosal damage.

Adult↗

New concept regarding chest pain due to hypoxia of the internal mammary arteries in more than 1,600 operated patients with cerebral thoracic neurovascular syndrome (CTNVS).

In this article we describe the role of compression of the vertebral, subclavian, internal mammary, internal carotid arteries, brachial plexus and coiling and kinking of the vertebral and basilar arteries, the faulty irrigation of blood supply and oxygen of the cerebellum and basal ganglia and other areas of the brain followed by metabolic processes. Among the effects are: a decrease in the secretion of dopamine at the level of the putamen, which produces the symptoms of symptomatic Parkinson's disease, chorea due to chronic transitory faulty blood supply and oxygen to the caudate nucleus, ballism by hypoxia at the level of sub-thalamic and thalamus nuclei and athetosis in the lenticular nucleus. This compression is caused by hypertrophy of the anterior scalenus muscles and the cervical ribs at the level of the vertebrae C6-C7; by the sternocleidomastoid at the level of the cervical atlas, by the pectoralis minor muscles and coiling and kinking of the vertebral, basilar and the internal carotid arteries. The decreased blood supply to the cerebellum and basal ganglia is the cause of the cerebral thoracic neuro vascular syndrome (CTNVS) and its neurological complications, among which are ipsilateral paralysis, symptomatic Parkinson's disease, functional Alzheimer's disease multiple sclerosis and others. We are presently engaged in genetic studies to widen our understanding of these illness.

Aged↗

[Nasolacrimal stent: modifications to Ho-Young Song's technique].

PURPOSE: To introduce modifications to Song's technique in the treatment of nasolacrimal occlusion by means of a polyuretane stent. MATERIAL AND METHOD: Thirty five polyuretane stents were placed under fluoroscopic guidance in 32 patients diagnosed with total and partial nasolacrimal occlusion. CONCLUSION: Technical success rate was 90%. Sixteen right and nineteen left nasolacrimal systems were probed. The introduction of a guidewire through the lower punctum, the use of a Ritleng guide, a Crawford hook and ocular protectors are modifications of Song's procedure that may help in successfully performing this technique in a fast and easy way.

Adult↗

[Spanish doctoral dissertations on anesthesiology and the scientific publications of their authors].

OBJECTIVES: To determine whether obtaining a doctorate is a factor that promotes the research careers of the authors. To analyze the dissemination of Spanish doctoral theses in anesthesiology by looking at the publications they generate. MATERIAL AND METHODS: The TESEO data base was searched for theses on anesthesiology written between 1976 and June 2001. The Medline database was then searched for publications related to each author's thesis. The search identified papers related to each thesis as well as those in which the thesis director was a coauthor. RESULTS: Two hundred twenty-eight theses (9.12 theses/year) were found. Twenty-four authors were not anesthesiologists. The universities of Barcelona (28), Valencia (24), Navarra (23), Autónoma de Barcelona (21), Complutense de Madrid (18) and Cádiz (18) accounted for most of the theses read. The doctoral degree recipients also co-authored 1,833 publications, as the first authors of 649 articles, of which 216 (33.3%) were published before the corresponding thesis was read. Only 127 articles were related to theses. Ninety-seven authors (42.5%) published no article as first author and 22 (9.6%) accomplished no publication as co-author. The thesis director was listed in 154 of the 228 theses in the TESEO database. In this subgroup, 39 doctoral thesis authors published 58 related articles, with the director included among the co-authors in 41 of them. CONCLUSION: Spain produces few doctoral theses on anesthesiology. Most writers of doctoral theses do not publish the results in journals with international readerships. These findings call into question the efficacy of the doctoral thesis as a factor that promotes research.

Academic Dissertations as Topic↗

d Macro and (3)He macro production in square root of s(NN) = 130 GeV Au+Au collisions.

The first measurements of light antinucleus production in Au+Au collisions at the Relativistic Heavy-Ion Collider are reported. The observed production rates for d macro and (3)He macro are much larger than in lower energy nucleus-nucleus collisions. A coalescence model analysis of the yields indicates that there is little or no increase in the antinucleon freeze-out volume compared to collisions at CERN SPS energy. These analyses also indicate that the (3)He macro freeze-out volume is smaller than the d macro freeze-out volume.

Journal Article↗