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Biomedical subjects

A Arjona

Publications and source records attributed to A Arjona.

At least 19 recordsLinked to original sources
PubMed2001

Evaluation of virus excretion by cells persistently infected with the bovine leukaemia virus (BLV) using monoclonal antibodies.

BACKGROUND: bovine leukaemia virus (BLV) is the causative agent of enzootic bovine leukaemia. Studies in vitro usually require the use of infected cell lines, mostly to produce antigen. Two of the most widely used cell lines are FLK-BLV and BLV-bat2. OBJECTIVE: the dynamics of the excretion of BLV proteins and whole virus by the persistently BLV-infected cell lines mentioned above was studied using an indirect ELISA in combination with eight monoclonal antibodies (mAbs) and cow and rabbit serum. STUDY DESIGN: tissue culture flasks were seeded with different concentrations of cells (13000-67000 cells per cm2, corresponding to 1-5 million cells per 75 cm2 flask) and were studied for 20 days. Samples (1.5 ml) were removed every 24 h and the presence of BLV proteins was determined using an indirect ELISA assay in which the antigen reaction with the monoclonal antibodies was evidenced by peroxidase labeled anti-mouse immunoglobulins. RESULTS: cell line FLK-BLV produced a complete monolayer as early as 4 days after passage, 3 days earlier than BLV-bat2. Using mAbs, the amount of viral proteins in the supernatant showed a cyclic pattern, with two evident peaks at days ca. 8 and 16. These peaks occurred even in the absence of passage or medium change, which causes depletion of essential nutrients and acidity. In comparison to polyclonal serum, mAbs gave more clear and defined values and are useful for determining the dynamics of viral production. CONCLUSION: when aiming for high viral yield, BLV should be harvested between days 6 and 8 after passage, when viral shedding is at its maximum. These results are very useful for preparing antigen for monoclonal antibody production, or for techniques such as ELISA or Western blot.

Animals↗
PubMed2001

Comparative study of PCR as a direct assay and ELISA and AGID as indirect assays for the detection of bovine leukaemia virus.

The choice of a diagnostic method depends on the characteristics of the herd to be analysed. Two herds with different prevalences of enzootic bovine leukaemia were chosen to study the concordance between agar gel immunodiffusion (AGID), enzyme-linked immunosorbent assay (ELISA) and polymerase chain reaction (PCR) methods. PCR, an increasingly used virological method, was performed with four sets of primers, amplifying different genomic regions (env, pol and tax), from DNA extracted either from peripheral blood monocytes (PBMCs) or milk leucocytes. The highest percentage of positive animals was obtained using PCR performed with DNA extracted from PBMCs using primers which amplified either env or pol, followed by PCR using PBMCs and primers which hybridized with tax, then ELISA using serum and finally AGID. The results of PCR were more consistent with PBMCs than when milk leucocytes were used.

Animals↗
PubMed2000

Seroepidemiological survey of infection by feline leukemia virus and immunodeficiency virus in Madrid and correlation with some clinical aspects.

A study of 180 healthy cats found that 15.6% were feline leukemia virus (FeLV) positive, 8.3% were feline immunodeficiency virus (FIV) positive, and 1.1% were FIV and FeLV positive, which corresponded to 30.4, 13.8, and 2.6, of 115 cats with FIV- and FeLV-related symptoms, respectively. Differences were seen in the sexes and ages of the populations studied. Anemia, leukopenia, and lymphopenia were the most frequent hematological abnormalities in infected cats.

Age Distribution↗
PubMed1998

Orthostatic headache.

Explore the source record for details and available documents.

Cerebrospinal Fluid Pressure↗
PubMed1998

[Intracranial hemorrhage with fluid level. A case report without coagulation alterations].

The presence of intracranial hemorrhage with a fluid-blood level in patients receiving anticoagulant medication or with coagulopathy is an infrequent but well-documented complication. We reported a patient with a fluid-blood level with normal haemostasis. A 62-year-old-man was admitted with a left putaminal hemorrhage containing a fluid-blood level, but without abnormal haemostasis. Five months later the patient returned to the hospital because of a transient ischemic attack. A cranial CT demonstrated a hypodensity in the left putamen nucleus and corona radiata. Electrocardiogram revealed atrial fibrillation and a cardiac ultrasonographic examination showed mitral annulus calcification and left atrial enlargement. The finding of intracranial fluid-blood level has been seen in patients with arteriovenous malformations, primary and metastatic neoplasm, radiation-induced necroses, cerebral amyloid angiopathy, intrainfarct hematoma and without any identified aetiology. We suggest that in our patient this disorder was due to a intrainfarct hematoma.

Blood Coagulation↗
PubMed1998

[Intracerebral hemorrhage and treatment with platelet aggregation inhibitors: study of 21 cases].

INTRODUCTION: The place of platelet antiaggregants in the aetiology of intracerebral hemorrhage (IH) has not been extensively studied. OBJECTIVE: To analyze the characteristics of IH in patients treated with platelet antiaggregants and the possible clinical and prognostic differences from other primary IH. PATIENTS AND METHODS: A retrospective study of patients admitted to hospital with primary IH from 1985 to 1997. The cases were IH patients while being treated with platelet antiaggregants. For each case we selected two controls with IH and similar age and IH risk factors. The following data was analyzed: start of clinical condition; type, dose, indication and duration of treatment with antiaggregants; mortality, localization, volume and extension of IH to the ventricles. The last four variables were compared with the control group using the ji squared test (chi 2) and the t student test. RESULTS: 21one patients had a primary IH while being treated with antiaggregants: 20 with salicylates (17 aspirin and 3 riflusal) and one with ticlopidine. The dose of aspirin was 500 mg or less in 90% of the cases. In the group treated with salicylates, this was given for more than 20 months in 90% of the cases. Initially there was no clinical progression in any case. No significant differences were observed between the variable compared, although there was a tendency to greater volume, extension to the ventricles and mortality in the group treated with antiaggregants. CONCLUSIONS: More studies with larger numbers of patients are necessary to be able to confirm the tendencies observed.

Aged↗
PubMed1998

[Prevention and treatment of headache due to intracranial hypotension].

INTRODUCTION: In spite of the large number of authors who have studied headache following lumbar puncture and spontaneous intra-cranial hypotension, many aspects remain little known, and there is still no completely satisfactory non-invasive treatment. DEVELOPMENT: In one group of patients there is an increased risk of post lumbar-puncture headache: adults between 20 and 50 years old, of low body weight and a previous history of chronic bilateral headache. In these patients all possible prophylactic measures should be taken whilst the lumbar puncture is being performed, so as to avoid the onset of headache. Use of modern atraumatic needles of small diameter and with a lateral opening have been shown by many studies to be satisfactory. There are also other manoevres which help to reduce the frequency of post lumbar-puncture headache, such as the insertion and withdrawal of the needle with the bevel parallel to the fibres of the dura mater and reinsertion of the stylet before withdrawing the needle. Once the patient has developed post lumbar-puncture headache, or spontaneous intracranial hypotension, initially treatment with cerebral vasoconstrictors such as oral caffeine may be used. After a period of time (2-4 weeks) which makes spontaneous regression of the headache unlikely, the treatment of choice involves epidural patches. CONCLUSION: Well-designed studies are necessary to demonstrate the efficacy of oral caffeine (and other drugs) in post lumbar-puncture headache.

Algorithms↗
PubMed1997

[Cerebrovascular stroke, the cause of the death of the caliph al-Hakam II].

al-Hakam II was the ninth sovereign in the Hispano-Omeyan dynasty and the second caliph of Spain under the Moors. In the night of the 1st of October 976 he died as the result of a disease that had afflicted him for two years old. Cerebrovascular stroke first manifested as hemiplegia. The disease that afflicted the caliph was called al-'illat alfalichiya, or alfeliche in Castilian Spanish, which means the disease of hemiplegia. The caliph was 61 years old and led a sedentary life and was therefore predisposed to suffer ischemic cerebrovascular events. Climate may have played a role in triggering the stroke. Several authors have found that the incidences of ischemic infarcts and intracranial hemorrhages increase during the winter months and on cold days, particularly in patients under 65. The chronicler of the al-Razi period tells us that heavy snow fell in and around Córdoba in 974 and that the following months saw rain and strong winds. We can deduce that caliph al-Hakam II died of a cerebrovascular event and that, based on the few data available, it is likely that the infarction was ischemic and of atherothrombotic origin. Caliph al-Hakam II moved his household from Madinat al-Zahra' to Alcázar de Córdoba as a result of the "recommendation of his doctors because the cold of the Sierra stirred up his humors". This interpretation is correct according to Arab medicine, which is following the line of the ancient Greeks regarding natural faculties, the elements and their corresponding humors.

Cerebrovascular Disorders↗