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T Corona

Publications and source records attributed to T Corona.

At least 19 recordsLinked to original sources
PubMed2000

Cardiovascular dysfunction in multiple sclerosis.

Cardiovascular dysfunction (CD) in multiple sclerosis (MS) is related to involvement of reflex pathways in the brainstem. The battery of CD tests was applied to a group of 40 healthy subjects and 40 patients with MS, divided in 2 subgroups according to the expanded disability status scale (EDSS). The tests included: 1) postural blood pressure changes, 2) postural heart rate changes, 3) heart rate changes on inspiration/forced expiration and 4) ECG R-R interval measurement on the Valsalva maneuver. Both groups were subjected to the functional independence scale (FIM). Imaging studies were reviewed and autonomic dysfunction at other levels was explored. The results showed a statistically significant difference (P < 0.05) in all tests when comparing patients to controls. Tests 1 and 4 had the highest significance, with findings of more severe involvement in patients with a higher EDSS and lower FIM. A correlation was also found between CD and brainstem lesions on MRI (P < 0.01). A significant number of MS patients had evidence of CD. Test 1 may be considered a simple marker, in daily clinical practice, to detect subclinical CD. Subclinical CD is a cause of disability in this group of patients.

Adolescent↗
PubMed1997

Pharmacokinetic study of praziquantel administered alone and in combination with cimetidine in a single-day therapeutic regimen.

A brief therapeutic regimen of praziquantel, reduced to a single day, has been effective for treatment of neurocysticercosis. To study its pharmacokinetic characteristics, levels of praziquantel in plasma were determined for eight healthy volunteers after the administration of three oral doses of 25 mg/kg of body weight given at 2-h intervals, alone and with the simultaneous administration of cimetidine. Each volunteer received both regimens in a randomized crossover design. Blood samples were taken during a period of 12 h, and praziquantel concentration was measured by high-performance liquid chromatography. Levels of praziquantel in plasma remained above 300 ng/ml during a period of 12 h; they increased 100% when cimetidine was jointly administered. Compared with other regimens, the high levels obtained and the longer duration of action seem to be advantageous in prolonging the exposure of the parasites to the drug and support previous clinical experience showing that the treatment of neurocysticercosis with praziquantel can be reduced from 2 weeks to 1 day with the drug still retaining its cysticidal properties. Moreover, simultaneous administration of praziquantel and cimetidine could improve further the efficacy of the single-day therapy for cysticercosis and other parasitic diseases, such as schistosomiasis.

Administration, Oral↗
PubMed1996

Multiple sclerosis in Mexico: hospital cases at the National Institute of Neurology and Neurosurgery, Mexico City.

The frequency and clinical features of multiple sclerosis (MS) at the National Institute of Neurology and Neurosurgery in Mexico City for the period spanning 1984-1993 is presented. Hospital records of patients with clinically diagnosed MS were selected, the frequency and cumulative frequency of this diagnosis were determined and demographic information and clinical features were recorded. It was found that 70% of the patients were women, 25% were professionals, and 95% were of mixed race. The clinical features of our patients and their neuroimages were consistent with those of MS patients in other populations. Importantly, we found that the frequency of MS has almost doubled over the last 10 years. The reason for this phenomenon is discussed as resulting from better health screening, the availability of nuclear magnetic resonance imaging, and the cultural, demographic and dietary changes that have occurred due to the rapid urbanization of our country.

Adolescent↗
PubMed1995

A longitudinal study of the effects of an L-dopa drug holiday on the course of Parkinson's disease.

Drug holidays as treatment in Parkinson's disease (PD) to ameliorate the effects of chronic L-dopa use are a controversial method. They are used in an attempt to resensitize dopamine receptors in the striatum so that L-dopa therapy can be reinstated at lower doses with fewer of the side effects that normally accompany long-term use of the drug. In the present study, 15 patients with PD were submitted to a 7-day L-dopa drug holiday and then followed for 3 years. The effect of the holiday on parkinsonian symptoms and grade of severity of PD was determined using the Webster and the Hoehn and Yahr scales, administered at intervals over the 3-year period. We found that within the first 6 months post-drug-holiday, there was a dramatic improvement in the rating of the symptoms of PD that was statistically significant (p < 0.005). At 12 months, Webster scale scores had risen, but they remained significantly improved (p < 0.05) in comparison with the first postholiday score. This level of improvement was maintained at 24 and 36 months. The grade of severity of the disease stabilized since Hoehn and Yahr scale scores improved for all patients, except one, for the length of the study. One patient left the study after 6 months for unknown reasons. Of the 14 patients that remained, three were given additional drug holidays: two patients at 12 months and one patient at 12, 24, and 36 months. All patients were able to be maintained on a reduced L-dopa dose regimen of 50-70% of their pre-drug-holiday level for the entire 3-year period. In the patients in whom the drug holiday was least beneficial overall, there was a notable reduction in rigidity and in the "on-off" phenomenon. We conclude that an L-dopa drug holiday is a valuable option in the treatment of PD.

Aged↗
PubMed1994

[Electroencephalographic alterations in patients with migraine with and without aura].

We studied 14 patients with migraine with aura (group 1) and 16 patients with migraine without aura (group 2), 92.8% had EEG alterations in ictal and 57% in the interictal phase in group 1. 37.5% had EEG alterations in ictal and 18.7% in the interictal phase in group 2. There was a statistical difference between the two groups and between both phases. We think that patients with EEG alterations during both phase, may have a lower ischemic threshold.

Adolescent↗
PubMed1989

Humoral immune response in patients with cerebral parenchymal cysticercosis treated with praziquantel.

The humoral immune response to treatment with praziquantel (PZQ) was studied in eight patients with parenchymal cerebral cysticercosis (CC). In the serum and in the cerebrospinal fluid (CSF) before, during and after the administration of the drug, the following were quantitated (a) levels of specific anticysticercous antibodies measured in optical densities by the ELISA method; (b) levels of IgG, IgM, IgA and IgE; (c) levels of complement fraction C3, C4; (d) presence of immune complexes; (e) total number of white blood cells in the CSF. It was found that after treatment with PZQ, the level of specific anticysticercous antibodies and the level of IgG rose significantly in the CSF but not in the blood. The levels of the fractions of the complement and the immunoglobulins IgM, IgA and IgE did not change significantly either in the serum or in the CSF. The blood-brain barrier was found ruptured in three patients before therapy and in five patients after the therapy as measured by the albumin index. Nevertheless, the IgG index showed that there was local production of IgG in five patients before treatment and in seven after the end of it. The relative specific antibody index was greater than 1.0 in five patients before therapy and in seven after therapy. This data strongly supports the idea that the specific antibodies are produced intrathecally and are not derived from the serum pool through a ruptured blood-brain barrier. It was concluded that patients with parenchymal CC have an elevation of specific anticysticercous probably due to a combination of a ruptured blood-brain barrier and intrathecal synthesis. The relatively small rupture of the blood-brain barrier and the high IgG and relative specific antibody index suggest that intrathecal synthesis is the most important mechanism. The humoral immune response may be of importance not only in the elimination of the parasite but also in the genesis of the illness.

Adult↗
PubMed1986

A prognostic classification of cerebral cysticercosis: therapeutic implications.

Cerebral cysticercosis is a parasitic infestation with a highly variable prognosis and diverse clinical manifestations. Over the period of two years 51 patients were studied prospectively with this infestation, paying particular attention to the duration and severity of the illness, clinical course, CT findings and therapeutic modalities. Patients with parenchymal cysts or calcification without hydrocephalus had a benign disorder presenting commonly with seizures. This type of infestation usually is long-standing, almost never requires surgical treatment, responds to praziquantel therapy and has a good prognosis. In contrast, patients who present with hydrocephalus, large supratentorial cysts, multiple granulomata with cerebral oedema or with vasculitis and cerebral infarction, have an aggressive, acute or subacute illness, presenting with raised intracranial pressure, gait disturbances, mental changes, seizures, cranial nerve palsies, hemisphere syndromes, chronic meningitis and stroke. This malignant form usually requires surgical therapy, does not respond to praziquantel and may produce a fatal outcome or serious sequelae.

Adolescent↗
PubMed1986

Anticysticercous antibodies in serum and cerebrospinal fluid in patients with cerebral cysticercosis.

Fifty-one cases of cerebral cysticercosis proved by surgery or CT scanning were studied prospectively with the ELISA test in order to detect anticysticercous antibodies in blood and CSF. The ELISA test was also performed for detection of antibodies in 20 control patients who had CSF withdrawn during a myelogram and in 119 serum samples of asymptomatic subjects. We found an overall sensitivity of the ELISA test in the blood of 87% with a specificity of 90%. In the CSF we found a sensitivity of 87% with a specificity of 100%. However, when we compared patients with cerebral cysticercosis of a benign type with patients with cerebral cysticercosis of a malignant type we found a serum sensitivity of 75% for the benign group as compared to 93% of the malignant group. The CSF sensitivity was 80% in the benign group and 93% in the malignant group. This difference was statistically significant.

Adolescent↗
PubMedDate not supplied

Possible association between Taenia solium cysticercosis and cancer: increased frequency of DNA damage in peripheral lymphocytes from neurocysticercosis patients.

Helminths, particularly some Schistosoma species, have been associated with cancer in humans. Neurocysticercosis, produced by cysticerci of the helminth Taenia solium, has been associated with the emergence of brain tumours and haematological malignancies. Local tumours, such as glioblastoma, could be explained by the induction of DNA damage in cells surrounding the cysticercus and chronically exposed to an inflammatory host response. However, systemic effects such as haematological malignancies are not easy to understand. The present work was conducted in Mexico to find out whether DNA damage arises in peripheral lymphocytes in patients with neurocysticercosis. We utilized a highly sensitive technique to analyse chromosomal aberrations, in-situ hybridization with probes against chromosomes 1, 2 and 4, and in addition the blocked-cytokinesis technique was used to determine the formation of micronuclei, a peculiar form of DNA damage. The study was made in lymphocytes from 8 patients before and after the administration of praziquantel, 1 of the 2 drugs used for neurocysticercosis treatment. The frequencies of chromosome aberrations and micronuclei in peripheral blood lymphocytes were higher in the infected patients as compared to those observed both in healthy donors and in the group of patients after praziquantel therapy. Our results suggest that chromosome aberrations induced in peripheral cells during neurocysticercosis could be associated with the development of haematological neoplasias.

Adult↗
PubMedDate not supplied

Diagnosis of reversible versus irreversible cerebral ischemia by the intravenous administration of naloxone.

Naloxone was given as an I.V. bolus of 0.8 mgs to four groups of patients with stroke: 1) 20 patients with C.T. proven cerebral infarcts of longer than 7 days duration; 2) 20 patients with acute cerebral ischemia of less than 24 hours; 3) 5 patients with C.T. proven intracerebral hemorrhage of less than 24 hours, and; 4) 3 patients with hyperacute cerebral ischemia which occurred during the performance of a cerebral angiogram. The patients with established cerebral infarctions of more than 7 days duration and the patients with intracerebral hematomas had no response to intravenous naloxone. Of 20 patients with acute cerebral ischemia of less than 24 hours duration, 7 had prompt, complete and long-lasting recovery. These patients had no subsequent evidence of cerebral infarct by C.T. scanner 48 hours after the onset of the cerebral ischemia and were asymptomatic when discharged. The 3 patients with hyperacute cerebral ischemia secondary to cerebral angiography had a dramatic response to the injection of naloxone. These findings suggest that intravenous naloxone may differentiate reversible versus irreversible cerebral ischemia.

Aged↗
PubMedDate not supplied

[A short praziquantel regimen for the treatment of parenchymatous neurocysticercosis].

OBJECTIVE: Fifteen-day praziquantel therapy for parenchymal neurocysticercosis has been shown to be effective. Plasma and cerebrospinal fluid concentrations of praziquantel peak two hours after administration. Maintenance of high concentrations of the drug for six hours may be an adequate therapy for the disease. METHODS: Thirty patients with parenchymal neurocysticercosis were treated with three oral doses of praziquantel(25 mg/kg) at two-hour intervals. Intramuscular dexamethasone (10 mg/day) was administered for three days after the praziquantel treatment. RESULTS: Cysts disappeared in 21 patients and showed a decrease in number of 30 to 60% in seven patients. Two patients remained without change. Considering the total number of cysts, this therapy showed a 70.7% eradication rate. Two patients had seizures, six reported headache, and nausea was frequently reported. Patients under antiepileptic treatment did not have seizures. CONCLUSION: The cost and duration of treatment with praziquantel were significantly reduced and the inflammation that follow the destruction of the parasite was treated sequentially.

Adult↗
PubMedDate not supplied

[Interferon-beta 1a in relapsing-remitting multiple sclerosis. First report of a Mexican population].

OBJECTIVE: We present the results of a prospective and a longitudinal study of IFN-beta 1a (Rebif) in the treatment of Mexican patients with relapsing-remittin multiple sclerosis (MS). PATIENTS AND METHODS: Twenty five patients were included, all of them fulfilled the diagnostic criteria proposed by Poser, had a clinical evolution of at least 2 years, had 2 to 3 acute attacks of MS in the 12 months preceding study entry and an EDSS < 5.5. Six patients were excluded from the trial, one because of anaphylactic shock, 2 progressed to the chronic form and 3 decided not to continue in the study. These patients were considered as treatment failures and represented 24% of the participants entering the trial. The remaining 19 patients (mean age 29.8, 74% females) completed 2-year follow-up. The mean time of disease duration was 48.8 months. Six million units of IFN-beta 1a were applied thrice weekly, in 8 patients (42%) dosage reduction to 6 millions units twice a week was necessary because of leukopenia or elevation in liver enzymes. RESULTS: In the year before treatment with IFN-beta 1a patients had 2.7 +/- 0.93 acute attacks, after treatment the mean number of acute attacks per year was reduced to 1.94 +/- 2.39 (28.9% reduction). When analyzed by gender there was a 62.9% reduction in acute episodes per year in women and a 27.7% reduction in men (p < 0.05). The most frequent side effects were fatigue, headache, local skin reactions, depressed mood, myalgia, weight variations and somnolence. A few patients developed leukopenia, anemia or elevated liver enzymes. In 31.25% of the patients there was an increase in the number of lesions on MRI, in 31.25% there was a reduction in the number of lesions and in 37.5% no change was noted. CONCLUSION: The best-tolerated dose of IFN-beta 1a was 12 million units/week in women and 18 million units/week in men.

Adjuvants, Immunologic↗
PubMedDate not supplied

[Usefulness of drug holiday in patients with Parkinson's disease of more than 5 years of development].

We studied 15 patients with Parkinson's disease of 40 to 70 years of age; they had more than five years of evolution and of using levodopa. They had "on-off", "wearing-off" phenomena and dyskinesia. The duration of therapy suspension was seven days: they were evaluated daily in the seven days, and every month for six months. The Webster and the Hoehn and Yahr scales were used. Only two patients did not show significant improvement. Thirteen of fifteen patients showed a significant decrease in the Webster scale of up to 8 points. A p value of 0.005 was found at three months which was maintained until the sixth month with a p value of 0.0005; a decrease in this scale was present since the first month. There were no complications following therapy withdrawal. There was a decreased related to depression in most of them and also there was a levodopa dose decrease in seven of them.

Adult↗
PubMedDate not supplied

[POEMS syndrome. Report of a case and review of the literature].

A 47 years old male with POEMS syndrome is presented. His illness started seven months before admission. He was in poor general conditions and had malnutrition. He had cutaneous hyperpigmentation, skin changes, hepatomegaly, edema of the limbs, quadriplegia, myotatic reflexes abolished, hypotrophy of muscular masses and bilateral papilledema. Immunoglobulins IgA and IgM were abnormal. Bone scanning showed multiple lytic lesions. The study of bone marrow showed megaloblastic changes. Electromyography revealed severe neuropathy and biopsy from sural nerve showed severe demyelinization. At first, he showed improvement with steroids; nevertheless he died two months afterwards from possible bronchoaspiration. The autopsy revealed changes compatible with the clinical diagnosis and in addition an adenoma of the hypophysis. We emphasize the importance of POEMS syndrome in the differential diagnosis of polyneuropathies.

Humans↗