PubMed Health⌕ Search

Biomedical subjects

P Vega

Publications and source records attributed to P Vega.

At least 19 recordsLinked to original sources
PubMed2005

Clinical and immunological characteristics of type 1 diabetes mellitus in a northwestern Colombian population.

We underwent a project aimed to define the clinical and immunological characteristics of type 1 diabetes (T1D) in a Colombian population. This was a multicenter and cross-sectional study. Patients were systematically interviewed and their medical records reviewed, using a questionnaire that sought information about demographic, clinical and immunological characteristics. Glutamic acid decarboxylase antibodies (GADA), tyrosine phosphatase antibodies (IA-2A) and insulin antibodies (IAA) were examined by radioimmunoassay. There were 107 patients with T1D. Male:female ratio was 1:1. Half of the patients developed diabetes ketoacidosis at onset. GADA, IA-2A, and IAA were detected in 45%, 40%, and 69% of the cases, respectively. GADA positive patients were older and had a less duration of disease than patients without these autoantibodies (p<0.01). Association between breast feeding with the presence of antibodies or clinical characteristics was not observed. The results highlight some differences of T1D expression according to geographic location and ethnicity. Differences in age at onset and clinical variables may point to an environmental factor or deficient access to health care system. Genetic studies underway will provide important information in this population. These results might help to define public health policies in our population to improve T1D diagnosis, patients' quality of life and their outcome.

Adult↗
PubMed2004

Psychiatric issues in the management of patients with multidrug-resistant tuberculosis.

INTRODUCTION: Psychiatric issues present a challenge in the treatment of patients with multidrug-resistant tuberculosis (MDR-TB). Both baseline psychiatric disorders and development of psychiatric complications related to anti-tuberculosis drugs and psychosocial factors require aggressive management. SETTING: A community-based non-governmental health organization in Lima, Peru. OBJECTIVE: To review the literature for psychiatric complications associated with anti-tuberculosis medications, to describe the incidence and prevalence of depression, anxiety and psychosis among individuals receiving MDR-TB therapy, and to detail the management approach used in this cohort. METHODS: A retrospective case series was performed among the first 75 patients to receive individualized MDR-TB therapy in Lima, Peru, between 1996 and 1999. RESULTS: Baseline depression and baseline anxiety were observed in respectively 52.2% and 8.7% of this cohort. Most individuals with baseline depression experienced improvement of depressive symptoms during the course of TB therapy. The incidence of depression, anxiety and psychosis during MDR-TB treatment was 13.3%, 12.0% and 12.0%, respectively. While the majority of individuals with depression, anxiety and psychosis required psychiatric pharmacotherapy, cycloserine was successfully continued in all but one case. CONCLUSION: Psychiatric comorbidities are not a contra-indication to MDR-TB therapy. Management of psychiatric complications is possible without compromising anti-tuberculosis treatment.

Adult↗
PubMed2003

[GB virus C: lack of association with transaminases levels, CD4 and HIV viral load in aids patients].

OBJECTIVE: To study the prevalence of GBV-C-RNA in sera of HIV-infected patients and determine whether differences in immunological condition and hepatic disease exist between GBV-C positive and negative patients. METHODS: The presence of GBV-C-RNA was determined in sera of 222 HIV-positive patients by semi-automated RT-PCR. A comparison of GBV-C-RNA positive and negative patients was made by studying a series of clinical and analytical parameters. This same comparison was made in particular between those coinfected with HCV and GBV-C and those who only presented GBV-C. RESULTS: Prevalence of GBV-C-RNA was 28.8%. The most frequent hepatotropic virus was HCV, appearing in 71.6% of cases. Coinfection with HCV and HGV was present in 17% and 8.6% only had GBV-C. Patients positive for GBV-C-RNA showed clinical and analytical characteristics similar to those found in GBV-C-RNA negative patients. Among the HCV-GBV-C coinfected and those presenting HGV as the only virus it was observed that the coinfected group presented alterations in transaminases and predominance of parenteral transmission as a risk factor for HIV, whereas the GBV-C group presented normal transaminases and predominance of sexual transmission. No differences were perceived in mean CD4 and HIV-RNA values in both groups. CONCLUSIONS: Being positive for GBV-C in HIV-positive patients does not influence the presence of hepatic disease that in these patients is frequently accompanied by coinfection with other hepatotropic viruses. Moreover, it does not seem to influence the viremia of the HIV nor the CD4 cell counts.

Adolescent↗
PubMed2000

Interferon alfa-2b plus ribavirin for chronic hepatitis C patients who have not responded to interferon monotherapy.

BACKGROUND: The role of combination therapy is poorly defined in chronic hepatitis C patients who are non-responders to interferon. AIM: To assess the efficacy, safety and tolerance of interferon alfa-2b plus ribavirin in chronic hepatitis C patients who do not respond to interferon monotherapy. METHODS: A total of 127 non-responder patients with chronic hepatitis C received 3 mU t.i.w. of interferon alfa-2b plus 1000-1200 mg ribavirin daily for 48 weeks. Effects of therapy were evaluated by serum aminotransferases and hepatitis C virus (HCV) RNA levels. RESULTS: Twenty-nine (23%) patients had an end-of-treatment response. Six months after treatment, 20 (16%) patients were sustained responders. Early loss of HCV RNA was the strongest predictor of a sustained response (P < 0.0001). Remission was also more frequent in patients with genotype 1b (P < 0.02), elevated alanine aminotransferase (P < 0.03) and low gamma glutamiltranspeptidase (P < 0.002). Treatment was discontinued in 21 (17%) patients: in 14 for intolerance and in seven due to side-effects. CONCLUSIONS: Combination therapy with interferon plus ribavirin produced a sustained response in 16% of chronic hepatitis C patients who were non-responders to interferon. This combination was safe and well tolerated.

Adult↗
PubMed2000

Comparison of rizatriptan 10 mg vs. zolmitriptan 2.5 mg in the acute treatment of migraine. Rizatriptan-Zolmitriptan Study Group.

The efficacy and tolerability of rizatriptan (MAXALT) and zolmitriptan (ZOMIG) were compared in a randomized, double-blind, double-dummy, stratified (on prior use of rizatriptan and/or zolmitriptan), placebo-controlled, single attack study in 766 patients. Rizatriptan tended to provide freedom from pain sooner than zolmitriptan (hazard ratio 1.26, P = 0.075), acting within 60 min following dosing. More patients were pain free at 2 h on rizatriptan than on zolmitriptan (43.2% vs. 35.6%, P=0.041), while headache relief at 2 h was similar (70.5% vs. 66.8%). At 2 h, fewer patients on rizatriptan had symptoms of photophobia (35.6% vs. 43.5%, P = 0.029) and nausea (25.2% vs. 32.5%, P=0.046), and more patients on rizatriptan had normal function (45.4% vs. 37.0%, P=0.025) than zolmitriptan. Headache recurred in 28% of patients taking rizatriptan, 29% taking zolmitriptan and 26% taking placebo. Both active treatments were effective compared to placebo and were well tolerated. The most common side-effects with rizatriptan were asthenia/fatigue, somnolence and dizziness, while the most common side-effects with zolmitriptan were asthenia/fatigue and dizziness.

Adult↗
PubMed1999

Long-term re-treatment with interferon and ribavirin combination therapy in patients with chronic hepatitis C who are non-responders to interferon alone: a preliminary study.

We evaluated the efficacy and tolerance of ribavirin and IFN-alpha combination therapy over 12 months in 28 patients who were non-responders to IFN-alpha alone. Of 24 patients who have finished the therapy, 6 (25%) obtained a complete response (normal ALT and negative HCV RNA) at the end of treatment and maintained a sustained response 27% (5/18).

Adult↗
PubMed1997

[The efficacy of interferon alfa treatment in chronic hepatitis C in relation to the serum concentration of RNA-HCV and the viral genotype].

BACKGROUND: To determinate the viral variables (viremia and genotype) and patients variables (route and years of infection, histology, etc) related with response to the treatment with alpha intefferon in patients with chronic hepatitis C. SUBJECTS AND METHODS: We have studied 50 patients with chronic hepatitis C that received an intefferon treatment during a year. In all them it was accomplished a hepatic biopsy before of the beginning of treatment and it was studied the viral load by quantitative PCR (Monitor, Roche) at the beginning of treatment, at four weeks and at the end of treatment. It was determined the HCV genotype by method INNO-LIPA (Boehringer Inghelheim). RESULTS: 8 patients (16%) achieved a complete sustained response during all the follow-up period (13.8 + 1.6 months); 8 patients responded but relapsed when the intefferon was interrupted and 34 patients not responded. The responders had lower viremia (p < 0.032) and HCV RNA negative at the fourth treatment week (p < 0.0082). The genotype 1b was the most frequent, the one which was presenting a smaller percentage of response and it was associated with a higher viremia. Cirrhotic patients were the worse responders. Ex-lDAs were better responders than the others groups, however this difference did not show statistics meaning. CONCLUSIONS: A low pretreatment HCV-RNA level seems to be indicative of a sustained response to IFN, Whereas a high level seems to be indicative of a non sustained response to IFN. Negativization of HCV-RNA at week four is a good indicator of response to intefferon. Genotype 1b is the most frequent and the worse responder. To have 1b genotype, high pretreatment HCV-RNA level and to be viremic at four treatment seems to be indicative of non response.

Adult↗
PubMed1996

[Measurement of total serum IgE by enzyme immunoassay with three commercial reagents].

We measured total serum IgE in 14 patients with allergic diseases and 16 healthy subjects, using three commercial ELISA kits. The correlation of results among the three kits was analyzed using Passing and Bablock regression parameters. Results show that measurements of the different kits do not coincide. One kit shows differences using sera from normal subjects. There is no correlation among kits when using sera from allergic patients. It is concluded that it is not possible to determine exactly the amount of IgE using these kits, specially in subjects with elevated levels.

Adolescent↗
PubMed1995

Dietary fish oil and cytochrome P-450 monooxygenase activity in rat liver and kidney.

Lauric acid hydroxylation and aminopyrine N-demethylation were studied in kidney and liver microsomes from rats treated with fish oil. Different doses of fish oil containing 20% eicosapentaenoic acid and 10% docosahexaenoic acid were provided daily to the rats for seven days. In all the groups studied, the lauric acid metabolism was higher in kidney microsomes and the aminopyrine metabolism in the liver microsomes. Although no effect on the renal cytochrome P-450 concentration was detectable, all four fish oil doses increased the hepatic concentration of cytochrome P-450 by a mean 27%. The higher fish oil doses used increased the renal and hepatic microsomal metabolism of aminopyrine. The lauric acid metabolism was increased by fish oil only in the liver. Fish oil, a known inducer of fatty acid peroxisomal beta-oxidation, also induced microsomal activity. These results show that liver and kidney respond in different ways to dietary factors such as fish oil. In addition, our study would suggest that fish oil increased the activity of two different families of liver cytochrome P-450. The activity of kidney lauric acid 11- and 12-hydroxylation, however, was not modulated by fish oil.

Aminopyrine↗
PubMed1995

Kidney drug metabolizing activities in streptozotocin diabetic rats.

1. Streptozotocin-induced diabetes produced significant changes on the drug metabolizing enzyme machinery of rat kidney microsomes. 2. It reduced the cytochrome P-450 content by 30%, this effect being reversed by insulin therapy. 3. Total androstenedione oxidative metabolism was increased 2.5-fold and insulin treatment partially antagonized this activation. 4. Total testosterone hydroxylase activities were not modified by diabetes nor by insulin but the formation of 2 alpha OH testosterone and 6 beta OH testosterone were distinct in diabetes or insulin treated diabetic rats. 5. Only UDP-glucuronyltransferase activity for PNP was found in kidney microsomes. Diabetes determined a lower UDPGT substrate efficiency not reversed by insulin therapy.

Androstenedione↗
PubMed1993

Comparison of alloxan and streptozotocin induced diabetes in rats: differential effects on microsomal drug metabolism.

1. Liver microsomes from alloxan or streptozotocin diabetic rats displayed differential drug metabolizing abilities in vitro. 2. Only streptozotocin liver microsomes exhibited changes in the cytochrome P-450 normal spectral characteristics. 3. Overall testosterone metabolism was significantly increased in streptozotocin diabetic liver microsomes, whereas it was markedly decreased in alloxan diabetes. Mixed function oxidase activity for aminopyrine was similar. 4. Glucuronidation reaction rates towards morphine, oestrone and p-nitrophenol were also markedly distinct in both models as well as after insulin treatment. 5. Results suggest that diabetogenic agents modify sex related isoenzymes of cytochrome P-450 differently and selectively reduce the synthesis of certain UDP-glucuronyltransferase forms.

Alloxan↗
PubMed1993

Recovery of the extensor digitorum longus muscle in the rat following L4 nerve sectioning.

The purpose of this study was to define the time course and the extent of recovery of muscle weight and tension in the extensor digitorum longus (EDL) muscle following partial denervation in nine-week-old male rats (300 to 325 g). The L4 nerve underwent unilateral sectioning while the opposite side served as a sham-operated control. The muscle weight and tension of the control and the partially denervated group were examined at two (n = 15), eight (n = 15), 12 (n = 15), and 16 (n = 15) weeks after L4 nerve sectioning. The partially denervated muscle weights as a percentage of respective controls were 58.6%, 56.1%, 68.4%, and 61.9% at two, eight, 12, and 16 weeks after L4 nerve sectioning. There was no significant difference (p > 0.05) between these percentages at the respective time intervals. The tetanic tensions compared with their respective matched controls were 14.5%, 32.8%, 50.0%, and 32.4% at these respective time intervals (p < 0.05). The muscle weight (MW) and muscle weight/body weight (MW/BW) of the partially denervated side as a percentage of its contralateral control remained unchanged throughout the duration of the experiment. The twitch tension (Pt), tetanic tension (Po), Pt/Po, and the Po/MW of the partially denervated muscle relative to its matched control increased between the second and the eighth week post-partial denervation (p < 0.05). After the eighth week post-L4 nerve sectioning, there was no further increase in these parameters.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1992

[H2 antagonists as inhibitors of cytochrome P-450 in rat liver: in vitro and in vivo effects].

Cytochrome P-50 is a well known participant in the metabolism of xenobiotics as well as an activator or inactivator of hepatotoxic substances and carcinogenic agents. H2 antagonists, cimetidine, famotidine and ranitidine were used to inhibit cytochrome P-450 in rat liver. After 200 mg cimetidine, 85% inhibition of cytochrome P-450 in vitro and 50% in vivo were demonstrated through demethylation of aminopyrine. Inhibition was further confirmed by differential absorption spectra (Type II). The percentage inhibition obtained with famotidine or ranitidine were lower than those obtained with cimetidine. Inhibition of the microsomal oxidative system by cimetidine could lead to decreased production of superoxide radicals and protection against damage induced by toxic agents activated in the liver.

Administration, Oral↗
PubMed1992

[Gastric metastasis of renal cell adenocarcinoma].

Gastric metastases are rare, usually discovered at autopsy. The most frequent ones are breast and bronchial cancer, as well as malignant melanoma. The case of a patient with upper gastroenterological hemorrhage due to an ulcerated metastasis from a renal cell carcinoma is presented.

Aged↗
PubMed1991

Multiple antigens in the rat visceral yolk sac induce teratogenic antisera.

Preparative isoelectric focusing was used to fractionate the supernatant from a homogenate of day 19 rat visceral yolk sac. Three fractions, of pI ranges 3.5-5.0, 5.0-7.0, and 7.0-9.0, were isolated and used to immunize rabbits, by four or six weekly injections, each containing 5 mg protein. The resulting antisera were all teratogenic when injected into rats on day 9 of gestation, but widely differing potencies were observed. The most potent antiserum was that against yolk sac components focusing in the pI 7.0-9.0 range: An optimum teratogenic dose of 50 mg protein per kg body weight was observed, and a dose of 100 mg/kg was shown to cause 100% embryonic resorption. Antiserum against the fraction focusing in the pI 3.5-5.0 range was the least teratogenic: A significant incidence of embryonic malformation and death was seen only at doses of 600 mg/kg and above. The two fractions that yielded the more teratogenic antisera were refocused over narrower pH ranges, yielding four subfractions in the pI 5.0-7.0 range and eight subfractions in the pI 7.0-9.0 range. Antisera against each of these 12 fractions were raised in rabbits; most of these antisera were shown to be teratogenic, although of differing potencies. It is concluded that the yolk sac contains many antigens that can elicit antibodies with teratogenic and yolk sac-localizing properties.

Animals↗
PubMed1991

[Amyloid colitis].

A patient is reported who had urolithiasis and pyonephrosis of the right kidney. In the terminal phase of his disease he developed chronic diarrhea and hematochezia. Sigmoidoscopy showed changes in the colo-rectal mucosa compatible with ulcerative colitis with moderate activity. Histology demonstrated large amyloid deposits of the AA type in the lamina propia around the vessels and with atrophy and ulceration if the epithelium.

Amyloidosis↗
PubMed1990

Drug metabolism in Octodon degus: low inductive effect of phenobarbital.

1. Differential effects of phenobarbital pre-treatment on liver microsomal drug metabolizing enzymes were registered in Octodon degus. 2. Glucuronidation reaction for morphine was decreased but that for p-nitrophenol was significantly increased. 3. Oxidative reactions such as naphthalene hydroxylation, morphine and aminopyrine N-demethylation were modestly increased. 4. In phenobarbital treated Octodon degus, testosterone metabolic pathways were decreased, not inducible or absent. 5. Spectral studies revealed two binding sites with different affinities for aniline in Octodon degus liver microsomes. 6. The poor phenobarbital induction on drug metabolism in Octodon degus may be a result of deficiency of androgen metabolic pathways associated to drug metabolizing enzymes.

Aminopyrine N-Demethylase↗