Biomedical subjects

Norberto Krivoy

Publications and source records attributed to Norberto Krivoy.

10 recordsLinked to original sources

PubMed2006

Alveolar fluid reabsorption is increased in rats with compensated heart failure.

Alveolar fluid reabsorption (AFR) is important in keeping the air spaces free of edema. This process is accomplished via active transport of Na(+) across the alveolo-capillary barrier mostly by apical Na(+) channels and basolateral Na(+)-K(+)-ATPases. Recently, we have reported that acute elevation of left atrial pressures is associated with decreased AFR in isolated rat lungs. However, the effect of chronic elevation of pulmonary capillary pressure, such as seen in patients with congestive heart failure (CHF), on AFR is unknown. CHF was induced by creating an aorto-caval fistula (ACF) in Sprague-Dawley male rats. Seven days after the placement of the fistula, AFR was studied in the isolated perfused rat lung model. AFR in control rats was 0.49 +/- 0.02 ml/h (all values are means +/- SE) and increased by approximately 40% (0.69 +/- 0.03 ml/h) in rats with chronic CHF (P < 0.001). The albumin flux from the pulmonary circulation into the air spaces did not increase in the experimental groups, indicating that lung permeability for large solutes was not increased. Na(+)-K(+)-ATPase activity and protein abundance at the plasma membrane of distal alveolar epithelial tissue were significantly increased in CHF rats compared with controls. These changes were associated with increased plasma norepinephrine levels in CHF rats compared with controls. We provide evidence that in a rat model of chronic compensated CHF, AFR is increased, possibly due to increased endogenous norepinephrine upregulating active sodium transport and protecting against alveolar flooding.

Adrenalectomy↗

PubMed2006

Ethnic differences in population approach and experience regarding complementary-alternative medicine (CAM).

PURPOSE: The aim of this survey was to characterize one urban Arab population who turns to complementary-alternative medicine (CAM). METHODS: Outpatient participants were selected randomly by their ethnical affiliation. The questionnaire was filled during patient visit to their assigned urban outpatient clinic. The answers to the first two questions determined whether the questionnaire was to be completed or not (if at least one answer was Yes, the questionnaire was completed). RESULTS: More males (19%) seek for CAM in the Arab group in comparison to more females in the Jewish population (27%). Fifteen per cent and 7% of the individuals in the Jewish and Arab groups who used CAM have academic education. Fifty-two per cent and 27% of the Jewish and Arab populations declared themselves seculars, 72% of the Arab individuals declared to be traditionalists-religious-orthodox in their believes in comparison to 47% in the Jewish population. Twenty-eight per cent and 0% in the Jewish and Arab populations, respectively, preferred a conventional doctor (MD) in CAM practice. More than 30% in both populations preferred CAM to be delivered in medical and nursing schools. CONCLUSIONS: Forty per cent and 31% in the Jewish and Arab groups experienced complementary medicine intervention at least once. When comparing people who used complementary medicine to those who did not, it is observed that the percentage of individuals holding academic degrees in the Jewish group is higher than in the Arab interviewed in the group utilizing complementary medicine. Traditionalist-religious-orthodox individuals seek more complementary medicine in the Arab population (72%) in comparison to 47% in the Jewish individuals. Only 17% of the Arab individuals and 19% in the Jewish group knew about the adverse reactions caused by CAM therapies. More than 30% in both ethnic groups were in favor of 'legalizing' complementary medicine.

Adolescent↗

PubMed2006

A fatal case of enoxaparin induced skin necrosis and thrombophilia.

Skin necrosis caused by heparins is a rare complication. We report a case of a 71-yr-old white woman who developed painful diffuse skin lesions, most probably related to enoxaparin treatment. Other causes of skin necrosis, including heparin induced thrombocytopenia, disseminated intravascular coagulation, protein C/protein S deficiencies, anti-phospholipid antibodies, and vitamin K deficiency were less likely in this case. The concomitant combined thrombophilia possibly aggravated the patient's clinical presentation.

Aged↗

PubMed2005

Lamotrigine for neuropathic pain.

Lamotrigine is an antiepileptic drug that stabilizes neural membranes by blocking the activation of voltage-sensitive sodium channels and inhibiting the presynaptic release of glutamate. Full length reports of five open trials and six out of seven randomized controlled trials (plus two abstracts) have demonstrated the efficacy of lamotrigine in the treatment of various forms of neuropathic pain. The present drug profile provides a review of the pharmacologic properties of lamotrigine, the clinical evidence related to its efficacy and safety, and discusses the current and future role of the drug in the treatment of neuropathic pain.

Analgesics↗

PubMed2004

Norepinephrine increases alveolar fluid reabsorption and Na,K-ATPase activity.

The purpose of this study was to determine whether alpha-adrenergic receptor agonists have a role in alveolar fluid reabsorption, via Na,K-ATPase, in the alveolar epithelium. Alveolar fluid reabsorption increased approximately twofold with increasing concentrations of norepinephrine (NE) as compared with control rats. Treatment with the nonselective alpha-adrenergic receptor agonist, octopamine, and the specific alpha(1) agonist, phenylephrine, increased alveolar fluid reabsorption by 54 and 40%, respectively, as compared with control. The specific alpha(1)-adrenergic receptor antagonist, prazosin, inhibited the stimulatory effects of NE by approximately 30%, whereas alpha(2)-adrenergic antagonist, yohimbine, did not prevent the stimulatory effects of NE. The administration of ouabain, Na,K-ATPase inhibitor, prevented the NE-mediated increase in alveolar fluid reabsorption. In parallel with these changes, NE increased Na,K-ATPase activity and protein abundance in alveolar epithelial type II cells via the alpha(1)- and beta-adrenergic receptor. We report here that NE increased alveolar fluid reabsorption via the activation of both alpha(1)- and beta-adrenergic receptors, but not alpha(2)-adrenergic receptors. These effects are due to increased activity and abundance of the Na,K-ATPase in the basolateral membrane of ATII cells.

Adrenergic alpha-Agonists↗

PubMed2004

Antibiotic utilization prevalence: prospective comparison between two medical departments in a tertiary care university hospital.

PURPOSE: The aim of this study was to analyze prospectively antibiotic utilization, comparing two in-patient Internal Medicine units. METHODS: Data on individual antibiotic utilization pattern and antibiotic costs were collected prospectively from hospitalized patient charts over a 12-month period, using the prescription-point prevalence method twice a month, for a total of 24 encounters for each admission unit. RESULTS: The antibiotic volume/patient (number of prescriptions), using the prescription-point prevalence methodology, was 330 and 557 in Internal Medicine B and D, respectively, resulting in 1.29 and 1.25 antibiotic courses/patient for each of the two units, respectively (p = 0.91). Thirty-five percent and 39% of the patients received at least one anti-microbial prescription. The total defined daily dose (DDD) and drug utilization 90% (DU90%) index for the units were 432.7 DDD, DU90% 389.7 and 727.8 DDD, DU90% 660.4, respectively (p = 0.01). The drug cost 90% index (DC90%) placed piperacillin-tazobactam in the first place in both units, while amoxycillin-clavulanic acid was in first place when the DU90% index was applied. CONCLUSIONS: A significant statistical difference was found in the anti-microbial cost analyzes of DDD, DU90% and DC90% indexes of the two units, using the prescription-point prevalence methodology. The intervention of a clinical pharmacology specialist in one of the units was effective in reducing the costs registered in that unit.

Aged↗

PubMed2004

A simple approximation for busulfan dose adjustment in adult patients undergoing bone marrow transplantation.

Busulfan is an alkylating agent used in preparative regimens before bone marrow transplantation (BMT). Busulfan concentrations in plasma, expressed as the area under the concentration-time curve (AUC), were reported to correlate with treatment outcome. Because busulfan is administered in 16 doses of 1 mg/kg every 6 hours for 4 days, the opportunities to "correct" the dose as a consequence of the measured AUC are limited to the 16-dosage protocol. In the present research busulfan pharmacokinetics were prospectively evaluated in 27 adult patients treated according to the above protocol by measuring the first, second, and fifth dose AUC. The pharmacokinetic analysis was based on a noncompartment model for extravascular absorption, but calculations according to a 1-compartment model gave similar results. A simple mathematical approximation allowed prediction of the AUC of the second dose from that of the first and the busulfan concentration at trough. Fifteen patients had the dose adjusted at the fourth dose to obtain an AUC within the "therapeutic window" of 950-1500 microM-min. This procedure was then validated by the measurement of the fifth dose AUC. It appears that this simple pocket calculator method allows a rapid evaluation of the need and the extent of dose adjustment and proved to be a valuable tool to improve busulfan administration in pre BMT treatment.

Adolescent↗

PubMed2004

Severe leukopenia associated with mild hepatotoxicity in an HIV carrier treated with nevirapine.

Nevirapine is a non-nucleoside reverse transcriptase inhibitor used in the treatment of human immunodeficiency virus (HIV)-infected patients and in post-exposure prophylaxis. However, its use has recently been limited because of adverse cutaneous and hepatic effects. We report an HIV-infected woman who developed mild leukopenia as the first sign of a nevirapine-related adverse event, which was followed by skin and hepatic toxicity associated with a more severe leukopenia.

Adult↗

PubMed2003

Patient approach and experience regarding complementary medicine: survey among hospitalized patients in a university hospital.

PURPOSE: To characterize the local population that turns to complementary medicine. METHODS: Participants were selected randomly: Medicine [A] (201 patients); Surgery [B] (100 patients); Control [C] (128 patients). The answers to the first two questions determined whether the questionnaire was to be completed. RESULTS: More females sought complementary medicine treatment, with no significant demographic differences among the groups. Nearly 20% of the subjects had academic education while 43% had completed high school. The results of the 16 significant questions were statistically different when comparing groups C and A (p = 0.025) and B (p = 0.011) respectively. A total of 16%, 12.4% and 9% of the subjects respectively preferred a physician MD as their complementary medicine practitioner and 49% [C], 34% [A] and 29% [B] respectively, favored teaching complementary medicine in medical and nursing schools. CONCLUSIONS: A total of 37% [C], 21% [B] and 27% [A] of the subjects experienced complementary medicine intervention at least once. The percentage of individuals holding academic degrees was higher in the group utilizing complementary medicine than those who did not. Only 21% of C and A groups and 12% of B group knew about adverse reactions to complementary therapies. More than 30% favored 'legalizing' complementary medicine.

Adult↗

PubMed2003

Lamotrigine for intractable sciatica: correlation between dose, plasma concentration and analgesia.

An open trial was conducted to study the potential efficacy of the antiepileptic agent lamotrigine in relieving the sciatic pain and the relationship between lamotrigine dosage, plasma concentration and the clinical response. Subsequent to a 1 week washout period from previous analgesics, lamotrigine dose was titrated on a weekly basis from 25 to 400mg/day and was maintained at that dose for additional 4 weeks. Spontaneous pain, the Short Form McGill Pain Questionnaire (SFMPQ), the Straight Leg Raise (SLR) test, and range of motion of the lumbar spine (leaning foreword, to the affected side) were used to assess lamotrigine efficacy. Lamotrigine plasma concentration was tested at the end of each week during the titration period and at the end of the study. Fourteen patients were enrolled in the study. All outcome measurers improved compared to baseline during the titration period, but reached a statistically significant level of improvement only at the 400mg dose. A linear correlation was found between mean lamotrigine dose, mean plasma concentration and mean weekly spontaneous pain, mean SLR and mean bending the affected side, but not with the SFMPQ score. Study results suggest lamotrigine is a potentially effective and safe compound for the treatment of painful lumbar radiculopathy, and that it is likely to act in a dose- and plasma concentration-dependent fashion.

Adult↗