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Biomedical subjects

E Popa

Publications and source records attributed to E Popa.

At least 19 recordsLinked to original sources
PubMed2001

Voltammetric determination of L-cysteine at conductive diamond electrodes.

Boron-doped diamond (BDD) electrodes were used to examine L-cysteine (CySH) oxidation in alkaline media. The results of the voltammetric and polarization measurements showed that at BDD electrodes the overall CySH oxidation reaction is controlled by the initial electrochemical step, i.e., the oxidation of the CyS- electroactive species. The same conclusion was supported by the results of a study of pH effects. Conversely, at glassy carbon (GC) electrodes, the same reaction is controlled by the desorption of the reaction products. These results account for the poor response for CySH determination at GC compared to BDD. It was found that BDD exhibits excellent behavior for CySH determination, clearly outperforming GC. The results demonstrate that measurement of the peak current for CySH oxidation can be used as a basis for simple method for determining CySH in the micromolar concentration range by the use of BDD electrodes.

Cysteine↗
PubMed2000

Selective voltammetric and amperometric detection of uric acid with oxidized diamond film electrodes.

Electrochemically anodized diamond film electrodes were used for selective detection of uric acid (UA) in the presence of high concentrations of ascorbic acid (AA) by differential pulse voltammetry and chronoamperometry. Because the oxidation peak potential for AA is approximately 450 mV more positive than that for UA at anodized diamond electrodes, UA can be determined with very good selectivity. By use of chronoamperometry, linear calibration curves were obtained for UA over the concentration range up to 1 x 10(-6) M in 0.1 M HClO4 solution, with the lowest experimental value measured being 5 x 10(-8) M. This is consistent with the fact that a statistical analysis of the calibration curve yielded a detection limit of 1.5 x 10(-8) M (S/N = 3). AA in less than 20-fold excess does not interfere. The practical analytical utility of the method is demonstrated by the measurement of UA in human urine and serum without any preliminary treatment.

Diamond↗
PubMed1989

Measurement of perception threshold to an electric stimulus using a phase-sensitive technique in normal and diabetic subjects.

To evaluate the functional state of peripheral sensitivity we measured the perception threshold to an electrical stimulus applied deeply at the level of the lower limbs in both diabetic and nondiabetic patients. The data were obtained using a phase-sensitive technique with a sinusoidal applied voltage at 1592 Hz. The test signal applied through needle electrodes was monitored using a current-to-voltage convertor, the current being considered to have two components, one resistive (IR) in phase with the voltage V across the electrodes, and the other capacitive (IC) 90 degrees out of phase. A significantly (p less than 0.001) higher perception threshold was found in diabetic patients than in nondiabetic subjects with all three electrical variables measured: IR, IC and V.

Adolescent↗
PubMed1984

Disappearance rate of insulin antibodies after discontinuing insulin treatment in 42 type 2 (non-insulin-dependent) diabetic patients.

The disappearance rate of insulin antibodies was studied after cessation of insulin treatment which had been given for 3 months to 6 years in 42 Type 2 (non-insulin-dependent) diabetic patients. Insulin antibodies were measured before and 15 days after interruption of insulin treatment, and every 30 days until the disappearance of insulin antibodies. The mean +/- SD value of insulin binding in the entire group before the interruption of insulin treatment was 32 +/- 14%. There was no relationship between the antibody level at that time and the duration of insulin treatment. However, the insulin antibody level was significantly higher in 17 diabetic patients on an insulin dose of greater than 20 U/day (p less than 0.02) than in 25 on an insulin dose of less than 20 U/day (39 +/- 13% versus 28 +/- 12%). A positive correlation was found between initial insulin binding and the time required for it to fall below 10% (r = 0.74). Antibodies were absent 60 days after discontinuing insulin treatment in eight of ten subjects presenting with initial binding of less than 20%. In contrast, in only two of 12 patients with an initial binding of greater than 40% were insulin antibodies detectable 150 days after discontinuation of insulin therapy. Disappearance of insulin antibodies sometimes took up to 1 year and occasionally even more than 2 years.

Aged↗
PubMed1983

Blood glucose and plasma insulin responses to various carbohydrates in type 2 (non-insulin-dependent) diabetes.

The blood glucose and plasma insulin responses to some simple carbohydrates (glucose, fructose, lactose) and some complex ones (apples, potatoes, bread, rice, carrots and honey) were studied in 32 Type 2 (non-insulin-dependent) diabetic patients. Blood glucose and plasma insulin were measured at zero time and then at 15, 30, 60, 90 and 120 min after ingestion of 25 g glucose, fructose or lactose, or 30 g honey, 50 g white bread, 125 g white rice or potatoes, 150 g apples or 260 g carrots. Maximum blood glucose and plasma insulin responses were recorded 60 min after ingestion of each test meal. At this time the increases in blood glucose and in plasma insulin were significantly higher after the more refined carbohydrates (glucose, fructose and lactose) than after the more complex ones (apples, potatoes, rice, carrots and honey, -p less than 0.01). Counting the blood glucose increase after glucose as 100%, the corresponding increases in glycaemia for other carbohydrates were: fructose, 81.3%; lactose, 68.6%; apples, 46.9%; potatoes, 41.4%; bread, 36.3%; rice, 33.8%; honey, 32.4% and carrots, 16.1%.

Aged↗
PubMed1978

Technique of lung ventilation through an injector.

Clinical and experimental evidence that the risks of ventilation through an injector can be diminished if the rate of gas flow in the tracheal probe is kept slow is presented. In practice those inlet devices for oxygen which permit an acceleration of the flow at the end of insufflation give better ventilation. The oxygen and air mixture is more uniform and the distribution is more physiological if there are side holes in the tube; the intake of additional air is then not due to the Bernoulli effect but to the effect of propulsion. Lung ventilation through an injector is worthwhile and is the only possible method in some cases, but it demands skill and care.

Anesthesia↗
PubMed1977

[Bone involvement in labial cancer].

22 patients out of 256 treated for labial carcinoma showed evidence of mandibular involvement. In 6 cases, this involvement was by direct tumour extension, in 4 blood-borne metastases inferior dental and chin veins, and in 11 cases bone involvement occurred via a metastatic lymphadenopathy. The last case was mixed.

Humans↗
PubMed1976

The epidemiology of hyperlipoproteinemia in a Rumanian general population sample. Study of 7,085 cases.

Using a two stages screening method the prevalence in the general population of hyperlipoproteinemias (HLP), separated in the five types proposed by Fredrickson, Levy and Lees, and adopted by WHO has been studied. The study included 7,085 subjects of both sexes, aged 25-65 years, representing 84,52 % of a population taken at random within a district of Bucarest. HLP was found in 1,013 cases, i.e. 14,29 % of the investigated population. 48.37 % were men and 51.63 % women. The prevalence of HLP was lowest in the first decace of age studied (25-35 years) and highest in the last two decades (45-65 years). Overweight was more frequently encountered in these patients (64.46 %) than in the total population (32.3 %). Of the 1,013 cases with HLP, 42.35 % (6.05 % of the total population) were of type IV, 27.05 % (3.86 % of the total population) of type II-b, 22.80 % (3.26 % of the total population) of type II-a, 4.74 % (0.67 % of the total population) of the type III and 3.06 % (0.43 % of the total population) of the type V. 22.70 % of the HLP patients were considered primary familial HLP, 66.54 % primary non-familial HLP and 10.76 % secondary HLP; IN 109 secondary HLP, the most frequently encountered disease was diabetes mellitus (42.20 %), followed by hypothyroidism (24.77 %), alcoholism (12.84 %), obstructive liver diseases (9.17 %), pancreatitis (5.50 %), nephrotic syndrome (2.75 %) and treatment with estrogens and steroids (2.75 %).

Adult↗
PubMed1976

[Comparative clinico-histologic study of metastatic adenopathies in cancer of the lip].

The authors studied the correlation between clinical examination and histological findings in lymph node metastasis in 256 patients suffering from carcinoma of the lip. According to the clinical stage, the following were encountered: a) 84 cases of nodes without any clinical changes (32.8%); b) 140 cases of nodes larger than normal, but mobile (54.6%); c) 32 cases of fixed nodes (12.6%). Lymph node dissection was carried out in 210 patients and histological examination revealed: --in group (a) 61 patients operated): lymph node involvement in 8.9% of cases; --in group (b) (120 cases operated): lymph node involvement in 30% of cases; --in group (c) (29 patients operated): lymph node involvement confirmed in 86.2% of cases. In conclusion, only histological examination provides definite information regarding lymph node involvement, confirming or contradicting pre-operative clinical findings.

Humans↗
PubMedDate not supplied

[Pseudomyxoma peritonei (gelatinous peritonitis )].

UNLABELLED: Pseudomyxoma peritonei (P.P.) is characterised by the presence in the peritoneal cavity of 3 elements--mucinous neoplasic cells, mucinous ascites and diffuses mucinous implants. We analysed the patients treated in our service and we made a literature review. The study is a retrospective analysis on the 1984-2000 period. 6 patients were diagnosed with P.P., 2 females and 4 men, with medial age 63 years (53-75). Clinical findings and biologic analysis were not specific and the imagistic explorers didn't permit the preoperative diagnosis. The patients were submitted to variate surgical procedures, based on the benign (4 cases) or malignant (2 cases) character of the disease and on the origin of the lesions: cystadenoma of the appendix with secondary tumours of the ovary (the 2 females) and, respectively, cystadenoma and cytsadenocarcinoma of the appendix, mucinous paraenteric cyst with pseudomyxoma retroperitonei, mucinous recto-sigmoidian neoplasm (the 4 men). We practiced intraperitoneal chemotherapy with Thio-Tepa in 5 cases (intraoperative in 4 cases) and systemic, with 5-FU and mytomicine, in one case. The operative morbidity and mortality were null. All the patients were follow-up (average 4.2 years). The global 5-year survival rate was 60% (100% in the benign disease and 0% in the malignant form). CONCLUSION: P.P. is a rare disease, still poorly understood. The origin of the disease is the appendix (70-80%) and less frequently the ovary. It was divided in two distinct forms: disseminated peritoneal adenomucinosis and peritoneal mucinous carcinomatosis. The treatment associates radical surgery and intraperitoneal chemohyperthermia, in specialised centres, but the prognosis still remains poor (50-70% 5-year global survival rate).

Aged↗
PubMedDate not supplied

[Merkel cell carcinoma].

Merkel Cell Carcinoma (MCC) is a rare and aggressive neuroendocrine dermal neoplasm. This study is a retrospective outcomes analysis of two cases of MCC with data regarding clinical, histopathological, immunohistochemistry and also surgical, chimio and radiological treatment. MCC is a rare dermal tumors, this tumors are most predictable found on sunexposed sites. Diagnosis is best accomplished by a thorough clinical evaluation coupled with light microscopy and defined panel of immunohistochemical studies which are necessary for the definitive diagnosis of Merkel cell carcinoma (cytokeratins, neuron specific enoiase and chromogranin). A lot of other disease must be included in the differential diagnosis. MCC is an aggressive tumor with local or locoregionale extension and distant spread by hematogen or lymphatic way. Surgical excision of tumor and regional lymphadenectomy is the first step of treatment completed with radiotherapy and chemotherapy bat in advanced studies the rate of local or distant recidives is high.

Aged↗
PubMedDate not supplied

[Conversion in laparoscopic surgery].

AIM: The conversion causes evaluation in dynamics. METHODOLOGY: The study is a retrospective analysis of the conversion to open surgery in 1993-2001 period, indifferently of the moment and the determinant cause. The yearly dynamics of the conversions was divided by operation types and surgeons. There were also analysed the moment and the cause of the conversion. RESULTS: There were realised 3961 laparoscopic operations (by 7 experienced surgeons and a lot of young surgeons), with 244 conversions (6.2%), percentage variable depending of the operation (3.3% in hernioraphies, 5.3% in cholecystectomies, 8.2% in gynecologic procedures, 12.1% in appendectomies, 33% in abdominal esophagus procedures, 33% in splenectomies) and on surgeon (until 0% and 8%); the differences until the surgeons don't depend on their experience and for the same surgeon, the experience accumulation doesn't reduce the conversion rate. The most conversions happen after a simple inspection or a minimal dissection (73.1% in cholecystectomy) caused by the existence of plastron, the discovery of a difficult anatomic situation or of another pathology; more rarely, the conversion happens in the principal time (23.4% in cholecystectomy), doing to hemorrhage, impossible dissection, visceral injury or even at the end of the operation (3.5% in cholecystectomy), doing to hemorrhage, loss piece or calculs. CONCLUSIONS: The conversion rate depends especially on the correctness of the indication of laparoscopic approach and not on the surgeon experience, what proves that it is a moment of surgical maturity. Decide from the beginning, in the moment of the recognition of a difficult situation and not after the occurrence of a complication, modifies neither the morbidity, nor the much discussed hospital stay.

Cholecystectomy, Laparoscopic↗
PubMedDate not supplied

[The therapeutical strategy for locally advanced breast cancer].

As for the other cancers, the strategy of therapy of breast cancers is going to a unitary standardization. In our department between 1984-1999 we are operated 1040 patients with breast cancers, which means 25.3% of all cancers treated. 688 (64.3%) were CMLA, 646 (96.7%) of them were in patients women and 22 (3.3%) men. The mean age was 52.4 years (3-84 years). All patients were divided into two trials and analyzed: retrospectively (A) 312 (46.7%) and prospectively (B) 356 (53.3%) patients, 51.2% of patients was in III and IV TNM stage. The patients from trial B were treated concerning with specific therapeutically protocol, adapted by age, anatomopathological form, volume of tumor, skin or thoracic wall invasion, inflammatory lesions, lymph node invasion and physiological period. The results were: the increase of number of radical surgical interventions, the decrease of the morbidity, the increase of survival and a better quality of life.

Adenocarcinoma↗