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Biomedical subjects

M H Lopes

Publications and source records attributed to M H Lopes.

At least 19 recordsLinked to original sources
PubMed2001

Variability of cork from Portuguese Quercus suber studied by solid-state (13)C-NMR and FTIR spectroscopies.

A new approach is presented for the study of the variability of Portuguese reproduction cork using solid-state (13)C-NMR spectroscopy and photoacoustic (PAS) FTIR (FTIR-PAS) spectroscopy combined with chemometrics. Cork samples were collected from 12 different geographical sites, and their (13)C-cross-polarization with magic angle spinning (CP/MAS) and FTIR spectra were registered. A large spectral variability among the cork samples was detected by principal component analysis and found to relate to the suberin and carbohydrate contents. This variability was independent of the sample geographical origin but significantly dependent on the cork quality, thus enabling the distinction of cork samples according to the latter property. The suberin content of the cork samples was predicted using multivariate regression models based on the (13)C-NMR and FTIR spectra of the samples as reported previously. Finally, the relationship between the variability of the (13)C-CP/MAS spectra with that of the FTIR-PAS spectra was studied by outer product analysis. This type of multivariate analysis enabled a clear correlation to be established between the peaks assigned to suberin and carbohydrate in the FTIR spectrum and those appearing in the (13)C-CP/MAS spectra.

Carbon Isotopes↗
PubMed2000

Quantitation of aliphatic suberin in Quercus suber L. cork by FTIR spectroscopy and solid-state (13)C-NMR spectroscopy.

This work determined that the percentage of suberin in cork may be found by solid-state (13)C cross polarization/magic angle spinning (CP/MAS) NMR spectroscopy and by FTIR with photoacoustic detection (FTIR-PAS) spectroscopy. A linear relationship is found between the suberin content measured through CP/MAS spectral areas and that measured gravimetrically. Furthermore, application of a partial least squares (PLS1) regression model to the NMR and gravimetric data sets clearly correlates the two sets, enabling suberin quantification with 90% precision. Suberin quantitation by FTIR-PAS spectroscopy is also achieved by a PLS1 regression model, giving 90% accurate estimates of the percentage of suberin in cork. Therefore, (13)C-CP/MAS NMR and FTIR-PAS proved to be useful and accurate noninvasive techniques to quantify suberin in cork, thus avoiding the traditional time consuming and destructive chemical methods.

Carbon Isotopes↗
PubMed2000

Latex allergy in health care personnel.

This article presents a summary of literature published in recent years about latex allergy. The first article on allergic reactions associated with latex was published in Britain in 1979. Since then, the number of reported cases has increased. A wide variety of allergic reactions that range from contact dermatitis to anaphylactic shock are described in literature. Conclusions support that health care team members must be well informed about the implications of latex allergy to better help allergic individuals.

Adult↗
PubMed2000

Spectral editing of 13C cp/MAS NMR spectra of complex systems: application to the structural characterisation of cork cell walls.

A mathematical method of obtaining 13C CP/MAS subspectra of single components of a complex system is presented and applied to three- and four-component systems. The method is based on previously reported work that exploits different proton relaxation properties for different domains of an heterogeneous system. However, unlike the original method that obtained subspectra through a trial-and-error approach, the method here presented solves the problem mathematically, thus avoiding the time-consuming and non-rigorous trial-and-error step. The method is applied to mixtures of three and four polymers and to a more complex system: cork cell walls. As expected, as the number of components increases, the sharing of relaxation properties between different components is increasingly probable, either due to incidental coincidence of relaxation times or to specific interactions and intimate mixing of compounds. While this hinders the calculation of the subspectra of single chemical components, it may provide useful information about inter-component interactions. This possibility was demonstrated by the application of this method to cork cell walls. Both three-component and four-component approaches showed that three domains exist in cork cell walls: carbohydrate/lignin matrix, mobile suberin close to (probably bonded to) lignin groups (about 42% w/w) and hindered suberin close to (probably bonded to) carbohydrate-OCH2O groups (about 4% w/w).

Carbohydrates↗
PubMed2000

Composition of suberin extracted upon gradual alkaline methanolysis of Quercus suber L. cork.

The monomeric composition of suberin extracts obtained by gradual alkaline methanolysis of Quercus suber cork was determined by gas chromatography-mass spectrometry (GC-MS). Results show that 1-alkanols and alkanoic and alpha,omega-alkanedioic acids are preferentially removed upon mild alkaline conditions, whereas mid-chain-modified omega-hydroxyalkanoic acids are preferentially removed under stronger alkaline conditions. Saturated omega-hydroxyalkanoic acids are found to be abundant in all suberin extracts. These results are consistent with two distinct suberin fractions with different locations in cork cell walls and/or esterification degrees. It is proposed that these fractions correlate with the two main suberin peaks in the solid state (13)C NMR spectra of cork and suberin extracts. Quantitative GC-MS analysis showed that suberin monomers comprise approximately 30% (w/w) of the suberin extracts, the remaining comprising nonvolatile structures with high M(n) values, as measured by vapor pressure osmometry. The presence of a large fraction of high molecular weight aliphatic structures in suberin extracts is supported by the corresponding NMR spectra.

Gas Chromatography-Mass Spectrometry↗
PubMed1999

Antimutagenicity of a suberin extract from Quercus suber cork.

The possible protective effect of a suberin extract from Quercus suber cork on acridine orange (AO)-, ofloxacin- and UV radiation-induced mutagenicity (bleaching activity) in Euglena gracilis was examined. To our knowledge, the present results are the first attempt to analyse suberin in relation to mutagenicity of some chemicals. Suberin exhibits a significant dose-dependent protective effect against AO-induced mutagenicity and the concentration of 500 micrograms/ml completely eliminates the Euglena-bleaching activity of AO. The mutagenicity of ofloxacin is also significantly reduced in the presence of suberin (125, 250 and 500 micrograms/ml). However, the moderate protective effect of suberin on UV radiation-induced mutagenicity was observed only at concentrations 500 and 1000 micrograms/ml. Our data shows that suberin extract from Q. suber cork possess antimutagenic properties and can be included in the group of natural antimutagens acting in a desmutagenic manner.

Acridine Orange↗
PubMed1999

Very high-resolution 1H MAS NMR of a natural polymeric material.

The use of ultrafast magic angle spinning (> 30 kHz) in tandem with delayed echo acquisition is shown to yield very high-resolution lH MAS NMR spectra of complex natural organic materials. For the first time, very high-resolution 1H MAS NMR spectra are reported for cork and wood components, two natural materials with great economic importance. The effect of the spinning rate on the 1H NMR spectra was evaluated with single-pulse acquisition and delayed-echo acquisition. The delayed-echo acquisition spectra presented linewidths as sharp as 67 and 25 Hz. The narrow peaks, characterised by proton spin-spin and spin-lattice relaxation, were assigned to the isotropic chemical shifts and the general spectral features were shown to correlate with the sample chemical structure. The tentative assignments of cork 1H MAS NMR signals were presented.

Biopolymers↗
PubMed1999

Motor activity of the gallbladder in systemic sclerosis.

OBJECTIVE: We sought to measure gallbladder emptying in scleroderma patients, when stimulated by exogenous cholecystokinin. METHODS: Twenty-eight consecutive scleroderma patients were evaluated. Ten were excluded for the presence of gallstones. Gallbladder motor function was studied in 18 patients and 18 controls, using specific parameters for the quantification of gallbladder emptying dynamics. Resting gallbladder volumes were compared using the Dodds method with real-time ultrasound. Cholecystokinin (CCK)-stimulated gallbladder function (0.02 microg/kg CCK intravenous infusion/30 min) was assessed by a scintigraphic technique using 99mTc-DISIDA. Five patients presented with CREST syndrome, 13 with the diffuse form of scleroderma. Four were men, 14 women (average age = 46.6+/-15.4 yr). Patients and controls were paired by gender, age, and weight. RESULTS: Resting gallbladder volumes were larger in the four men with scleroderma than in the women with this disease (p < 0.03, Mann-Whitney). The mean gallbladder resting volume in scleroderma patients was not different from the mean volume detected among controls (p = 0.25), even when controlling for gender (p = 0.78 for women, p = 0.08 for men), scleroderma disease subtype (p = 0.50), or disease duration (p = 0.48). Latency period, ejection period, ejection rate, or ejection fraction as measured during cholecystokinin-stimulated scintigraphic studies were not significantly different between patients and controls. A trend was detected for reduction of the ejection period in scleroderma women (p = 0.70) when compared with scleroderma men. More than 35% of the scleroderma patients presented biliary lithiasis. CONCLUSIONS: There was no significant difference in gallbladder dynamics measured by a scintigraphic technique in scleroderma patients, compared with controls, when gallbladder motor function was evaluated by intravenous CCK.

Adult↗
PubMed1999

[The most frequent nursing diagnoses in a gynecological admission unit].

Our objective was to identify the most frequent nursing diagnoses in a gynecological admission unit. The defining characteristics were surveyed from the data reported in the nursing case history and the patient files of 30 patients. The nursing diagnoses were found according to the revised NANDA Taxionomy I. The five most frequent nursing diagnoses were: risk for infection (30 cases); risk for pain (24 cases); health-seeking behaviors (11 cases); fear (10 cases) and stress incontinence (5 cases).

Female↗
PubMed1999

[Adoption of standard precautions: a report].

During 1993 and 1994, a recycling program on Standard Precautions was conducted for the nursing personnel at the Women's Health Centre (CAISM). In 1995, an evaluation was obtained through direct observation of these sectors regarding the adoption of these measures, the adequate use, access and availability of gloves and boxes for the disposal of perforating, sharp material. Sixty observations and 232 procedures were reported. One hundred sixty four procedures (71%) adopted these measures and 68 procedures (29%) did not. It was evident that the need to wash hands and not to use needles twice should be emphasized.

Guideline Adherence↗
PubMed1998

Follow-up of 18 patients with human immunodeficiency virus infection and chronic Chagas' disease, with reactivation of Chagas' disease causing cardiac disease in three patients.

A series of 18 patients with chronic Chagas' disease and human immunodeficiency virus infection were followed up for 2 to 66 months (median, 15.5 months). Artificial xenodiagnosis was positive for 81.3% and natural xenodiagnosis was positive for 81.8% of patients for whom they were performed; 81.8% of 11 patients had medium- or high-level parasitemia. Reactivation of Chagas' disease--direct microscopic examination of blood revealing parasites and, clinically, patients presenting with cardiac disease--occurred in three patients (16.7%). Specific antitrypanosomal treatment with benznidazole was effective in reducing the level of parasitemia and improving the clinical condition in three of the four patients treated.

Adult↗
PubMed1998

Reactivation of Chagas' disease in a human immunodeficiency virus-infected patient leading to severe heart disease with a late positive direct microscopic examination of the blood.

We report a human immunodeficiency virus (HIV)-infected man with chronic Chagas' disease who developed a congestive heart failure that could not be clinically controlled. Endomyocardial biopsy revealed severe myocarditis and the xenodiagnosis result was positive, but Trypanosoma cruzi by direct microscopic examination of the blood was found only four months after the symptoms had started. Treatment with benznidazole was effective in reducing parasitemia, stabilizing the clinical status, and controlling tissue damage related to the parasite. Although the finding of T. cruzi trypomastigotes by direct microscopic examination of the blood has been considered the mark of Chagas' reactivation in immunocompromised patients with chronic disease, in this case it was a late finding.

AIDS-Related Opportunistic Infections↗
PubMed1997

[Opinion of alumni about the teaching of nursing diagnosis according to North American Nursing Diagnosis Association].

In accordance to North American Nursing Diagnosis Association (NANDA), nursing diagnosis is a clinical judgement of the individual, family or community answers to the vital process or to the actual or potential health problems. These gives the basis for the intervention selection by which the nurse is responsible. Believing in the importance of nursing diagnosis, its teaching was introduced 4 years ago in the subjects of Woman s Health Assistance and Perinatal Nursing, in the 6o. period of the undergraduate course in nursing at UNICAMP. Aiming at evaluating these experience, we proposed to get the students opinion and obtain subsides to perfect teaching. Teoric teaching of 4 hours was given and it was indicated the basic bibliography. The supervised practical application was developed during 21 hours in a neonatal unit and 45 hours in health centers. At the end of the subjects, 16 students answered a form with closed and open questions. All the students considered valid the study of the nursing diagnoses. Most of the students considered more proper to introduce the teaching in the 3o. semester, when the nursing basic procedures is begun. As to the difficult of learning in the use of diagnoses, 68.7% of the students reported a difficult level higher to 25% and lower to 75%. The students group considers that the study of nursing diagnoses brought modifications in its concept of nursing assistance.

Attitude of Health Personnel↗
PubMed1997

[Educational program in universal precaution measures: a methodological approach].

An updating program on measures of universal precautions (M.U.P.) was developed at the Center of Whole Care of Woman's Health (Centro de Atenção Integral à Saúde da Mulher-CAISM). These measures and the procedures in the case of work accident were published in a booklet. First, servants should be aware of the matter of stress and its influence on the quality of life. Then, updating was carried through encouraging the reflection on the consequences of the non-adoption of M.U.P. The answers to 286 pre-tests and 242 post-tests were analyzed and the results showed a significantly higher index of correct answers (p < 0.01), mainly regarding the appropriate use of glove.

Education, Nursing↗
PubMed1997

[The most frequent nursing diagnoses in an oncology admission unit].

The aim of this paper was to survey the most frequent nursing diagnoses by means of the nursing history and medical procedure in order to help the care provided at the Oncology Nursing Service of Women Health Whole Care (Centro de Atenção Integral à Saúde da Mulher-CAISM). The five most common diagnoses were: risk for infection, risk for altered body temperature, risk for aspiration and colonic constipation of the exchanging pattern, and risk for activity intolerance of the moving pattern. Data collection was based on these patterns. Data predominantly involving social, cultural, psychological and spiritual aspects were hardly interpreted, because they were poorly registered or omitted.

Adolescent↗
PubMed1995

Simultaneous occurrence of acute myocarditis and reactivated Chagas' disease in a patient with AIDS.

Myocarditis is not an uncommon finding in autopsy series of patients with AIDS, although clinically important myocarditis is rarely noted. We describe a 50-year-old woman with AIDS and chronic chagasic megaesophagus, without previous cardiac abnormalities, who experienced reactivation of Chagas' disease, characterized by the finding of Trypanosoma cruzi via direct microscopic examination of the buffy coat, xenodiagnosis, and blood culture; she developed fatal acute myocarditis. Reactivation of Chagas' disease in patients with AIDS has been reported, but in the great majority of cases it has been associated with central nervous system involvement. In areas where Chagas' disease is endemic, reactivation may occur in patients with AIDS.

AIDS-Related Opportunistic Infections↗