An ultra-sensitive electrochemical biosensor using the Spike protein for capturing antibodies against SARS-CoV-2 in point-of-care

This work presents an innovative ultra-sensitive biosensor having the Spike protein on carbon-based screen-printed electrodes (SPEs), for monitoring in point-of-care antibodies against SARS-CoV-2, a very important tool for epidemiological monitoring of COVID-19 infection and establishing vaccination schemes. In an innovative and simple approach, a highly conductive support is combined with the direct adsorption of Spike protein to enable an extensive antibody capture. The high conductivity was ensured by using carboxylated carbon nanotubes on the carbon electrode, by means of a simple and quick approach, which also increased the surface area. These were then modified with EDC/NHS chemistry to produce an amine layer and undergo Spike protein adsorption, to generate a stable layer capable of capturing the antibodies against SARS-CoV-2 in serum with great sensitivity. Electrochemical impedance spectroscopy was used to evaluate the analytical performance of this biosensor in serum. It displayed a linear response between 1.0 ​pg/mL and 10 ​ng/mL, with a detection limit of ∼0.7 ​pg/mL. The analysis of human positive sera containing antibody in a wide range of concentrations yielded accurate data, correlating well with the reference method. It also offered the unique ability of discriminating antibody concentrations in sera below 2.3 ​μg/mL, the lowest value detected by the commercial method. In addition, a proof-of-concept study was performed by labelling anti-IgG antibodies with quantum dots to explore a new electrochemical readout based on the signal generated upon binding to the anti-S protein antibodies recognised on the surface of the biosensor. Overall, the alternative serologic assay presented is a promising tool for assessing protective immunity to SARS-CoV-2 and a potential guide for revaccination.

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An ultra-sensitive biosensor for detection of low levels of antibodies against SARS-CoV-2.

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Highly conductive substrate with adsorbed protein S and point-of-care capability.

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Application to human sera samples and good correlation with commercial method.

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Electrochemical impedance readings with an iron-based redox probe.

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Alternative electrochemical impedance readings with anti-IgG labelled with quantum dots.

Improvement of Glycaemia and Endothelial Function by a New Low-Dose Curcuminoid in an Animal Model of Type 2 Diabetes

Curcumin has been suggested as a promising treatment for metabolic diseases, but the high doses required limit its therapeutic use. In this study, a new curcuminoid is synthesised to increase curcumin anti-inflammatory and antioxidant potential and to achieve hypoglycaemic and protective vascular effects in type 2 diabetic rats in a lower dose. In vitro, the anti-inflammatory effect was determined through the Griess reaction, and the antioxidant activity through ABTS and TBARS assays. In vivo, Goto-Kakizaki rats were treated for 2 weeks with the equimolar dose of curcumin (40 mg/kg/day) or curcuminoid (52.4 mg/kg/day). Fasting glycaemia, insulin tolerance, plasma insulin, insulin signalling, serum FFA, endothelial function and several markers of oxidative stress were evaluated. Both compounds presented a significant anti-inflammatory effect. Moreover, the curcuminoid had a marked hypoglycaemic effect, accompanied by higher GLUT4 levels in adipose tissue. Both compounds increased NO-dependent vasorelaxation, but only the curcuminoid exacerbated the response to ascorbic acid, consistent with a higher decrease in vascular oxidative and nitrosative stress. SOD1 and GLO1 levels were increased in EAT and heart, respectively. Altogether, these data suggest that the curcuminoid developed here has more pronounced effects than curcumin in low doses, improving the oxidative stress, endothelial function and glycaemic profile in type 2 diabetes.

Establishing a governance threshold in small-scale fisheries to achieve sustainability

The lack of effective governance is a major concern in small-scale fisheries. The implementation of governance that encompasses the three pillars of sustainability (social, economic, and ecological) is still a worldwide challenge. We examined nine stalked barnacle fisheries (Pollicipes pollicipes) across Southwest Europe to better understand the relationship between governance elements and sustainability. Our results show that nested spatial scales of management, the access structure, co-management, and fisher's participation in monitoring and surveillance promote sustainability. However, it is not the mere presence of these elements but their level of implementation that drives sustainability. Efforts should be placed in the accomplishment of a minimum combination of local scales of management, access rights through individual quotas, instructive-consultative co-management and functional participation. Surpassing this threshold in future governance structures will start to adequately promote social, economic and ecologically sustainability in small-scale fisheries.

Sleep quality and memory function in healthy ageing

OBJECTIVE

To study the relationship between sleep quality and memory in healthy ageing.

METHODS

The study included 99 people older than 50 years (69 women and 30 men; mean age, 68.74±7.18 years) with no associated diseases. Patients completed digital versions of the Word Learning and Visual Paired Associates tests and the Pittsburgh Sleep Quality Index questionnaire to assess the quality of sleep.

RESULTS

Pittsburgh Sleep Quality Index score was negatively correlated with Visual Paired Associates and Word Learning test performance. Performance in these 2 memory tests decreased in line with sleep quality. In addition, performance in Visual Paired Associates test was negatively correlated with subjective sleep quality, duration, and sleep disturbances. Performance on the Word Learning test was negatively correlated with subjective sleep quality and efficiency. Participants' sex showed a weak effect on Visual Paired Associates performance and sleep latency.

CONCLUSIONS

Medical professionals working with elderly patients should take into consideration the effect of poor sleep quality on memory. Cognitive impairment in these patients may be a manifestation of a neuroendocrine imbalance due to a disrupted circadian rhythm. More research is needed to prove this hypothesis.

Antifungal and Anti-Inflammatory Potential of Bupleurum rigidum subsp. paniculatum (Brot.) H.Wolff Essential Oil

Fungal infections remain a major health concern with aromatic plants and their metabolites standing out as promising antifungal agents. The present study aims to assess, for the first time, the antifungal and anti-inflammatory potential of Bupleurum subsp. paniculatum (Brot.) H.Wolff essential oil from Portugal. The oil obtained by hydrodistillation and characterized by GC-MS, showed high amounts of monoterpene hydrocarbons, namely α-pinene (29.0–36.0%), β–pinene (26.1–30.7%) and limonene (10.5–13.5%). The antifungal potential was assessed, according to CLSI guidelines, against several clinical and collection strains. The essential oil showed a broad fungicidal effect being more potent against Cryptococcus neoformans and dermatophytes. Moreover, a significant germ tube inhibition was observed in Candida albicans as well as a disruption of mature biofilms, thus pointing out an effect of the oil against relevant virulent factors. Furthermore, fungal ultrastructural modifications were detected through transmission electron microscopy, highlighting the nefarious effect of the oil. Of relevance, the oil also evidenced anti-inflammatory activity through nitric oxide inhibition in macrophages activated with lipopolysaccharide. In addition, the essential oil’s bioactive concentrations did not present toxicity towards macrophages. Overall, the present study confirmed the bioactive potential of B. rigidum subsp. paniculatum essential oil, thus paving the way for the development of effective drugs presenting concomitantly antifungal and anti-inflammatory properties.

Loss of thermal refugia near equatorial range limits

This study examines the importance of thermal refugia along the majority of the geographical range of a key intertidal species (Patella vulgata Linnaeus, 1758) on the Atlantic coast of Europe. We asked whether differences between sun-exposed and shaded microhabitats were responsible for differences in physiological stress and ecological performance and examined the availability of refugia near equatorial range limits. Thermal differences between sun-exposed and shaded microhabitats are consistently associated with differences in physiological performance, and the frequency of occurrence of high temperatures is most probably limiting the maximum population densities supported at any given place. Topographical complexity provides thermal refugia throughout most of the distribution range, although towards the equatorial edges the magnitude of the amelioration provided by shaded microhabitats is largely reduced. Importantly, the limiting effects of temperature, rather than being related to latitude, seem to be tightly associated with microsite variability, which therefore is likely to have profound effects on the way local populations (and consequently species) respond to climatic changes.

The state of the fishery, conservation and management of the stalked barnacle Pollicipes pollicipes in Portugal

The stalked barnacle Pollicipes pollicipes is the most important intertidal economical resource in Portugal. The assessment of the state of the fishery, conservation and management of P. pollicipes in Portugal was made for the first time in three regions with different regulations regarding this fishery: two marine protected areas ("Reserva Natural das Berlengas", RNB; and "Parque Natural do Sudoeste Alentejano e Costa Vicentina", PNSACV); and the Center coast. Different approaches (independent observations, inquiries, logbooks) and sources of data (past and recent) were used. An overall negative tendency of the state of the fishery and conservation of this resource was observed in all regions, with the exception of the stable tendency detected in PNSACV when using the inquiries approach. A weak management was considered to be in practice at Center and at PNSACV, while an acceptable management was inferred for RNB. We recommend a change into a co-management system that should be tested in pilot regions as RNB and/or PNSACV.

Systemic drugs inducing non-immediate cutaneous adverse reactions and contact sensitizers evoke similar responses in THP-1 cells

Contact sensitizers induce phenotypic and functional changes in dendritic cells (DC) that enhance their antigen-presenting capacity and, ultimately, modulate the T cell response. To evaluate if there is a similar effect of drugs causing T-cell-mediated cutaneous adverse drug reactions (CADR), we studied the in vitro effect of drugs on THP-1 cells, a cell line widely used to evaluate the early molecular and cellular events triggered by contact sensitizers. The effect of allopurinol, oxypurinol, ampicillin, amoxicillin, carbamazepine and sodium valproate, at EC30 concentrations, was evaluated on p38 MAPK activation, by Western Blot, and on the expression of genes coding for DC maturation markers, pro-inflammatory cytokine/chemokines and hemeoxygenase 1 (HMOX1), by real-time RT-PCR. Results were compared with lipopolysaccharide (LPS), a DC maturation stimulus, and the strong contact sensitizer, 1-fluoro-2,4-dinitrobenzene (DNFB). All drugs studied significantly upregulated HMOX1 gene transcription and all, except the anticonvulsants, also upregulated IL8. Allopurinol and oxypurinol showed the most intense effect, in a magnitude similar to DNFB and superior to betalactams. Transcription of CD40, IL12B and CXCL10 genes by drugs was more irregular. Moreover, like DNFB, all drugs activated p38 MAPK, although significantly only for oxypurinol. Like contact sensitizers, drugs that cause non-immediate CADR activate THP-1 cells in vitro, using different signalling pathways and affecting gene transcription with an intensity that may reflect the frequency and severity of the CADR they cause. Direct activation of antigen-presenting DC by systemic drugs may be an important early step in the pathophysiology of non-immediate CADR.

Respiratory sensitizer hexamethylene diisocyanate inhibits SOD 1 and induces ERK-dependent detoxifying and maturation pathways in dendritic-like cells

Respiratory allergy to low-molecular-weight chemicals is a current concern in the context of occupational health, and a certified method to identify respiratory allergens is still under investigation. The aim of this work was to unveil some of the poorly understood initial molecular events and toxicity pathways underlying respiratory sensitization, which might be crucial to disclosing the key building blocks of new testing strategies and may contribute to the development of a valid in vitro method for the identification of respiratory allergens. Immortalized human dendritic cell (DC)-like THP-1 cells were exposed to the respiratory allergen hexamethylene diisocyanate (HDI) for 6h, and the activation of several signaling pathways was analyzed. Mitochondrial membrane potential (MMP) alterations, superoxide anion (O2(-)) production, and gene expression modulation in HDI-treated cells were also evaluated. According to our results, HDI induces O2(-) increase (P < 0.001) through enzymatic inhibition of cytoplasmic superoxide dismutase 1 (P < 0.05), which might reduce MMP, further leading to mitochondrial O2(-) production. Increased O2(-) levels promote ERK phosphorylation (approx sixfold compared to control; P < 0.001) and downstream transcriptional increase of several genes: HMOX1 (P < 0.05), involved in the protection of chemical reactive species; MDR1 (P < 0.01), responsible for the efflux of xenobiotics in the cell; and CD83 (P < 0.05), a DC maturation marker. These results raise new perspectives on the action of respiratory allergens in DCs and point out key molecular events that are crucial for the development of the so-called adverse outcome pathways, particularly regarding O2(-) increase through enzymatic inhibition, and important for ERK activation. Furthermore, our results highlight the role of ERK signaling, but not p38 MAPK, in the activation of vital mechanisms in cells exposed to a respiratory allergen, such as cell detoxification, migration, and maturation.

Aspergilose pulmonar invasiva

Aspergillosis, the most frequent of pulmonary mycosis, represents a group of varying pathogenesis diseases with the same etiological agent--Aspergillus. This fungus is a saprophyte of normal respiratory airways, but the disease occurs in immunocompromised hosts. There are several anatomo-clinical forms, but it is important to know that some could be fatal, being necessary an early diagnosis and therapy. The authors describe an Invasive Pulmonary Aspegillosis case, in a immunocompromised patient submitted to long term corticotherapy treatment. Was started with liposomal Amphotericin B, discontinued due to nephrotoxicity and substituted by Itraconazol, with clinical, laboratorial and radiologic favourable evolution, as it's proven by imagiological studies.

Florfenicol feed supplemented decrease the clinical effects of Mycoplasma hyopneumoniae experimental infection in swine in México

The therapeutic value of Florfenicol feed supplemented was evaluated in conventional pigs to eliminate consequences of chronic infection of Mycoplasma hyopneumoniae. The experimental animals were pigs with an average of 16 kg, after intratracheally inoculation with M. hyopneumoniae they were divided in two experimental groups: (a) the non-medicated; and (b) the feed supplemented group (20 g Florfenicol/ton of feed) during the ensuing 35 days. The average daily weight gain of the Florfenicol-treated pigs (0.33±0.14 kg/day) was significantly higher than that of the non-treated ones (0.21±0.10 kg/day). In medicated animals was still impaired relative to that of the uninfected ones control group (0.39±0.02 kg/day). The average percentage of pneumonic gross lesions extensions' of the pigs groups was: 13.99% for M. hyopneumoniae infected non-medicated group; 1.79% M. hyopneumoniae infected, Florfenicol-treated group and, 0.56% of the uninfected control group. M. hyopneumoniae; colonization was detected at these levels in 7 and 9 members of the respective infected groups. The extent of the pneumonic lesions and M. hyopneumoniae generally was greater in the non-medicated pigs. Therefore, oral administration of Florfenicol via feed ingestion seemed to be somewhat effective in ameliorating the clinical effects of M. hyopneumoniae infection of swine.

Pharmacodynamic trial of nimotuzumab in unresectable squamous cell carcinoma of the head and neck: a SENDO Foundation study

PURPOSE

To assess the pharmacodynamic effects of nimotuzumab, an anti-epidermal growth factor receptor (EGFR) monoclonal antibody with intermediate affinity for the receptor, in skin and tumor tissues from head and neck cancer patients.

EXPERIMENTAL DESIGN

Pharmacodynamic study in patients with advanced squamous cell carcinoma of the head and neck, unsuitable for chemoradiotherapy, enrolled in a single-center trial. Patients received 8 weekly infusions of nimotuzumab. The first nimotuzumab infusion was administered 1 week before starting radiation, whereas the remaining doses were administered concomitantly with irradiation. Paired biopsies were taken from skin and primary tumors, before (pretherapy) and 1 week (on single-agent therapy) after first infusion. Immunohistochemistry was conducted to assay the effects of nimotuzumab on total and phosphorylated EGFR, phosphorylated extracellular signal-regulated kinase 1/2 (p-ERK1/2), p-AKT, and proliferation (Ki-67).

RESULTS

Nimotuzumab was well tolerated and there was no evidence of skin rash. Objective response was achieved in 9 of 10 patients. The pharmacodynamic assays showed inhibition of p-EGFR in both skin and tumor (P = 0.042 in skin and P = 0.034 in tumor). No significant changes in p-ERK1/2, p-AKT, or Ki-67 were detected in skin. In addition, lymphocytic infiltrates, folliculitis, or perifolliculitis were not observed. In tumor samples, there was an upregulation of p-AKT (P = 0.043), a reduction in proliferation index (P = 0.012), and a nonsignificant trend toward a decrease of p-ERK1/2 (P = 0.091).

CONCLUSIONS

The pharmacodynamic data confirmed the ability of nimotuzumab to decrease EGFR phosphorylation. Downstream effects were observed in tumor cells but not in skin, a finding that may help to explain the lack of skin rash in patients treated with nimotuzumab.

Detection of nosocomial malnutrition is improved in Amazon region by a standard clinical nutrition education program

BACKGROUND

In Brazil hospital malnutrition is highly prevalent, physician awareness of malnutrition is low, and nutrition therapy is underprescribed. One alternative to approach this problem is to educate health care providers in clinical nutrition. The present study aims to evaluate the effect of an intensive education course given to health care professionals and students on the diagnosis ability concerning to hospital malnutrition.

MATERIALS AND METHODS

An intervention study, based on a clinical nutrition educational program, offered to medical and nursing students and professionals, was held in a hospital of the Amazon region. Participants were evaluated through improvement of diagnostic ability, according to agreement of malnutrition diagnosis using Subjective Global Assessment before and after the workshop, as compared to independent evaluations (Kappa Index, k). To evaluate the impact of the educational intervention on the hospital malnutrition diagnosis, medical records were reviewed for documentation of parameters associated with nutritional status of in-patients. The SPSS statistical software package was used for data analysis.

RESULTS

A total of 165 participants concluded the program. The majority (76.4%) were medical and nursing students. Malnutrition diagnosis improved after the course (before k = 0.5; after k = 0.64; p < 0.05). A reduction of false negatives from 50% to 33.3% was observed. During the course, concern of nutritional diagnosis was increased (chi2 = 17.57; p < 0.001) and even after the course, improvement on the height measurement was detected (chi2 = 12.87; p < 0.001).

CONCLUSIONS

Clinical nutrition education improved the ability of diagnosing malnutrition; however the primary impact was on medical and nursing students. To sustain diagnostic capacity a clinical nutrition program should be part of health professional curricula and be coupled with continuing education for health care providers.

Weight evolution in girls treated for idiopathic central precocious puberty with GnRH analogues

Data concerning the effects of GnRHa on weight gain are scarce.

OBJECTIVE

To assess the variation of the body mass index (BMI) in girls during GnRHa treatment for idiopathic central precocious puberty (CPP).

PATIENTS AND METHODS

Semestral anthropometric data from 176 girls treated with goserelin or leuprorelin were analyzed.

RESULTS

BMI z-score increased from 1.5 +/- 0.1 SD before treatment (n = 176) to 1.7 +/- 0.2 SD after 24 months (n = 61, p = 0.008). In girls with normal weight before treatment, this variation was greater (n = 112, 0.2 +/- 0.1 SD, p = 0.01) than in those who were overweight (n = 63, -0.9 +/- 0.2 SD, p = 0.7). In the goserelin group the weight change adjusted for bone age was greater (n = 28, 0.4 +/- 0.1 SD) than in the leuprorelin group (n = 5, 0.04 +/- 0.1 SD, p = 0.05).

CONCLUSIONS

A slight increase in BMI was noted, mainly in girls with normal weight before treatment. The influence of different GnRHa on weight must be further investigated.

A proposal for clinical nutrition education for health care university students and professionals in the Amazon

Changes in nutritional status are related to an increase in morbidity and mortality. It is well established that health care professionals, particularly physicians, lack formal education to recognize nutritional disorders, which malnutrition may worsen in the hospital, and that appropriate education could effectively correct this problem.

AIM

To evaluate the awareness of the health care university students and professionals about the nutrition disorders in Amazon region hospitalized patients before and after a specific education program.

STUDY DESIGN

An intensive Course on Clinical Nutrition, given in three weekly classes was offered to the multidisciplinary health care students and professionals of the health care tem.

CASES AND METHODS

195 participants started the course. They were 97 students of nursing, 52 students of medicine, 20 nurses, 15 resident physicians, 3 physicians, 3 dietitians, 2 others, 1 no answer. 165 participants concluded it. Precourse and postcourse tests were answered. The results of these tests are presented in this study.

RESULTS AND DISCUSSION

76.4% of the participants were graduation students. 40% of participants had no contact with patients yet. When the exposure of the participants of the course to the theme Nutrition was analyzed, 46.7% of the resident physicians considered

Quality of life of obese patients submitted to bariatric surgery

INTRODUCTION

The quality of life (QOL) of patients with morbid obesity (MO) is reduced given the restrictions it imposes. Bariatric surgery is considered an efficient treatment for MO as it leads to marked and progressive weight reduction. Weight loss, appropriate nutritional advice and follow up may induce significant improvement in QOL.

AIM

To evaluate the degree of QOL in patients with MO before and after bariatric, surgery (Fobi-Capella reducing gastroplasty). CASES.

MATERIAL AND METHODS

95 morbidly obese(BMI > 40 kg/m2) or moderately obese (BNI 35 - 39 kg/m2) patients with co-morbidities were seen, followed up and given advice by the Nutrition, Psychology, Endocrinology and Surgery staff at the Federal University of Bahia Hospital. Group I included 66 subjects at the pre-surgical stage and Group II was composed of 29 other patients in a late postsurgical phase. Group II patients were seen at 6, 12 and more months after bariatric surgery. The medical outcomes study Short-Form Health Survey (SF-36) was the instrument used to evaluate QOL in this study. Data were analyzed using the Mann-Whitney non-parametric method and the SPSS program.

RESULTS

A statistically significant improvement in QOL was detected in the aspects of general health, functional ability and vitality. A progressive improvement in physical conditioning was particularly observed in the patients who had had bariatric surgery less than 6 months before, between 6 and 12 months and more than 12 months before. Small changes in subjective features were seen. An improvement in social aspects was observed after a post surgical fall. This explains why do not changes appear when pre and post surgical patients are compared.

CONCLUSIONS

Fobi-Capella bariatric surgery for our patients with MO or with co-morbidities associated moderate obesity resulted in QOL improvement, and gradual but marked improvements in physical condition over time.

Intra-articular treatment of arthritis with microsphere formulations of paclitaxel: biocompatibility and efficacy determinations in rabbits

OBJECTIVES

To assess the biocompatibility of controlled release microspheres prepared from different polymeric biomaterials in various size ranges in rabbit synovial joints and based on these data, design and evaluate the efficacy of an intra-articular, paclitaxel-loaded microspheres formulation in rabbit models of arthritis.

METHODS

Paclitaxel-loaded microspheres of poly(lactide-co-glycolide) (PLGA), poly(L-lactic acid) (PLA) and poly(caprolactone) (PCL) were prepared in different size ranges and inflammatory responses monitored following injection into healthy rabbit joints. The efficacy of 20% paclitaxel-loaded PLA microspheres (35-105 microm size range) injected intra-articularly into antigen and carrageenan induced rabbit models of arthritis was monitored.

RESULTS

Polymeric microspheres in the 35-105 microm size range were biocompatible whereas smaller microspheres (1-20 microm) produced an inflammatory response. Efficacy studies showed that injection of 20% paclitaxel-loaded PLA microspheres significantly reduced all measures of inflammation in the antigen arthritis rabbit model.

CONCLUSIONS

Paclitaxel-loaded PLA microspheres in the 35-105 microm size range, released paclitaxel in a controlled manner over several weeks, and may be a potential formulation for the intra-articular treatment of inflammation in arthritic conditions.

Use of the humanized anti-epidermal growth factor receptor monoclonal antibody h-R3 in combination with radiotherapy in the treatment of locally advanced head and neck cancer patients

PURPOSE

To evaluate safety and preliminary efficacy of the humanized anti-epidermal growth factor receptor monoclonal antibody h-R3 in combination with radiotherapy (RT) in unresectable head and neck cancer patients. Secondary end points were the measurement of h-R3 serum levels and the assessment of the potential mechanisms of antitumor effect on patient biopsies. Anti-idiotypic response to h-R3 was assessed. To predict pharmacologic effect, a mathematical model for antibodies recognizing antigens expressed in tumors and normal tissues was built.

PATIENTS AND METHODS

Twenty-four patients with advanced carcinomas of the head and neck received six once-weekly infusions of h-R3 at four dose levels in combination with RT. Pretreatment tumor biopsies were obtained to evaluate epidermal growth factor receptor expression as an enrollment criterion. Second biopsies were taken to evaluate the proliferative activity and angiogenesis in comparison with the pretreatment samples. Patient serum samples were collected to measure h-R3 levels and anti-idiotypic response.

RESULTS

The combination of h-R3 and RT was well tolerated. Antibody-related adverse events consisted in infusion reactions. No skin or allergic toxicity appeared. Overall survival significantly increased after the use of the higher antibody doses. Immunohistochemistry studies of tumor specimens before and after treatment revealed that antitumor response correlated with antiproliferative and antiangiogenic effect. One patient developed antibodies to h-R3. The mathematical model predicted that the maximum difference between the area under the curve in tumors and normal tissues is reached when the antibody has intermediate affinity.

CONCLUSION

h-R3 is a well-tolerated drug that may enhance radiocurability of unresectable head and neck neoplasms.

Radioinmunolocalización de tumores de cabeza y cuello con un nuevo anticuerpo monoclonal contra el receptor del EGF. Resultados preliminares

OBJECTIVE

To show the results of Radioimmunodetection (RID) using Cuban monoclonal antibody (MoA) anti-egf-ior-egf-r3 labeled with 99mTc for the detection of primary tumors and/or metastases of head and neck epithelial malignant tumors.

MATERIAL AND METHODS

Thirteen patients aged from 16-62 years (mean: 54.8 years) with primary tumors and metastases in the regional cervical lymph nodes were retrospectively evaluated. The labelling dose was 1480-2220 MBq (40-60 mCi). Planar images were performed after 10 minutes and together with SPECT images after 18-24 hours following MoA administration. The matrix was 128 x 128. SPECT images were reconstructed using the Butterworth 4/16 filter. A positive result was defined when the lesions were visualized.

RESULTS

RID localized 11 of the known primary tumors in the 13 patients studied. In the two other patients, in whom the primary tumor site was unknown, cervical lymph node metastases were found. The results of 3 of the RID were false negative but in the other 10, RID was able to localize the primary tumor and cervical lymph node metastases. Sensitivity was 77 % and the predictive positive value was 100 %.

CONCLUSIONS

The results of this study show that the Cuban MoA ior-egf-r3 can be employed for RID of primary head and neck tumors and their metastases. The radiation dose is adequate for RID.

Nutritional assessment of adult patients admitted to a hospital of the Amazon region

Changes in nutritional status are important in clinical practice because they relate to an increase in morbidity and mortality. Studies about nutritional problems in hospitalized adults have been reported since the 1970s. The prevalence of malnutrition has varied from 10 to 70%, depending on the diagnostic criteria used. The hospital studied and the duration of admission.

AIM

To assess, in the first day of hospital stay, the nutritional status of adults admitted to undergo elective surgery in a public hospital of the State of Acre, Amazon Region, Brazil.

STUDY DESIGN

Sectional study from April 7 to May 22, 2002.

PATIENTS AND METHODS

155 consecutive nutritional evaluations were performed using several parameters-global subjective assessment (GSA), anthropometric measurement and some laboratory tests. For the diagnosis of malnutrition the Index Suggestive of Malnutrition (ISM), as proposed by Waitzberg, was adopted. In the evaluation of obesity the BMI (Body Mass Index), with cutoffs suggested by WHO was used.

RESULTS

75.2% were women. Average age was 34.4 +/- 10.1 years. Mulatto (63.1%) was the prevailing racial group. Gynecological (43.6%) was the most frequent surgery. ISM disclosed a 12.1% prevalence of malnutrition. BMI classified 2.0% of the patients as grade I overweight and 15.4% as being obese. Among 76 patients classified as normal by BMI, 15 (19.7%) were considered malnourished by ISM criteria. Concordance between ISM and BMI was weak (k = 0.07). GSA classified 100% of the cases as well nourished.

CONCLUSION

Lack of a golden standard to make the diagnosis of changes in nutritional status has been one of the determinants of the wide variations observed in the pertinent literature and it has hindered valid comparisons. The present study suggests that BMI should be used as an indicator of proportion and not of nutritional status. GSA underestimates the diagnosis of malnutrition. This paper concludes that establishing uniform standards for diagnostic criteria for malnutrition is urgently required and suggests preferring IMS (Index Suggestive of Malnutrition) because of its easy use, low coast and high sensitivity.

Free floating thrombus in right atrium and pulmonary thromboembolism

The authors describe a case of a patient with inoperable bladder cancer, who was admitted with syncope and arterial hypotension. After examination, an echocardiogram was requested, which showed a free-floating thrombus in the right atrium and dilatation of the right chambers. A diagnosis of pulmonary embolism was made, and heparin was started. The patient's clinical status worsened, with development of severe pulmonary hypertension due to the presence of large thrombi in the right and left pulmonary arteries. Despite a recent hemorrhagic event related to the bladder cancer, thrombolytic therapy was begun with improvement of the patient. The final echocardiogram was almost normal, without pulmonary hypertension and no dilatation of the right chambers.

[Invasive pulmonary aspergillosis]

Aspergillosis, the most frequent of pulmonary mycosis, represents a group of varying pathogenesis diseases with the same etiological agent--Aspergillus. This fungus is a saprophyte of normal respiratory airways, but the disease occurs in immunocompromised hosts. There are several anatomo-clinical forms, but it is important to know that some could be fatal, being necessary an early diagnosis and therapy. The authors describe an Invasive Pulmonary Aspegillosis case, in a immunocompromised patient submitted to long term corticotherapy treatment. Was started with liposomal Amphotericin B, discontinued due to nephrotoxicity and substituted by Itraconazol, with clinical, laboratorial and radiologic favourable evolution, as it's proven by imagiological studies.

Infection with human herpesvirus type 8 and human T-cell leukaemia virus type 1 among individuals participating in a case-control study in Havana City, Cuba

Infection with human herpesvirus type 8 and with human T-cell leukaemia virus type-1 shows strong geographic variations. We conducted this study to assess prevalence and risk factors for human herpesvirus type 8 infection in Havana City, Cuba. Information and residual serum samples already collected for a hospital based case-control study were used. A total of 379 individuals (267 males and 112 females; median age=63 years) were evaluated. Antibodies to the lytic antigen of human herpesvirus type 8 were detected by using an immunofluorescence assay, while human T-cell leukaemia virus type-1 serology was performed by means of an ELISA test (alpha Biotech). Overall, 64 subjects (16.9%, 95% confidence interval: 13.1-20.0) were positive for human herpesvirus type 8 antibodies. Human herpesvirus type 8 seroprevalence significantly increased with age (odds ratio=1.9 for >/=65 vs <55 years), and was twice as frequent in blacks than in whites. No association emerged with gender, socio-economic indicators, family size, history of sexually transmitted disease, sexual behaviour. Overall, 16 persons had anti-human T-cell leukaemia virus type-1 antibodies (4.2%, 95% confidence interval: 2.2-6.4). No relationship emerged between human T-cell leukaemia virus type-1 and human herpesvirus type 8 serostatus. The study findings indicate that human herpesvirus type 8 infection is relatively common in Havana City, Cuba, suggesting that Cuba may represent an intermediate endemical area. Sexual transmission does not seem to play a major role in the spread human herpesvirus type 8 infection.

Intestinal anti-inflammatory activity of morin on chronic experimental colitis in the rat

BACKGROUND

Morin, a bioflavonoid with antioxidant properties, shows intestinal anti-inflammatory activity in the acute phase of the trinitrobenzenesulphonic acid model of rat colitis.

AIM

To assess the anti-inflammatory activity of morin in the chronic stages of trinitrobenzenesulphonic acid-induced rat colitis.

METHODS

Rats were rendered colitic by a single colonic instillation of 30 mg of the hapten trinitrobenzenesulphonic acid dissolved in 0.25 mL of 50% ethanol. A group of colitic animals was given morin orally at doses of 25 mg/kg daily. Animals were sacrificed every week for 4 weeks. Colonic damage was evaluated macroscopically and microscopically. Different biochemical markers of colonic inflammation were also assayed, including myeloperoxidase activity, leukotriene B4 and interleukin-1beta synthesis, glutathione and malonyldialdehyde levels and nitric oxide synthase activity.

RESULTS

The administration of morin facilitated tissue recovery during the 4 weeks following colonic insult with trinitrobenzenesulphonic acid, as demonstrated macroscopically and microscopically, as well as biochemically by a reduction in myeloperoxidase activity. The intestinal anti-inflammatory effect of morin was accompanied by a significant reduction in colonic leukotriene B4 and interleukin-1beta levels, improvement in colonic oxidative stress and inhibition of colonic nitric oxide synthase activity.

CONCLUSIONS

Morin exerts a beneficial anti-inflammatory effect in the chronic phase of trinitrobenzenesulphonic acid-induced rat colitis through the down-regulation of some of the mediators involved in the intestinal inflammatory response, including free radicals, cytokines, leukotriene B4 and nitric oxide.

[Gangrenous cystitis]

Gangrenous cystitis is a rare condition, there are no typical symptoms or clinical findings, which hampers diagnosis and may worsen the prognosis. The authors report the case of a diabetic male patient, hospitalized because of poor general condition, dehydration and diffuse abdominal pain. The diagnosis was made by typical pelvic CT findings. Medical treatment must be intensive and begun as soon as possible. As in the present case, the situation may have a favorable outcome.

Effects of silymarin on the acute stage of the trinitrobenzenesulphonic acid model of rat colitis

The intestinal anti-inflammatory activity of several doses of silymarin was tested in the acute stage of the trinitrobenzenesulfonic acid (TNBS) model of rat colitis. The results obtained show that oral pre-treatment with 50 mg/kg of silymarin significantly attenuated macroscopic colonic damage as well as reduced colonic myeloperoxidase activity compared to non-treated colitic animals. The beneficial effect was accompanied by an improvement in the colonic oxidative status, which was altered in colonic inflammation, by preventing glutathione depletion and reducing malonyldialdehyde production. This suggests that the well known antioxidant properties of silymarin can participate in its intestinal anti-inflammatory activity. In addition, a preservation in the colonic absorptive function was also observed, and this effect can also account for the colonic protective effect observed in this model of acute colitis.

Thyroid disease in HCV carriers undergoing antiviral therapy with interferon plus ribavirin

High prevalence of thyroid autoantibodies, with or without overt thyroiditis, has been described in hepatitis C patients, particularly in those undergoing alpha-interferon treatment. The aim of this study was to describe the frequency and clinical outcome of thyroid disease in a cohort of HCV carriers before and during combination therapy with interferon plus ribavirin. Between May, 1997, and May, 1999, 111 previously untreated (naive) patients were treated with a-interferon plus ribavirin for 6 or 12 months. Of those, 67 (60%) patients were male and 44 (40%) female. Thyroid function was evaluated in all patients by testing free T4, TSH and antiTPO within 30 days prior to treatment, 90 days after treatment was initiated, and 6 months after treatment was concluded. Abnormal thyroid tests were observed in 4 (3.6%) patients--1 male and 3 female--before the onset of antiviral treatment. Three patients were already undergoing T4 replacement due to Hashimoto thyroiditis and 1 patient had positive antiTPO with normal free T4 and TSH. All 4 patients completed the treatment regime for HCV, but required hormone replacement. Among the patients with a normal thyroid function test prior to treatment (107 cases), 5 (4.6%) developed thyroid test abnormalities; 2 patients had hypothyroidism due to autoimmune thyroiditis; 1 patient became positive for antiTPO antibodies but thyroid function remained normal, and 2 patients had subacute thyroiditis. Four of these patients (80%) were female and 1 was male (20%). A family history of thyroid disease was strongly predictive of thyroid abnormalities during antiviral treatment. In conclusion, there is a low prevalence of thyroid function abnormalities in HCV carriers with no prior antiviral treatment. Family history of thyroid disease reinforces the special attention to thyroid abnormality development before considering antiviral therapy. Subacute thyroiditis during combination therapy was observed, but its pathogenesis is still unknown. Evaluation of thyroid function during and after antiviral treatment is strongly recommended because thyroid related symptoms can be easily misinterpreted as medication side effects.

Subacute thyroiditis during treatment with combination therapy (interferon plus ribavirin) for hepatitis C virus

Autoimmune thyroiditis has been frequently reported during interferon monotherapy for hepatitis C, but there are few reports concerning subacute thyroiditis. Recently, combination therapy of IFN plus ribavirin has become the preferred therapeutic schedule for chronic hepatitis C. Similarly to interferon monotherapy, there are no reports concerning subacute thyroiditis during combination therapy. We described four episodes of subacute thyroiditis occurring in three patients during antiviral combination therapy. All patients had symptoms compatible with hyperthyroidism, which could be misdiagnosed as IFN side-effects. The antiviral treatment was continued in all three patients and thyroid function increased progressively with pharmacological treatment for hyperthyroidism. We concluded that subacute thyroiditis may be a complication of combination antiviral therapy and should be investigated in patients presenting with compatible symptoms, in order to differentiate from IFN side-effects.

Inhibition of experimental allergic encephalomyelitis in the Lewis rat by paclitaxel

Experimental allergic encephalomyelitis (EAE), an animal model for multiple sclerosis (MS), is useful for preclinical testing for agents to be considered for treatment for this human demyelinating disease. Microtubules in lymphocytes play an important role in the cascade of human T cell activation, and paclitaxel (PTX), a microtubule stabilizer, can inhibit T cell function. A new formulation of micellar PTX, free of Cremophor and ethanol, was tested for its effect on the induction of EAE in Lewis rats. Adoptive EAE was induced with an encephalitogenic T cell line activated with guinea pig myelin basic protein (GP MBP) peptide 68-88. PTX (10 mg/kg) was administered 24 and 72 h after cell transfer. The clinical signs, fulminating in controls, were completely blocked by PTX, but mild CNS inflammation remained unaltered. A similar dose of PTX, given on days 6 and 8 to animals developing active EAE after immunization with GP MBP peptide 68-88 in complete Freund's adjuvant, greatly reduced the severity of paralysis and delayed the onset of disease by 8-9 days. Marked weight loss and severe toxicity were noted with higher and more prolonged administration. In vitro micellar PTX inhibited activation of encephalitogenic T cells by both specific antigen and mitogen. Lower doses and longer treatment programs may provide effective treatment with acceptable adverse effects with this agent in the treatment of inflammatory demyelinating disease.

Photosensitization of lymphoblastoid cells with phthalocyanines at different saturating incubation times

Photodynamic therapy of cancer is a promising treatment based on the tumor-specific accumulation of photosensitizers followed by irradiation with visible light which induces tumor cell death. The effect of different preincubation times on the photosensitization efficiency of the phthalocyanines AlPc and AlPcS4 was investigated in lymphoblastoid CCRF-CEM cells under conditions that allow maximal uptake of the sensitizers. First, the time course for the uptake of AlPcS4 and AlPc by CCRF-CEM cells and by the pheochromocytoma PC12 cells was compared. The uptake of AlPcS4 by CCRF-CEM cells was not significantly different after 6 h or 24 h incubation, but the photosensitization efficiency of the phthalocyanine was much higher when a 24 h preincubation period was used, with a fluence rate of 5 mW/cm2. However, for a fluence rate of 10 mW/cm2, the photosensitization efficiency of AlPcS4 was almost completely independent of the preincubation time (6 h vs. 24 h) with the phthalocyanine. When the cells were preincubated with 1 micromol/L AlPc for 10 min or 6 h, which allows the same accumulation of sensitizer by the cells, no significant effect of the incubation time on the photodynamic inactivation of CCRF-CEM cells was observed, with fluence rates of 5 mW/cm2 or 10 mW/cm2, for different light doses. Confocal fluorescence microscopy studies did not reveal differences in the localization of the phthalocyanines after maximal uptake was reached. The results show that the preincubation time with AlPcS4, after the maximal uptake is reached, affects cell growth to an extent depending on the fluence rate used, and this effect was not due to a major redistribution of the sensitizer during incubation. However, this was not observed when AlPc was used.

Anti-inflammatory activity of diosmin and hesperidin in rat colitis induced by TNBS

The intestinal anti-inflammatory activity of two flavonoids, hesperidin and diosmin, was evaluated in the acute stage of the trinitrobenzenesulfonic acid (TNBS) model of rat colitis. The results obtained showed that pretreatment with diosmin (10 mg/kg) or hesperidin (10 and 25 mg/kg) reduced colonic damage compared to TNBS control rats. This effect was confirmed biochemically by a reduction in colonic myeloperoxidase activity compared to non-treated colitic animals. Colonic glutathione levels in colitic animals were significantly increased after hesperidin or diosmin treatment. Diosmin decreased colonic MDA production and inhibited LTB4 synthesis, whereas hesperidin failed to do so. Conversely, only hesperidin improved colonic fluid absorption, which was impaired in colitic animals. In conclusion, both diosmin and hesperidin were able to prevent colonic inflammation, acting via a mechanism in which protection against oxidative insult may play a role.

Effects of morin on an experimental model of acute colitis in rats

The flavonoid morin was tested for anti-inflammatory activity in trinitrobenzenesulfonic acid (TNBS)-induced rat colitis. Rats were pretreated orally with several doses of the flavonoid (5, 10, 25, 100 and 200 mg/kg) 48, 24 and 1 h before and 24 h after colitis induction and examined for colonic damage 48 h after colitis induction. Colonic inflammation was characterized by diffuse hemorrhagic necrosis of the mucosa, bowel wall thickening, impairment of fluid absorption, increase in myeloperoxidase (MPO) activity, enhanced leukotriene B4 (LTB4) synthesis, glutathione depletion and increased levels of malonyldialdehyde (MDA). Morin treatment, at doses ranging from 10 to 200 mg/kg, significantly reduced colonic macroscopic damage. This beneficial effect was also confirmed by inhibition of colonic MPO activity. Several mechanisms may contribute to the protective effect exerted by morin. First, inhibition of colonic LTB4 synthesis is a common feature for all the active doses of the flavonoid. Second, the antioxidant properties of morin, which partially prevented colonic glutathione depletion (at doses of 10 and 25 mg/kg) or inhibited colonic MDA production (at doses of 100 and 200 mg/kg), can collaborate in preventing TNBS-induced inflammation.

The effect of magnesium supplementation in increasing doses on the control of type 2 diabetes

OBJECTIVE

Hypomagnesemia occurs in 25-38% of patients with type 2 diabetes. Several studies have suggested an association between magnesium (Mg) depletion and insulin resistance and/or reduction of insulin secretion in these cases. Our purpose was to evaluate if Mg supplementation (as magnesium oxide [MgO]) would improve metabolic control in patients with type 2 diabetes.

RESEARCH DESIGN AND METHODS

We studied 128 patients with type 2 diabetes (32 men, 96 women, aged 30-69 years), treated by diet or diet plus oral antidiabetic drugs, in the Bahia Federal University Hospital, Brazil. Patients at risk for hypomagnesemia or with reduced renal function were excluded. This study was a clinical randomized double-blind placebo-controlled trial. Patients received either placebo, 20.7 mmol MgO, or 41.4 mmol MgO daily (elementary Mg) for 30 days. Mg concentrations were measured in plasma, in mononuclear cells, and in 24-h urine samples. Fasting blood glucose, HbA1, and fructosamine were used as parameters of metabolic control.

RESULTS

Of the patients, 47.7% had low plasma Mg, and 31.1% had low intramononuclear Mg levels. Intracellular Mg in patients with diabetes was significantly lower than in the normal population (62 blood donors; 1.4 +/- 0.6 vs. 1.7 +/- 0.6 micrograms/mg of total proteins). No correlation was found between plasma and intracellular Mg concentrations (r = -0.179; P = 0.15) or between Mg concentrations and glycemic control (r = -0.165; P = 0.12). Intracellular Mg levels were lower in patients with peripheral neuropathy than in those without (1.2 +/- 0.5 vs. 1.5 +/- 0.6 micrograms/mg). Similar findings were observed in patients with coronary disease (1.0 +/- 0.5 vs. 1.5 +/- 0.6 micrograms/mg). In the placebo and in the 20.7 mmol Mg groups, neither a change in plasma and intracellular levels nor an improvement in glycemic control were observed. Replacement with 41.4 mmol Mg tended to increase plasma, cellular, and urine Mg and caused a significant fall (4.1 +/- 0.8 to 3.8 +/- 0.7 mmol/l) in fructosamine (normal, 1.87-2.87 mmol/l).

CONCLUSIONS

Mg depletion is common in poorly controlled patients with type 2 diabetes, especially in those with neuropathy or coronary disease. More prolonged use of Mg in doses that are higher than usual is needed to establish its routine or selective administration in patients with type 2 diabetes to improve control or prevent chronic complications.