Recent Trends in Brazilian Medical Research. An Overview

This article reviews 69 original research articles published in 6 Brazilian Medical Journals recently incorporated into the Institute for Scientific Information Journal of Citation Reports, with a view of making them comprehensively available to the readership of CLINICS within a subject category division. We expect this review to increase the visibility of a wide specter of original Brazilian research which may otherwise remain relatively unseen by the interested readership.


INTRODUCTION
Brazilian Medical Research is on the increase. However its visibility is still somewhat limited in spite of the enormous progress afforded by the institution of SciELO, the Electronic Scientific Library Online, which has gathered a collection of over 500 Latin American, Caribbean, and Iberian periodicals. The number of Brazilian Journals included in the Institute for Scientific Information Journal of Citation Reports has also increased significantly, but a number of newly included journals is still in the process of establishing a 3 year collection period which will enable them to have published impact factors. While this process is underway CLINICS has decided in conjunction with other Brazilian Medical Journals to make part of this collection of scientific reports available to its own readership. A systematic collection of original research articles from 6 of these Brazilian Journals is reviewed herein.
This review examines the papers appeared in Brazilian Medical Journals recently admitted to the Journal of Citation Reports database. The scope is to increase the visibility of such articles to the readership of CLINICS. Six Journals (Acta Ortopedica Brasileira, Arquivos Brasileiros de Cardiologia, Revista Brasileira de Cirurgia Cardíaca, Revista Brasileira de Medicina do Esporte, Revista da Associação Médica Brasileira, and São Paulo Medical Journal) were surveyed and papers published in the year 2007 were scanned for citations in the Journal of Citation Reports: Cited articles from each journal were selected and divided into subject categories.
A total 69 articles were selected and divided into 14 categories. In view of their multidisciplinary nature, some articles are included in more than one category. Categories and articles are as follows:

Cardiovascular
Under this general heading we detected the presence of articles on arterial disease, cardiac surgery, clinical cardiology and hypertension Arterial Disease. Makdisse et al. 1 evaluated a transcultural adaptation of a questionnaire on intermittent claudication, and conclude that the Brazilian Portuguese version of the Edinburgh claudication questionnaire maintained good sensitivity and specificity and can be recommended for screening of peripheral artery disease in clinical practice and epidemiological research in Brazil. Rocha et al. 2 describe the hemodynamic behavior of arterial anastomosis using fibrin sealant in a porcine model, and conclude that this may reduce the number of required stitches.
Cardiac Surgery. Cardoso et al. 3 found that the Amplatzer ™ device for transcatheter closure of an ostium secundum atrial septal is an effective new development. Takiuti et al. 4 evaluated the quality of life after myocardial revascularization and found improvement in all domains and in the three therapeutic modalities (clinical, stent placement and surgery). Comparatively, surgery however did provide a better quality of life after a four-year follow-up. Meireles et al. 5 compared the effectiveness of diamond-like carbon coated stainless steel stent versus uncoated stent implantation in patients with coronary artery disease, but conclude that no better outcomes resulted from the use of the coated stent. Miana et al. 6 discuss immediate results of right internal thoracic artery and radial artery as the second arterial graft in myocardial revascularization and find that the use of a Right Internal Thoracic Artery as a second arterial graft was associated with a prolonged operative time, but had no interference with the immediate clinical outcomes. Viaro et al. 7 , examined endothelial dysfunction caused by acute pressure distension of human Saphenous Vein used for myocardial revascularization and find that although vascular reactivity impairment was not demonstrated in vitro, the CD34 expression, measured by imunohistochemistry, shows there is endothelium dysfunction at pressures of 300 mmHg. Martins et al. 8 constructed coronary artery bypasses using both Internal Mammary Arteries in patients with diabetes mellitus and find that such patients can benefit of double grafting, with little increase in risk for complications if its application is carefully indicated. Nery et al. 9 described the influence of physical exercise in the outcome of myocardial revascularization and conclude that cardiac surgery promoted a modification of the habits of the patients increasing the number of physically active patients during a one year follow up. Avila Neto et al. 10 surveyed the effect of temporary right atrial pacing in prevention of atrial fibrillation after coronary artery bypass graft surgery. They also find a reduced the incidence of atrial fibrillation after the surgery. Older age and non-atrial pacing were the independent predictive factors of the occurrence of this arrhythmia. Beani et al. 11 discuss the use of late pulmonary tomography assessment in management of ductus arteriosum in premature infants with bronchopulmonary dysplasia, but find that the procedure is without influence on outcome. Silva et al. 12 describe an experimental study on the use of a bicaval cannula for the approach of the pulmonary valve. Dinkhuysen et al. 13 reports on the conception and development of a new spiral blood pump General Clinical Cardiology. Souza et al. 14 evaluated cardiac tissue adaptations in rats submitted to aerobic training after nitric oxide (NO) synthesis blockade and found that short term NO synthesis blockade in sedentary animals induced hypertension but did not cause cardiac hypertrophy. In the trained animals, the inhibition of NO synthesis attenuated hypertension, induced cardiac hypertrophy and significantly increased myocardial fibrosis, indicating that NO plays an important role in cardiac tissue adaptations caused by aerobic exercise. Ferreira et al. 15 found that thermal dilution and trans-esophagic echodoppler yield comparative and reproducible measurements of cardiac output. Menezes Junior et al. 16 showed that the combined effect of optimized atrial stimulation and atenolol is more effective in controlling recurrent atrial fibrillation. Esporcatte et al. 17 showed that myeloperoxidase is highly effective in predicting high risk in patients with acute chest pain; Guerzoni et al. 18 found that the TT genotype of the methyl-N-tetrahydrofolate reductase gene associates with more serious cases of coronary obstruction. while Villacorta et al. 19 claim that C-reactive protein is an inflammatory marker with prognostic value in patients with decompensated heart failure. Nascimento et al. 20 find that the midazolan was associated with a greater sedative and cardiovascular effect than diazepam in patients undergoing hemodynamic studies for suspected coronary artery disease. Issa et al. 21 found that bisoprolol was found to be safe and well tolerated in patients with heart failure, improved symptoms, hemodynamic variables, as well as the cardiac function for all etiologies of heart failure, but did not result in improved exercise capacity. Azevedo et al. 22 described cardiac and metabolic characteristics of long distance runners.
Hypertension. Costa et al. 23 , Jardim et al. 24 and Souza et al. 25 evaluated prevalence of hypertension and its associated risk factors in adults: a population-based study in the major Brazilian cities, while Freitas et al. 26 performed a combined analysis of genetic and environmental factors on essential hypertension in a Brazilian rural population in the Amazon region. Rosa et al. 27 examined body mass index and waist circumference as markers of arterial hypertension in adolescents and found to be poorly sensitive markers. Silva et al. 28 in contrast find that body overweight acted out as the only potential risk factor increasing arterial blood pressure in adolescents, irrespective of their sex and age. Cavalcante et al. 29 quality of life of hypertensive patients treated at an outpatient clinic is not negatively affected because of the asymptomatic nature of the disease.

Epidemiology and Public Health
Apart from the previously described studies 25,26 five other significant epidemiological studies were published. Glasberg et al. 30 report that burnout is prevalent among Brazilian oncologists, but that oncologists having sufficient personal and social resources to engage in a hobby, physical activity, have enough vacation time and religious activities are at lower risk of developing burnout, Gawryszeski, et al. 31 examined the prevalence of injury mortality and describe data which indicate a need to develop injury prevention strategies, considering the magnitude of the problem and the groups at high risk. Homicides among young people have to be addressed, while motor vehicle traffic injuries play an important role for all ages. Ângelo et al. 32 determined echocardiographic reference values for cardiac chambers, left ventricular mass, and left ventricular mass indexes in an asymptomatic adult population sample and expect that results will be useful as a reference, since they are consistent with the new limits suggested in the literature for the echocardiographic diagnosis of left ventricular hypertrophy.

Gastroenterology
Bachella et al. 33 compared the outcomes from marginal and non-marginal graft transplantation in 103 cases of liver transplantation due to chronic hepatic failure and found that marginal grafts increase early mortality in liver transplantation.

Gynecology
Ribeiro et al. 34 report data that suggest that hysteroscopy is valuable as a diagnostic tool for malignant/hyperplastic and benign lesions, except for submucous myomas, for which the sensitivity was only 52.6%.

Immunology
A study by Soares et al. 35 on domestic allergens showed that the highest sensitization in allergic patients under study was to dust mites, especially Dermatophagoides pteronyssinus and Dermatophagoides farinae. They also note that the number of patients sensitized to cockroach extract was uncommonly high when compared to previous studies.

Nephrology
Taniguchi et al. 36 reported that cardiopulmonary bypass time is a risk for renal failure, the greatest likelihood of developing kidney failure after heart surgery is observed when cardiopulmonary bypass time is at least 90 minutes, although creatinine clearance or mortality were not significantly different compared to lower duration procedures.

Neurology
Hirakawa et al. 37 compared the effects of fibroblast growth factor and nerve fragments on tibial nerve regeneration in rats and found a higher amount of neurons on the side where the growth factor was used compared to the side where nervous fragments were placed, suggesting a superior performance of the fibroblast growth factor over nerve fragments for stimulating nervous regeneration. Braga Silva et al. 38 described a new experimental model of spinal cord injury in rats with a device for local therapeutic agents access for the study of different modifiers of the regenerative response. Saba et al. 39 describe the total absence of neuroprotective effects of diltiazem in rabbits with occluded aorta. Neuroprotective effects of diltiazen, Benício et al. 40 compared ischemic preconditioning and cerebrospinal fluid drainage as methods of spinal cord protection in dogs and found that cerebrospinal fluid drainage and immediate ischemic preconditioning seem to protect the spinal cord during descending thoracic aorta cross-clamping. Nevertheless, spinal cord protection seems to be more significant with cerebrospinal fluid drainage.

Nutrition
A general and new development emerging from Brazilian nutritional research is the fact that obesity is gradually replacing malnutrition as the chief problem throughout the country. Barbosa et al. 41 showed an association between nutritional status and functional capacity for elderly women in the city of São Paulo. Obesity was the nutritional condition associated with the worst performance in the tests. Nunes et al. 42 find that overweight, obesity, excessive TV watching time, unhealthy feeding habits were observed across classes in the Northeastern Brazilian city of Campina Grande. Velásquez-Meléndez et al. 43 found metabolic syndrome was also found to be prevalent in a rural community in the state of Minas Gerais. Karnikowski et al. 44 describe non-alcoholic fatty liver disease and metabolic syndrome in a population of middle aged and older adults in Brasilia. Santos et al. 45 examined the nutritional status, iron, copper, and zinc levels in school children of shantytowns of Sao Paulo and found to have low stature, with lower levels of malnutrition than of obesity, and anemia, which however was not associated to iron, copper or zinc deficits, As described above, body mass index and waist circumference were not found to be good markers of arterial hypertension in adolescents. 27 In rats fed with a cholesterol rich diet, Paulo et al. 46 found that total splenectomy caused a significant increase of cholesterol, LDL, VLDL and triglycerides.

Oncology
Trufelli et al. 47 evaluated the prognostic value of the ratio between positive and total dissected lymph nodes in patients with colon cancer who underwent primary tumor surgical resection and conclude that in the limited retrospective series studied, the ratio between positive and dissected Recent trends in Brazilian Medical Research. An overview Rocha-e-Silva M lymph nodes was not independently associated with overall survival among patients. Battaglini et al. 48 examined the effects of an individualized exercise intervention on body composition in breast cancer patients undergoing treatment and conclude that the results suggest that exercise emphasizing resistance training promotes positive changes in body composition and strength in breast cancer patients undergoing treatment., Saad et al. 49 surveyed predictors of quality-of-life improvement following pulmonary resection due to lung cancer and found that the predictors that positively affected quality of life were better forced vital capacity, and six-minute walking test, as well as less extensive lung resection. Three months after the surgery, an improvement in social life was already seen.

Orthopedics
Nunes et al. 50 studied genetic and environmental factors involved on intervertebral disc degeneration and found a correlations between Fokl polymorphism, early degeneration, and intervertebral disc degeneration severity. Smoking habits were also found to interfere in this process, regardless of the presence or absence of a favorable genotype for glutathione transferase M1 and T1 genes. Oliveira et al. 51 studied normal and degenerated intervertebral discs' mechanoreceptors of human lumbar spine through X-ray, magnetic resonance and pathoanatomy, finding (a) type-III fibers to be more common at the anterior region; (b) type-II and type-IV fibers more common at the posterior region, and (c) type-I fibers not to show any differences regarding anterior and posterior regions; in addition, degenerated discs have more nervous fibers than normal ones. , Rocha et al. 52 reviewed 71 patients diagnosed with anterior cruciate ligament injury on 72 knees. The incidence of associated injuries (meniscal and joint cartilage injuries) were evaluated according to the time elapsed until ligament reconstruction. They observed a non-significant trend towards a higher number of meniscal injuries after 6 months, and of joint-cartilage injuries after 12 months since the primary anterior cruciate ligament injury. Rebelatto et al. 53 studied general characteristics, determinant factors and relationship with handgrip strength of falls in institutionalized elderly people in the large provincial city of São Carlos, and found the incidence of falls and the individuals who were more likely to suffer falls were the older and weaker ones, as well as those unable to watch television. Franco et al. 54 performed an experimental study in fresh human cadavers to determine the resistance of osteosynthesis with plates and screws in anterior cervical spine fixation: three different types of plates (H-type Orozco's plate, conventional 1/3 tubular plate, plate described by Mendonça) were applied to segments of the cervical spine (C3-C7), and concludes that fixation with the H plate offers better stability when compared to other fixations and that the plates and screws used in the study decreased resistance when compared to an untreated control group. Fernandes et al. 55 compared back pain in patients with breast hypertrophy vs. normal sized breast and showed that back pain is more severe and determined more extensive limitations in the daily activities for patients presenting breast hypertrophy. Kirkwood et al. 56 performed a biomechanical analysis of hip and knee joints during gait in elderly subjects, examining the range of motion, force momentum, power and the mechanical work performed by hip and knee joints in a group of subjects aged between 55 and 75 years, and conclude that biomechanical analysis of the joints during different activities would help clinicians to identify and understand important variables required for improving the performance and deficits of elderly individuals. Lustosa et al. 57 compared muscular and functional performances, and passive joint laxity between volunteers who, after ligament reconstruction, returned to the same pre-injury activity level and those who did not. They found no differences between legs (operated and not operated) and conclude that passive joint laxity or muscular and functional performances cannot explain the return of the individuals to their same pre-injury functional level. Pizzato et al. 58 analyzed of the medium frequency of the electromyographic signal of individuals with lesion of the anterior cruciate ligament in isometric exercises of open and closed kinetic chain. They found smaller medium frequency values in anterior cruciate ligament deficient subjects when compared with counter lateral and control groups in open kinetic exercises but no significant difference in closed kinetics exercises, and conclude that medium frequency can be considered an efficient tool in the anterior cruciate ligament injury characterization. Santos et al. 59 compared integrated electromyographic ratio of the Vastus Medialis Obliquus and Vastus Lateralis Longus muscles in gait in subjects with and without patellofemoral pain syndrome and found that that the ratio of the electric activity of the Vastus Medialis and Vastus Lateralis muscles in individuals with and without patellofemoral pain syndrome is equal in the gait on flat surface as well as on a 5 degree-slanted surface. Vital et al. 60 examined the incidence of orthopedic trauma in parolympic athletes, and conclude that the increased intensity of training for such national and international events has led to an increase of this incidence. They also stress the importance of reinforcing the preventive measures to the athletes.

Physical Exercise
Apart from the papers describing the interactions of physical exercise with orthopedic pathologies described above, [58][59][60] we highlight four other contributions. Sabbag et al. 61 studied the effects of physical conditioning over patients with fibromyalgia, and found that work capacity improved from the third month pain threshold increased from the sixth month, post-exertion pain and number of tender points decreased in the ninth month, and pain intensity decreased in the twelfth month. Gama et al. 62 studied the influence of the stretching frequency using proprioceptive neuromuscular facilitation in the flexibility of the hamstring muscles, and found that the stretching groups had a statistically significant range of motion gain in relation to the control group, Diefenthaeler et al. 63 compared absolute and relative physiological responses of cyclists and triathletes by measuring ventilatory threshold (an indicator of the lactate threshold) and maximal oxygen uptake during a bicycle ergometer test between cyclists and triathletes and found that the two groups showed different aerobic capacity because they have unlike physiological adaptations. Bertolla et al. 64 evaluated the effects of a training program using the Pilates method upon the flexibility of sub-20 years indoor soccer athletes, finding acute effects, represented by a statistically significant immediate increase of flexibility and a chronic effect, with a non-significant trend to decline in the long run.

Pneumology
Romanini et al. 65 analyzed the effects of intermittent positive pressure and incentive spirometry in the postoperative of myocardial revascularization, and found that the group submitted to incentive spirometry showed a significant increase in the maximum expiratory pressure 24 and 48 hours after surgery. They conclude that aiming at reversing hypoxemia earlier intermittent positive pressure was more efficient than inceptive spirometry, which however was more effective in improving respiratory muscle strength. Botter et al. 66 described the surgical treatment of giant emphysematous lung bullae, and conclude that of the several surgical modalities were performed to treat the emphysematous lung bullae, drainage of the bullae with local anesthesia and sprayed talc should be the preferred modality. Krause et al. 67 studied the influence of the level of physical activity over the cardiorespiratory capacity in older women, and found that, higher physical activity, especially higher sports physical activity, may attenuate the decrease of cardiorespiratory capacity in older women, suggesting that an increase of physical activities is recommended, especially regular physical exercises. Navarro et al. 68 examined the effectiveness and safety of endotracheal tube cuffs filled with air versus filled with alkalinized lidocaine: a randomized clinical trial, and found that lidocaine filled cuffs prevented the occurrence of high cuff pressures during N 2 O anesthesia, reduced endotracheal discomfort and postoperative sore throat incidence.

Sepsis
Cicarelli et al. 69 performed a prospective randomized clinical trial on the effects of early dexamethasone treatment for septic shock patients, and showed that it reduced the seven-day mortality with a trend towards reduction of 28day mortality.