Evaluation of RNA purification methods by using different blood stabilization tubes: identification of key features for epidemiological studies.

OBJECTIVE: Peripheral blood is the most promising source of RNA biomarkers for diagnostic and epidemiological studies, because the presence of disease and prognostic information is reflected in the gene expression pattern. Quality RNA is used by a number of different downstream applications, so the selection of the most appropriate RNA stabilization and purification method is important. We have analyzed the RNA purified from 300 blood samples from 25 donors processed by two technicians using three methodologies with Tempus and PaxGene tubes. RESULTS: The best quality sample results were obtained with the Tempus Spin RNA Isolation Kit and the PaxGene Blood miRNA Kit, although larger amounts of RNA were obtained with the Tempus Spin RNA Isolation Kit. Lower Cq values were observed for RNA and miRNA genes in samples that were tested with PaxGene Blood miRNA Kit and Tempus Spin RNA Isolation Kit respectively. We identify the Tempus Spin RNA Isolation Kit as the most robust methodology, whilst the MagMax for Stabilized Blood Tubes RNA Isolation Kit showed the most instability. For biobanks, which process a large cohort and conduct epidemiological studies, the Tempus Spin RNA Isolation Kit is the most appropriate methodology. The study demonstrates the robustness of real-life procedures.

Angioplastia con stents liberadores de rapamicina en diabéticos tipo 2: Experiencia del Hospital DIPRECA / Angioplasty stenting with Sirolimus (Rapamycin) eluting stents in type 2 diabetic patients

Background: Drug-eluting stents have been developed to reduce the rates of restenosis after coronary angioplasty. Several studies have demonstrated that rapamycin eluting stents are reliable and effective. Aim: To report the experience in our Health Centre with rapamycin-eluting stents. Patients and methods: Forty two stents with rapamicine were implanted to 32 diabetic patients, between June 2002 and December 2004. After the procedure, subjects were clinically followed-up for an average period of 19.9+9.9 months, evaluating functional capacity, angina pectoris, dyspnea, need for hospital admission, acute coronary events and cardiac death. In those subjects clinically suspected to have restenosis, a coronary angiography was performed. Results: Twenty-nine subjects (90.6 percent) remained asymptomatic, two subjects (6.3 percent) developed angina pectoris but restenosis was ruled out, and one subject (3.1 percent) died. Conclusions: The use of rapamycin-eluting stents in these patients was safe and successful with no evidence of clinic restenosis. These positive results are similar to those reported in the Diabetes Study.

Estudio comparativo, clínico radiográfico del sulfato férrico (15.5%) y formocresol (Fórmula de Buckley) en pulpotomías de molares deciduas: resultados a 12 meses / Comparative, clinical and radiographic of ferric sulfate (15.5%) and formocresol (Buckley's formula) in pulpotomy of deciduous molars: results at 12 months

El prop¢sito del presente estudio fue comparar la respuesta cl¡nica y radiogr fica del Formocresol (FMC) (F¢rmula de Buckley 1:5) y el Sulfato F‚rrico (SF) al 15.5% en el tratamiento de pulpotom¡as de dientes deciduos. Diecisiete molares deciduas de catorce ni¤os pertenecientes al C.E. 3023 Pedro Paulet Mostajo de Lima, Per£; fueron tratadas con la t‚cnica convencional de pulpotom¡as. A nueve de ellas se les aplic¢ FMC al 20% por cinco (5) minutos FMC y a ocho, SF al 15.5% por 20 segundo. Se utiliz¢ el cemento de Oxido de Zinc – Eugenol como cemento de base, el cemento de Fosfato de Zinc como cemento de subbase y el comp¢mero Compoglass como material de restauraci¢n final. Al control cl¡nico radiogr fico a los treinta d¡as se obtuvo un ‚xito combinado de 100% (100% SF, 100%FMC). Al control a los noventa d¡as se obtuvo un ‚xito combinado de 76.5% (87.5%SF y 66.6% FMC) La alteraci¢n m s frecuente fue la reabsorci¢n interna de la ra¡z (17.6% de casos: 1/8 SF y 2/9 FMC).

The aim of this study was to compare the clinic and radiographic response of 20% Formocresol (FMC) (Buckley;s solution 1:5) and 15.5% Ferric Sulfate (FS) in pulpotomies performed in primary teeth. Seventeen primary molars of fourteen children from the 3023 “Pedro Paulet Mostajo” school at Lima-Peru, were treated with the pulpotomy conventional technique. Nine of them received FMC for five minutes, and eight of them, FS for 20 seconds. It was used Zinc Oxide-Eugenol cement as a base, Zinc Phosphate cement as a sub base and the Compoglass compomer as material of final restoration.

Gallbladder motility and lithogenesis in obese patients during diet-induced weight loss.

UNLABELLED: Obesity and weight loss are important risk factors for gallstone development. The mechanisms involved are unknown. We prospectively studied changes in gallbladder (GB) emptying and bile composition during weight loss. We studied 12 alithiasic obese subjects who entered a six-month diet program (800-1200 kcal/day, 26 g fat/day). As controls we evaluated 12 healthy nulliparous nonobese young women. GB volumes were studied by ultrasonography (fasting volume, GBFV; residual volume after a liquid meal, GBRV) at entry and after 4 and 20 weeks of dieting. Bile acid pool size, biliary lipid composition, presence of cholesterol crystals, and nucleation time were also studied. Of 12 obese subjects studied (mean BMI 35.1 kg/m2), 10 remained in the program for six months, but only six completed the entire study protocol, obtaining a significant weight loss (BMI: 31.2 kg/m2, P < 0.001). GBFV was greater in obese subjects than in nonobese controls (27.5 +/- 10.7 vs 11.7 +/- 6 ml; P < 0.05). GBRV and GB emptying curves were similar in both groups and did not change during weight loss. The obese subject who developed gallstones (1/10) was the only one who had cholesterol crystals in bile and a sluggish initial GB emptying. IN CONCLUSION: (1) obese subjects had a greater GBFV than controls; however, the GB emptying was adequate. (2) During weight loss we did not observe significant changes in GB kinetics or the bile parameters studied. (3) We observed a relatively low frequency of gallstone formation, which can be explained by a high fat content of the diet (26 g/day) and by the adequate GB emptying of our group of patients. (4) An abnormal GB contractility and cholesterol crystals in bile could be considered premonitory to gallstone formation.

[Health reform in Chile and the role of medical schools: an attempt of synthesis]. / La reforma de salud en Chile y el rol de las Facultades de Medicina: un intento de síntesis.

During the last ten years different institutions from the medical, educational, political and administrative settings have performed studies and made recommendations towards a health reform in Chile. In spite of frequent and sometimes strong ideological differences, most of these studies share the diagnosis of the main deficiencies and shortcomings of our public and private health systems. Furthermore, many of their recommendations are converging towards broad solutions-based on technical reasons--for the insurance systems and for the primary, secondary and tertiary care levels. This article tries to identify these convergences and describes the vital role of the Medical Schools in their eventual implementation (Rev Méd Chile 2000; 128: 1161-66).

[Evidence-based medicine]. / La medicina basada en evidencias.

The need to improve the quality of health care and to contain its costs has become mandatory. Simultaneously we are confronted by a growing body of clinical information, most of it irrelevant. This paper describes the origin and methods of Evidence-Based Medicine, a new alternative to the usual ways of medical information. The recent development of computerized data bases is permitting the rapid location of relevant clinical information concerning specific questions on diagnosis, therapy or prognosis. Critical analysis is then used to determine the validity of the evidence obtained, which can be employed in clinical decision making. The future role of Evidence-Based Medicine in education and clinical practice seems highly promissory.

[Study of volume and kinetics of gallbladder emptying in non-pregnant, pregnant, and puerperal women]. / Estudio del volumen y de la cinética del vaciamiento vesicular en mujeres nuligestas, en embarazadas y puérperas.

Gallbladder stasis apparently plays an important role in the patho-genesis of cholelithiasis during pregnancy. On the other hand, gallstones diagnosed immediately after delivery disappear spontaneously during late puerperium in one third of these patients. Gallbladder emptying was assessed by biliary scintigraphy and ultrasonography in normal, nulliparous volunteers. The two methods had an excellent correlation: thence, we used ultrasonography to determine gallbladder volume and contraction in pregnant and puerperal women. Fasting and postprandial residual volumes were significantly larger during pregnancy, while the kinetics f gallbladder emptying was similar in nulliparous and pregnant women. During puerperium, gallbladder volume returned to the values observed in nulliparae; but the kinetics of emptying was significantly faster, suggesting an increased sensitivity of gallbladder muscle to physiologic stimuli.

[The internist, today]. / El internista, hoy.

The crisis of Internal Medicine is universal, and its fragmentation in an increasing number of sub-specialties is still taking place, with the undesirable results of dehumanization, excessive technification and increasing costs. Recent data indicate the growing and worrisome shortage of general internists in our country. The Medical disadvantages of the predominant care by sub-specialists are analized. The main features of the modern general internist are described. Changes in medical education and health policies to increase their number and professional quality are suggested.

[Ideas contributing to the reform of the health sector in Chile]. / Algunas ideas para contribuir a la reforma del sector salud en Chile.

General criteria are proposed for the organization of chilean health system. The fundamental ideas emphasize administrative decentralization, an effective and expedite intercommunication between different attention levels and a rationalization of the use of diagnostic procedures and treatments. The "basic health plan" features are outlined. The need for patient and family education and the access to tertiary medicine only through referrals is highlighted. The second part of article proposes changes in Medical Education. The need to reorient undergraduate medical formation towards solving outpatient problems and to extend specialization possibilities to all graduates, including Adult and Children general medicine training programs, is emphasized. The incorporation of basic economical concepts to the curriculum and group work training is considered beneficial. Finally, self-teaching behaviors and resolutive capacities in legal and ethical aspects should be encouraged in students. The potential teaching roles of future health reference, diagnostic and therapeutic centers is insinuated.

Metaplasia and precursor lesions of gallbladder carcinoma. Frequency, distribution, and probability of detection in routine histologic samples.

BACKGROUND: Gallbladder diseases, especially cholelithiasis, are extremely frequent in Chile, and an increasing frequency of gallbladder carcinoma has been observed during the last decades. Hyperplastic and atypical epithelial lesions of gallbladder epithelium have been considered potential precursors of invasive carcinoma. The current study was designed to study the frequency, distribution, extension, and probability of routine detection of potentially preneoplastic changes of gallbladder epithelium. METHODS: Epithelial changes were histologically studied by mapping gallbladders obtained at elective cholecystectomy for lithiasis in 162 Chilean patients. RESULTS: Antral-type metaplasia was found in 95.1% of the cases, intestinal metaplasia in 58.1%, hyperplasia in 46.9%, dysplasia in 16%, and carcinoma in situ in 2.5%. A significant association of intestinal metaplasia with hyperplasia, intestinal metaplasia with dysplasia, and hyperplasia with dysplasia was found. Hyperplasia and dysplasia were also present in four cases with carcinoma in situ. Mean extension of the lesions (percentages of the sections in which the change was observed) was antral-type metaplasia (62.7%), intestinal metaplasia (25.3%), hyperplasia (24.1%), dysplasia (15.5%), and carcinoma in situ (9.7%). Antral-type and intestinal metaplasia were more extensive and more severe in patients older than 50 years of age. Hyperplasia was more extensive in cases in which it was associated with dysplasia and carcinoma in situ. CONCLUSIONS: The extension of metaplasia seems to depend in part on the age of the patients. The association of intestinal metaplasia with hyperplasia and dysplasia agrees with the findings of other authors that relate metaplasia to gallbladder cancer. The epithelial lesions are focal or partially confluent, thus a single random histologic section will detect less than one third of the hyperplasias, dysplasias, and carcinomas in situ.

Pregnancy and cholelithiasis: pathogenesis and natural course of gallstones diagnosed in early puerperium.

Several recent reports have indicated an increased prevalence of gallstones in association with pregnancy. If these reports are true, the early puerperium should be a favorable time to detect the disease in its initial stages and follow its natural course. Accordingly, the gallbladder was examined by ultrasound in 980 women during the immediate postpartum period and in 150 nulliparous, age-matched healthy volunteers. Gallstones were detected in 12.2% of the puerperal women and in 1.3% of the control group. In 70 patients who had stones in a functioning gallbladder, 22 (31%) had had attacks of biliary colic. The history of pain was more common in patients with stones greater than 10 mm in diameter. Forty-one women with small stones (< 10 mm) were followed clinically and ultrasonographically for between 6 and 24 (mean = 8.7) mo. All remained pain-free, and in twelve subjects (29%) the stones disappeared. Gallbladder bile was examined in 11 normal volunteers (controls) immediately after delivery and in 19 women with small stones 39 +/- 6 days postpartum. Bile was saturated with cholesterol in the controls and was unsaturated in patients with gallstones. We conclude that in our population pregnancy is a very important pathogenetic factor favoring gallstone formation. Attacks of biliary colic appear early and frequently in young Chilean women with this disease. Unexplained disappearance of small stones frequently occurs: in some cases it is likely to be the result of spontaneous dissolution because bile becomes unsaturated within a few weeks of delivery.

[Correlation between ultrasound and pathology of the gallbladder]. / Correlacion entre la ecotomografia y la anatomia patologica de la vesicula biliar.

Ultrasound is a sensible and specific method for the diagnosis, study of natural course and follow up of medical treatment of gallstones. Thus it is important to specify the concordance between echographic and pathological findings of the gallbladder. Ninety one patients were subjected to an ultrasound gallbladder examination immediately before elective surgery and the excised organ was pathologically examined right after the operation. The number and size of stones, the diameters and wall thickness of the gallbladder and the presence of polyps and septa were compared with both methods. The correlation was fair for the number or size of the stones considered separately; however the correct diagnosis of both parameters was obtained in only a third of the cases. Diameters of the gallbladder were underestimated by ultrasound; wall thickness measurement showed a very good correlation with both methods. No correlation was found for polyps or septa. Although ultrasound is excellent for the diagnosis of gallstones, its precision, is insufficient to determine the exact number and size of the stones.

[Miliary tuberculosis as a complication of BCG immunotherapy in cancer of the bladder. Case report]. / Tuberculosis miliar como complicacion de inmunoterapia con BCG en el cancer de vejiga. Caso clinico.

Intravesical administration of BCG may be used as an ancillary immunotherapy after endoscopic resection for cancer of the bladder. Local side effects are usually mild. Here is reported a patient who developed miliary tuberculosis after this form of therapy. Radiologic studies of the thorax and liver biopsy confirmed the diagnosis. The patient recovered after treatment with anti-tuberculosis drugs (TA-81 scheme). Epithelial trauma may be invoked as an alteration facilitating this complication. Although it develops infrequently, patients with bladder cancer treated with BCG must be monitored for this complication.

[Relations of the physician and his patients in today's medicine: background and perspectives]. / La relación del médico y sus pacientes en la medicina de nuestro tiempo: antecedentes y perspectivas.

In the last decades, demographic, economic and social changes along with the explosive development of scientific and technological aspects in medicine have modified public expectations in health care. The doctor-patient relation has been modified accordingly. Access of all patients to the most sophisticated medical care seems increasingly difficult and may be considered utopic. Thus, education of both medical students and general public must be urgently directed towards the primary and secondary prevention of most common diseases. The doctor-patient relation must be strengthened in the framework of a solid humanistic and scientific basis.

[Biliary lipid secretion in men with cholelithiasis]. / Secreción de lípidos biliares en hombres con colelitiasis.

Supersaturation of bile is indispensable for the appearance of cholesterol gallstones; it can be due to hypersecretion of cholesterol or to hyposecretion of bile acids and phospholipids. In a previous study we demonstrated cholesterol hypersecretion in Chilean women with gallstones. To elucidate the secretory defect in male patients we studied two groups of young men with normal body weight and a functioning gallbladder: four individuals with cholesterol gallstones and six healthy volunteers. The bile acid pool size and the secretory rate of bile acids and phospholipids were similar in controls and gallstone patients. On the other hand, cholesterol output was higher in the gallstone group. This study confirms the importance of biliary cholesterol hypersecretion as a major factor in the pathogenesis of gallstone disease in Chile.

[Biliary scintigraphy in patients with functional disorders of Oddi's sphincter]. / Cintigrafia biliar en pacientes con alteraciones funcionales del esfinter de Oddi.

The appearance of biliary pain after cholecystectomy in patients with normal ultrasonic and cholangiographic studies has been attributed to functional alterations of the Sphincter of Oddi. We performed dynamic cholescyntigraphic studies of the biliary tract in 32 cholecystectomized patients, at least six months after the operation: 27 were asymptomatic (control group) and 5 had clinical and laboratory findings suggesting temporary functional obstruction of the Sphincter of Oddi. In this group we demonstrated an emptying delay of the biliary tract that was modified by the IV infusion of Cholecystokinin Octapeptide. Biliary Cholescintigraphy appears as a good screening method to evaluate functional alterations of the Sphincter of Oddi.