Parasitological versus molecular diagnosis of strongyloidiasis in serial stool samples: how many?

Strongyloidiasis is usually an asymptomatic disease in immunocompetent patients, caused by Strongyloides stercoralis. However, in immunocompromised patients it can produce a severe clinical profile. Therefore, a correct diagnosis is necessary in these cases and in those chronic asymptomatic patients. The low sensitivity of classical parasitological techniques requires the analysis of multiple serial stool samples. Molecular diagnostic techniques represent an improvement in the detection of the parasite. The objective of this study was to evaluate the minimum number of samples necessary to achieve maximum sensitivity by real-time polymerase chain reaction (PCR). A total of 116 stool samples from 39 patients were analysed by direct microscopic observation, agar culture, Harada-Mori and real-time PCR, in one, two, three and four or more consecutive samples. After two serial samples, 6 out of 39 patients were positive by parasitological and molecular techniques, while 16 of them were real-time PCR positive, and all the patients detected by parasitology were also detected by the molecular technique, reaching 100.00% sensitivity versus 83.00% when analysing a single sample. These data also reflect apparently low specificity (51.52%) and positive predictive value (PPV) (27.27 %) values, due to the high number of cases detected by real-time PCR and not by parasitological techniques. These cases were confirmed as true positives when analysing three, four or more samples from the same patient. In conclusion, the application of molecular techniques decreases the number of serial stool samples necessary to give a diagnosis with the maximum sensitivity.

Factors affecting the viscosity of sodium hypochlorite and their effect on irrigant flow.

AIM: To assess the influence of concentration, temperature and surfactant addition to a sodium hypochlorite solution on its dynamic viscosity and to calculate the corresponding Reynolds number to determine the corresponding flow regimen. METHODOLOGY: The dynamic viscosity of the irrigant was assessed using a rotational viscometer. Sodium hypochlorite with concentrations ranging from 0.6% to 9.6% was tested at 37 and 22 °C. A wide range of concentrations of three different surfactants was mixed in 2.4% sodium hypochlorite for viscosity measurements. The Reynolds number was calculated under each condition. Data were analysed using two-way anova. RESULTS: There was a significant influence of sodium hypochlorite concentration (P < 0.001) and temperature (P < 0.001) on dynamic viscosity: the latter significantly increased with sodium hypochlorite concentration and decreased with temperature. A significant influence of surfactant concentration on dynamic viscosity (P < 0.001) occurred, especially for high surfactant concentrations: 6.25% for benzalkonium chloride, 15% for Tween 80 and 6.25% for Triton X-100. Reynolds number values calculated for a given flow rate (0.14 mL s(-1)), and root canal diameter (sizes 45 and 70) clearly qualified the irrigant flow regimen as laminar. CONCLUSIONS: Dynamic viscosity increased with sodium hypochlorite and surfactant concentration but decreased with temperature. Under clinical conditions, all viscosities measured led to laminar flow. The transition between laminar and turbulent flow may be reached by modifying different parameters at the same time: increasing flow rate and temperature whilst decreasing irrigant viscosity by adding surfactants with a high value of critical micellar concentration.

[Positive sentinel node risk in relation to oestrogen receptors in breast cancer in premenopausal and postmenopausal women]. / Relación entre el riesgo de metástasis en el ganglio centinela y los receptores estrogénicos en pacientes pre y posmenopáusicas con cáncer de mama.

OBJECTIVE: The influence of the relationship between pre- and post-menopausal stage of patients with breast cancer (BC) and the risk of sentinel lymph node (SLN) metastasis as well as the influence of oestrogen receptor (ER) status within each one of these groups were analyzed. METHODS: A BC database with 1,388 patients was analysed. Three age groups were studied: A, elderly postmenopausal, 200 patients, ≥ 70 years old; B, younger postmenopausal, 89 patients, 55-69 years old; C, premenopausal, 85 patients, <55 years old. In each group 2 subgroups were analyzed: positive ER and negative ER tumours. Data analysed: SLN-positive patients, non-sentinel node (NSN)-positive patients, non-surgical detections (NSD) and non disease-free (NDF) patients after a follow-up of 52 months. STATISTICAL ANALYSIS: chi-squared test, significance: P ≤ 0.05. RESULTS: SLN metastasis was significantly (P<0.025) more common in premenopausal than in postmenopausal patients, and within those, mainly in negative ER tumours. Positive-NSN increases slightly in premenopausal patients (exclusively in negative ER tumours). NDF patients are similar in the 3 groups and in all of them it is much more frequent in negative ER tumours. CONCLUSION: SLN metastasis varies significantly according to hormonal state and not according to age, being more frequent in premenopausal patients and mainly in ER negative tumours.

Stem cell-like transcriptional reprogramming mediates metastatic resistance to mTOR inhibition.

Inhibitors of the mechanistic target of rapamycin (mTOR) are currently used to treat advanced metastatic breast cancer. However, whether an aggressive phenotype is sustained through adaptation or resistance to mTOR inhibition remains unknown. Here, complementary studies in human tumors, cancer models and cell lines reveal transcriptional reprogramming that supports metastasis in response to mTOR inhibition. This cancer feature is driven by EVI1 and SOX9. EVI1 functionally cooperates with and positively regulates SOX9, and promotes the transcriptional upregulation of key mTOR pathway components (REHB and RAPTOR) and of lung metastasis mediators (FSCN1 and SPARC). The expression of EVI1 and SOX9 is associated with stem cell-like and metastasis signatures, and their depletion impairs the metastatic potential of breast cancer cells. These results establish the mechanistic link between resistance to mTOR inhibition and cancer metastatic potential, thus enhancing our understanding of mTOR targeting failure.

Risk of thrombosis during coronary angioplasty with low osmolality contrast media.

Studies in vitro have suggested that nonionic low osmolar contrast agents produce an increase in thrombogenicity. To determine the incidence of thrombi related to the use of nonionic low osmolar contrast media during coronary angioplasty, a double-blind randomized study was performed in 100 patients. Medication before angioplasty included oral aspirin (250 mg/day) in all cases. At the beginning of the procedure, aspirin (250 mg) and heparin (10,000 U) were intravenously administered. During the procedure patients were randomly assigned to receive either an ionic low osmolar contrast agent ioxaglate (n = 50), or a nonionic low osmolar contrast media iohexol (n = 50). The presence of thrombus was evaluated on the angiogram and on the guidewire immediately after its retrieval from the patients. Clinical, angiographic and procedural variables were similar in the 2 randomized groups. Angiographic evidence of thrombus was observed in 1 patient (2%) assigned to ioxaglate and in 11 patients (22%) assigned to iohexol (p less than 0.005). One patient (2%) from the ioxaglate group and 6 patients (12%) from the iohexol group showed thrombotic residues on the guidewire (p = not significant). Three patients had acute myocardial infarction, 1 patient (2%) receiving ioxaglate and 2 patients (4%) iohexol (p = not significant). There were no deaths. Thus, compared with an ionic low osmolar contrast media ioxaglate, the nonionic low osmolar contrast agent iohexol increases the incidence of thrombus during coronary angioplasty.

The prevalence of spondylolysis in the Spanish elite athlete.

The diagnosis of spondylolysis is a major cause of concern for patients and their families, especially when the patients are young athletes with promising futures in their sports. In this study, 3152 case histories of high-level athletes were evaluated to determine which sports had a higher prevalence of spondylolysis. The overall percentage of spondylolysis among athletes in this study (8.02%) was not very much higher than that among the general population, which varies between 3% and 7%. However, when each sport was considered separately we found much higher values for some sports, with the highest percentages occurring in throwing sports (26.67%), artistic gymnastics (16.96%), and rowing (16.88%). The analysis of the biomechanical movements involved in the sports with greater prevalence of spondylolysis has led us to include the element of torsion against resistance as another possible causative factor for spondylolysis that should be added to the already known causative mechanisms, lumbar hyperextension and rotation. We have divided the sports into three risk groups according to the prevalence of spondylolysis shown and the characteristics of the sample, and we recommend systematic radiological examination of the lumbar spine in athletes considered to be at greater risk of developing spondylolysis.

[Molecular changes in adenocarcinoma of the small intestine associated with Peutz-Jeghers syndrome]. / Alteraciones moleculares en adenocarcinoma de intestino delgado asociado a síndrome de Peutz-Jeghers.

The presence of molecular alterations in the c-K-ras and p53 genes in a small bowel adenocarcinoma arising in a case of Peutz-Jeghers syndrome is reported. The absence of mutations at codon 12 and 13 of the c-K-ras gene in the hamartoma and carcinoma indicates that this oncogene does not contribute to its development. On the other hand, p53 protein overexpression was detected in a small proportion (5-10%) of adenocarcinoma cells. Our findings suggest that p53 inactivation occur in late stages of tumour progression.

[Changes in the cellular proliferation of the healthy mucosa in patients with colorectal cancer]. / Alteraciones de la proliferación celular de la mucosa sana en pacientes con cáncer colorrectal.

AIM: To analyze differences in the proliferative pattern of normal mucosa between patients with colorectal cancer and healthy subjects. PATIENTS AND METHODS: By using flow cytometry we examined the proliferative pattern (Proliferative Index and S-Phase) in samples of normal mucosa from 34 patients operated on for colorectal cancer at our hospital and from 14 healthy subjects as a control group. RESULTS: All examined samples were diploid. The Proliferative Index and S-Phase in the Cancer Group were significantly higher than in the Control Group (16.7 +/- 5.9 vs 11.4 +/- 4, p < 0.003, and 11.9 +/- 3.9 us 6.6 +/- 3 p < 0.0004). CONCLUSIONS: These findings provide evidence for an altered proliferative pattern in the healthy colonic mucosa of patients with colorectal cancer.

Upper digestive tract dyspepsia and early gastric cancer.

AIM: The study of the frequency and evolution of upper digestive tract dyspepsia in a group of patients operated for early gastric cancer (EGC) and to perform a strategy of diagnosis for the patients with long term upper digestive tract dyspepsia. METHODS: Clinical data of 35 patients operated for EGC were retrospectively evaluated. The frequency, characteristics and evolution time of upper digestive tract dyspepsia, main when it began more than 6 months before surgery, were analyzed. Radiologic and endoscopic exams carried out for diagnosis were also evaluated. Histological diagnosis of surgical specimens were considered, looking for the presence of chronic atrophic gastritis, intestinal metaplasia, and peptic gastric ulcer. RESULTS: Long-term upper digestive tract dyspepsia was present in 27 patients (mean evolution time of 43.4 months). Clinical changes of previous symptoms that suggested gastric carcinoma were not found in 15 patients. Concurrent peptic gastric carcinoma were not found in 15 patients. Concurrent peptic gastric ulcer along with EGC was diagnosed by histology in 11 patients, and chronic atrophic gastritis and intestinal metaplasia were both present in the non-tumoral gastric mucosa in all cases. CONCLUSIONS: 1) Unspecific upper digestive tract dyspepsia is frequently found in patients with EGC. 2) Endoscopy should be the first exam performed in patients with upper digestive tract dyspepsia. 3) The patients with gastric ulcer, chronic atrophic gastritis or intestinal metaplasia must be submitted to sequential endoscopic follow-up.

Elastofibroma dorsi: clinical and pathologic aspects of two cases.

Elastofibroma dorsi is a benign entity that occurs most often in the subscapular area in elderly women. It has been a subject of controversy whether elastofibroma is a true neoplasm or a reactive fibrous lesion that produces abnormal elastic fibers. A biopsy should be performed to rule out sarcoma in all cases, but definitive treatment only requires simple surgical excision. We report two cases of elastofibroma and discuss the most relevant clinical and pathologic aspects.

[Lingual hamartoma]. / Hamartoma lingual.

The hamartoma is a benign tumor resulting of a mixture of normal and mature tissues and cells, sitting on an organ or tissue showing identical cell components. From the perusal done of the bibliography they appear as rare malformations basically compound of fibrous tissue, fat, acini of salivary glands and smooth muscle.

Control microbiano de agua de mar mediante microfiltración / Microbial control of seawater by microfiltration

El agua de mar refinada aparece en la literatura científica reciente como una potencial ayuda terapéutica en el tratamiento de varias enfermedades en humanos y animales por su contenido de minerales y oligoelementos. En Colombia, Nicaragua y España se utiliza de forma natural por recogida de la orilla e ingesta; sin embargo, esto puede representar un riesgo para la salud por los problemas de contaminación microbiológica y química. Los tratamientos de control microbiano del agua de mar permiten mejorar su calidad microbiológica. Objetivo: comparar la eficiencia de tres métodos de control microbiano: microfiltración, exposición solar y cuarentena. Metodología: se recolectaron 30 muestras de agua de mar en recipientes de polietileno de alta densidad con capacidad de 20 litros, en tres lugares diferentes de la costa atlántica colombiana. Resultados: de 30 muestras recolectadas, 15 resultaron con en- terobacterias como E. coli y bacterias halófilas como Vibrio y Aeromonas. La microfiltración a través de cerámica de 0,5 μm produce una desinfección de 100% de las muestras, mientras que la cuarentena por cinco meses y la desinfección solar son efectivas en 66 y 21% respectivamente. Esta última requiere de ciertas condiciones climáticas para alcanzar la desinfección y solo permite el manejo de pequeños volúmenes. Discusión: Respecto de la contaminación química en ciertos lugares, que no es controlable por los métodos de desinfección, se recomienda recoger el agua en altamar, en lugares limpios, y realizar la microfiltración.

Recent scientific literature presents seawater as a potential aid to solve a variety of health diseases in animals and human beings because by means of its mineral and trace elements content. In Colombia, Nicaragua and Spain it is collected in a natural way from de shore and drunk; however, this can represent a health risk because of the problems related to chemical and microbiological contamination. Microbial control of seawater allows the improvement of its microbiological quality. Objective: to compare the efficiency of three microbial control methods: microfiltration, solar exposition and quarantine. Methodology: 30 samples were collected in 20-liter high density polyethylene containers in three different places in the Colombian Atlantic coast. Results: 15 samples out of 30 showed the presence of bacteria such as E. coli and halophiles bacteria like Vibrio and Aeromonas. Microfiltration through ceramic filters of 0.5 μm produces disinfection in 100% of the samples but the quarantine for five months and solar disinfection are effective in 66 and 21% respectively. The latter requires certain weather conditions to achieve disinfection and it only allows managing small quantities of water. Dicussion: Considering chemical contamination in some places which cannot be controlled through disinfection methods, the collection of water offshore in clean places is suggested and then microfiltration treatment should be performed.

Structure of an isolated cerebellum and related nuclei developed within the matrix of a mature ovarian teratoma.

The distribution and organization of nerve cells in a microcerebellum and cerebellar stalk, developed within the matrix of a mature ovarian teratoma, were analyzed with respect to recent data on cerebellar histogenesis. It is postulated that a neuroectodermal germinal locus with proliferation capability similar to that found in the alar plates of the normal embryonic rhombencephalon was responsible for the formation of this highly organized neural tissue.