Projectes d’autoaprenentatge de Biologia Cel·lular a la Llicenciatura de Medicina

Aquest projecte de MQD ha permès realitzar una sèrie d’experiències diverses i valuoses que han apuntat formes alternatives en la docència de la Biologia Cel·lular i l’aprenentatge de l'estudiant de la llicenciatura o del grau de medicina. En base a la valoració qualitativa del grau de satisfacció dels usuaris i en un estudi antitatiu de la seva opinió, considerem que ha estat experiències molt vàlides que afavoreixen que l’alumne participi de forma més activa en la seva formació. La principal dificultat observada ha estat o millor dit serà, l’aplicació de les experiències desenvolupades, de forma obligatòria i generalitzada, a tots els alumnes, sobretot als de 1er curs, donat que es tracta d’un grup molt nombrós (més de 300 alumnes). De totes maneres l’experiència adquirida ha estat molt favorable. Les activitats desenvolupades es continuen aplicant i es continuaran aplicant en el nou pla de medicina. Una aplicació perllongada en cursos successius afavorirà poder extreure’n conclusions de tipus més quantitatiu a més de les apreciacions qualitatives.

High-field (3T) magnetic resonance defecography with functional assessment of the evacuation phase : a pictorial essay : P10

Purpose: Dynamic high-field magnetic resonance (MR) defecography including the evacuation phase is a promising tool for the assessment of functional pelvic disorders, nowadays seen with increasing frequency in elderly women in particular. Learning objectives: 1. To describe the adequate technique of dynamic high-field MRI (3T) in assessing pelvic floor disorders. 2. To provide an overview of the most common pathologies occurring during the evacuation phase, especially in comparison with results of conventional defecography. Methods and materials: After description of the ideal technical parameters of MR defecography performed in supine position after gel rectal filling with a 3 Tesla unit and including the evacuation phase we stress the importance of using a standardized evaluation system for the exact assessment of pelvic floor pathophysiology. Results: The typical pelvic floor disorders occurring before and/or during the evacuation phase, such as sphincter insufficiency, vaginal vault and/or uterine prolapse, cystourethrocele, peritoneo-/ entero-/ sigmoïdocele or rectal prolapse, are demonstrated. The difference between the terms "pelvic floor descent" and "pelvic floor relaxation" are pictorially outlined. MR results are compared with these of conventional defecography. Conclusion: Exact knowledge about the correct technique including the evacuation phase and the use of a standardized evaluation system in assessing pelvic floor disorders by dynamic high-field MRI is mandatory for accurate and reproducible diagnosis.

Molecular identification of similar species of the genus Biomphalaria (Mollusca: Planorbidae) determined by a polymerase chain reaction-restriction fragment length polymorphism

The freshwater snails Biomphalaria straminea, B. intermedia, B. kuhniana and B. peregrina, are morphologically similar; based on this similarity the first three species were therefore grouped in the complex B. straminea. The morphological identification of these species is based on characters such as vaginal wrinkling, relation between prepuce: penial sheath:deferens vas and number of muscle layers in the penis wall. In this study the polymerase chain reaction restriction fragment length polymorphism technique was used for molecular identification of these molluscs. This technique is based on the amplification of the internal transcribed spacer regions ITS1 e ITS2 of the ribosomal RNA gene and subsequent digestion of these fragments by restriction enzymes. Six enzymes were tested: Dde I, Mnl I, Hae III, Rsa I, Hpa II e Alu I. The restriction patterns obtained with DdeI presented the best profile for separation of the four species of Biomphalaria. The profiles obtained with all the enzymes were used to estimate the genetic distances among the species through analysis of common banding patterns.

Long-term follow-up of four patients with Langer-Giedion syndrome: clinical course and complications.

Long-term observations of individuals with the so-called Langer-Giedion (LGS) or tricho-rhino-phalangeal type II (TRPS2) are scarce. We report here a on follow-up of four LGS individuals, including one first described by Andres Giedion in 1969, and review the sparse publications on adults with this syndrome which comprises ectodermal dysplasia, multiple cone-shaped epiphyses prior to puberty, multiple cartilaginous exostoses, and mostly mild intellectual impairment. LGS is caused by deletion of the chromosomal segment 8q24.11-q24.13 containing among others the genes EXT1 and TRPS1. Most patients with TRPS2 are only borderline or mildly cognitively delayed, and few are of normal intelligence. Their practical skills are better than their intellectual capability, and, for this reason and because of their low self-esteem, they are often underestimated. Some patients develop seizures at variable age. Osteomas on processes of cervical vertebrae may cause pressure on cervical nerves or dissection of cerebral arteries. Joint stiffness is observed during childhood and changes later to joint laxity causing instability and proneness to trauma. Perthes disease is not rare. Almost all males become bald at or soon after puberty, and some develop (pseudo) gynecomastia. Growth hormone deficiency was found in a few patients, TSH deficiency so far only in one. Puberty and fertility are diminished, and no instance of transmission of the deletion from a non-mosaic parent to a child has been observed so far. Several affected females had vaginal atresia with consequent hydrometrocolpos.

Valoración del estudio vesical y del tracto urinario superior en pacientes con citología urinaria positiva y pruebas de imagen negativas

Introducció: La citologia urinària positiva en context de cistoscopia sense evidència de tumor macroscòpic obliga a continuar el seu estudi. En el nostre centre es realitzen biòpsies vesicals múltiples normatitzades (BMN) i citologia ureteral selectiva en aquest casos. Material i mètodes: Estudi retrospectiu de 70 pacients amb citologia urinària positiva en absència de tumor macroscòpic. Es van avaluar els resultats de totes les biòpsies vesicals múltiples i les citologies ureterals selectives realitzades. Resultats: Es va diagnosticar CIS vesical em 45 (64,3%) pacients. Es va detectar citologia ureteral positiva em 12: cinc (7,2%) en el costat esquerre i set (10%) en el dret. Es va observar CIS vesical concomitant em 2 de 5 pacients amb PAP ureteral positiu esquerra i em 5 de 7 amb PAP ureteral positiu dret. Conclusions: La biòpsia múltiple normatitzada (BMN) és útil per a aquest casos. Els pobres resultats obtinguts en citologia ureteral selectiva posen en dubte la rendibilitat de la seva utilització sistemàtica.

Tumores parotídeos: revisión de la distribución demográfica y de la correlación cito-histológica de los pacientes intervenidos por el servicio de Cirugía Maxilofacial del Hospital Universitario Vall d’Hebron

Els tumors parotidis constitueixen un motiu de consulta freqüent en el medi hospitalari. Per conèixer l’origen cel•lular dels mateixos disposem de l’anàlisi citològic pre-quirúrgic. No existeix una correlació exacta entre la citologia pre-quirúrgica i l’anatomia patològica definitiva segons la literatura. S’ha realitzat un estudi retrospectiu de sèries de casos dels pacients atesos per tumors parotidis al servei de Cirurgia Maxil•lofacial de l’Hospital Vall d’Hebron en el qual s’ha avaluat la distribució demogràfica d’aquests tumors i la correlació cito-histològica comparant-la amb altres sèries.

Cirp function and characterisation in RNA and microRNAs

In order to search for novel genes involved in cell proliferation, the hypothesis was that by infecting primary cells with a cDNA library of immortal cells would render immortalizing genes. Consequently it has been discovered CIRP (Cold inducible RNA-binding protein). Mammalian cells exposed to mild hypothermia show a general inhibition of protein synthesis and a concomitant increase in the expression of a small number of cold-shock mRNAs and proteins. Rbm3, another RNA binding protein belonging to the same family, has been postulated to facilitate protein synthesis at mild cold shock. To investigate if the same occurs for CIRP, CIRP was overexpressed in primary cells and protein sintesis was measured. Interestingly, CIRP increased protein synthesis, however, such increase did not involve an increase in the polysome fraction or affected the ribosome profile. In addition, the effect caused by CIRP inhibition or knockdown was also analyzed. Different siRNAs against CIRP were tested. Once checked their efficiency by decreasing CIRP at mRNA and protein levels, proliferation was tested by BrdU, cell number (DAPI) and proliferation curves were performed. Interestingly, CIRP provoke a decreased proliferation in primary cells: MEFs, HMEC; and cancer cells: TERA2 and HeLa. In conclusion, we describe for the first time that CIRP bypasses replicative senescence when over-expressed at physiological temperature (37ºC) by increasing a general protein synthesis. This effect is achieved through ERK1/2 activation in MEFs.The decrease in growth rate found in mammalian cells treated with mild cold stress is not entirely attributable to arrested metabolism. This decrease may also involve an active process in which CIRP and other stress-responsive proteins play a fundamental role in stimulating proliferation. Although most cell proteins are down-regulated or inhibited with cold stress, CIRP is activated to maintain cells in an active proliferative status and its overexpression at 37°C might be potentially oncogenic.

Experimental transmission of Trypanosoma cruzi through the genitalia of albino mice

Trypanosoma cruzi is usually transmitted by contact with the excreta of infected Triatominae; among non-vectorial infections, direct transmission through coitus has been proposed. We investigated this possibility by instilling, through the external meatus of the vagina and the penis of previously anesthetized NMRI albino mice, blood of mice infected with strains isolated from Didelphis marsupialis (opossum, strain CO57), Rattus rattus (rat, strain CO22) and human (strain EP). Some animals were allowed to copulate the same day of the instillation. In other experiments, the strains were inoculated in the scrotum. To determine the effect of immunosuppression, some mice were treated with cyclophosphamide 30 days post-instillation. Controls were instilled orally and ocularly. Vaginal instillation with strain CO22 produced systemic infection with tropism to the heart, skeletal muscle, skin, duodenum, pancreas, ovary and sternum. Scrotal inoculation with strain EP likewise invaded liver, spleen, lung, lymph nodes and urogenital organs; while strain CO57 invaded skeletal and cardiac muscle, pancreas, testis, and vas deferens. Penile infection with strain CO22 was detected by xenodiagnosis. Immunosuppression did not increase parasitemia of vaginally infected mice or controls. Mating did not produce infection. Our results show that contact of blood trypomastigotes of T. cruzi with genital mucosa can produce blood and tissue infections. These results are discussed in relation to reports of frequent experimental tropism of T. cruzi toward urogenital organs.

Protocolo diagnóstico y seguimiento de la prevalencia e incidencia del virus del papiloma humano (vph) y las anormalidades citológicas de la mucosa anal de hombres que tienen sexo con hombres (hsh) e infección por el virus de la inmunodeficiencia humana (vih).

La citologia anal és un mètode sensible en el despistatge de la neoplàsia de canal anal i similar a la biòpsia dirigida mitjançant rectoscopi i tinció amb àcid acètic al 5%, sobretot en lesions d’alt grau de malignitat; a més de ser una prova adequada en el seguiment d’aquestes lesions. Els pacients VIH homes que tenen sexe amb altres homes tenen major incidència i prevalència de virus papiloma humà i major nombre d’anormalitats en la mucosa del canal anal que els VIH negatius.

Valor del ADN-VPH en el cribado de la población oportunista en el departamento 6 de Valencia

La infecció pel Virus del Papil.loma Humà (VPH) és la causa principal de gairebé tots els casos de càncer cervical. En països on s'apliquen de manera programada tècniques de detecció, hi ha una disminució de la incidència i la mortalitat del càncer cervical. La detecció del VPH és un avenç important per a la prevenció del càncer en permetre un diagnòstic precoç de lesions cancerígenes. És per això que, es va decidir estudiar durant un any a la població de pacients que acudien a les consultes de ginecologia i aplicar si estava indicat el protocol de detecció de l'ADN-VPH segons les indicacions de l’Asociació Espanyola de Patologia Cervical i Colposcopia (AEPCC) per després traure conclusions.

Pseudomonas aeruginosa: study of Antibiotic Resistance and Molecular Typing in Hospital Infection Cases in a Neonatal Intensive Care Unit from Rio de Janeiro City, Brazil

This study had the objective of to analyze the demographic and bacteriologic data of 32 hospitalized newborns in an neonatal intensive care unit of a public maternity hospital in Rio de Janeiro city, Brazil, seized by Pseudomonas aeruginosa sepsis during a period ranged from July 1997 to July 1999, and to determine the antimicrobial resistance percentage, serotypes and pulsed field gel electrophoresis (PFGE) patterns of 32 strains isolated during this period. The study group presented mean age of 12.5 days, with higher prevalence of hospital infection in males (59.4%) and vaginal delivery (81.2%), than females (40.6%) and cesarean delivery (18.8%), respectively. In this group, 20 (62.5%) patients received antimicrobials before positive blood cultures presentation. A total of 87.5% of the patients were premature, 62.5% presented very low birth weight and 40.6% had asphyxia. We detected high antimicrobial resistance percentage to b-lactams, chloramphenicol, trimethoprim/sulfamethoxazole and tetracycline among the isolated strains. All isolated strains were classified as multi-drug resistant. Most strains presented serotype O11 while PFGE analysis revealed seven distinct clones with isolation predominance of a single clone (75%) isolated from July 1997 to June 1998.

Biological variability in clinical isolates of Trichomonas vaginalis

Eighteen clinical isolates of Trichomonas vaginalis were obtained from women who attended health centers of the Goverment of Madrid. A total of 1,848 vaginal specimens recovered during the gynaecological examination were seeded in culture tubes containing liquid Diamond medium. Pathogenicity to mice was determined after intraperitoneal inoculation of mice by quantification of mortality and gross damage to abdominal organs. As could be expected, a broad variability was obtained, being some of the isolates more virulent than the reference strain. Regarding to metronidazole susceptibility, none resistant isolate was found but different degrees of susceptibility were determined.

Perspective of a new diagnostic for human trichomonosis

Several diagnostic techniques have been employed for the detection of Trichomonas vaginalis. Microtubules constitute the cytoskeleton in eukaryotic cells and are sensitive to antimitotic drugs, such as Taxol (paclitaxel). We used FLUTAX a fluorescent taxoid - to analyze the microtubule distribution in living trophozoites of T. vaginalis in urine and in vaginal discharge. A high intensity of fluorescence was observed in living T. vaginalis, epithelial cells and leukocytes present in urine and vaginal discharge. Our preliminary results show the perspective of a new diagnostic technique for trichomonosis and will contribute to the understanding of the cytoskeleton of T. vaginalis.

Fonctions du plancher pelvien: de la phase expulsive à la consultation du post-partum [Pelvic floor functions: from the beginning of the second phase of labor to the postpartum consultation].

Vaginal delivery can cause lesions of the various pelvic structures responsible for the mechanisms of continence. These lesions may perhaps be prevented in the future by measuring pressure generated during childbirth. Tear of the anal sphincter during childbirth is a marker of a global impairment of the urinary, ano-rectal and sexual pelvic functions in the short and medium term. Persistence of a defect of the anal sphincter is frequent in spite of immediate suture. The correlation between these defects and ano-rectal incontinence are not established in our experience. The quality of the contraction of the sphincter complex and pubo-rectal sling seems to play a more important role in ano-rectal continence after a traumatic childbirth.

Colposcopic evaluation after a repeat atypical squamous cells of undetermined significance (ASCUS) smear.

OBJECTIVES: Management of patients with atypical squamous cells of undetermined significance (ASCUS) remains controversial. We chose to repeat the Pap smear after four months. If ASCUS persisted in this second test, the patient was advised to undergo colposcopy. Our objective is to determine the clinical significance and the prediction of neoplasia among these patients through a colposcopic examination. METHODS: Of 29,827 patients who had a Pap smear, ASCUS were detected in 1387 (5%) and persisted in the repeat smear of 225 (16%). Colposcopy and an additional Pap smear were performed on 186 patients. RESULTS: Out of 186 colposcopic evaluations, 91 (49%) were normal and the patients had a negative Pap smear. Colposcopy was abnormal in 95/186 patients (51%) (Table 1). Histology of the directed biopsies revealed 38 (21%) low-grade squamous intraepithelial lesions (LSIL) and 17 (9%) high-grade squamous intraepithelial lesions (HSIL). Forty patients (21%) with normal biopsies had ASCUS for the third time in the Pap smear. CONCLUSIONS: Colposcopic evaluation after a repeated Pap smear with ASCUS is an appropriate cost-effective management. Finding 30% of LSIL or HSIL justifies this additional investigation.