Anterior approach for pediatric supracondylar humerus fractures: A systematic review.

BACKGROUND AND PURPOSE: Open reduction is rarely performed in pediatric supracondylar humerus fractures. However, clear evidence is lacking regarding the optimal open approach to achieve satisfactory results. The anterior approach provides direct visualization of the fracture and excellent exposure to neurovascular structures, although its utilization is less common. The objective of this study was to review the indications, outcomes, and complications associated with the anterior approach for open reduction of these fractures. METHODS: Our protocol was registered at PROSPERO: CRD42023446923. MEDLINE/PubMed, Embase, Web of Science, Clinicaltrials.gov, and Cochrane Library were searched from database inception to search date (December 2023) and screened in duplicate for relevant studies. Data were collected regarding patient demographics, indications for open reduction, Flynn's functional and cosmetic outcomes, and complications. Study quality was assessed using the Methodological Index for Non-Randomized Studies Criteria. RESULTS: A total of 19 studies involving 483 patients were included. One study was classified as Level 2 evidence, ten as Level 3, and eight as Level 4. The mean MINORS score was 13.05±3.47. The primary indication for open reduction was failed closed reduction, observed in 46% of patients. 97.7% and 98.6% of patients achieved Flynn's functional and cosmetic satisfactory results, respectively. The postsurgical neurovascular injury rate was 1.4%. One patient required reintervention. CONCLUSION: The anterior approach is safe and effective for managing pediatric supracondylar humerus fractures requiring open reduction. LEVEL OF EVIDENCE: Systematic review of Level 2-4 evidence studies.

Diagnóstico oftalmológico del síndrome de linfedema-distiquiasis a través de la mutación FOXC2 / Ophthalmologic diagnosis of lymphedema-distichiasis syndrome through the FOXC2 mutation

El síndrome de linfedema-distiquiasis es uno de los fenotipos más frecuentes de aparición de linfedema primario; aun así, su prevalencia es baja.Este síndrome cursa con la aparición en la infancia o en la pubertad de pestañas aberrantes y otras formas de distiquiasis que pueden disminuir la calidad de vida, especialmente en pacientes en edades tan tempranas. La valoración clínica de este tipo de signos debe hacernos tener en mente este grupo de síndromes, ya que contamos, en este caso, con el diagnóstico de certeza gracias al análisis genético en suero del gen FOXC2, como ocurre en el caso que presentamos.De esta manera podemos prevenir, diagnosticar y tratar tanto los síntomas oftalmológicos como el resto de los síntomas sistémicos de forma precoz y más efectiva, aumentando así la calidad de vida de nuestros pacientes. (AU)

Lymphedema-distichiasis syndrome is one of the most frequent phenotypes of primary lymphedema, even so, its prevalence is still low.This syndrome courses with the appearance of abnormal eyelashes and distichiasis during childhood or puberty. This can cause a notable discomfort on our patients, especially at such an early age. The clinic evaluation of this signs must make us have in mind this group of syndromes, because in the case of lymphedema distichiasis syndrome, we can certainly diagnose it with the genetic analysis of the FOXC2 gen on patient's serum.With this we could prevent, diagnose and treat the ophthalmologic syndrome alongside the rest of systemic symptoms of this syndrome in a more effective way, giving our patients a higher quality of life. (AU)

Ophtalmologic diagnosis of lymphedema-distichiasis syndrome through the FOXC2 mutation.

Lymphedema distichiasis syndrome is one of the most frequent phenotypes of primary lymphedema, even so, its prevalence is still low. This syndrome courses with the appearance of abnormal eyelashes and distichiasis during childhood or puberty. This can cause a notable discomfort on our patients, especially at such an early age. The clinic evaluation of this signs must make us have in mind this group of syndromes, because in the case of lymphedema distichiasis syndrome, we can certainly diagnose it with the genetic analysis of the FOXC2 gen on patient's serum. With this we could prevent, diagnose and treat the ophthalmologic syndrome alongside the rest of systemic symptoms of this syndrome in a more effective way, giving our patients a higher quality of life.

[Translated article] Insertion of S1 iliosacral screws in the computed tomography room: An alternative to improve safety in the percutaneous management of posterior pelvic ring injuries.

INTRODUCTION: The main complication of percutaneous iliosacral screw fixation is implant malposition, which can lead to vascular and nerve damage. The anatomical variability of the sacrum can make screw insertion difficult under fluoroscopic guidance. Among the methods described to improve the accuracy of this technique, stands out the use of computed tomography (CT). The aim of this study is to compare the results of iliosacral screw insertion with fluoroscopy or CT navigation. METHODOLOGY: Retrospective cohort study of 66 iliosacral screws in 56 patients during 11 years. The screws were inserted with fluoroscopy in the operating room or with CT in the radiodiagnosis area. We collected data on patient characteristics, lesions, treatment, and clinical and radiological results. RESULTS: Forty-seven screws were inserted with fluoroscopy and 19 with CT. A percentage of 18.2 of screws perforated the S1 osseous corridor. All of them were inserted with fluoroscopy guidance (0 vs. 34%; p<0.01). Those operated with CT accumulated more sacral dysmorphism criteria than those operated with fluoroscopy (2.2 vs. 1.6; p=0.02). The S1 corridor on the axial CT view was narrower in those in whom perforation had occurred (18.8 vs. 21.0mm; p=0.02). Two cases with perforation developed S1 radiculalgia. Two endopelvic screws had to be removed. CONCLUSION: We advise the use of CT guidance for iliosacral screw insertion in patients with sacral dysmorphism or narrow S1 corridors in facilities where other navigation methods are not available.

Insertion of S1 iliosacral screws in the computed tomography room: An alternative to improve safety in the percutaneous management of posterior pelvic ring injuries. / Inserción de tornillos iliosacros S1 en la sala de tomografía computarizada. Una alternativa para mejorar la seguridad en el tratamiento percutáneo de las lesiones posteriores del anillo pélvico.

INTRODUCTION: The main complication of percutaneous iliosacral screw fixation is implant malposition, which can lead to vascular and nerve damage. The anatomical variability of the sacrum can make screw insertion difficult under fluoroscopic guidance. Among the methods described to improve the accuracy of this technique, stands out the use of computed tomography (CT). The aim of this study is to compare the results of iliosacral screw insertion with fluoroscopy or CT navigation. METHODOLOGY: Retrospective cohort study of 66 iliosacral screws in 56 patients during 11 years. The screws were inserted with fluoroscopy in the operating room or with CT in the radiodiagnosis area. We collected data on patient characteristics, lesions, treatment, and clinical and radiological results. RESULTS: Forty-seven screws were inserted with fluoroscopy and 19 with CT. A percentage of 18.2 of screws perforated the S1 osseous corridor. All of them were inserted with fluoroscopy guidance (0 vs. 34%; p<0.01). Those operated with CT accumulated more sacral dysmorphism criteria than those operated with fluoroscopy (2.2 vs. 1.6; p=0.02). The S1 corridor on the axial CT view was narrower in those in whom perforation had occurred (18.8 vs. 21.0mm; p=0.02). Two cases with perforation developed S1 radiculalgia. Two endopelvic screws had to be removed. CONCLUSION: We advise the use of CT guidance for iliosacral screw insertion in patients with sacral dysmorphism or narrow S1 corridors in facilities where other navigation methods are not available.

Lead(ii) soaps: crystal structures, polymorphism, and solid and liquid mesophases.

The long-chain members of the lead(ii) alkanoate series or soaps, from octanoate to octadecanoate, have been thoroughly characterized by means of XRD, PDF analysis, DSC, FTIR, ssNMR and other techniques, in all their phases and mesophases. The crystal structures at room temperature of all of the members of the series are now solved, showing the existence of two polymorphic forms in the room temperature crystal phase, different to short and long-chain members. Only nonanoate and decanoate present both forms, and this polymorphism is proven to be monotropic. At higher temperature, these compounds present a solid mesophase, defined as rotator, a liquid crystal phase and a liquid phase, all of which have a similar local arrangement. Since some lead(ii) soaps appear as degradation compounds in oil paintings, the solved crystal structures of lead(ii) soaps can now be used as fingerprints for their detection using X-ray diffraction. Pair distribution function analysis on these compounds is very similar in the same phases and mesophases for the different members, showing the same short range order. This observation suggests that this technique could also be used in the detection of these compounds in disordered phases or in the initial stages of formation in paintings.

Aquaporin 3 (AQP3) participates in the cytotoxic response to nucleoside-derived drugs.

BACKGROUND: Nucleoside analogs used in the chemotherapy of solid tumors, such as the capecitabine catabolite 5'-deoxy-5-fluorouridine (5'-DFUR) trigger a transcriptomic response that involves the aquaglyceroporin aquaporin 3 along with other p53-dependent genes. Here, we examined whether up-regulation of aquaporin 3 (AQP3) mRNA in cancer cells treated with 5'-DFUR represents a collateral transcriptomic effect of the drug, or conversely, AQP3 participates in the activity of genotoxic agents. METHODS: The role of AQP3 in cell volume increase, cytotoxicity and cell cycle arrest was analyzed using loss-of-function approaches. RESULTS: 5'-DFUR and gemcitabine, but not cisplatin, stimulated AQP3 expression and cell volume, which was partially and significantly blocked by knockdown of AQP3. Moreover, AQP3 siRNA significantly blocked other effects of nucleoside analogs, including G1/S cell cycle arrest, p21 and FAS up-regulation, and cell growth inhibition. Short incubations with 5-fluorouracil (5-FU) also induced AQP3 expression and increased cell volume, and the inhibition of AQP3 expression significantly blocked growth inhibition triggered by this drug. To further establish whether AQP3 induction is related to cell cycle arrest and apoptosis, cells were exposed to long incubations with escalating doses of 5-FU. AQP3 was highly up-regulated at doses associated with cell cycle arrest, whereas at doses promoting apoptosis induction of AQP3 mRNA expression was reduced. CONCLUSIONS: Based on the results, we propose that the aquaglyceroporin AQP3 is required for cytotoxic activity of 5'-DFUR and gemcitabine in the breast cancer cell line MCF7 and the colon adenocarcinoma cell line HT29, and is implicated in cell volume increase and cell cycle arrest.

Functional analysis of the human concentrative nucleoside transporter-1 variant hCNT1S546P provides insight into the sodium-binding pocket.

SLC28 genes, encoding concentrative nucleoside transporter proteins (CNT), show little genetic variability, although a few single nucleotide polymorphisms (SNPs) have been associated with marked functional disturbances. In particular, human CNT1S546P had been reported to result in negligible thymidine uptake. In this study we have characterized the molecular mechanisms responsible for this apparent loss of function. The hCNT1S546P variant showed an appropriate endoplasmic reticulum export and insertion into the plasma membrane, whereas loss of nucleoside translocation ability affected all tested nucleoside and nucleoside-derived drugs. Site-directed mutagenesis analysis revealed that it is the lack of the serine residue itself responsible for the loss of hCNT1 function. This serine residue is highly conserved, and mutation of the analogous serine in hCNT2 (Ser541) and hCNT3 (Ser568) resulted in total and partial loss of function, respectively. Moreover, hCNT3, the only member that shows a 2Na(+)/1 nucleoside stoichiometry, showed altered Na(+) binding properties associated with a shift in the Hill coefficient, consistent with one Na(+) binding site being affected by the mutation. Two-electrode voltage-clamp studies using the hCNT1S546P mutant revealed the occurrence of Na(+) leak, which was dependent on the concentration of extracellular Na(+) indicating that, although the variant is unable to transport nucleosides, there is an uncoupled sodium transport.

Structural determinants for rCNT2 sorting to the plasma membrane of polarized and non-polarized cells.

rCNT2 (rat concentrative nucleoside transporter 2) (Slc28a2) is a purine-preferring concentrative nucleoside transporter. It is expressed in both non-polarized and polarized cells, where it is localized in the brush border membrane. Since no information about the domains implicated in the plasma membrane sorting of rCNT2 is available, the present study aimed to identify structural and functional requirements for rCNT2 trafficking. The comprehensive topological mapping of the intracellular N-terminal tail revealed two main features: (i) a glutamate-enriched region (NPGLELME) between residues 21 and 28 that seems to be implicated in the stabilization of rCNT2 in the cell surface, since mutagenesis of these conserved glutamates resulted in enhanced endocytosis; and (ii) mutation of a potential protein kinase CK2 domain that led to a loss of brush border-specific sorting. Although the shortest proteins assayed (rCNT2-74AA, -48AA and -37AA) accumulated intracellularly and lost their brush border membrane preference, they were still functional. A deeper analysis of CK2 implication in CNT2 trafficking, using a CK2-specific inhibitor [DMAT (2-dimethylamino-4,5,6,7-tetrabromo-1H-benzimidazole)] and other complementary mutations mimicking the negative charge provided by phosphorylation (S46D and S46E), demonstrated an effect of this kinase on rCNT2 activity. In summary, the N-terminal tail of rCNT2 contains dual sorting signals. An acidic region is responsible for its proper stabilization at the plasma membrane, whereas the putative CK2 domain (Ser(46)) is implicated in the apical sorting of the transporter.

A jaw calibration method to provide a homogeneous dose distribution in the matching region when using a monoisocentric beam split technique.

PURPOSE: Asymmetric collimators are currently available in most of linear accelerators. They involve a lot of clinical improvements, such as the monoisocentric beam split technique that is more and more used in many external radiotherapy treatments. The tolerance established for each independent jaw positioning is 1 mm. Within this tolerance, a gap or overlap of the collimators up to 2 mm can occur in the half beams matching region, causing dose heterogeneities up to 40%. In order to solve this dosimetric problem, we propose an accurate jaw calibration method based on the Monte Carlo modeling of linac photon beams. METHODS: Simulating different jaw misalignments, the dose distribution occurring in the matching region for each particular configuration is precisely known, so we can relate the misalignment of the jaws with the maximum heterogeneity produced. From experimental measurements using film dosimetry, and taking into account Monte Carlo results, we obtain the actual misalignment of each jaw. By direct inspection of the readings of the potentiometers that control the position of the jaws, high precision correction can be performed, adjusting the obtained misalignments. RESULTS: In the linac studied, the dose heterogeneity in the junction performed with X jaws (those farther from the source), and 6 MV photon beam was initially over 12%, although each jaw was within the tolerance in position. After jaw calibration, the heterogeneity was reduced to below 3%. CONCLUSIONS: With this method, we are able to reduce the positioning accuracy to 0.2 mm. Consequently, the dose distribution in the junction of abutted fields is highly smoothed, achieving the maximum dose heterogeneity to be less than 3%.

Thermal and structural study of the crystal phases and mesophases in the lithium and thallium(i) propanoates and pentanoates binary systems: formation of mixed salts and stabilization of the ionic liquid crystal phase.

The temperature and enthalpy vs composition phase diagrams of the binary systems [xC(2)H(5)CO(2)Li + (1 - x)C(2)H(5)CO(2)Tl], and [x(n-C(4)H(9)CO(2)Li) + (1 - x)n-C(4)H(9)CO(2)Tl], where x is the mole fraction, were determined by DSC. Both binary systems display the formation of one 2:1 mixed salt each (at x = 0.667) that appear as a peritectic (incongruent melting) at T(fus) = 512.0 K, and T(fus) = 461.1 K, with Delta(fus)H(m) = 13.76 and 8.08 kJ.mol(-1) for Li-Tl (I) propanoates, and n-pentanoate mixed salts, respectively. The thermotropic liquid crystal of the thallium(I) n-pentanoate transforms into a more stable liquid-crystal phase, which appears in the phase diagram between 380 and 488 K and for x = 0 up to x = 0.56. The crystal structure of thallium(I) propanoate and of the two mixed salts were obtained via X-ray synchrotron radiation diffraction measurements. These compounds present a bilayered structure similar to the two pure lithium salts previously found by our group.

Different N-terminal motifs determine plasma membrane targeting of the human concentrative nucleoside transporter 3 in polarized and nonpolarized cells.

Human concentrative nucleoside transporter 3 (hCNT3) is a broad-selectivity, high-affinity protein implicated in the uptake of most nucleoside-derived anticancer and antiviral drugs. Regulated trafficking of hCNT3 has been recently postulated as a suitable way to improve nucleoside-based therapies. Moreover, the recent identification of a putative novel hCNT3-type transporter lacking the first 69 amino acids and retained at the endoplasmic reticulum anticipated that the N terminus of hCNT3 contains critical motifs implicated in trafficking. In the current study, we have addressed this issue by using deletions and site-directed mutagenesis and plasma membrane expression and nucleoside uptake kinetic analysis. Data reveal that 1) a segment between amino acids 50 and 62 contains plasma membrane-sorting determinants in nonpolarized cells; 2) in particular, the Val(57)-Thr(58)-Val(59) tripeptide seems to be the core of the export signal, whereas acidic motifs upstream and downstream of it seem to be important for the kinetics of the process; and 3) in polarized epithelia, the ß-turn-forming motif (17)VGFQ(20) is necessary for proper apical expression of the protein.

Link between high-affinity adenosine concentrative nucleoside transporter-2 (CNT2) and energy metabolism in intestinal and liver parenchymal cells.

Concentrative nucleoside transporter 2 (CNT2) is a high-affinity adenosine transporter that may play physiological roles beyond nucleoside salvage. Previous reports relate CNT2 function to modulation of purinergic signaling and energy metabolism in intestinal and liver parenchymal cells (Duflot et al., 2004, Mol Cell Biol 24:2710-2719; Aymerich et al., 2006, J Cell Sci 119:1612-1621). In the present study, to further examine the link between CNT2 and energy metabolism, CNT2 protein partners were identified using the bacterial two-hybrid and GST pull-down approaches. The N-terminal segment of CNT2 was used as bait, since proteins lacking this domain display impaired plasma membrane insertion and intracellular retention. Glucose-regulated protein 58 (GRP58) was identified as a potential rCNT2 partner in pull-down experiments. Two-hybrid screening performed against a liver human cDNA library led to the identification of aldolase B as another hCNT2 partner. Aldolase B-RFP and endogenous GRP58 separately co-localized with CNT2 in HeLa cells transfected with YFPrCNT2. CNT2 interaction with GRP58 was validated using co-immunoprecipitation experiments. In HeLa cells, fluorescence resonance energy transfer (FRET) efficiency increased upon fructose addition, consistent with a transient interaction between aldolase B and the transporter. The physiological basis for in vivo interactions was derived from experiments in which GRP58 was inhibited or overexpressed and aldolase B activity stimulated towards glycolysis. GRP58 appeared to be a negative effector of CNT2 function, whereas aldolase B flux modulated CNT2 activity via a mechanism involving acquisition of higher affinity for its substrates. These findings support the theory that CNT2 plays roles other than salvage and establishes links with energy metabolism.

The human concentrative nucleoside transporter-3 C602R variant shows impaired sorting to lipid rafts and altered specificity for nucleoside-derived drugs.

The human concentrative nucleoside transporter-3 C602R (hCNT3C602R), a recently identified human concentrative nucleoside transporter-3 (hCNT3) variant, has been shown to interact with natural nucleosides with apparent K(m) values similar to those of the wild-type transporter, although binding of one of the two sodium ions required for nucleoside translocation is impaired, resulting in decreased V(max) values (Mol Pharmacol 73:379-386, 2008). We have further analyzed the properties of this hCNT3 variant by determining its localization in plasma membrane lipid domains and its interaction with nucleoside-derived drugs used in anticancer and antiviral therapies. When expressed heterologously in HeLa cells, wild-type hCNT3 localized to both lipid raft and nonlipid raft domains. Treatment of cells with the cholesterol-depleting agent methyl-beta-cyclodextrin resulted in a marked decrease in hCNT3-related transport activity that was associated with the loss of wild-type hCNT3 from lipid rafts. It is noteworthy that although exogenously expressed hCNT3C602R was present in nonlipid raft domains at a level similar to that of the wild-type transporter, the mutant transporter was present at much lower amounts in lipid rafts. A substrate profile analysis showed that interactions with a variety of nucleoside-derived drugs were altered in the hCNT3C602R variant and revealed that sugar hydroxyl residues are key structural determinants for substrate recognition by the hCNT3C602R variant.

Curing and dynamic mechanical thermal properties of epoxy/clay nanocomposites.

Epoxy/Clay nanocomposites with two organically modified montmorillonites (Cloisite 30B and Cloisite 15A) have been prepared. Cloisite 15A has higher cation exchange capacity, interlayer spancing and hydrofobicity than Cloisite 30B. Different methods were carried out to disperse the clay in the epoxy monomer (diglycidyl ether of bisphenol A) with and without solvent, using stirring and ultrasound sonication. The epoxy hardeners used were 4,4'-diaminodiphenylmethane and 4,4'-diaminodiphenylsulfone which generate high glass transition temperature epoxy thermosets. The content of clay in the nanocomposites ranged from 2 to 11 wt%. The effect of Cloisites on the curing reaction has been studied by differential scanning calorimetry, finding that the presence of Cloisite 30B accelerates the curing reaction. The glass transition temperature of the epoxy thermoset decreases when the clay content increases, due to the plasticizing effect of the alkylammonium cations. The dispersion of the layered silicates within the crosslinked epoxy matrix was studied by wide-angle X-ray diffraction. In all the cases, the nanocomposites show intercalated clay structures, being the interlayer clay spacing almost independent of the method of dispersion, of the clay content, and of hardener used. Moreover the d-spacing differences between C30B and C15A nanocomposites are insignificant. Epoxy molecules intercalate in a smaller proportion in C15A than in C30B, as it was deduced from the increase of the d-spacing. The dynamic mechanical thermal properties of these nanocomposites were also investigated. Nanocomposites with Cloisite 30B show higher values of storage modulus than neat epoxy, both in the glassy and in the rubbery states. However Cloisite 15A does not improve the epoxy storage modulus, and such divergent behavior agrees with the different intercalation of epoxy in the clays. The fracture surfaces of the nanocomposites analyzed by environmental scanning electron microscopy indicate an improvement of toughness.

Structural and thermodynamic study on short metal alkanoates: lithium propanoate and pentanoate.

Lithium propanoate and pentanoate were characterized by DSC, single crystal and powder XRD and FTIR and impedance spectroscopies. Lithium propanoate presents a solid-to-solid transition (SII-SI) at T(ss) = (549.1 +/- 0.7) K on first heating that varies on the second and next ones, followed by a fusion at T(f) = (606.1 +/- 0.5) K. For lithium pentanoate, two solid-to-solid transitions (SIII-SII and SII-SI), at T(ss) = (205.5 +/- 0.5) K and T(ss) = (325.2 +/- 0.7) K, respectively, and a melting point at T(f) = (576.5 +/- 0.3) K were found. The crystal structures for both compounds were characterized at 100 and 298 K (and for the lithium propanoate also at 160 K). Single-crystal XRD showed that the SII phase of both compounds has a monoclinic structure with the same symmetry group (P2(1)/c). This is the first time that a single-crystal structure has been reported for any member of the lithium alkanoates series, so far. FTIR and impedance spectroscopies were also carried out to better characterize the solid phases in these compounds.

Nucleoside transporter proteins.

Concentrative nucleoside transporters (CNT; SLC28) and equilibrative nucleoside transporters (ENT; SLC29) mediate the uptake of natural nucleosides and a variety of nucleoside-derived drugs, mostly used in anticancer therapy. SLC28 and SLC29 families consist in three and four members, respectively, which differ in their substrate selectivity and their energy requirements. Tissue distribution of these transporters is not homogeneous among tissues, and their expression can be regulated. In epithelia, CNT and ENT proteins are mostly localized in the apical and basolateral membranes, respectively, which results in nucleoside and nucleoside-derived drugs vectorial flux. Nucleoside transporters can play physiological roles other than salvages, such as the modulation of extracellular and intracellular adenosine concentrations. Moreover, these transporters also have clinical significance. ENT proteins are target of dipyridamole and dilazep, used as vasodilatory drugs in the treatment of heart and vascular diseases. On the other hand, nucleoside transporters are responsible for the cellular uptake of currently used anticancer nucleoside-derived drugs, thus these membrane proteins might play a significant role in nucleoside-based chemotherapy. Finally, several polymorphisms have been described in CNT and ENT proteins that could affect nucleoside homeostasis, adenosine signalling events or nucleoside-derived drug cytotoxicity or pharmacokinetics.

Immunohistochemical evaluation of ProEx C in human papillomavirus-induced lesions of the cervix.

AIMS: Considering the sparse information about the clinical utility of the novel immunohistochemical marker ProEx C in histological sections, a decision was taken to study the pattern of ProEx C expression in normal/benign cervical epithelium (N/B), low-grade squamous intraepithelial lesion (LGSIL) and high-grade squamous intraepithelial lesion (HGSIL), as well as the association of ProEx C expression with human papillomavirus (HPV) genotypes. METHODS: 100 cervical samples, including 21 N/B cervices, 16 LGSILs, 61 HGSILs and two cervical invasive carcinomas, were obtained from conisation and hysterectomy. Surgical specimens were arranged in three tissue microarrays and stained for ProEx C. Ninety-three samples were HPV genotyped. Genotyping was performed by DNA amplification and hybridisation with genotype-specific probes on a low-density DNA array. RESULTS: ProEx C-positive expression in more than the lower third of the epithelium was observed in 14.3% of N/B, 62.5% of LGSIL and 90.2% of HGSIL. Seventy percent of HPV positivity was found in cases with expression in more than the lower third of the epithelium. Of 31 cases that were positive for HPV16, 16.1% showed ProEx C expression restricted to one or two basal layers, and 83.9% showed ProEx C expression in more than the lower third of the epithelium. CONCLUSIONS: ProEx C is significantly associated with HPV16 infection and is a useful adjunct in the identification of LGSIL and HGSIL in histological sections when expressed in more than the lower third of the epithelium.

Síndrome hemolítico urémico asociado a infección intestinal por Escherichia coli productora de shigatoxina (STEC) en pacientes chilenos: aspectos clínicos y epidemiológicos / Hemolytic uremic syndrome associated to shigatoxin producing Escherichia coli in Chilean children: clinical and epidemiological aspects

Clinical and epidemiological aspects of shigatoxin producing E. coli (STEC) infections and hemolytic uremic syndrome (HUS) are reviewed. Surveillance results from 14 sentinel centers during 2000-2002 showed a mean incidence rate of 3.4 HUS cases per 100.000 children, with the highest incidence in the 6 to 28 month age group. Disease is endemic with summer peaks. Between 1988 and 2002 we obtained the clinical characteristics of a group of 119 HUS children with the following results: mean age 16 months, bloody diarrhea 57.8 percent, no previous diarrhea 9 percent, 60 percent received antibiotics, 72 percent had oligoanuria, 53 percent required dialysis, 15 percent had seizures and 31 percent had dizziness; mortality was 3 percent. Four foodborne outbreaks have been detected in Santiago, two outbreaks occurred in household settings, one in a Day Care Center and one in a Neonatal Unit. Recommendations for diagnosis, treatment and prevention of STEC infections, including potential vaccines are discussed.

Se revisan y actualizan aspectos clínicos y epidemiológicos de las infecciones por Escherichia coli productora de shigatoxina (STEC), y el síndrome hemolítico urémico (SHU). Se incluyen resultados de una vigilancia de SHU en 14 centros centinelas (2000-2002), que mostró una incidencia promedio de 3,4 casos por 100.000 niños, 78 por ciento) en el grupo de 6 a 48 meses. Esta vigilancia reflejó una situación endémica, con aumento en verano. Se analiza la observación clínica protocolizada de 119 pacientes con SHU hospitalizados en la Región Metropolitana (RM) (1988 y 2002). Edad promedio: 16 meses. El 578 por ciento> tenía diarrea con sangre, 9 por ciento> no tenía diarrea previa, 60 por ciento> recibió antibacterianos, 72 por ciento> presentó oligoanuria y 53 por ciento> necesitó diálisis. El 31 por cientoo tuvo compromiso de conciencia y 15 por cientoo presentó convulsiones. Letalidad 3 por ciento. Se analizan brotes de STEC asociados a alimentos ocurridos en la RM en el hogar (2), un jardín infantil (1) y en un servicio de neonatología (1). Finalmente, se entregar recomendaciones para el manejo clínico y prevención, se revisan los criterios diagnósticos, nuevas estrategias terapéuticas y progresos en el desarrollo de vacunas.

Identification of TIGAR in the equilibrative nucleoside transporter 2-mediated response to fludarabine in chronic lymphocytic leukemia cells.

BACKGROUND: The nucleoside analogue fludarabine is used in the treatment of chronic lymphocytic leukemia. It triggers p53-mediated apoptosis, although the mutational status of p53 does not fully account for heterogeneity in responsiveness to treatment. The aim of this study was to identify new genes implicated in fludarabine action as well as to determine the role of equilibrative nucleoside transporters (ENT) in the transcriptomic response triggered by this drug in chronic lymphocytic leukemia cells bearing wild type p53. DESIGN AND METHODS: We performed gene expression profiling in cells from two fludarabine-sensitive and two fludarabine-resistant cases of chronic lymphocytic leukemia treated with fludarabine either in the presence or the absence of nitrobenzylthioinosine, a hENT1-specific blocker. Twenty selected fludarabine-inducible genes were validated using Taqman low-density arrays in cells from 20 chronic lymphocytic leukemia patients with the same experimental design. RESULTS: Sixteen of the twenty genes (DDB2, GADD45A, TYMS, BAX, TIGAR, FAS, TNFSF7, TNFSF9, CCNG1, CDKN1A, MDM2, SESN1, MAP4K4, PPM1D, OSBPL3 and WIG1) correlated with the ex vivo sensitivity of chronic lymphocytic leukemia cells to fludarabine, TIGAR (TP53-induced glycolysis and apoptosis regulator) being the gene that showed the strongest correlation (p<0.0001; r2= 0.6022).We observed that the transcriptomic response was weakly sensitive to the hENT1 blocker nitrobenzylthioinosine. Interestingly, we also found a correlation between hENT2 expression and induction of TIGAR after fludarabine treatment. CONCLUSIONS: We demonstrate a correlation between the recently described p53-inducible apoptosis gene TIGAR and both sensitivity to fludarabine and hENT2 expression in chronic lymphocytic leukemia cells. These results, as well as the variability in fludarabine response among chronic lymphocytic leukemia patients with wild type p53, support the major role of hENT2 in the uptake of fludarabine into chronic lymphocytic leukemia cells.