18F-choline PET/MRI on initial staging of prostate cancer. Impact on therapy approach. / La PET/RM con 18F-colina en el diagnóstico inicial del cáncer de próstata. Impacto en la estrategia terapéutica.

AIM: Evaluate the therapy impact of initial staging in patients diagnosed with prostate cancer by 18 F-choline PET/MRI hybrid technique. MATERIAL: A prospective study which included 31 patients diagnosed with prostate cancer; Gleason > 7; mean PSA 13.6 ng/mL (range 6.3-20.6). PET/MRI studies were acquired simultaneously with hybrid equipment (SIGNA.3T, GE) following intravenous injection of 185 ± 18.5MBq of 18F-choline: - Early/prostate imaging: PET emission + multiparametric MR: DIXON-T1-T2-diffusion-gadolinium. - Late/whole-body imaging: PET emission + MR: DIXON-T1-T2-diffusion-STIR sequences. Images were visually evaluated. SUV & ADC & textures were also calculated. Treatment selection was based upon Oncology Committee consensus decision. RESULTS: Procedure was well tolerated in all patients, and no artifacts were reported. MRI was superior in T staging in eight patients (25.8%) (Likert: 2-3), whereas PET increased MRI sensitivity in three patients (9.7%) (PIRADS: 3). PROSTATE LESION LOCATION: Peripheral 91.4%, transitional 8.6%. SUVmax threshold: 2.95: sensitivity 92.9%, specificity 66.7%. No correlation SUV vs. ADC. Better distinction between stage T2 vs. T3 using the DiscrLin model with NG = 16 (AUC 0.7767 ± 0.3386). PET was superior to T2 in textures analysis (0.588 vs. 0.412). Seventeen patients (54.8%) were staged ≥ T3, with surgical treatment being contraindicated. Fifteen patients (48.4%) presented with extra-prostatic disease: 8/31 oligometastatic and 7/31 multiple metastasis. Therapy approach following PET/MRI was: radical treatment in 24/31 patients (77.4%), 14 radical prostatectomy and 10 MRI-guided radiotherapy; systemic treatment in 7/31 patients (22.6%). CONCLUSION: 18F-choline PET/MRI had a complementary role for the T staging, with a high detection rate for NM infiltration. PET/MRI findings allowed patients to be directed either to prostatectomy or MRI-guided radiotherapy, and thus avoiding radicaltreatment in 22.6% of patients.

Standardization of acquisition protocols using PET/CT with 18F-Choline in prostate cancer. / Estandarización de los protocolos de adquisición mediante PET/TC con 18F-Colina en el cáncer de próstata.

AIM: To standardize acquisition protocols for 18F-Choline PET/CT to prevent from urine interference, to determine the best time point for the whole-body study, and to assess whether "dual point" acquisition allows for differentiating malignant vs. benign lesions. METHODS: One hundred consecutive patients with prostate cancer were prospectively studied. Immediately after 18F-Choline injection, a pelvis study was acquired, and a whole-body was subsequently obtained 1 and 2 hours p.i. Mean SUVmax was obtained in regions and for every sequential imaging. Mean analysis (χ2) and SUV percentage change (2/1 hours; 1 hours/0 min) were obtained. Metabolic pattern dynamics were assessed: accumulative vs. clearance. Patient follow-up after therapy and directed classification whenever ethically possible were performed. RESULTS: Fifty-three prostate foci, without disturbing urinary activity was ever found on early images. Accumulative pattern in 42, with percentage increase was: 0 min/1 hour: +16.7% (χ20.94); 1/2 hours: +10,0% (χ2 0.83). Clearance pattern in 11, with percentage decrease: 0 min/1 hour: -21.4% (χ20.91): -7.7% (χ20.85), corresponding in 7 to initial staging and in 4 post-radiotherapy biochemical recurrence. Every infradiaphragmatic uptake (n: 24) showed accumulative pattern, with percentage increase of +9.1% (χ20.97), all of them depicted on early imaging. As for 12 supradiaphragmantic uptake, 8 of them showed clearance pattern with percentage decrease: -13.0% (χ20.95). Accumulative pattern showed in 4 of them with percentage increase +13.0% (χ2 0.96), thus being assessed as invasive/malignant. Every bone uptake (n: 18) showed accumulative pattern, with percentage increase: +17.1% (χ20.95), all of them depicted on 1 hour imaging. CONCLUSIONS: As for prostate assessment is concerned, dual point at 0 min/1 hour proved to be the best procedure. As for supradiaphragmatic lymph-nodes detection, dual point with 1/2 hours performed best. As for infradiaphragmatic and bone involvement, as well as for inconclusive findings, the 2 hour imaging increased our diagnostic confidence.

Serum amyloid A and plasma fibrinogen concentrations in horses following emergency exploratory celiotomy.

BACKGROUND: Acute-phase proteins may help assess the nature and severity of lesions and outcome in horses undergoing colic surgery. OBJECTIVES: To compare serum amyloid A and plasma fibrinogen concentrations ([SAA] and [fibrinogen]) in the immediate post-operative period after exploratory celiotomy and determine their value in assessment of post-operative complications and survival to discharge. STUDY DESIGN: Observational study. METHODS: This study included horses over 1 year of age undergoing exploratory celiotomy. Surgical procedures, lesions, post-operative care, complications and survival to discharge were recorded. [SAA] and [fibrinogen] were measured prior to surgery and 5 days post-operatively. Statistical analyses included Yate's Chi-square test, linear mixed effects model, Mann-Whitney U test and logistic regression. RESULTS: Of 300 horses, 52.0% developed post-operative complications and 83.7% survived to discharge, with significantly reduced chance of survival in horses that developed post-operative complications (P<0.01). Median [SAA] at days 1, 2, 3, 4 and 5 and median [fibrinogen] at days 3, 4 and 5 were significantly different between horses that did and did not develop post-operative complications (P<0.05). Median [SAA] at days 1, 4 and 5 were significantly different between horses that did and did not survive to discharge (P<0.05). Logistic regression revealed post-operative complications to be associated with strangulating lesions (OR 2.35, 95% confidence interval [CI] 1.41-3.91, P≤0.001) and higher [fibrinogen] at admission (OR 1.21, 95% CI 1.00-1.45, P<0.05), and survival to discharge to be associated with lower [SAA] at 5 days post-operatively (OR 0.965, 95% CI 0.94-0.99, P = 0.002). MAIN LIMITATIONS: A large variety of lesions and complications prevented detailed analysis of associations between inflammatory markers, lesions and complications. CONCLUSIONS: Horses that develop post-operative complications have acute-phase responses of greater magnitudes and durations compared with those that do not develop complications. This is also seen in horses that do not survive to discharge. Measuring [SAA] daily and [fibrinogen] at admission, may help predict the development of post-operative complications.

[Clinical and molecular study in a family with multiple osteochondromatosis]. / Estudio clínico y molecular en una familia con osteocondromatosis múltiple.

We present two cases of a family with the diagnosis of multiple osteochondromatosis, which was confirmed by molecular study with nonsense in heterozygosis mutation c.1219CT, (p.Gln407Stop) in the EXT1 gene. In these cases, the Madelung deformity was presented in one patient as an uncommon finding and chondrosarcoma as a feared complication in the other case, highlighting intrafamilial variation, which is why individual and interdisciplinary evaluation is recommended. In addition, before a genetic entity should provide adequate and timely family genetic counseling to all its members.

Se presentan dos casos de una familia con diagnóstico de osteocondromatosis múltiple, el cual fue confirmado por estudio molecular con mutación sin sentido en heterocigosis c.1219CT, (p.Gln407Stop) en el gen EXT1. En el primer caso, en un paciente se presentó deformidad de Madelung como hallazgo infrecuente y en el otro caso, condrosarcoma como complicación temida, resaltando la variación intrafamiliar, por lo que se recomienda la evaluación individual e interdisciplinaria. Además, ante una entidad genética debe brindarse el adecuado y oportuno asesoramiento genético familiar a todos sus integrantes.

Estudio clínico y molecular en una familia con osteocondromatosis múltiple / Clinical and molecular study in a family with multiple osteochondromatosis

Resumen: Se presentan dos casos de una familia con diagnóstico de osteocondromatosis múltiple, el cual fue confirmado por estudio molecular con mutación sin sentido en heterocigosis c.1219C>T, (p.Gln407Stop) en el gen EXT1. En el primer caso, en un paciente se presentó deformidad de Madelung como hallazgo infrecuente y en el otro caso, condrosarcoma como complicación temida, resaltando la variación intrafamiliar, por lo que se recomienda la evaluación individual e interdisciplinaria. Además, ante una entidad genética debe brindarse el adecuado y oportuno asesoramiento genético familiar a todos sus integrantes.

Abstract: We present two cases of a family with the diagnosis of multiple osteochondromatosis, which was confirmed by molecular study with nonsense in heterozygosis mutation c.1219C>T, (p.Gln407Stop) in the EXT1 gene. In these cases, the Madelung deformity was presented in one patient as an uncommon finding and chondrosarcoma as a feared complication in the other case, highlighting intrafamilial variation, which is why individual and interdisciplinary evaluation is recommended. In addition, before a genetic entity should provide adequate and timely family genetic counseling to all its members.

The value of 11C-methionine PET in the early differentiation between tumour recurrence and radionecrosis in patients treated for a high-grade glioma and indeterminate MRI. / Utilidad de la PET con 11C-metionina en la diferenciación precoz entre recurrencia tumoral y radionecrosis de pacientes tratados de glioma de alto grado con RM indeterminada.

OBJECTIVE: To evaluate the contribution of 11C-Methionine PET in the early differentiation between tumour recurrence and radionecrosis in patients treated for a high grade glioma. METHOD: The study included 30 patients with glioma (III/IV grade) treated with surgery/radiotherapy/chemotherapy (5-8 months) and with an indeterminate MRI. All patients underwent a 11C-Methione PET (within 15 days of MRI) and studies were visually analysed (intensity and morphology of uptake), quantified (SUV max/SUV mean background), and coregistered to MRI (3D-Flair). Patient management was decided by the neuro-oncology committee to clinical and imaging follow-up, second-line treatment, or surgery. RESULTS: There were 23 11C-Methionine PET studies visually positive. Morphology of uptake was focal in 15, diffuse in 4, and ring-shaped in 4. Three out of the focal uptake cases underwent resection (Histopathology +). Sixteen underwent second-line therapy (11 responded; 5 progressed). The 4 cases with ring-shaped uptake were followed-up, and progression was found in 2 (true-positive), and disease-free in 2 (follow-up of 6 and 7 months, respectively) (false-positive). Seven out of 11C-Methionine studies PET were visually negative, and all of them were disease-free (follow-up of 3-12 months). SUV lesion/background was 2.79±1.35 in tumour recurrence, and 1.53±0.39 in radionecrosis (P<.05). Taking into account a SUV lesion/background threshold of 2.35, the sensitivity and specificity values were 90.5% and 100%, respectively. CONCLUSION: Visual analysis, quantitative and PET/MRI coregistration of 11C-Methionine PET showed their complementary role in patients with indeterminate MRI results, thus allowing early differentiation between tumour recurrence and radionecrosis, and helping in the individual therapy approach.

Peritoneal Cancer Index by (18)F-FDG PET/TC pre and post-hyperthermic intraperitoneal chemotherapy. Report of a case. / Peritoneal Cancer Index mediante (18)F-FDG PET/TC pre y poscirugía citorreductiva radical y quimioterapia intraperitoneal con hipertermia. A propósito de un caso.

Radical cytoreductive surgery followed by hyperthermic intraperitoneal chemotherapy increases survival in patients with end-stage peritoneal carcinomatosis, and who are under palliative therapy. The Peritoneal Cancer Index enables the tumor burden to be quantified during surgery, as well as treatment planning and patient prognosis. It is obtained by combining the tumor spread in 13 abdominal and pelvic regions with the largest tumor size. Fluorodeoxyglucose positron emission tomography/computed tomography is the technique of choice for those patients selected to undergo radical cytoreductive surgery followed by hyperthermic intraperitoneal chemotherapy, due to its higher detection rate of carcinomatosis, and since it allows extra-peritoneal disease staging. The simplified Peritoneal Cancer Index (9 regions defined by 2 transverse and 2 sagittal planes) obtained by fluorodeoxyglucose positron emission tomography/computed tomography allows correlation with the surgical procedure, therefore its standardization is advisable.

Salvage radiotherapy in prostate cancer patients. Planning, treatment response and prognosis using (11)C-choline PET/CT. / Radioterapia de rescate en pacientes con cáncer de próstata. Planificación, respuesta al tratamiento y pronóstico mediante PET/TC con (11)C-colina.

OBJECTIVE: To assess the prognostic value of the therapeutic response by (11)C-choline PET/CT in prostate cancer patients with biochemical recurrence in which (11)C-choline PET/CT indicated radio-guided radiotherapy. METHODS: The study included 37 patients initially treated with prostatectomy, who were treated due to biochemical recurrence. (11)C-choline PE/CT detected infra-diaphragmatic lymph-node involvement. All were selected for intensity modulated radiation therapy, escalating the dose according to the PET findings. One year after treatment patients underwent PSA and (11)C-choline PET/CT categorizing response (complete/partial/progression). Clinical/biochemical/image monitoring was performed until appearance of second relapse or 36 months in disease-free patients. RESULTS: (11)C-choline PET/CT could detect lymph nodes in all 37 patients. They were 18 (48.6%) of more than a centimetre in size and 19 (51.3%) with no pathological CT morphology: 9 (24.3%) with positive lymph nodes of around one centimetre and 10 (27.0%) only less than a centimetre in size. The response by (11)C-choline PET/CT was categorised one year after radiotherapy: 16 patients (43.2%) complete response; 15 (40.5%) partial response, and 6 (16.2%) progression. The response was concordant between the PSA result and (11)C-choline PET/CT in 32 patients (86.5%), and discordant in five (13.5%). New recurrence was detected in 12 patients (80%) with partial response, and 5 (31.2%) with complete response. The mean time to recurrence was 9 months after partial response, and 18 months after complete response (significant difference, p<.0001). CONCLUSION: (11)C-choline PET/CT allows the selection of patients with recurrent prostate cancer candidates for radiotherapy and to plan the technique. The evaluation of therapeutic response by (11)C-choline PET/CT has prognostic significance.

[Study of patients with prolonged fever with (18)F-FDG PET/CT]. / Estudio de pacientes con síndrome febril prolongado con 18F-FDG PET-TC.

OBJECTIVE: To review the findings on (18)F-FDG PET-CT in patients with fever of unknown origin lasting more than 7 days. MATERIAL AND METHODS: This retrospective descriptive observational study included 93 (18)F-FDG PET-CT studies to detect a fever-causing focus done at three nuclear medicine centers from October 2006 through February 2014. A nuclear medicine specialist and a radiologist reviewed the images for foci of pathological uptake; another specialist's opinion resolved discrepancies. The findings on (18)F-FDG PET-CT studies were checked against clinical and/or histological findings. RESULTS: Abnormal (18)F-FDG uptake on PET-CT that could explain the cause of the fever was found in 52 (56%) of the 93 studies, and the cause of the fever was confirmed in 50 of these 52 studies. In the 50 cases in which the cause of the fever was confirmed, infection was the most common cause (54%), followed by noninfectious inflammatory disease (28%) and tumors (18%). CONCLUSION: (18)F-FDG PET-CT is useful in diagnosing the cause of prolonged febrile illness, so it might be practical to use it earlier in the diagnostic process.

(11)C-choline PET/CT and multiparametric MRI in patients with biochemical relapse of prostate cancer.

CLINIC PROBLEM AND CASE SERIES: To assess the diagnostic usefulness of (11)C-choline PET/CT vs. multi-parametric MRI in the prostate cancer relapse. A retrospective study of 21 patients with prostate cancer treated initially with surgery (n=12), radiotherapy (n=9). PSA levels were increased (post-surgery: .3-3.6 ng/ml; post-radiotherapy: 2.4-8.8 ng/ml). In an interval of time of 15 days all patients were underwent to: whole-body-dual-modality PET-CT carried out early after (11)C-choline (296 ± 29 MBq) injection, and multiparametric prostate MRI with paramagnetic intravenous contrast (using anatomical imaging sequences, diffusion-weighted imaging and dynamic contrast-enhanced imaging). On the basis of our results, all patients were underwent to directed diagnosis and/or clinical, analytic and imaging follow-up. In 15 patients (71.4%) both procedures showed concordant results: 4 negative and 11 positive cases [7 local recurrences, 3 isolated pelvic lymph nodes (2 infracentimetric), 1 local relapse and only one M1 bone metastases]. The results were discordant in 6 patients (28.6%): 3 local relapses in MRI with no PET significance, 1 local relapse in PET with no MRI significance. 2 bone metastases were identified with PET (out of the field-of-view of MRI). COMMENT: (11)C-choline PET/CT and multi-parametric MRI play a complementary role in the detection of local relapse in prostate cancer patients, with similar sensitivity for the detection of lymph involvement. Whole-body 11C-choline PET/CT technique is also useful for bone staging.

Niemann-Pick type C disease: a novel NPC1 mutation segregating in a Greek island.

Niemann-Pick type C (NPC) disease is a rare autosomal recessive lysosomal storage disease, exhibiting an extremely heterogeneous clinical phenotype. It is a cellular lipid trafficking disorder characterized by the accumulation in the lysosomal/late endosomal system of a variety of lipids, especially unesterified cholesterol. So far two genes, NPC1 or NPC2, have been linked to the disorder. It is a panethnic disease for which two isolates have been described. We present a novel NPC1 mutation (p.A1132P; c.3394G>C) identified in homozygosity in two patients originating from the same small town of an Aegean Sea island and the results of the broad screening of their extended families. Overall 153 individuals have so far been investigated and a total of 64 carriers were identified. Moreover a common descent of the individuals tested was revealed and all carriers could be traced back to a common surname, apparently originating from a common ancestor couple six generations back. The mutation was found associated with an uncommon haplotype in the island that is also present in other populations.

[Personalized nursing care in hospital and its effects on the patient-nurse trust relationship]. / Personalización de cuidados hospitalarios y su efecto sobre la relación de confianza enfermera-paciente.

OBJETIVES: To determine the level of implementation of an inpatient personalized nursing care model in four hospitals of the Andalusian Health Service, and to determine if there is an association between this model and the perception of trust in the nurse by the patient. METHOD: An observational cross-sectional study included the patients discharged during a period of 12 months from hospital wards that used the Inpatient Personalized Nursing Care Model of the Andalusian Health Service (based on Primary Nursing Model). The level of implemention was evaluated using the Nursing Care Personalized Index (IPC), made by «patient report¼ methodology, and the nurse-patient trust relationship was evaluated at the same time as the IPC. Statistical analysis included descriptive data analysis, Chi-squared test, and bivariate and multivariate logistic regression, with and without stratifying by hospitals wards. RESULTS: A total of 817 patient were included. The implementation of the inpatient personalized nursing care model varied between 61 and 79%. The IPC values showed a strong association with the nurse-patient trust relationship, and that for each point increase in the IPC score, the probability of a nurse-patient trust relationship increased between 50 and 130% (0.120.58). CONCLUSION: The implementation of a personalized nursing care model in the wards studied was higher in the surgicals wards and at regular level in medical wards. Furthermore, the influence of the inpatient personalized nursing care model on the nurse-patient trust relationship has been demonstrated using the IPC model. This trust is the main component for the establishment of a therapeutic relationship.

Sequential extraction of polysaccharides from enzymatically hydrolyzed okara byproduct: physicochemical properties and in vitro fermentability.

Okara, a byproduct of soymilk production, has been upgraded through the use of an enzymatic treatment with Ultraflo L® to give a product (okara(ET)) which has a higher content of soluble dietary fibre and an enhanced ratio of soluble: insoluble fibre than is found in okara without treatment. Polysaccharides were isolated from okara(ET) by sequential extraction to yield soluble fractions in water (22%), CDTA (8.7%), alkali (37.7%) without and NaClO2 (9.1%) and the cellulosic residue represents a (22.5%). The physicochemical properties of okara(ET) were improved due to the enzymatic treatment: oil retention capacity (6.94g/g), water retention capacity (10.76g/g) and swelling capacity (13.85g/g) were higher than in okara that had not undergone enzymatic treatment. The gelation capacity (8%) and the cation exchange capacity (8.96mEq/kg) of okara(ET) were lower than that of other byproducts. Short chain fatty acid production during in vitro fermentation of okara(ET) by a pure culture of Bifidobacterium bifidus was mainly represented by acetic acid, followed by propionic and butyric acids. In addition, the decreases in pH and substrate consumption demonstrated the bifidogenic capacity of okara(ET).

[Personalized nursing care and perceived quality of care in hospitals]. / Personalización enfermera y calidad percibida del cuidado en el ámbito hospitalario.

OBJECTIVE: To determine whether there is an association between the Primary Nursing Model and perceived quality of care. METHOD: An observational, descriptive, cross-sectional study in four hospital wards with Primary Nursing organization. Over a 12-month period, all the patients discharged from each ward were included in this study. The degree of development of Primary Nursing was measured by using the Personalization of Nursing Care Index and the perceived quality of care was measured with the LOPSS-12. Bivariate statistical analysis was carried out through ANOVA and Student's t-tests. Multivariate linear regression analysis was then applied to correlated variables (p < 0.05). RESULTS: 817 patients were included, 447 from two medical wards and 370 from two surgical wards. After a preliminary data analysis performed 6 months after the start of the study, four items were removed from the LOPSS-12 and each of the remaining items were analyzed separately. Scores for both patient satisfaction and the introduction of the Primary Nursing Model were higher in the surgical wards. Bivariate and multivariate regression analyses showed a statistically significant (p < 0.05) association between implantation of the model and all except one of the items included in the questionnaire. CONCLUSIONS: The introduction of the Primary Nursing Model in hospital wards allows the presence of a primary nurse for each patient and consequently improves the nurse-patient relationship, increasing perceived quality of care among patients.

[Validity and reliability of the personalised nursing care index in a hospital medical unit]. / Validez y fiabilidad del índice de personalización de cuidados en una unidad médica hospitalaria.

OBJECTIVES: To determine the validity and reliability of the personalised nursing care index (PNCI). METHODS: A descriptive study was carried out in the Puerta del Mar Hospital (Cádiz) of the Andalusian Health Service, which included all patients admitted to an Internal Medicine ward from May 2007 to July 2008. A descriptive analysis was performed on the population included in the study. Furthermore, reliability was analysed with the 20-Kuder-Richardson coefficient and a correlation matrix between PNCI items; and validity via a maximum likelihood factorial analysis, and a ROC curve to determine sensitivity and specificity. RESULTS: A total of 219 people were included in the survey, of whom 74.4% were patients and 26.6% caregivers. The percentages of males and females were similar with a mean age of 62.5 years and 48.4% finished basic school education. The 20-Kuder-Richarson value was 0.835; and a positive correlation between items, which corresponded to 3 groups of items (factors). The maximum likelihood factorial analysis confirmed the 3 items-factor groups with a Promax rotation due to the high correlation between them. The maximum explained variance was 91.42%. The ROC curve area was 90.1% with a cut-off point of 8, for a sensitivity of 79.9% and a specificity of 90.6%. CONCLUSIONS: The PCNI is reliable, with the internal consistency coefficient value in between an optimum range. Furthermore, factors obtained from the matrix correlation inter-items were confirmed with a factorial analysis, resulting in a high explained variance. The curve ROC area is excellent compared to the gold standard, considered as the perception of confidence relationship.

Molecular characterization of five patients with homocystinuria due to severe methylenetetrahydrofolate reductase deficiency.

Methylenetetrahydrofolate reductase (MTHFR) plays a major role in folate metabolism. Disturbed function of the enzyme results in hyperhomocysteinemia and causes severe vascular and neurological disorders and developmental delay. Five patients suspected of having non-classical homocystinuria due to MTHFR deficiency were examined with respect to their symptoms, MTHFR enzyme activity and genotypes of the MTHFR gene. All patients presented symptoms of severe central nervous system disease. Two patients died, at the ages of 15 months and 14 years. One patient is currently 32 years old, and is being treated with betaine and folinic acid. The other two patients, with an early diagnosis and a severe course of the disease, are currently improving under treatment. MTHFR enzyme activity in the fibroblasts of four of the patients was practically undetectable. We found four novel mutations, three of which were missense changes c.664G> T (p.V218L), c.1316T> C (p.F435S) and c.1733T> G (p.V574G), and the fourth was the 1-bp deletion c.1780delC (p.L590CfsX72). We also found the previously reported nonsense mutation c.1420G> T (p.E470X). All the patients were homozygous. Molecular modelling of the double mutant allele (p.V218L; p.A222V) revealed that affinity for FAD was not affected in this mutant. For the p.E470X mutation, the evidence pointed to nonsense-mediated mRNA decay. In general, genotype-phenotype analysis predicts milder outcomes for patients with missense changes than for those in which mutations led to severe alterations of the MTHFR protein.

Synthesis of lidocaine-loaded PLGA microparticles by flow focusing. Effects on drug loading and release properties.

In the present work, two methods for the preparation of lidocaine-loaded PLGA microparticles are compared. The differences between the polymeric particles obtained by solvent evaporation (SEVM) or flow focusing (FF) were studied by means of scanning electron microscopy and surface thermodynamics determinations. A detailed investigation of the capabilities of the polymer particles to load this drug is described. The physical state of the drug in the polymeric particles and the existence of interactions between both entities were studied by differential scanning calorimetry. The main factors determining the lidocaine incorporation and the release kinetics were the synthesis procedure followed, the amount of drug dissolved in the organic phase during the synthesis routine, the type of polymer (molecular weight and end chemical groups) and the size and the hydrophobic/hydrophilic properties of the particles. The FF technology allowed higher drug incorporations and slower release kinetics. The release studies showed a biphasic profile probably due to diffusion-cum-degradation mediated processes.

Targeting the Bacillus subtilis genome: an efficient and clean method for gene disruption.

A method to disrupt multiple Bacillus subtilis genes is described. A resistance cassette is used to interrupt an amplified target sequence from the B. subtilis chromosome. The cassette is composed of a gene conferring resistance to chloramphenicol (Cm) or spectinomycin (Sp) flanked by two directly oriented beta cognate sites (six site) (SCS or SSS, respectively). The linearized construct is used to transform B. subtilis competent cells with selection for Cm or Sp resistance. Transformants with the desired gene disrupted by the SCS or SSS cassette, integrated by a double cross-over event, were confirmed by PCR analysis. A segregationally unstable plasmid-borne beta site-specific recombinase is transferred into the background. Protein beta catalyzes excision of the intervening sequence between the two six sites leading to a target gene disrupted only by a six site. This site has an internal promoter capable of reading downstream genes. To generate multiple disruptions, the cycle can be repeated many times provided that two six sites are separated by about a 70-kb interval.

Bacillus subtilis RecG branch migration translocase is required for DNA repair and chromosomal segregation.

The absence of Bacillus subtilis RecG branch migration translocase causes a defect in cell proliferation, renders cells very sensitive to DNA-damaging agents and increases approximately 150-fold the amount of non-partitioned chromosomes. Inactivation of recF, addA, recH, recV or recU increases both the sensitivity to DNA-damaging agents and the chromosomal segregation defect of recG mutants. Deletion of recS or recN gene partially suppresses cell proliferation, DNA repair and segregation defects of DeltarecG cells, whereas deletion of recA only partially suppresses the segregation defect of DeltarecG cells. Deletion of recG and ripX render cells with very poor viability, extremely sensitive to DNA-damaging agents, and with a drastic segregation defect. After exposure to mitomycin C recG or ripX cells show a drastic defect in chromosome partitioning (approximately 40% of the cells), and this defect is even larger (approximately 60% of the cells) in recG ripX cells. Taken together, these data indicate that: (i) RecG defines a new epistatic group (eta), (ii) RecG is required for proper chromosomal segregation even in the presence of other proteins that process and resolve Holliday junctions, and (iii) different avenues could process Holliday junctions.

Comparison of immunoradiometric assays for determination of thyroglobulin: a validation study.

In this study we compared and validated commercial immunoradiometric assays (IRMA) to determine thyroglobulin (Tg) levels in serum. From a set of 440 samples, 68 were selected to calculate the validation parameters and the clinical performance of the assays. The commercial kits evaluated were the Tg-CTK (DiaSorin), IRMAZenco Tg (ZenTech), and SELco-Tg (Medipan). We found that 21% of the collected samples were in the critical range of concentration. Detection limits were calculated as being below 3 microg/L. Intra- and inter-reproducibility were lower than 3.1% and 9.2%, respectively. Dilution and recovery studies provided quantitative determinations. Correlation regression coefficients from the results of the methods were obtained. The determined concentrations were compared with the clinical evidence of disease. Variation in the 125-iodine-labeled antibody concentration and control charts showed the robustness of the methods. Analysis time and the simplicity of the methods were also evaluated. Reliable Tg determination is important for monitoring patients with differentiated thyroid cancer (DTC), controlling other thyroid diseases, and assessing the quality of imaging techniques. A strategy for verification and comparison based on analytical parameters and clinical performance is proposed.