PDGF-BB regulates splitting angiogenesis in skeletal muscle by limiting VEGF-induced endothelial proliferation.

VEGF induces normal or aberrant angiogenesis depending on its dose in the microenvironment around each producing cell in vivo. This transition depends on the balance between VEGF-induced endothelial stimulation and PDGF-BB-mediated pericyte recruitment, and co-expression of PDGF-BB normalizes aberrant angiogenesis despite high VEGF doses. We recently found that VEGF over-expression induces angiogenesis in skeletal muscle through an initial circumferential vascular enlargement followed by longitudinal splitting, rather than sprouting. Here we investigated the cellular mechanism by which PDGF-BB co-expression normalizes VEGF-induced aberrant angiogenesis. Monoclonal populations of transduced myoblasts, expressing similarly high levels of VEGF alone or with PDGF-BB, were implanted in mouse skeletal muscles. PDGF-BB co-expression did not promote sprouting and angiogenesis that occurred through vascular enlargement and splitting. However, enlargements were significantly smaller in diameter, due to a significant reduction in endothelial proliferation, and retained pericytes, which were otherwise lost with high VEGF alone. A time-course of histological analyses and repetitive intravital imaging showed that PDGF-BB co-expression anticipated the initiation of vascular enlargement and markedly accelerated the splitting process. Interestingly, quantification during in vivo imaging suggested that a global reduction in shear stress favored the initiation of transluminal pillar formation during VEGF-induced splitting angiogenesis. Quantification of target gene expression showed that VEGF-R2 signaling output was significantly reduced by PDGF-BB co-expression compared to VEGF alone. In conclusion, PDGF-BB co-expression prevents VEGF-induced aberrant angiogenesis by modulating VEGF-R2 signaling and endothelial proliferation, thereby limiting the degree of circumferential enlargement and enabling efficient completion of vascular splitting into normal capillary networks despite high VEGF doses.

Fusarium riograndense sp. nov., a new species in the Fusarium solani species complex causing fungal rhinosinusitis.

Invasive fusariosis has a high mortality and is predominantly observed in patients with leukemia. We report the first case of a novel species of Fusarium, Fusarium riograndense sp. nov, isolated from a lesion in the nasal cavity lesion of a patient with acute lymphoblastic leukemia. The etiological agent was identified by Multilocus Sequencing Typing (MLST), including RPB2, TEF-1α, and ITS-LSU sequences, the gold standard technique to identify new species of Fusarium. MLST and phenotypic data strongly supported its inclusion in the F. solani species complex (FSSC). The new species produced a red pigment in the Sabouraud Dextrose Agar similar to other members of the complex. The macroconiodia developed from phialides on multibranched conidiophores which merge to form effuse sporodochia with a basal foot-cell instead of papilla in basal cell shape. The microconidia were ellipsoidal, 0-1-septated, produced from long monophialides. Chlamydospores were produced singly or in pairs. Amphotericin B (MIC 1µg/mL) was the most active drug, followed by voriconazole (MIC 8µg/mL). The patient was successfully treated with voriconazole. Our findings indicate another lineage within FSSC capable causing of invasive human infection.

Bone marrow bi-hypoplasia in a dog with a sertoli cell tumor / Hipoplasia dupla de medula óssea em um cão com tumor de células de sertoli

A 20-year-old unneutered male poodle presented prostration, apathy, staggering gait, lack of appetite and tick infestation. The dog was diagnosed with a Sertoli cell tumor in an undescended testicle by cytological, histopathological and immunohistochemical tests. Pancytopenia with moderate nonregenerative anemia, leukopenia and severe thrombocytopenia were detected in the complete blood count. Cytological and histopathological evaluation of the bone marrow revealed a cellularity of 30%, with erythroid (59%), lymphoid (40%) and mast cells (1%), and an absence of granulocytic, monocytic and megakaryocytic lineage cells. In post-mortem examinations, changes related to hemostatic disorders were found. The absence of microorganisms in molecular tests and an estrogen serum concentration over reference values confirmed hyperestrogenism as a possible cause of pancytopenia. The literature describes a Sertoli cell tumor hyperestrogenism that induced pancytopenia, along with bone marrow hypoplasia of all hematopoietic lineages. In contrast, in the present case, the erythroid precursor cells were preserved in the bone marrow, although there were no reticulocytes circulating in the blood. This case, therefore, should be considered in future investigations of pancytopenia induced by Sertoli cell tumor hyperestrogenism.(AU)

Um cão Poodle, macho, de 20 anos, não castrado, apresentou prostração, apatia, andar cambaleante, falta de apetite e infestação por carrapatos. Nesse animal, foi diagnosticado tumor de células de Sertoli em um testículo não descendente, utilizando-se citologia, histopatologia e imuno-histoquímica. Pancitopenia com anemia moderada não regenerativa, leucopenia e trombocitopenia intensas foram detectadas no hemograma. Na avaliação citológica e histopatológica da medula óssea, havia celularidade de 30%, constituída pelas linhagens eritroide (59%) e linfoide (40%) e por mastócitos (1%), com ausência de células das linhagens granulocítica, monocítica e megacariocítica. Em exames post mortem, mudanças relacionadas à hemostasia foram encontradas. A ausência de micro-organismos nos testes moleculares e a concentração sérica de estrogênio acima dos valores de referência confirmaram hiperestrogenismo como a possível causa da pancitopenia. A literatura descreve hiperestrogenismo em tumores de células de Sertoli induzindo pancitopenia associada com hipoplasia da medula óssea de todas as linhagens hematopoiéticas. Em contraste, no presente caso, as células precursoras eritróides estavam preservadas na medula óssea, embora não houvesse reticulócitos no sangue. Assim, o relato apresentado deve ser considerado em futuras investigações de pancitopenia induzida por hiperestrogenismo em tumor de células de Sertoli.(AU)

Avaliação hemogasométrica em cadelas com piometra / Hemogasometric evaluation in bitches with pyometra

A piometra é uma afecção comum em cadelas com uma etiologia hormonal associada à infecção bacteriana, levando ao acúmulo de exsudato uterino. Desequilíbrios ácido-base e hidroeletrolíticos são complicações que contribuem para a progressão da doença, o que piora o estado geral da paciente e pode levá-la ao óbito. O objetivo do presente trabalho foi caracterizar os distúrbios ácido-base e eletrolíticos em cadelas com piometra, além de avaliar se a terapia hídrica pré-cirúrgica (Ringer lactato) é efetiva na correção desses desequilíbrios. Vinte cadelas com piometra foram submetidas à hemogasometria em oito tempos preestabelecidos. Concluiu-se que o distúrbio ácido-base mais frequente foi a alcalose respiratória e que a terapia hídrica no pré-cirúrgico com solução Ringer lactato foi efetiva na correção da acidose metabólica e proporcionou melhora na alcalose respiratória, embora não tenha corrigido quadros de alcalose metabólica.

Pyometra is a common disease in dogs with a hormonal etiology associated with a bacterial infection and leading to accumulation of uterine exudates. Acid-base and electrolyte disturbances are complications that contribute to disease progression, worsening the condition of the patient, possibly leading death. The aim of this study was to characterize the acid-base and electrolyte disturbances in dogs with pyometra, and to evaluate whether preoperative fluid therapy (Ringer's lactate) is effective in correcting these imbalances. Twenty bitches with pyometra were subjected to blood gas analysis in eight pre-set times. It was concluded that the acid-base disorder was the most frequent respiratory alkalosis and fluid therapy in the preoperative Ringer 's lactate solution was effective in the correction of metabolic acidosis, although this has not corrected metabolic alkalosis frames and has provided improved alkalosis breathing .

The association between retinal microvascular changes, metabolic risk factors, and liver histology in pediatric patients with non-alcoholic fatty liver disease (NAFLD).

BACKGROUND: The prevalence of childhood obesity is increasing worldwide. Studies in adult populations show that retinal microvascular changes are associated with obesity and components of the metabolic syndrome. In our study we have assessed the effect of body mass index (BMI), metabolic parameters, and adiposity on the retinal microvasculature in children. METHODS: Fifty-four consecutive children with biopsy-proven NAFLD were enrolled in this study. Anthropometric and laboratory parameters were obtained using standardized protocols. Retinal caliber was quantified from digital retinal images using well-known computer-based programs. Twenty-four-hour ambulatory blood pressure monitoring was measured using a standard protocol. RESULTS: In our population, the prevalence of retinopathy was of 53 % (13 males). The 29 patients with retinopathy (mean age 10.91 ± 3.10) showed significantly higher values of triglycerides (mg/day) (105.57 vs. 90.20, p = 0.04), basal insulin (mUI/ml) (17.20 vs. 12.97, p = 0.02), and HOMA-IR (3.37 vs. 2.76, p = 0.04). The patients with a HOMA-IR >2.5 (OR = 3.34, p = 0.02; 95 % IC, 1.07-10.39), and systolic non-dipping (OR 4.16, p = 0.028, 95 % IC, 1.11-13.67), have an increased risk of retinopathy. Moreover, the study of correlation between all stages of liver biopsy (CRN criteria) and the grade of retinopathy showed a positive correlation with fibrosis (r = 0.31) and an NAS score (r = 0.28). CONCLUSIONS: We found an association between metabolic parameters and nocturnal blood pressure on the retinal microvasculature among the obese children with NAFLD. Furthermore, for the first time, we report the positive relationship between hepatic fibrosis in pediatric NAFLD patients and the degree of retinopathy signs.

Gasless fetoscopy: a new approach to endoscopic closure of a lumbar skin defect in fetal sheep.

OBJECTIVE: To develop a new endoscopic approach to the correction of a myelomeningocele-like defect in fetal sheep. METHODS: The fetuses of 9 pregnant ewes, with an average gestational age of 115 days, were subjected to a 3.0 x 2.0 cm removal of the skin over the lumbar spine, performed through hysterotomy. The uterus was closed, and three 5-mm endoscopic cannulas, without valve mechanisms, were inserted. In the pilot phase (2 animals), we initially worked exclusively in the amniotic fluid space. In the study phase, we partially withdrew the fetus from the amniotic fluid to completely expose its back. By simply allowing air to enter the amniotic cavity (without gas injection), a working space was created using a uterine lift device. The skin around the defect was dissected, and a biosynthetic cellulose material was applied to cover the area. A continuous suture of the skin was performed to completely hide the material. RESULTS: The combined air/fluid space allowed the skin to be successfully closed in 6 out of 7 cases in the study phase. All fetuses were alive at the end of the procedures. Time to complete the endoscopic part of the procedure fell from 3 to 1 h by the end of this series. Premature birth occurred in 2 of the 4 cases allowed to continue with the pregnancy. CONCLUSION: A new gasless fetoscopic surgery technique was developed as an alternative to current techniques used for fetal endoscopic surgery.

Long-term sequelae after 1,311 primary inguinal hernia repairs.

BACKGROUND: Aim of this study was to analyze long-term sequelae, risk factors, and satisfaction after inguinal hernia primary repair. METHODS: A postal questionnaire was mailed to all patients operated between January 1997 and December 2004 for inguinal hernia repair. Patients who had a lump in the groin and patients who experienced chronic problems were invited for a physical examination. Patients who reported having chronic pain were asked to fill out the short-form McGill Pain Questionnaire (SF-MPQ). RESULTS: Chronic pain was present in 18.1% of cases. The strongest risk factors were presence of recurrence, use of heavyweight mesh, and age younger than 66 years. By means of the SF-MPQ, we found that the pain reported by most patients was sensory-discriminative in quality, with "tender" and "aching" being the most common descriptors used. About 71.3% of replies used descriptors typical of nociceptive pain, 8.9% of neuropathic pain, and 19.8% of nociceptive plus neuropathic. Chronic pain was severe in 2.1% of patients and interfered with normal activities, work, and exercise. The cumulative recurrence rate was 2.1%. There was a strong correlation between lump and recurrence. Patients declared themselves satisfied with the result of the operation in 93.1% of cases. Due to chronic pain, 6.5% of patients were unsatisfied. CONCLUSIONS: This study demonstrates that the main problem after inguinal hernia repair remains chronic pain, which was the primary reason of dissatisfaction. The SF-MPQ is feasible and easy to administer to all patients and provides important information about qualitative features of the pain.

Effects of coffees before and after special treatment procedure on cell membrane potentials in stomach cells.

Coffee, one of the most excessively used beverages worldwide, commences the risk of gastroesophageal reflux (GER), which may lead to gastric ulcers and increase the risk of gastric cancer. Many attempts have been made by the coffee industry to diminish the irritating effect on mucosa by means of altering the extraction methods concerning gerbic acids and the roasting processes. This paper describes the effect of differently produced coffees involving two brands of Darboven and two brands of other coffee roasters. The aim of this study was to prove the results of gastric potential measurements we found in literature by using human AGS gastric epithelial cells (human adenocarcinoma). All four coffee extracts tested differentially affected the membrane resting potential of AGS cells. Coffees no. 1 and no. 2 depolarized the cells, presumably by increasing the cation entry into the cytosol. In marked contrast, coffee no. 4 hyperpolarizes the cells, possibly by H(+) extrusion and/or Cl(-) influx, suggesting that this coffee might increase acidity in the stomach, which might negatively affect the stomach, especially in people with gastroesophageal reflux symptoms. Overall, our data suggest that different roasting methods of coffees affect the membrane potentials of AGS stomach cells, resulting in increased influx of H+ possibly resulting in decreased stomach acidity and thus reducing GER. These results are in good accordance with clinical pharmacological results from potential difference measurements in healthy volunteers we found in the literature.

Mortality in a cohort of pesticide applicators in an urban setting: sixty years of follow-up.

The study is a further follow-up of a cohort of 168 urban pesticide applicators of the municipality of Rome who were first employed in 1946. An earlier analysis of the mortality of this group concerned the deaths observed up to 1987, and showed a significant excess in mortality from liver cancer. In this report we present an updated follow up of the mortality of the cohort, which comprises the total of 85 deaths for the entire period of observation, corresponding to 5227 person/years. The living status of each member of the cohort was ascertained through the official records up to 2005. For the 85 deceased individuals, the primary cause of death was coded according to the 9th Revision of the ICD. Standardized mortality ratios (SMR) were calculated on the basis of the age, sex, and cause specific mortality rates prevailing during the same calendar years in the province of Rome. The SMR from all causes for the whole cohort was 103.8 (90 %CI 86 124). The SMR for all cancers was 106.0 ( 90 % CI 75-146). An increased risk was observed for the exposed for cancer of the gallbladder (SMR 723.8 90% CI 129-2279), of the liver (SMR 596.3, 90 % CI 204-1365) and for cancer of the nervous system (SMR 529.2, 90 % CI 144-1368). All increases were statistically significant, but no association was found between the increased risk of these cancers and the longer duration of exposure. The increase in risk of the three cancers mentioned above (liver, nervous system and gallbladder), was further increased, when the analysis was restricted to the workers exposed prior to the 1978 ban of DDT and products containing arsenic.

TNF increases camptothecin-induced apoptosis by inhibition of NF-kappaB.

rHuTNF potentiates CPT-cytotoxicity in human ovarian A2780 cells. In this study, we examined the role of NF-kappaB in this potentiation. A pulse-labelled DNA study indicated that the combination CPT+TNF had little effect on the rate of DNA elongation at 6 h after drug removal, whereas CPT alone produced a complete inhibition for at least 6 h after drug removal. Flow cytometry analyses showed that CPT+TNF arrested cells in the G2-M phase, whereas CPT blocked cells in S phase. Looking at the persistence of the NF-kappaB complexes in cells, it appeared that they were still present at 24 h in TNF-treated cells. In contrast, in CPT-treated cells they persisted for 6 h. In CPT+TNF-treated cells, the NF-kappaB complexes disappeared quickly and became undetectable at 6 h. The induction of apoptosis was detected only in the CPT+TNF treated cells (using flow cytometry, a filter binding assay and ApopTag staining). These findings show that TNF, in combination with CPT, reduces the time that NF-kappaB complexes persist in cells likely resulting in the induction of apoptosis.

Estudo comparativo da cicatrizaçäo de enterorrafias em planos aposicional e invaginante no cólon descendente de eqüinos / Comparative study between appositional and inverting pattern for closure of descending colon enterotomies in equines

O estudo foi conduzido com o objetivo de comparar o processo cicatricial do cólon descendente de eqüinos, quando submetido a duas técnicas de sutura, uma em plano aposicional e outra em dois planos com invaginaçäo. Foram utilizados 15 eqüinos sadios e a intervençäo cirúrgica foi realizada com os animais em decúbito lateral direito, sob anestesia geral inalatória. O acesso à cavidade abdominal foi feito pelo flanco esquerdo, e após exteriorizaçäo do cólon descendente, realizaram-se duas enterotomias de 5cm de extensäo cada, distanciadas 20cm uma da outra. Os animais foram aleatoriamente distribuídos em cinco grupos de três animais cada e sacrificados aos 3, 7, 14, 21 e 35 dias pós-operatório. O exame necroscópico revelou a presença de aderências nos dois padröes de sutura. Em nove eqüinos foram observadas aderências no padräo de sutura aposicional (60,0 por cento +/- 12,6) e em quatro no padräo com invaginaçäo (26,6 por cento +/- 11,4). Näo foi verificada interferência com o trânsito intestinal em nenhum paciente. O exame histopatológico revelou regeneraçäo da camada mucosa a partir do sétimo dia de pós-operatório em ambos os tipos de satura. O fio de poliglactina 910 empregado nas enterorrafias do cólon descendente se mostrou resistente, de fácil manuseio e com boa capacidade para manter os nós aplicados, causando moderada reaçäo inflamatória do tipo granulomatosa

Vulvar keratinizing squamous cell carcinoma in a 26-year-old woman.

A 26-year-old Hispanic woman complaining of "itching" and "herpetic lesions" on the vulva for 9 months was seen at a university hospital. On physical examination, multiple vulvar masses were noted. Biopsies taken from these lesions showed invasive keratinizing squamous cell carcinoma. The vulvectomy specimen revealed 4 tumor masses, the largest located on the mons pubis. Although the incidence of vulvar intraepithelial neoplasia has increased in recent years, only very few cases of invasive carcinoma have been reported in young women. The tumors that occur at a younger age characteristically have basaloid or warty histology, in contrast to those occurring in older women, which usually are well-differentiated keratinizing carcinomas. We believe this is an unusual case of vulvar squamous cell carcinoma. In addition to our patient's young age, her tumor had a histologic profile usually found in lesions of an elderly woman. The tumor was negative for human papillomavirus by polymerase chain reaction analysis and was positive for p53 by immunohistochemistry.

A retro-inverso peptide homologous to helix 1 of c-Myc is a potent and specific inhibitor of proliferation in different cellular systems.

In 1998 we reported that an L-peptide derived from H1 of c-Myc (Int-H1-S6A,F8A), linked to an internalization sequence from the third a-helix of Antennapedia, was endowed with an antiproliferative and proapoptotic activity toward a human mammary cancer cell line: The activity apparently depends upon the presence of the Myc motif. In the present work we have added new dimensions to our original findings. It is known that short retro-inverso (RI-) peptides can assume a 3D conformation very close to their corresponding L-forms and can be recognized by the same monoclonal antibody. We synthesized a RI-peptide form of our original L-peptide: It was much more resistant to serum peptidases than the original molecule (a half life of days rather than hours); in addition, the RI-form of the original Antennapedia internalization sequence was perfectly capable of carrying a D-peptide into human cells. We have studied three different potentially active peptides. L-peptides: Int-H1wt, Int-H1-S6A,F8A. D-peptides: RI-Int -H1-S6A,F8A. We have also studied three presumed control peptides: Int and RI-Int (no H1 motif), H1-S6A,F8A (no internalization sequence). Both 'active' and 'control' peptides have essentially confirmed our expectations, however, in cells treated with the higher concentration (10 mM) of the control peptide RI-Int, non-Myc related side effects could be detected. In order to investigate whether the antiproliferative activities displayed by some of our molecules were indeed related to an interference with the role of c-Myc (and molecules of the family), we chose an iso-amphipathic modified peptide of the H1 motif, with a proximity coefficient >50% and where the major change was at position 7 (F-->A). From a family of 73 H1 motifs belonging to (H1-Loop-H2) hu man sequences, the smallest evolutionary distance from our reference peptide was observed for the H1 of N-Myc, L-Myc, c-Myc, H1-S6A,F8A of c-Myc, and Max, in that order. Our reference peptide was therefore appropriate as a check of whether we were indeed observing activities related to Myc functions. Both Int-H1isoamph and the corresponding RI-Int-H1isoamph peptide were synthesized and studied. In terms of biological targets, we added to the human mammary cancer line of our previous work (MCF-7 cells) a colon cancer line (HCT-116 cells) and also a system of normal cells: human peripheral blood lymphocytes (PBLs) stimulated with phytohemoagglutinin (PHA). Peptides carrying an iso-amphipathic-modified H1 sequence were always very clearly (3-10 times) less active than the corresponding peptides carrying a conserved "H1 of Myc" motif. This finding was noted in five independent situations (all the cellular models considered at the present time): MCF-7 cells treated with L-peptides; MCF-7 cells treated with RI-peptides; HCT-116 cells treated with L-peptides; PBLs treated with L-peptides; PBLs treated with RI-peptides. Modulation of transcription levels of ornithine decarboxylase (ODC), p53, and glyceraldehyde-3-phosphate dehydrogenase (GAPDH), in PBLs treated with our different molecules, was well compatible with an interference by our active peptides at the level of Myc transcriptional activity. We had already reported a similar observation in MCF-7 cells. On a molar basis, RI-peptides were about 5-10 times more potent and 30-35 times more stable in complete culture medium, than their corresponding L-forms. RI-Int can probably internalize longer peptido-mimetic molecules (for instance molecules mimetic of (H1-Loop-H2), or even more. These possibilities open the way to rodent studies and to more potent/selective Myc inhibitors-two steps closer to a potential drug.

Primary papillary serous carcinoma of the peritoneum: CT-pathologic correlation.

We present the CT findings of three cases of primary papillary serous carcinoma of the peritoneum. All patients presented with massive ascites. CT of the abdomen and pelvis showed omental caking in all patients. The parietal peritoneum of the pelvis showed diffuse enhancement with nodular thickening in all patients. No calcification was noted in the omental and parietal peritoneal masses, although psammoma bodies were present microscopically in one case. The ovaries were normal in size but showed a fine enhancing surface nodularity similar to the pelvic peritoneum. The CT findings of primary papillary serous carcinoma of the peritoneum are nonspecific, but this diagnosis should be considered when peritoneal carcinomatosis is seen on CT with normal-sized ovaries in the absence of other primary malignant neoplasms.

VEGF, flt-1, and KDR/flk-1 as prognostic indicators in endometrial carcinoma.

OBJECTIVE: Tumor angiogenesis is a highly regulated process under the influence of the host microenvironment and mediators. Studies of breast cancer and, more recently, ovarian and cervical cancer, demonstrate that neovascularization correlates with the likelihood of metastasis and recurrence. Vascular endothelial growth factor (VEGF), an important regulator of tumor angiogenesis in the endometrium, flt-1, and KDR/flk-1 are good markers of vascular proliferation. Being that angiogenesis is a precursor to the development of progressive disease, we hypothesize that quantifying VEGF, flt-1, and KDR/flk-1 expression in uterine malignancies is a superior predictor of metastatic potential and survival than is FIGO grade of tumor, depth of invasion, and histology. METHODS: The histologic slides of 47 patients with uterine malignancies (35 adenocarcinomas, 6 papillary serous, and 6 carcinosarcomas) were reviewed. The paraffin blocks from the primary tumor were obtained. Immunohistochemistry staining was performed for VEGF, flt-1, and KDR/flk-1. Microvessel density, used to analyze VEGF and receptor concentrations, was determined by two independent investigators, who were blinded to the patients clinical status. The impact of VEGF, flt-1, and KDR/flk-1 as well as stage, grade, depth of invasion, and nodal status on the incidence of metastases, recurrence, and survival was determined using logistic regression analysis and product limit life system survival analysis, respectively. RESULTS: Results indicated that when evaluating all three histologic types, only stage and grade of tumor were found to impact upon the incidence of recurrence and survival. When patients with carcinosarcoma and papillary serous adenocarcinoma were excluded from the analysis, once again only stage and grade of tumor were significant prognostic indicators of recurrence and survival. Only grade of tumor and depth of uterine invasion were significant predictors of a tumor's metastatic potential. VEGF, flt-1, and KDR/flk-1 proved to be of little significance in predicting metastases, recurrence, and survival. Patients with advanced disease in all three histologic subtypes often had low VEGF and receptor positivity. CONCLUSIONS: In this study, VEGF, flt-1, and KDR/flk-1 receptor concentrations did not correlate with the incidence of metastases, recurrence, and survival.

Avaliaçäo de fatores relacionados à transmissäo de infecçöes pelos Estreptococos do Grupo Mutans / Evaluation of factors related to the transmission of infections by the Mutans Streptococci

O objetivo deste estudo foi determinar os fatores relacionados à transmissäo de infecçöes pelos Estreptococos do Grupo Mutans (EM), dentre eles, quais as pessoas que estäo em maior contato com crianças na idade de dois a seis anos e qual é a correlaçäo dos níveis em EM existentes na saliva das crianças e seus responsáveis. Os resultados evidenciaram que säo as mäes as pessoas que ficam mais tempo com suas crianças e que existe uma similaridade bastante alta (73 por cento) entre os níveis de EM na saliva dos responsáveis e na saliva das respectivas crianças

Neural-network-assisted analysis and microscopic rescreening in presumed negative cervical cytologic smears. A comparison.

OBJECTIVE: To compare cytologists' detection of abnormalities when using neural network-assisted (NNA) review, as employed by the PAPNET Testing System and to compare the effectiveness of this mode of review to that of unassisted, conventional rescreening of cervical smears initially diagnosed as negative. STUDY DESIGN: The study was undertaken as part of a multicenter clinical trial involving over 10,000 smears from 10 investigation sites (9 academic institutions and 1 private laboratory). Using a subset of "negative" control smears from three university laboratories, the false negative detection yields of NNA review (performed using the PAPNET System) and conventional microscopic rescreening (performed as part of routine quality control practice) were compared. The false negative detection yield was defined as the percentage of rescreened negatives reclassified as abnormal. RESULTS: The results demonstrate that using NNA review, the detection yield of false negative smears, as a proportion of negative smears reexamined, is statistically significantly greater than that obtained using conventional quality control rescreening. The false negative yield generated using NNA analysis was 6.2% (142/2293) versus 0.6% (82/13761) for conventional rescreening. A statistically significant improvement in identification of abnormality is observed for NNA review as opposed to unassisted rescreening despite constraining the comparison in the following ways: (1) comparing the yields of rescreening of negative smears obtained from the same time intervals for both methods, (2) comparing the yields of rescreening of negative smears obtained from the years after the Clinical Laboratory Improvement Act (1990 and 1991) for both methods, and (3) disregarding the identification of atypical squamous cells of undetermined significance/atypical glandular cells of undetermined significance cases and comparing only the identification of squamous intraepithelial lesions using the two methods. CONCLUSION: Using neural network-assisted review, cytologists uncovered a significantly higher proportion of previously undetected cervical abnormalities per smear reexamined than they did using unassisted, conventional rescreening.

TIMP-2 over-expression reduces invasion and angiogenesis and protects B16F10 melanoma cells from apoptosis.

The matrix metalloproteinase (MMP) inhibitor TIMP-2 has a high specificity for gelatinase A/MMP-2. An imbalance between gelatinase A and TIMP-2 in favor of enzymatic activity is linked to the degradation of the extracellular matrix (ECM) associated with several physiologic and pathologic events, including angiogenesis, invasion and metastasis. Since TIMPs are secreted molecules, they have the potential to be used for gene therapy of certain tumors. We transfected B16F10 murine melanoma cells, a highly invasive and metastatic cell line, with an expression vector harboring a cDNA encoding for human TIMP-2. The clones obtained were isolated and examined for TIMP-2 over-expression and changes in tumor cell phenotype. The amount of recombinant TIMP-2 produced correlated with a reduction in invasion. In an in vivo angiogenesis assay, TIMP-2-transfected clones showed reduced levels of blood vessel formation, and in vitro conditioned media from TIMP-2 transfectants showed diminished induction of endothelial cell migration and invasion. TIMP-2 over-expression limited tumor growth in vivo and neoangiogenesis when cells were injected subcutaneously in mice in the presence of Matrigel. However, TIMP-2 overexpressing clones were found to be more resistant to apoptosis than parental and control melanoma cells, while necrosis was increased. Our data confirm the role of TIMP-2 in the down-regulation of metastasis and angiogenesis but indicate a possible involvement in tumor cell survival.

Cytologic changes in cervical smears associated with prolonged use of depot-medroxyprogesterone acetate.

BACKGROUND: Hormonal effects have always played a significant role in gynecologic cytology. In atrophic and postpartum smears, interpretation may be complicated by large numbers of parabasal cells with high nuclear cytoplasmic ratios and hyperchromatic nuclei that mimic precancerous lesions (squamous intraepithelial lesions, SILs). The authors have observed atrophic and postpartumlike changes in patients receiving depot-medroxyprogesterone acetate for prolonged periods. These alterations may lead to diagnostic uncertainty or falsely suggest the presence of SIL. METHODS: To evaluate the effect of chronic hormone use, smears from 29 depot-medroxyprogesterone acetate users (average age, 35.9 years) who had been amenorrheic for 5-72 months (average, 22.6 months) were identified. This group was matched with 25 nonusers (average age, 31.9 years). Maturation values (MVs) were calculated for both groups and cellular findings were evaluated. RESULTS: The user group had a significantly lower MV (38.45 vs. 64.60, P < 0.001). Among users, 6 of 29 smears (21%) were abnormal. One low grade SIL was biopsy-confirmed, but two high grade SILs and three smears of ASCUS had a negative Papanicolaou (Pap) smear and/or biopsy follow-up. Among nonusers, 4 of 25 smears (16%) were abnormal. Two patients with high grade SIL smears had positive biopsy or Pap smear follow-up, one with an ASCUS smear had a negative Pap smear follow-up, and one with a low grade SIL was lost to follow-up. CONCLUSIONS: The immature cellular pattern seen in smears from long term depot-medroxyprogesterone acetate users led to difficulty in determining the diagnosis in some cases. ASCUS cases among users were associated with high nuclear cytoplasmic ratios and hyperchromasia in parabasal metaplasialike cells. Biopsies in these cases showed epithelial atrophy, which was often associated with acute inflammation. In view of the fact that long term depot-medroxyprogesterone acetate administration may induce changes that mimic high grade SIL in a population already at high risk for SIL, there may be problematic cases in which diagnostic uncertainty is inevitable.

Significant reduction in the rate of false-negative cervical smears with neural network-based technology (PAPNET Testing System).

False-negative cervical Pap smears may lead to disability or death from carcinoma of the uterine cervix. New computer technology has led to the development of an interactive, neural network-based vision instrument to increase the accuracy of cervical smear screening. The instrument belongs to a new class of medical devices designed to provide computer-aided diagnosis (CADx). To test the instrument's performance, 487 archival negative smears (index smears) from 228 women with biopsy-documented high-grade precancerous lesions or invasive cervical carcinoma (index women) were retrieved from the files of 10 participating laboratories that were using federally mandated quality assurance procedures. Samples of sequential negative smears (total 9,666) were retrieved as controls. The instrument was used to identify evidence of missed cytological abnormalities, including atypical squamous or glandular cells of undetermined significance (ASCUS, AGUS), low-grade or high-grade squamous intraepithelial lesions (LSIL, HSIL) and carcinoma. Using the instrument, 98 false-negative index smears were identified in 72 of the 228 index women (31.6%, 95% confidence interval [CI]: 25% to 38%). Disregarding the debatable categories of ASCUS or AGUS, there were 44 women whose false-negative smears disclosed squamous intraepithelial lesions (SIL) or carcinoma (19.3%; 95% CI: 14.2% to 24.4%). Unexpectedly, SILs were also identified in 127 of 9,666 control negative smears (1.3%; 95% CI: 1.1% to 1.5%). Compared with historical performance data from several participating laboratories, the instrument increased the detection rate of SILs in control smears by 25% and increased the yield of quality control rescreening 5.1 times (P < 0.0001). These data provide evidence that conventional screening and quality control rescreening of cervical smears fail to identify a substantial number of abnormalities. A significant improvement in performance of screening of cervical smears could be achieved with the use of the instrument described in this report.