[Malignant gastrointestinal neuroectodermal tumor: a clinicopathological analysis of three cases].

Objective: To investigate the clinicopathological characteristics of malignant gastrointestinal neuroectodermal tumors (GNET), and to describe their clinical, histological, immunophenotypic, ultrastructural, and molecular features, diagnosis and differential diagnosis. Methods: Three cases of malignant GNET were collected at Xijing Hospital of the Fourth Military Medical University, from 2013 to 2022. All patients underwent surgical resection of the tumor. Histological, immunohistochemical (IHC), ultrastructural and molecular genetic analyses were performed, and the patients were followed up for six months, three years and five years. Results: There were two males and one female patients. The tumors were located in the ileum, descending colon, and rectum, respectively. Grossly, the tumors were solid, firm, and poorly circumscribed, measured in size from 2 to 4 cm in greatest dimension, and had a greyish-white cut surface. These tumors were histologically characterized by a sheet-like or nested population of oval to spindled cells or epithelioid cells with weakly eosinophilic or clear cytoplasm, small nucleoli and scattered mitoses. Electron microscopy showed neuroendocrine differentiation, and no evidence of melanogenesis. IHC staining showed that the tumor cells were diffusely positive for S-100 protein, SOX10, CD56, synaptophysin and vimentin. They were negative for melanocytic markers, HMB45 and Melan A. All three cases showed split EWSR1 signals consistent with a chromosomal translocation involving EWSR1. Next-generation sequencing in one case confirmed the presence of EWSR1-ATF1 fusion. These patients were followed up for 6 months, 3 years and 5 years, respectively, and all of them developed possible lung or liver metastases, and one of them died of multiple pulmonary metastases. Conclusion: Malignant GNET has distinctive morphological, IHC, and molecular genetic features and it should be differentiated from other malignancies of the gastrointestinal tract, especially clear cell sarcoma and melanoma.

Update on the Recommendations on Breast Cancer Screening by the Cancer Expert Working Group on Cancer Prevention and Screening.

Breast cancer (BC) is the most common cancer among women in Hong Kong. The Food and Health Bureau commissioned The University of Hong Kong (HKU) to conduct the Hong Kong Breast Cancer Study (HKBCS) with the aim of identifying relevant risk factors for BC in Hong Kong and developing a locally validated BC risk assessment tool for Hong Kong Chinese women. After consideration of the most recent international and local scientific evidence including findings of the HKBCS, the Cancer Expert Working Group on Cancer Prevention and Screening (CEWG) has reviewed and updated its BC screening recommendations. Existing recommendations were preserved for women at high risk and slightly changed for women at moderate risk. The following major updates have been made concerning recommendations for other women in the general population: Women aged 44 to 69 with certain combinations of personalised risk factors (including presence of history of BC among first-degree relative, a prior diagnosis of benign breast disease, nulliparity and late age of first live birth, early age of menarche, high body mass index and physical inactivity) putting them at increased risk of BC are recommended to consider mammography screening every 2 years. They should discuss with their doctors on the potential benefits and harms before undergoing mammography screening. A risk assessment tool for local women (eg, one developed by HKU) is recommended to be used for estimating the risk of developing BC with regard to the personalised risk factors described above.

MiR-424 Inhibits neuronal apoptosis in rats with cerebral infarction through regulating TGF-ß1/Smad3 signaling pathway.

It has been reported that micro ribonucleic acid (miR)-424 is an important molecule in cerebral ischemia. However, the precise mechanism of action and biological effects of miR-424 remain to be further explored. miR-424 mimic and miR-424 inhibitor were injected via the caudal vein in rats, and the effect of miR-424 expression on brain tissue damage induced by middle cerebral artery occlusion (MCAO) was detected. The miR-424 mimic-induced changes in genomic levels were detected via the gene chip assay, and the signaling pathways regulated by miR-424 and its potential targets were explored combined with target prediction. Then the effect of miR-424 mimic on apoptosis of PC12 cells induced by oxygen-glucose deprivation (OGD) was determined using Annexin V/PI assay. Finally, drosophila mothers against decapentaplegic protein 7 (Smad7) was overexpressed to further verify the mechanism of action of miR-424 mimic. Compared with that in the sham group, the expression of miR-424 in brain tissues significantly declined in the model group. The results of 2,3,5-triphenyltetrazolium chloride (TTC) staining and terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL) assay revealed that the miR-424 mimic obviously reduced the cerebral infarction area and apoptosis level of brain tissues, while the miR-424 inhibitor obviously increased the cerebral infarction area and apoptosis level of brain tissues. It was found, using bioinformatics and KEGG enrichment analysis, that differentially expressed genes induced by miR-424 were significantly enriched in the transforming growth factor-ß (TGF-ß) signaling pathway. According to the results of reverse transcription-quantitative polymerase chain reaction (RT-qPCR) and Western blotting, the miR-424 mimic could evidently lower the expression of Smad7, thus activating the TGF-ß1/Smad3 signaling pathway. Overexpression of Smad7 could weaken the protective effect of miR-424 mimic on ischemic-hypoxic cells. Increasing the expression of miR-424 can inhibit Smad7 to activate the TGF-ß1/Smad3 signaling pathway, thereby exerting a protective effect against the brain tissue damage induced by MCAO.

Antibiotic management of acute pharyngitis in primary care.

The Centre for Health Protection of the Department of Health has convened the Advisory Group on Antibiotic Stewardship Programme in Primary Care (the Advisory Group) to formulate guidance notes and strategies for optimising judicious use of antibiotics and enhancing the Antibiotic Stewardship Programme in Primary Care. Acute pharyngitis is one of the most common conditions among out-patients in primary care in Hong Kong. Practical recommendations on the diagnosis and antibiotic treatment of acute streptococcal pharyngitis are made by the Advisory Group based on the best available clinical evidence, local prevalence of pathogens and associated antibiotic susceptibility profiles, and common local practice.

Genetic Structure Analysis of Y-Chromosome STR and SNP in Population of Wujiang Area, Suzhou City.

ABSTRACT: Objective To analyze the genetic phenotypes of Y-chromosome STR and SNP in Han male population of Wujiang area, Suzhou City and explore the genetic structure of population of Wujiang area for further examination of regional-specific Y-SNP genetic markers ancestor haplogroups. Methods Blood samples of 472 Wujiang area Han males were randomly collected and genotyped by YfilerTM Plus PCR Amplification Kit. The allele frequencies and haplotype frequencies of each locus were obtained using the direct calculation method. Y-SNP haplogroups of each sample were estimated using Y-Predictor software and verified through experiments by amplification refractory mutation system-polymerase chain reaction （ARMS-PCR）. Results A total of 453 haplotypes were found in the 27 Y-STR genetic markers in 472 Han males of Wujiang area. The haplotype diversity （HD） was 0.997 696 93, among which, the highest gene diversity （GD） value was DYF387S1a/b （GD=0.953 1） and the lowest was DYS438 （GD=0.321 8）. Based on genotyping data of 27 Y-STRs and 472 samples, 132 haplogroups from C, D, N, O and Q, etc downstream Y-SNP haplogroups were estimated and then verified through experiments. Conclusion This study is based on Y-chromosome STR haplotypes, and predicts Y-SNP haplogroups by Y-Predictor software, then uses ARMS-PCR to verify. Y-SNP genetic markers were introduced to achieve precise analysis of the genetic structure of male families in population of three towns in Wujiang area.

[Incidence and influencing factors of continuous positive airway pressure treatment-emergent central sleep apnea in the patients with obstructive sleep apnea syndrome at high altitude].

Objective: To investigate the incidence of treatment-emergent central sleep apnea (TE-CSA), the characteristics of demography and the influencing factors in patients with obstructive sleep apnea syndrome (OSAS) after initial continuous positive airway pressure (CPAP) titration at high altitude. Methods: Clinical data of 297 patients with OSAS which living in plateau areas (1 000 meters or more above sea level) were retrospectively analyzed in this study from January to December, 2015. All of these patients taken an overnight CPAP titration in the Sleep Medicine Center of First People's Hospital of Yunnan Province. They were classified as with TE-CSA group and non TE-CSA group according to the outcome of CPAP titration. Comparisons of demographic characteristic, parameters of polysomnography in CPAP titration night, lung function test and blood gas analysis were made between the two groups, respectively, and statistical analysis was carried. Results: The incidence of TE-CSA was 16.5% (49/297) after initial CPAP titration at high altitude, which was higher in male patients (18.2% vs 6.8%, P=0.061). The incidence of TE-CSA decreased with the increase of age and body mass index (BMI), and the decrease of resident altitude. Multivariate Logistic regression analysis showed that the resident altitude, mixed apnea index (MAI), forced expiratory volume in 1 second (FEV(1)) and forced vital capacity (FVC) ratio, functional residual capacity (RV) and total lung capacity (TLC) ratio were the main factors affecting the occurrence of TE-CSA. Among them, the increase of resident altitude and MAI were risk factors [OR=1.16(1.02, 1.32), 1.05(1.01, 1.09)]. The increase of FEV(1)/FVC and RV/TLC were protective factors [OR=0.94(0.89, 0.98), 0.94(0.88, 0.99)]. Conclusion: The incidence of TE-CSA is high at high altitude area, and the increase of resident altitude and MAI are the risk factors for TE-CSA.

[Field investigation of occupational disease diagnosis in Guangdong Provincial Hospital for Occupational Disease Prevention and Treatment from 2009 to 2014: an analysis of 136 cases].

OBJECTIVE: To investigate the characteristics of 136 patients with occupational diseases, to summarize key techniques used in field investigation, and to provide a scientific basis for the development of standard operating procedures for field investigation of occupational disease diagnosis. METHODS: Field investigation and routine data analysis were performed to analyze the cases diagnosed by Guangdong Provincial Hospital for Occupational Disease Prevention and Treatment from January 2009 to December 2014. RESULTS: A total of 136 cases of occupational diseases were diagnosed by Guangdong Provincial Hospital for Occupational Disease Prevention and Treatment from 2009 to 2014, and there were 66 cases of leukemia, 18 cases of suspected occupational benzene poisoning, 12 cases of suspected occupational handarm vibration disease, and 11 cases of suspected pneumoconiosis. Of all these patients, 41.91% were engaged in at least three types of work, 70.59% were exposed to at least three types of chemicals, 25.74% experienced changes in technical processes and chemicals, and 47.06% had disputes on the chemicals they were exposed to during verification by both parties. Occupational hazard factors were detected. Most samples (358)were used to measure benzene concentration in workplace air, among which 11.7% had a benzene concentration of >6.00 mg/m(3)(exceeding standard), 13.41% had a benzene concentration of 3.26~6.00 mg/m(3), 75.42% had a benzene concentration of<0.03 to <3.25 mg/m(3). The samples of suspected occupational hand-arm vibration disease, suspected pneumoconiosis, and suspected occupational noiseinduced hearing loss had high overstandard rates (100%, 93.8%, and 83.3%, respectively). CONCLUSION: Field investigation of occupational disease diagnosis reveals large numbers of cases of leukemia, suspected occupational benzene poisoning, suspected occupational hand-arm vibration disease, and suspected pneumoconiosis. The key aspects of field investigation include confirmation of the history of occupational exposure, identification of occupational hazard factors, confirmation of the changes in technical processes and chemicals, detection of occupational hazard factors, sampling and analysis of raw materials, and epidemiological investigation of workers with the same type of work.

Stereotactic ablative radiotherapy with CyberKnife for advanced thymic carcinoma: a case report.

Thymic carcinoma is a rare but lethal mediastinal cancer. The optimal treatment for advanced thymic carcinoma is not yet established. This report is the first known of stereotactic ablative radiotherapy (sabr) with CyberKnife (Accuray, Sunnyvale, CA, U.S.A.) as definitive therapy for thymic carcinoma. The patient, a 70-year-old woman with thymic carcinoma, invasion into neighboring organs, and pleural metastases-underwent CyberKnife sabr at 40 Gy in 5 fractions for two lesions, one in the thymus and one in the right paraspinal pleura. After 61 months of observation, a partial response was observed in the irradiated fields. However, disease progression in the non-irradiated pleura was noted. The patient underwent salvage CyberKnife sabr for the four initially nonirradiated pleural lesions. Computed tomography images obtained 10 months after the salvage therapy revealed a partial response. The patient is living, with progression-free irradiated lesions and no radiation-related toxicity. CyberKnife sabr is feasible for patients who are unable to undergo either surgery or conventionally fractionated radiation therapy.

Hot plasma environment at jupiter: voyager 2 results.

Measurements of the hot (electron and ion energies >/=20 and >/= 28 kiloelectron volts, respectively) plasma environment at Jupiter by the low-energy charged particle (LECP) instrument on Voyager 2 have revealed several new and unusual aspects of the Jovian magnetosphere. The magnetosphere is populated from its outer edge into a distance of at least approximately 30 Jupiter radii (R(J)) by a hot (3 x 10(8) to 5 x 10(8) K) multicomponent plasma consisting primarily of hydrogen, oxygen, and sulfur ions. Outside approximately 30 R(J) the hot plasma exhibits ion densities from approximately 10(-1) to approximately 10(-6) per cubic centimeter and energy densities from approximately 10(-8) to 10(-13) erg per cubic centimeter, suggesting a high beta plasma throughout the region. The plasma is flowing in the corotation direction to the edge of the magnetosphere on the dayside, where it is confined by solar wind pressure, and to a distance of approximately 140 to 160 R(J) on the nightside at approximately 0300 local time. Beyond approximately 150 R(J) the hot plasma flow changes into a "magnetospheric wind" blowing away from Jupiter at an angle of approximately 20 degrees west of the sun-Jupiter line, characterized by a temperature of approximately 3 x 10(8) K (26 kiloelectron volts), velocities ranging from approximately 300 to > 1000 kilometers per second, and composition similar to that observed in the inner magnetosphere. The radial profiles of the ratios of oxygen to helium and sulfur to helium (

Low-energy charged particle environment at jupiter: a first look.

The low-energy charged particle instrument on Voyager was designed to measure the hot plasma (electron and ion energies greater, similar 15 and greater, similar 30 kiloelectron volts, respectively) component of the Jovian magnetosphere. Protons, heavier ions, and electrons at these energies were detected nearly a third of an astronomical unit before encounter with the planet. The hot plasma near the magnetosphere boundary is predominantly composed of protons, oxygen, and sulfur in comparable proportions and a nonthermal power-law tail; its temperature is about 3 x 10(8) K, density about 5 x 10(-3) per cubic centimeter, and energy density comparable to that of the magnetic field. The plasma appears to be corotating throughout the magnetosphere; no hot plasma outflow, as suggested by planetary wind theories, is observed. The main constituents of the energetic particle population ( greater, similar200 kiloelectron volts per nucleon) are protons, helium, oxygen, sulfur, and some sodium observed throughout the outer magnetosphere; it is probable that the sulfur, sodium, and possibly oxygen originate at 1o. Fluxes in the outbound trajectory appear to be enhancedfrom approximately 90 degrees to approximately 130 degrees longitude (System III). Consistent low-energy particle flux periodicities were not observed on the inbound trajectory; both 5-and 10-hour periodicities were observed on the outbound trajectory. Partial absorption of > 10 million electron volts electrons is observed in the vicinity of the Io flux tube.

Effect of chlorhexidine bathing on colonization or infection with Acinetobacter baumannii: a systematic review and meta-analysis.

Healthcare-associated infections (HAIs) caused by multi-drug-resistant Gram-negative bacteria (MDRGNB) have increased prevalence in intensive care units (ICUs). A common strategy to prevent HAIs is bathing patients with chlorhexidine gluconate (CHG). However, the effectiveness of CHG bathing against multidrug-resistant Acinetobacter baumannii (MDRAB) is still controversial. The aim of this study was to perform a systematic review and meta-analysis of the effectiveness of CHG bathing on Acinetobacter baumannii colonization and infection in the ICU setting. A systematic literature search of PubMed, EMBASE, Web of Science and CINAHL was performed from inception through to June 2018. Randomized controlled trials (RCTs), pre-post studies, or interrupted time series (ITS) studies were included. The numbers of patients with/without colonization or infection of A. baumannii in the experimental or control groups were extracted from each study. Quality assessment was performed by the related instruments of National Institute of Health. Pooled risk ratios (RRs) were calculated using the random-effects model. One RCT and 12 pre-post or ITS studies comprising 18,217 patients were included, of which 8069 were in the CHG bathing arm and 9051 in the control arm. CHG bathing was associated with a reduced colonization of A. baumannii (RR, 0.66; 95% confidence interval: 0.57-0.77; P<0.001). Chlorhexidine at 4% showed a better effect than 2% chlorhexidine (meta-regression P=0.044). CHG bathing was associated with a non-significant reduction of infection (pooled RR 0.41, 95% CI: 0.13-1.25). This study suggests that CHG bathing significantly reduces colonization of A. baumannii in the ICU setting. However, more trials are needed to confirm whether CHG bathing can reduce infections with A. baumannii.

[The relevance between obstructive sleep apnea hypopnea syndrome andchronic obstructive pulmonary disease in China: A Meta-analysis].

Objective:To assess the correlation between obstructive sleep apnea hypopnea syndrome(OSAHS) and chronic obstructive pulmonary disease(COPD).Method: Databases such as Chinese Biomedical Literature Database, PubMed, Chinese Academic Journals full-text database, Wanfang Resource Database and Chongqing VIP have been searched to collect literatures about the relationship between OSAHS and COPD. The literature in conference proceedings and certain unpublished articles were also manually retrieved. RCT conformed to the condition was evaluated according to the standards of literature assessment, and the data has been extracted. The RevMan5.3 software was applied to carry out the same Metaanalysis.Result: Totally 19 articles were included, and Metaanalysis reveal that overlap syndrome(OS) patient's apnea hypopnea index is significantly higher than those of OSAHS patients［WMD=7.56, 95%CI（4.19,10.94）, P<0.01］; The LSaO2 of OS patients is significantly lower than OSAHS patients［WMD=-10.50, 95%CI(-11.58, -6.08),P<0.01］; OS patients' FEV1/FVC is significantly lower than COPD patients［WMD=4.65,95%CI（1.15,8.15）,P<0.01］.The results revealed that subgroup analysis according to the sample volume, age, body mass index(BMI) and FEV1/FVC between OS patients and OSAHS patients has heterogeneity, but when analysis with the score of ESS the heterogeneity does not exist. Further, the subgroup analysis according to the sample volume, BMI, AHI,LSaO2 and the time of Oxygen is lower than 90%(T90) those index between OS patients and COPD patients has heterogeneity, and the heterogeneity does not exist when subgroup is analyses with neck circumference. The funnel schema was nearly symmetry with little bias.Conclusion:The experimental results indicate that OSAHS is significantly related with COPD, and they may be the mutual risk factor for each other..

cDNA sequence analysis and expression of four long neurotoxin homologues from Naja naja atra.

The novel cDNAs encoding four long neurotoxin homologues were firstly cloned from the venom gland of Naja naja atra by reverse transcriptase-polymerase chain reaction. Amino acid sequence comparison showed that they may come from two different evolutionary origins. The mature proteins were expressed as soluble fusion proteins in Escherichia coli and purified for immunoblotting. The results revealed that they displayed different immunochemical properties.

The adverse effects of long-term l-carnitine supplementation on liver and kidney function in rats.

Levo-Carnitine (l-carnitine) is widely used in health and food. This study was to focus on the adverse effects of 8-week oral supplementation of l-carnitine (0.3 and 0.6 g/kg) in female and male Sprague Dawley rats. l-carnitine reduced body and fat weights, as well as serum, liver, and kidney lipid levels in rats. Simultaneously, hepatic fatty acid ß-oxidation and lipid synthesis were disturbed in l-carnitine-fed rats. Moreover, l-carnitine accelerated reactive oxygen species production in serum and liver, thereby triggering hepatic NOD-like receptor 3 (NLRP3) inflammasome activation to elevate serum interleukin (IL)-1ß and IL-18 levels in rats. Alteration of serum alkaline phosphatase levels further confirmed liver dysfunction in l-carnitine-fed rats. Additionally, l-carnitine may potentially disturb kidney function by altering renal protein levels of rat organic ion transporters. These observations may provide the caution information for the safety of long-term l-carnitine supplementation.

Expression of androgen receptor and prostatic specific markers in salivary duct carcinoma: an immunohistochemical analysis of 13 cases and review of the literature.

Salivary duct carcinoma (SDC) is an uncommon, pathologically distinct entity characterized by its morphologic resemblance to ductal carcinoma of the breast and highly aggressive behavior. Approximately two thirds of patients die within 4 years of initial diagnosis despite aggressive, combined surgical resection and radiotherapy. Review of the literature indicates that androgen receptor (AR), a marker frequently detected in prostatic carcinoma, is expressed in over 90% of SDCs, whereas two common breast carcinoma markers, estrogen and progesterone receptors (ER and PR), are expressed in only 1.3% and 6% of the tumors, respectively, by immunohistochemistry. This hormonal profile suggests that SDC, in contrast to its histiologic similarity to ductal carcinoma of the breast, is immunophenotypically more related to prostatic carcinoma. To substantiate this hypothesis, we performed immunohistochemical staining of 13 cases of SDC for the presence of AR and two prostatic markers, prostate specific antigen (PSA) and prostatic acid phosphatase (PAP). Our results showed multifocal, scattered, moderate immunostaining for PAP and diffuse, moderate immunostaining for PSA in seven (58.3%) and two (16.7%) cases, respectively. These results create a potential diagnostic challenge to surgical pathologists who are dealing with a metastatic adenocarcinoma of AR+/PSA+/-/PAP+/- phenotype, particularly in male patients of unknown primary. Metastatic salivary duct carcinoma should be given serious thought if clinical investigation fails to reveal a prostatic primary. The immunophenotypic homology that exists between SDC and prostatic carcinoma also suggests that antiandrogen therapy as used in the treatment of prostatic carcinoma might be beneficial in patients with metastatic SDC when all other conventional modalities fail.

Expression of fas ligand in metastatic prostatic carcinoma: suggestive of possible clonal expansion of subpopulation with metastatic potential.

Fas ligand (FasL) is a type II transmembrane tumor necrosis factor family protein, known to trigger apoptosis in cells that bear the FasL receptor, Fas. The authors found that normal prostate, benign hyperplasia, and most prostatic carcinoma cells at the primary site did not express FasL, whereas metastatic prostatic carcinoma cells in lymph nodes and bone marrow displayed almost uniform, immunohistochemically detectable, FasL expression. However, small foci of FasL-positive prostatic carcinoma cells amid a vast majority of FasL-negative tumor cells were noted at the primary sites in patients with distant metastases. Analysis of the FasL gene and its mRNA by polymerase chain reaction and reverse transcriptase-polymerase chain reaction, respectively, suggested that the expression of immunohistochemically detectable FasL in metastatic tumor cells was not due to mutation in the FasL gene with resulting overexpression. Further, FasL expression was detectable in the acinar epithelial cells of prostates with morphologic atrophic changes, suggesting that FasL also plays a role in the physiologic apoptosis process of noncancerous prostate. The current data suggest that a subpopulation of prostate carcinoma cells clonally expresses FasL, and this subpopulation may have metastatic potential. Evaluation of FasL expression in the primary tumor thus may provide a useful parameter for predicting metastatic potential of the tumor.

Alkyltransferase transgenic mice: probes of chemical carcinogenesis.

Transgenic mice expressing DNA-repair genes are an instructive model with which to study the protective role of DNA-repair pathways in both spontaneous and chemical carcinogenesis. Of particular interest in chemical carcinogenesis is the DNA-repair protein O6-alkylguanine-DNA alkyltransferase (alkyltransferase) which repairs O6-alkylguanine-DNA adducts. Transgenic mice carrying expression constructs for the alkyltransferase gene--either the human MGMT cDNA or the bacterial ada gene--express increased levels of alkyltransferase and have increased capacity to remove O6-methylguanine-DNA adducts. Protection from the DNA damaging effects of N-nitroso compounds occurs specifically in the cells and tissues in which the alkyltransferase transgene is expressed. For instance, mice carrying the PEPCKada construct have increased alkyltransferase in the liver and more rapid removal of O6methylguanine-DNA adducts. The protective effect is noted in hepatocytes, which express PEPCK-linked genes, not in nonparenchymal cells of the liver, which do not. Other tissues that express the transgene in the various models include the thymus, spleen, testes, muscle, stomach and brain. Mice expressing the human alkyltransferase in the thymus have a reduced incidence of thymic lymphomas following exposure to methyl nitrosourea (MNU), evidence of a role for this DNA-repair protein in protection from carcinogenesis due to N-nitroso compounds. Protection has also been observed in the induction of hepatic tumors by N-nitroso-dimethylamine (NDMA). These models will be used to identify whether overexpression of a single DNA-repair gene can block the carcinogenic process of N-nitroso compounds in many different tissues.

Expression of androgen receptor, epidermal growth factor receptor, and transforming growth factor alpha in salivary duct carcinoma.

BACKGROUND: Salivary duct carcinoma (SDC) is a rare, highly aggressive neoplasm that primarily affects the major salivary glands. It is a distinct clinicopathological entity characterized by its morphologic resemblance to ductal carcinoma of the breast, a high incidence of regional lymph node metastasis, and distant dissemination. Frequent expression of androgen receptor (AR) but not estrogen receptor or progesterone receptor in SDCs suggests that SDC bears a close immunophenotypic homology with prostatic carcinoma. An AR-mediated autocrine growth pathway consisting of epidermal growth factor receptor (EGFR) and its ligand, transforming growth factor alpha (TGF-alpha), has been implicated in the carcinogenesis of prostatic carcinoma. Androgens, in the presence of AR, mediate their mitogenic effects on prostatic cancer cells by up-regulating the transcriptional and translational activities of EGFR and TGF-alpha. Through an autocrine mode of action, TGF-alpha produced in the tumor cells binds to its receptor, EGFR, which is also expressed by these cells, resulting in a proliferative response. OBJECTIVE: To investigate whether a TGF-alpha/EGFR autocrine pathway is present in SDCs. DESIGN: Retrospective analysis of the expression of AR, EGFR, and TGF-alpha in 12 SDCs. SETTING: An academic medical center. RESULTS: Salivary duct carcinoma expresses AR, TGF-alpha, and EGFR in 11 (92%), 8 (67%), and 11 (92%) of 12 cases, respectively. CONCLUSION: An AR-mediated TGF-alpha/EGFR autocrine pathway may be implicated in the tumorigenesis of SDC.

Demineralized bone matrix as an alternative for mastoid obliteration and posterior canal wall reconstruction: results in an animal model.

HYPOTHESIS: This study was conducted to evaluate the use of Grafton human demineralized bone matrix as a graft material for mastoid cavity obliteration and canal wall reconstruction in an animal model. BACKGROUND: Canal wall down procedures in the treatment of cholesteatoma may result in a problematic mastoid cavity. Elimination of the mastoid cavity by obliteration or canal wall reconstruction can prevent or correct this problem. Many techniques and implant materials have been used for this application, yet no single material has proven to be ideal. METHODS: Athymic rats received tympanic bulla obliteration and lateral bulla wall reconstruction utilizing the Grafton Putty and Flex formulations, respectively. Wound healing was monitored twice a week. Auditory brainstem evoked responses were obtained 8 weeks after implantation. Nine weeks after implantation, the animals were killed, and histologic sections were prepared. A histologic bone formation score (range 0-4) was determined for each implant. RESULTS: Wound healing occurred without complication. Auditory brainstem response thresholds (average 23.5) fell within the normal range for all ears tested. The average histologic bone formation score for all implants was 3.7. The average scores for obliteration implants and wall reconstruction implants were 3.5 and 3.9, respectively. All wall reconstruction implants underwent partial or total collapse into the bulla. CONCLUSIONS: The high level of bone formation obtained by the use of Grafton implants in this study makes this material a promising resource for use in mastoid obliteration. The use of the material for canal wall reconstruction will likely require a sturdier preparation to prevent collapse into the mastoid cavity.

Enzymes for enhancing bioremediation of petroleum-contaminated soils: a brief review.

During the 1950s and 1960s, hundreds of thousands of underground storage tanks (and above-ground storage tanks) containing petroleum products and hazardous chemicals were installed. Many of these tanks either have been abandoned or have exceeded their useful lives and are leaking, thereby posing a serious threat to the nation's surface and groundwater supplies, as well as to public health. Cleaning up releases of petroleum hydrocarbons or other organic chemicals in the subsurface environment is a real-world problem. Biological treatment of hydrocarbon-contaminated soil is considered to be a relatively low-cost and safe technology; however, its potential for effectively treating recalcitrant wastes has not been fully explored. For millions of years, microorganisms such as bacteria, fungi, actinomycete, protozoa, and others have performed the function of recycling organic matter from which new plant life can grow. This paper examines the biological treatment technology for cleaning up petroleum product-contaminated soils, with special emphasis on microbial enzyme systems for enhancing the rate of biodegradation of petroleum hydrocarbons. Classifications and functions of enzymes, as well as the microbes, in degrading the organic contaminants are discussed. In addition, the weathering effect on biodegradation, types of hydrocarbon degraders, advantages associated with enzyme use, methods of enzyme extraction, and future research needs for development and evaluation of enzyme-assisted bioremediation are examined.