Metatranscriptomic analysis of ectomycorrhizal roots reveals genes associated with Piloderma-Pinus symbiosis: improved methodologies for assessing gene expression in situ.

Ectomycorrhizal (EM) fungi form symbiotic associations with plant roots that regulate nutrient exchange between forest plants and soil. Environmental metagenomics approaches that employ next-generation sequencing show great promise for studying EM symbioses; however, metatranscriptomic studies have been constrained by the inherent difficulties associated with isolation and sequencing of RNA from mycorrhizae. Here we apply an optimized method for combined DNA/RNA extraction using field-collected EM fungal-pine root clusters, together with protocols for taxonomic identification of expressed ribosomal RNA, and inference of EM function based on plant and fungal metatranscriptomics. We used transcribed portions of ribosomal RNA genes to identify several transcriptionally dominant fungal taxa associated with loblolly pine including Amphinema, Russula and Piloderma spp. One taxon, Piloderma croceum, has a publically available genome that allowed us to identify patterns of gene content and transcript abundance. Over 1500 abundantly expressed Piloderma genes were detected from mycorrhizal roots, including genes for protein metabolism, cell signalling, electron transport, terpene synthesis and other extracellular activities. In contrast, Piloderma gene encoding an ammonia transporter showed highest transcript abundance in soil samples. Our methodology highlights the potential of metatranscriptomics to identify genes associated with symbiosis and ecosystem function using field-collected samples.

Prevalence and risk factors for obstetric haemorrhage in 6730 singleton births after assisted reproductive technology in Victoria Australia.

BACKGROUND: Obstetric haemorrhages have been reported to be increased after assisted reproduction technologies (ART) but the mechanisms involved are unclear. METHODS: This retrospective cohort study compared the prevalence of antepartum haemorrhage (APH), placenta praevia (PP), placental abruption (PA) and primary post-partum haemorrhage (PPH) in women with singleton births between 1991 and 2004 in Victoria Australia: 6730 after IVF/ICSI, 24 619 from the general population, 779 after gamete intrafallopian transfer (GIFT) and 2167 non-ART conceptions in infertile patients. Risk factors for haemorrhages in the IVF/ICSI group were examined by logistic regression. RESULTS: The IVF/ICSI group had more APH: 6.7 versus 3.6% (adjusted OR 2.0; 95% CI 1.8-2.3), PP: 2.6 versus 1.1% (2.3; 1.9-2.9), PA: 0.9 versus 0.4% (2.1; 1.4-3.0) and PPH: 11.1 versus 7.9% (1.3; 1.2-1.4) than the general population. APH, PP and PA were as frequent in the GIFT group as in the IVF/ICSI group, but were less frequent in the non-ART group. Within the IVF/ICSI group, fresh compared with frozen thawed embryo transfers (FET) was associated with more frequent APH (1.5; 1.2-1.8) and PA (2.1; 1.2-3.7) and the odds ratio increased with number of oocytes collected (1.02; 1.00-1.04). Endometriosis patients had more PP (1.7; 1.2-2.4) and PPH (1.3; 1.1-1.6) than those without endometriosis. FET in artificial cycles was associated with increased PPH (1.8; 1.3-2.6) compared with FET in natural cycles. CONCLUSIONS: Obstetric haemorrhages are more frequent with singleton births after IVF, ICSI and GIFT. The exploratory analysis of factors in the IVF/ICSI group, showing associations with fresh embryo transfers in stimulated cycles, endometriosis and hormone treatments, suggests that events around the time of implantation may be responsible and that suboptimal endometrial function is the critical mechanism.

The need for special foods and sugar substitutes by individuals with diabetes mellitus.

The need for special dietary products marketed for use by individuals with diabetes mellitus and the safety and efficacy of certain nutritive sweetener substitutes for sucrose are reviewed. Special foods for individuals with diabetes mellitus are not necessary to achieve the dietary objectives recommended by leading United States and European authorities. They can be achieved conveniently and at minimum expense through enlightened choices of commonly available food items. At present, specific and unique characteristics of food products with special therapeutic properties for diets of diabetic individuals cannot be delineated or defined on rational nutritional grounds. Such terms as "diet", "dietetic", and "diabetic" on food labels have no uniform meaning for consumers, and diabetologists have observed that patients tend to consume such foods without regard to their energy content. Some consumers regard the reduced-calorie and low-calorie prepared food products as convenient in diets for weight reduction and diabetes although their use in dietary management of diabetes has no therapeutic basis other than weight reduction and maintenance. When fed as pure substances to fasted subjects, the nonglucose carbohydrate nutritive sweeteners, fructose, xylitol, and sorbitol, are absorbed relatively slowly and produce less postprandial hyperglycemia and insulin response than sucrose or glucose. Adequate studies of their long-term effectiveness when ingested as part of mixed meals have not been conducted. Although these sucrose substitutes are generally considered safe, the significance of recent information on possible carcinogenicity of oral xylitol in long-term feeding studies has not been fully evaluated. In view of the lack of certain essential information on the long-term effectiveness of various diets in preventing or mitigating the chronic debilitating complication of diabetes, suggestions for future research are included.

Collection of human oocytes at laparoscopy and laparotomy.

PIP: In order to determine whether ovarian follicular aspiration at laparoscopy would provide enough oocytes for adequate in vitro studies, oocytes were collected during the periovulatory stage of the normal menstrual cycle from 45 women undergoing laparoscopy and from 25 women undergoing laparotomy. A larger average number of oocytes was recovered per patient at laparotomy due to better oocyte recoveries from ovarian wedges. However, the average number of oocytes rocovered per patient was the same at both procedures, providing that a suction vacuum of 200 mm Hg was used at laparoscopy, and under these conditions a greater percentage of follicles yielded oocytes at laparoscopy. Overall, 498 follicles were aspirated and 217 oocytes collected; the average recovery was 3 per patient. Moreover, the mean follicular diameter was 9.1 mm in infertile and 8.0 mm in fertile patients (p less than .05).^ieng

A clinical assessment of nine pregnancies obtained by in vitro fertilization and embryo transfer.

An analysis of nine pregnancies resulting from in vitro fertilization and embryo transfer was made in order to identify factors common to all of the pregnancies. These factors included clomiphene stimulation; general anesthesia for laparoscopy; identification of large follicles (greater than 8 ml) and a mature oocyte; preincubation of the oocyte for 4.7 to 6.5 hours in vitro before insemination; insemination with 0.8 to 1.3 x 10(6) fresh spermatozoa from fertile samples; transfer to the uterus of two-, four-, and eight-cell embryos, 38 to 50 hours after insemination; and uncomplicated uterine transfers of embryos. It was difficult to determine whether these factors are causal or coincidental in the attainment of successful pregnancies. The detailed analysis was useful in demonstrating factors which did not prevent the establishment of pregnancy by in vitro fertilization and embryo transfer. These factors included a variety of causes of infertility, including idiopathic and male infertility; age of the infertile woman over 35 years; the presence of T-mycoplasma in the genital tract; the use of human chorionic gonadotropin; a variety of agents used for general anesthesia; the use of carbon dioxide to induce pneumoperitoneum; a delay of up to 50 minutes in the interval between the induction of general anesthesia and oocyte recovery; the use of antiprostaglandins at the time of embryo transfer; and a brown discharge from the vagina following embryo transfer.

Fibrous dysplasia of the temporal bone: reversal of sensorineural hearing loss after decompression of the internal auditory canal.

When fibrous dysplasia affects the temporal bone, it most often presents with conductive hearing loss attributable to stenosis of the external auditory canal. Sensorineural hearing loss has usually been attributed to involvement of the otic capsule. We present a patient with bilateral fibrous dysplasia of the temporal bones who complained of unilateral hearing loss, facial tingling, and facial twitching. The audiogram showed severe sensorineural hearing loss. The hearing markedly improved and facial twitching and tingling ceased after decompression of the internal auditory canal via a middle fossa approach. This is the only case of which we are aware showing reversal of sensorineural hearing loss caused by fibrous dysplasia.

Congenital encephalocele of the medial skull base.

Meningoencephaloceles of the temporal bone are rare. Although most often seen following otologic surgery or trauma, congenital meningoencephaloceles can exist. The clinical presentation, diagnostic evaluation, and surgical management of three patients with congenital meningoencephalocele are presented. Two of the three patients presented to our institution with recurrent episodes of meningitis; one presented with partial complex seizures. Diagnostic evaluation included temporal bone computed tomography with magnetic resonance imaging. In two patients, defects were imaged following high-pressure subarachnoid cisternography with computed tomography. All three patients were found to have congenital defects in the area of Meckel's cave. Early recognition of congenital meningoencephalocele is important to avoid delay of definitive surgical management and neurologic sequelae.

MRI detection of cervical metastasis from differentiated thyroid carcinoma.

BACKGROUND: With the advent of the use of serum thyroglobulin as a marker for the recurrence of well-differentiated thyroid cancer (WDTC) after total thyroidectomy, clinicians are increasingly faced with the diagnostic dilemma of detecting the site of recurrence in thyroglobulin-positive patients with normal clinical examinations. The high protein content of this thyroglobulin may make it specifically detectable by magnetic resonance (MR) imaging. OBJECTIVE: To determine the ability of MR imaging to detect the presence of metastatic WDTC in cervical lymph nodes. STUDY DESIGN: Retrospective cohort. METHODS: Blinded review by two independent head and neck radiologists of 34 head and neck MR scans obtained from 26 patients with thyroid cancer (12 with primary disease and 14 with recurrent disease) all of whom subsequently underwent surgical removal of the lymph nodes considered at risk by imaging. RESULTS: The average overall percent sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and accuracy of MR imaging were 95%, 51%, 84%, 78%, and 83%, respectively. The concordance between the two radiologists was 69%. There was no overall difference in the ability of the MR scan to detect the presence of disease in the upper jugular, lower jugular, or paratracheal nodal stations. However, it was more useful for papillary carcinoma (PPV 86%, accuracy 85%) than for follicular carcinoma or the follicular variant of papillary carcinoma (PPV 63%, accuracy 67%). CONCLUSION: MR imaging is a sensitive and accurate technique for the detection of WDTC, particularly papillary carcinoma, metastatic to cervical lymph nodes. However, the lower specificity of this modality precludes its use as a screening tool.

Magnetic resonance imaging-enhancing lesions of the labyrinth and facial nerve. Clinical correlation.

OBJECTIVE: Gadolinium-enhanced magnetic resonance imaging (MRI) is useful in assessing inflammatory and neoplastic lesions of the labyrinth and facial nerve. The following cases demonstrate the ability of MRI to differentiate neoplastic from inflammatory lesions within the labyrinth. PATIENTS OR OTHER PARTICIPANTS: Nine patients were selected with enhancing lesions of the labyrinth and the facial nerve identified on MRI. INTERVENTION: Acyclovir and prednisone were prescribed for herpes zoster oticus; surgical removal of neoplastic lesions was performed. MAIN OUTCOME MEASURE: The hypothesis was developed in the course of clinical practice. No planned outcome was emphasized, as this article is based on the differential diagnoses of the cases reported. RESULTS: Gadolinium-enhanced MRI is useful in differentiating neoplastic from inflammatory lesions within the labyrinth. Axial and coronal 3-mm sections with gadolinium enhancement were necessary for identifying these lesions and particularly for recognizing the sharp enhancement of the neoplastic margin in contrast to the dull cloudy margins of an inflammatory lesion. CONCLUSIONS: The MRI differentiation of these lesions is helpful in providing appropriate medical and surgical management of neoplastic and inflammatory lesions of the labyrinth.

Accuracy of computed tomography in determining the presence or absence of metastatic retropharyngeal adenopathy.

OBJECTIVE: To decide the accuracy of computed tomography in determining the presence or absence of metastatic retropharygeal adenopathy in patients with squamous cell carcinoma of the head and neck. DESIGN: A comparison of the results of retrospective blinded review of preoperative computed tomographic scans with the histologic findings of retropharyngeal node dissection at the time of surgery. SETTING: Academic tertiary care center. PATIENTS: Twenty-six patients with advanced stage squamous cell carcinoma of the head and neck. MAIN OUTCOME MEASURES: Computed tomographic findings and histologic results of retropharyngeal node dissection. RESULTS: The retropharyngeal nodes were pathologically positive for metastasis in 6 (23%) of the 26 patients. The radiologist (J.M.T.) correctly read the scan in 3 of 6 patients with histologically proved metastasis, and in 14 of 20 patients with histologic features negative for metastasis. The sensitivity of the radiologist reading was 50%, and the specificity was 70%. The positive predictive value was 33%, and the negative predictive value was 82%. CONCLUSION: The presence of retropharyngeal node metastasis cannot be determined by computed tomographic imaging alone. Arch Otolaryngol Head Neck Surg. 2000;126:1478-1481

Electrochemical analysis of surfactants: An overview.

This work presents an overview of electrochemical techniques, namely potentiometry, amperometry, tensammetry, electrocapillary measurements and biosensors, recently applied for the determination of surfactants.

Molecular analysis of the POU3F4 gene in patients with clinical and radiographic evidence of X-linked mixed deafness with perilymphatic gusher.

The molecular defect in some patients with X-linked mixed deafness with perilymphatic gusher at stapes surgery (DFN3) was recently attributed to mutations in the POU3F4 gene. In this manuscript we describe the molecular analysis of the POU3F4 gene in 5 patients with clinical and radiographic evidence of DFN3. Novel mutations were found in 2 of the 5 patients analyzed, while 3 had an entirely normal protein coding sequence. The fact that 3 of the 5 patients with clinical histories and radiographic abnormalities characteristic of X-linked mixed deafness with perilymphatic gusher displayed normal POU3F4 gene sequences supports the possibility that not all patients with the characteristic phenotype have involvement of the POU3F4 gene.

A review of the psychological aspects of space flight.

Instances of overt, serious functional impairment of space crews caused by adverse psychologic responses have not been scientifically documented. However, transient disorientation, spatial illusions, and visual disturbances as well as anomalous myopias, sleep disturbances, and instances of substandard performance have been described. Moreover, anecdotal information describes significant psychologic aberrations in space flight. Adequate scientific data are lacking for optimal psychological and psychophysiological methods for crew selection, training, and performance evaluation, for identifying key psychosocial factors for crew compatibility, cohesiveness, and productivity, and for determining the effects of space flight on perceptual, intellectual, and motor skills. The ad hoc Working Group, convened to review psychological aspects of space flight, favored establishment of a comprehensive research and development program to address the deficiencies identified in the study.