Evaluation of microcalcification contrast in clinical images for digital mammography and synthetic mammography.

PURPOSE: The aim of this work was to compare, in a clinical study, digital mammography and synthetic mammography imaging by evaluating the contrast in microcalcifications of different sizes. METHODS: A retrospective review of microcalcifications from 46 patients was undertaken. A Hologic 3-Dimensions mammography system and a HD Combo protocol was used for simultaneous acquisition of the digital and synthetic images. Microcalcifications were classified in accordance with their size, and patient breast images were classified in accordance with their density as adipose, moderately dense and dense. The contrast of the microcalcifications was measured and the contrast ratio between synthetic and digital images was compared. An additional qualitative assessment of the images was presented to correlate the conspicuity of the microcalcifications with the suppression of the structure noise. RESULTS: Microcalcifications in adipose background always exhibit a comparable or better contrast on synthetic images, regardless their size. For moderately dense background, synthetic images show a better contrast in 91.2 % of cases for small microcalcifications and in 90.9 % of cases for large microcalcifications. For a dense background, better contrast is seen in 89.5 % of cases for small microcalcifications, and in 85.7 % of cases for large microcalcifications. The contrast ratio increases with increasing breast glandularity. The suppression of structure noise also contributes to the enhancement of microcalcifications in the synthetic images. CONCLUSIONS: Synthetic mammography imaging is superior to digital mammography imaging in terms of microcalcification contrast, regardless their size and breast density.

Assessment of structural chromosomal instability phenotypes as biomarkers of carboplatin response in triple negative breast cancer: the TNT trial.

BACKGROUND: In the TNT trial of triple negative breast cancer (NCT00532727), germline BRCA1/2 mutations were present in 28% of carboplatin responders. We assessed quantitative measures of structural chromosomal instability (CIN) to identify a wider patient subgroup within TNT with preferential benefit from carboplatin over docetaxel. PATIENTS AND METHODS: Copy number aberrations (CNAs) were established from 135 formalin-fixed paraffin-embedded primary carcinomas using Illumina OmniExpress SNP-arrays. Seven published [allelic imbalanced CNA (AiCNA); allelic balanced CNA (AbCNA); copy number neutral loss of heterozygosity (CnLOH); number of telomeric allelic imbalances (NtAI); BRCA1-like status; percentage of genome altered (PGA); homologous recombination deficiency (HRD) scores] and two novel [Shannon diversity index (SI); high-level amplifications (HLAMP)] CIN-measurements were derived. HLAMP was defined based on the presence of at least one of the top 5% amplified cytobands located on 1q, 8q and 10p. Continuous CIN-measurements were divided into tertiles. All nine CIN-measurements were used to analyse objective response rate (ORR) and progression-free survival (PFS). RESULTS: Patients with tumours without HLAMP had a numerically higher ORR and significantly longer PFS in the carboplatin (C) than in the docetaxel (D) arm [56% (C) versus 29% (D), PHLAMP,quiet = 0.085; PFS 6.1 months (C) versus 4.1 months (D), Pinteraction/HLAMP = 0.047]. In the carboplatin arm, patients with tumours showing intermediate telomeric NtAI and AiCNA had higher ORR [54% (C) versus 20% (D), PNtAI,intermediate = 0.03; 62% (C) versus 33% (D), PAiCNA,intermediate = 0.076]. Patients with high AiCNA and PGA had shorter PFS in the carboplatin arm [3.4 months (high) versus 5.7 months (low/intermediate); and 3.8 months (high) versus 5.6 months (low/intermediate), respectively; Pinteraction/AiCNA = 0.027, Padj.interaction/AiCNA = 0.125 and Pinteraction/PGA = 0.053, Padj.interaction/PGA = 0.176], whilst no difference was observed in the docetaxel arm. CONCLUSIONS: Patients with tumours lacking HLAMP and demonstrating intermediate CIN-measurements formed a subgroup benefitting from carboplatin relative to docetaxel treatment within the TNT trial. This suggests a complex and paradoxical relationship between the extent of genomic instability in primary tumours and treatment response in the metastatic setting.

Does prehabilitation modify muscle mass in patients with rectal cancer undergoing neoadjuvant therapy? A subanalysis from the REx randomised controlled trial.

BACKGROUND: Patients with rectal cancer who present with sarcopenia (low muscle mass) are at significantly greater risk of postoperative complications and reduction in disease-free survival. We performed a subanalysis of a randomised controlled study [the REx trial; www.isrctn.com ; 62859294] to assess the potential of prehabilitation to modify muscle mass in patients having neoadjuvant chemoradiotherapy (NACRT). METHODS: Patients scheduled for NACRT, then potentially curative surgery (August 2014-March 2016) had baseline physical assessment and psoas muscle mass measurement (total psoas index using computed tomography-based measurements). Participants were randomised to either the intervention (13-17-week telephone-guided graduated walking programme) or control group (standard care). Follow-up testing was performed 1-2 weeks before surgery. RESULTS: The 44 patients had a mean age of 66.8 years (SD 9.6) and were male (64%); white (98%); American Society of Anesthesiologists class 2 (66%); co-morbid (58%); overweight (72%) (body mass index ≥ 25 kg/m2). At baseline, 14% were sarcopenic. At follow-up, 13 (65%) of patients in the prehabilitation group had increased muscle mass versus 7 (35%) that experienced a decrease. Conversely, 16 (67%) controls experienced a decrease in muscle mass and 8 (33%) showed an increase. An adjusted linear regression model estimated a mean treatment difference in Total Psoas Index of 40.2mm2/m2 (95% CI - 3.4 to 83.7) between groups in change from baseline (p = 0.07). CONCLUSIONS: Prehabilitation improved muscle mass in patients with rectal cancer who had NACRT. These results need to be explored in a larger trial to determine if the poorer short- and long-term patient outcomes associated with low muscle mass can be minimised by prehabilitation.

The relationship between sarcopenia and survival at 1 year in patients having elective colorectal cancer surgery.

BACKGROUND: Colorectal cancer remains a common cause of cancer death in the UK, with surgery being the mainstay of treatment. An objective measurement of the suitability of each patient for surgery, and their risk-benefit calculation, would be of great utility. We postulate that sarcopenia (low muscle mass) could fulfil this role as a prognostic indicator. The aim of this study was to determine the relationship between sarcopenia and long-term outcomes in patients undergoing elective bowel resection for colorectal cancer. METHODS: One hundred and sixty-three consecutive patients who had elective curative colorectal resection for cancer were eligible for inclusion in the study. Psoas muscle mass was assessed on preoperative computed tomography scan at the level of the L3 vertebra and standardised for patient height (total psoas index, TPI). Sarcopenia (low muscle mass) was defined as < 524 mm2/m2 in males and 385 mm2/m2 in females. In addition to clinical-pathological parameters, postoperative complications were recorded and patients were followed up for mortality for 1 year after surgery. RESULTS: Sarcopenia was present in 19.6% of the study participants and was significantly related to body mass index (p = 0.007), 30-day mortality (p = 0.042) and 1-year mortality (p = 0.046). In univariate analysis, American Society of Anesthesiologists grade (p = 0.016), tumour stage (p = 0.018) and sarcopenia (p = 0.043) were found to be significant independent predictors of 1-year mortality. CONCLUSIONS: This study has found sarcopenia to be prevalent in patients with colorectal cancer having elective surgery. Independent of age, sarcopenia was associated with poorer 30-day mortality and survival at 1 year. Measurement of muscle mass preoperatively could be used to stratify a patient's risk, allowing targeted strategies such as prehabilitation, to be implemented to modify sarcopenia and improve long-term outcomes for patients.

Donegal Going against the Flow: National Differences in Long-Term Urinary Catheterisation Rates in Men (> 65 Years) With Benign Prostatic Hypertrophy.

An analysis of Primary Care Reimbursement Service (PCRS, 2013) data demonstrated high rates of urinary catheter changes in Donegal compared to other regions of Ireland. There is a catheter change rate of 10.2% in Donegal men over 65 with medical cards (GMS) compared to rates of 2.7% and 0.17% in Waterford and South Dublin, respectively1. This 60-fold difference between an area with perceived good access to services (South Dublin) and Donegal an area that does not, prompted a survey of general practitioners in each of these areas to assess whether true male catheterisation rates were similarly disproportionate in Donegal. Based on this, data was collected from a population of 23,794 GMS patients in GP training practices in Donegal (Rural), Leinster (Urban) and Waterford (Suburban). The data sampled for Donegal demonstrated 19 long-term catheters (LTCs per 8603 GMS) compared to four LTCs (per 5,800 GMS) in Leinster and 3 LTCs (per 9,391 GMS) in Waterford (Table 1). This anomaly in LTC rates may be a proxy for lack of access to basic Urology services.

Child abuse and fabricated or induced illness in the ENT setting: a systematic review.

BACKGROUND: Child maltreatment is persistently under-recognised. Given that a third of maltreated children may return with serious or fatal injuries, it is imperative that otolaryngologists who are in frequent contact with children are able to detect maltreatment at first presentation. OBJECTIVE OF REVIEW: This review aims to identify ENT injuries, signs or symptoms that are indicative of physical abuse or fabricated or induced illness (child maltreatment). TYPE OF REVIEW: Systematic review. SEARCH STRATEGY: An all-language search, developed in Medline Ovid and consisting of 76 key words, was conducted of published and grey literature across 10 databases from inception to July 2015, for primary observational studies involving children aged <18 years. EVALUATION METHOD: Each relevant article underwent two independent reviews with full critical appraisal, applying strict quality standards. RESULTS: Of the 2448 studies identified and screened, 371 underwent full review, resulting in 38 included studies that detailed 122 maltreated children. Pharyngeal perforations (n = 20) were the most frequent abusive ENT injury, predominantly affecting neonates and infants, presenting with dysphagia, drooling, haemoptysis and surgical emphysema. At least 52% of children with abusive pharyngeal injuries had additional co-existent injuries. The majority of ear injuries were inflicted to the external ear (n = 11) and included auricular deformity, abrasions, petechiae, lacerations and burns. Fabricated or induced illness cases presented most commonly with recurrent, unexplained otorrhoea or ENT lesions that failed to heal despite appropriate therapy. CONCLUSIONS: All clinicians should be familiar with the signs of child maltreatment. Pharyngeal injuries, or injuries to the external ear, presenting in young children without an explicit history of witnessed injury should prompt a child protection referral for full evaluation. Likewise, children who present with recurrent, or apparently intractable symptoms and signs despite appropriate treatment, should raise the possibility of fabricated or induced illness, and discussion with a child protection specialist is advised. Early recognition of possible child maltreatment and instigation of appropriate safeguarding measures are essential to prevent repetition and escalation of injury. This is of paramount importance to otolaryngologists, who have the potential to identify these children in their practice.

Robust anti-obesity and metabolic effects of a dual GLP-1/glucagon receptor peptide agonist in rodents and non-human primates.

AIMS: To characterize the pharmacology of MEDI0382, a peptide dual agonist of glucagon-like peptide-1 (GLP-1) and glucagon receptors. MATERIALS AND METHODS: MEDI0382 was evaluated in vitro for its ability to stimulate cAMP accumulation in cell lines expressing transfected recombinant or endogenous GLP-1 or glucagon receptors, to potentiate glucose-stimulated insulin secretion (GSIS) in pancreatic ß-cell lines and stimulate hepatic glucose output (HGO) by primary hepatocytes. The ability of MEDI0382 to reduce body weight and improve energy balance (i.e. food intake and energy expenditure), as well as control blood glucose, was evaluated in mouse models of obesity and healthy cynomolgus monkeys following single and repeated daily subcutaneous administration for up to 2 months. RESULTS: MEDI0382 potently activated rodent, cynomolgus and human GLP-1 and glucagon receptors and exhibited a fivefold bias for activation of GLP-1 receptor versus the glucagon receptor. MEDI0382 produced superior weight loss and comparable glucose lowering to the GLP-1 peptide analogue liraglutide when administered daily at comparable doses in DIO mice. The additional fat mass reduction elicited by MEDI0382 probably results from a glucagon receptor-mediated increase in energy expenditure, whereas food intake suppression results from activation of the GLP-1 receptor. Notably, the significant weight loss elicited by MEDI0382 in DIO mice was recapitulated in cynomolgus monkeys. CONCLUSIONS: Repeated administration of MEDI0382 elicits profound weight loss in DIO mice and non-human primates, produces robust glucose control and reduces hepatic fat content and fasting insulin and glucose levels. The balance of activities at the GLP-1 and glucagon receptors is considered to be optimal for achieving weight and glucose control in overweight or obese Type 2 diabetic patients.

Traumatic central cord syndrome: neurological and functional outcome at 3 years.

STUDY DESIGN: Retrospective cohort analysis with prospective follow-up. OBJECTIVES: To evaluate neurological and functional recovery following central cord syndrome. SETTING: Northern Ireland, population 1.8 million. METHODS: Twenty-seven cords were identified in 1 year. Five managed conservatively and 22 with surgery. American Spinal Injury Association (ASIA) motor scores (AMS) were calculated to assess neurological recovery. Rotterdam scores assessed functional independence at 3 years. RESULTS: Average age was 62 years. Mechanism of injury was a fall with neck hyperextension in 81% patients. Average AMS in surgical patients improved from injury, preoperatively, postoperatively, 6 months and 3 years from 51, 81, 83, 90 to 96, respectively. Conservative patients improved from time of injury to day 10 from 57 to 86 and then fell to 84 at 6 months. By 3 years, this had recovered to 91. There was no statistical significant difference in AMS (P=0.15)/change in AMS (ΔAMS) (P=0.92) or percentage of motor deficit resolution (P=0.23) between groups at 3 years. Two patients underwent surgery within 48 h and achieved full motor recovery by 3 years, but this was not significant (P=0.2). ASIA score improvement had a positive correlation with age at injury. Patients treated with surgery had better Rotterdam scores at 3 years than those managed conservatively (P=0.05). CONCLUSIONS: This study confirms the natural history of central cord syndrome. Although it demonstrates equivocal neurological recovery for both groups, patients treated with surgery regained a greater degree of functional independence.

Isolated anterior mediastinal tuberculosis in an immunocompetent patient.

BACKGROUND: The differential diagnosis of a mediastinal mass is a common challenge in clinical practice, with a wide range of differential diagnosis to be considered. One of the rarer causes is tuberculosis. Atypical presentations of tuberculosis are well documented in immunocompromised patients, but should also be considered in the immunocompetent. CASE PRESENTATION: This case outlines a previously healthy 22 year-old immunocompetent male presenting with worsening chest pain, positional dyspnea, dry cough and dysphagia. Chest x-ray showed evidence of an isolated anterior mediastinal mass, which was confirmed on computed tomography. A mediastinoscopy was diagnostic as histology revealed necrotizing granulomatous inflammation and the presence of acid-fast bacilli, indicating mediastinal tuberculosis. CONCLUSION: Typically the underlying presentation of mediastinal tuberculosis is mediastinal lymphadenitis. This case was unusual in that we detected an isolated large anterior mediastinal mass accompanied by a relatively small burden of mediastinal lymphadenitis. Cases similar to this have been documented in immunosuppressed patients however in our case no evidence of immunosuppression was found. This case report emphasizes the importance that a detailed and logical pathway of investigation is pursued when encountering a mediastinal mass.

Listeria meningitis complicating a patient with ulcerative colitis on concomitant infliximab and hydrocortisone.

Infliximab, a monoclonal antibody directed against tumour necrosis factor, is an effective therapy for moderate-to-severe ulcerative colitis and Crohn's disease. Uncommonly, serious opportunistic infections have occurred in patients after infliximab administration. Here, we describe meningitis caused by Listeria monocytogenes developing in a 37-year-old man with ulcerative colitis refractory to intravenous corticosteroids 10 days after receiving his first infusion of infliximab. With the increasing use of tumour necrosis factor-α-neutralizing agents, clinicians should be aware of the risk of opportunistic infections caused by L. monocytogenes in patients with inflammatory bowel disease following infliximab treatment. The half-life of infliximab is 9.5 days; therefore, patients tend to be more susceptible in the immediate period following infusion. Patients receiving anti-TNF therapy should be advised to avoid foods such as soft cheeses and unpasteurized dairy products.

Assessment of clinical occupational dose reduction effect of a new interventional cardiology shield for radial access combined with a scatter reducing drape.

OBJECTIVES: To assess the occupational dose reduction effect of a new interventional cardiology shield for radial access combined with a scatter reducing drape. BACKGROUND: Transradial access for catheterization has been shown to increase occupational radiation dose. Current shielding techniques are primarily based on the femoral access. This article looks at the clinical occupational combined dose reduction effect of a commercially available shield and drape which is specific to access type. METHODS: The evaluation took place in a busy interventional cardiology laboratory, with a single plane 30×40 cm flat panel detector (Siemens Artis Zee, Germany). Radiation exposure to staff was measured using electronic personal dosimeters (Unfors RaysafeAB, Sweden) placed at the collar. Patient radiation exposure was assessed using screening time and dose area product per case. Both staff and patient radiation exposure were monitored for a number of case types and operators before, during, and after deployment of the new shield and drapes. RESULTS: The cardiologists' overall median collar badge reading per case reduced from 15.4 µSv per case without the shield/drape combination to 7.3 µSv per case with the shield drape combination in situ (P<0.001). The radiographers badge reading was reduced from 4.2 µSv per case without to 2.5 µSv per case with the shield drape combination in situ (P<0.001). There was no statistical difference in the cardiac technician's badge reading. Patient's dose area product was not significantly affected by the placement of the shield and drape combination. CONCLUSIONS: The shield/drape combination can significantly reduce operator exposure in a cardiac catheterization laboratory.

A systematic review of abusive visceral injuries in childhood--their range and recognition.

OBJECTIVES: To define what abusive visceral injuries occur, including their clinical features and the value of screening tests for abdominal injury among abused children. METHODS: We searched 12 databases, with snowballing techniques, for the period 1950-2011, with all identified studies undergoing two independent reviews by trained reviewers, drawn from pediatrics, radiology, pediatric surgery and pathology. Of 5802 studies identified, 188 were reviewed. We included studies of children aged 0-18, with confirmed abusive etiology, whose injury was defined by computed tomography, contrast studies or at surgery/post mortem. We excluded injuries due to sexual abuse, or those exclusively addressing management or outcome. RESULTS: Of 88 included studies (64 addressing abdominal injuries), only five were comparative. Every organ in the body has been injured, intra-thoracic injuries were commoner in those aged less than five years. Children with abusive abdominal injuries were younger (2.5-3.7 years vs. 7.6-10.3 years) than accidentally injured children. Duodenal injuries were commonly recorded in abused children, particularly involving the third or fourth part, and were not reported in accidentally injured children less than four years old. Liver and pancreatic injuries were frequently recorded, with potential pancreatic pseudocyst formation. Abdominal bruising was absent in up to 80% of those with abdominal injuries, and co-existent injuries included fractures, burns and head injury. Post mortem studies revealed that a number of the children had sustained previous, unrecognized, abdominal injuries. The mortality from abusive abdominal injuries was significantly higher than accidental injuries (53% vs. 21%). Only three studies addressed screening for abdominal injury among abused children, and were unsuitable for meta-analysis due to lack of standardized investigations, in particular those with 'negative' screening tests were not consistently investigated. CONCLUSIONS: Visceral injuries may affect any organ of the body, predominantly abdominal viscera. A non-motor vehicle related duodenal trauma in a child aged

In search of Pinkel's children: unravelling the biological heterogeneity of childhood acute lymphoblastic leukaemia by genotype and treatment molecular response.

BACKGROUND: Acute lymphoblastic leukaemia (ALL), the commonest childhood malignancy has seen remarkable progress since the 1960s with cure rates now approaching 85%. To achieve this patients undergo intensive treatment that usually takes 2.5-3.5 years involving on average 15 different chemotherapeutic drugs. In 1971, Donald Pinkel reported Total Therapy-Protocol V that used 5 drugs and cranial radiation therapy over a similar time period. Today, one half of these patients (Pinkel's children) remain alive and free of leukaemia. AIM: The aim of this study was to evaluate the impact post-induction minimal residual disease (MRD) levels had on survival and its relationship with the more established clinical and biological prognostic predictors of outcome in the hope of identifying a subgroup of patients that are at very low risk of failure. METHODS: A retrospective review of 250 Irish children with ALL was carried out. MRD status after 28 days of induction chemotherapy and other known predictors of outcome were correlated with 5 year event-free survival (EFS). RESULTS: MRD status was the strongest predictor of outcome with 5 year EFS rates greater that 90% seen in those patients with low-risk MRD and this was associated with TEL/AML1 rearrangement, high hyperdiploidy (HH) karyotype and female gender. CONCLUSION: Both MRD and karyotype are powerful determinants of outcome in childhood ALL. Therefore, it is reasonable to conclude that the majority of children cured by Pinkel et al. in the late 1960s were most likely composed of low-risk MRD, TEL/AML1 and HH patients.

Catheter policies for management of long term voiding problems in adults with neurogenic bladder disorders.

BACKGROUND: Management of the neurogenic bladder has the primary objectives of maintaining continence, ensuring low bladder pressure (to avoid renal damage) and avoiding or minimising infection. Options include intermittent urethral catheterisation, indwelling urethral or suprapubic catheterisation, timed voiding, use of external catheter (for men), drug treatment, augmentation cystoplasty and urinary diversion. OBJECTIVES: To assess the effects of using different types of urinary catheters and external (sheath) catheters in managing the neurogenic bladder, compared to alternative management strategies or interventions. SEARCH STRATEGY: We searched the Cochrane Incontinence Group specialised register (searched 11 June 2003). We sought additional trials from other sources such as reference lists of relevant articles and contacting consultants in Spinal Cord Injury Centres throughout the United Kingdom. SELECTION CRITERIA: All randomised and quasi-randomised controlled trials comparing methods of using catheters to manage urinary voiding in people with neurogenic bladder. DATA COLLECTION AND ANALYSIS: Abstracts were independently inspected by the reviewers and full papers were obtained where necessary. MAIN RESULTS: Approximately 400 studies were scrutinised. No trials were found that met the inclusion criteria, and five studies were excluded from the review. REVIEWERS' CONCLUSIONS: Despite a comprehensive search no evidence from randomised or quasi-randomised controlled trials was found. It was not possible to draw any conclusions regarding the use of different types of catheter in managing the neurogenic bladder.

Adult human olfactory stem cells.

The location of stem cells within the adult CNS makes them impractical for surgical removal and autologous transplantation. Their limited availability and histocompatibility issues further restrict their use. In contrast, olfactory neuroepithelium (ONe) located in the nasal passageways has a continuous regenerative capability and can be biopsied readily. To investigate the potential of human ONe to provide viable populations of pluripotent cells, ONe was harvested from cadavers 6-18 h postmortem, dissociated, plated and fed every 3-4 days. Heterogeneous populations of neurons, glia, and epithelia were identified with lineage-specific markers. After several weeks, 5-10% of the cultures produced a population of rapidly dividing cells, which in turn, produced neurospheres containing at least two subpopulations based on neuronal and glial specific antigens. Most contained one or more neuronal markers; a few were positive for A2B5 and/or GFAP. To determine if growth modulators would affect the neurosphere forming cells, they were exposed to dibutyryl-cAMP. The nucleotide reduced cell division and increased process formation. Although the cells had been passaged more than 70 times, their viability remained constant as shown by the MTT viability index. Donor age or sex were not limiting factors, because neurospheres have been established from cadavers of both sexes from 50 to 95 years old at time of death. The ex vivo expansion of these cells will provide a patient-specific population of cells for immunological, genetic and pharmacological evaluation. Our long-term goal is to determine the utility of these cells to facilitate CNS repair.

Combining serial analysis of gene expression and array technologies to identify genes differentially expressed in breast cancer.

Several methods have been used recently to determine gene expression profiles of cell populations. Here we demonstrate the strength of combining two approaches, serial analysis of gene expression (SAGE) and DNA arrays, to help elucidate pathways in breast cancer progression by finding genes consistently expressed at different levels in primary breast cancers, metastatic breast cancers, and normal mammary epithelial cells. SAGE profiles of 21PT and 21MT, two well-characterized breast tumor cell lines, were compared with SAGE profiles of normal breast epithelial cells to identify differentially expressed genes. A subset of these candidates was then placed on an array and screened with clinical breast tumor samples to find genes and expressed sequence tags that are consistently expressed at different levels in diseased and normal tissues. In addition to finding the predicted overexpression of known breast cancer markers HER-2/neu and MUC-1, the powerful coupling of SAGE and DNA arrays resulted in the identification of genes and potential pathways not implicated previously in breast cancer. Moreover, these techniques also generated information about the differences and similarities of expression profiles in primary and metastatic breast tumors. Thus, combining SAGE and custom array technology allowed for the rapid identification and validation of the clinical relevance of many genes potentially involved in breast cancer progression. These differentially expressed genes may be useful as tumor markers and prognostic indicators and may be suitable targets for various forms of therapeutic intervention.

A human DAZ transgene confers partial rescue of the mouse Dazl null phenotype.

In a subset of infertile men, a spectrum of spermatogenic defects ranging from a complete absence of germ cells (sertoli cell only) to oligozoospermia is associated with microdeletions of the DAZ (deleted in azoospermia) gene cluster on human distal Yq. DAZ encodes a testis-specific protein with RNA-binding potential recently derived from a single-copy gene DAZL1 (DAZ-like) on chromosome 3. Y chromosomal DAZ homologues are confined to humans and higher primates. It remains unclear which function unique to higher primate spermatogenesis DAZ may serve, and the functional status of the gene recently has been questioned. To assess the extent of functional conservation we have tested the capacity of a human DAZ gene contained in a 225-kb yeast artificial chromosome to complement the sterile phenotype of the Dazl null mouse (Dazl-/-), which is characterized by severe germ-cell depletion and meiotic failure. Although Dazl-/- mice remained infertile when the DAZ transgene was introduced, histological examination revealed a partial and variable rescue of the mutant phenotype, manifest as a pronounced increase in the germ cell population of the seminiferous tubules and survival to the pachytene stage of meiosis. As well as constituting definitive proof of the spermatogenic role of the DAZ gene product, these findings confirm the high degree of functional conservation between the DAZ and DAZL1 genes, suggesting they may constitute a single target for contraceptive intervention and raising the possibility of therapeutic up-regulation of the DAZL1 gene in infertile men.

Primary squamous cell carcinoma of the parotid gland: the importance of correct histological diagnosis.

BACKGROUND: Primary squamous cell carcinoma of the parotid is an uncommon, aggressive malignancy with a poor prognosis. The diagnosis is made after excluding metastasis from other sites in the head and neck or other primary malignancies of the parotid. METHODS: Tumor registry data from 1974 to 1994 were reviewed at three University of Louisville-affiliated hospitals. Of 370 parotid tumors, 40 (11%) were initially classified as squamous cell carcinoma of the parotid. Chart review and histological specimen re-examination were conducted to confirm diagnosis. RESULTS: Only 8 (2%) of the 370 cases, were considered true primary squamous cell carcinoma of the parotid. Patients with metastases to the parotid from primary sites within the upper aerodigestive tract or skin of the head and neck region and high-grade mucoepidermoid carcinoma of the parotid were excluded. Facial nerve dysfunction was a presenting complaint in three patients. Two patients presented with American Joint Committee on Cancer (AJC) clinical stage III disease and six with AJC stage IV disease. All patients were treated with total parotidectomy and radiotherapy. One patient (12%) is alive and free of disease. Median survival was 13 months (range, 11 months-7 years). CONCLUSIONS: Primary squamous cell carcinoma of the parotid is uncommon, occurring in 2% of parotid neoplasms at our institution. This is an aggressive malignancy, usually presenting in advanced stage and with facial nerve involvement or cervical metastases. Prognosis is poor even with radical surgery and adjunctive radiotherapy. Careful clinical and histological review is necessary to differentiate primary squamous cancer of the parotid from metastases or other primary parotid malignancy.

Expression of oestrogen receptor beta (ER beta) in multiple rat tissues visualised by immunohistochemistry.

Steroid hormones regulate cell function via specific receptors, members of a super family of ligand activated transcription factors, expressed in their target tissues. A second oestrogen receptor (ER beta) has recently been shown by RT-PCR to have a wide tissue distribution distinct from that of oestrogen receptor alpha (ER alpha). We have raised a polyclonal antiserum using a peptide specific for ER beta in order to determine the cellular sites of expression of the receptor. In the adult rat ER beta was localised to cell nuclei in a wide range of tissues including ovary, oviduct, uterus, lung, adrenal, seminal vesicle, bladder, heart, prostate and testis. In the ovary ER beta was present in multiple cell types including granulosa cells in small, medium and large follicles, theca and corpora lutea whereas ER alpha was undetectable in these cell types. In the uterus ER beta and ER alpha were both present in epithelial cells lining the lumen and glands. In the lung ER beta was present in the cells lining the bronchioles and alveoli as well as in smooth muscle. In bladder and seminal vesicle immunostaining was intense in epithelial cells but the receptor was also expressed in nuclei of smooth muscle cells. Cell nuclei of the heart ventricle were immunopositive for ER beta as were most cells of the adult rat adrenal. In the seminiferous epithelium of the testis, nuclei of Sertoli cells were immunopositive but expression was not stage dependent. In conclusion, immunohistochemistry has proved invaluable in visualising specific sites of expression of ER beta in complex tissues including those of the reproductive tract.