Isolation and characterization of the notch ligand delta4

Notch signaling plays a critical role in a variety of developmental programs. In vertebrates, the complexity of the process is underscored by the existence of multiple Notch receptors and multiple ligands, each of which displays a distinct expression profile. Furthermore, the ligands can be subdivided into two families, the Serrate/Jagged family and the Delta family. Here we present the isolation of a novel Notch ligand, Delta4. Expression analyses indicate that mouse Delta4 is highly expressed in the eye and lung during embryogenesis and in the heart, lung, liver, and kidney of the adult. Functionally, Delta4 is indistinguishable from Jagged1 in its abilities to inhibit myogenesis and to stimulate transcription through Notch1 and the DNA binding protein CSL.

Structural genomics in the biotechnology sector

Commercial efforts in structural genomics focus on providing to pharmaceutical customers information that relates to the suitability of specific proteins as drug targets and the informed selection and refinement of lead compounds generated by high-throughput screening and rational approaches. These efforts follow a variety of business models and are impacted by activities in the public domain, recent technological advances, and the changing intellectual property landscape.

Telangiectatic dedifferentiation of a parosteal osteosarcoma

A unique case of parosteal osteosarcoma (POS) of the proximal femur, with areas of telangiectatic dedifferentiation, in a 28-year-old woman is reported. The patient had a 7-week history of pain and swelling in her right thigh. A biopsy diagnosis of POS was established. The patient was treated with two cycles of intraarterial chemotherapy, followed by limb salvage surgery. Histological examination of the resected specimen showed POS with areas of dedifferentiation composed of highgrade telangiectatic osteosarcoma with associated secondary aneurysmal bone cyst change.

A randomized controlled trial of Moderation-Oriented Cue Exposure

OBJECTIVE

A randomized controlled trial was conducted to examine the effectiveness of Moderation-Oriented Cue Exposure (MOCE) in comparison to Behavioral Self-Control Training (BSCT). The main hypothesis was that MOCE would be more effective than BSCT among a sample of problem drinkers aiming at moderate drinking. A subsidiary hypothesis was that MOCE would be relatively more effective than BSCT among problem drinkers with higher levels of alcohol dependence.

METHOD

Clients (N = 91; 75% men) were randomly allocated to either MOCE or BSCT. Treatment was delivered in weekly sessions by two trained therapists, in a nested design in which therapists switched to the alternative treatment modality approximately halfway through the trial. Follow-up was carried out 6 months following posttreatment assessment, with 85% successful contact.

RESULTS

There was no evidence for the general superiority of MOCE over BSCT. The subsidiary hypothesis was not confirmed. A subsample of clients (n = 14) showing levels of dependence at baseline above the commonly accepted cut-point for a moderation goal (Severity of Alcohol Dependence Questionnaire [SADQ] > 29) showed outcomes at least as favorable as those below the cut-point. The validity of self-reports of alcohol consumption and problems was supported by significant relationships with liver function tests (gamma-glutamyl transferase and alanine transferase).

CONCLUSIONS

These results provide no grounds for the replacement of BSCT by MOCE in routine, moderation-oriented treatment practice. Assuming they prefer it to abstinence and that it is not contra-indicated on other grounds, there seems no reason why clients showing a higher level of dependence (SADQ = 30-45) should not be offered a moderation goal.

Interaction of exogenous DNA with the nuclear matrix of live spermatozoa

Sperm chromatin is a highly organized array of protamines and DNA, with the protamines serving to tightly condense the DNA into a compact, defined structure. We have previously demonstrated that the sperm nucleus is an ordered library of DNA organized into functional zones, such as the nuclear matrix and nuclear annulus. Other laboratories have suggested that mouse spermatozoa can interact with exogenous pSV2CAT plasmid DNA. In this work, we explored this interaction and examined the subcellular localization of the exogenous DNA. We found a repeatable association of exogenous DNA with a specific region of the sperm nuclear matrix. This region of the nucleus correlates with the equatorial segment of the sperm head. This interaction requires only a defined fertilization media, transfection quality DNA, and incubation with spermatozoa.

Risk behaviours for HIV and hepatitis infection among anabolic-androgenic steroid users

This study examined HIV and hepatitis risk behaviours among anabolic-androgenic steroid (AAS) users and controls, providing a detailed assessment of both injection and sexual practices. Fifty AAS-using and 40 non-AAS-using weight trainers completed a semi-structured interview followed by a detailed questionnaire. The 'high risk' behaviour of sharing needles and syringes was not current practice among the AAS-using sample, with only one user reporting sharing injecting equipment in the past. However, for some users it was common practice to share multi-dose vials (19%) and to divide drugs using syringes (17%). Both these practices are potential routes for HIV and hepatitis infection. Significantly more AAS users (36%) reported increases in sex drive over the last three months than did the control subjects (5%). More AAS users than controls were engaging in sex with more than one partner while infrequently using condoms. These findings support the maintenance of needle exchange schemes which are essential to continued safe injecting practices among AAS users. The elevated sexual risk behaviour of AAS users could be due to AAS's effect of increasing sex drive or to a 'risk taking' personality trait among AAS users.

Hyperphosphorylated tau and neurofilament and cytoskeletal disruptions in mice overexpressing human p25, an activator of cdk5

Hyperphosphorylation of microtubule-associated proteins such as tau and neurofilament may underlie the cytoskeletal abnormalities and neuronal death seen in several neurodegenerative diseases including Alzheimer's disease. One potential mechanism of microtubule-associated protein hyperphosphorylation is augmented activity of protein kinases known to associate with microtubules, such as cdk5 or GSK3beta. Here we show that tau and neurofilament are hyperphosphorylated in transgenic mice that overexpress human p25, an activator of cdk5. The p25 transgenic mice display silver-positive neurons using the Bielschowsky stain. Disturbances in neuronal cytoskeletal organization are apparent at the ultrastructural level. These changes are localized predominantly to the amygdala, thalamus/hypothalamus, and cortex. The p25 transgenic mice display increased spontaneous locomotor activity and differences from control in the elevated plus-maze test. The overexpression of an activator of cdk5 in transgenic mice results in increased cdk5 activity that is sufficient to produce hyperphosphorylation of tau and neurofilament as well as cytoskeletal disruptions reminiscent of Alzheimer's disease and other neurodegenerative diseases.

Total-body echo-planar MR imaging in the staging of breast cancer: comparison with conventional methods--early experience

PURPOSE

To test breast cancer staging with total-body echo-planar magnetic resonance (MR) imaging.

MATERIALS AND METHODS

Nineteen patients with newly diagnosed breast cancer were imaged by using a 1.5-T echo-planar MR system. By using a table sweep method, 180 contiguous axial images were obtained from the cranial vertex through the feet with T2-weighted spin-echo and inversion-recovery sequences. Results were compared with those of conventional imaging. Therapeutic decisions based on echo-planar MR imaging and conventional imaging results were compared. Diagnostic truth was determined by means of tissue diagnosis, further imaging findings, and follow-up findings (median, 18 months).

RESULTS

Staging with total-body echo-planar MR imaging was correct in 18 patients (95%)--eight with metastases and 10 without--while staging with conventional imaging was correct in 15 patients (79%). In one patient, both echo-planar MR imaging and conventional imaging findings incorrectly indicated probable metastases. In one patient thought to have bone metastases at conventional imaging, echo-planar MR imaging findings were normal, which was correct. Two patients with stage IV disease were not suspected to have disease at conventional imaging: One had liver involvement and the other had skeletal metastases. The therapeutic decisions in these two patients were altered by the echo-planar MR imaging results.

CONCLUSION

Total-body echo-planar MR imaging was at least as accurate as conventional imaging for staging newly diagnosed breast cancer and was faster, simpler, and completely noninvasive.

Further investigations on the hydrolytic degradation of poly (DL-lactide)

The hydrolytic degradation of poly(DL-lactide) (PLA50) material was investigated in order to elucidate the effects of temperature and acidity of the external medium on the degradation characteristics. It was observed that at 60 degrees C and at pH = 7.4, degradation was extremely rapid as compared with degradation at 37 degrees C. After only 2 days, heterogeneous degradation was observed due to larger internal autocatalysis. On the other hand, in the case of degradation at 37 degrees C in an acidic medium with pH = 3.7, the heterogeneous degradation was preceded by a much longer lag time. Water absorption was found to be pH dependent. At pH = 7.4, water absorption was increased due to the osmotic pressure driving the buffer solution into the polymer matrix to neutralize acidic endgroups, which was not the case for degradation at pH = 3.7. In both cases, the oligomeric stereocomplex was obtained as degradation residue at the end of the degradation period.

Recommendations for the reporting of tissues removed as part of the surgical treatment of cutaneous melanoma. The Association of Directors of Anatomic and Surgical Pathology

The Association of Directors of Anatomic and Surgical Pathology has developed recommendations for the surgical pathology report for common malignant tumors. The recommendations for cutaneous melanoma are reported.

Intrusive memories and depression in cancer patients

Matched samples of depressed and nondepressed cancer patients were interviewed about past life events, particularly experiences of death and illness. They identified and described any spontaneous intrusive visual memories they had experienced in the past week corresponding to these events. About one quarter reported such memories and, as predicted, the majority of intrusive memories concerned illness, injury and death. The mean levels of intrusion and avoidance were equivalent to patients with post-traumatic stress disorder. Consistent with prediction, depressed patients reported significantly more intrusive memories than controls, and described the memories as typically beginning with or being exacerbated by the onset of depression. Greater numbers of intrusive memories were associated with more maladaptive coping, and greater avoidance with deficits in autobiographical memory functioning.

Cystic adenomyosis of the uterus: MRI

Adenomyosis of the uterus is most often seen as focal or diffuse thickening of the myometrial junctional zone on MRI. We describe the morphologic features and signal characteristics of the rarer cystic form of the disease, as revealed by MRI. We conclude that cystic adenomyosis of the uterus is characterized by a well-circumscribed cystic lesion within the myometrium that demonstrates hemorrhage in differential stages of organization on MR images.

Spitz nevus versus spitzoid malignant melanoma: an evaluation of the current distinguishing histopathologic criteria

Because of the well-known difficulty in distinguishing between Spitz nevi and spitzoid malignant melanomas at the microscopic level, the critical importance of this task notwithstanding, expert dermatopathologists across the world have strenuously endeavored to identify histopathologic criteria that would assist microscopists in this effort. Many reports itemizing such criteria are extant. The objective of the current study was to determine which of these criteria serve as the most consistent discriminators. Using a population of 11 spitzoid melanomas and 12 Spitz nevi, we evaluated six sets of criteria purported to be helpful in differentiating between these entities. Overall, we found that six features had significant distinguishing capacity, namely, (1) Kamino bodies, (2) a brisk mitotic rate, (3) mitoses close to the base of the lesion, (4) abnormal mitoses, (5) symmetry, and (6) uniformity of nests from side to side. It is noteworthy that the first three of these rank among the six criteria itemized repeatedly in 50% or more of the sets of criteria evaluated.

Does pelvic magnetic resonance imaging differentiate among the histologic subtypes of uterine leiomyomata?

OBJECTIVE

To evaluate if pelvic magnetic resonance imaging (MRI) is reliable for differentiating leiomyoma subtypes.

DESIGN

Prospective study.

SETTING

Academic center.

PATIENT(S)

Forty-five patients underwent MRI before surgery for leiomyomata.

INTERVENTION(S)

One radiologist blinded to patient history and histologic diagnosis recorded the MRI characteristics and classification of the largest leiomyoma.

MAIN OUTCOME MEASURE(S)

Comparison of MRI and histologic diagnoses.

RESULT(S)

Leiomyoma subtypes were diagnosed accurately by MRI in 69% of cases. Magnetic resonance imaging had a 95% sensitivity and 72% specificity for diagnosing an uncomplicated leiomyoma and a 10% sensitivity and 100% specificity for a cellular leiomyoma. For cystic leiomyomata, the sensitivity was 80% and specificity was 98%, and for hemorrhagic leiomyomata, 100% and 86%, respectively. Magnetic resonance imaging correctly diagnosed all malignant tumors and did not incorrectly diagnose a leiomyoma as a leiomyosarcoma in any case. Ill-defined MRI margins were significantly more likely to be leiomyosarcoma, whereas well-defined margins were characteristic of benign lesions. Hemorrhagic leiomyomata were significantly more likely to be hyperintense on T1-weighted images than other subtypes.

CONCLUSION(S)

Although MRI is only fairly accurate in differentiating the subtypes of benign uterine smooth muscle tumors, signal intensities and margin characteristics are useful to distinguish accurately benign from malignant tumors.

A phase I and pharmacokinetic study of LY231514, the multitargeted antifolate

LY231514 is a novel antifolate that principally inhibits thymidylate synthase, but with additional folate-dependent enzyme targets. A Phase I study of single-agent LY231514 administered as a daily i.v. infusion over 10 minutes for 5 days, repeated every 3 weeks, was conducted to evaluate the maximum tolerated dose, pharmacokinetic profile, and antitumor activity of the drug using this schedule. Thirty-eight patients with advanced malignancies that were refractory or not amenable to standard therapy were treated with a total of 116 courses of LY231514, escalating treatment doses through 10 dose levels, from 0.2-5.2 mg/m2/day. No objective clinical responses were observed, although minor antitumor activity not fulfilling the response criteria was seen in three patients. A maximum tolerated dose of 4.0 mg/m2/day was determined, with neutropenia as the predominant dose-limiting toxicity. Reversible disturbances of liver biochemistry, fulfilling the protocol definitions of dose-limiting toxicity, were also observed. Other toxicities included diarrhea, mucositis, skin rash, and fatigue. Pharmacokinetic studies were performed at all treatment levels. Analysis showed a linear relation between administered dose and both maximum plasma concentration (Cmax) and area under the plasma concentration/time curve. The drug was cleared with a day 1 total body clearance of 108.9 +/- 38.8 ml/min/m2, with plasma concentrations declining with a mean harmonic terminal half-life of 1.4 +/- 0.98 h. When given by this schedule, LY231514 is tolerable, and Phase II studies are in progress.

Memory processes and the course of anxiety and depression in cancer patients

BACKGROUND

Intrusive memories of stressful events, many involving illness and death, are found in a minority of depressed cancer patients, and may predict the course of anxiety and depression.

METHOD

Matched samples of mild to moderately depressed and non-depressed cancer patients were followed up after 6 months. Anxiety and depression at follow-up were related to measures of intrusive memories of stressful life events and autobiographical memory functioning that had been assessed at baseline.

RESULTS

Levels of anxiety and depression remained fairly constant over time in the two groups, and the depressed group continued to experience high levels of intrusive memories. The presence of intrusive memories at baseline, and the extent to which these memories were consciously avoided, predicted greater anxiety at follow-up, even after controlling for initial severity of physical and psychiatric symptoms. None of the measures of memory functioning predicted levels of depression at follow-up.

CONCLUSIONS

Intrusive memories appear to be a marker of more prolonged psychopathology in cancer patients and may respond to direct therapeutic intervention.

Ethics of fertility treatment

This article is the second in our series looking at issues surrounding fertility treatment. It outlines the role of the Human Fertilisation and Embryology Authority in regulation and in protecting the public.

Fibroma and fibrothecoma of the ovary: MR imaging findings

PURPOSE

To describe the morphologic and signal intensity characteristics on magnetic resonance (MR) images of fibromas and fibrothecomas.

MATERIALS AND METHODS

MR images of 11 female patients with histologically proved fibromas or fibrothecomas were reviewed, and morphologic and signal intensity characteristics of the lesions were analyzed. MR imaging findings were correlated with histologic findings.

RESULTS

All fibromas and fibrothecomas showed homogeneous low signal intensity on T1-weighted images. On T2-weighted images, the two smallest lesions showed homogeneous low signal intensity, and eight of the other nine lesions showed predominantly low signal intensity. Edema was noted only in larger lesions, and cystic degeneration was noted only in three of the largest lesions. On T2-weighted images, the percentage of low signal intensity in the lesion was not found to be related to lesion size, and the percentage of low signal intensity in fibromas was not significantly different from that in fibrothecomas (P = .55). Many lesions showed heterogeneous signal intensity; the solid component was distributed peripherally, and the cystic component was located centrally or eccentrically. Free intraperitoneal fluid was noted in 10 of 11 lesions and was not significantly correlated with lesion size (r = .52 and P = .10).

CONCLUSION

Because of their predominantly low signal intensity on T2-weighted images, fibromas and fibrothecomas display a relatively specific appearance on MR images.

Autosomal dominant polycystic kidney disease: pathophysiology and treatment

Once viewed as a hopelessly incurable disease, autosomal dominant polycystic kidney disease (ADPKD) has been given a great deal of attention as geneticists search for ADPKD genes, and cell biologists are studying and understanding cyst formation. Alterations in cellular growth, secretion, and extracellular matrix all participate in cystogenesis. ADPKD is one of the most common hereditary diseases in the United States and is a frequent cause of chronic renal failure. The disease is a systemic disorder that may affect multiple organ systems. Manifestations of ADPKD in renal and extrarenal systems may be challenging problems in the management of these patients. Although no therapy is available, treatment of the complications is highly effective in most cases in supportive management of the disease.

Do triage nurse-initiated X-rays for limb injuries reduce patient transit time?

Patients with isolated limb injuries are often required to wait a long time for treatment and investigation in emergency departments. It was hypothesized that allowing triage nurses to initiate X-rays would reduce transit times for these patients. A prospective, randomized comparison trial of 175 patients was conducted, comparing transit times between a group of patients who had X-rays initiated at triage and a group which did not. No statistically significant reduction in transit time was demonstrated by this change in practice, either for a group who had sustained fractures or for one which had not. Despite this finding, staff and patient satisfaction with this change in procedure was high. This justifies continuation of the practice and further research.

Conspicuity of normal and pathologic female pelvic anatomy: comparison of gadolinium-enhanced T1-weighted images and fast spin echo T2-weighted images

PURPOSE

Our goal was to compare the conspicuity of normal and pathologic female pelvic anatomy between gadolinium-enhanced T1-weighted images and fast SE (FSE) T2-weighted images.

METHOD

In 48 consecutive female patients, pre- and postenhanced T1-weighted images were compared with FSE T2-weighted images acquired with a phased array coil. Normal zonal anatomy (ZA) and pathologic abnormalities in gadolinium-enhanced T1-weighted images were rated as increased, decreased, or without change in conspicuity as compared with FSE T2-weighted images.

RESULTS

The normal ZA of the uterine corpus on T1-weighted images showed a decrease in conspicuity in 93% of patients and an increase in 7% compared with FSE T2-weighted images. Conspicuity of cervical ZA on T1-weighted images was decreased in 86%, increased in 6%, and without change in 8% as compared with FSE T2-weighted images. ZA of the vagina on T1-weighted images was decreased in 94% and increased in 6% as compared with FSE T2-weighted images. On T1-weighted images, ovarian anatomy delineation was decreased in 95% and increased in 5% as compared with FSE T2-weighted images. Conspicuity of malignant pathologic abnormalities on T1-weighted images was decreased in 81%, increased in 11%, and without change in 8% as compared with FSE T2-weighted images. In patients with benign disease, conspicuity on T1-weighted images was decreased in 92%, increased in none, and without change in 8% as compared with FSE T2-weighted images. The p value for all categories was < 0.0001.

CONCLUSION

Conspicuity of both normal and pathologic anatomy was significantly decreased on enhanced T1-weighted images. The use of gadolinium cannot replace T2-weighted scans for delineation of anatomy and disease and should be reserved to cases in which standard imaging sequences are not sufficiently diagnostic.

Acute ureteral obstruction: value of secondary signs of helical unenhanced CT

OBJECTIVE

The purpose of our study was to determine the value of secondary signs of ureteral obstruction on helical unenhanced CT.

MATERIALS AND METHODS

Over a 19-month interval, 312 patients with acute flank pain were imaged with helical unenhanced CT. Ureteral stone disease was confirmed to be present in 109 patients and confirmed to be absent in 111 patients Ninety-two remaining patients had no confirmatory imaging studies or surgery and were unable to be contacted for follow-up. For each of the 220 patients with a confirmed diagnosis, we determined the presence or absence of ureteral or collecting system dilatation, perinephric stranding, symmetry of renal size, and renal stones. In all patients with a ureteral stone, we noted the presence or absence of a circumferential rim of soft-tissue attenuation ("tissue-rim" sign) surrounding each stone and each phlebolith.

RESULTS

The sensitivity of each secondary sign was ureteral dilatation, 90%; perinephric stranding, 82%; collecting system dilatation, 83%; and renal enlargement, 71%. The specificity of each secondary sign was ureteral dilatation, 93%; perinephric stranding, 93%; collecting system dilatation, 94%; and renal enlargement, 89%. Ureteral dilatation and perinephric stranding were both present or both absent in 181 of the 220 patients with a confirmed diagnosis. In this subgroup, this combination of signs had a positive predictive value of 99% and a negative predictive value of 95%. The odds ratio for the frequency of the tissue-rim sign with stones versus tissue-rim with phleboliths was 31:1.

CONCLUSION

When using unenhanced CT to help diagnose acute flank pain, if one does not see a ureteral stone or does see an indeterminate but suspicious calcification, then secondary signs of obstruction are important for diagnosis. The results of this study form the basis of an imaging algorithm that can be used when interpreting unenhanced CT images of patients with acute flank pain.

Bizarre parosteal osteochondromatous proliferation: a review of seven cases

BACKGROUND

Bizarre parosteal osteochondromatous proliferation (BPOP) is a rare tumour-like condition mostly affecting the tubular bones of the hands and feet. Although it recurs in 50% of cases after local excision, it is a form of heterotopic ossification and its behaviour is otherwise benign. The present study describes seven cases of BPOP collected by the Bone Tumour Registry of New South Wales.

METHODS

Clinical data, radiographs and histological specimens collected by the Bone Tumour Registry of New South Wales were examined, and further clinical data were sought from the referring doctor where necessary.

RESULTS

Six males and one female aged 18 to 37 years (median 30 years) presented between 1988 and 1995. There were three cases involving the hands, three involving the feet and one involving the distal humerus. Initial treatment was by local excision in all cases. There was local recurrence in three cases. The initial diagnosis was wrong in five of the seven cases. Radiologically, BPOP appears as a well-defined tumour arising directly from the bony cortex, without periosteal reaction or change to the underlying bone. Histologically, a large amount of hypercellular cartilage shows maturation to trabecular bone, which frequently contains spindle cells in the intertrabecular spaces.

CONCLUSION

BPOP is a rare, locally recurrent but otherwise benign condition of bone which must be distinguished from more sinister lesions such as parosteal osteosarcoma and chondrosarcoma.