Asymptomatic grade-2 central chondrosarcoma of the distal femur with non-aggressive radiological features.

This paper discusses the case of a 57-year-old man with an incidental finding of a radiologically non-aggressive chondroid lesion and concomitant osteonecrosis in the left distal femur. The final resected specimen showed a grade-2 chondrosarcoma. This case illustrates that long-term follow-up is necessary for non-aggressive chondroid lesions. If surgical management is considered, resection with an adequate margin is superior to intralesional curettage.

A sarcoma of 23 years' duration: symptom duration is not a reliable parameter to exclude malignancy.

This report describes a 31-year-old woman with a 23-year history of a right buttock mass that was otherwise asymptomatic, but was proven to be a low-grade fibromyxoid sarcoma (a fully malignant soft tissue tumour with a potential for distant metastasis). This case illustrates that a long-standing tumour does not necessarily imply a benign pathology. A vigilant approach should be taken for any tumours that are of significant size (larger than 5 cm).

Resting and anergic B cells are defective in CD28-dependent costimulation of naive CD4+ T cells.

Successful antibody production in vivo depends on a number of cellular events, one of the most important of these being cognate B cell-T cell interaction. To examine this phenomenon in vitro, homogeneous populations of hen egg lysozyme (HEL)-specific small resting B cells and naive CD4+ HEL-specific T cells (derived from immunoglobulin [Ig] and T cell receptor transgenic mice, respectively) were cultured together. On addition of intact HEL protein. HEL-specific B cells increase their expression of activation molecules, including a B7-related protein and CD44, and enlarge into blast cells. Within the same cultures, HEL-specific CD4+ T cells also increase expression of the activation markers CD69 and CD44, enlarge, secrete lymphokines, and proliferate. This response is radiation sensitive, supporting the conclusion that HEL-specific B cells present antigen to and activate the naive T cells. By contrast, when a synthetic peptide fragment of HEL is used to bypass B cell antigen-receptor engagement, the naive T cells enlarge and display activation antigens, but fail to produce lymphokines, proliferate, or promote B cell blastogenesis. Presentation of HEL by tolerant B cells, which are no longer able to signal effectively through their antigen receptors, results in an identical pattern of incomplete T cell activation. Addition of a stimulating anti-CD28 antibody and blocking of CD28 signals with CTLA4/Ig fusion protein both show that complete activation of naive CD4+ T cells depends on the initial induction of B7 and related costimulatory molecules after HEL binding to nontolerant HEL-specific B cells. Thus, in the absence of adequate constimulation from the B cell, naive CD4+ T cells undergo a form of "partial activation" in which they upregulate surface expression of certain T cell activation antigens, but fail to efficiently produce lymphokine and proliferate. This may explain the different conclusions that have been reached regarding the consequences of B cell antigen presentation to T cells, in that the ability of B cells to activate naive CD4+ T cells depends both on their specificity and their activation state.

Neuroimaging techniques in epilepsy.

OBJECTIVE: To review state-of-the-art neuroimaging modalities in epilepsy and their clinical applications. DATA SOURCES AND STUDY SELECTION: PubMed literature searches to March 2010, using the following key words: 'epilepsy', 'positron emission tomography (PET)', 'single photon emission computed tomography (SPECT)', 'MR volumetry', 'diffusion tensor imaging', and 'functional MR imaging'. DATA EXTRACTION: All articles including neuroimaging techniques in epilepsy were included in the review. DATA SYNTHESIS: High-field magnetic resonance imaging is fundamental for high-resolution structural imaging. Functional radionuclide imaging (positron emission tomography/single-photon emission computed tomography) can provide additional information to improve overall accuracy, and show good results with high concordance rates in temporal lobe epilepsy. Magnetic resonance spectroscopy is a useful adjunct consistently demonstrating changing metabolites in the epileptogenic region. Magnetic resonance volumetric imaging shows excellent sensitivity and specificity for temporal lobe epilepsy but thus far it has been inconsistent for extratemporal epilepsy. Diffusion tensor imaging with tractography allows visualisation of specific tracts such as connections with the language and visual cortex to enhance preoperative evaluation. Functional magnetic resonance imaging using blood oxygen level-dependent activation techniques is mainly used in presurgical planning for the high-sensitivity mapping of the eloquent cortex. Both contrast-bolus and arterial spin labelling magnetic resonance perfusion imaging show good correlation with clinical lateralisation of seizure disorder. CONCLUSION: Structural imaging is essential in localisation and lateralisation of the seizure focus. Functional radionuclide imaging or advanced magnetic resonance imaging techniques can provide complementary information when an epileptogenic substrate is not identified or in the presence of non-concordant clinical and structural findings.

Dedifferentiated endometrioid adenocarcinoma of the uterus: A case series and review of literature.

Introduction Dedifferentiated endometrioid adenocarcinoma (DEAC) was first described in 2007. However, it has only been recognised as a distinct subtype of endometrioid adenocarcinoma in the last 1-2 years. DEAC is a more aggressive histological subtype and carries a poorer prognosis. Patients with DEAC tend to present with advanced disease compared the other endometrioid adenocarcinomas. Methodology The study is a retrospective review of patients with DEAC diagnosed in two institutions in Singapore between January 2012 and October 2017. Results 7 patients were diagnosed with DEAC. The mean age was 56.4 years. All patients presented with either abnormal uterine bleeding or post menopausal bleeding. Out of the 7 patients, one was diagnosed with Stage 2 disease, 5 were diagnosed with Stage 3 disease and 1 was diagnosed with Stage 4 disease. One patient had neoadjuvant chemotherapy, followed by surgery, and completion chemotherapy post surgery. The other 6 patients (87.5%) underwent primary debulking surgery. Out of these 6 patients, 5 patients had adjuvant chemotherapy post surgery and one patient had both adjuvant chemotherapy and radiotherapy. Lymphovascular invasion was found in 71.4% of the cases. Conclusion DEAC is a more aggressive histological subtype of endometrioid adenocarcinomas. Better awareness of this condition can lead to proper diagnosis and treatment.

Characteristics and photocatalytic activity of TiO2 thin film sensitized with a porphyrin dye.

In this study, a novel porphyrin dye, 5, 10, 15, 20-tetraphenyl-21H, 23H-porphine nickel (TPPN) doped TiO2 (TiO2/TPPN) thin film with visible light respondency was prepared using a sol-gel method and characterized with XRD, SEM, UV-Vis instruments. The observation showed that the absorption edge of TPPN dye-doped thin film shifted into the visible light region. The photocatalytic indigo carmine degradation results showed that under visible light irradiation (lambda > 400 nm) for 6 hrs, the photocatalytic activity of TiO2 thin film sensitized with 200 microM of TPPN dye showed the best performance, with an indigo degradation ratio up to 96%. Moreover, the TiO2/TPPN thin film showed a relevant photocatalytic bactericidal effect on Erwinia carotovora subsp. carotovora 7 induced vegetable soft rot disease in the visible spectral region. Evidence for the photocatalytic disinfection technique against a plant pathogen under visible light irradiation will have potential for direct application in future control of plant diseases in irrigation water systems.

Modulatory effects of endogenous adenosine on epinephrine secretion from the adrenal medulla of the rat.

The purpose of this study was to examine (1) whether endogenous adenosine receptors inhibit the release of epinephrine and norepinephrine from adrenal medulla in response to physiological and pharmacological stimuli and (2) whether the renin-angiotensin system modulates this effect of endogenous adenosine. We used a conscious animal model to approximate normal physiological conditions. Male Sprague-Dawley rats were treated with a surface adenosine receptor antagonist, 1,3-dipropyl- 8-(p-sulfophenyl)xanthine (DPSPX) to explore the effect of endogenous adenosine. Plasma epinephrine and norepinephrine levels in response to hydralazine-induced hypotension were measured in these animals. The same protocol was repeated in rats pretreated with either adrenalectomy or captopril. The results showed that DPSPX treatment significantly increased plasma epinephrine and norepinephrine levels at both baseline conditions and after hydralazine-induced hypotension. The results from the adrenalectomized rats showed that the difference in plasma epinephrine level between the control and DPSPX groups originated from the adrenal medulla. Pretreatment with captopril attenuated the rise of plasma epinephrine and norepinephrine levels in DPSPX-treated animals. This result suggests that endogenous adenosine receptors inhibit epinephrine release from the adrenal medulla and suppress plasma norepinephrine levels. When catecholamine release was stimulated by physiological and pharmacological stimuli, this inhibitory function of adenosine receptors was augmented. The renin-angiotensin system is at least partially responsible for the modulatory function of endogenous adenosine on the catecholamine response as demonstrated in this study.

Patient effective dose from sentinel lymph node lymphoscintigraphy in breast cancer: a study using a female humanoid phantom and thermoluminescent dosemeters.

The aim of this study was to measure the dose delivered to patients undergoing sentinel lymph node lymphoscintigraphy by taking into account both the transmission scan dose using a (57)Co flood source and the (99)Tc(m) internal emission dose. An adult female humanoid phantom and a set of thermoluminescent dosimeters were used in the measurements. The choice of measurement organs in the humanoid was guided by the recommendations described in the International Commission on Radiological Protection report number 60. A (57)Co flood source was used in external transmission to irradiate the humanoid at posterior, left lateral, left posterior oblique, right lateral and right posterior oblique positions. Four (99)Tc(m) deposits as internal emission sources were used to simulate patient peritumoural injection. The individual effective doses for external transmission and internal emission, normalized to the cumulated activity and expressed in micro Sv(MBq x h)(-1) were then calculated. The effective dose for a transmission scan was on average 0.061 micro Sv(MBq x h)(-1) for each (57)Co flood source position and for internal emission 0.312 micro Sv(MBq x h)(-1) and 0.291 micro Sv(MBq x h)(-1) for left and right breast injection, respectively. Using these results, the effective dose from both transmission and emission sources can be calculated according to the nuclear medicine scanning protocol and surgical procedure of the individual institution. For our protocols, the patient receives a maximum effective dose of 52 micro Sv for the 1 day protocol (18 MBq injection) and 204 micro Sv for the 2 day protocol (74 MBq injection) if only the sentinel lymph node is excised. If other tissues containing radioactivity are removed, the patient effective dose will be reduced by about 50% and 6%, respectively, for the 1 day protocol and 2 day protocol. Although the doses are low compared with other radiological examinations, the results are informative for patients concerned about radiation exposure for this new imaging technique.

Sacral and pubic insufficiency fractures after irradiation of gynaecological malignancies.

The association between radiotherapy and insufficiency fractures of the pelvis has not been well documented. Fractures were detected over a 2-year period in eight postmenopausal women who had previously undergone irradiation for gynaecological malignancies. Six of these patients also had local soft tissue complications, such as rectal bleeding and haematuria, in addition to severe low back, buttock or groin pain, caused by the fractures. Plain radiographs were unhelpful in the detection of sacral insufficiency fractures, but showed the pubic fractures in five patients. Diagnoses of insufficiency fractures were made on bone scintigraphic demonstration of the typical 'H' shaped sacral pattern, or the combination of the partial 'H' pattern together with public uptake. Computed tomography was useful for confirmation of insufficiency fractures in doubtful cases. Recognition of insufficiency fractures helps to avoid the pitfalls of misdiagnosing tumour recurrence or bony metastases.

Applications of bone scintigraphy in ankylosing spondylitis.

Eighteen bone scintisans performed in 14 patients with ankylosing spondylitis were reviewed. In young patients with low back pain, positive serology, and indeterminate radiographs, quantitative sacroiliac joint assessment and the presence of typical uptake patterns, particularly costovertebral, were useful in suggesting the diagnosis. Scintigraphy was helpful in the early detection of pseudoarthrosis complicating long-standing disease, especially in patients presenting with recurrent back pain. Selective application of bone scintigraphy aids the diagnosis of ankylosing spondylitis and its potential complications.

Sacral insufficiency fractures. Spectrum of radiological features.

Clinical and radiological features of 22 Chinese patients with sacral insufficiency fractures were reviewed. Twenty-one were postmenopausal women. Other risk factors were external pelvic radiotherapy (eight) and total hip replacement (two). Severe low back pain was the most common presenting complaint. Fractures initially were demonstrated by bone scintigraphy in 21 and computed tomography (CT) in seven patients. Concomitant parasymphyseal and pubic rami fractures were detected in 17 and 10 patients, respectively. Follow-up assessment by CT and bone scintigraphy in five patients showed various stages of fracture healing. Recognition of the radiological patterns of this entity is emphasized.

Thromboelastographic study of thrombosis in the implantable central venous access device.

BACKGROUND: In the present study thromboelastography (TEG) was to study whether or not hypercoagulopathy might contribute to the thrombosis of implantable central venous access device (Port-A-Cath, Pharmacia) in cancer patients. METHODS: All 76 oncological patients who were enrolled in this study had their R time, alpha angle and MA value measured before Port-A-Cath implantation, of whom 11 patients received re-implantation because of thrombotic device. We compared the measurements of these 11 patients (thrombotic group) with that of 65 patients (control group) who received Port-A-Cath implantation for the first time. According to TEG values the hemostatic status in these patients was classified as hypercoagulable, normal or hypocoagulable for comparison. All patients in the control group were followed up for 3 months for occurrence of thrombosis. RESULTS: It was found that no patient in the thrombotic group was associated with hypercoagulopathy. Five patients (7.5%) in the control group was found in hypercoagulable status at the time of catheter insertion but none of them developed clinical thrombosis during three months of observation. There was no significant difference between the two groups for R time, alpha angle but a higher MA value was found in the control group (p < 0.05). Furthermore, the hypercoagulability (7.5% for the control vs. none for the thrombotic group), hypocoagulability (1.5% vs. 9.1%) and normocoagulability (91.0% vs. 90.9%) were not statistically different between the two groups (Fisher exact test, P = 0.229). CONCLUSIONS: We conclude that hypercoagulopathy in cancer patients has little, if any, contribution in thrombosis of the implantable central venous access device.

Involvement of two distinct signalling pathways in IGF-1-mediated central control of hypotensive effects in normotensive and hypertensive rats.

AIMS: Insulin-like growth factor-1 (IGF-1) is abundantly expressed in the nucleus tractus solitarii (NTS). In a previous study, we revealed that the induction of nitric oxide (NO) production in the NTS reduces blood pressure (BP). It is well known that both acute administration and chronic administration of IGF-I reduce BP. The aim of this study was to evaluate the short-term hypotensive effect of IGF-1 in the NTS and to delineate the underlying molecular mechanisms of IGF-1 in the NTS of normotensive WKY rats and spontaneously hypertensive rats (SHRs). METHOD: Microinjections of the phosphatidylinositol 3-kinase (PI3K) inhibitor LY294002 and the MAP kinase-ERK kinase (MEK) inhibitor PD98059 into the NTS in WKY rats and SHRs were used to study the involvement of IGF-1-induced depressor effects. RESULT: An IGF-1 (7.7 pmol) injection into the NTS resulted in a significant decrease in BP and HR in WKY rats and SHRs. Immunoblotting and immunohistochemical analysis showed that the microinjection of LY294002 (0.6 pmol) or PD98059 (3.0 pmol) into the NTS attenuated the IGF-1-induced depressor effects and Akt or ERK phosphorylation in WKY rats. An attenuation effect of LY294002, but not PD98059, was found in the SHRs. However, the mRNA and protein expression levels of the IGF-1R showed no significant differences in the NTS of the WKY rats and the SHRs. CONCLUSION: These results suggest that distinct Akt and ERK signalling pathways mediated the IGF-1 control of the central depressor effects in WKY rats and SHRs. ERK signalling defects may be associated with the development of hypertension.

Prognostic factors associated with clear cell sarcoma in 14 Chinese patients.

PURPOSE. To identify prognostic factors associated with clear cell sarcomas in 14 Chinese patients. METHODS. Medical records of 7 men and 7 women (mean age, 36 years) with histologically confirmed clear cell sarcoma of tendons and aponeuroses were reviewed. Patient demographics, tumour characteristics, and treatment modalities were retrieved. Prognostic factors associated with favourable 5-year survival were determined. RESULTS. The most affected sites were the thigh (n=5) and the foot (n=4); the mean time from symptom onset to diagnosis was 9.5 months. The tumour stage at diagnosis was IIA in 8 patients, IIB in 2, and III in 4. The mean tumour size was 4.5 cm in diameter. One patient was lost to follow-up. For the remaining 13 patients, the mean time to disease-related mortality was 2.5 years. Nine patients had distant metastases; the most common sites were lungs and pleura (n=7), followed by distant lymph nodes (n=4), bone (n=2), pericardium (n=2), and brain (n=1). All patients underwent surgical excision. Three women and one man (mean age, 27 years) attained 5-year disease-free survival. All had stage IIA tumours at diagnosis. Their mean tumour size was 1.75 cm in diameter, which was significantly smaller than that of all patients (4.5 cm). Tumour size of ≤ 2.5 cm in diameter (p=0.004) and stage IIA tumour at diagnosis (p=0.04) were significant prognostic factors for 5-year survival. CONCLUSION. Tumour size of ≤ 2.5 cm and early stage tumour are associated with 5-year disease-free survival. Early detection is crucial for the prognosis of clear cell sarcomas.

In-vitro stability of beta-lactam antibiotics to hydrolysis by beta-lactamases of Neisseria gonorrhoeae from Southeast Asia.

Extracts of penicillinase-producing strains of Neisseria gonorrhoeae obtained from several localities in Southeast Asia exhibited similar patterns of relative rates of hydrolysis of benzylpenicillin, ampicillin, carbenicillin, and cephaloridine. Methicillin and oxacillin were not hydrolyzed. The isoelectric point of the beta-lactamase from these strains was 5.38 +/- 0.05, and the molecular weight was approximately 22.5. These properties, as well as the Km values determined for a range of substrates, were the same for the enzyme purified from one of the strains. These observations are consistent with those reported for other gonococcal beta-lactamases of the TEM-1 type. Cefamandole and to a lesser extent, cefoperazone, were also hydrolyzed by these extracts; however, the newer beta-lactam antibiotics piperacillin, cefuroxime, cefoxitin, ceftriaxone, ceftazidime, and moxalactam were stable. These stable compounds had little inhibitory effect on the activity of the enzyme toward benzylpenicillin or cephaloridine.

Insufficiency fractures of the sacrum and os pubis.

Insufficiency fractures are increasingly seen among postmenopausal women. Sacral fractures are difficult to detect clinically and radiographically, while os pubis fractures may mimic malignancy. Diagnosis is made by bone scintigraphy, supplemented by computed tomography. As patients respond well to conservative management, increased awareness and use of appropriate imaging may avoid unnecessary and invasive investigations.

Adenovirus terminal protein mediates both nuclear matrix association and efficient transcription of adenovirus DNA.

Adenovirus DNA is tightly bound to the nuclear matrix throughout the course of infection. Analysis of adenovirus DNA from infected HeLa cell nuclei after extraction with lithium diiodosalicylate and digestion with restriction enzymes demonstrated that the sites of tightest attachment occur in the terminal fragments of the linear viral chromosome. Analysis of viruses mutated in the precursor terminal protein coding sequence demonstrated that the terminal protein, which is covalently attached to the 5' end of each DNA strand, mediates the tight binding. Virions containing chromosomes with mutant terminal proteins were unpackaged and viral DNA accumulated in the nucleus at a normal rate and competed for the limiting component during transcription complex formation, but their early genes were transcribed at reduced efficiency by both RNA polymerases II and III. The transcriptional defects were not complemented by coinfection with a wild-type virus. We propose that the adenovirus chromosome may exist as a single chromatin domain during infection and that binding of DNA to the nuclear matrix may play a critical role in adenovirus transcription.

A five-year longitudinal study of the regional cerebral metabolic changes of a schizophrenic patient from the first episode using Tc-99m HMPAO SPECT.

This is a naturalistic study of the relationship between cerebral metabolic activity, clinical symptoms and treatment response in a schizophrenic patient for 5 years from the onset of her illness. Serial technetium-99m-HMPAO brain SPECT was used to measure regional cerebral metabolism. The Cambridge Neurological Inventory and neuropsychological tests (WAIS-R verbal subscales, Wisconsin Card Sorting Test, semantic verbal fluency, logical memory in Weschler Memory Scale) were used for neurocognitive assessment. Under-activity of the left temporal area was observed in the course of patient illness despite remission of the psychotic symptoms. Bilateral prefrontal metabolic under-activity was noted at the emergence of negative symptoms, executive neurocognitive dysfunction and the treatment-resistant state. After response to clozapine, the right prefrontal activity returned to a normal level. Our findings suggested that persistent left temporal underactivity detected by SPECT despite clinical remission may indicate a vulnerability for further relapses and development of a treatment-resistant state. Treatment-resistant state, negative symptoms and executive neurocognitive deficit may involve abnormal prefrontal metabolic activity and can be alleviated in clozapine-responsive patients.