Ischemic stroke in a teenage girl with primary antiphospholipid antibody syndrome

The diagnosis of stroke in children and young adults can be difficult, and the causes of ischemic stroke often remains unexplained even after extensive evaluation. We present a 13-year-old girl who had two ischemic strokes within a period of 3 weeks. A carotid duplex study and magnetic resonance angiography confirmed total occlusion of the left internal carotid artery. Serum immunologic examination revealed a high titer of immunoglobulin G anticardiolipin antibody (45.7 GPL U/mL; normal range, 0-16.2 GPL U/mL). The patient received long-term anticoagulation treatment with warfarin 5 to 7.5 mg per day, and international normalized ratios were maintained between 2.4 and 4.0. She recovered completely 5 weeks after the first stroke and has been well during the 6 months of follow-up after the onset. This is the first reported case of childhood ischemic stroke secondary to primary antiphospholipid antibody syndrome in Taiwan. This case emphasizes the importance of evaluating antiphospholipid antibody levels in patients with unexplained ischemic strokes.

Lack of evidence of association of p21WAF1/CIP1 polymorphism with lung cancer susceptibility and prognosis in Taiwan

An association between the Arg allele of the p21WAF1/CIP1 codon 31 polymorphism and lung cancer has been reported. However, the genotype distribution of the p21 codon 31 polymorphism, as well as the association of this polymorphism with lung cancer risk and prognosis, remain undefined in the Taiwanese population. Therefore, we investigated the genotype distribution of the p21 codon 31 polymorphism in 155 lung cancer patients and 189 non-cancer controls. The genotype frequencies in the Taiwanese non-cancer controls were 0.51 (Ser) and 0.49 (Arg). Chi2 analysis indicated significant differences in Taiwanese genotype distribution of p21 from those reported for Swedes (P=0.001), Caucasians (P=0.001), Indians (P=0.001), and African-Americans (P=0.001). However, our data did not demonstrate an association of the Arg allele of the p21 polymorphism with lung cancer risk in Taiwan. Lung cancer patients with Ser/Arg and Arg/Arg genotypes were at a nonsignificant 1.15-fold increased risk of lung cancer when compared to individuals with the Ser/Ser genotype (95%CI, 0.70-1.86). In addition, although p21 is a downstream target of p53, we found no significant correlation of the p21 polymorphism with the p53 polymorphism and p53 gene mutation in lung cancer patients. We further investigated the association of the p21 polymorphism with prognosis in 154 lung cancer patients. Patients with the Ser/Ser genotype tended to have a poorer prognosis than those with the Ser/Arg and Arg/Arg genotypes (P=0.097, by the log rank test). Our data suggest that the p21 codon 31 polymorphism may not play a significant role in cancer susceptibility and the prognosis of lung cancer patients in Taiwan.

Clinicopathologic analysis of malignant melanoma in Taiwan

BACKGROUND

Malignant melanoma is the leading cause of death among skin cancers in western countries. However, the incidence, histologic subtypes, and tumor behaviors are quite different in Asians and people of color.

OBJECTIVE

Our purpose was to define the tumor behaviors and possible prognostic predictors of melanomas based on a Taiwanese patient population.

METHODS

From the 65 patients diagnosed with melanoma at Veterans General Hospital, Taichung, we analyzed mean age at onset, gender, histologic subtypes, tumor thickness, level of invasion, primary tumor locations, and metastatic sites. Univariate analysis and multivariate analyses for survival, according to clinical and histologic tumor behaviors, were performed by means of Cox proportional hazard model. Survival curves were plotted by Kaplan-Meier method.

RESULTS

Fifty-one cutaneous melanomas were identified and analyzed by both clinical behaviors and histology. Acral lentiginous melanoma was the most common type (54.9%), followed by nodular melanoma (29.4%), superficial spreading melanoma, and lentigo maligna melanoma. Univariate analysis for overall survival of melanoma revealed that age at onset older than 55 years, male gender, ulceration of tumor, and thicker tumor have the tendency to poorer prognosis, but without significant differences. The advanced stages (III and IV) and histologic subtypes other than acral lentiginous melanoma predicted a poorer survival with significant differences. Multivariate analysis demonstrated advanced stages, and histologic subtypes were the independent risk factors for poor prognosis.

CONCLUSION

We proposed that histologic subtypes other than acral lentiginous melanoma and advanced stages have a poorer prognosis with significant differences.

Pulmonary cryptococcosis: manifestations in the era of acquired immunodeficiency syndrome

To examine the clinical manifestations, treatment, and outcome of pulmonary cryptococcosis, we reviewed the medical records of all patients treated for Cryptococcus neoformans infection at our hospital from January 1988 through September 1998. Sixty-three patients were included in the analysis, 10 (16%) of whom had acquired immunodeficiency syndrome (AIDS). Thirty-four of the 53 non-AIDS patients, including 19 men and 15 women had pulmonary cryptococcosis, including 31 with isolated pulmonary cryptococcosis and three with disseminated disease. Of the 10 AIDS patients, seven presented with disseminated cryptococcosis (including one patient with lung involvement) and one had isolated cryptococcal lung disease. The age (mean +/- SD) of the 34 non-AIDS patients with pulmonary cryptococcosis was 52.1 +/- 15.2 years (range, 19-75 yr). Cough was the most common symptom (58%). Diabetes mellitus (12%) and malignancy (12%) were two major underlying diseases. Nodules and masses were the predominant manifestations of pulmonary cryptococcosis in non-AIDS patients (79%). The most frequently used diagnostic modality for pulmonary cryptococcosis was biopsy with/without aspiration under ultrasound guidance (56%). Antifungal therapy (20/34) was the most common treatment for non-AIDS patients, followed by surgical resections with antifungal therapy (9), surgical resections alone (3), and no treatment (2). Antifungal therapy and/or resection yielded excellent outcomes (total recovery, 27; improvement, 4). Of the 18 patients who underwent lumbar puncture, only two had positive cerebrospinal fluid (CSF) cultures for C. neoformans, both had symptoms and signs of increased intracranial pressure. There was no clinical evidence of meningitis in the other 32 patients. Our findings indicate that pulmonary cryptococcosis in non-AIDS patients tends to be a more localized and benign process than in AIDS patients. Ultrasound-guided lung biopsy or aspiration is an effective tool for diagnosis. CSF examination may not be mandatory as an initial routine procedure for pulmonary cryptococcosis in non-AIDS patients.

[Localization of SC35 in the nucleolus and nucleoplasm of the root meristematic cells of Vicia faba]

SC35 is a non-snRNP spliceosome component purified from mammalian cells by Fu and Maniatis in 1990. In vitro splicing assays showed that SC35 plays a key role in splicing site selection and ATP-dependent pre-spliceosome assembly. In the mammalian nucleus, SC35 has been localized to distinct and dynamic nuclear domains: immunofluorescence observations revealed the presence of SC35 in speckles distributed in various regions throughout the nucleoplasm, which, as identified with immunoelectron microscopy, correspond to the interchromatin granules (IGs) and perichromatin fibrils (PFs). However, there has been no report regarding the presence and distribution pattern of SC35 in higher plant nuclei. Engage in such studies will surely contribute to our understanding of RNA processing and the spatial organization or structure basis of this process in higher plant. In this article, we studied the distribution pattern of SC35 in the nucleus of the root meristematic cells of Vicia faba by immunoelectron microscopy. After immunolabeling with anti-SC35 mAb and protein A-colloidal gold, IGs and PFs in the nucleoplasm and dense fibrillar component (DFC) of the nucleolus were heavily labeled with gold particles, while only a few of the gold particles were found in fibrillar centers (FC) and nucleolar vacuoles (NV) of the nucleolus and the central domains of the condensed chromatin. Densities of gold particles in the areas of DFC and the area of IGs plus PFs were 65.89/microns 2 and 36.28/microns 2 respectively, much higher than that of the central domain of condensed chromatin and that of FC plus NV, which were only 5.90/microns 2 and 6.26/microns 2 respectively. This indicates that DFC of the nucleolus and the area of IGs plus PFs of the nucleoplasm are enriched with SC35 or SC35-like protein. The distribution pattern of SC35 or SC35-like protein in the nucleoplasm of Vicia faba is similar to that of the mammalian nuclei. To the authors' knowledge, it is a new finding that SC35 or SC35-like protein exists in the nucleolus.

Predictors of depression among Chinese family caregivers of Alzheimer patients

From April 1996 to January 1997, 74 Alzheimer disease (AD) patients and their caregivers were recruited for participation in a comprehensive assessment at the Veterans General Hospital-Taipei, a 2,198-bed tertiary care teaching hospital in Taipei, Taiwan. Diagnosis of AD was made according to criteria of the Diagnostic and Statistical Manual of Mental Disorders-III-R (DSM-III-R). All AD patients were tested with the Chinese version of Cognitive Abilities Screening Instrument (CASI). Their primary caregivers rated the patients using the Revised Memory and Behavior Problems Checklist (RMBPC), the short version of Geriatric Depression Scale (GDS-S), and obtained information about coping strategies using the Carer's Stress scale. The three subscale scores for memory-related problems, depression, and disruptive behavior were obtained from the RMBPC. Scores for three subscales for management of situations, meaning, and distress were obtained from the coping strategies' assessment. Depression was defined as a GDS-S score > or = 5. Among the 74 AD patients, 38 were men and 36 women. Their ages ranged from 47 to 90 years, with a mean age of 72.2 years (SD, 9.0). The CASI scores ranged from 1 to 88 (mean, 45.2; SD, 22.9). Thirty-three caregivers were men and 41 were women. Their age ranged from 20 to 85 years, with a mean age of 53.5 years (SD, 16.9). Twenty-six of the 74 caregivers (35.1%) were classified as depressed. The GDS-S scores of caregivers were correlated positively with the frequency of the use of a management of distress coping strategy and the frequency of the patients' disruptive behavior and were correlated negatively with the educational years of the caregivers.

Poorer prognosis in young patients with gastric cancer?

BACKGROUND/AIMS

Although the relationship between prognosis and age of patients with gastric cancer is controversial, a poorer prognosis in young patients has been suggested by most investigators. To further examine the hypothesis, a retrospective study was undertaken to analyze a large series of patients with gastric cancer in Taiwan.

METHODOLOGY

A total of 1,642 consecutive patients diagnosed with gastric cancer and receiving further management at one medical center from 1988 to 1993 were reviewed. The gender, TNM tumor stage, rate of curative resection and survival of the patients were compared in the young age group (< or = 39 years) and the old age group (> 39 years). Survival was estimated with the product-limit method and difference in survival was tested by the log-rank test. Multivariate analysis was done by the Cox proportional hazard model.

RESULTS

Among the 1,642 patients, 61 patients were in the young age group and 1,581 patients were in the old age group. There was no significant difference for the 2 groups of patients in the distribution of TNM stage (stage I: 20%; II: 8%; III: 13%; IV: 59% vs. 19%, 11%, 25% and 45% respectively, in the old age group, p = 0.098) and rate of curative resection (38% vs 51% in the old age group, p = 0.059). The overall 5-year survival showed no significant difference between the 2 groups (25% vs. 29% in the old). Subgroup analyses showed that survival after curative resection and survival without curative treatment (including palliative resection and no resection) also had no difference in the 2 groups. Multivariate analysis also showed that age was not an independent factor.

CONCLUSIONS

Although most reports suggested a dismal prognosis in young patients with gastric cancer, based on our findings, young patients (< or = 39 years) do not have a worse prognosis than older patients.

[Comparisons of home care utilization between insured and not-insured patients]

In the Andersen-Newman model, utilization of medical services behavior affected by the three factors of need, enabling, and predisposing. Many studies on medical services behavior adapting this model obtained the same results. Our study aimed to describe the difference of insured and non-insured patients using home care, to examine the factors that explain the long-term utilization of home care by using Andersen-Newman model, and to survey the expenditure on home care. Our study collected 486 cases by questionnaires through home interview from various home care units from Sep. 1 to Dec. 31 1994. The response rate was 68.1%. Chi-square and multiple regression tests from SAS computer program performed data analysis. Our results showed there was a significant difference in four months' utilization between insured and non-insured patients (2.38/month vs 1.72/month, p < 0.01). However, if the utilization number per month was less than two, no significance between the two groups was found. Regarding utilization behavior in home care, there were some differences among the need, enabling, and predisposing factors. Our findings demonstrated young patients, patients with chronic illness, and the Fukienese with families involving for care were willing to pay for home care despite the fact that they did not have full support from the family. The determining factors affecting long-term utilization of home care were the Fukienese, patients owning an independent house, patients with health insurance, and patients who lived in mid- or east-Taiwan. In addition, patients with an elevated number of utilizations per month and poor daily activity used home care. All dependent variables could explain 62.38% of variance. The results proposed to the authorities concerned, health institutions and medical professionals for reference in developing home care program.

Revised memory and behavior problems checklist in Taiwanese patients with Alzheimer's disease

The Revised Memory and Behavior Problems Checklist (RMBPC) is a 24-item caregiver report that measures observable behavioral and memory problems in dementia patients and their caregivers' reaction to these problems. The purpose of the present study was to evaluate the applicability of the RMBPC for use in Taiwanese patients with Alzheimer's disease (AD). The subjects included 76 AD patients (39 men and 37 women, mean age 72.3) and their caregivers (34 men and 42 women, mean age 53.5) who participated in a comprehensive assessment at the Veterans General Hospital-Taipei. The Chinese version of the Cognitive Abilities Screening Instrument was administered to the patients. Their caregivers rated the RMBPC and the short version of the Geriatric Depression Score (GDS). To assess the test-retest reliability, 30 caregivers rated a second RMBPC 3 days after the first evaluation. The mean score for the frequency rating on the RMBPC was 32.63 (SD = 12.44, range = 5-61) and the mean reaction score was 10.96 (SD = 11.53). The reaction score was significantly correlated with the GDS score (r = .363, p = .001). The Cronbach's alpha coefficients for frequency and reaction scores were .816 and .895 respectively. The test-retest reliabilities of total frequency and reaction scores were significantly correlated; overall correlations were .89 for frequency (p < .001) and .74 for reaction (p < .001). These findings suggest that the RMBPC be recommended as a reliable tool to assess behavioral and memory disturbance in Taiwanese AD patients.

Small cell lung carcinoma associated with paraneoplastic limbic encephalitis

Limbic encephalitis is an unusual presentation of paraneoplastic syndrome. We report a case of small cell lung carcinoma associated with limbic encephalitis. A 67-year-old man presented with convulsions, memory impairment, and neuropsychiatric disturbances as initial symptoms. Subsequently, small cell lung carcinoma was diagnosed by bronchoscopic biopsy. The cerebrospinal fluid studies, electroencephalography, and magnetic resonance imaging findings had distinctive features compatible with paraneoplastic limbic encephalitis. The neuropsychiatric symptoms improved significantly after six cycles of systemic chemotherapy and adjuvant radiotherapy, resulting in partial remission of the tumor. A follow-up computed tomography scan of the head showed no evidence of intracranial metastasis 7 months after the diagnosis of cancer. Limbic encephalitis may be an initial manifestation of lung cancer. Greater awareness for diagnosis and early treatment of the primary tumor offers the best chance for improvement in patients with lung cancer presenting with limbic encephalitis.

The caregiving burden scale among Chinese caregivers of Alzheimer patients

From April 1996 to January 1997, a total of 76 Alzheimer's disease (AD) patients and their caregivers were recruited for participation in a comprehensive assessment at the Veterans General Hospital-Taipei, a 2,198-bed tertiary-care teaching hospital in Taipei, Taiwan. The AD patients responded to the Chinese version of the Cognitive Abilities Screening Instrument. Primary caregivers rated the patients using the Symptom Check List-90 (SLC-90) and the Revised Memory and Behavior Problems Checklist and then rated themselves with the caregiving burden scale (CBS), coping strategies scale and the short version of the Geriatric Depression Score (GDS-S). The internal consistency of the CBS, as assessed by Cronbach's alpha, was 0.849. The correlations between the CBS, SCL-90 and GDS-S ranged from 0.435 to 0.698. The CBS scores increased with disease progression and were higher among spouse caregivers than adult children caregivers. Multiple-regression analysis revealed that caregivers with higher CBS scores were more likely to have lower education levels and to use the meaning subscales of coping strategies, and that these caregivers' patients had greater disruptive behavior and were older (R2 = 0.727, p = 0. 001). The current study establishes the reliability and validity of the Chinese version of the CBS for assessment of Chinese caregivers of AD patients.

Levodopa may improve orthostatic tremor: case report and trial of treatment

Primary orthostatic tremor is a regular fast lower limb tremor causing unsteadiness on standing. Treatment is generally unsatisfactory. A patient with primary orthostatic tremor who 9 years later developed levodopa responsive idiopathic Parkinson's disease is described. The patient exhibited the classic features of primary orthostatic tremor with relief of the tremor by walking or sitting while treated with levodopa. However, in the "off" state, when the benefits of levodopa disappeared, this orthostatic tremor was continuous and severely compromised the patient's gait. On the basis of this finding eight patients with primary orthostatic tremor were treated with levodopa. Five patients experienced benefit and elected to remain on long term treatment. This study is the first trial of therapy in primary orthostatic tremor and suggests that levodopa can lead to good symptomatic relief in this potentially disabling condition.

Impairment of EEG desynchronisation before and during movement and its relation to bradykinesia in Parkinson's disease

OBJECTIVE

It has been suggested that the basal ganglia act to release cortical elements from idling (alpha) rhythms so that they may become coherent in the gamma range, thereby binding together those distributed activities necessary for the effective selection and execution of a motor act. This hypothesis was tested in 10 patients with idiopathic Parkinson's disease.

METHODS

Surface EEG was recorded during self paced squeezing of the hand and elbow flexion performed separately, simultaneously, or sequentially. Recordings were made after overnight withdrawal of medication and, again, 1 hour after levodopa. The medication related improvement in EEG desynchronisation (in the 7.5-12.5 Hz band) over the 1 second before movement and during movement were separately correlated with the improvement in movement time for each electrode site. Correlation coefficients (r) > 0.632 were considered significant (p<0.05).

RESULTS

Improvement in premovement desynchronisation correlated with reduction in bradykinesia over the contralateral sensorimotor cortex and supplementary motor area in flexion and squeeze, respectively. However, when both movements were combined either simultaneously or sequentially, this correlation shifted anteriorly, to areas overlying prefrontal cortex. Improvement in EEG desynchronisation during movement only correlated with reduction in bradykinesia in two tasks. Correlation was seen over the supplementary motor area during flexion, and central prefrontal and ipsilateral premotor areas during simultaneous flex and squeeze.

CONCLUSIONS

The results are consistent with the idea that the basal ganglia liberate frontal cortex from idling rhythms, and that this effect is focused and specific in so far as it changes with the demands of the task. In particular, the effective selection and execution of more complex tasks is associated with changes over the prefrontal cortex.

Self-organizing tree-growing network for the classification of protein sequences

The self-organizing tree algorithm (SOTA) was recently introduced to construct phylogenetic trees from biological sequences, based on the principles of Kohonen's self-organizing maps and on Fritzke's growing cell structures. SOTA is designed in such a way that the generation of new nodes can be stopped when the sequences assigned to a node are already above a certain similarity threshold. In this way a phylogenetic tree resolved at a high taxonomic level can be obtained. This capability is especially useful to classify sets of diversified sequences. SOTA was originally designed to analyze pre-aligned sequences. It is now adapted to be able to analyze patterns associated to the frequency of residues along a sequence, such as protein dipeptide composition and other n-gram compositions. In this work we show that the algorithm applied to these data is able to not only successfully construct phylogenetic trees of protein families, such as cytochrome c, triosephophate isomerase, and hemoglobin alpha chains, but also classify very diversified sequence data sets, such as a mixture of interleukins and their receptors.

Acute movement disorders with bilateral basal ganglia lesions in uremia

Acute and subacute extrapyramidal movement disorders are rarely reported in uremic patients. We report three such cases with basal ganglia lesions. All three had advanced renal failure with high serum creatinine levels. One of the patients had a history of ischemic heart disease and acute pulmonary edema with hypoxemia. Another patient had experienced arterial hypotension during previous hemodialysis. The third had prominent metabolic acidosis. One of the patients developed generalized dyskinesias, whereas the other two developed gait disturbances. Neuroimaging studies in all three cases showed bilateral changes in the basal ganglia. The natural history was self-limiting with gradual improvement. Diminution of the basal ganglia lesions was demonstrated on follow-up imaging in two of the three cases. We conclude that acute or subacute movement disorders with bilateral basal ganglia lesions may occur in uremia. Hypoperfusion with global brain ischemia and selective vulnerability of the basal ganglia to uremic toxins may account for these lesions.

Prevalence and subtypes of dementia in a rural Chinese population

We conducted a single-stage community-based study of dementia on all registered residents > or =65 years in age in a rural Chinese community. Neurologists conducted semistructured interviews and examined all participants; they also interviewed family members in cases where dementia was suspected. The diagnosis was made by consensus according to the criteria of the Diagnostic and Statistical Manual of Mental Disorders, 3rd ed, revised (DSM-III-R). Among the 2,055 contacted individuals, 1,736 (84.5%) participated in the study and 44 ( 13 men and 31 women) were diagnosed as having dementia, including 35 (80%) with probable Alzheimer disease (AD) and 3 (7%) with vascular dementia (VsD). The rates of dementia were 0.5% for ages 65-74 years, 2.9% for ages 75-84 years, and 12.0% for ages 85-101 years. The overall rate was 2.5% for age > or =65 years. After controlling for age, neither a lack of formal education nor being a woman was a risk factor for dementia. At 2-year follow-up, 30 of the 44 demented participants had died, yielding a 2-year survival rate of 32%. The present results corroborated our previous findings of lower prevalence rates of dementia among the Chinese than among Western populations, and both genetic and sociocultural factors may have contributed to the low rates. The lack of neuroradiological imaging studies in the present study may have contributed to the finding of an unusually low rate of VsD.

Effects of a novel antitumor depsipeptide, FR901228, on human breast cancer cells

Human breast cancer MCF7 and MDA-MB231 cells were used to investigate the biological and molecular activities of a novel naturally occurring agent, FR901228 (FR), that possesses a potent antitumor activity against human and murine tumor cells. Investigation of the cytotoxicity of FR and induction of internucleosomal DNA degradation in FR-treated cultures revealed that FR induced apoptotic-like cell death of MCF7 and MDA-MB231 cells. In FR-treated apoptotic cultures, flow cytometry revealed that there was a significant decrease of cells in S phase of the cell cycle. In FR-treated cells there was an increased expression of p21Cip1 and phosphorylation of Bcl-2 as determined by Western immunoblotting, and a novel cytoplasmic kinase of 33 kDa, p33 kinase, as determined by the in-gel kinase assay using myelin basic protein (MBP) as a substrate. Increased expression of p21CiP1, phosphorylation of Bcl-2, and activation of p33 MBP kinase may play part of the key mechanism for FR-induced apoptosis.

New phylogenetic venues opened by a novel implementation of the DNAml algorithm

SUMMARY

This note describes the parallelization of a key biological application, such as the construction of phylogenetic trees, using the DNAml program. A careful run-time analysis allowed us to propose an efficient parallelization that scaled very well to large problem sizes.

AVAILABILITY

By anonymous ftp at ftp.ac.uma. es (/pub/ots/pDNAml) or from our web site http://www.cnb.uam. es/www/software/software_index.html

CONTACT

ots@ac.uma.es

Lung cancer in pregnancy: report of two cases

Lung cancer during pregnancy is rare, although the number of case reports has been increasing in recent years. Herein, we describe two cases of lung carcinoma complicating pregnancy with different presentations and outcomes, and review the relevant literature. The first case involved a 31-year-old patient with squamous cell carcinoma with multiple bone metastases. The initial symptoms were productive cough and dyspnea on exertion during the second trimester of pregnancy, to which the patient paid little attention. Chemoradiation was started 1 month postpartum, soon after the diagnosis was made, but with little response. She died at home several days after palliative radiotherapy. The second case involved a 34-year-old patient with poorly differentiated lung carcinoma with brain metastasis. Left hemiparesis had developed initially during the third trimester. She underwent excision of the metastatic brain tumor and received radiotherapy to the left lung tumor and brain. The patient is still alive after a follow-up period of more than 1 year. Delayed diagnosis may be the main problem in the management of lung cancer during pregnancy, because of misinterpretation of common respiratory symptoms and physicians' reluctance to use radiologic imaging studies owing to concerns over the safety of the fetus. Thus, we suggest chest radiographs with abdominal lead shielding for pregnant patients with protracted cough and hemoptysis. Treatment of unresectable lung cancer during pregnancy generally consisted of radiation therapy with or without chemotherapy in previous reports, but the optimal therapy is still unknown, owing to inadequate case numbers and insufficient follow-up data.

The absence of strand-specific repair for the DNA polymerase pol gene in Deinococcus radiodurans

Deinococcus radiodurans is characterized by its extreme resistance to ionizing radiation. Although Mn+2 was taken up by the cells at a high speed, the absorption of Mn+2 by the cells did not affect their survival rate when irradiated by UV light. However, the Mn-induced-cell-division (Mn-CD) cells do lose their resistance to UV radiation. This can be explained by the fact that the Mn-CD cells were less efficient to remove pyrimidine dimers on damaged DNA. We also found that there is no strand-specific repair of the pol gene in this organism.

Self-organizing tree growing network for classifying amino acids

A self-organizing tree growing neural network was applied to classify amino acids and amino acid exchange matrices.

AVAILABILITY

SOTA, is freely available by anonymous FTP or at http://www.cnb.uam.es/bioinfo/Software/so ta.

CONTACT

carazo@cnb.uam.es

Diagnosis of pulmonary arteriovenous malformations by colour Doppler ultrasound and amplitude ultrasound angiography

BACKGROUND

The clinical value of colour Doppler ultrasound and amplitude ultrasound angiography in the diagnosis and follow up of pulmonary arteriovenous malformations (PAVM) was investigated.

METHODS

Six consecutive patients suspected by clinical appearance and abnormal chest radiographic findings of having PAVM were included in the study. Ultrasonography was performed first by real time grey scale imaging then by colour Doppler imaging and amplitude ultrasound angiography in a random order. All were later proved by angiography to have PAVM.

RESULTS

The ultrasound study was successfully performed in all six patients. A total of eight lesions was detected. The real time grey scale image of PAVM revealed well defined hypoechoic subpleural nodules with strong posterior acoustic enhancement. Colour Doppler ultrasound of PAVM showed turbulent flow, manifest as an area of intense colour with high and mixed velocities (reticulated or mosaiclike pattern). Anatomical continuity was demonstrated in some PAVM. Amplitude ultrasound angiography can delineate a tangled vascular structure with a clear vessel wall and anatomical continuity as well as conventional angiography. Spectral wave analysis showed a relatively low impedance flow presenting with high peak systolic velocity (mean 44.4 cm/s) and relatively high diastolic velocity (mean 19.3 cm/s). The mean pulsatility index (PI) and resistive index (RI) were 1.80 and 0.49, respectively. In two patients who received embolotherapy the colour Doppler ultrasound scan obtained after the procedure showed that the previous focal areas of colour flow signals disappeared or diminished in size. This was compatible with the decrease in, or absence of, blood flow demonstrated by angiography after embolotherapy.

CONCLUSIONS

Combined colour Doppler ultrasound and amplitude ultrasound angiography are useful non-invasive techniques for diagnosis PAVM and provide an alternative approach to angiography in evaluating the efficacy of embolotherapy.

Negative regulation of IS2 transposition by the cyclic AMP (cAMP)-cAMP receptor protein complex

Three sequences similar to that of the consensus binding sequence of the cyclic AMP (cAMP)-cAMP receptor protein (CRP) complex were found in the major IS2 promoter region. Experiments were performed to determine whether the cAMP-CRP complex plays a role in the regulation of IS2 transposition. In the gel retardation assay, the cAMP-CRP complex was found to be able to bind the major IS2 promoter. A DNA footprinting assay confirmed that the cAMP-CRP complex binds to the sequences mentioned above. With an IS2 promoter-luciferase gene fusion construct, the cAMP-CRP complex was shown to inhibit transcription from the major IS2 promoter. IS2 was found to transpose at a frequency approximately 200-fold higher in an Escherichia coli host defective for CRP or adenyl cyclase than in a wild-type host. These results suggest that the cAMP-CRP complex is a negative regulator of IS2 transposition.

Spindle cell carcinoma of the lung: a clinicopathologic presentation of three cases

Three patients with spindle cell carcinoma located in the lower respiratory tract are presented, including cases of two monophasic and one biphasic tumor. On light microscopic examination, the spindle cell components of the tumors were histologically characterized by sheets of fusiform spindle cells that closely resembled a sarcoma. Keratin expression in the spindle cell components of these tumors, as shown by anti-cytokeratin antibody staining, demonstrated their epithelial nature. It is supposed that the spindle cell component displays a spectrum of phenotypes originating from epithelial cells with varying degrees of mesenchymal transformation. It is difficult to establish a diagnosis of this rare primary pulmonary malignancy prior to surgical intervention. A review of the literature allowed for a summary of the clinicopathologic characteristics of this tumor.