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PubMed2006

Semi-automatic classification of bird vocalizations using spectral peak tracks.

Automatic off-line classification and recognition of bird vocalizations has been a subject of interest to ornithologists and pattern detection researchers for many years. Several new applications, including bird vocalization classification for aircraft bird strike avoidance, will require real time classification in the presence of noise and other disturbances. The vocalizations of many common bird species can be represented using a sum-of-sinusoids model. An experiment using computer software to perform peak tracking of spectral analysis data demonstrates the usefulness of the sum-of-sinusoids model for rapid automatic recognition of isolated bird syllables. The technique derives a set of spectral features by time-variant analysis of the recorded bird vocalizations, then performs a calculation of the degree to which the derived parameters match a set of stored templates that were determined from a set of reference bird vocalizations. The results of this relatively simple technique are favorable for both clean and noisy recordings.

Animals↗
PubMed2003

Fidelity of select restriction endonucleases in determining microbial diversity by terminal-restriction fragment length polymorphism.

An evaluation of 18 DNA restriction endonucleases for use in terminal-restriction fragment length polymorphism (T-RFLP) analysis was performed by using richness and density indices in conjunction with computer simulations for 4,603 bacterial small-subunit rRNA gene sequences. T-RFLP analysis has become a commonly used method for screening environmental samples for precursory identification and community comparison studies due to its precision and high-throughput capability. The accuracy of T-RFLP analysis for describing a community has not yet been thoroughly evaluated. In this study, we attempted to classify restriction endonucleases based upon the ability to resolve unique terminal-restriction fragments (T-RFs) or operational taxonomic units (OTUs) from a database of gene sequences. Furthermore, we assessed the predictive accuracy of T-RFLP at fixed values of community richness (n = 1, 5, 10, 50, and 100). Classification of restriction endonuclease fidelity was performed by measuring richness and density for the entire database of T-RFs. Further analysis of T-RFLP accuracy for determining richness was performed by iterative, random sampling from the derived database of T-RFs. It became apparent that two constraints were influential for measuring the fidelity of a given restriction endonuclease: (i) the ability to resolve unique sequence variants and (ii) the number of unique T-RFs that fell within a measurable size range. The latter constraint was found to be more significant for estimating restriction endonuclease fidelity. Of the 18 restriction endonucleases examined, BstUI, DdeI, Sau96I, and MspI had the highest frequency of resolving single populations in model communities. All restriction endonucleases used in this study detected < or =70% of the OTUs at richness values greater than 50 OTUs per modeled community. Based on the results of our in silico experiments, the most efficacious uses of T-RFLP for microbial diversity studies are those that address situations where there is low to intermediate species richness (e.g., colonization, early successional stages, biofilm formation).

Bacteria↗
PubMed1992

Classification of 1,198 cases of bovine lymphoma using the National Cancer Institute Working Formulation for human non-Hodgkin's lymphomas.

A retrospective histologic study was made of 1,198 cases of bovine lymphoma using the National Cancer Institute Working Formulation for human non-Hodgkin's lymphoma. This classification scheme was found to be readily applicable to bovine lymphoma. Most of the cell types described in the National Cancer Institute Working Formulation occurred in this series of bovine lymphomas, but the distribution of cell types varied markedly compared to that of human beings. Eighty-nine percent (1,067/1,198) of bovine lymphomas were high-grade tumors. The diffuse large cell type and its cleaved variant comprised 65.9% of all bovine lymphomas. Similar to the dog, but in marked contrast to human beings where at least 34% of non-Hodgkin's lymphomas were follicular, follicular tumors were found to be extremely rare in cattle (0.3% or 4/1,198). The prevalence of cell types varied significantly between the enzootic and sporadic lymphomas. The cleaved variant of the diffuse large cell type constituted 38% (406/1,072) of enzootic lymphomas versus 14% (18/126) of sporadic lymphomas. The mitotic index (100 x oil immersion field, 175 microns in diameter) of enzootic lymphomas (3.72 +/- 0.06, mean +/- standard error) was significantly greater than the mitotic index of sporadic lymphomas (2.82 +/- 0.17). We concluded that the cleaved variant of the diffuse large cell type with high mitotic index is characteristic of enzootic lymphoma. This characteristic high-grade cell type may be a consequence of the viral etiology of the enzootic form of bovine lymphoma.

Age Factors↗
PubMedDate not supplied

[Endothoracic goitre: anatomoclinical and therapeutic considerations].

Substernal goitre is a clinical condition in which the masin bulk of the enlarged gland is firmly located in the chest. The incidence of this pathology ranges in literature from 1.7% and 30%. This study examines 230 cases of substernal goitre out of a total 5.362 operations performed from 1965 to 2000, for thyroid gland pathologies (4.36%). According to their experience the Authors propose a classification based on the anatomical location of the goitre: right, left, anterior and posterior goitre are therefore identified. The surgical procedures performed include 136 subtotal thyroidectomies (59.1%), 59 emithyroidectomies (25.7%) and 23 total thyroidectomies (10%). In 12 cases the operation was confined to removal of the mediastinal mass (5.2%). The cervical approach was the only surgical access route used in all the patients, regardless of the different anatomical variants. Appreciable venous stasis, due to the mediastinal mechanical obstruction exerted by the goitre, was always evident at the operation. In order to limit the risk of bleeding during operation, careful hemostasis of the major vascular pedicles must be performed. Any attempt to legate the smallest vessel, should be avoided since it is a difficult, useless and time-consuming procedure. Minor bleeds promptly stop as soon as the pathological mass is removed. Ligation of the vascular pedicles can be easily achieved; in this way, the goitre is freed from its anatomical connections and the surgeon can safely manage the substernal portion of the mass. The mortality reported in this study was 0.43% (one patient died 30 days postoperatively due to respiratory complications), whereas the morbidity rate was 2.6%.

Adult↗
PubMed1990

[The prospective directions of research in teratology].

Unsolved problems of modern teratology are discussed. The monitoring of the congenital malformation incidence is one of the variants of evaluation and control of the mutation pressing in the population. The investigation of human foetuses obtained in artificial abortions may be very helpful in this respect. The investigation of the phenotypical manifestations of malformations in the human prenatal ontogenesis and the use of the results for the creation of notion on the malformation morphogenesis seems to be perspective. The definition of the tissue dysplasias and their classification (dystopia, dyssynchronia, hamartomas) are given. The issue of the tissue malformations during the postnatal development is not similar. They may be asymptomatic, or to disturb the function of the organ concerned, or to predispose to chronic inflammation or neoplastic growth.

Congenital Abnormalities↗
PubMed1979

[Mediastinoscopy and thoracotomy in bronchogenic carcinoma (V) (author's transl)].

The opinion of the Bronchogenic Carcinoma Cooperative Group is that mediastinoscopy is at present an irreplaceable method for the determination of the resection limits in patients with bronchogenic carcinoma. Mediastinoscopy cannot be replaced by roentgenologic or isotopic studies of the mediastinum, since the invasion of the ganglionar capsule or of the mediastinal fat can only be determined by histopathologic examination. Following a classification based on macro- and microscopic morphological criteria, surgery has achieved a 64 percent of thoracotomies with "presumably curative" resections. Patients with epidermoid carcinomas were the main candidates to surgery. Lastly the role of the so-called bronchogenic carcinoma "markers" or substances that can indirectly indicate the course of the disease is discussed. The value of humoral and cell-mediated immunologic studies for introducing other therapeutic variants after curative surgery is pointed out. The definite conclusions regarding the clinical and surgical therapeutic aspects of the Bronchogenic Carcinoma Cooperative Group are detailed.

Adenocarcinoma↗
PubMedDate not supplied

[Coagulopathic hemorrhages in the surgical treatment of cancer patients].

The hemostasis system was examined before surgery, during the principle stages of the intervention, and in the immediate postoperative period in 280 patients with various malignant tumors. The volume of blood loss during the operation varied from 280 to 14,000 ml. The studies demonstrated that blood loss due to traumatic surgical interventions is the principal factor causing the most profound disorders in the hemostasis system leading to the development of grave coagulopathic hemorrhages in cancer patients. Coagulopathic bleedings most frequently develop at a blood loss of more than 3,000 ml and course as variants and stages of the disseminated intravascular coagulation (DIC) syndrome or hemodilution coagulopathy. A massive blood loss was found to be detrimental primarily for the platelet component of the hemostasis system; besides thrombocytopenia, the aggregability of these cells reduced, this being conducive to development of hemorrhages from the small vessels. Laboratory signs of acute DIC syndrome diagnosed during surgery were shown to anticipate its clinical manifestation. A working classification of surgical hemorrhages and rapid methods for their diagnosis have been developed.

Adult↗
PubMedDate not supplied

[Correspondences from 10th to 9th Revision of the International Classification of Diseases in the causes of death lists of the National Institute of Statistics and the Regional Health Authority of Murcia in Spain].

BACKGROUND: Different countries have conducted comparability studies between Revisions 10 and 9 of the International Classification of Diseases for aggregate lists of causes of death. In Spain, the COMPARA project was aimed at evaluating the impact of the revision change. METHODS: Descriptive cross-sectional epidemiological study of 88,048 deaths recorded in Spain in 1999 with the underlying cause of death doubled coded in ICD-9 and ICD-10. The theoretical correspondences between the ICD on the lists of the National Institute of Statistics and Murcia are established. The comparability rates and their confidence intervals, and the total kappa index were calculated. RESULTS: A decline in infectious diseases (-1.7%) and viral hepatitis, (-12.3%) declined under Tenth revision, while AIDS showed an increase (5.7%). Neoplasms increased a little (0.3%) with the inclusion of the Mielodisplasic Syndrome (55.2%). Diabetes mellitus is increased (2.1%). Mental disorders declined on dementia being shifted to Alzheimer's disease (28.6%). Cardiovascular diseases dropped slightly (-1.4%), without any impact on cerebrovascular diseases, although acute myocardial infarct decreased (-0.6%) while ischemic heart disease increased (0.3%). Pneumonia decreased (-12.5%) and hepatic cirrhosis grows (4.3%). Ill-defined conditions increased due to cardiorespiratory insufficiencies. The external causes show no change without including the accuracy of ICD-9. The National Institute of Statistics 102 groups list obtained a total kappa index of 95.4%, similar to the Murcia variants. CONCLUSIONS: Although ICD-10 has a lesser overall impact, the significant comparability rates of the causes of death groups between the revisions with important absolute differences should be taken into account.

Cause of Death↗
PubMedDate not supplied

[Disorders of the membrane skeleton of erythrocytes in hereditary spherocytosis and elliptocytosis: significance of the molecular defect for pathogenesis and clinical severity].

During recent years an increasing number of inherited variants of erythrocyte membrane proteins and defects of the membrane skeleton could be described. Mostly these defects explain the pathogenesis of hemolytic anemias due to erythrocyte membrane defects. For hereditary spherocytosis and elliptocytosis a close correlation between the clinical severity and the biochemical defect was found; thus biochemical characterization can give valuable information about the expected course of the disease and the need for splenectomy. The erythrocyte membrane skeleton stretches along the inner surface of the membrane; it provides the stability of the erythrocyte under circulatory shear stress. The membrane skeleton consists of spectrin, actin, band 4.1 and band 4.9. Spectrin is the major component. In the membrane mostly all spectrin self-associates to the tetrameric form: one tetramer is formed by two alpha and two beta-chains. By denaturing SDS polyacrylamide gelelectrophoresis the composition of the membrane proteins can be analysed. The portion of tetrameric and dimeric spectrin is determined on native agarose gel electrophoresis. The concentration of spectrin in the membrane can be measured by an enzyme linked immunosorbent assay using monoclonal antibodies against human spectrin. By polymerase chain reaction and DNA sequencing the moleculargenetic cause of singular membrane defects was clarified. Hereditary spherocytosis was mostly due to a more or less diminished concentration of spectrin. Based on hematological, clinical' and biochemical observations, a new classification of spherocytosis (mild, moderate and severe form) is proposed. In addition to routine hematologic determinations and osmotic fragility, erythrocyte spectrin content is taken into account. The disease severity correlates with the diminution of spectrin. In hereditary elliptocytosis the concentration of tetrameric spectrin is reduced in about 30% of the patients. Defects of the N-terminal alpha I 80,000 dalton peptide are predominantly found. The defective alpha chain can be further studied by analysis of "tryptic" peptides after limited tryptic digestion of the spectrin. According to the reduced molecular weight of the anomalous tryptic alpha I peptide the variant spectrin alpha chains are designed as Spectrin alpha I/46, Sp alpha I/50, Sp alpha I/65, Sp alpha I/74 and Sp alpha I/78. In most cases a single amino acid substitution of the alpha chain could be proven. Until now only singular patients with hereditary elliptocytosis due to a shortened spectrin beta chain have been described. The shortening of the beta chain is due to a loss of the C-terminal phosphorylated peptide. The molecular cause is a defect at the 3' end of the beta spectrin gen, resulting in a premature termination of the peptide chain-synthesis.(ABSTRACT TRUNCATED AT 400 WORDS)

Actins↗
PubMed2005

Learning viewpoint invariant object representations using a temporal coherence principle.

Invariant object recognition is arguably one of the major challenges for contemporary machine vision systems. In contrast, the mammalian visual system performs this task virtually effortlessly. How can we exploit our knowledge on the biological system to improve artificial systems? Our understanding of the mammalian early visual system has been augmented by the discovery that general coding principles could explain many aspects of neuronal response properties. How can such schemes be transferred to system level performance? In the present study we train cells on a particular variant of the general principle of temporal coherence, the "stability" objective. These cells are trained on unlabeled real-world images without a teaching signal. We show that after training, the cells form a representation that is largely independent of the viewpoint from which the stimulus is looked at. This finding includes generalization to previously unseen viewpoints. The achieved representation is better suited for view-point invariant object classification than the cells' input patterns. This property to facilitate view-point invariant classification is maintained even if training and classification take place in the presence of an--also unlabeled--distractor object. In summary, here we show that unsupervised learning using a general coding principle facilitates the classification of real-world objects, that are not segmented from the background and undergo complex, non-isomorphic, transformations.

Action Potentials↗
PubMed2001

Endemic (African) Kaposi's sarcoma presenting as a plantar tumour.

We present a case of the aggressive variant of African endemic Kaposi's Sarcoma (AKS) which presented as a large fungating and ulcerated plantar mass. Our patient responded extremely well to chemotherapy with no recurrence for 9 months after treatment completion. AKS is one of the most common cutaneous neoplasms in black Africans and although rare in Europe, it may be seen more frequently in the future because of the ease of international travel. The existing classification of KS into five different types (classic, African-endemic, iatrogenically immunocompromised patients, epidemic HIV-related and Mediterranean-endemic) cannot address fully the many anomalies described in the disease. The detection of a new herpes simplex-like viral DNA sequence (HHV-8) in different types of KS helps to explain some of the enigma described in this disease.

Aged↗
PubMed2006

Prevalence of glucose-6-phosphate dehydrogenase deficiency in U.S. Army personnel.

The U.S. Army recently mandated that soldiers undergo glucose-6-phosphate dehydrogenase (G6PD) testing before deployment to malarious regions. We retrospectively characterize the presence and degree of G6PD deficiency in U.S. military personnel by sex, self-reported ethnicity, and World Health Organization deficiency classification through test results obtained October 1, 2004 through January 17, 2005. Data were available for 63,302 (54,874 males and 8,428 females) subjects; 2.5% of males and 1.6% of females were deficient, with most having only moderate enzyme deficiency. African American males (12.2%) and females (4.1%), along with Asian males (4.3%), had the highest rates of G6PD deficiency. Most males were found to have class III variants while most females were class IV variants. The most severely deficient were Asian males (class II). These results suggest that universal screening for G6PD deficiency is clinically warranted, and particularly essential for those male service members who self-report ethnicity as African American, Asian, or Hispanic.

Adult↗
PubMed1985

[Morphology and histogenesis problems in cervical cancer].

Both most common and rare varieties of uterine cervix carcinoma were studied light and electron microscopically. It is shown that tumours histologically classified as squamous-cell carcinoma originate either from the squamous epithelium of the ectocervix or from the metaplastic epithelium. Characteristic ultrastructural features of these histogenetic variants of squamous-cell carcinoma are described. The authors' and literature data are presented indicating that the great histological variety of adenocarcinomas and glandular-squamous carcinomas is due to the pluripotential properties of proliferating stem cells capable of forming glandular, solid and squamous-cell structures. The source of clear-cell adenocarcinoma may be not only Gartner's duct but the mullerian epithelium as well. The classification of uterine cervix carcinomas reflecting their histogenesis is proposed.

Adenocarcinoma↗
PubMed1986

A variant of early gastric carcinoma. Histologic and histochemical studies of early signet ring cell carcinomas discovered beneath preserved surface epithelium.

Gastric carcinomas hidden beneath flat and intact mucosal surface epithelium are rarely discovered. Such a tumor in the early stage is at best diagnosed as an incidental finding, so that the diagnosis is probably always a surprise to the clinician. Six such cases of early gastric carcinoma were presented. Four were intramucosal lesions and the remaining two were invasive with submucosal extension. All the tumors are composed purely of signet-ring cells (diffuse-type by Lauren's classification). Histologic examination of the six cases revealed that certain features, which are not characteristically observed in ordinary signet-ring cell carcinomas, were commonly recognized. These included compact nests of uniform signet-ring cells sharing a common cytoplasmic wall, lack of desmoplastic stromal response, and intracytoplasmic mucin predominantly composed of neutral mucopolysaccharide. These six tumors are considered to be an incipient stage of signet-ring cell carcinoma. The findings also suggest a close histogenetic relationship between these tumors and the mucous neck cells in the basal region of gastric glands. The grossly unremarkable mucosal surface and histologically innocuous appearance associated with this form of tumor are emphasized for diagnosis.

Adenocarcinoma, Mucinous↗
PubMed2004

The spectrum of mesenchymal skin neoplasms reflected by the new WHO classification.

Mesenchymal tumors are a heterogeneous group of tumors often arising in the skin and soft tissue. The tumors have been reclassified by the WHO in 2002. Benign mesenchymal tumors are about a hundred times more frequent than malignant mesenchymal tumors. Clinically, mesenchymal tumors often present as skin-colored nodes. Overall, elderly persons are more affected than younger individuals. The etiology is often unknown, sometimes there is an association with insults such as radiation, scars, or lymphedematous or venous stasis. Whereas some years ago a wide excision with a margin of 3-5 cm was performed for malignant variants, today micrographic surgery is preferred, as it can avoid mutilating procedures. Early detection and removal is critical since mesenchymal skin tumors often cannot be cured by radiation or chemotherapy.

Humans↗
PubMed1989

[Growth disorders. Recommendations for a practice-oriented classification].

Besides acute illnesses, including allergies, growth disturbances are among the most frequent reasons for parents to consult a physician about their children. The basis of diagnosis is a detailed family and personal history. Actual measurement of the parents is necessary for calculation of the patient's target height. The growth data obtained must be charted on percentile curves. Only in the second line of the diagnostic approach should the physician resort to hormone determinations and X-rays of the left hand and wrist for bone age determination. For practical purposes, growth aberrations may be subdivided into normal variants and pathologic processes. The latter may cause proportionate or disproportionate disturbances. For therapeutic reasons it is also important to know whether the deviation of growth started pre- or postnatally. Many growth disorders that develop postnatally are amenable to therapy. They include the following endocrinopathies associated with short stature: isolated growth hormone deficiency (treatment with hGH), congenital adrenal hyperplasia due to enzyme deficiencies (treatment by replacement of cortisol), idiopathic, iso-sexual precocious puberty (treatment with LHRH agonists), and hypothyroidism (treatment with thyroxine). Patients with Turner syndrome benefit from sex hormones only insofar as secondary sexual characteristics develop: these agents do not promote overall growth. The treatment of patients with tall stature by administration of estrogens/gestagens in high dosages is viewed with increasing scepticism. On the average, only a 4-cm reduction in length can be achieved if patients are treated from the onset of puberty through a bone age of 16 years. All secondary growth disturbances are improved by efficient treatment of the primary, underlying disease entity.

Body Height↗
PubMed1980

[Classification of follicular cysts: epidermal cysts including Günther sebocystomatosis, steatocystoma multiplex and trichilemmal cysts].

The clinical and histopathological nomenclature of various follicle-derived cysts is confusing. A uniform terminology, based on histopathological criteria is proposed. Cysts may develop from vellus follicles, sebaceous follicles, and terminal hair follicles. The various sections from each follicle may give rise to various types of cysts: 1. the infundibulum to epidermal cysts (e.g. epidermal cysts, comedones, milia, and scrotal cysts); 2. the sebaceous ducts and sebaceous acini to steatocystoma multiplex; 3. the infraglandular portion of the infrainfundibulum to trichilemmal cysts (atheromas). A clinical variant of epidermal cysts, the scrotal cysts, at times incorrectly called sebocystomatosis Günther, is described in 10 patients. For all types of cysts clinical and histopathological guidelines are offered.

Cysts↗
PubMed1995

[Clinical aspects and classification of unstable angina].

Unstable angina pectoris is a clinical syndrome with multiple underlying pathophysiologic mechanisms. This presentation is concerned with primary angina pectoris exclusively. In the majority of cases a rupture of an atherosclerotic plaque and an intracoronary thrombus are responsible for instable angina. The practitioner's role is to identify those patients who will develop complications with the aid of clinical parameters. Prinzmetal's angina is also instable, occurs at rest and leads to ST-segment elevation. It is most likely due to coronary spasm, developing in disease-free and atherosclerotic coronary segments alike. This variant of unstable angina is treated most successfully with calcium antagonists. The recognition of the responsible pathophysiologic mechanism permits adjustment of treatment of every patient taking into consideration the seriousness of his prognosis.

Angina Pectoris, Variant↗