Biogeographical boundaries and Monmonier's algorithm: a case study in the northern Neotropics

Aim  To use Monmonier's algorithm, a spatially explicit technique, to elucidate positions of biogeographical boundaries in the northern Neotropics.
Location  The northern Neotropics (Isthmus of Tehuantepec, Mexico, south to trans-Andean Colombia).
Methods  We compiled avifaunal lists for 36 forested sites from the literature, museum records, field notes, and web sources. We constructed distance matrices as inverse Jaccard's similarity, used Monmonier's algorithm to place biogeographical boundaries, and created bootstrap matrices to determine the relative strength of boundaries.
Results  Biogeographical boundaries with the best support separated lowland (< 1000 m) and montane sites and areas with a distinct historical background, such as seaways, suture zones, volcanic peaks, and former islands.
Main conclusions  Monmonier's algorithm used with distance (dissimilarity) data effectively identified biogeographical boundaries consistent with historical processes and with past research. Montane sites tended to be circumscribed by sharp boundaries, emphasizing their isolation and higher endemism. Lowland sites, by contrast, tended to be homogeneous, suggesting that dispersal has played a much larger role at low elevations. Former seaways, as in the Nicaraguan Depression and extended Bay of Urabá, yielded boundaries, but typically for highland avifauna only. In addition to providing a rigorous (bootstrap support) and heuristic (direct mapping) means of locating biotic boundaries, Monmonier's algorithm can be a valuable tool for conservation planning.     

Fine needle aspiration biopsy in the evaluation of lymphoreticular tumors of the thorax

The role of fine needle aspiration (FNA) biopsy in the evaluation of lymphoreticular disorders involving the lung and mediastinum was evaluated in a study of 16 cases from the authors' institutions. The cytologic material from these cases was reviewed, and the original cytologic interpretations were compared to the tissue diagnoses, with the overall accuracy of the cytologic interpretation evaluated. There were no false-positive diagnoses of malignancy in this series. A definite diagnosis of malignant lymphoma was most readily made in those cases in which the lymphoma was of the large-cell type. Small-cell and mixed large-cell and small-cell lymphoid proliferations were less able to be definitively interpreted, with pseudolymphoma presenting particular difficulty. The results support the conclusion that FNA biopsy can be useful in evaluating these lesions but also emphasize the fact that accurate diagnosis requires correlation of cytologic, clinical and laboratory data.     

False alarms in a slit-scan flow system: causes and occurrence rates. Implications and potential solutions.

A slit-scan technique was developed as a basis for an automated prescreening system for gynecologic cytology. A flow system based on this technique was fabricated and tested and results indicated that false alarms (misclassification of objects or events from normal specimens as abnormal) are the greatest remaining obstacle to development of an automated prescreening instrument. A dual view correlation system was fabricated to provide exact image-contour correlation in flow and permit precise determination of causes and occurrence rates of false alarms. This paper presents data from correlation analyses of 23 normal cytologic specimens. Major causes of false alarms and their implications to automated prescreening are discussed. A technique that would eliminate the majority of false alarms in flow is presented.     

Pemphigus vulgaris and microinvasive squamous-cell carcinoma of the uterine cervix

Although patients with disseminated pemphigus vulgaris may have involvement of the uterine cervix, such involvement is often detected only after vaginal discharge or bleeding. When a cervical smear is obtained, distinctive cytologic abnormalities may be observed; these may be attributed to the changes of pemphigus or to an associated reparative/inflammatory reaction. This study documents the first two cases of microinvasive squamous-cell carcinoma of the uterine cervix developing in association with uterine cervical pemphigus. The gross pathologic, cytologic and histologic features of these lesions are illustrated. The cytologic criteria that may be helpful in distinguishing between cells derived from microinvasive squamous-cell carcinoma and pemphigus of the uterine cervix are described.