Accurate Differentiation (accurate + differentiation)

Distribution by Scientific Domains

Selected Abstracts

The quality and size of yolk sac in early pregnancy loss

Fu-Nan CHO
Abstract Background:, Accurate differentiation between normal pregnancy and pregnancy loss in early gestation remains a clinical challenge. Aims:, To determine whether ultrasound findings of yolk sac size and morphology are valuable in relation to pregnancy loss at six to ten weeks gestation. Methods:, Transvaginal ultrasonography was performed in 111 normal singleton pregnancies, 25 anembryonic gestations, and 18 missed abortions. Mean diameters of gestational sac and yolk sac were measured. The relationship between yolk sacs and gestational sacs in normal pregnancies was depicted. The yolk sacs ultrasound findings in cases of pregnancy loss were recorded. Results:, In normal pregnancies with embryonic heartbeats, a deformed or an absent yolk sac was never detected. Sequential appearance of yolk sac, embryonic heartbeats and amniotic membrane was essential for normal pregnancy. The largest yolk sac in viable pregnancies was 8.1 mm. Findings in anembryonic gestations included an absent yolk sac, an irregular-shaped yolk sac and a relatively large yolk sac (> 95% upper confidence limits, in 11 cases). In cases of missed abortion with prior existing embryonic heartbeats, abnormal findings included a relatively large, a progressively regressing, a relatively small, and a deformed yolk sac (an irregular-shaped yolk sac, an echogenic spot, or a band). Conclusion:, A very large yolk sac may exist in normal pregnancy. When embryonic heartbeats exist, the poor quality and early regression of a yolk sac are more specific than the large size of a yolk sac in predicting pregnancy loss. When an embryo is undetectable, a relatively large yolk sac, even of normal shape, may be an indicator of miscarriage. [source]

Paroxysmal Motor Disorders of Sleep: The Clinical Spectrum and Differentiation from Epilepsy

EPILEPSIA, Issue 11 2006
Christopher P. Derry
Summary:, The diagnosis of paroxysmal events in sleep represents a significant challenge for the clinician, with the distinction of nocturnal epilepsy from nonepileptic sleep disorders often the primary concern. Diagnostic error or uncertainty is not uncommon in this situation, particularly with respect to nocturnal frontal lobe epilepsy (NFLE), which has a variable and often unusual presentation. Such errors can be minimized if the range of nonepileptic disorders with motor activity in sleep is fully appreciated. Here we review these disorders, before discussing the important clinical and electrographic features that allow their accurate differentiation from seizures. Particular emphasis is placed on the differentiation of nocturnal frontal lobe epilepsy from non,rapid eye movement (NREM) arousal disorders and other parasomnias. The value of recording episodes with video EEG polysomnography is discussed. [source]

Identification of campylobacteria isolated from Danish broilers by phenotypic tests and species-specific PCR assays

M. Wainų
Abstract Aims: To validate a phenotypic Campylobacter species identification method employed to identify campylobacters in broilers by comparison with campylobacterial species identification using various species-specific PCR analyses. Methods and Results: From a collection of 2733 phenotypically identified campylobacterial cultures, 108 Campylobacter jejuni cultures and 351 campylobacterial cultures other than Camp. jejuni were subjected to various species-specific PCR assays. On the basis of the genotypic tests, it was demonstrated that Camp. jejuni and Camp. coli constituted approx. 99% of all cultures, while other species identified were Helicobacter pullorum, Camp. lari and Camp. upsaliensis. However, 29% of the 309 Camp. coli cultures identified by phenotypic tests were hippurate-variable or negative Camp. jejuni cultures, whereas some Camp. lari cultures and unspeciated campylobacter cultures belonged to H. pullorum. It was also notable that 2,6% of the cultures were, in fact, mixed cultures. Conclusions: The phenotypic identification scheme employed failed to appropriately differentiate Campylobacter species and particularly to identify the closely related species, H. pullorum. Significance and Impact of the Study: Future phenotypic test schemes should be designed to allow a more accurate differentiation of Campylobacter and related species. Preferably, the phenotypic tests should be supplemented with a genotypic strategy to disclose the true campylobacterial species diversity in broilers. [source]

Olfactory Neural Cells: An Untapped Diagnostic and Therapeutic Resource

Christopher Perry MBBS, FRACS
Abstract Objective This is an overview of the cellular biology of upper nasal mucosal cells that have special characteristics that enable them to be used to diagnose and study congenital neurological diseases and to aid neural repair. Study Design After mapping the distribution of neural cells in the upper nose, the authors' investigations moved to the use of olfactory neurones to diagnose neurological diseases of development, especially schizophrenia. Olfactory-ensheathing glial cells (OEGs) from the cranial cavity promote axonal penetration of the central nervous system and aid spinal cord repair in rodents. The authors sought to isolate these cells from the more accessible upper nasal cavity in rats and in humans and prove they could likewise promote neural regeneration, making these cells suitable for human spinal repair investigations. Methods The schizophrenia-diagnosis aspect of the study entailed the biopsy of the olfactory areas of 10 schizophrenic patients and 10 control subjects. The tissue samples were sliced and grown in culture medium. The ease of cell attachment to fibronectin (artificial epithelial basement membrane), as well as the mitotic and apoptotic indices, was studied in the presence and absence of dopamine in those cell cultures. The neural repair part of the study entailed a harvesting and insertion of first rat olfactory lamina propria rich in OEGs between cut ends of the spinal cords and then later the microinjection of an OEG-rich suspension into rat spinal cords previously transected by open laminectomy. Further studies were done in which OEG insertion was performed up to 1 month after rat cord transection and also in monkeys. Results Schizophrenic patients' olfactory tissues do not easily attach to basement membrane compared with control subjects, adding evidence to the theory that cell wall anomalies are part of the schizophrenic "lesion" of neurones. Schizophrenic patient cell cultures had higher mitotic and apoptotic indices compared with control subjects. The addition of dopamine altered these indices enough to allow accurate differentiation of schizophrenics from control patients, leading to, possibly for the first time, an early objective diagnosis of schizophrenia and possible assessment of preventive strategies. OEGs from the nose were shown to be as effective as those from the olfactory bulb in promoting axonal growth across transected spinal cords even when added 1 month after injury in the rat. These otherwise paraplegic rats grew motor and proprioceptive and fine touch fibers with corresponding behavioral improvement. Conclusions The tissues of the olfactory mucosa are readily available to the otolaryngologist. Being surface cells, they must regenerate (called "neurogenesis"). Biopsy of this area and amplification of cells in culture gives the scientist a "window to the developing brain," including early diagnosis of schizophrenia. The "Holy Grail" of neurological disease is the cure of traumatic paraplegia and OEGs from the nose promote that repair. The otolaryngologist may become the necessary partner of the neurophysiologist and spinal surgeon to take the laboratory potential of paraplegic cure into the day-to-day realm of clinical reality. [source]

Periarticular bone structure in rheumatoid arthritis patients and healthy individuals assessed by high-resolution computed tomography

Christian M. Stach
Objective To define the nature of structural bone changes in patients with rheumatoid arthritis (RA) compared with those in healthy individuals by using the novel technique of high-resolution microfocal computed tomography (micro-CT). Methods Fifty-eight RA patients and 30 healthy individuals underwent a micro-CT scan of the proximal wrist and metacarpophalangeal joints. Bone lesions such as cortical breaks, osteophytes, and surface changes were quantified on 2-dimensional (2-D) slices as well as by using 3-D reconstruction images, and exact localization of lesions was recorded. Results Micro-CT scans could detect bone lesions <0.5 mm in width or depth. Small erosions could be observed in healthy individuals and RA patients, whereas lesions >1.9 mm in diameter were highly specific for RA. Cortical breaks were mostly found along the radial sites of the metacarpal heads. No significant difference in the presence of osteophytes between healthy individuals and RA patients was found. Cortical surface changes, presumably cortical thinning and fenestration, became evident from 3-D reconstructions and were more pronounced in RA patients. Conclusion Micro-CT allows exact detection of morphologic changes of juxtaarticular bone in healthy individuals and RA patients. Even healthy individuals occasionally show bone changes, but the severity of these lesions, with the exception of osteophytes, is greater in RA patients. Thus, micro-CT allows accurate differentiation among physiologic bone changes in joints and among types of pathologic bone damage resulting from RA. [source]