Application of an immunosensor for the detection of the β-lactam antibiotic, cephalexin

Public concern surrounding antibiotic contamination in food and food products has made it imperative to develop analytical methods for their detection. Polyclonal antibodies were used in the development of a surface plasmon resonance (SPR)-based inhibition immunoassay for cephalexin. A conjugate consisting of cephalexin-bovine serum albumin (BSA) was immobilized on the dextran gel surface of the sensor chip. Binding/regeneration studies of antibody to immobilized cephalexin were studied and dissociation of the antibody from the immobilized cephalexin was easily achieved with 10 mmol l^-1 NaOH. Forty surface regeneration cycles were carried out and found to be reproducible with only a 7.4% decrease in binding over this number of regenerations. Model inhibition immunoassays for cephalexin were developed in PBS and spiked milk samples with detection ranges of 4.88 to 2,500 ng ml^-1 and 244 to 3,906 pg ml^-1, respectively.     

Fine-needle cytology of an eccrine spiradenoma of the breast: diagnosis made by a holistic approach.

Eccrine spiradenoma is a rather rare adnexal tumor of the skin. When the clinical presentation is that of a breast neoplasm, diagnosis can be difficult. As cytology was a new procedure for this tumor, the approach of choice appeared to be a holistic one. The cytologic picture showed bland groups of uniformly sized cuboid cells with scant cytoplasm, round to ovoid nuclei, and inconspicuous nucleoli, while in the groups rosettelike structures could be discerned. Only by integrating the data of clinical history, inspection, palpation, reaction on breast puncture, and immunologic findings could the diagnosis be made.     

Epidermolysis bullosa herpetiformis (Dowling-Meara type) exhibits ultrastructural derangement of tonofilaments and desmosomes

Ultrastructural and immunohistochemical studies of clinically intact skin obtained from three severe neonatal cases of epidermolysis bullosa herpetiformis (Dowling-Meara type) demonstrated disorders in the assembly of keratin intermediate filaments and desmosomes of the keratinocytes. During mitosis, K5- and K14-positive and K1- and K10-negative tonofilaments were disrupted and formed spherical bodies associated with intracytoplasmic desmosomes by invagination of the desmosomes and the adjacent plasma membrane. During the invagination process, destructive changes in the internalized membrane were noted. These were accompanied by gradual loss of reactivity with a monoclonal antibody ZK31, which detected plasma membrane adjacent to the attachment plaques of desmosomes. However, the reactivity of the attachment plaques of the internalized desmosomes for desmoplakins and desmoglein did not decline during the process of internalization. In the suprabasal layers of the epidermis, filamentous substructures and K1 and K10 appeared at the periphery of the spherical bodies. Simultaneously, the desmosomes that were sparsely located in the lower epidermis, increased in number as cell differentiation progressed. Thus, the keratinocytes attained an almost normal appearance with respect to tonofilaments and desmosomes by the time they reached the upper layer of the epidermis. These findings may be relevant to the mechanism responsible for the clinical appearance of the herpetiform blisters in epidermolysis bullosa herpetiformis, which are also characterized by spontaneous involution during childhood or when exposed to high ambient temperatures.Part of this work was presented at the annual meeting of the Japanese Society for Ultrastructural Cutaneous Biology, 12 May 1990, Tokushima, Japan, at the joint meeting of the Society for Cutaneous Ultrastructure Research and the Japanese Society for Ultrastructural Cutaneous Biology, 23–25 May 1991, Vienna, Austria, and at the sixth Conference on Disorders of Keratinization, 6 July 1991, Tokyo, Japan     

A method combining morphological, immunocytochemical and chromosomal examinations of the same cell in the study of lymphoproliferative diseases

6 cases of different lymphoproliferative diseases were studied with the new MAC (Morphology-Antibody-Chromosome) method in order to find out 1) if the abnormal karyotype is confined to the monoclonal cell population, 2) if there are, within this clone, also cells with a normal karyotype, and 3) if the method can help the pathologist to diagnose malignant lymphoproliferative diseases. The MAC method allows a simultaneous study in the same metaphase cell of the karyotype, surface markers, and some morphological features. In all cases in which a monoclonal cell proliferation was detected immunohistologically, the MAC examination showed a chromosomal abnormality for the same light chain as was detected in immunohistology, but not in other cells. In all but a single case, all mitotic cells belonging to the clonal cell proliferation had an abnormal karyotype. In this case with lambda clonality, 2/8 lambda-positive mitoses had a normal karyotype. However, all the normal mitoses occurred in small lymphocytes whereas the abnormal mitoses were seen in large blastic cells. In 1 case, the MAC method helped in confirming the diagnosis of malignant lymphoma (nodular small cleaved cell type). Especially in lymphomas composed of a mixed cell population, the MAC method makes it possible to find out which cell types have an abnormal karyotype and which have a normal karyotype.     

A review of the effects of external pressure on skin blood flow

The human foot is a complex mechanical structure consisting of bones, ligaments and joints. They act together to provide a robust system capable of absorbing and dissipating the intermitted pressure that is subjected to its plantar surface during walking to prevent soft tissue breakdown. Current studies suggest that plantar foot pressure may lead to soft tissue breakdown (e.g. neuropathic ulceration) and hence research has so far concentrated on investigating the mechanical effects of plantar foot pressure on the foot’s integrity. This has been possible through the widely available pressure and force platforms as well as in-shoe pressure systems. However, to understand how plantar foot pressure causes soft tissue breakdown it is vital to investigate both the physiological–mechanical interactions between the skin and plantar foot pressure. This review suggests that with the current advances in technology, the physiological response of skin blood flow to mechanical plantar foot pressure should be investigated and correlated further, both during static and dynamic loading, by developing a new system capable of either measuring both variables simultaneously or by synchronising two systems in real time.     

不同形状界面对界面射流的影响──彩色多普勒与激光荧光染料方法的研究

本文通过应用彩色多普勒及激光荧光染料显示射流方法研究了不同形状界面对射流的影响。结果表明对照组及平坦界面射流时，彩色多普勒与激光荧光染料两种方法无显著差异；在弯曲界面条件下，彩色多普勒射流小于激光荧光染料射流（Ｐ＜０．０１～０．０００１）。彩色多普勒研究表明不同形状界面射流大小分别与每搏容量相关好（ｒ＝０．８３～０．９９），但射流大小明显不同。凹形界面射流面积最小，平坦及凸形界面射流面积也小于对照组。研究提示不同形状界面可以导致界面射流不同程度地减小，并且彩色多普勒也不易对弯曲界面的射流完全成像。在临床上应用彩色多普勒对返流定量时，需考虑上述影响。     

Surgical treatment of acne scarring by using skin grating knife

Summary A method of dermaplaning for acne scarring using a skin graft knife is described. This surgical technique cannot be considered as a form of dermabrasion. Its advantages are reported.