Light and Electron Microscopic Study of an Invasive Cribriform Carcinoma with Extensive Microcalcification Developing in a Breast with Silicone Augmentation

Although recent epidemiologic studies suggest that silicone augmentation of the breast is not associated with an increased risk of mammary carcinoma, cases of breast carcinoma arising in augmented breasts are being increasingly encountered as a large number of patients who had augmentation are getting older. A case of a 51-year-old woman with a 20-year history of breast augmentation who developed an invasive cribriform carcinoma associated with extensive microcalcification is presented. The patient had submammary silicone implants 20 years ago that were replaced, because of local complications, in subpectoral positions 10 years later. Dispersive X-ray microanalysis failed to demonstrate silicone in sections of the tumor and adjacent breast tissue. Appropriately fixed tumor tissue was available for electron microscopic examination. The tumor cells were rich in mitochondria, and their luminal surfaces were endowed with abundant microvilli, but the cell surfaces that came closest to the calcified microspheriols were devoid of microvilli and had cellular buddings between the microspheriols. It is suggested that the tumor cells might have been actively involved in the process of microcalcification.     

Monitoring hemodialysis vascular access by digital phonoangiography

We are intrigued by the possibility of using digital spectral analysis to detect hemodialysis vascular access stenosis. Such a monitor could be inexpensive, noninvasive, and portable enough to allow continuous monitoring. This report suggests how individuals wishing to conduct such research can use a simple but effective transducer design we have employed, how the data so obtained can be analyzed in the time and frequency domains using inexpensive digital signal processing software available via the Internet, and how data recordings might be shared via the Internet to facilitate collaboration. © 2002 Biomedical Engineering Society. PAC2002: 8763Df, 8780Tq     

Grafts of dissociated cerebellar cells containing Purkinje cell precursors organize into zebrin I defined compartments

Summary A prominent feature of the mammalian cerebellum is its organization into parasagittal compartments. One marker of such compartments is the zebrin I molecule that is expressed by bands of Purkinje cells (PC). In order to understand better the basis for the development of this organization, we have transplanted dissociated rat cerebellar anlage, taken during the period of proliferation of PC precursors, into kainic acid lesioned adult rat cerebellum. As previously observed, the resultant grafts exhibited trilaminar structures reminiscent of the normal cerebellum. In every case, the PC in the resultant grafts were organized into zebrin I + and — compartments. In one case, most of the grafted PC were integrated into a region of PC deficient host molecular layer that was induced by pretreatment with kainic acid. Clear bands defined by zebrin I reactivity were seen where groups of the grafted PC had entered the host molecular layer. These bands did not correlate in distribution or size with host bands. Hypotheses compatible with these findings that involve specific and non-specific aggregation of PC are discussed.     

纳曲酮对移植排异反应的抑制作用

以小鼠心肌组织异位移植和混合淋巴细胞反应为整体和离体模型，观察了阿片受体阻断剂纳曲酮对移植排异反应的影响。结果显示：给动物从术前开始腹腔注射纳曲酮共１０天（每日二次，每次５ｍｇ／ｋｇ）可明显延长移植心肌组织的存活时间；加入纳曲酮（１０－４～１０－８ｍｏｌ／Ｌ）对混合淋巴细胞反应有抑制作用并呈量效关系。同时还观察到，给正常小鼠腹腔注射纳曲酮３天以上，可引起动物脾细胞由ＣｏｎＡ诱导的淋巴细胞转化反应受抑制。以上结果说明纳曲酮可抑制移植排异反应，此作用有可能是通过阻断内源性阿片肽所致。     

Synaptic mechanisms acting on lumbar motoneurons during postural augmentation induced by serotonin injection into the rostral pontine reticular formation in decerebrate cats

Intrapontine microinjections of serotonin in acutely decerebrated cats resulted in the bilateral augmentation of the postural muscle tone of the hindlimbs. Optimal injection sites were located in the dorsomedial part of the rostral pontine reticular formation corresponding to the nucleus reticularis ponds oralis (NRPo). In this study, attempts were made to elucidate the cellular basis for the serotoninergically induced augmentation of postural muscle tone by recording the electromyographic (EMG) activity of hindlimb extensor muscles, the monosynaptic reflex responses evoked by electrical stimulation of group Ia muscle afferent fibres and the membrane potentials of hindlimb alpha-motoneurons (MNs). Serotonin injections resulted not only in the augmentation of the EMG activity of gastrocnemius soleus muscles, but also in the restoration of EMG suppression, which was induced by previous injection of carbachol into the NRPo. Extensor and flexor monosynaptic reflex responses were facilitated by serotonin injections into the NRPo. Such reflex facilitation was not induced by serotonin injections into the mesencephalic or the medullary reticular formation. Intrapontine serotonin injections resulted in membrane depolarization of extensor and flexor MNs with decreases in input resistance and rheobase. Spontaneous depolarizing synaptic potentials (EPSPs) increased in both frequency and amplitude. Peak voltage of Ia monosynaptic EPSPs also increased. Serotonin injections which followed carbachol injections resulted in membrane depolarization of MNs along with an increase in the frequency of spontaneous EPSPs and a decrease in carbachol-induced inhibitory postsynaptic potentials. Following pontine carbachol injections, antidromic and orthodromic responses in MNs were suppressed. Discharges of MNs evoked by intracellular current injections were also suppressed, but were restored following serotonin injections. These results indicate that postsynaptic excitation, presynaptic facilitation and disinhibition (withdrawal of postsynaptic inhibition) simultaneously act on the hindlimb MNs during serotonin-induced postural augmentation and restoration.     

Resolution of late-developing periprosthetic breast infections without prosthesis removal

Based on prior experience with implant exposure, an aggressive regimen to eradicate periprosthetic infections has proven successful in delayed gram-positive and gram-negative bacterial infections and in atypical microbacterial infections. The objective of the salvage procedure is to retain a prosthesis, to maintain breast contour, and to avoid psychological and physical consequences of prosthesis removal. The salvage procedure involves topical antisepsis, contracture release if needed, systemic and topical antibiotics with intermittent or continuous irrigation, and reinforcement of incision lines in selected cases using local tissue flaps.     

Anastomotic false aneurysms with aortic Dacron graft after twenty-five years

One of the early diamond crimped knitted polyester (Dacron) grafts was surgically excised after implantation for 25 years in the aorto-billiac position because of false aneurysm formation at the three anastomotic sites. The sutures were no longer visible. While the areas around the false aneurysm were poorly incorporated, the graft limbs were well encapsulated with some endothelial-like cells on the luminal surface. The integrity of the graft was well preserved despite mild fraying and the disruption of one stitch.     

The bilateral conchal cartilage graft: A new technique in augmentation rhinoplasty

The most common procedures to reconstruct a severe saddle-nose deformity are autogenous costal cartilage, iliac bone grafting, or Silastic implants. Each of them has its specific disadvantages. As an alternative solution, an autogenous bilateral conchal graft in sand-wich technique is described. A 3-layer graft for the dorsum and a 2-layer graft to support the depressed columellar-tip area grants a more natural and elastic reconstruction of the nasal framework. The conchal grafts are taken by an incision made on the preauricular surface of the ear. How to plane the curved grafts by meticulous cross-hatching and to immobilize them in the recipient area by transcutaneous suturing is demonstrated.Presented at the VIII International Congress of Plastic and Reconstructive Surgery, Montreal, Canada, June, 1983     

Use of biologics in rotator cuff disorders: Current concept review

Poor tendon to bone healing following rotator cuff repair has led to the continued interest and investigation into biological augmentation. The biology of tendinopathy is not fully understood and consequently the availability of disease modifying therapeutic targets is limited. A ceiling of benefit has been reached by mechanical optimisation of rotator cuff repair and thus, in order to improve healing rates, a biological solution is required. This review focuses on the strategies to biologically augment rotator cuff disorders with an emphasis on rotator cuff repair. Leucocyte rich platelet rich plasma has been shown to improve healing rates without clinically relevant improvements in outcome scores. Similarly, improved healing rates have also been reported with bone marrow stimulation and in long-term follow-up with bone marrow concentrate. Extracellular matrix (ECM) and synthetic scaffolds can increase healing through mechanical and or biological augmentation. A potential third category of scaffold is bio-inductive and has no mechanical support. Studies involving various scaffolds have shown promising results for augmentation of large to massive tears and is likely to be most beneficial when tendon quality is poor, however level I evidence is limited.