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PubMed1999

Sensory nerve endings in the hard palate and papilla incisiva of the rhesus monkey.

The sensory innervation of the hard palate of the rhesus monkey was studied by light and electron microscopy. The mucosa of the hard palate is subject to a particularly heavy mechanical load requiring functional specialisation of the horny epithelium in the form of thickenings - the papilla incisiva and eight pairs of rugae palatinae. A thin layer of firm connective tissue (lamina propria) attaches the mucosa to the periost of the hard palate. Sensory nerve fibres were found most abundantly in the papilla incisiva and first rugae palatinae. Their number decreases in an aboral direction. Five types of sensory nerve endings were found. Free nerve endings were ubiquitous in the epithelium and lamina propria. Merkel nerve endings were found in the basal layer of the epithelium of the papilla incisiva and rugae palatinae. Meissner corpuscles were located in the connective tissue between epithelial pegs, while lamellated corpuscles were seen below the epithelial pegs. Ruffini corpuscles were found in the deeper layer of the lamina propria. Thus, a variety of sensory nerve endings were found in the hard palate, especially in those areas that are in close contact with the tongue during chewing of food. This rich innervation suggests an important role in monitoring the mechanical properties of food and the position of the tongue.

Animals↗
PubMed2000

Structure and mutation analysis of the gene encoding DNA fragmentation factor 40 (caspase-activated nuclease), a candidate neuroblastoma tumour suppressor gene.

We have characterised the DFFB gene, encoding the active subunit of the apoptotic nuclease DNA fragmentation factor (DFF40). DFFB maps to 1p36, near the imprinted putative tumour suppressor gene TP73. The DFFA gene (encoding the inhibitory DFF45 subunit) also maps to 1p36.2-36.3, and we show by FISH that DFFB lies distal to DFFA. We have also mapped a processed DFFB pseudogene to chromosome 9. DFFB itself has seven coding exons spanning 10 kb. Exhaustive mutation screening of 41 neuroblastomas and other tumours in which a 1p36 tumour suppressor gene is implicated showed no tumour-specific mutations. A coding region polymorphism was used to demonstrate uniformly biallelic expression in human fetal DFFB transcripts. Since the putative neuroblastoma tumour suppressor gene in distal 1p36 is predicted to be maternally expressed, the lack of imprinting and absence of somatic mutations in DFFB indicate that it is probably not the neuroblastoma tumour suppressor gene.

Apoptosis↗
PubMed2003

Innervation of the maxillary vibrissae in mice as revealed by anterograde and retrograde tract tracing.

Vibrissae are a unique sensory system of mammals that is characterized by a rich and diverse innervation involved in numerous sensory tasks with the potential for species-specific differences. In the present study, indocarbocyanine dyes (DiI and PTIR271) and confocal microscopy were combined to study the innervation of the mystacial vibrissae and vibrissa-specific sensory neuron distribution in the maxillary portion of the trigeminal ganglion of the mouse. The deeper regions of the vibrissa cavernous sinus (CS) contained a dense plexus of free nerve endings, possibly of autonomic fibers. The superficial part of this sinus displayed a massive array of corpuscular endings. Innervation in the region of the ring sinus consisted of Merkel endings and different morphological variances of lanceolate endings. The region of the inner conical body had a circular plexus of free nerve endings. In addition to confirming previous observations obtained by a variety of other techniques and ultrastructural studies, our studies revealed denser terminal receptor endings in a different distribution pattern than previously demonstrated in studies using the rat. We also revealed the distribution of sensory neurons in the trigeminal ganglion using retrograde tracing with fluorescent tracers from two nearby vibrissae. We determined that the populations of sensory neurons innervating the two vibrissae were largely overlapping. This suggests that the somatotopic maps of vibrissal projections reported at the different levels in the neuraxis are not faithfully reproduced at the level of the ganglion.

Animals↗
PubMed1995

Upper eyelid reconstruction with mucosa-lined bipedicled myocutaneous flaps.

We present a method for morphodynamic reconstruction of the upper eyelid for large full thickness defects. The main features of this single-stage operation are: reconstruction of the conjunctiva by free mucosal graft from the oral cavity; mobilisation of a bipedicled myocutaneous flap from the preseptal (or orbital) portion of the lid, anchoring of the levator to this flap and transposition of a temporofrontal flap to reconstruct the donor site of the bipedicled flap. This method is simpler and above all less invasive than other techniques used at present and at the same time allows for a good functional and aesthetic reconstruction.

Aged↗
PubMed1986

Labeling of cutaneous sensory nerve endings with axonally transported horseradish peroxidase and wheat germ agglutinin-horseradish peroxidase conjugate: a methodological study in the rat.

Practical aspects on the use of horseradish peroxidase (HRP) and wheat germ agglutinin-horseradish peroxidase conjugate (WGA-HRP) to trace peripheral cutaneous nerve endings have been studied. The parameters studied included application site of the tracer, post-application survival time, tracer concentration and tracer volume. These parameters were examined in the glabrous skin of the rat hindpaw. The best results were obtained with injections of 1 microliter WGA-HRP (20 micrograms/microliter) in dorsal root ganglia innervating the examined cutaneous region and a postinjection survival time of 18-36 h. With this approach extensive and heavy labeling was achieved of epidermal nerve endings, nerve endings in Merkel cell-neurite complexes and Meissner corpuscles. Useful, but less extensive labeling of these types of peripheral nerve endings, was obtained with injections of HRP in the lumbar spinal cord dorsal horn.

Animals↗
PubMedDate not supplied

Haemophilus influenzae sepsis resulting from pneumonia.

Haemophilus influenzae is a pleomorphic gram-negative bacterium that causes a myriad of infections in both adults and children. The organism frequently causes respiratory infections in patients with obstructive lung disease but may on occasion cause invasive infections including pneumonia with bacteremia. We report the case of a patient with underlying lung disease and metastatic malignancy in whom sepsis related to pneumonia caused by H. influenzae developed.

Aged↗
PubMed1996

The free revascularized rectus abdominis myocutaneous flap for the repair of tumour related defects in the head and neck area.

The present work reviews a series of 11 consecutive patients who have received free revascularized rectus abdominis myocutaneous flaps for primary reconstruction of soft tissues after ablative tumour surgery in the head and neck area. In 10 patients, a total or subtotal glossectomy had been performed and the flap was used to replace the resected tongue volume. In 5 of these cases, extensive perforating defects had resulted after additional resection of large portions of the chin and the cheek. Mandibular continuity was restored by a metal plate and the flap was divided into an intraoral and extraoral portion in these patients. In one patient, the flap had been used for closure of a full thickness defect of the calvarium. 9 of the 11 flaps healed uneventfully. In one case, a partial flap loss was encountered after thrombosis of the venous pedicle due to compression as a result of an unfavourable defect anatomy and flap positioning. Primary closure of the abdominal wall was achieved in all cases. A subcutaneous hematoma occurred at the donor site in one patient. According to our present experience, the rectus abdominis free flap may serve as an alternative to the frequently employed latissimus dorsi flap in maxillofacial reconstructions while it offers the possibility for flap elevation simultaneously to the surgical procedures in the head and neck area.

Arteries↗
PubMed2000

Recognition and management of unusual cutaneous tumors.

This article has briefly outlined some of the more unusual cutaneous neoplasms that may be encountered in a dermatologic practice. Although rare, they must always be kept in mind and included in the differential diagnosis. Because of the highly aggressive nature of many of these tumors, delay in diagnosis and treatment could be fatal. A high level of suspicion is necessary for the correct prebiopsy diagnosis.

Carcinoma, Merkel Cell↗
PubMed1999

Coping with cancer. A personal odyssey.

Building on personal experience, the psychological impact of cancer is reviewed. The subspecialty of psycho-oncology is a recent development within oncology, reflecting the increased interest in behavioral, psychological, and social factors in cancer prevention, treatment, and in improving the quality of life of patients with cancer at all stages through counseling and educational programs. Early identification of patients who are coping poorly is important for compliance with treatment and control of distress. It is equally important to recognize and diagnose common psychological disorders, primarily anxiety and depressive symptoms, which can occur. Referral for counseling to a mental health professional familiar with the care of patients with cancer may be indicated. My successful confrontation with cancer led to emotional growth. For those who cannot be sanguine about their experience, there may still be ways to reduce its, at times, devastating psychological impact. Hopefully, the days in which cancer patients had to suffer alone, in secrecy, and in fearful silence, are disappearing.

Adaptation, Psychological↗
PubMed2001

The roles and functions of cutaneous mechanoreceptors.

Combined psychophysical and neurophysiological research has resulted in a relatively complete picture of the neural mechanisms of tactile perception. The results support the idea that each of the four mechanoreceptive afferent systems innervating the hand serves a distinctly different perceptual function, and that tactile perception can be understood as the sum of these functions. Furthermore, the receptors in each of those systems seem to be specialized for their assigned perceptual function.

Animals↗
PubMed2003

Neuroendocrine differentiated carcinomas of the breast: a distinct entity.

UNLABELLED: Some primary carcinomas of the breast have been classified as neuroendocrine. In this paper we report on 12 cases of neuroendocrine carcinoma of the breast displaying common and uncommon histological features. MATERIALS AND METHODS: All patients were aged from 43 to 79 (median 66.5) years. The tumors were unilateral and ranged from 0.8 to 7 cm (median 2.35 cm) in diameter. Four tumors were classified as solid cohesive, two as solid papillary, one as Merkel cell-like, two as cellular mucinous, two as cellular mucinous with micropapillary features and one as cellular mucinous with prominent signet ring cells. The tissues were fixed in formalin and routinely processed. All materials were stained with PAS, Alcian blue and also hematoxylin and eosin. Immunohistochemical examination was carried out by the avidin-biotin method using the following antibodies: estrogen receptor protein, progesterone receptor protein, p53, cerbB-2, Ki67, neuron-specific enolase, chromogranin, and synaptophysin. RESULTS: In all cases the tumor cells were stained positively with NSE. Synaptophysin and chromogranin positivity was detected in 11 and five cases, respectively. The prominent histological features were: extensive intraductal growth, pseudorosettes and palisades, low-grade cytologic atypia, plasmacytoid appearance of the tumor cells, and intracellular and extracellular mucin. CONCLUSION: Neuroendocrine-differentiated carcinoma of the breast is a rare and distinct category with different histological subtypes.

Adult↗