A new force measurement device for evaluating finger extension function in the healthy and rheumatoid arthritic hand.

Although often neglected, finger extension force is of great importance for developing grip strength. This paper describes the design and evaluation of a new finger extension force measurement device (EX-it) based on the biomechanics of the hand. Measurement accuracy and test-retest reliability were analysed. The device allows measurements on single fingers as well as all the fingers (excluding the thumb) of both healthy and deformed hands. The coefficient of variation in the device was 1.8% of the applied load, and the test-retest reliability showed a coefficient of variation no more than 7.1% for healthy subjects. This study also provides reference values for finger extension force in healthy subjects and patients with rheumatoid arthritis (RA). Significant differences were found in extension strength between healthy subject and RA patients (men, p < 0.05 and women, p < 0.001). EX-it provides objective and reliable data on the extension force capacity of normal and dysfunctional hands and can be used to evaluate the outcome of therapeutic interventions after hand trauma or disease.

The vulval vestibular mucosa-morphological effects of oral contraceptives and menstrual cycle.

BACKGROUND: An erythematous and hypersensitive vestibular mucosa has been observed during the use of combined oral contraceptives (COC). Hormonal effects on the vestibular morphology have not been studied. OBJECTIVES: Our aim was to evaluate the morphology of the vulval vestibular mucosa during the influence of COC and during the menstrual cycle. METHODS: Forty-five healthy women (20 using COC and 25 not using COC) were included. A 6-mm punch biopsy was obtained from the right posterior vestibule on days 7-11 of the menstrual cycle. A corresponding biopsy was taken 2 weeks later in 16 women without COC. The epithelial morphology was estimated by measuring interdermal papilla distance, dermal papilla to surface, from basal layer to surface and width of dermal papillae. A histopathological assessment was made. RESULTS: The vulval vestibular mucosa of women using COC displayed a larger distance between the dermal papillae (P = 0.04) and a larger space from the dermal papillae to the epithelial surface (P = 0.03) compared with controls in the follicular phase. Women without COC displayed a larger interdermal papilla distance in the luteal phase compared with the follicular phase, P = 0.02. Histopathology showed more superficial blood vessels in the COC users (P < 0.01). CONCLUSIONS: The vulval vestibular mucosa of women with COC display an altered morphological pattern with shallow and sparse dermal papillae compared with the follicular phase. Similar findings are seen in women without COC during the luteal phase which indicate a gestagenic effect on the mucosa. Associations between the morphological pattern and changes in mucosal mechanical sensitivity require further studies.

Active "itch fibers" in chronic pruritus.

An itch-specific neuronal pathway was recently discovered in healthy humans and animals. Here the authors report that activity in this specific pathway coincides with itch under pathophysiologic conditions in a patient with chronic pruritus. Microneurographic recordings from the symptomatic area revealed spontaneous activity in six single C-fiber afferents that had the characteristic features of "itch fibers." Itch may be caused by activity in a specific subpopulation of C-fiber afferents.

Effects of long-term administration of cancer-promoting substances on oral subepithelial mast cells in the rat.

The role of oral subepithelial mast cells in the defence against tumours is a matter of controversy. The effect of established and suggested carcinogens, such as the carcinogen 4-nitroquinoline-N-oxide (4-NQO) and Herpes simplex virus type 1 (HSV-1), in combination with oral snuff on lower lip subepithelial mast cells (MC) was studied in rats. The rats were exposed to prolonged use of oral snuff. The test substances were administered in a surgically created canal in the lower lip of the rats. There were 15 rats in each test group and 10 rats in the control group. The amount of countable subepithelial mast cells decreased significantly when the rat oral mucosa was exposed to the oral carcinogen 4-NQO but the effect of oral snuff and HSV-1 infection was weak. Our findings suggest that mast cells play a role in immunological cell defence against chemical carcinogens. Further studies are needed to clarify the mechanisms.

The expression of cyclooxygenase 2 and inducible nitric oxide synthase indicates no active inflammation in vulvar vestibulitis.

BACKGROUND: Although women with vulvar vestibulitis syndrome have principal symptoms of inflammation such as local erythema and pain in the mucosa around the vaginal introitus, it is not clear if vestibulitis is an inflammatory condition. Cyclooxygenase 2 and inducible nitric oxide synthase are known to be upregulated during inflammation. The aim of the present study was to analyze the expression of these enzymes in the vestibular mucosa in order to evaluate the inflammatory activity in the tissue. METHODS: Ten women fulfilling Friedrich's criteria of vulvar vestibulitis syndrome and ten control subjects were included in the study. Punch biopsies were obtained from the vestibular mucosa for analysis of cyclooxygenas 2 and inducible nitric oxide synthase, using indirect immunohistochemistry and Western dot-blot analyses. RESULTS: Both methods used showed low expression of cyclooxygenas 2 and inducible nitric oxide synthase in the vestibular mucosa of all women. There was no difference observed between the groups. CONCLUSIONS: There is a low expression of the inflammatory markers cyclooxygenas 2 and inducible nitric oxide synthase in the vestibular mucosa of women with vulvar vestibulitis syndrome as well as in healthy control subjects. The results indicate no active inflammation present and imply that topical corticosteroids in the treatment of vulvar vestibulitis are unfounded.

Increased blood flow and erythema in the posterior vestibular mucosa in vulvar vestibulitis(1).

OBJECTIVE: To evaluate vascular changes as a possible underlying cause of mucosal erythema in women with vulvar vestibulitis. METHODS: Laser Doppler perfusion imaging was used to map the superficial blood flow in the vestibular mucosa in 20 women with vestibulitis and in 21 healthy control subjects. A possible correlation between perfusion values and graded erythema (1-5) around the vaginal introitus was analyzed. Changes in microvascular density in the posterior part of the mucosa were investigated in sections from ten patients and ten controls by a computer-assisted image-processing program. Induced vasoconstriction of terminal arterioles in the same posterior area was also studied. RESULTS: Significant increases in perfusion values were registered in the posterior parts of the vestibular mucosa in patients compared with controls. The highest blood flow was registered in the posterior fourchette. The most pronounced erythema was also located in the posterior vestibule in the patients. However, there was no significant correlation between perfusion values and degree of erythema in the same individual. The microvascular density or the ability of vestibular arterioles to constrict did not differ between patients and controls. CONCLUSION: Women with vestibulitis have an increased superficial blood flow and erythema in the posterior parts of the vestibular mucosa. The increased perfusion, most probably caused by a neurogenic vasodilatation contributes to, but does not fully explain the erythema. Atrophic changes of the surface epithelium should also be considered in the evaluation of an erythema.

Electrically evoked neuropeptide release and neurogenic inflammation differ between rat and human skin.

Protein extravasation and vasodilatation can be induced by neuropeptides released from nociceptive afferents (neurogenic inflammation). We measured electrically evoked neuropeptide release and concomitant protein extravasation in human and rat skin using intradermal microdialysis. Plasmapheresis capillaries were inserted intradermally at a length of 1.5 cm in the volar forearm of human subjects or abdominal skin of rats. Capillaries were perfused with Ringer solution at a flow rate of 2.5 or 1.6 microl min(-1). After a baseline period of 60 min capillaries were stimulated electrically (1 Hz, 80 mA, 0.5 ms or 4 Hz, 30 mA, 0.5 ms) for 30 min using a surface electrode directly above the capillaries and a stainless-steel wire inserted in the capillaries. Total protein concentration was assessed photometrically and calcitonin gene-related peptide (CGRP) and substance P (SP) concentrations were measured by enzyme-linked immunosorbent assay (ELISA). In rat skin, electrical stimulation increased CGRP and total protein concentration in the dialysate. SP measurements showed a larger variance but only for the 1 Hz stimulation was the increased release significant. In human skin, electrical stimulation provoked a large flare reaction and at a frequency of 4 Hz both CGRP and SP concentrations increased significantly. In spite of the large flare reactions no protein extravasation was induced, which suggests major species differences. It will be of interest to investigate whether the lack of neurogenic protein extravasation is also valid under pathophysiological conditions.

Time course of post-excitatory effects separates afferent human C fibre classes.

1. To study post-excitatory changes of conduction velocity, action potentials were recorded from 132 unmyelinated nerve fibres (C fibres) in cutaneous fascicles of the peroneal nerve using microneurography in healthy human subjects. The 'marking' technique was used to assess responsiveness to mechanical and heat stimuli or sympathetic reflex provocation. 2. C fibres were classified into three major classes: mechano-responsive afferent (n = 76), mechano-insensitive afferent (n = 48) and sympathetic efferent C fibres (n = 8). 3. During regular stimulation at 0.25 Hz, conditioning pulses were intermittently interposed. Changes of conduction velocity were assessed for different numbers of conditioning impulses and varying interstimulus intervals (ISIs). For all three fibre classes the latency shift following conditioning pulses at an ISI of 1000 ms increased linearly with their number (n = 1, 2 and 4). However, the absolute degree of conduction velocity slowing was much higher in the 32 mechano-insensitive fibres as compared with 56 mechano-responsive or 8 sympathetic fibres. 4. Single additional pulses were interposed at different ISIs from 20 to 2000 ms. For 20 mechano-responsive fibres conduction velocity slowing increased with decreasing ISI (subnormal phase). In contrast, for 16 mechano-insensitive C fibres the conduction velocity slowing decreased with shorter ISIs, and at values lower than 417 +/- 49 ms (mean +/- s.e.m.) the conduction velocity of the conditioned action potential was faster than before (conduction velocity speeding). This supernormal phase had its maximum at 69 +/- 10 ms. 5. In this study we provide, for the first time, direct evidence of relative supernormal conduction in human mechano-insensitive C fibres. The implications for temporal coding in different afferent C fibre classes are discussed.

Denervation of periurethral prostatic tissue by transurethral microwave thermotherapy.

PURPOSE: To determine whether transurethral microwave thermotherapy (TUMT) affects innervation of the urethra and periurethral prostate. MATERIAL AND METHODS: Ten patients with troublesome benign prostatic hyperplasia (BPH) were treated with TUMT 1 week prior to transurethral resection of the prostate (TURP). At surgery, a biopsy was taken for histological examination and for immunohistochemical staining of the non-specific neuromarker protein gene product (PGP) 9.5. Control material consisted of identical biopsies from 10 patients undergoing TURP because of BPH, but not subjected to TUMT prior to surgery. RESULTS: Histological examination revealed well-preserved, non-necrotic tissues in all biopsies. Nerve fibres were completely or almost absent in the smooth muscle layer in all but one of the TUMT cases, whereas all non-TUMT patients exhibited large numbers of nerve fibres in the smooth muscle layer. CONCLUSIONS: TUMT does affect innervation of the urethra and periurethral prostatic tissue.

Neurochemical characterization of the vestibular nerves in women with vulvar vestibulitis syndrome.

Women with vulvar vestibulitis syndrome (VVS) have a distinct burning pain provoked by almost any stimuli in the area around the vaginal introitus. In a previous study we observed an increased number of intraepithelial free nerve endings in women with VVS. The aim of the present study was to neurochemically characterize the superficial nerves in the vulvar vestibular mucosa of women with VVS. Immunohistochemical methods were used to detect neuropeptides normally found in various types of nerve fibers. Calcitonin gene-related peptide, which is known to exist in nociceptive afferent nerves, was the only neuropeptide detected in the superficial nerves of the vestibular mucosa. These findings confirm our previous theory that the free nerve endings within the epithelium are nociceptors.

Intraepidermal nerves in human skin: PGP 9.5 immunohistochemistry with special reference to the nerve density in skin from different body regions.

The intraepidermal nerves of normal adult human skin were demonstrated by employing a powerful marker of neuronal elements, protein gene product (PGP) 9.5. There were two types of epidermal nerves, free nerve endings and nerves in the Merkel cell-neurite complex. The free nerve endings distributed to, and terminated in, all the strata basale, spinosum and granulosum, and they appeared as thin fibers, mostly varicose, branched or single processed, straight or bent. They existed at every site of the human body, including face, trunk and extremities. However, the densities of these nerves varied in different body parts and areas. The number of nerves decreased from the trunk to the distal parts of the limbs, and small denser 'innervation patches' showed up in the epidermis which were identified in confocal microscopy as one morphologic terminal field coming from the same dermal nerve bundle. This study has confirmed the existence of epidermal nerves in normal adult human skin, and presented a more clear picture than earlier. The difference between densities of epidermal nerves at different body areas implies area-specific functions of the intraepidermal nerve terminals. The observed intraepithelial nerve fibers may have a pain-perceiving role, however, also trophic or immunoregulatory roles can not be excluded.

Comparative analysis of numerical estimation methods of epithelial nerve fibers using tissue sections.

The proper assessment of neuron numbers in the nervous system during physiological and pathological conditions, as well as following various treatments, has always been an important part of neuroscience. The present paper evaluates three methods for numerical estimates of nerves in epithelium: I) unbiased nerve fiber profile and nerve fiber fragment estimation methods, II) the traditional method of counting whole nerve fibers, and III) the nerve fiber estimation method. In addition, an unbiased nerve length estimation method was evaluated. Of these four methods, the nerve length per volume method was theoretically optimal, but more time-consuming than the others. The numbers obtained with the methods of nerve fiber profile, nerve fragment and nerve fiber estimation are dependent on the thickness of the epithelium and the sections as well as certain shape factors of the counted fiber. However for those, the actual counting can readily be performed in the microscope and is consequently quick and relatively inexpensive. The statistical analysis showed a very good correlation (R > 0.96) between the three numerical methods, meaning that basically any method could be used. However, dependent on theoretical and practical considerations and the correlation statistics, it may be concluded that the nerve fiber profile or fragment estimation methods should be employed if differences in epithelial and section thickness and the nerve fibers shape factors can be controlled. Such drawbacks are not inherent in the nerve length estimation method and, thus, it can generally be applied.

Immunohistochemical demonstration of exocytosis-regulating proteins within rat molar dentinal tubules.

No morphologically defined synaptic structures have so far been detected between nerve terminals and the dentine-producing odontoblasts. Recent studies of the molecular mechanisms in neuronal exocytosis have identified several proteins that participate in synaptic-vesicle exocytosis. By localizing these proteins with immunohistochemical methods, information about the capacity for synaptic exocytosis should be obtained. Here, antibodies directed against some of the exocytosis-related proteins were used to investigate whether they are present in nerve fibers within the dentinal tubules in rat molars. Antibodies against synaptosome-associated protein of 25 kDa, Rab 3, synaptotagmin and synapsin all produced a punctuate staining pattern, suggesting that the proteins are accumulated in bouton-like elements. The results demonstrate that a set of exocytosis-related proteins is accumulated in the dentinal tubules, most probably within the intradentinal nerves. This finding is consistent with the hypothesis that intradentinal nerves can mediate efferent signals.

Proliferative activity in the juxtaradicular human periodontal ligament.

The aim of the present study was to evaluate cell proliferation, assessed by MIB 1, with respect to the type and the distribution of proliferating cells in the healthy juxtaradicular periodontal ligament (PDL) from completely formed human teeth. Immunohistochemical markers against vimentin, CD68 and S-100 were used to characterize cell type. The applicability of the immunohistochemical method on explants of human PDL was also evaluated. The results indicated that under physiological conditions, the majority of the proliferating cells in the PDL were mesenchymal cells predominantly located paravascularly in the middle third of the PDL. Furthermore, MIB 1 reacting with the Ki-67 antigen together with the avidin-biotin-complex technique was proved to be an efficient marker of cell proliferation in explants of human PDL.

Increased intraepithelial innervation in women with vulvar vestibulitis syndrome.

Women with vulvar vestibulitis syndrome (VVS) suffer from severe pain and discomfort in the area around the introitus at almost any stimulus that causes pressure within the vestibule. In spite of the severe sensory symptoms present in these women, the influence of the peripheral nerves in the vulvar vestibulum has not been clarified before. In this study the nerve supply in the vestibular mucosa in women with VVS and in healthy women free from vulvar symptoms has been revealed by PGP 9.5 immunohistochemistry. The results show a significant increase in the number of intraepithelial nerve endings in women with VVS, indicating an alteration in the nerve supply in the afflicted area.

Decreased innervation of the paraurethral epithelium in stress urinary incontinent women.

OBJECTIVE: To determine whether there is a difference in the innervation of the paraurethral vaginal epithelium between stress urinary incontinent women of fertile age and comparable controls. METHODS: Transvaginal biopsies close to the external orifice of the urethra were obtained from 11 stress urinary incontinent women and from ten comparable controls. The specimens were processed for indirect immunohistochemistry using protein gene product 9.5 (PGP 9.5) as a general neuronal marker. From each biopsy, ten randomly selected fields of 1 mm2 projected area were investigated and nerve fibre profiles were quantificated in a microscope equipped with light- and dark-field optics. RESULTS: Nerve fibre profiles/mm2 of projected epithelial area were significantly lower in the incontinent group than in the control group (P < 0.01). CONCLUSION: Our study indicates that stress urinary incontinent women have a significantly lower total innervation of the paraurethral vaginal epithelium than continent controls.

Healing of the root surface-associated periodontium: an immunohistochemical study of orthodontic root resorption in man.

The purpose of the present investigation was to study resorption and regeneration of periodontal tissues incident to orthodontic tooth movement, in particular cells resorbing the root surface and the subsequent regeneration of the periodontal epithelial network and forming reparative cementum. The study was carried out using a select number of immunohistochemical markers on extracted human teeth which had been treated orthodontically. The most striking finding in the resorbing areas was the presence of what appeared to be two populations of KP 1+ mononuclear cells located at a distance of 50-100 microns from the root surface and multinucleated cells in resorption lacunae in close contact with the root surface. KP 1+ has previously not been reported for odontoclasts. The mononuclear KP 1+ cells in the periodontal ligament may represent either precursors to odontoclasts or phagocytic scavenger cells of the macrophage lineage. The subsequent healing of the resorption lacunae was characterized by re-establishment of nervous, vascular and epithelial tissues as evidenced by S-100+ filamentous delicate structures, factor VIII+ vessels and cytokeratin+ clusters of cells, respectively. However, cytokeratin+ single cells in close contact with the unresorbed cementum did not re-appear within the healing period. Although the present results are not quantitative in nature, cementoblasts located in the vicinity of resorption lacunae, especially healing ones, appeared to show an up-regulation of epidermal growth factor (EGF) receptors. It may be suggested the intense positive staining for EGF receptors may be an expression of an auto- or paracrine stimulatory pathway increasing the rate of reparative cementum formation.

A screening of skin changes, with special emphasis on neurochemical marker antibody evaluation, in patients claiming to suffer from "screen dermatitis" as compared to normal healthy controls.

In the present study, facial skin from so-called "screen dermatitis" patients were compared with corresponding material from normal healthy volunteers. The aim of the study was to evaluate possible markers to be used for future double-blind or blind provocation investigations. Differences were found for the biological markers calcitonin gene-related peptide (CGRP), somatostatin (SOM), vasoactive intestinal polypeptide (VIP), peptide histidine isoleucine amide (PHI), neuropeptide tyrosine (NPY), protein S-100 (S-100), neuron-specific enolase (NSE), protein gene product (PGP) 9.5 and phenylethanolamine N-methyltransferase (PNMT). The overall impression in the blind-coded material was such that it turned out easy to blindly separate the two groups from each other. However, no single marker was 100% able to pin-point the difference, although some were quite powerful in doing so (CGRP, SOM, S-100). However, it has to be pointed out that we cannot, based upon the present results, draw any definitive conclusions about the cause of the changes observed. Whether this is due to electric or magnetic fields, a surrounding airborne chemical, humidity, heating, stress factors, or something else, still remains an open question. Blind or double-blind provocations in a controlled environment are necessary to elucidate possible underlying causes for the changes reported in this investigation.

Protein gene product 9.5-immunoreactive nerves and cells in human oral mucosa.

BACKGROUND: Current conflicting information on the innervation of the human oral cavity indicates technical problems such as different detectability of the neural structures according to the various staining methods used and difficulties in reproducibility. The possibility of intraoral regional differences has not been properly considered. METHODS: Human biopsies of mucosa from different intraoral regions were prepared for immunohistochemistry using protein gene product 9.5 (PGP 9.5; a marker for neuronal structures). RESULTS: Nerves were found consistently in all the biopsies. The neural pattern showed clear regional differences. Intraepithelial nerve fibers were found in the gingiva, labia, palate, within certain fungiform papillae, and in some salivary excretory ducts. Organized nerve endings were found in varying frequencies in all but one (sublingual) region, appearing as lamellar (Meissner-like), coiled or glomerular neural structures. Merkel cell-neurite complexes were observed in the buccal, gingival, and palatal epithelia. Immunoreactive cells with many similarities to Merkel cells but without a neural connection were also encountered. CONCLUSIONS: Conflicting results from earlier innervation studies of the oral cavity could be attributed to regional innervation differences. The distribution of the nerves also casts doubt on some of the present theories concerning the function(s) of intraoral nerves, such as the free nerve endings and the Merkel cell-neurite complexes.

Histological characteristics of peri-implant mucosa around Brånemark and single-crystal sapphire implants.

Soft tissues surrounding Brånemark titanium implants and single crystal sapphire implants were studied by conventional light- and transmission electron microscopy and by immunohistochemical markers for cytokeratin, protein S-100, Factor VIII and KP1. Histological sections of biopsies obtained from clinically healthy peri-implant mucosa were separated into a keratinized outer implant epithelium and an inner, non-keratinized epithelium, both immunoreactive towards cytokeratin. The inner implant epithelium terminated in a junctional epithelium, apically not a few cell layers thick. The cells adjacent to the implant showed a condensed cytoplasm, resembling hemidesmosomes. In the underlying connective tissue, rich in fibroblasts and factor VIII immunoreactive blood vessels, the bundles of collagen ran in different directions. S-100 immunoreactive nerve structures were more frequently found beneath the outer than the inner implant epithelium. Inflammatory cell infiltrates, some KP1 positive, were observed in the apical parts of the inner implant epithelium. S-100 positive Langerhans' cells were present mainly within the the outer implant epithelium. For the two implant systems, the techniques disclosed no qualitative structural differences in the adjacent soft tissues.