Control of Grain Boundary Location By Selective Nucleation Over Amorphous Substrates

A selective nucleation based crystal-growth-technique over amorphous substrates is originated. The method manipulates nucleation sites and periods and hence, controls the grain boundary location by modifing the substrate surface. In Si, small Si3 N4 nucleation sites are formed, 1–2 pm in diameter, 100 μm in period, over Sio2. One Si nucleus is formed exclusively in the small area of Si3 N4 by CVD. The highly faceted and periodically located nuclei grow over SiO2 up to 100 μm in diameter before impingement. A MOS-FET fabricated inside the island operates comparably to the bulk Si control

A randomized trial to identify optimal precurarizing dose of rocuronium to avoid precurarization-induced neuromuscular block

PURPOSE

The aim of this study was to examine the safe precurarizing dose of rocuronium required to avoid neuromuscular block after precurarization.

METHODS

Twenty-four female patients were randomly allocated into two groups of 12 patients each. General anesthesia was induced and maintained with remifentanil and propofol, and a laryngeal mask was inserted without the aid of a neuromuscular blocking agent. Patients were randomized to receive either 0.03 or 0.06 mg/kg rocuronium as a precurarizing dose. Neuromuscular block was monitored using acceleromyographic train-of-four (TOF) of the adductor pollicis muscle. Three minutes after the precurarization, all patients received suxamethonium 1.5 mg/kg and were graded on severity of fasciculations.

RESULTS

The average TOF ratio was kept above 0.9 even 3 min after precurarization with 0.03 mg/kg rocuronium. In contrast, in patients who received 0.06 mg/kg rocuronium, the ratios significantly decreased to 0.72 (0.14) [mean (SD), P < 0.004] and 0.68 (0.18) (P < 0.006) 2 min and 3 min after the precurarization, respectively. No visible muscle movement was observed following suxamethonium injection, except that one patient who received 0.03 mg/kg rocuronium showed very fine muscle movements of the fingertips.

CONCLUSION

Rocuronium at 0.06 mg/kg is an overdose for precurarization. The results of the present study demonstrate that a safe and effective precurarizing dose of rocuronium is 0.03 mg/kg.

Leg ulcer caused by Mycobacterium ulcerans ssp. shinshuense infection

BACKGROUND

An 81-year-old man presented with a skin ulcer on the left forearm caused by infection with Mycobacterium ulcerans ssp. shinshuense. The patient first noticed the subcutaneous nodule with an undermined ulcer and areola on the left forearm without any episode of trauma.

METHODS

The rod-shaped and acid-fast bacteria taken from the ulcerative lesion were positive for Ziehl-Neelsen staining. The bacterial colony was cultured on Ogawa slant egg medium at 28 degrees C.

RESULTS

A clinical diagnosis of Mycobacterium infection was made. For therapy, in addition to oral clarithromycin, topical sulfadiazine silver and hyperthermia were used. One month after starting treatment, topical treatment was changed to U-pasta (sucrose, povidone-iodine). Four months after the onset of the disease, bacterial colonies composed of scotochromogens were identified as Mycobacterium marinum by the DNA-DNA hybridization (DDH) method. The growth speed and characteristics of the bacterial colonies were different from those of Mycobacterium marinum.

CONCLUSIONS

This pathogenetic bacterium was finally identified as Mycobacterium ulcerans ssp. shinshuense by the polymerase chain reaction method and 16S rRNA gene sequencing. Nine months after the onset of the disease, the ulcer was re-epithelialized with a residual scar.

Multiple cutaneous squamous cell carcinomas in a patient with interferon gamma receptor 2 (IFN gamma R2) deficiency

Disseminated squamous cell carcinoma (SCC) of the skin is exceedingly rare in children. SCC occurs after immunodeficiency from immunosuppression in organ transplant recipients or patients with HIV infection or leukaemia, but has not been reported in primary immunodeficiencies other than epidermodysplasia verruciformis. Interferon gamma receptor 2 (IFN gamma R2) deficiency is an exceedingly rare primary immunodeficiency, conferring almost selective predisposition to mycobacterial diseases. A disseminated, cutaneous SCC is described that occurred in a patient homozygous for a novel frameshift deletion at positions 949 and 950 (949delTG) in the IFNGR2 gene. The patient first presented at 1 year of age with disseminated Mycobacterium avium infection, with later infections of atypical mycobacteria (Mycobacterium fortuitum and Mycobacterium porcium). At 17 years of age, the patient developed multifocal SCC lesions on the face and both hands. Histopathological examination revealed well differentiated SCC. Despite local tumour excision, multiple lesions occurred and a large SCC on the right arm required amputation. The patient died at 20 years of age of disseminated SCC. Inherited disorders of IFN gamma mediated immunity may predispose patients to SCC.

Immunohistochemical study of cytokeratin expression in nevus sebaceous

BACKGROUND

The histogenesis of nevus sebaceous (NS) is unclear.

METHODS

To elucidate the histogenesis of NS, cytokeratin (CK) profiles were examined immunohistochemically using 10 anti-keratin antibodies in the three stages of NS.

RESULTS

In the first stage, stratified differentiated keratins (CK1 and 10) were reduced, and basal keratin (CK14) was increased in the epidermis and primitive follicular structure (PFS). In the second stage, in addition to reduced CK1 and CK10 expressions and increased CK14 expression, CK17 expression was strongly expressed in the sebaceous ducts in proportion to the development of sebaceous gland. In the third stage, CK14, CK17 and CK19 were expressed in secondary tumors. CK16 was not detected throughout all stages of NS.

CONCLUSION

These results suggest that NS is not hyperproliferative but involves hamartomatous differentiation with undifferentiated keratins.

Primary cutaneous apocrine carcinoma arising within a congenital nevus: Keratins and filaggrin expression suggesting differentiation into the secretory cells of apocrine glands

Primary cutaneous apocrine carcinoma (PCAC) is a rare neoplasm of skin appendages. To determine the differentiation of apocrine carcinoma, we studied the expression of epithelial keratins and filaggrin immunohistochemically using 10 anti-keratin antibodies againt keratin (K) 1, 7, 8, 10, 14, 15, 16, 17, 18, 19 and the anti-filaggrin antibody. PCAC demonstrated strong positivity for K7, K8, K18 and K19. These keratins are distributed in secretory cells of normal apocrine glands. The tumor cells were negative for K14 and K17. The two keratins exist in myoepithelial cells in normal apocrine glands. Results suggest that PCAC shows differentiation into secretory cells of apocrine glands, although it does not differentiate into myoepithelial cells. K14 is also known as undifferentiated keratin, whereas K17 is considered to be a hyperproliferative keratin. Absence of the expression of K14 and K17 may reflect an indolent clinical course of PCAC.

[Optimum intubating dose of rocuronium for short duration surgery in adult patients]

BACKGROUND

The aim of this study was to examine optimum intubating dose of rocuronium in adult patients who had been scheduled for short duration surgery.

METHODS

Thirty patients were randomly assigned to receive rocuronium 0.4 mg x kg(-1), 0.5 mg x kg(-1) or 0.6 mg x kg(-1) during induction with propofol and fentanyl. Immediately after the adduction of thumb to the ulnar nerve stimulation could not be visually observed, the patients were intubated tracheally and the intubating conditions were evaluated. Thereafter, time to recover to train-of-four (TOF) counts of 4 was recorded during sevoflurane and nitrous oxide anesthesia.

RESULTS

Intubating conditions after rocuronium 0.5 and 0.6 mg x kg(-1) were all graded either excellent or good. In contrast, inadequate conditions for safe and easy tracheal intubation were observed in 60% of the patients receiving 0.4 mg x kg(-1). Time to spontaneous recover to the TOF counts of 4 correlated with the intubating doses of rocuronium.

CONCLUSIONS

For short duration surgeries, rocuronium 0.5 mg x kg(-1) was appropriate to perform safe tracheal intubation and minimize duration of action of rocuronium.

Restoration of peripheral blood T cell repertoire complexity during remission in advanced cutaneous T cell lymphoma

In advanced stages, cutaneous T cell lymphomas (CTCL) are associated with increased mortality from infections and also increased susceptibility to skin malignancies. In this study, we analyzed the complexity of the peripheral blood T cell repertoire with a sensitive b-variable (BV) complementarity-determining region 3 (CDR3) spectratyping analysis and flow cytometry in three-stage IV CTCL/Sezary syndrome patients who achieved complete clinical remission after therapy. The T cell repertoire of peripheral blood T cells before treatment was profoundly abnormal across multiple BV subfamilies. Following treatment, CDR3 spectratype patterns showed dramatic restoration of normal diversity and complexity. However, absolute CD4 counts across multiple BV families remained low for many months, even after identifiable circulating malignant T cell populations were eliminated. These data suggest that the diversity of the T cell repertoire can be recovered after successful treatment of even advanced CTCL.

Infusion requirements and reversibility of rocuronium at the corrugator supercilii and adductor pollicis muscles

BACKGROUND

The aim of this study is to compare the infusion rates required to maintain a constant neuromuscular block and the reversibility of rocuronium at the corrugator supercilii muscle (CSM) and the adductor pollicis muscle (APM).

METHODS

We randomly allocated 30 female patients into two groups of 15 patients each to monitor neuromuscular block at either the CSM or the APM. After induction of anaesthesia and laryngeal mask insertion, contraction of the CSM to the facial nerve stimulation or that of the APM to the ulnar nerve stimulation was quantified using an acceleromyograph during 1.0-1.5% end-tidal sevoflurane anaesthesia. All the patients received a bolus of 1 mg/kg rocuronium. When the first twitch (T1) of train-of-four (TOF) recovered to 10% of the control, rocuronium infusion was commenced and maintained at T1 of 10% of the control at the CSM or APM for 120 min. Immediately after rocuronium infusion was discontinued, the time required for 0.04 mg/kg neostigmine-facilitated recovery to a TOF ratio of 0.9 was recorded.

RESULTS

Rocuronium infusion dose after a lapse of 120 min was significantly larger in the CSM than in the APM [7.1 (2.3) vs. 4.7 (2.6) microg/kg/min; P=0.001]. The time for facilitated recovery was shorter in the CSM than in the APM [11.4 (3.8) vs. 16.2 (6.0) min; P=0.016].

CONCLUSION

A larger rocuronium infusion dose was required to maintain a constant neuromuscular block at the CSM. Neostigmine-mediated reversal was faster at the CSM.

Assessing the immune state of dogs suffering from pituitary gland dependent hyperadrenocorticism by determining changes in peripheral lymphocyte subsets

In order to evaluate the immune state of dogs suffering from pituitary-dependent hyperadrenocorticism (PDH), peripheral lymphocyte subsets were examined. Twenty seven PDH dogs and eight healthy control dogs were used in the current study. Eight healthy dogs served as the control group. Twenty seven PDH dogs were categorized into 4 groups based on their post serum cortisol concentrations by ACTH stimulation test: 2-5, excellent control (n = 8); 5-20, fair control (n = 7); >20, poor control (n = 4); and untreated (n = 8). Cell counts were executed with white blood cells (WBC), lymphocytes, CD3(+) (T lymphocytes), CD4(+) (Helper T lymphocytes), CD8(+) (Cytotoxic T lymphocytes), CD21(+) (B lymphocytes) cells in addition to calculating CD4(+)/CD8(+) ratio. Results indicated a significant difference in lymphocyte numbers and lymphocyte subset populations (CD3(+), CD4(+), CD8(+), and CD21(+) cells) between PDH and control dogs. Moreover, comparison of the PDH groups (excellent control; fair control; poor control; untreated) demonstrated that all groups had a significant decrease in lymphocytes numbers (CD3(+), CD4(+) and CD21(+) cell counts) as compared to control group. Meanwhile, no significant differences were observed in WBC counts and CD4(+)/CD8(+) ratio between groups. Furthermore, lymphocyte subset distribution in excellent control PDH dogs without concurrent disease (n = 4) better resembled that of control dogs as compared to PDH dogs with concurrent disease (n = 4). PDH dogs may be suffering from an immuno-depressed state as evidenced by significant differences in lymphocyte subset populations. Furthermore, treatment of both PDH and concurrent disease might improve lymphocyte subset distribution.

Comparison of three commercially available prescription diet regimens on short-term post-prandial serum glucose and insulin concentrations in healthy cats

Dietary therapy is an important treatment component for diabetes mellitus (DM). In this study, the impact of three different commercially available diet regiments (1 general use and 2 aimed for treating obesity and DM) on short-term post-prandial serum glucose and insulin concentrations of five healthy cats to better understand what impact each of these diets may have for diabetic cats. The diet regiments used in this study were as follows: C/D dry (General Use- Low protein, High fat, High carbohydrate, and Low fiber), M/D dry (DM- High protein, High fat, Low carbohydrate, and High Fiber), and W/D dry (DM- Low Protein, Low Fat, High Carbohydrate, and High Fiber). No significant difference in post-prandial serum glucose levels were observed with the C/D (84.6 +/- 1.5 mg/dl) and W/D (83.8 +/- 1.4 mg/dl) dry diets when compared to pre-prandial fasting levels (83.9 +/- 1.4 mg/dl). However, a significant reduction was observed with the M/D diet (78.9 +/- 0.8 mg/dl) which had 50-60% less carbohydrates than either C/D or W/D diet. Unlike what was observed with post-prandial glucose levels, an interesting pattern emerged with post-prandial insulin levels, which were increasing with W/D, C/D, and M/D diets in that order (1.1 +/- 0.2, 1.7 +/- 0.2, and 2.3 +/- 0.2 ng/ml respectively). Most surprising, though, was the fact that the W/D diet did not seem to stimulate insulin secretion as compared to pre-prandial levels (1.1 +/- 0.1 ng/ml) in healthy cats. Interestingly, the W/D diet had high levels of carbohydrate and low levels of protein. Coincidentally, the only diet (M/D) which had a significant reduction in post-prandial glucose also showed the highest increase in post-prandial insulin in healthy cats. Therefore, dietary amounts of carbohydrate, fat, protein and fiber can all have an individual impact on post-prandial glycemia and subsequent insulin requirement levels. Just as concepts regarding dietary management of people with DM are evolving, investigators are reassessing what constitutes the ideal diet for the diabetic feline. As such, having a better understanding for each dietary component, may lead us to better understand how we can synergize certain dietary components to aid in DM management.

Serum glycated albumin: Potential use as an index of glycemic control in diabetic dogs

Measurements of serum fructosamine, glycated hemoglobin, and glycated albumin (GA) complement serum glucose concentration for better management of diabetes mellitus (DM). Especially, the serum fructosamine test has long been used for diagnosing and monitoring the effect of treatment of DM in dogs. However, fructosamine tests are currently not performed in veterinary medicine in Japan. GA and fructoasmine levels have been shown to strongly correlate. However, the clinical implications of using GA remain to be elucidated. Therefore, the purpose of the current study was threefold: 1) Determine whether GA% is altered by acute hyperglycemia in normal dogs, simulating stress induced hyperglycemia; 2) Demonstrate that GA% does not dynamically change with diurnal variation of blood glucose concentration in diabetic dogs; and 3) Investigate whether GA% is capable of providing an index of glycemic control for 1-3 weeks in diabetic dogs as is the case with diabetic human patients. Our study demonstrated that serum GA% remains very stable and unaltered under acute hyperglycemic conditions (intravenous glucose injection) and in spite of diurnal variation of blood glucose concentration. Furthermore, serum GA% can reflect long-term changes (almost 1-3 weeks) in blood glucose concentration and the effect of injected insulin in diabetic dogs.

Protective role of interleukin-18 against Fas-mediated liver injury

Interleukin (IL)-18 plays an important role in the pathogenesis of several liver diseases as well as Fas-mediated apoptosis. However, the effects of IL-18 on Fas-mediated liver injury have not been well elucidated. Therefore, we examined the effects of IL-18 on Fas-mediated apoptosis in in vitro and in vivo experiments. We found that recombinant IL-18 protected mouse hepatocellular carcinoma cell lines, BNL5, from Fas-mediated apoptosis in a dose-dependent manner with up-regulation of both nuclear factor (NF) kappaB and X-linked inhibitors of apoptosis (XIAP). IL-18 transgenic (Tg) mice were also protected from Fas-mediated liver injury and this was further confirmed by histological study and TUNEL staining. In IL-18 Tg mice, up-regulation of XIAP and down-regulation of caspase 3 were observed after injection of anti-Fas, which was consistent with the in vitro findings. These results suggest that IL-18 suppresses Fas-mediated apoptosis of hepatocytes by up-regulation of NFkappaB and XIAP, following inhibition of caspase-3 activity. This observation raises the possibility that IL-18 could be a therapeutic strategy for Fas-mediated liver injury as a negative regulator of XIAP.

A case of Adamantiades-Behçet disease with ischemic optic neuritis (posterior optic neuropathy)

Adamantiades-Behçet disease (ABD) may present with cutaneous and ophthalmologic findings. A 29-year old woman complained of fever and general fatigue, along with erythema nodosum and vesiculo-pustular lesions on the legs, acneiform lesions, genital ulcerations and painful oral ulcers. She also complained of reduced visual acuity, visual disturbance and blurred vision in the left eye. Her left visual acuity was 6/20. Light reflex in the left eye was reduced. The relative afferent pupillary defect (RAPD) was positive in the left eye where a central scotoma was present. The vitreous was clear; the optic disc, macula, retina and iris were all normal. Uveitis was not observed. The patient was diagnosed with ischemic optic neuritis (posterior optic neuropathy) with ABD. Histopathological findings taken from a blister on the leg showed subepidermal bulla, dense dermal neutrophil infiltration, and extravasation of erythrocytes, suggesting leukocytoclastic vasculitis. She was treated orally with high-dose corticosteroids (methylprednisolone 500 mg/d) for three days. Her general condition and ophthalmic symptoms resolved completely. Optic neuropathy with ABD is very rare; we know of two previous cases [1, 2] of ABD with ischemic posterior optic neuritis.

Epidurally administered mepivacaine delays recovery of train-of-four ratio from vecuronium-induced neuromuscular block

BACKGROUND

The aim of this study was to examine the efficacy of epidurally administered mepivacaine on recovery from vecuronium-induced neuromuscular block.

METHODS

Eighty patients were randomly assigned to one of two study groups. They were either given epidurally a bolus of 0.15 ml kg(-1) of mepivacaine 2%, followed by repetitive injections of 0.1 ml kg(-1) h(-1) throughout the study, or were not given epidurally. General anaesthesia was induced and maintained with fentanyl, propofol and nitrous oxide. Neuromuscular block was induced with vecuronium 0.1 mg kg(-1) and monitored using acceleromyographic train-of-four (TOF) at the adductor pollicis. Patients in each treatment group were randomized to receive neostigmine 0.04 mg kg(-1) at 25% recovery of the first twitch of TOF or to recover spontaneously to a TOF ratio of 0.9. The effect of epidural mepivacaine on speed of spontaneous and facilitated recovery of neuromuscular function was evaluated.

RESULTS

The time from administration of vecuronium to spontaneous recovery to a TOF ratio of 0.9 was significantly longer in the epidural mepivacaine group [105.4 (14.2) min] as compared with the control group [78.5 (9.1) min, P < 0.01]. Neostigmine administered at 25% of control in T1 shortened recovery from neuromuscular block, however the time required for facilitated recovery to a TOF ratio of 0.9 in the epidural group was significantly longer than that in the control group [7.6 (1.6) min vs 5.8 (2.1) min, P < 0.01].

CONCLUSIONS

In clinical anaesthesia, it should be recognized that epidurally administered mepivacaine delays considerably the TOF recovery from neuromuscular block.

Necrobiotic xanthogranuloma with paraproteinemia; an atypical case

Necrobiotic xanthogranuloma (NXG) is a rare marker for paraproteinemia. An 86-year-old woman had a one year history of large red-yellow to brown annular plaques involving all limbs. Biopsies showed a non-palisading granuloma with numerous multinucleated giant cells showing prominent elastophagocytosis and extensive areas of necrobiosis throughout the entire dermis. Complete loss of elastic fibers was observed in the central atrophic area of an annular plaque. Small vascular thromboses were also present. Laboratory findings revealed paraproteinemia of IgG-lambda type. Immunohistochemical staining detected the presence of roughly equal numbers of IgG-lambda-and IgG-kappa-staining plasma cells in the dermis. We diagnosed NXG with paraproteinemia with monoclonal gammopathy (IgG-lambda type) of unknown significance.

Vitamins A and D are potent inhibitors of cutaneous lymphocyte-associated antigen expression

BACKGROUND

Cutaneous lymphocyte-associated antigen (CLA) is a surface glycoprotein expressed by skin-homing T cells. This carbohydrate moiety expressed on mucin-like surface glycoproteins, including P-selectin glycoprotein ligand 1 and CD43, confers binding activity to dermal endothelial E-selectin and is critical for T-cell recruitment to the skin. Vitamin A (retinoic acid [RA]) and the active form of vitamin D3 (1,25 dihydroxyvitamin D3 [1,25D(3)]) have been used to treat certain T cell-mediated inflammatory skin diseases, as well as cutaneous T-cell lymphomas; however, their effect on CLA expression has not been studied.

OBJECTIVE

We analyzed the effects of RA and 1,25D(3) on expression of CLA and other lymphocyte-homing receptors on human T cells.

METHODS

We cultured human T cells with 1,25D(3) and RA and analyzed the expression of CLA and other homing receptors. We also pretreated mice with either vitamin and then induced an antigen-dependent contact hypersensitivity response.

RESULTS

Both RA and 1,25D(3) downregulated expression of the CLA and, in parallel, functional E-selectin ligand. Whereas RA increased expression of the gut-homing receptor alpha4beta7 and reduced L-selectin expression, 1,25D(3) had no effect on other homing receptors. In an in vivo assay treatment with RA or 1,25D(3) downregulated the skin infiltration of effector CD4+ T cells.

CONCLUSION

These findings suggest that 1,25D(3) can selectively downregulate CLA expression without influencing lymphocyte migration patterns to other tissues.

Cytokeratin expression in squamous cell carcinoma arising from hidradenitis suppurativa (acne inversa)

We have studied cytokeratin (CK) expression in two cases of well-differentiated and poorly differentiated squamous cell carcinoma (SCC) arising from hidradenitis suppurativa (HS) (acne inversa). In both cases, type A (infundibular-like keratinized) epithelia were observed. In type A epithelia, CK 1 and 10 expressions were decreased, and CK 14 and 17 were detectable in the whole layers. CK 7, 8, 15, 16 and 18 were not detected in type A epithelia. In tumor nests of well-differentiated SCC, CK 1 and 10 expressions were downregulated, and CK 14 expression was upregulated. In tumor nests of poorly differentiated SCC, CK 1 and 10 were not expressed, but simple epithelial keratins (CK 8, 18 and 19) were expressed. These changes of CK expression are related to malignant transformation from the sinus tract (type A epithelium) in HS to SCC.

Cytokeratin and filaggrin expression in nevus comedonicus

To elucidate the pathogenesis of abnormal keratinization in nevus comedonicus, we performed an immunohistochemical study using antikeratin and antifilaggrin (filament-aggregating protein) antibodies. There were no significant differences between nevus comedonicus and normal skin in cytokeratin expression. Although filaggrin was only detected in the granular layer in open comedones, filaggrin was detected in both superficial cells and also intermediate cells in closed comedones, suggesting that filaggrin is involved in the formation of closed comedones. The disorder of terminal differentiation related to filaggrin may play a role in the pathogenesis of abnormal keratinization in nevus comedonicus.

Effect of supplementation of Agaricus mushroom meal extracts on enzyme activities in peripheral leukocytes of calves

To investigate the effect of Agaricus mushroom meal on the energy metabolism in animal tissues; plasma glucose, triglyceride, cholesterol and immunoreactive insulin (IRI) concentrations and activities of enzymes related to energy metabolism in plasma and peripheral leukocytes were measured in Japanese Black WagyuxHolstein F1 calves supplemented with Agaricus blazei Murill (A. blazei) extract in milk-replacer at the dose of 60g/head/day for 4 weeks. Activities of malate dehydrogenase and aspartate aminotransferase in cytosol and glutamate dehydrogenase in mitochondria, and the malate dehydrogenase/lactate dehydrogenase ratio in cytosol in peripheral leukocytes of calves with A. blazei were significantly higher than those in control calves without A. blazei. It was concluded that supplementation of Agaricus mushroom meal extract was effective in activation of enzymes related to energy metabolism in peripheral leukocytes of calves.

Pinkus tumor may originate from intraepidermal eccrine ducts and proliferate in the dermis

To clarify the histopathogenesis of Pinkus tumor (fibroepithelial basal cell carcinoma, FEBCC), we have studied cytokeratin (CK) expression in FEBCC using ten different anti-keratin antibodies against CK 1, 7, 8, 10, 14, 15, 16, 17, 18 and 19. Tumor nests consisted of two epithelial components: duct-like structures and basaloid cells of anastomosing strands. In duct-like structure, CK 1, 10, 14, 16, 17 and 19 were detected. CK expression of duct-like structure showed the hyperproliferative state of eccrine intraepidermal ducts. In basaloid cells of anastomosing strands, CK 14 and 17 were detectable. These results suggested that duct-like structure originates from the intraepidermal duct and proliferates to spread in the dermis.

Influence of attachment wear on retention of mandibular overdenture

The aims of this study were: (i) to evaluate and compare retention of two-teeth (implant) supported mandibular overdenture with either stud or magnetic attachments during linear (axial) and rotational (paraxial) dislodgements; (ii) to compare retentive properties before and after wear simulation. The test group consisted of five magnetic and four stud overdenture attachments (n = 12 specimens for each attachment type). Retention in axial direction was evaluated on one-tooth (implant) model by measuring maximum retentive force (N) and range of retention (mm) during the linear dislodgement. Retention in the paraxial direction was evaluated on mandibular-overdenture model by measuring the maximum retentive force (N) during three types of rotational dislodgements - anterior, lateral and posterior. The minimum number of cycles required to simulate wear was determined by special wear test. Afterwards, the wear was simulated in the test group, and retention in axial and paraxial directions was measured again.

STATISTICAL ANALYSIS

one-way anova, Scheffe post hoc and paired-samples t-tests (P < 0.05). Initially, studs had higher retention (4-11 N) than magnets (4.5-6 N) in axial direction. After the wear simulation, it had decreased from 76% to 48% for some of the studs and had become similar to the retention of magnetic attachments. Magnets had lower retention range (0.2-0.3 mm) than studs (0.5-1.1 mm). Studs provided similar or higher retention in paraxial directions than magnetic attachments both before and after wear simulation. Retentive properties of magnets decreased mostly with posterior rotational dislodgement. Retentive properties of stud overdenture attachments were less constant.