An Immunohistochemical Study on the Role of Oxidative and Nitrosative Stress in Irradiated Skin.

BACKGROUND/AIM: The effects of ionizing radiation through the generation of free radicals, reactive aldehydes, and other oxidative and nitrosative by-products account for skin injuries as side effects of radiation therapy (RT). This study aims to identify cellular pathways in oxidative and nitrosative stress in irradiated skin using well-established marker proteins in an immunohistochemical analysis. MATERIALS AND METHODS: Tissue specimens of 51 patients were obtained during operative access to the neck. Twenty patients (39.2%) received RT prior to the surgical intervention. Immunohistochemical analysis of stable degradation products of reactive oxygen and nitrogen species (RONS), 3-nitrotyrosine, 8-isoprostane, phosphorylated AKT (p-AKT), and phosphorylated extracellular signal-regulated kinase (p-ERK) was performed in specimens which were exposed to RT and those without a history of RT. RESULTS: Immunohistochemical staining showed a significantly increased expression of nitrotyrosine in superficial and basal epidermal regions of interest (ROI), p-AKT in all epidermal ROI, and p-ERK in all the investigated epidermal and dermal ROI, as well as in an overall analysis. No significance could be detected in immunostaining against isoprostane. DISCUSSION: This study summarizes the influence of RONS in RT. Moreover, a detailed histological analysis was able to identify epidermal ROI as a main starting point of RONS in irradiated skin. Even though the role of RONS in high-dose therapeutic radiation remains a subject for further research, these data underlines the crucial role of RONS in high-dose radiation.

The impact of the new scene drug "crystal meth" on oral health: a case-control study.

OBJECTIVE: The use of methamphetamine (MA), a highly addictive stimulant, is rapidly increasing, with MA being widely abused as the scene drug "Crystal Meth" (CM). CM has been associated with severe oral health effects, resulting in so-called "Meth mouth". This term appeared for the first time in 2005 in the literature and describes the final complex of symptoms including rampant caries, periodontal diseases and excessive tooth wear. The aim of this study was to investigate the effects of chronic CM abuse on teeth and intraoral tissue with respect to potential symptoms of Meth mouth. MATERIALS AND METHODS: In cooperation with two centres for addiction medicine, we performed clinical intraoral investigations in 100 chronic CM users and 100 matched-pair controls. We undertook a caries and periodontal examination by using the clinical parameters DMF-T/DMF-S, bleeding on probing index (BOP) and periodontal screening index (PSI) and tested individual oral hygiene by using approximal space plaque index (API). All clinical data were analysed by the t test for independent samples. RESULTS: We found significantly larger numbers of caries (p < 0.001) and higher levels of gingival bleeding (p < 0.001) and periodontal disease (p < 0.001) among CM users. Oral hygiene was significantly lower in CM users (p < 0.024). CONCLUSION: Chronic CM use can lead to extensive potential damage within the intraoral cavity. When CM is used over a long period of time and in the absence of treatment, clinical symptoms in terms of Meth mouth syndrome cannot be excluded. CLINICAL RELEVANCE: Based on our results, we recommend a specific prevention and therapeutic concept including educational campaigns for MA users and specialized dental care for CM patients.

Sympathomimetic effects of chronic methamphetamine abuse on oral health: a cross-sectional study.

BACKGROUND: Methamphetamine, a highly addictive sympathomimetic stimulant, is currently widely abused worldwide and has been associated with devastating effects on oral health, resulting in the term "meth mouth". However, "meth mouth" pathology is primarily based on case reports with a lack of systematic clinical evaluation. Therefore, we have conducted a systematic study to investigate (1) the pharmacological impact of methamphetamine on oral health with regard to saliva function, including the parameters saliva flow rate and total saliva production (ml/5 min) and the buffering capacity of saliva; (2) the contribution of the symptoms of bruxism and muscle trismus to potential oral health damage. METHODS: We assessed the data of 100 chronic methamphetamine abusers and 100 matched-pair comparison participants. Primarily, we conducted an anamnesis with all methamphetamine abusers with regard to saliva dysfunctions, jaw clenching and pain in the temporomandibular joint. Subsequently, in the first part of the clinical enquiry, we tested the saliva flow rate and the total saliva production (ml/5 min) by using the sialometry method and the buffer capacity of saliva by determining the pH-value. In the second part of the clinical enquiry, we evaluated bruxism symptoms with respect to generalized tooth attrition, dentine exposure and visible enamel cracks and examined a potential muscle trismus by measuring the maximal opening of the mouth. RESULTS: The majority of methamphetamine abusers reported a dry mouth (72 %) and jaw clenching (68 %). Almost half of all methamphetamine abusers experienced pain in the temporomandibular joint (47 %). With regard to the clinical findings, methamphetamine abusers showed significantly lower total saliva production (ml/5 min) (p < 0.001), lower pH-values of their saliva (p < 0.001) and more bruxism symptoms (p < 0.001). However, we found no relevant trismus symptoms on comparing the two groups (p > 0.05). CONCLUSIONS: The sympathomimetic effects of chronic methamphetamine abuse may lead to dry mouth and extensive bruxism and therefore can increase the risk for caries decay, periodontal lesions and tooth wear. Furthermore, a significant decline of saliva buffer capacity in methamphetamine abusers may trigger the risk for dental erosions. Methamphetamine abusers and practitioners should be aware of these symptoms.

The value of perioperative antibiotics on the success of oral free flap reconstructions.

The subject of the presented study was to monitor and compare problems and outcomes of reconstructive surgery with microvascular free flaps in the head and neck region between groups of patients treated with perioperative antibiotics and a group of patients without antibiotics. Patients requiring oral reconstructive surgery following cancer resections with microvascular free flaps were prospectively evaluated (2007-2012). Antibiotic therapy was started 30 min before the operation and administered for 10 days. Three hundred and fifty patients were included (208 male, 59.4%; 142 female, 40.6%; mean age 59.8 ± 13.2 years). 330 patients received perioperative antibiotics. Twenty patients (5.7%) who received no antibiotics for specific reasons served as the control group. Wound infections developed in 33 of 122 patients (27%) who received benzylpenicillin, 17 of 88 patients (19.3%) who received amoxicillin combined with sulbactam and 25 of 120 patients (20.8%) who received cefuroxime. Ten patients (50%) who did not receive antibiotics developed wound infections. Receiving no antibiotics or penicillin showed no benefit (P = 0.11). Those receiving cefuroxime showed significantly lower incidence of wound infections (P = 0.034; risk decreased by the factor 2.88). The use of amoxicillin combined with sulbactam showed the lowest rate of wound infections (P = 0.018; risk decreased by the factor 3.46). The use of amoxicillin combined with sulbactam appears to be the most appropriate prophylactic antibiotic followed by cefuroxime in oral microsurgical free flap reconstructions. These data may serve as a guide until a controlled multicenter prospective trial is performed comparing newer antibiotics against current standards.

Head and neck salivary gland carcinomas--elective neck dissection, yes or no?

PURPOSE: Surgical resection and subsequent neck dissection (ND) in cases of clinically positive lymph nodes is an accepted primary treatment strategy for salivary gland carcinomas. Because of uncertainty in the extent of lymphogenic metastasis, the authors advocate a strategy of surgical resection and elective ND (END) for all patients. The authors evaluated their treatment by estimating the frequency of metastatic disease and identifying factors associated with an increased risk for metastatic disease. MATERIALS AND METHODS: A retrospective cohort study was implemented using patient data obtained from the university's interdisciplinary board for head and neck tumors. Data were screened for age, gender, tumor entity, localization, grade, and TNM Classification of Malignant Tumors (by UICC, International Union Against Cancer) status. Statistical analysis was performed to identify possible predictors of lymph node metastasis. Nodal status groups (N(+) and N0) were compared with respect to age by t tests; other comparisons involved χ(2) tests. RESULTS: Ninety-four patients (50% female, 50% male; mean age, 59.12 yr) were identified, of whom 87 had an indication for END. On postsurgical histopathologic examination, 34 (39%; 17 male, 17 female) were diagnosed with N(+). Statistical analysis for nodal status produced explorative P values (age, P = .001; gender, P = .792; anatomic region, P = .114; tumor entity, P = .854; tumor status, P = .263; grade, P = .000). CONCLUSION: All studied malignancies were capable of lymph node dissemination. Therefore, no reliable preoperative predictors for lymphogenic metastasis are currently identifiable. Because of difficulties in safely predicting lymphogenic metastasis and the high rate of N(+) results on postoperative examination, the authors strongly advise END for all patients with salivary gland carcinoma.

Secondary maxillofacial reconstruction with the radial forearm free flap: a standard operating procedure for the venous microanastomoses.

BACKGROUND: The radial forearm free flap (RFFF) is commonly used in reconstructive surgery. With respect to the maxillofacial region, several venous anastomotic techniques (e.g., single or double anastomoses) have been described, but the debate as to which alternative is preferable is ongoing. A complicating factor is the unpredictable anatomical situation in patients undergoing secondary operation. No recommendations are available for the surgical strategy in such cases. We present a standard operating procedure (SOP) applicable for secondary reconstructions, postulating double anastomoses as the method of choice, and evaluate its efficacy. METHODS: The following parameters were retrospectively analyzed for 120 patients with secondary (41; 34.2%) or primary (79; 65.8%) reconstruction following the instructions of SOP and compared between the study groups: age; sex; history of radiotherapy; side of the donor arm; flap size; preparation and use of the cephalic vein and reasons for its non-inclusion; included venae comitantes; recipient veins; arterial anastomoses; revisions, flap survival, and mortality within thirty days after operation. RESULTS: The method of choice was applicable in 26 (63.4%) secondary and 52 (65.8%) primary reconstructions (no difference; P = 0.841), resulting in 100% flap viability in both groups. In the remaining cases, single venous anastomoses were performed, resulting in 73.3% flap viability in secondary and 100% in primary reconstructions. Flap survival in secondary reconstructions was significantly higher when double anastomoses were conducted (P = 0.012). CONCLUSIONS: The results suggest the necessity of double venous anastomoses in secondary maxillofacial reconstructions with RFFF.

Expression of host defence peptides in the lip vermilion mucosa during early infancy.

Emerging resistance to antibiotics has become a major problem. Host defence peptides (HDPs), which are effector molecules of the innate immune system, show broad antimicrobial activity. Synthetic derivates are currently being investigated as new anti-infectious agents. In infants, the use of conventional antibiotics is limited to a few substances because of adverse reactions. The new HDP substances might become alternatives to conventional antibiotics, but knowledge of the physiological quantities of the HDPs in infants is essential because of a narrow therapeutic index of currently available derivates. This study compares the mRNA levels of five major HDPs between infants and adults to test the hypothesis that HDP gene expression differs between these groups. Expression profiles of human beta-defensin (hBD)-1, hBD-2 and hBD-3, psoriasin and RNase 7 were assessed in the lip vermilion mucosa of infants (n = 15) and adult controls (n = 15) using real-time polymerase chain reaction. A significantly lower expression of hBD-2 (P = 0.043), hBD-3 (P = 0.014) and psoriasin (P = 0.018) was found in infants. No difference between the groups was noted with respect to transcript levels of hBD-1 and RNase 7. In conclusion, several HDPs are expressed at lower levels in infants, but not all. The results emphasize the need to adjust the dose of agents based on the specific HDP level for the treatment of infantile infections.

NOS1-, NOS3-, PIK3CA-, and MAPK-pathways in skin following radiation therapy.

BACKGROUND: Essential molecular pathways such as the MAPK pathway, NO system, or the influence of PIK3CA as an oncogene are known to regulate fundamental signalling networks. However, few knowledge about their role in the occurrence of wound healing disorders (WHD) following radiation therapy (RT) exists. This study aims to evaluate the expression profiles of specific molecular pathway marker genes. METHODS: Expression profiles of the genes encoding MAPK, NOS1, NOS3, and PIK3CA were analyzed, by RT-PCR, in specimens from patients with and without a history of RT to the head and neck. Clinical data on the occurrence of cervical WHDs were analyzed. RESULTS: Expression analysis of patients with postoperative WHDs revealed a significant increase in MAPK expression compared to the control group without occurrence of postoperative WHDs. PIK3CA showed a significantly increased expression in patients with a history of RT. Expression analysis of all other investigated genes did not reveal significant differences. CONCLUSIONS: This current study is able to show the influence of RT on different molecular pathways. This underlines the crucial role of specific molecular networks, responsible for the occurrence of long-term radiation toxicity such as WHDs. Additional studies should be carried out to identify possible starting points for therapeutic interventions.

Evaluation of methamphetamine-associated socioeconomic status and addictive behaviors, and their impact on oral health.

BACKGROUND: Chronic methamphetamine abuse can lead to multiple health hazards. In particular, the substance is associated with devastating effects on oral health including symptoms such as rampant caries, gingiva inflammation, and xerostomia, whereby the term "Meth Mouth" occurs in the current literature. However, "Meth Mouth" pathology is primarily described on the basis of individual cases or has been evaluated without consideration of the mass of potential influencing factors. Therefore, we have conducted a systematic study to investigate the effects of accompanying factors and circumstances on oral health in cases of chronic methamphetamine abuse. METHODS: In cooperation with two centers for addiction medicine, we assessed the data of 100 chronic methamphetamine users and 100 matched-pair controls between March 2012 and November 2013. We investigated their socioeconomic status, details of methamphetamine consumption behavior, collateral consumption of sugar beverages, nicotine alcohol, and other addictive substances including cannabis, opioids, other stimulants, and hallucinogens, and dental care. RESULTS: We found considerably greater unstable social circumstances, a high collateral consumption of substances with pathogenic potential for the stomatognathic system, and significantly poorer dental care in the methamphetamine-user group. CONCLUSIONS: Various factors have to be considered with regard to methamphetamine use and its influence on oral health. These factors can trigger potential damage by the drug methamphetamine possibly leading to the symptoms of "Meth Mouth", and should be considered in prevention and therapy strategies.

An expression analysis of markers of radiation-induced skin fibrosis and angiogenesis in wound healing disorders of the head and neck.

BACKGROUND: Radiation-induced fibrosis (RIF) is one of the severe long-term side effects of radiation therapy (RT) with a crucial impact on the development of postoperative wound healing disorders (WHD). The grades of fibrosis vary between mild to severe depending on individual radiosensitivity. In this study, we have investigated the molecular pathways that influence RIF and have correlated data from immunohistochemistry (IHC) for von -Willebrand Factor (vWF) and from Real-Time Polymerase Chain Reaction (RT-PCR) concerning markers such as Transforming Growth Factor (TGF)-ß 1, and vWF, with clinical data concerning the occurrence of WHD during follow-up. METHODS: Expression profiles of the genes encoding TGF-ß 1, vWF, and α-procollagen (PC) were analyzed, by RT-PCR, in specimens from patients with (n = 20; 25.6 %) and without (n = 58; 74.4 %) a history of previous RT to the head and neck. Moreover, IHC against vWF was performed. Clinical data on the occurrence of cervical WHDs were analyzed and correlated. RESULTS: A statistically significant increase in the expression profiles of α-PC and TGF-ß 1 was observed in previously irradiated skin samples (occurrence of RT >91 days preoperatively). vWF showed a statistically significant increase in non-irradiated tissue. Moreover, analysis of expression profiles in patients with and without WHDs during follow-up was performed. IHC showed a reduced amount of vessels and structural changes in epidermal tissue post-RT. CONCLUSIONS: The expression of markers of fibrosis and angiogenesis was analyzed in order to gain insight into molecular pathways that account for structural changes in irradiated skin and that eventually lead to WHDs. The results are congruent with reports from the literature and are a possible starting point for further research, as anti-TGF-ß 1 treatment, for example, could represent new therapeutic opportunities in the management of previously irradiated patients.

Development of a haptic model for teaching in reconstructive surgery--the radial forearm flap.

OBJECTIVES: The great value of the radial forearm flap (RFF) for reconstructive surgery stresses the importance of developing effective teaching methods. Our aim was to develop a realistic anatomic model that concisely simulates vital surgical steps while offering a haptic and visual experience. It should be cost-effective, easy to use, reusable, and quick to set up. MATERIALS AND METHODS: The development commenced by constructing a prototype presenting basic features. Together with photographic surgery documentation, it served as a blueprint for the advanced model. The flap-raising process was condensed into the 6 most important steps to illustrate the procedure concisely and chronologically. RESULTS: Our final version consists of polyurethane, and a customized forearm flexor muscle model serves as the basic structure. Diverse plasticizers give different degrees of hardness to mimic anatomic structures. Special didactic features of the model include a movable elastic ramus superficialis nervi radialis. The flap island is attachable/detachable by a patrix/matrix mechanism. The brachioradialis muscle is elastic and detachable, and the fascia antebrachii is additionally severable. Vessels can be disconnected, and the removable forearm skin features a wave-shaped incision for the flap pedicle. To investigate the didactic benefit of the RFF model, we used it in a teaching course for medical students. The group receiving teaching supported by the RFF model showed a statistically significant improvement of knowledge (P = 0.007) in comparison with the group solely receiving a standard lecture supported by surgery images. CONCLUSIONS: In our opinion, the RFF model is an excellent compromise with regard to realism, didactic benefit, and cost-/time-effectiveness and has proven successful in the teaching of medical students.

Can tissue spectrophotometry and laser Doppler flowmetry help to identify patients at risk for wound healing disorders after neck dissection?

OBJECTIVE: Microcirculation and oxygen supply in cervical skin were measured with an optical, noninvasive method in patients with or without radiotherapy before neck dissection. The course of wound healing was monitored after the surgical procedure to identify predictive factors for postoperative wound healing disorders. STUDY DESIGN: Tissue spectrophotometry and laser Doppler flowmetry were used to determine capillary oxygen saturation, hemoglobin concentration, blood flow, and blood velocity at 2-mm and 8-mm depths in the cervical skin of 91 patients before neck dissection in a maxillofacial unit of a university hospital in Munich, Germany. Parameters were evaluated for differences between patients with irradiation (24) and without (67) and patients with wound healing disorders (25) and without (66) (univariate or multivariate statistical analyses). RESULTS: Velocity at 2 mm was lower in irradiated skin (P = .016). Flow at 2 mm was higher in patients with wound healing disorders (P = .018). CONCLUSIONS: High flow values could help to identify patients at risk for cervical wound healing disorders.

Immunolocalization of antimicrobial and cytoskeletal components in the serous glands of human sinonasal mucosa.

Secretory cells in the seromucous glands of paranasal sinuses secrete antibacterial proteins for innate immune mucosal integrity. We studied the localization of antimicrobial and cytoskeletal components of the human seromucous glands and respiratory epithelium of the maxillary sinus and the ethmoidal cells by immunohistochemical methods. The presence of a variety of defense proteins such as lysozyme, lactoferrin, cathelicidin, and defensin-1, -2, -3 point to a crucial role in the immune defense for the respiratory tract. Cytoskeletal proteins such as actin, myosin 2, cytokeratin 7 and 19, α- and ß-tubulin, investigated for the first time in glands of paranasal sinuses, showed a stronger expression at the apical and lateral cell membrane. The localization of the cytoskeletal proteins might point to their participation in exocrine secretory processes and stabilizing effects.

Evaluation of human amniotic membrane as a wound dressing for split-thickness skin-graft donor sites.

Human amniotic membrane (HAM) has been used as a biomaterial in various surgical procedures and exceeds some qualities of common materials. We evaluated HAM as wound dressing for split-thickness skin-graft (STSG) donor sites in a swine model (Part A) and a clinical trial (Part B). Part A: STSG donor sites in 4 piglets were treated with HAM or a clinically used conventional polyurethane (PU) foil (n = 8 each). Biopsies were taken on days 5, 7, 10, 20, 40, and 60 and investigated immunohistochemically for alpha-smooth muscle actin (αSMA: wound contraction marker), von Willebrand factor (vWF: angiogenesis), Ki-67 (cell proliferation), and laminin (basement membrane integrity). Part B: STSG donor sites in 45 adult patients (16 female/29 male) were treated with HAM covered by PU foam, solely by PU foam, or PU foil/paraffin gauze (n = 15 each). Part A revealed no difference in the rate of wound closure between groups. HAM showed improved esthetic results and inhibitory effects on cicatrization. Angioneogenesis was reduced, and basement membrane formation was accelerated in HAM group. Part B: no difference in re-epithelialization/infection rate was found. HAM caused less ichor exudation and less pruritus. HAM has no relevant advantage over conventional dressings but might be a cost-effective alternative.

Repair of oronasal fistulae by interposition of multilayered amniotic membrane allograft.

BACKGROUND: Oronasal fistulas are a frequent complication after cleft palate surgery. Numerous repair methods have been described, but wound-healing problems occur often. The authors investigated, for the first time, the suitability of multilayered amniotic membrane allograft for fistula repair in a laboratory experiment (part A), a swine model (part B), and an initial patient series (part C). METHODS: In part A, one-, two-, and four-layer porcine and human amniotic membranes (n = 20 each) were fixed in a digital towing device and the force needed for rupture was determined. In part B, iatrogenic oronasal fistulas in 18 piglets were repaired with amniotic membrane allograft, autofetal amniotic membrane, or small intestinal submucosa (n = 6 each). Healing was evaluated by probing and visual inflammation control (no/moderate/strong) on postoperative days 3, 7, 10, and 76. Histological analysis was performed to visualize tissue architecture. In part C, four patients (two women and two men, ages 21 to 51 years) were treated with multilayered amniotic membrane allograft. RESULTS: In part A, forces needed for amniotic membrane rupture increased with additional layers (p < 0.001). Human amniotic membrane was stronger than porcine membrane (p < 0.001). In part B, fistula closure succeeded in all animals treated with amniotic membrane with less inflammation than in the small intestinal submucosa group. One fistula remained persistent in the small intestinal submucosa group. In part C, all fistulas healed completely without inflammation. CONCLUSIONS: Amniotic membrane is an easily available biomaterial and can be used successfully for oronasal fistula repair. The multilayer technique and protective plates should be utilized to prevent membrane ruptures. CLINICAL QUESTION/LEVEL OF EVIDENCE: Therapeutic, V.

Secondary correction of posttraumatic orbital wall adhesions by membranes laminated with amniotic membrane.

The objective of the study was to find out if human amniotic membrane could be used for corrective surgery after trauma to the orbital wall. Because of its proposed antiadhesive qualities, it seemed to be potentially suitable. We studied 8 men (mean age 37 (range 19-74) years) who had deficient ocular movement after fractures of the orbital floor. Five of them had already been operated on. Inclusion criteria were trauma dating back more than 4 months and a soft tissue stricture in the orbital floor diagnosed by magnetic resonance imaging. Patients were treated secondarily with lysis of adhesions and insertion of allogeneic human amniotic membrane laminated on to polyglactin 910/polydioxanone foil, which functioned as the carrier material. Patients were followed up for 3 months, by which time disorders of motility of the ocular bulb had disappeared completely in 5. Two patients had improved motility and a reduction in both their subjective and objective symptoms. One patient had no improvement. The considerable reduction in adhesions and scarring after insertion of the membrane confirms previous assumptions, according to which the epithelial side of the human amniotic membrane has an antiadhesive effect because of its smooth surface.

Reduction of donor site morbidity of free radial forearm flaps: what level of evidence is available?

BACKGROUND: The radial forearm free flap (RFFF) is the most commonly used free flap in head and neck reconstructive surgery. However, despite excellent results with respect to the site of reconstruction, donor site morbidity cannot be neglected. This review summarizes the current state of knowledge and analyzes the level of evidence with regard to perioperative management of the reduction of RFFF donor site morbidity. METHODS: The medical Internet source PubMed was screened for relevant articles. All relevant articles were tabulated according to the levels of scientific evidence, and the available methods for reduction of donor site morbidity are discussed. RESULTS: Classification into levels of evidence reveals 3 publications (1.5%) with level I (randomized controlled trials), 29 (14.0%) with level II (experimental studies with no randomization, cohort studies, or outcome research), 3 (1.5%) with level III (systematic review of case-control studies or individual case-control studies), 121 (58.7%) with level IV (nonexperimental studies, such as cross-sectional trials, case series, case reports), and 15 (7.3%) with level V (narrative review or expert opinion without explicit critical appraisal). Thirty-five (17.0%) articles could not be classified, because they focused on a topic other than donor site morbidity of the RFFF. CONCLUSIONS: Although great interest has been expressed with regard to reducing the donor site morbidity of the workhorse flap in microvascular reconstruction procedures, most publications fail to provide the hard facts and solid evidence characteristic of high-quality research.

The human submandibular gland: immunohistochemical analysis of SNAREs and cytoskeletal proteins.

Submandibular acinar glands secrete numerous proteins such as digestive enzymes and defense proteins on the basis of the exocrine secretion mode. Exocytosis is a complex process, including a soluble NSF attachment protein receptor (SNARE)-mediated membrane fusion of vesicles and target membrane and the additional activation of cytoskeletal proteins. Relevant data are available predominantly for animal salivary glands, especially of the rat parotid acinar cells. The authors investigated the secretory molecular machinery of acinar (serous) cells in the human submandibular gland by immunohistochemistry and immunofluorescence and found diverse proteins associated with exocytosis for the first time. SNAP-23, syntaxin-2, syntaxin-4, and VAMP-2 were localized at the luminal plasma membrane; syntaxin-2 and septin-2 were expressed in vesicles in the cytoplasm. Double staining of syntaxin-2 and septin-2 revealed a colocalization on the same vesicles. Lactoferrin and α-amylase served as a marker for secretory vesicles and were labeled positively together with syntaxin-2 and septin-2 in double-staining procedures. Cytoskeletal components such as actin, myosin II, cofilin, and profilin are concentrated at the apical plasma membrane of acinar submandibular glands. These observations complement the understanding of the complex exocytosis mechanisms.

Quantitative comparison of the expression of antimicrobial peptides in the oral mucosa and extraoral skin.

Antimicrobial peptides (AMP) defend epithelial surfaces against pathological micro-organisms. We know of no comparison of their expression between the oral mucosa and extraoral epithelium, but knowledge of differences in their quantities is of interest, possibly as a starting point for new treatments. Expression of AMP human beta-defensin (hBD)-1/-2/-3 and psoriasin in the oral mucosa and extraoral epithelium of the head and neck were measured by real-time polymerase chain reaction (RT-PCR) (n=14), immunohistochemistry (n=6), and western blot (n=8). RT-PCR showed that all the genes investigated were expressed significantly more in the oral mucosa than in the skin (hBD-1: p=0.002; hBD-2: p=0.006; hBD-3: p=0.035; psoriasin: p=0.02). Immunohistochemistry and western blot showed differential concentrations of proteins: hBD-2 (p=0.021) and hBD-3 (p=0.043) were pronounced in the oral mucosa, whereas psoriasin was raised in the extraoral skin (p=0.021). There was no difference in protein concentrations for hBD-1 (p=0.08). The observed differences in the expression of AMP may be important for new treatments such as topical application of AMP derivatives.

Use of microvascular flap technique in older adults with head and neck cancer: a persisting dilemma in reconstructive surgery?

OBJECTIVES: To compare perioperative problems and outcomes of reconstructive surgery with microvascular flaps of a group of older (≥ 70) and younger adults (20-69). DESIGN: Prospective clinical cohort study. SETTING: Maxillofacial surgical unit of a university teaching hospital in Munich, Germany. PARTICIPANTS: Two hundred fifteen people with head and neck carcinoma (older: n = 54, mean age 75.8, range 70-96; younger: n = 161, mean age 55.5, range 20-69) who underwent surgery between 2007 and 2009. MEASUREMENTS: Participant characteristics: age, sex, American Society of Anesthesiologists (ASA) status, tumor type, preoperative radiation or chemotherapy, medical comorbidities. Surgical variables: flap type, type of reconstruction (primary/secondary), length of operation (minutes). Postoperative variables: length of stay (minutes) on intensive care unit (ICU), reasons for ICU stay longer than 1,500 minutes (surgical or medical), length of hospitalization (days), and reasons for hospitalization longer than 20 days (surgical or /medical). Short-term outcome within 30 days: revisions, flap success, overall complication rate, mortality. RESULTS: Older adults had a higher ASA class (P < .001) and shorter duration of surgery (P = .02). Age as an independent factor prolonged stay on ICU (P = .008) and was associated with a higher complication rate (P = .003) but had no influence on length of hospitalization, flap success, need for revisions, or mortality. CONCLUSION: Although higher rates of peri- and postoperative difficulties must be expected when microvascular reconstructive surgery is considered for older adults, careful surgical technique, adequate postoperative surveillance, and immediate management of complications can facilitate outcomes comparable with those for younger adults.