Use of straight and curved 3-dimensional titanium miniplates for fracture fixation at the mandibular angle

PURPOSE: The aim of this follow-up study was to evaluate the clinical usefulness of a new type of 3-dimensional (3D) miniplate for open reduction and monocortical fixation of mandibular angle fractures. PATIENTS AND METHODS: In 20 consecutive patients, noncomminuted mandibular angle fractures were treated with open reduction and fixation using a 2 mm 3D miniplate system in a transoral approach. All patients were systematically monitored until 6 months postoperatively. Among the outcome parameters recorded were infection, hardware failure, wound dehiscence, and sensory disturbance of the inferior alveolar nerve. RESULTS: The mean operation time from incision to wound closure was 65 minutes. Two patients had a mucosal wound dehiscence with no consequences. None developed an infection requiring a plate removal. All but 2 patients had normal sensory function 3 months after surgery. Plate fracture occurred in one patient in whom a preceding surgical removal of the third molar had been the reason for the mandibular fracture. In the absence of clinical symptoms, the patient declined plate removal. On final follow-up, fracture healing was considered clinically complete in all patients. CONCLUSIONS: The 3D plating system described here is suitable for fixation of simple mandibular angle fractures and is an easy-to-use alternative to conventional miniplates. The system may be contraindicated in patients in whom insufficient interfragmentary bone contact causes minor stability of the fracture.

Salivary antibodies directed against outer membrane proteins of Moraxella catarrhalis in healthy adults

Moraxella catarrhalis is a major mucosal pathogen of the human respiratory tract, but the mucosal immune response directed against surface components of this organism has not been characterized in detail. The aim of this study was to investigate the salivary immunoglobulin A (IgA) response toward outer membrane proteins (OMP) of M. catarrhalis in healthy adults, the group of individuals least likely to be colonized and thus most likely to display mucosal immunity. Unstimulated saliva samples collected from 14 healthy adult volunteers were subjected to IgA immunoblot analysis with OMP preparations of M. catarrhalis strain O35E. Immunoblot analysis revealed a consistent pattern of IgA reactivity, with the appearance of five major bands located at >250, 200, 120, 80, and 60 kDa. Eleven (79%) of 14 saliva samples elicited reactivity to all five bands. Immunoblot analysis with a set of isogenic knockout mutants lacking the expression of individual OMP was used to determine the identities of OMP giving rise to IgA bands. Human saliva was shown consistently to exhibit IgA-binding activity for oligomeric UspA2 (>250 kDa), hemagglutinin (200 kDa), monomeric UspA1 (120 kDa), transferrin-binding protein B (TbpB), monomeric UspA2, CopB, and presumably OMP CD. TbpB, oligomeric UspA2, and CopB formed a cluster of bands at about 80 kDa. These data indicate that the human salivary IgA response is directed consistently against a small number of major OMP, some of which are presently considered vaccine candidates. The functional properties of these mucosal antibodies remain to be elucidated.

"Death may come on like a stroke of lightening ..." : Phenomenological and morphological aspects of fatalities caused by manure gas

Due to the decomposition of biological material, hydrogen sulphide (H(2)S) is produced. In low concentrations, the well-known smell of "rotten eggs" is associated with H(2)S. In higher concentrations, H(2)S is an odourless and colourless gas that may cause rapid loss of consciousness, neurological and respiratory depression and imminent death-"... like a stroke of lightening". Hydrogen sulphide poisoning is an un-common incident that is often associated with colleague fatalities. In this study, 4 fatal accidents with 10 deceased victims are reported and the morphological and phenomenological aspects are presented. In these cases, the morphological findings, namely, discolouration of the livores, pulmonary pathologies and sub-mucosal or sub-serosal congestion bleeding were found in nearly all cases. Also the impending threat for colleagues, first aid helpers and professional rescue teams is demonstrated. The suspicion of a fatal H(2)S intoxication should be based on a precise scene analysis with respect to the possibility of life-threatening H(2)S intoxication for the helpers, the typical scent of rotten eggs, which may be noted on the corpses and the abovementioned morphological findings. The diagnosis should be confirmed by a qualitative and, if possible, quantitative analysis of H(2)S.

Intraocular microsporidiosis due to Encephalitozoon cuniculi in a patient with idiopathic CD4+ T-lymphocytopenia

Encephalitozoon cuniculi was documented to cause disseminated microsporidial infection including an iris tumor and endophthalmitis in an adolescent with idiopathic CD4+ T-lymphocytopenia. The diagnosis was established by microscopic, serologic and molecular methods. E. cuniculi (rabbit strain) was identified from the iris tumor, as well as from urine, conjunctival, corneal, and nasal swabs. Treatment with oral albendazole led to rapid improvement. This case raises the possibility of disseminated microsporidial infection in the context of idiopathic CD4+ T-lymphocytopenia and possibly advanced human immunodeficiency virus (HIV) infection, and above all the possibility of intraocular infection with E. cuniculi in humans.

Nationwide surveillance of nasopharyngeal Streptococcus pneumoniae isolates from children with respiratory infection, Switzerland, 1998-1999

The surveillance of pneumococcal antibiotic resistance and serotype distribution is hampered by the relatively low numbers of invasive pneumococcal infections. In Switzerland, a nationwide sentinel surveillance network was used to assess antibiotic resistance and serotype distribution among 1179 pneumococcal isolates cultured from 2769 nasopharyngeal swabs obtained from outpatients with acute otitis media or pneumonia during 1998 and 1999. The proportion of penicillin-susceptible pneumococcal isolates overall (87%) and among infants <2 years old (81%) was comparable to that of invasive isolates (90% and 81%, respectively). The high number of nasopharyngeal isolates allowed for the detection of a rapid increase in the number of penicillin-nonsusceptible pneumococcal (PNSP) strains in the West region of Switzerland, partly because of an epidemic caused by the 19F clone of Streptococcus pneumoniae. Clustering of risk factors for the carriage of PNSP isolates further explained the geographic variation in resistance rates. The nationwide sentinel surveillance of nasopharyngeal pneumococcus proved to be valuable for the monitoring of antibiotic resistance, risk factors for carriage of PNSP isolates, and serotype distribution and for the detection of the emergence of a new epidemic clone.

[HIV-associated thrombocytopenia]

Thrombocytopenia is a relatively frequent hematological complication of HIV (human immunodeficiency virus) infection. The incidence of thrombocytopenia in a cohort of 359 homo- or bisexual men with HIV infection was 3%, while it was 9% in a cohort of 321 HIV positive persons with a history of intravenous drug abuse. We followed 42 thrombocytopenic patients prospectively to study the clinical significance of thrombocytopenia in these patients. Thrombocytopenia was significantly more severe in intravenous drug abusers than in homo- or bisexual men: 52% of the drug abusers had thrombocyte counts below 10,000/mm3, compared with only 9% of the homo- or bisexual men. Symptoms of bleeding, almost always harmless skin or mucosal bleeding, were found in 45% of patients with a history of intravenous drug abuse and in 18% of the homo- or bisexual men. Life-threatening bleeding episodes did not occur during a median observation period of approximately one year. Prednisone was the most commonly used drug in symptomatic thrombocytopenia and had demonstrable effect only while being administered. After medication was stopped the thrombocyte counts usually fell to pretreatment values. Our findings suggest that therapy of HIV-associated thrombocytopenia should be reserved for severely symptomatic patients, particularly since this symptom of HIV infection rarely causes serious complications and we do not know the influence of drugs such as corticosteroids on the progression rate of HIV-infection.

Orthogonal polarization spectroscopy to detect mesenteric hypoperfusion

OBJECTIVE: Orthogonal polarization spectral (OPS) imaging is used to assess mucosal microcirculation. We tested sensitivity and variability of OPS in the assessment of mesenteric blood flow (Q (sma)) reduction. SETTING: University Animal Laboratory. INTERVENTIONS: In eight pigs, Q (sma) was reduced in steps of 15% from baseline; five animals served as controls. Jejunal mucosal microcirculatory blood flow was recorded with OPS and laser Doppler flowmetry at each step. OPS data from each period were collected and randomly ordered. Samples from each period were individually chosen by two blinded investigators and quantified [capillary density (number of vessels crossing predefined lines), number of perfused villi] after agreement on the methodology. MEASUREMENT AND RESULTS: Interobserver coefficient of variation (CV) for capillary density from samples representing the same flow condition was 0.34 (0.04-1.41) and intraobserver CV was 0.10 (0.02-0.61). Only one investigator observed a decrease in capillary density [to 62% (48-82%) of baseline values at 45% Q (sma) reduction; P = 0.011], but comparisons with controls never revealed significant differences. In contrast, reduction in perfused villi was detected by both investigators at 75% of mesenteric blood flow reduction. Laser Doppler flow revealed heterogeneous microcirculatory perfusion. CONCLUSIONS: Assessment of capillary density did not reveal differences between animals with and without Q (sma) reduction, and evaluation of perfused villi revealed blood flow reduction only when Q (sma) was very low. Potential explanations are blood flow redistribution and heterogeneity, and suboptimal contrast of OPS images. Despite agreement on the method of analysis, interobserver differences in the quantification of vessel density on gut mucosa using OPS are high.

Early implant placement with simultaneous guided bone regeneration following single-tooth extraction in the esthetic zone: a cross-sectional, retrospective study in 45 subjects with a 2- to 4-year follow-up

BACKGROUND: The concept of early implant placement is a treatment option in postextraction sites of single teeth in the anterior maxilla. Implant placement is performed after a soft tissue healing period of 4 to 8 weeks. Implant placement in a correct three-dimensional position is combined with a simultaneous guided bone regeneration procedure to rebuild esthetic facial hard and soft tissue contours. METHODS: In this retrospective, cross-sectional study, 45 patients with an implant-borne single crown in function for 2 to 4 years were recalled for examination. Clinical and radiologic parameters, routinely used in implant studies, were assessed. RESULTS: All 45 implants were clinically successful according to strict success criteria. The implants demonstrated ankylotic stability without signs of a peri-implant infection. The peri-implant soft tissues were clinically healthy as indicated by low mean plaque (0.42) and sulcus bleeding index (0.51) values. None of the implants revealed a mucosal recession on the facial aspect as confirmed by a clearly submucosal position of all implant shoulders. The mean distance from the mucosal margin to the implant shoulder was -1.93 mm on the facial aspect. The periapical radiographs showed stable peri-implant bone levels, with a mean distance between the implant shoulder and the first bone-implant contact of 2.18 mm. CONCLUSIONS: This retrospective study demonstrated successful treatment outcomes for all 45 implants examined. The mid-term follow-up of 2 to 4 years also showed that the risk for mucosal recession was low with this treatment concept. Prospective clinical studies are required to confirm these encouraging results.

[Oral erythroplakia and erythroleukoplakia: red and red-white dysplastic lesions of the oral mucosa--part 1: epidemiology, etiology, histopathology and differential diagnosis]

Oral erythroplakia (OE) and oral erythroleukoplakia (OEL; synonym: speckled leukoplakia) are working diagnoses for red and red-white lesions of the oral mucosa after exclusion of all other possible diagnoses for lesions with a similar clinical appearance. A good knowledge of oral medicine and possible differential diagnoses of oral mucosal pathologies is mandatory to correctly detect OE and OEL on this exclusion basis. In the present review article in a series of two, epidemiologic data, etiologic factors, possible differential diagnoses, and the histopathologic characteristics of OE and OEL will be presented and discussed regarding the current literature. A thorough histopathologic examination of these epithelial precursor lesions is mandatory to recognise the presence and the severity of epithelial dysplasia, which is a decisive factor for the subsequent treatment planning.

Soft tissue dehiscence coverage around endosseous implants: a prospective cohort study

AIM: To evaluate the healing outcome of soft tissue dehiscence coverage at implant sites. MATERIAL AND METHODS: Ten patients with one mucosal recession defect at an implant site and a contralateral unrestored clinical crown without recession were recruited. The soft tissue recessions were surgically covered using a coronally advanced flap in combination with a free connective tissue graft. Healing was studied at 1, 3 and 6 months post-operatively. RESULTS: Soft tissue dehiscences were covered with a coronal overcompensation of the flap margin up to 1.2 mm after the procedure. After 1 month, the coverage shrank to a mean of 75%, after 3 months to 70% and after 6 months to 66%. CONCLUSIONS: The implant sites revealed a substantial, clinically significant improvement following coronal mucosal displacement in combination with connective tissue grafting, but in none of the sites, a could complete implant soft tissue dehiscence coverage be achieved.

Influence of suture tension to the tearing characteristics of the soft tissues: an in vitro experiment

OBJECTIVES: To evaluate the influence of flap tension on the tearing characteristics of mucosal tissue samples in relation to various suture and needle characteristics. MATERIAL AND METHODS: Lining and masticatory mucosal tissue samples obtained from pig jaws were prepared for in vitro testing. Tension tearing diagrams of 60 experiments were traced for 3-0, 5-0 and 7-0 sutures with applied forces up to 20 N. In the second part, the same experiments were repeated with 100 diagrams to test the influence of needle characteristics with 5-0 and 6-0 sutures using only gingival tissue samples. RESULTS: 3-0 sutures mainly lead to tissue breakage at an average of 13.4 N. In contrast, 7-0 sutures only resulted in breakage of the thread at a mean applied force of 3.7 N. With 5-0 sutures, both events occurred at random at a mean force of 14.6 N. Irrespective of the needle characteristics, the mean breaking force for gingival samples with 5-0 and 6-0 sutures was approximately 10 N. CONCLUSIONS: Tissue trauma may be reduced by choosing finer suture diameters, because thinner (6-0, 7-0) sutures lead to thread breakage rather than tissue breakage.

Sirolimus and intraoperative hyperthermic peritoneal chemoperfusion with mitomycin-C do not impair healing of bowel anastomoses

Surgeons will increasingly have to address the development of gastrointestinal disease in transplant patients or deal with extended bowel resection and bowel anastomosis in advanced cancer patients. Immunosuppressants as well as intraoperative hyperthermic peritoneal chemoperfusion (IHPC) may alter intestinal anastomotic healing. We evaluated the effects of the immunosuppressant sirolimus and of IHPC on healing and stability of bowel anastomoses in pigs. Twenty-four pigs were divided into four groups (SIR: sirolimus was administered orally; IHPC: animals received IHPC with mitomycin-C; COMP: combination of sirolimus and IHPC was administered; CON: sham-treated control group). Animals underwent hand-sutured small bowel and left colon anastomoses and were killed on postoperative day 4. Anastomoses were evaluated by morphometric analysis and immunohistochemistry (IHC) and by measuring the bursting pressure (BP). In all experimental groups (SIR, IHPC, COMP), anastomotic BPs remained unaltered and were not statistically different compared with control (CON). In addition, ileum villous height and colonic crypt depth analysis revealed no significant difference in mucosal thickness, and IHC showed no difference among groups in proliferation, as assessed by the number of KI-67- and bromodeoxyuridine-labeled cells. Immunosuppression with sirolimus as well as IHPC with mitomycin-C do not alter healing of intestinal anastomosis in pigs.

Viral etiology of acute respiratory infections with cough in infancy: a community-based birth cohort study

BACKGROUND: Acute respiratory infections (ARI) are a major cause of morbidity in infancy worldwide, with cough and wheeze being alarming symptoms to parents. We aimed to analyze in detail the viral aetiology of ARI with such symptoms in otherwise healthy infants, including rhinoviruses and recently discovered viruses such as human metapneumovirus (HMPV), coronavirus NL63 and HKU1, and human bocavirus (HBoV). METHODS: We prospectively followed 197 unselected infants during their first year of life and assessed clinical symptoms by weekly standardized interviews. At the first ARI with cough or wheeze, we analyzed nasal swabs by sensitive individual real time polymerase chain reaction assays targeting 16 different respiratory viruses. RESULTS: All 112 infants who had an ARI had cough, and 39 (35%) had wheeze. One or more respiratory viruses were found in 88 of 112 (79%) cases. Fifteen (17%) dual and 3 (3%) triple infections were recorded. Rhino- (23% of all viruses) and coronaviruses (18%) were most common, followed by parainfluenza viruses (17%), respiratory syncytial virus (RSV) (16%), HMPV (13%), and HBoV (5%). Together rhinoviruses, coronaviruses, HMPV, and HBoV accounted for 60% (65 of 109) of viruses. Although symptom scores and need for general practitioner (GP) consultations were highest in infants infected with RSV, they were similar in infants infected with other viruses. Viral shedding at 3 weeks occurred in 20% of cases. CONCLUSIONS: Rhinoviruses, coronaviruses, HMPV, and HBoV are common pathogens associated with respiratory symptoms in otherwise healthy infants. They should be considered in the differential diagnosis of the aetiology of ARI in this age group.

Modulation of chemokine gene expression by Shiga-toxin producing Escherichia coli belonging to various origins and serotypes

Infection with Shiga-toxin producing Escherichia coli (STEC) may result in the development of the haemolytic-uremic syndrome (HUS), the main cause of acute renal failure in children. While O157:H7 STEC are associated with large outbreaks of HUS, it is difficult to predict whether a non-O157:H7 isolate can be pathogenic for humans. The mucosal innate immune response plays a central role in the pathogenesis of HUS; therefore, we compared the induction of IL-8 and CCL20 in human colon epithelial cells infected with strains belonging to different serotypes, isolated from cattle or from HUS patients. No correlation was observed between strain virulence and chemokine gene expression. Rather, the genetic background of the strains seems to determine the chemokine gene expression profile. Investigating the contribution of different bacterial factors in this process, we show that the type III secretion system of O157:H7 bacteria, but not the intimate adhesion, is required to stimulate the cells. In addition, H7, H10, and H21 flagellins are potent inducers of chemokine gene expression when synthesized in large amount.

Luminal starch substrate "brake" on maltase-glucoamylase activity is located within the glucoamylase subunit

The detailed mechanistic aspects for the final starch digestion process leading to effective alpha-glucogenesis by the 2 mucosal alpha-glucosidases, human sucrase-isomaltase complex (SI) and human maltase-glucoamylase (MGAM), are poorly understood. This is due to the structural complexity and vast variety of starches and their intermediate digestion products, the poorly understood enzyme-substrate interactions occurring during the digestive process, and the limited knowledge of the structure-function properties of SI and MGAM. Here we analyzed the basic catalytic properties of the N-terminal subunit of MGAM (ntMGAM) on the hydrolysis of glucan substrates and compared it with those of human native MGAM isolated by immunochemical methods. In relation to native MGAM, ntMGAM displayed slower activity against maltose to maltopentose (G5) series glucose oligomers, as well as maltodextrins and alpha-limit dextrins, and failed to show the strong substrate inhibitory "brake" effect caused by maltotriose, maltotetrose, and G5 on the native enzyme. In addition, the inhibitory constant for acarbose was 2 orders of magnitude higher for ntMGAM than for native MGAM, suggesting lower affinity and/or fewer binding configurations of the active site in the recombinant enzyme. The results strongly suggested that the C-terminal subunit of MGAM has a greater catalytic efficiency due to a higher affinity for glucan substrates and larger number of binding configurations to its active site. Our results show for the first time, to our knowledge, that the C-terminal subunit of MGAM is responsible for the MGAM peptide's "glucoamylase" activity and is the location of the substrate inhibitory brake. In contrast, the membrane-bound ntMGAM subunit contains the poorly inhibitable "maltase" activity of the internally duplicated enzyme.