Natural, polarized light and the choice of composite: a key to success in shade matching of direct anterior restorations- Part I.

The biggest challenge while restoring anterior teeth is shade matching. Hue, chroma, value, opacity, translucency, intensity and anatomy must be seen to be reproduced. To see we need light, knowing that there is a strong relation between the nature of light and the components of natural teeth. This article enlightens the way to do the shade matching and the stratification of anterior teeth by choosing the relevant materials to mimic the nature. The physical properties of natural and polarized light will be studied to understand their correlation with dental materials and natural teeth to use them in the best combination.

Natural, polarized light and the choice of composite: a key to success in shade matching of direct anterior restorations- Part II.

With time, natural and polarized light proved their importance and utility in dental photography. After studying the physical properties of natural and polarized light, in the first part of this article, to understand their correlation with dental materials and natural teeth and how to use them in the best combination, this second part will illustrate the importance of a polarized image in color matching, how to manipulate it and how to apply it in clinical cases.

Stratification in anterior teeth using one dentine shade and a predefined thickness of enamel: a new concept in composite layering--Part I.

Restoring an anterior tooth has always been a challenge, regarding the shade matching, the choice of colors, opacities, translucencies of our composites and the final anatomical outcome. This article proposes a new method for color matching and a clinical stratification using a simple and reproducible procedure for anterior restorations. The physical and optical characteristics of enamel and dentine will be studied and applied to our dental materials that we are using to restore anterior teeth.

Stratification in anterior teeth using one dentine shade and a predefined thickness of enamel: a new concept in composite layering--Part II.

While restoring an anterior tooth, shade matching is one of the crucial points that we can face to have an esthetic final outcome. After studying the physical and optical characteristics of enamel and dentine in the first part of this article, the second part will propose a new method for color matching and a clinical stratification using a simple and reproducible procedure for anterior restorations with only one dentine and one enamel shade.

DG-RAR for the treatment of symptomatic grade III and grade IV haemorrhoids: a 12-month multi-centre, prospective observational study.

BACKGROUND: Ultrasound-guided techniques represent a new treatment option in the treatment of haemorrhoids. Doppler-guided haemorrhoidal artery ligation (DG-HAL) proved efficacious in early haemorrhoidal disease, but lacks efficacy for stages III/IV. For these patients, haemorrhoidal artery ligation (HAL) has been combined with a running suture to reduce prolapsing haemorrhoidal tissue (recto-anal repair (RAR)). METHODS: A prospective observational study was conducted in 184 patients with grade III (58 %) or grade IV (42 %) haemorrhoids in seven coloproctological centres. Primary endpoints were the recurrence of symptoms and need of further treatment (medical or surgical). RESULTS: Post-operative complications were seen in 8 % of patients. After a follow-up of 3 months, 91 % of patients were free of symptoms and 91 % of patients were satisfied with the result. After a follow-up of 12 months, 89 % of patients were free of symptoms and 88 % were satisfied with the result. Nineteen per cent of patients received further medical or surgical treatment. CONCLUSIONS: Doppler-guided recto-anal repair (DG-RAR) proves to be an effective treatment option for the treatment of advanced haemorrhoidal disease that shows equal results to other established treatment options.

Rapid progression of an anal Buschke-Lowenstein tumour into a metastasising squamous cell carcinoma in an HIV-infected patient.

BACKGROUND: Buschke-Löwenstein tumour (BLT) of the anogenitalia is a locally invasive, destructively growing verrucous carcinoma that does not metastasise. Histologically BLT resembles benign condylomata acuminata. Nevertheless, the tumour grows relentlessly and may rarely progress into squamous cell cancer (SCC). RESULTS: A human immunodeficiency virus (HIV)-infected immunosuppressed patient developed (peri)anal warts accompanied by recurrent abscesses and fistulae. Histology revealed condylomata acuminata, and low-risk genital human papillomavirus (HPV) type 11b was detected. Six months later, the tumour had progressed into an ulcerated SCC that destroyed the rectum and perineum, with metastases to the inguinal lymph nodes. Whereas highly active antiretroviral therapy (HAART) effectively suppressed HIV replication, radiochemotherapy plus anti-EGFR antibody did not halt tumour progression, and the patient died from tumour-cachexia. DISCUSSION: As far as is known, this is the first report demonstrating rapid progression of a BLT into a metastasising SCC in an HIV-infected patient.

Preemptive analgesia by lornoxicam--an NSAID--significantly inhibits perioperative platelet aggregation.

BACKGROUND AND OBJECTIVE: To investigate whether preemptive administered lornoxicam changes perioperative platelet function during thoracic surgery. METHODS: A total of 20 patients scheduled for elective thoracic surgery were randomly assigned to receive either lornoxicam (16 mg, i.v.; n = 10) or placebo (n = 10) preoperatively. All patients underwent treatment of solitary lung metastasis and denied any antiplatelet medication within the past 2 weeks. Blood samples were drawn via an arterial catheter directly into silicone-coated Vacutainer tubes containing 0.5 mL of 0.129 M buffered sodium citrate 3.8% before, 15 min, 4 h and 8 h after the study medication was administered. Platelet aggregation curves were obtained by whole blood electrical impedance aggregometry (Chrono Log). RESULTS: Platelet aggregation was significantly reduced 15 min, 4 h and 8 h after lornoxicam administration compared to placebo (P < 0.05) for collagen, adenosine diphosphate and arachidonic acid as trigger substances. Adenosine diphosphate-induced platelet aggregation decreased by 85% 15 min after lornoxicam administration, and remained impaired for 8 h. CONCLUSION: Platelet aggregation assays are impaired for at least 8 h after lornoxicam application. Therefore perioperative analgesia by use of lornoxicam should be carefully administered under consideration of subsequent platelet dysfunction.

Human papillomavirus type 26 infection causing multiple invasive squamous cell carcinomas of the fingernails in an AIDS patient under highly active antiretroviral therapy.

Squamous cell carcinoma (SCC) of the nail unit is a rare disorder. An association with high-risk genital human papillomavirus (HPV) infection has been reported. We report a 28-year-old human immunodeficiency virus (HIV)-infected bisexual man who had multiple invasive SCC of the fingers, infected with the rare type HPV 26. Classification of HPV 26 as high- or intermediate-risk type has been uncertain, due to its rare presence in cervical cancer. Despite successful treatment with highly active antiretroviral therapy (HAART), the patient developed extensive hyperkeratotic nailbed proliferations of all fingers. Tumours were refractory to treatment and invaded into adjacent tissues. X-rays of the hands demonstrated bone invasion, necessitating amputation of distal phalanges of several fingers. Histologically, highly differentiated preinvasive and invasive verrucous SCCs were identified. Molecular DNA typing identified HPV 26 in the SCCs and in some premalignant lesions. By in situ hybridization HPV 26 DNA was detected in numerous tumour cells, indicating productive infection with high-level amplification of the viral genome. In the remaining proliferations, high-risk HPV type 58, cutaneous HPVs and a putative new HPV type were identified. HPV 26 infection appears to be causally involved in the development of SCC of the nail unit in this immunosuppressed patient. Timely evaluation of chronic verrucous nailbed tumours is recommended, especially in immunocompromised patients. Identification of HPV 26, besides known high-risk HPV types, may identify patients at risk for developing SCC of the nailbed and possibly at other locations.

Influence of hypotensive and normotensive anesthesia on platelet aggregability and hemostatic markers in orthognathic surgery.

This prospective randomized study investigated the influence of normotensive and hypotensive general anesthesia on platelet aggregability, intraoperative blood loss and parameters of plasmatic coagulation during extensive orthognathic surgery. A total of 30 patients were randomly allocated for either normotensive anesthesia maintained by continuous infusion of propofol and remifentanil (NORMO, n=10) or hypotensive anesthesia, whereby hypotension was induced by increasing the infusion rate of remifentanil (HYPO-R, n=10) or by administration of nitroglycerin (HYPO-N, n=10). Whole blood platelet aggregability was significantly reduced during hypotension compared to normotensive anesthesia (P<.01, HYPO-N and HYPO-R vs. NORMO). Mean arterial blood pressure during hypotension correlated well with adenosinediphosphate- (R=.712, P<.001) and collagen-induced platelet aggregability (R=.685, P<.001). Within hypotensive study groups, postoperative fibrinogen levels were significantly different, whereas intraoperative platelet aggregability, postoperative platelet count, prothrombin time, activated partial thromboplastin time and antithrombin levels were not different. Normotensive anesthesia, however, caused significant decreases in platelet count (-29%), prothrombin time (-24%), fibrinogen (-41%) and antithrombin (-28%) and a significant prolongation in activated partial thromboplastin time (+21%) and thrombin time (+18%). There was a trend to reduced intraoperative blood loss in hypotensive study groups; however, differences were not significant. In conclusion, induced hypotension--independent of substances used for induction of hypotension--reduces intraoperative platelet aggregability, subsequently protecting the coagulation system against subclinical consumption coagulopathy. Induced hypotension-caused platelet dysfunction does not lead to an increased intraoperative blood loss, but quite on the contrary shows a trend to reduced intraoperative blood loss, possibly by preventing platelet-induced subclinical consumption coagulopathy.

[Complete resection of isolated lung metastasis from breast carcinoma results in a strong increase in survival]. / La resezione completa delle metastasi polmonari isolate in seguito a carcinoma mammario prolunga significativamente la sopravvivenza.

BACKGROUND: Surgical treatment of pulmonary resection for metastatic disease has been proven a valuable therapeutic concept for a variety of neoplasms. Concerning breast cancer, at least 25% of patients develop distant metastases. In spite of increasingly sophisticated palliative therapies, the survival of these patients did not appear significantly prolonged during the last 25 years (19-32 months following diagnosis) and about 95% die from metastatic disease. METHODS: Between 1977 and 1997, three epidemiological comparable groups out of a total of 125 patients of our clinic were treated for isolated pulmonary metastasis following breast cancer. Complete data from 96 patients were retrospectively analyzed following stratification to three groups according their surgical therapy: C, complete resection, 28 patients; I, incomplete resection, 34 patients; N, no resection, 34 patients. RESULTS: Comparison of the three therapy methods concerning stage, histology and receptor levels of the primary tumor, number of metastases and the disease free interval (DFI), as well as adjuvant therapy modalities yielded no significant differences. Mean survival of group C was with 79 months (5-years-survival 80%, 10-years-survival 60%) significantly better compared to groups I and N (p < 0.00002). Mean survival of group I and N was not significantly different (15.5 and 9 months respectively). The DFI had no impact on the survival of group C, but showed a high correlation with the survival of group N (R2 = 0.81). CONCLUSIONS: Routine chest X-ray is necessary in the follow-up of breast cancer patients and if coin lesions occur, thoracic surgeon should be contacted.

Early detection of preeclampsia by determination of platelet aggregability.

Preeclampsia is still a leading cause of maternal and fetal morbidity and mortality. There is evidence for the involvement of platelets. Therefore, we investigated the suitability of corrected whole blood impedance aggregometry as an early predictor of preeclampsia in 71 consecutive, high-risk pregnancies. According to the occurrence of preeclampsia, defined postpartum by an independent investigator, and the stage of pregnancy (early and late, cutoff: 25 weeks of gestation), four study groups were defined. Platelet aggregation data were corrected for the influence of hematocrit and platelet count by a special purpose software package. Women developing preeclampsia showed significantly higher platelet aggregation response compared to controls in early and late pregnancy. In early pregnancy, all women developing preeclampsia had aggregation responses to collagen higher than the highest responses among the controls. Hence, this test had a 100% positive predictive value of subsequent preeclampsia. Despite being significantly increased, platelet aggregability was of minor predictive value in late pregnancy. We conclude that preeclampsia is accompanied by exaggerated platelet aggregability, particularly perceptible early in the course of pregnancy. We propose collagen-induced whole blood platelet aggregation with correction for the influence of hematocrit and platelet count for early detection of preeclampsia.

Changes of platelet surface antigens in patients suffering from abdominal septic shock.

Sepsis and related syndromes account for a high morbidity and mortality caused by the development of multiorgan failure. Pathogenesis of sepsis is complex, involving humoral as well as cellular factors. Since the role of platelets is still undefined in this concern, we investigated CD63, CD62P, CD36, and CD31 expression on platelets of patients in septic shock (n = 18) using a flow cytometric assay in whole blood. Samples were drawn within 24 hours of onset. We found thrombocytopenia accompanied by a significantly higher expression of CD63, CD62P, and CD31 and a significant downregulation of CD36 in comparison to healthy volunteers (n = 18). Changes in CD63 and CD62P expression indicates platelet activation. Because CD62P, CD36, and CD31 mediate interaction of platelets with leukocytes, subendothelial matrix and probably endothelial cells as well as platelet adhesion/aggregation, our findings suggest an involvement of platelets in leukocyte/endothelial cell interaction in septic shock. We suspect that thrombocytopenia is not due to bone marrow depression, but rather is due to consumption of highly activated platelets in the microcirculation. We feel that our observations may offer a rationale for potentially beneficial effects of antiplatelet therapy in sepsis; however, further studies have to evaluate its beneficial impact as well as its potential risk for bleeding complications.

Bcl-2 protein expression correlates with nodal status in non small cell lung cancer.

We investigated the immunohistochemical expression of bcl-2 in 55 non small cell lung cancer patients in order to understand if the altered expression of this gene is involved in the development of this kind of neoplasm. Our results showed bcl-2 immunopositivity to be a frequent event in non small cell lung cancer (54.5%) with a higher expression in squamous carcinomas compared to adenocarcinomas (p = .04). In addition, we found a positive correlation between bcl-2 expression levels and nodal status (p < .003). We suggest that bcl-2 immunostaining could be considered as marker of loco-regional invasivity.

[Significant extension of survival by complete resection of isolated lung metastases after breast carcinoma]. / Signifikante Verlängerung des Uberlebens durch komplette Resektion isolierter Lungenmetastasen nach Mammacarcinom.

At least 25% of breast cancer patients develop distant metastases. In spite of increasingly sophisticated palliative therapies, the survival time of patients with metastasis did not appear to be significantly prolonged during the last 25 years (19-32 months following diagnosis) and 95% of them die from metastatic disease. Therefore, it seems appropriate that the therapeutic risk/benefit ratio and impact on quality of life should be reassessed when asymptomatic patients are treated. Surgical treatment and pulmonary resection for metastatic disease has been proven a valuable therapeutic concept for a variety of malignancies. Three epidemiologically comparable collectives out of a total of 125 patients from our clinic were treated for isolated pulmonary metastasis following breast cancer (observation period: 1977-1997). Complete data sets could be established for 96 patients and were retrospectively analyzed following stratification into three groups according to their surgical therapy. Twenty-eight patients underwent complete resection (K), 34 had incomplete resections (I) and 34 had no surgical intervention for lung metastases (N). Comparison of the three therapy arms concerning stage, histology and receptor levels of the primary tumor, number of metastases, and the disease-free interval yielded no significant differences between groups K, I and N. Patients after complete resection of isolated lung metastases (group K) had a mean survival of 79 months (5-year survival 80%, 10-year survival 60%). This was significantly better than groups I and N (P < 0.00002). The mean survival of groups I and N was not significantly different (15.5 and 9 months respectively). The disease-free interval after operation of the primary tumor had no impact on the survival of group K, but showed a high correlation with the survival of group N (R2 = 0.81). Complete resection of isolated pulmonary metastases from carcinoma of the breast results in marked prolongation of survival with a low morbidity rate. Hence, routine chest X-ray should be considered an indispensable part of the oncological aftercare in breast cancer patients.

Variable platelet response to low-dose ASA and the risk of limb deterioration in patients submitted to peripheral arterial angioplasty.

A group of 100 patients with intermittent claudication (70 male, 30 female), treated with I00 mg ASA per day, were followed over 18 months after elective percutaneous balloon angioplasty. Platelet function was monitored over a period of 12 months by corrected whole blood aggregometry (CWBA). Upon stimulation by arachidonic acid (AA), adenosine diphosphate (ADP) and collagen, CWBA-results were obtained by an electronic acquisition and evaluation system correcting for hematocrit and platelet count of the blood sample. All patients showed a completely inhibited platelet response to AA stimulation. Comparison of the CWBA-results with clinical parameters revealed that reocclusions at the site of angioplasty occurred exclusively in male patients for which CWBA failed to prove an inhibition of aggregation upon both agonists, ADP and collagen, and for these patients the risk of complication is at least 87% higher (p = 0.0093). Only 40% of male patients show the expected effect of ASA on in vitro platelet aggregation at any given point in time and CWBA is capable of predicting those male patients which are at an elevated risk of reocclusion following peripheral angioplasty.

Racial variation in lung cancer.

Lung cancer claimed about 153,000 lives in 1994 in the United States. Despite research overall lung cancer survival has still not improved during the last 20 years, with 5-year relative survival remaining about 13%. In addition several epidemiologic and molecular studies showed a difference in the incidence of lung cancer in the three major races. The aim of our study was to investigate the variations of race in lung cancer patients, in order to identify potential risk factors linked to the different racial status. In this light we compared a 10 years lung cancer data of black population from Howard University Hospital, Washington D.C., U.S.A. and a 20 years data of white population from the Vienna University Hospital, Austria. Our results did not show any significant difference in mean age or tumor localization in both groups, but highlighted a remarkable difference in the incidence of the lung cancer histological types also according to the sex. In this respect it could be more successful to consider carcinogenesis like a protracted process of gene function deregulation in response to cell injury from exposure to genotoxic substances with individual specificity.

Ethnic variations in lung cancer.

Cancer of the lung is the most frequent cancer in the world, but with wide geographical variation in risk. It is most spread among males of all races worldwide, the only exception being its incidence among Chinese women aged 70 years and older. When comparing the different ethnic groups we have to consider that besides inhaling cigarette smoke actively or as a passive smoker the exposure to occupational carcinogens varies considerably according to different work places. In our study we compared 10 years of data from African-Americans in Howard University Hospital, Washington D.C. with 20 years of data from the white population in the University Hospital of Vienna, Austria. Ethnic patterns are generally consistent within each group in terms of both incidence and mortality. The difference in susceptibility between the sexes, the three major racial groups and already proven differences in genetic variations indicate the difference between individuals concerning the initiation and progression of lung cancer.