Measurement of the refractive index of highly turbid media: reply to comment.

Peiponen et al. [Opt. Lett.35, 4108 (2010)] have expressed concern that a theoretical model we proposed in Calhoun et al. [Opt. Lett.35, 1224 (2010)] for total internal reflection from a turbid medium may be inconsistent with the experimental data, in the sense that the model fails to take into account unexplained oscillations in our data. We show that their concern arises from misinterpretation of our data and theory, and is, therefore, unfounded. NOTE: Optics Letters apologizes to the authors for the delay in the publication of this Reply.

Sensitive real-time measurement of the refractive index and attenuation coefficient of milk and milk-cream mixtures.

We demonstrate a first simultaneous measurement of both the refractive index and the attenuation coefficient (defined as the sum of the scattering and absorption coefficients) of highly turbid milk and milk-cream mixtures. We achieve this by observing the real-time reflectance profile of a divergent laser beam made incident on the surface of the milk sample. The experiments were carried out on commercial milk samples with fat volume concentrations of 0.5 or less, 1.6, and 3.3%, and on milk-cream mixtures with fat volume concentrations of 10 and 33.3%, without any dilutions of these samples. We find that the reflectance data are well described, for the first time without any empirical fit-parameters, by Fresnel theory that correctly includes the effect of angle-dependent penetration into the turbid medium on the total internally reflected signal. Therefore, our method provides the most accurate determination to date of the refractive index and attenuation coefficient of milk and milk-cream mixtures. Our sensor is compact, portable, and inexpensive.

Measurement of the refractive index of highly turbid media.

We demonstrate a first simultaneous measurement of the real and imaginary parts of the refractive index of a highly turbid medium by observing the real-time reflectance profile of a divergent laser beam made incident on the surface of the turbid medium. We find that the reflectance data are well described by Fresnel theory that correctly includes the effect on total internal reflection of angle-dependent penetration into the turbid medium.

The role of prostaglandins in liver ischemia-reperfusion injury.

Ischemia reperfusion (IR) of the liver is a multifactorial process that, at least in part, is responsible for the morbidity associated with major liver surgery under occlusion of the portal triad with the Pringle maneuver, total vascular exclusion or after liver transplantation. Surgeons are confronted with IR injury (IRI) more often than they anticipate. Although the human body has its own defense system, understanding the pathophysiology of IRI is essential for the surgeon in preventing and/or treating the reperfusion injury in common clinical practice. Several endogenous mechanisms exist to overcome IRI and a large number of pharmacological agents have also been found to confer protection against ischemic injury in the liver. They either blocked the injurious pathways directly or they subjected the liver to preconditioning. Prostaglandins (PGs) are a group of compounds derived from unsaturated 20-carbon fatty acids, primarily arachidonic acid, via the cyclooxygenase (COX) pathway. They are short-lived, hormone-like chemicals that regulate cellular activities on a moment-to-moment basis and are produced in most tissues of the body, although the liver has emerged as the major organ participating in the synthesis, degradation and elimination of arachidonate products of systemic origin. PGs are released through the prostaglandin transporter on the cell's plasma membrane. During the last decade intensive work on the cytoprotective effects of PGs on livers suffering from IRI have been well documented. Prostaglandins confer their protective effects on IR-injured livers mainly by inhibiting the generation of reactive oxygen species, preventing leukocyte migration, reducing the synthesis or production of membrane degradation products, improving hepatic insulin and lipid metabolism, and regulating the production of inflammatory cytokines and cell adhesion molecules. Production of PGs have been found essential also soon after partial hepatectomy for hepatocyte proliferation.

[Congenital and acquired esophagobronchial fistula].

We report a case of a patient with repeated intractable pneumonia due to congenital and acquired esophagobronchial fistula that was relieved by surgery. The patient was a 69-year-old female, who had repeatedly developed pneumonic symptoms since December 2000. It was found that she had a fistula from an esophageal diverticulum into the right bronchus and was diagnosed with congenital esophagobronchial fistula (Braimbridge classification type I). The patient was not relieved with conservative treatment and the diverticulum and fistula were subsequently excised. Considering the complications, lobectomy was not performed. In postoperative esophagraphy, a second fistula was found at a different site that was then removed during a second surgery. This fistula operation was formed a posteriori based on the conditions around the fistula. We had difficulty with the diagnosis and treatment. However, the patient had a good outcome With surgical treatment. A review of the relevant literature is also presented.

[Listeria monocytogenes meningitis complicated after operation for thoracic aortic aneurysm].

The patient was a 71-year-old male. He was admitted as an emergency to our hospital because of impending rupture of thoracic aortic aneurysm with anterior chest pain and hoarseness. The aneurysm was saccular type and located in the lesser curvature of aortic arch. Emergency operation was performed. Entry of the aneurysm was excluded by including artificial graft on the deep hypothermic circulatory arrest. Postoperative course was uneventful, but sudden depression of consciousness level and pyrexia were occurred 1 week after the operation. In spite of treatment, this patient was died 12 days after the operation. Autopsy revealed meningitis and pericarditis due to Listeria monocytogenes. Listeriosis is a zoonotic disease found in various kinds of animals. This bacteria is distributed naturally all over the world with a little frequency of Listeriosis. But, if the Listeriosis was appeared, mortality rate would be high. Appropriate recognition and treatment is mandatory.

Significance of fluorodeoxyglucose PET imaging in the diagnosis of malignancies in patients with biliary stricture.

AIM: This study was performed to evaluate the significance of positron emission tomography using fluorodeoxyglucose (FDG-PET) in diagnosing malignancy in patients with biliary stricture by comparing the sensitivity and specificity of FDG-PET with those of CT scans and cytological examination of the bile. METHODS: Thirty patients who underwent FDG-PET for differential diagnosis of the disease causing biliary stricture were included in this study. The sites of the strictures were as follows: in the intrahepatic bile duct in five patients, in the peripheral extrahepatic bile duct in 17 patients, and in the distal extrahepatic bile duct in eight patients. The sensitivity and specificity (%) of FDG-PET in diagnosing malignancies were evaluated and compared with those of CT scans and cytological examination using obtained bile. Final diagnoses were based on surgical or biopsy findings. Data was collected and analysed in a retrospective fashion. RESULTS: Malignant diseases were diagnosed in 21 patients, as follows: cholangiocarcinoma including Klatskin tumour in 10 patients, gallbladder cancer in eight, duodenal and ampulla cancer in two, and pancreatic cancer in one. In diagnosing malignancy in patients with biliary stricture, overall sensitivity and specificity were 85.7 (18/21) and 55.6 (5/9), respectively, for CT, 64.7 (11/17) and 100 (7/7), respectively, for cytological examination of the bile, and 90.5 (19/21) and 77.8 (7/9), respectively, for FDG-PET. CONCLUSIONS: In diagnosing malignant diseases in patients with biliary stricture, FDG-PET was superior to CT examination in both sensitivity and specificity, and superior to cytological examination of the bile in sensitivity. However, in patients with inflammatory disease, such as primary sclerosing cholangitis and cholecystitis, false positive rates were found. Therefore, a multidisciplinary diagnostic approach using FDG-PET in conjunction with conventional modalities seems essential to a precise differential diagnosis.

Analysis of prognostic factors after surgery for stage III and IV gallbladder cancer.

AIM: Survival and prognostic factors were analysed in patients who had undergone surgical resection with curative intention with the aim of identifying groups of patient with stage III and IV gallbladder cancer on the TNM classification who might benefit from surgery. METHODS: Thirty-seven patients with advanced gallbladder cancer were studied, the cumulative survival rate for each group was calculated for each pTNM factor. RESULTS: The 5-year survival rates in the stage III patients were 83.3%, while those for the stage IVA patients were 46.2%, and those for the stage IVB patients 16.7%. CONCLUSIONS: In patients with invasion of adjacent organs, including the liver and gastrointestinal tract, and rated as pT3 or pT4, extended surgery excising the invaded tissue may be justified. In patients with pN2 lymph-node metastasis, even without adjacent organ invasion, radical surgery may not achieve a good outcome.

Interleukin-10 suppresses proliferation and remodeling of extracellular matrix of cultured human skin fibroblasts.

When we previously examined the participation of local expression of interleukin-10 (IL-10) and tumor necrosis factor-alpha (TNFalpha) in wound healing of an intestinal anastomosis under septic conditions in mice, we found that IL-10 and TNFalpha expressions were markedly enhanced around the anastomosis and that wound healing was impaired in this animal model. The purpose of the present study was to investigate the combined effect of IL-10 on proliferation and remodeling of the extracellular matrix (ECM) of cultured human skin fibroblasts. Human skin fibroblasts were cultured for 48 h with IL-10 and/or TNFalpha at various concentrations, then the proliferation rates were determined using the MTT [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide] assay. The concentration of transforming growth factor-beta1 (TGFbeta1) in cell culture supernatants was measured by enzyme-linked immunosorbent assay, and type I collagen protein and matrix metalloproteinase-I (MMP-I) were detected by indirect immunofluorescence in cultured cells incubated for 48 h with 10 ng/ml of IL-10 and/or 10 ng/ml of TNFalpha. IL-10 itself had no effect on fibroblast proliferation, but reduced TNFalpha-induced fibroblast proliferation. The concentration of TGFbeta1 in cell culture supernatants was significantly lower in the presence of TNFalpha and IL-10 than in the presence of TNFalpha alone. Immunolabeling of fibroblasts for type I collagen protein was decreased in cells incubated with IL-10 and/or TNFalpha compared to controls. MMP-I immunolabeling was increased in cells incubated with IL-10, IL-10 and TNFalpha compared to control and cells incubated with TNFalpha. It is suggested that IL-10 is an inhibitory factor for the remodeling of the ECM during wound healing.

Use of multislice helical computed tomography cholangiography in the diagnosis of biliary disease.

A recent advance in computed tomography (CT) technology, multislice helical CT, has enabled production of clearer three-dimensional (3D) images and has drawn interest. We report the usefulness of CT cholangiography using a multislice helical CT scanner for the diagnosis and preoperative imaging of the biliary duct in a case of peculiarly shaped gallbladder with cholecystitis. A 34-year-old woman admitted to our hospital presented with chronic hypochondralgia. A CT scan showed that the gallbladder was normal without wall thickening or stones. However, there appeared to be a tumor, containing a stone approximately 1 cm in diameter, attached under the gallbladder in front of the right kidney and extending up to its lower level. Magnetic resonance cholangiography also depicted a normal gallbladder without wall thickening or stones. Hence, gallbladder stones were not diagnosed by previously the mentioned investigations. In contrast, a 3D image produced by multislice helical CT cholangiography was very clear. From the bottom of the gallbladder, a narrow canal continued to a stone. We diagnosed that the wall of the lower part of the long gallbladder had become thick and elongated because of chronic cholecystitis caused by a gallbladder stone, and laparoscopic cholecystectomy was performed. Macroscopically, the resected gallbladder showed an extremely thickened wall from the lower body to the fundus, in which a stone was located in the center. Multislice helical CT cholangiography has the potential to become one of the most significant examinations for diagnosis and anatomical analysis of biliary disease prior to laparoscopic cholecystectomy.

Is preoperative portal vein embolization effective in improving prognosis after major hepatic resection in patients with advanced-stage hepatocellular carcinoma?

BACKGROUND: The impact of the use of preoperative portal vein embolization (PVE) on long-term survival after surgery was evaluated by retrospective analysis of prognostic factors in patients with advanced-stage hepatocellular carcinoma (HCC) who had undergone hepatic resection with or without PVE. METHODS: The portal embolization group (Group P) consisted of 26 patients who had undergone major hepatectomy (more extensive than right hepatectomy) with PVE, and the nonembolized group (Group N) consisted of 43 patients who had undergone major hepatectomy without PVE. All patients were diagnosed with advanced HCC graded as Stage III or IV according to the International Union Against Cancer TNM classification system. Patient survival rates, recurrence rates, and recurrence sites after surgery in the two groups were evaluated and compared. RESULTS: The 1-year, 3-year, and 5-year cumulative disease specific survival rates in patients with TNM Stage III HCC, respectively, were 96.0%, 64.4%, and 52.7% in Group N and 92.9%, 57.1%, and 45.7% in Group P, whereas the corresponding values in patients with Stage IV HCC were 53.5%, 40.1%, and 26.8% in Group N and 63.5%, 50.8%, and 19.1% in Group P. There were no statistically significant differences in survival rates between Group P and Group N. Multivariate analysis showed that PVE was not a significant prognostic factor. The 1-year, 3-year, and 5-year cumulative recurrence rates for patients with both stages of disease combined were 44.1%, 80.2%, and 86.8% in Group N, respectively, and 39.9%, 72.2%, and 72.2% in Group P, respectively, with no statistically significant differences between the two groups. To date, 35 patients in Group N and 16 patients in Group P have had tumor recurrences in the liver remnant; of these, 27 patients in Group N and 12 patients in Group P had multiple recurrence foci in the liver remnant. No significant difference was seen between the two groups; however, 10 of 16 patients in Group P (62.5%) had remote organ metastasis in addition to recurrence in the liver remnant compared with only 6 of 35 patients in Group N (17.1%): This difference was significant statistically (P = 0.012). CONCLUSIONS: PVE during major hepatic resection neither improves nor worsens long-term prognosis but allows resection in a patient group that, otherwise, is considered as unresectable. Remote metastasis involving the lung, bone, or stomach was seen more frequently postoperatively in Group P compared with Group N, raising a possibly important issue regarding the use of this approach for the treatment of patients with hepatic malignancies, especially HCC.

Absence of mutations in the beta-catenin and adenomatous polyposis coli genes in papillary and follicular thyroid carcinomas.

beta-Catenin has multiple functions both in intercellular adhesion and in signal transduction. As a signaling molecule, mutations in exon 3 of the beta-catenin gene stabilize this protein in the cytoplasm. Subsequently, accumulated beta-catenin protein translocates to nuclei with T-cell factor-4, and upregulates transcriptional activity of the target genes involved in carcinogenesis. Mutations in exon 3 of the beta-catenin gene have been detected in various carcinomas. We examined immunolocalization of beta-catenin protein and mutations in the beta-catenin and adenomatous polyposis coli (APC) genes in papillary carcinoma (25 cases), follicular carcinoma (two cases), and benign thyroid tumor (29 cases). We detected no mutation in exon 3 of the beta-catenin gene in both malignant and benign thyroid tumors by polymerase chain reaction (PCR) and direct sequencing. No mutations in the mutation cluster region of APC were found in any tumor samples analyzed. Immunohistochemically, beta-catenin showed membranous localization in most specimens. These results suggest that mutations of the beta-catenin and APC genes are rare and that activation of the Wnt signaling pathway may not contribute to pathogenesis in human papillary and follicular thyroid carcinomas.

Retrohepatic vena cava replacement of hepatic malignancies without using total hepatic vascular exclusion or extracorporeal bypass.

Total hepatic vascular exclusion and venovenous bypass are frequently used surgical procedures when concomitant resection of the inferior vena cava is required during surgery of liver cancer involving the retrohepatic inferior vena cava close to the hepatic veins. However, the duration of total hepatic vascular exclusion is limited due to the risk of hepatic ischemia. Three patients presented with severely compressed inferior vena cava and/or hepatic veins due to liver cancer. The surgical procedure involved initial taping of the inferior vena cava just below the hepatic veins by extrahepatic division and taping of the hepatic veins. After taping the inferior vena cava, hepatectomy with caval resection was performed by simply clamping the retrohepatic inferior vena cava, without the need for total hepatic vascular exclusion or venovenous bypass. In all patients the retrohepatic inferior vena cava were safely replaced with a prosthetic graft under stable hemodynamics. Duration of the inferior vena cava clamping was 31, 66, 75 minutes, respectively. No graft-related complications occurred, but 2 of the 3 patients showed temporal renal dysfunction associated with renal congestion postoperatively. The surgical procedure described herein is effective for the treatment of retrohepatic inferior vena cava in some patients. However, when the case is complicated by chronic nephropathy or simultaneous nephrectomy is required, venovenous bypass should be performed.

Long-term survival after resection for small cell carcinoma of the esophagus.

We describe the rare case of a patient with esophageal small cell carcinoma who was completely cured. A 77-year-old man had small cell carcinoma of the esophagus with extensive lymph node metastases. Treatment comprised a subtotal esophagectomy and extended lymph node dissection. He has survived for more than 7 years with no evidence of recurrent disease. We suggest that radical operations should be considered for future patients if curative resection can be expected.

Surgical removal of left atrial myxoma through mini sternotomy and the superior transseptal approach.

A 32-year-old man admitted for treatment of a left atrial myxoma showed a 76 x 25 mm tumor in the left atrium originating in the interatrial septum upon echocardiography. The myxoma was surgically removed using a mini sternotomy and the superior transseptal approach. The hospital course was unremarkable. In the 2 years since operation, the patient has remained asymptomatic and tumor-free. The superior transseptal approach is thus useful in surgical removal of left atrial myxoma because it can be excised with minimum manipulation despite the mini sternotomy and small skin incision.

Protein expression of matrix metalloproteinases 2 and 9 and tissue inhibitors of metalloproteinase 1 and 2 in papillary thyroid carcinomas.

Matrix metalloproteinases (MMPs) and tissue inhibitors of metalloproteinases (TIMPs) play an important role in tumor invasion and metastasis. There have been only a few studies on the protein expression of MMPs and TIMPs in thyroid carcinomas. Therefore, we investigated the protein expression of MMP-2, MMP-9, TIMP-1 and TIMP-2 in 86 papillary thyroid carcinomas using immunohistochemistry, semiquantitative scoring morphometry of immunohistochemistry, gelatin zymography, and western blotting. We also examined the correlations between the immunohistochemical scores and several clinicopathological parameters. The immunoreactivities of MMP-2, MMP-9, TIMP-1, and TIMP-2 were largely located in the tumor cells or non-tumor follicular cells and to a much lesser extent in the fibroblasts and endothelial cells in the tumor and non-tumor regions. Compared with non-tumor regions, these four proteins tended to be overexpressed in the tumor cells; the overexpression was found in 64 of 86 (74%), 80 of 86 (93%), 79 of 86 (92%), and 64 of 86 (74%) cases for MMP-2, MMP-9, TIMP-1, and TIMP-2, respectively. Gelatin zymography showed distinct bands of MMP-2 and MMP-9 in tumor extracts but vague bands in non-tumor extracts. Western blotting revealed the specific bands of MMP-2 and MMP-9 in both tumor and non-tumor extracts. Morphometric scoring revealed that high expression of these proteins significantly correlated with large tumor size, presence of lymph node metastasis, high clinical stage, high intrathyroidal invasion, and high vascular invasion. These data suggest that MMP-2, MMP-9, TIMP-1, and TIMP-2 proteins and activities are increased in tumors cells of papillary thyroid carcinomas and that they play an important role in the invasion and metastasis of papillary thyroid carcinomas.

Effects of prosthetic valve placement on mitral annular dynamics and the left ventricular base.

Insertion of a rigid mitral prosthesis impairs the function of the mitral annulus and induces systolic narrowing of the left ventricular outflow tract (LVOT). To study this mechanism, we investigated dynamic changes in the left ventricular (LV) base, which consists of the mitral annulus and LVOT orifice. In seven patients with mechanical mitral valve prostheses and eight normal subjects, the image of the LV base was reconstructed three-dimensionally and its dynamic change during systole was studied. In the patients, the rigid prosthetic valve (=mitral annulus) tilted toward the left ventricle with a hinge point at the posterior mitral annulus during systole. The left ventricular base exhibited contraction, but the size of the prosthetic valve was constant. As a consequence, the prosthetic valve occupied more of the left ventricular base, which resulted in narrowing of the LVOT. In the normal subjects, the mitral annulus did not interfere with the region of the LVOT orifice during systole as the mitral annulus underwent both dorsiflexion and contraction. Thus, fixation of the mitral annulus induces an anti-physiologic motion of the annulus. Conscious preservation of annular flexibility in mitral valve surgery is important in avoiding potential dynamic LVOT obstruction.