Non-contact, two-dimensional measurement of tissue circulation in choroid and optic nerve head using laser speckle phenomenon

A new apparatus has been developed using the laser speckle phenomenon for non-contact, two-dimensional analysis of tissue circulation in the choroid and optic nerve head (ONH). The fundus was illuminated by a diode laser spot and its image speckle was detected by an image sensor. The difference between the average of the speckle intensity (Imean) and the speckle intensity for successive scannings was calculated, and the ratio of Imean to this difference was defined as normalized blur (NB), which is a quantitative index of blood velocity. The results were displayed on color graphic monitors showing the two-dimensional variation of the NB level in the measurement field. In the rabbit, this apparatus was used to study the relationship between the results of NB measurement and the choroidal blood flow determined by the microsphere technique, the relationship between NB obtained from the ONH tissue free of visible surface vessels and the ocular perfusion pressure (OPP) after a lethal injection of pentobarital, and the effect of intraocular pressure (IOP) on the NB in the choroid or in the ONH. A stepwise reduction in the OPP was introduced by elevating the IOP manometrically. The relative decrease in the average NB over the field measured, NBav, in the choroid with the reduction in OPP showed a significant correlation with the relative change in the blood flow rate determined using the microsphere technique (r = 0.60, P < 0.001). NBav in the ONH had a good correlation with the OPP after a lethal injection of pentobarbital (r = 0.98, P < 0.001). NBav in the choroid decreased with reduction in the OPP. Although NBav in the ONH was little affected by OPP change when OPP was above 40 mmHg, at OPP levels below 40 mmHg, NBav in the ONH decreased along with a reduction in the OPP. These results suggest that by using the present apparatus, the blood velocity in the choroid or ONH under various conditions can be studied non-invasively in the living eye.

Radical radiotherapy for medically inoperable non-small cell lung cancer in clinical stage I: a retrospective analysis of 149 patients

PURPOSE

In order to obtain the standard treatment results of medically inoperable non-small cell lung cancer (NSCLC) in Stage I in the post-CT scan era, a retrospective analysis of patients who were treated by radical radiotherapy was performed.

METHODS AND MATERIALS

149 cases treated between 1980 and 1989 were accumulated from ten large hospitals in Japan. All patients received a total dose of 55-75 Gy (mean 64.7 Gy) with conventional fractionation. For evaluation of treatment results, complete response (CR) rate, median survival period and long-termed survival rates were used.

RESULTS

The median survival of the all cases was 27.2 months and the actuarial 3- and 5-year survival rates were 34.2% and 22.2%, respectively. CR was obtained in 57 cases (38%). The CR rate was strongly correlated with the long-term survival (5-year survival rate in CR group: 35.1% compared with PR + NC group: 14.1% (P < 0.0001)). The size of tumor was also of prognostic importance. In 116 patients who died within 5 years after treatment, 66 patients (57%) died of local tumor regrowth.

CONCLUSION

Although the medically inoperable NSCLC patients in Stage I should be offered curative radiation therapy, development of some new steps to increase the CR rate and local control rate is urgently needed.

Involvement of up-regulation of 17beta-hydroxysteroid dehydrogenase type 1 in maintenance of intratumoral high estradiol levels in postmenopausal breast cancers

Estradiol (E2) and estrone (E1) levels as well as mRNA expression levels of aromatase, sulfatase and 17beta-hydroxysteroid dehydrogenase type 1 (17beta-HSD1) in breast cancer tissues were studied to elucidate the mechanism involved in the maintenance of the intratumoral high E2 levels in postmenopausal patients with very low serum E2 levels. Intratumoral E2 levels of postmenopausal patients (127.2 +/- 17.5 pg/g) (mean +/- SE) were not significantly different from those of premenopausal patients (110.1 +/- 10.1 pg/g) (p = 0.36). The mRNA expression levels of aromatase and sulfatase, determined by a quantitative real-time PCR, were not significantly different between premenopausal and postmenopausal breast cancers, but 17beta-HSD1 mRNA expression levels were significantly higher in postmenopausal than premenopausal breast cancers (p < 0.05). Intratumoral E2/E1 ratios were significantly higher in postmenopausal than premenopausal breast cancers (p < 0.01). These results demonstrate that the increased conversion from E1 to E2 catalyzed by 17beta-HSD1 may play an important role in the maintenance of the intratumoral high E2 levels in postmenopausal patients.

Mutation in the threonine synthase gene results in an over-accumulation of soluble methionine in Arabidopsis

In higher plants, O-phosphohomoserine (OPH) represents a branch point between the methionine (Met) and threonine (Thr) biosynthetic pathways. It is believed that the enzymes Thr synthase (TS) and cystathionine gamma-synthase (CGS) actively compete for the OPH substrate for Thr and Met biosynthesis, respectively. We have isolated a mutant of Arabidopsis, designated mto2-1, that over-accumulates soluble Met 22-fold and contains markedly reduced levels of soluble Thr in young rosettes. The mto2-1 mutant carries a single base pair mutation within the gene encoding TS, resulting in a leucine-204 to arginine change. Accumulation of TS mRNA and protein was normal in young rosettes of mto2-1, whereas functional complementation analysis of an Escherichia coli thrC mutation suggested that the ability of mto2-1 TS to synthesize Thr is impaired. We concluded that the mutation within the TS gene is responsible for the mto2-1 phenotype, resulting in decreased Thr biosynthesis and a channeling of OPH to Met biosynthesis in young rosettes. Analysis of the mto2-1 mutant suggested that, in vivo, the feedback regulation of CGS is not sufficient alone for the control of Met biosynthesis in young rosettes and is dependent on TS activity. In addition, developmental analysis of soluble Met and Thr concentrations indicated that the accumulation of these amino acids is regulated in a temporal and spatial manner.

Real-time measurement of human optic nerve head and choroid circulation, using the laser speckle phenomenon

A modification of a previously described instrument that used the laser speckle phenomenon for noncontact two-dimensional analysis of the fundus tissue circulation was devised so that tissue circulation in the optic nerve head (ONH) or choroid of the human eye could be measured on a real-time basis. The fundus was illuminated by a diode laser spot and the image speckle was recognized by an area sensor. A quantitative index of blood velocity, normalized blur (NB), was calculated by a logistic board every 0.125 seconds for 7 seconds. Using this modified device, the average NB of the measurement field in the temporal ONH, free of visible surface vessels (NBONH), and that in the posterior choroid (NBch) of normal human eyes were measured. The coefficients of reproducibility of 1-minute interval measurements were 11.7% for the NBONH) and 8.7% for the NBch (each, an average of 5 pulses), and those of 24-hour interval measurements were 13.0% (NBONH) and 9.7% (NBch). The pulsatile component average of NBONH was 38.4% of mean NBONH; of NBch, 26.6% of the mean NBch.

Atomic analysis and knoop hardness measurement of the cavity floor prepared by Er,Cr:YSGG laser irradiation in vitro

In the present study, the compositional changes and knoop hardness of the cavity floor prepared by Er,Cr:YSGG laser irradiation was compared with that of the conventional bur cavity. Fifteen laser and 15 bur cavities were cross-sectioned, and subjected to atomic analysis by SEM-EDX and knoop hardness test. Statistical analyses were performed using the Mann-Whitney U-test; a value of P < 0.01 was considered significant. Surface characteristics of the prepared cavities were also investigated by light microscopy and scanning electron microscopy (SEM). The results showed that the quantities of Ca (Ca weight %) and P (P weight %) were increased significantly in the laser cavity floor but no significant differences were found between the Ca/P ratio and knoop hardness number of laser and bur cavities. The SEM observation revealed that the lased cavity surface was irregular and there was also the absence of a smear layer; the orifice of dentinal tubules was exposed. Er,Cr:YSGG laser device is considered as one of the most effective and safe devices for cavity preparation because of its many advantages. This includes easy delivery system, minimal thermal damage to the surrounding tissues, minimal thermal-induced changes of dental hard tissue compositions, and favourable surface characteristic.

Image guidance of breast cancer surgery using 3-D ultrasound images and augmented reality visualization

This paper describes augmented reality visualization for the guidance of breast-conservative cancer surgery using ultrasonic images acquired in the operating room just before surgical resection. By combining an optical three-dimensional (3-D) position sensor, the position and orientation of each ultrasonic cross section are precisely measured to reconstruct geometrically accurate 3-D tumor models from the acquired ultrasonic images. Similarly, the 3-D position and orientation of a video camera are obtained to integrate video and ultrasonic images in a geometrically accurate manner. Superimposing the 3-D tumor models onto live video images of the patient's breast enables the surgeon to perceive the exact 3-D position of the tumor, including irregular cancer invasions which cannot be perceived by touch, as if it were visible through the breast skin. Using the resultant visualization, the surgeon can determine the region for surgical resection in a more objective and accurate manner, thereby minimizing the risk of a relapse and maximizing breast conservation. The system was shown to be effective in experiments using phantom and clinical data.

p21(Waf1/Cip1) and p53 protein expression in breast cancer

p21/Cip1/Waf1 (wild-type p53 activated fragment 1/cyclin-dependent kinase [Cdk]-interacting protein 1) is a prominent Cdk inhibitor and has been shown to be a downstream mediator of p53. In this study, we sought to clarify the clinical significance of Waf1 and the relationship between Waf1 and p53 in breast cancer. For this purpose, the expressions of Waf1 and p53 were evaluated immunohistochemically in a series of 104 patients. Waf1 was expressed in 51 (49%) of 104 tumors tested, and p53 in 33 tumors (32%). Inverse expression of these two proteins was seen in 76 cases (73%); 47 were Waf1-positive and p53-negative, and 29 were Waf1-negative and p53-positive. A comparison with clinicopathologic parameters showed that Waf1 expression correlated with negative lymph nodes (P<.01), a low histologic grade (P<.0001), and positive estrogen receptor status (P<.01). Recurrence-free survival was lower for patients with Waf1-negative tumors than for those with Waf1-positive tumors (P<.0001). In multivariate analysis, Waf1 expression and low histologic grade (1 or 2) tumors had an independent prognostic significance for recurrence-free survival. These results suggest that Waf1 is induced mainly by a p53-dependent pathway and could be a reliable indicator of recurrence in breast cancer.

Choroidal circulation in diabetic patients

PURPOSE

To evaluate choroidal circulatory changes in diabetic patients with and without background diabetic retinopathy (BDR) by measuring the retrobulbar circulation with colour Doppler imaging (CDI).

METHODS

CDI was used to measure circulatory parameters of the PCA (posterior ciliary artery), CRA (central retinal artery), OA (ophthalmic artery) and the respective veins in 73 diabetic patients and 22 controls in a sitting posture. Among the diabetic patients, 38 patients were without diabetic retinopathy (NDR) and 35 had BDR. A non-parametric Kruskal-Wallis test with a Dunn correction was used for data analysis.

RESULTS

End-diastolic velocity (EDV) in the PCA was decreased (2.55+/-0.80 cm/s) and resistivity index (RI) in the PCA was increased (0.70+/-0.08) in BDR patients compared with the control patients' EDV (3.23+/-1.08 cm/s, p = 0.01) and RI (0.62+/-0.06, p = 0.0003). RI in the CRA was significantly higher in the BDR group (0.74+/-0.09) than in the control group (0.68+/-0.08, p = 0.006). RI in the OA was significantly higher in the BDR group (0.87+/-0.06) compared both with the NDR group (0.83+/-0.07) and with the control group (0.81+/-0.06; p = 0.007, p = 0.004). NDR patients had a significantly higher RI in the PCA (0.67+/-0.08) than control patients (0.62+/-0.06, p = 0.01, while the CRA RI (0.71+/-0.09) did not show significant differences from the control group (0.69+/-0.08, p = 0.32). Decreased EDV in the CRA was detected in NDR patients (2.16+/-0.76 cm/s) compared with the controls (2.72+/-0.92 cm/s, p = 0.007).

CONCLUSION

The results from this study suggest that not only the retinal but also the choroidal circulation is affected in NDR and BDR patients.

Saccadic eye movements evoked by microstimulation of the fastigial nucleus of macaque monkeys

1. Systematic exploration throughout the deep cerebellar nuclei and white matter disclosed that the region from which saccadic eye movements (saccades) were evoked with weak currents (less than 10 microA) was confined to the fastigial nucleus and the adjacent white matter. 2. When an electrode for stimulation was advanced in the cerebellum, saccades were evoked in the direction of the stimulated side (ipsilateral saccades) as it entered the low-threshold region. In some tracks, particularly when the electrode was advanced in the medial portion of the fastigial nucleus, the direction of the evoked saccades changed from the ipsilateral to the contralateral. 3. The mappings with microstimulation disclosed that the ipsilateral saccades were elicited from a relatively wide region that included almost the full extent of the fastigial nucleus. The low-threshold region continued in the white matter caudally into vermal lobule VII and rostrally into the dorsal aspect of the brachium conjunctivum. On the other hand, the contralateral saccades were evoked from a relatively circumscribed region in the ventromedial portion of the fastigial nucleus. 4. The reversal in the direction of the horizontal component occurred always in a narrow zone in the core of the fastigial nucleus. The caudal part of this zone coincided with an ellipsoidal region where anterogradely labeled axons of the Purkinje cells terminated when HRP was injected into vermal lobule VII. 5. When bicuculline (0.2-1 microgram) was injected in the ellipsoidal region, the ipsilateral saccades evoked from the dorsocaudal aspect of the region were suppressed for several hours. On the other hand, the contralateral saccades evoked from the ventromedial portion of the fastigial nucleus were either unchanged or enhanced. 6. Because the ipsilateral saccades were suppressed by bicuculline, they were most probably evoked by stimulation of the presynaptic component of gamma-amino-butyric acid-(GABA) mediated synapses, namely the axons of Purkinje cells. 7. Because stimulation of the presynaptic component of the inhibitory synapses evoked ipsilateral saccades, activation of the postsynaptic component would evoke contralateral saccades. In fact, the distribution of the fastigial sites yielding contralateral saccades coincided with the course of axons of fastigial neurons arising in the ellipsoidal region. It is most likely, therefore, that the contralateral saccades were evoked by stimulation of fastigial neurons.(ABSTRACT TRUNCATED AT 400 WORDS)

A study on surface roughness and microleakage test in cavities prepared by Er:YAG laser irradiation and etched bur cavities

The purposes of this study were to investigate the surface morphology, suface roughness of cavities prepared by Er:YAG laser irradiation, and compared the microleakage degree after composite resin restoration with etched bur cavities, in vitro. In each of the 30 human extracted teeth, two shallow cavities were prepared; one prepared with the Er:YAG laser system on the buccal surface, and one produced on the lingual (palatal) surface with a high-speed turbine. Five cavities from each group were investigated by scanning electron microscopy (SEM), and five were subjected to surface roughness analysis by a colour laser three-dimensional (3D) microscope. The remaining cavities were filled with a composite resin and subjected to a microleakage test under thermocycling. Only bur cavities were acid-etched before filling. Statistical analysis was performed using the Mann-Whitney U test; a value of p <0.01 was considered significant. Morphologically, the prepared cavities showed an irregular surface with the absence of a debris-like smear layer; enamel prisms and opening of dentinal tubules were recognised. Surface roughness was significantly increased with the laser system. Microleakage test revealed no significant differences between the laser and bur cavities. Crosscut sections of the cavities with no microleakage showed no gap at the interface. Laser cavity may facilitate good adaptation of composite resin with enamel and dentine, because an increase of surface roughness and the openings of dentinal tubules may facilitate the formation of a hybrid zone, since a primer and an adhesive can penetrate the surface better when the smear layer is removed. It can be concluded that shallow cavity prepared by Er:YAG laser is capable of decreasing microleakage of composite resin restorations, and its efficiency is similar to etched bur cavities.

Prognostic significance of Ki67 index after neoadjuvant chemotherapy in breast cancer

PURPOSE

Recently, Ki67 index (cell proliferation marker) has been attracting a considerable attention as a prognostic factor in breast cancer but the prognostic significance of Ki67 after neoadjuvant chemotherapy (NAC) has rarely been examined.

EXPERIMENTAL DESIGN

Primary breast cancer patients (n = 102) treated with NAC (sequential paclitaxel 12 cycles (q1w) and 5-FU/epirubicin/cyclophosphamide 4 cycles (q3w)) were recruited in the study. Ki67, estrogen receptor (ER) and progesterone receptor (PR) and breast cancer resistant protein (BCRP) and P-glycoprotein were determined by immunohistochemistry and HER2 was determined by FISH in tumor tissues obtained before and after NAC, and their association with patient prognosis (relapse-free survival) was examined.

RESULTS

Of the 102 patients, pCR was achieved in 30 (29.4%). In the 72 non-pCR patients, Ki67 index significantly (P < 0.001) decreased after NAC. Ki67 index after NAC, but not Ki67 index before NAC, was significantly associated with a patient prognosis (P = 0.022). Multivariate analysis has shown that Ki67 index after NAC is a marginally significant (P = 0.05) prognostic factor and that other biomarkers including ER, PR, BCRP, and P-glycoprotein before and after NAC are not significant.

CONCLUSIONS

Ki67 after NAC, but not before NAC, is prognostic in breast cancer patients, and might be clinically useful in the prognosis prediction of patients who do not achieve pCR after NAC. On the other hand, BCRP and P-glycoprotein before and after NAC are unlikely to be useful as prognostic factors in these patients.

Relation between retrobulbar circulation and progression of diabetic retinopathy

AIMS

To investigate retrobulbar circulatory parameters in type 2 diabetic patients with and without diabetic retinopathy (DR) progression.

METHODS

This was a prospective cohort study. One eye of 35 diabetic patients with background DR (BDR) were included in the study. Eyes without DR, with proliferative DR, photocoagulation, past surgical procedures, or other ophthalmic disease except BDR and cataract were excluded. The study was masked. Colour Doppler imaging (CDI) was used to measure the retrobulbar circulation at the beginning of the study and after a mean follow up interval of 21 months. Peak systolic velocity (PSV), end diastolic velocity (EDV), and resistivity index (RI) in the central retinal artery and vein and the posterior ciliary artery were measured.

RESULTS

18 patients who developed DR progression showed significantly increased central retinal vein PSV ( 5.6 (3.5-9.1) p = 0.003), EDV ( 3.4 (2.3-4.4) p = 0.04), and RI ( 0.43 (0.20-0.56) p = 0.02) at the final measurement compared to the initial measurement (PSV = 4.6 (3.2-7.0); EDV = 3.0 (2.3-3.7); RI = 0.40 (0.17-0.52)). Circulatory parameters in the central retinal artery and the posterior ciliary artery did not alter significantly after progression of DR. 17 patients were without DR progression and they did not show any significant differences in the measured circulatory parameters on entry compared to the final measurement.

CONCLUSION

The authors suggest that the initial changes in the retrobulbar circulation during DR progression occur in the central retinal vein.

Effects of air constituents on thermosensitivities of preoptic neurons: hypoxia versus hypercapnia

The effects of hypoxia (10% O2) on the thermosensitivities of preoptic neurons were studied in urethanized rats and compared to the effects of hypercapnia (10% CO2). This was examined by regression of neuronal activity on preoptic temperature. During hypoxia, the slope of the regression line increased significantly in 8 (23%) of 35 warm-sensitive neurons and decreased in eight other neurons (P less than 0.05). During hypercapnia, the slope of the regression line decreased significantly in 7 (30%) of the 23 warm-sensitive neurons (P less than 0.05). No neuron was found that significantly increased the slope of the regression line. The effects of hypoxia on thermosensitivities (i.e. the slope of the regression line) of PO neurons differed from those of hypercapnia in chi-square analysis (P less than 0.05). Responses of the cold-sensitive neurons to hypoxia or hypercapnia did not generally differ from those of the warm-sensitive neurons. During hypoxia and hypercapnia, arterial blood pressure, respiratory frequency, heart rate, and EEG were recorded to examine their relations to neuronal activity. The present results indicate that the thermosensitivities of preoptic neurons are modified by both hypoxia and hypercapnia, but that hypoxic differ from hypercapnic effects.

Decreased expression of BRCA2 mRNA predicts favorable response to docetaxel in breast cancer

The clinical usefulness of BRCA1 and BRCA2 mRNA levels in tumor tissues in the prediction of response to docetaxel (DOC) treatment has been studied in breast-cancer patients. Twenty-five patients with locally advanced breast tumors (n = 13) or locally recurrent tumors (n = 12) underwent tumor biopsy and were treated with DOC (60 mg/m2 every 3 weeks). BRCA1 and BRCA2 mRNA levels in the tumors were determined by real-time PCR, and the expression of 6 biological markers (P-glycoprotein, p53, erbB2, BCL2, MIB1, estrogen receptor-alpha) in the tumors was determined by immunohistochemistry. BRCA2 mRNA levels (0.547 +/- 0.200, mean +/- SE) of responders to DOC treatment were significantly (p < 0.05) lower than those of non-responders (1.538 +/- 0.358), but there was no significant difference in BRCA1 mRNA levels between responders (0.389 +/- 0.081) and non-responders (0.779 +/- 0.172). Tumors were dichotomized into groups with high or low BRCA2 mRNA levels according to the cut-off value of 0.13. The response rate (25%) of tumors with high BRCA2 mRNA levels was significantly (p < 0.01) lower than that (100%) of tumors with low BRCA2 mRNA levels. Positive predictive value, negative predictive value and diagnostic accuracy of the BRCA2 mRNA assay in the prediction of response to DOC were 100%, 75% and 80%, respectively. No significant difference was found between responders and non-responders in the expression status of any of the other 6 biological markers. These results suggest that BRCA2 mRNA levels in tumor tissues might be clinically useful in the prediction of response to DOC treatment in breast-cancer patients.

Effects of scleral buckling and encircling procedures on human optic nerve head and retinochoroidal circulation

AIMS

To study the effects of segmental scleral buckling and encircling procedures on tissue circulation in the human optic nerve head (ONH) and choroid and retina.

METHODS

Using the laser speckle method, the normalised blur (NB) value, a quantitative index of tissue blood velocity, was measured every 0.125 seconds and averaged over three pulses in the optic nerve head (NB(ONH)) and choroid and retina (NB(ch-ret)) in 10 patients with unilateral rhegmatogenous retinal detachment (mean age 52 (SD 17)). NB(ONH), NB(ch-ret), and intraocular pressure (IOP) in both eyes, and blood pressure (BP) were measured before, and 1, 4, and 12 weeks after the scleral buckling and encircling procedure.

RESULTS

NB(ch-ret) on the buckled side was significantly reduced after surgery and smaller than that in the unoperated contralateral eye throughout the study period (ANOVA, p<0.0001). NB(ch-ret) on the unbuckled side, in the foveal area, NB(ONH), IOP, and BP showed no significant change.

CONCLUSIONS

It was indicated that the segmental scleral buckling procedure with encircling elements decreased tissue blood velocity in the choroid and retina on the buckled side but caused no significant change on tissue circulation in other areas of the fundus or ONH.

Topical latanoprost and optic nerve head and retinal circulation in humans

The purpose of the present study was to study the effect of a single instillation of latanoprost on the human optic nerve head (ONH) and retinal circulation. Using laser-speckle tissue blood flow analysis, normalized blur (NB; a quantitative index of tissue blood velocity) was measured every 0.125 sec at a temporal ONH site free of visible surface vessels. Measurements were averaged for 3 cardiac cycles (NB(ONH)). Color Doppler Imaging (CDI) was also used to evaluate peak systolic blood velocity (PSV), endo-diastolic velocity (EDV), and resistive index (RI) in the central retinal artery (CRA) and mean blood velocity (MV) in the central retinal vein (CRV). One drop of 0.005% latanoprost was instilled into one eye and its vehicle into the other in eleven healthy volunteers in a double-blinded manner. Measurements of bilateral NB(ONH), CDI parameters, intraocular pressure (IOP), blood pressure (BP), and pulse rate (PR) were performed before, and 45, 90, 180, and 270 min after instillation. After a single instillation of latanoprost or the vehicle, there was no significant bilateral difference throughout the experimental period. The difference in NB(ONH) between that before and at each time point of measurement (delta NB(ONH)) in the latanoprost-treated eyes was significantly higher between 45 and 270 min after instillation than that in vehicle-treated eyes (P = 0.0003 to 0.0156); ANOVA for repeated measurements also revealed significant difference between both eyes (P < 0.00001). BP, PR, and NB(ONH) in the eye that received only the vehicle, PSV, EDV, and RI in the CRA in both eyes, and MV in the CRV in both eyes changed little. Tissue blood velocity in the ONH increased at least temporarily following a single instillation of topical latanoprost. Although the mechanism of the increase is unclear, the effects of latanoprost on ONH tissue circulation in humans may have clinical implications.

Association of GSTP1 expression with resistance to docetaxel and paclitaxel in human breast cancers

AIMS

It has been reported that glutathione S-transferase P1 (GSTP1) expression is implicated in resistance to taxanes (docetaxel and paclitaxel) in human breast cancer cells in vitro. In the study presented here, we examine whether GSTP1 expression is associated with resistance to docetaxel or paclitaxel in human breast cancers. We also investigated the relationship between GSTP1 methylation status and response to these taxanes.

MATERIAL AND METHODS

Sixty two primary breast cancer patients were treated with docetaxel or paclitaxel as primary systemic treatment (PST). GSTP1 expression was detected immunohistochemically and the hypermethylation status GSTP1 gene was identified with a methylation specific primer assay.

RESULTS

The mean tumor reduction rate for all patients (n=62) was significantly (p<0.001) higher in GSTP1 negative (0.73+/-0.04; mean+/-standard error) than GSTP1 positive (0.31+/-0.09) tumors. The subset analysis showed that the mean reduction rate was significantly (p=0.005) higher in GSTP1 negative (0.59+/-0.06) than GSTP1 positive (0.11+/-0.13) tumors in the docetaxel group as well as in the paclitaxel group (p=0.006; GSTP1 negative tumors: 0.84+/-0.05; GSTP1 positive tumors: 0.56+/-0.08). On the other hand, GSTP1 methylation showed no significant association with the reduction rate.

CONCLUSION

Our present study has suggested that GSTP1 protein expression, but not GSTP1 methylation status, might be associated with response to docetaxel and paclitaxel. This suggests that GSTP1 immunohistochemical expression might be a potentially clinically useful predictive factor for response to docetaxel and paclitaxel.

Molecular characteristics of poorly differentiated adenocarcinoma and signet-ring-cell carcinoma of colorectum

In a series of 45 poorly differentiated adenocarcinomas (por) and 7 signet-ring-cell carcinomas (sig) of the colorectum, K-ras gene mutation, p53 immunostaining and microsatellite instability (MSI) were analyzed for a comparison with 46 cases of colorectal carcinomas of the well or moderately differentiated type (well/mod). In addition, the mutations of simple repeated sequences in the transforming-growth-factor-beta type-II receptor (T beta R-II) gene and the BAX gene were analyzed as possible targets for DNA replication errors. Mutation of the K-ras gene in the por, sig and well/mod specimens was detected in, respectively, 22%, 11% and 48%, positive immunostaining for p53 in 41.8%, 28.6% and 60.3%, and MSI in 36%, 30% and 4%. Frameshift mutation of the T beta R-II gene was detected in 27.5% of the por and none of the sig specimens, while corresponding figures for mutation of the BAX gene were 15.7% and 0%. Significant differences between the por and well/mod tumors were found in the occurrence of K-ras mutation at codons 12 and 13, and MSI. Clinicopathologically, the tumor status of por with MSI was found to significantly correlate with the tumor's location in the proximal colon. In cases without MSI and sig, no frameshift mutation of either the T beta R-II or the BAX gene was found. These results suggest that poorly differentiated and signet-ring-cell carcinomas have a genetic background different from that of well or moderately differentiated carcinomas of the colorectum, and that DNA-replication error is at least partly involved in the carcinogenesis of these specific types of colorectal carcinomas.

Retrobulbar circulation in myopic patients with or without myopic choroidal neovascularisation

AIM

To investigate the effect of myopia and myopic choroidal neovascularisation (CNV) on retrobulbar circulation in central retinal artery (CRA) and vein (CRV) and posterior ciliary artery (PCA).

METHODS

52 subjects with and without myopia were included in the study. Retrobulbar circulation was measured using colour Doppler imaging. Analysis of correlation of degree of myopia with blood flow velocity parameters was done. Circulatory differences between eyes of patients with unilateral neovascular degenerative myopia were estimated.

RESULTS

The analysis of correlation between dioptry and blood flow velocity in the CRA, CRV, and PCA showed a significant positive correlation. Axial length was also significantly correlated with CRA and CRV blood velocity and had a tendency to be correlated with PCA blood velocity. When compared with the fellow eye, the eye with myopic CNV had significantly higher resistivity index (RI) (p=0.048) in the PCA and no significant difference in the circulatory parameters of the CRA and CRV.

CONCLUSION

Central retinal and posterior ciliary blood velocity decreases with the increase of the degree of myopia. PCA RI is higher in myopic CNV.

Mammaglobin B as a novel marker for detection of breast cancer micrometastases in axillary lymph nodes by reverse transcription-polymerase chain reaction

A novel reverse transcription-polymerase chain reaction (RT-PCR) assay using mammaglobin B gene was developed for detection of breast cancer micrometastases in axillary lymph nodes. Fourteen primary breast cancers and 56 axillary lymph nodes from six patients with primary breast cancer and 15 control lymph nodes from non-cancer bearing patients were subjected to this assay. The transcript of mammaglobin B gene was detected in none of the control lymph nodes, but in all of the 14 primary breast cancers. Eleven out of the 56 lymph nodes from the patients, which were shown to be positive by histological examination, were also proven positive by this assay. On the other hand, fourteen of the 45 (31%) histologically negative lymph nodes were also shown to express mammaglobin B mRNA, which suggested the presence of micrometastases in these lymph nodes. RT-PCR using mammaglobin B gene could therefore be a useful tool for detection of micrometastases of breast cancer.

Transareolar endoscopy-assisted partial mastectomy: a preliminary report of six cases

Six patients with breast cancer in the upper inner quadrant underwent endoscopy-assisted partial mastectomy. The tumor was removed with a 2-cm-wide surgical margin through a periareolar semicircular incision using a special retractor and endoscope system for plastic surgery. Another small incision was made in the axilla for total lymph node dissection or sentinel lymph node biopsy. The average of total operation time in five patients who underwent partial mastectomy was 241 minutes (range, 190-315 minutes), and the average time for the procedure of partial mastectomy in six cases was 84 minutes (range, 69-113 minutes). The cosmetic outcome was excellent. Transareolar endoscopic partial mastectomy can be considered as an alternative surgery option and can offer great cosmetic advantage for patients with small cancers in the inner quadrants of the breast.

Expression of tumor suppressor gene p16(INK4) products in primary gastric cancer

Recent studies have shown that the cyclin-dependent kinase (CDK) inhibitor p27(Kip1) represents an indicator for patients' outcome in several human malignancies including gastric cancer. However, the clinicopathologic value of another class of CDK inhibitor, p16(INK4), has not been determined. In a retrospective study, we examined the expression of p16(INK4) by immunohistochemical assay of 80 samples of primary gastric cancers and their adjacent nonneoplastic mucosas. Less than 10% of non-tumor gastric mucosal cells were p16(INK4) positive, whereas the expression of p16(INK4) in gastric cancer cells varied widely from 0 to 100% (mean, 24.5%). The expression of p16(INK4) was not seen in 11.3% (9/80) of the cancer cases, but in 65% (52/80) this protein was even overexpressed when compared with the nonneoplastic mucosa. A clinicopathologic survey indicated that a low or no expression of p16(INK4) was associated with poorly differentiated carcinoma (p = 0.0133), but the level of expression did not correlate with other parameters including patients' prognosis or with the expression of the pRb protein. In an effort to explore the underlying mechanism for the p16(INK4)-negative cases, a prospective study was also performed on 20 cases of gastric cancer to compare the level of the p16(INK4) protein with the methylation status of the p16(INK4) promoter. Gastric cancer tissues with methylation expressed significantly lower levels of the p16(INK4) protein (p = 0.0013) and two of them lacked p16(INK4) expression altogether, whereas all the cancer tissues without methylation expressed it. These findings suggest that the p16(INK4) protein may be associated with differentiation of gastric cancer tissues and that methylation of the p16(INK4) promoter may, in part, account for the loss of p16(INK4) expression.