bluuebunny/crossref_metadata_2025 huggingface dataset:
A comparison of the clinical outcome between open and hand‐assisted laparoscopic nephroureterectomy for upper urinary tract transitional cell carcinoma
Authors: Hsueh Thomas Y. , Huang Yi‐Hsiu , Chiu Allen W. , Shen Kun‐Hung , Lee Ying‐Huei
Published: October 2004

OBJECTIVE

To report the surgical outcome of retroperitoneoscopic hand‐assisted laparoscopic nephroureterectomy (LNU) with bladder cuff excision for upper urinary tract transitional cell carcinoma (TCC), and to compare the outcome with that of the open procedure (ONU).

PATIENTS AND METHODS

From January 1998 to January 2003, 145 patients with upper urinary tract TCC were enrolled in the study; 87 had ONU and 58 retroperitoneoscopic hand‐assisted LNU. The specimens were reviewed by experienced pathologists to confirm the pathological stage. Operative duration, intraoperative blood loss, bowel recovery, analgesic use, hospital stay and time to convalescence were compared for both groups. The Mann–Whitney U‐test and Fisher's exact test were used for statistical analysis.

RESULTS

The mean follow‐up for ONU and LNU was 35.1 and 16.0 months, the mean operative duration 230.2 and 259.1 min (P = 0.006), the mean blood loss 747.3 and 408.9 mL (P < 0.001), the mean duration of Foley catheterization 6.8 and 5.1 days (P < 0.001), and the hospital stay 12.6 and 9.3 days (P < 0.001). The bladder recurrence rate 2 years after surgery was 9.1% for ONU and 8.6% for LNU (P = 0.23); the local recurrence rate during the follow‐up was 3.4% and none, respectively (P = 0.35).

CONCLUSION

Although LNU took longer than ONU the intraoperative bleeding and hospital stay were better than for ONU. Both procedures have statistically comparable bladder recurrence and local recurrence rates.
Feasibility of radical perineal prostatectomy under spinal anaesthesia
Authors: Fichtner Jan , Mengesha Dagnew , Hutschenreiter Gert , Scherer Ralf
Published: October 2004

OBJECTIVE

To evaluate the possibility of a perineal radical prostatectomy (PRP) under spinal anaesthesia, as although it is usually done under general anaesthesia, there is currently a need to minimize costs and morbidity.

PATIENTS AND METHODS

Between January and December 2003, there were 337 PRPs at our institution, of which 47 were on patients under combined spinal/epidural (CSE) anaesthesia administered via a standard L3/4 or L4/5 approach. We analysed the feasibility of PRP under CSE and evaluated perioperative morbidity, including blood loss and hospital stay.

RESULTS

All 47 procedures were done under CSE with no need for conversion to general anaesthesia. The mean (range) duration of PRP was 56 (43–112) min, the mean blood loss 270 mL, and the transurethral catheter was removed at 7 days in 40 and at 14 days in the remaining seven patients. There were no complications during surgery, e.g. rectal or ureteric lesions. The mean hospital stay was 8.2 days.

CONCLUSION

PRP is safe under CSE anaesthesia; this may be helpful in minimizing morbidity and medical costs, as well as providing an alternative in patients in whom general anaesthesia is not recommended.
Intravenous urography‐virtual cystoscopy is a better preliminary examination than air virtual cystoscopy
Authors: Kawai Noriyasu , Mimura Takeo , Nagata Daisuke , Tozawa Keiichi , Kohri Kenjiro
Published: October 2004

OBJECTIVE

To describe a new technique of virtual cystoscopy (VC, used previously but with catheterization to drain residual urine and insufflation with air or carbon dioxide) with no invasive catheterization, used in parallel with intravenous urography (IVU), as conventional cystoscopy is an invasive but essential examination, and VC with multislice computed tomography (CT) was introduced to make preliminary examinations noninvasive.

PATIENTS AND METHODS

Using multislice CT and a device with 16 rows of detectors, we examined five patients using VC that previously involved catheterization, termed ‘air VC’ and 16 using VC with the new technique, termed ‘IVU VC’. We assessed the new technique by evaluating the tumour detection rate, and merits and demerits of both types of VC.

RESULTS

The detection rate of bladder tumours by IVU VC was similar to that from air VC; moreover, IVU VC overcame two significant disadvantages of air VC, i.e. the appearance of the water surface and the need for catheterization.

CONCLUSION

Conventional cystoscopy is still an essential examination but this new method of IVU VC may be ideal for preliminary examination of the bladder.
Development and validation of a quality‐of‐life scale for Chinese patients with benign prostatic hyperplasia
Authors: Shi Jingcheng , Sun Zhenqiu , Cai Taisheng , Yang Louyan
Published: October 2004

OBJECTIVE

To develop and validate a quality of life (QoL) scale for Chinese patients with benign prostatic hyperplasia (BPH).

PATIENTS AND METHODS

According to the QoL definition of the World Health Organisation, we adhered to the rigorous guidelines of instrument development to form a pool of items, selected items and validated the scale, using data from 256 patients with BPH.

RESULTS

A 74‐item QoL scale for BPH (prior test version; BPH‐QLS), including five domains (disease, physical, social, psychological, satisfaction) was developed and had good reliability and validity. The test‐retest correlation coefficient and Cronbach's α coefficient of the BPH‐QLS were 0.892 and 0.966. Thirteen common factors were extracted according to the conceptual model. The correlations of the BPH‐QLS with the Short Form‐36, the International Prostate Symptom Score (IPSS), and IPSS QoL score, and a published BPH‐specific QoL scale were 0.784, 0.493, 0.462 and 0.762, respectively. The BPH‐QLS could be used to discriminate among patients with a different QoL.

CONCLUSION

The new scale is reliable, valid and sensitive, and we recommend using the BPH‐QLS in Chinese and Chinese‐born patients worldwide to assist in clinical practice.
An epidemiological study of renal pathology in tuberous sclerosis complex
Authors: O'Callaghan Finbar J. , Noakes Michael J. , Martyn Christopher N. , Osborne John P.
Published: October 2004

OBJECTIVES

To report the frequency of renal symptoms and complications of patients with tuberous sclerosis complex (TSC), to describe the ultrasonographic appearance of the kidneys in a population‐based sample, and to investigate the relationship between a history of renal haemorrhage and renal lesions identified by ultrasonography.

PATIENTS AND METHODS

As part of an epidemiological study, 179 patients with TSC were identified as living in the Wessex Region in the South of England. Patients were interviewed and examined in their homes, to elicit the presence of renal symptoms or a history of renal complications. Renal ultrasonography was used in consenting patients in their homes.

RESULTS

There was a history of renal complications in 16 (9%) patients; 149 consented to interview and examination, and 19 gave a history of renal symptoms in the previous year; 124 had renal ultrasonography; 86 (69%) had renal angiomyolipomas and 37 (30%) had renal cysts. Large lesions (>3 cm in diameter) were strongly associated with a history of symptomatic bleeding, although significant haemorrhage occurred in a 6‐year‐old child with small angiomyolipomas.

CONCLUSIONS

The formation of angiomyolipoma in TSC is common. Polycystic kidney disease, renal carcinoma and renal failure, although rare, occur in TSC. Most patients with angiomyolipomas have neither complications nor symptoms. There was no appreciable difference between the sexes in the risk of developing these lesions. Although less commonly seen in the very young, there is no identifiable relationship after adolescence between age and the risk of having a renal angiomyolipoma. Bleeding tends to occur from large lesions (>3 cm) but most such patients have remained asymptomatic to date.
In vitro assessment of decellularized porcine dermis as a matrix for urinary tract reconstruction
Authors: Kimuli Michael , Eardley Ian , Southgate Jennifer
Published: October 2004

The contribution by the units in York and Leeds to tissue‐engineering research is considerable, and they describe here their work to assess a natural matrix for use in the urinary tract, and to develop an in vitro regimen for assessing the biocompatibility of potential biomaterials. They describe how they have developed a simple, reproducible and rigorous regimen which will help to identify the causes of potential bio‐incompatibility.

Buccal mucosa has become the tissue of choice for urethroplasty. Authors from Edinburgh report on the oral complications after its harvesting; they found that most patients were satisfied with its use, but that it had long‐term complications, about which patients should be informed.

OBJECTIVES

To assess the potential of PermacolTM (Tissue Science Laboratories, Swillington, UK), a natural matrix derived from decellularized porcine dermis, as a matrix for urological tissue engineering, and thus to develop an in vitro regimen for assessing the biocompatibility of potential biomaterials before experimentation in animal models.

MATERIALS AND METHODS

Urinary tract‐derived normal human urothelial (NHU) and smooth muscle (SM) cells were grown in monoculture as autologous cell lines. Permacol was assessed for its ability to support colonization by NHU and SM cells. The failure of the Permacol matrix to be infiltrated by SM cells was further investigated using the highly invasive EJ bladder cancer cell line.

RESULTS

NHU cells readily attached and grew as a monolayer on the surface of Permacol. Cells stratified when the culture medium was supplemented with 2 mmol/L calcium. EJ cells initially grew on the surface and subsequently invaded the matrix, while SM cells only colonized the surface of Permacol when cocultured with NHU cells. Cytoxicity, evaluated by contact inhibition and conditioned‐medium assays, excluded the presence of soluble toxins in the biomaterial.

CONCLUSIONS

We developed a simple, reproducible and rigorous regimen for assessing potential biomaterials in vitro. Applying this system might reduce the use of animals and help to identify causes of potential bio‐incompatibility. The inability of SM cells to penetrate the Permacol matrix suggests that required matrix‐bound signalling factors are absent, possibly as a result of the procedures used for processing Permacol. Identifying the key regulatory factors that regulate SM cell growth and orchestrate regenerative processes in the urinary tract will be important for developing suitable biomaterials for the bladder.
Oral complications after buccal mucosal graft harvest for urethroplasty
Authors: Dublin Norman , Stewart Laurence H.
Published: October 2004

OBJECTIVE

To report long‐term oral complications after buccal mucosal graft (BMG) harvesting for urethroplasty.

PATIENTS AND METHODS

In a retrospective study of all patients who had BMG harvesting for urethroplasty from April 1996 to September 2002, telephone interviews were conducted using a standard proforma.

RESULTS

Thirty‐five patients were identified but only 30 (mean age 48.3 years, range 24–86) could be contacted; they had had 31 operations. Soon after surgery (the first 48 h), 22 (73%) of the patients had little or no oral pain; 70% and 90% of the patients were able to eat and drink, respectively; 59% complained of numbness and 75% complained of tightness of the mouth. At discharge 6 days after surgery 90% of patients had little or no oral pain and all were able to eat and drink, but 10% had moderate‐to‐severe oral pain, 39% had oral numbness, and 52% had tightness of the mouth. At the time of interview, 16% of patients had oral numbness (mean duration 13.6 months) and 32% had tightness of the mouth (mean duration 20.9 months). In answer to the question of whether they would have their cheek mucosa harvested again if required, 74% responded ‘yes’, 3%‘no’, and 23% had mixed feelings.

CONCLUSIONS

BMG harvesting is a good operation, as most patients were satisfied, but it is not without long‐term complications and patients should be adequately informed.
Plaque incision and grafting as a salvage after a failed Nesbit procedure for Peyronie's disease
Authors: Muneer Asif , Kalsi Jas , Christopher Nim , Minhas Suks , Ralph David J.
Published: October 2004

OBJECTIVE

To analyse the outcome of plaque incision and grafting in patients who have a residual penile deformity after a Nesbit procedure for Peyronie's disease, as a further Nesbit procedure may present difficulties in dissection at the previous operative site, and may result in further penile shortening.

PATIENTS AND METHODS

Over a 5‐year period, 15 patients (mean age 58 years, range 34–66) presented with a residual penile deformity after a Nesbit procedure. All the patients had painless and stable Peyronie's disease. All patients had the Peyronie's plaque incised and grafted with either saphenous vein (12) or modified human fascia lata (three). The outcome was assessed using criteria which recorded the degree of penile shortening, quality of erections and penile angulation.

RESULTS

Before surgery the mean (range) angle of deformity was 56 (40–90)°; at a mean follow‐up of 10 (3–16) months 11 patients had a straight penis, three a residual angle of 10–30° and one had no change in angle. Two patients reported penile shortening and one a new onset of erectile dysfunction. Overall, 14 patients reported either an excellent or satisfactory result.

CONCLUSIONS

These results indicate that plaque incision and grafting is an effective salvage operation to correct a residual penile deformity after a failed Nesbit procedure in patients with Peyronie's disease.
Are published normal ranges of serum testosterone too high? Results of a cross‐sectional survey of serum testosterone and luteinizing hormone in healthy men
Authors: Boyce Malcolm J. , Baisley Kathy J. , Clark Elizabeth V. , Warrington Steven J.
Published: October 2004

OBJECTIVE

To derive normal ranges of serum testosterone and luteinizing hormone (LH) concentrations in healthy men, and thus evaluate whether testosterone replacement therapy is prescribed inappropriately.

SUBJECTS AND METHODS

The study comprised 266 healthy male volunteers (aged 18–75 years) who were defined as healthy by strict eligibility criteria. Subjects had a body mass index (BMI) of 18.6–32.2 kg/m2, smoked 0–10 cigarettes/day, and had an alcohol intake 0–40 units/week (one unit = 8 g ethanol). We measured serum testosterone and LH concentrations in the morning (08.00–09.00 hours) and evening (20.00–21.00 hours).

RESULTS

Morning normal ranges of testosterone for men aged ≤ 40 years were 10.07–38.76 nmol/L (2.90–11.18 µg/L), and for men age ≥ 40 years, 7.41–24.13 (2.14–6.96); the respective evening normal ranges were 6.69–31.51 (1.93–9.09) and 6.46–21.93  (1.86–6.33). Both morning and evening serum testosterone declined significantly with increasing age and BMI. LH was significantly higher in the morning than in the evening, but did not vary between the age groups or with BMI. The calculated normal ranges of LH were 0.9–7.0 IU/L (morning) and 0.7–6.8 IU/L (evening).

CONCLUSIONS

The lower limit of normal for serum testosterone was 3–4 nmol/L (0.86–1.15 µg/L) lower than that of published ranges. The results have important implications for the diagnosis of hypogonadism and use of testosterone replacement therapy.
Interpretation of the renogram: problems and pitfalls in hydronephrosis in children
Authors: Eskild‐Jensen Anni , Gordon Isky , Piepsz Amy , Frøkiær Jørgen
Published: October 2004

The role of diuretic renography has become central in cases of upper tract dilatation, and in the first paper in this section the difficulties in interpreting results in asymptomatic congenital hydronephrosis are examined. These difficulties and controversies exist despite the presence of guidelines and consensus protocols, probably because renography procedures differ among centres. The authors found that there is a need for renography to be standardized for the optimum value to be obtained from the procedure.

There are three papers from Los Angeles which attempt to standardize the measurement of bladder compliance, from both the theoretical and clinical perspective, and which assess the detrusor pressure rise of a normal bladder when filled to capacity.

OBJECTIVE

To discuss the main steps of renographic technique and underline some pitfalls related to the acquisition, processing and interpretation of diuretic renography, an important method for guiding the management of asymptomatic congenital hydronephrosis.

METHODS

Despite guidelines and consensus protocols, renographic procedures differ among centres, causing difficulties in comparison and controversy in the interpretation of results. Thus we comprehensively assessed published papers on the subject of diuretic renography.

RESULTS

Differential renal function (DRF) is a robust measure provided there is adequate background subtraction. Pitfalls are related to the drawing of regions of interest, particularly in infants, to estimating the interval during which DRF is calculated, and to an adequate signal‐to‐noise ratio. There is no definition of a ‘significant’ reduction in DRF. The classical variables of the diuretic renogram may not allow an estimate of the best drainage. Poor pelvic emptying may be apparent because the bladder is full and because the effect of gravity on drainage is incomplete. Estimating the drainage as residual activity rather than any parameter on the slope might be more adequate, especially if the time of frusemide administration is changed. Renal function and pelvic volume can influence the quality of drainage. Drainage may be better estimated using new tools.

CONCLUSION

Provided the investigation is standardized and potential pitfalls accounted for, the diuretic renogram provides valuable and reproducible quantitative information on DRF and drainage.
Quantitative morphometric analysis of individual resected prostatic tissue specimens, using immunohistochemical staining and colour‐image analysis
Authors: Phipps Simon , Habib Fouad K. , McNeill Alan
Published: October 2004

OBJECTIVE

To develop a method for obtaining morphometric measurements representative of individual chips from transurethral resection of the prostate (TURP).

MATERIALS AND METHODS

In all, 232 sections were cut in pairs from 25 TURP chips, collected from four patients undergoing TURP for benign prostatic hyperplasia. Individual tissue chips were processed, embedded in paraffin wax and pairs of neighbouring sections cut from the specimens at intervals of 300 µm throughout the thickness of the specimen. Of each pair, the epithelial tissue (ET) of one and the smooth muscle (SM) of the other section were stained immunohistochemically with anti‐prostate‐specific antigen and anti‐SM myosin, respectively. Proportions of ET and SM within the sections were measured with colour‐image analysis and calculated within the TURP chips using all pairs of sections cut from the specimen, and the first pair of sections only. The differences between the sets of results were analysed using descriptive statistics.

RESULTS

From each TURP chip, 3–7 pairs of sections were cut; for both ET and SM within each chip the differences between the results calculated using data from all pairs of sections and the first pair alone were small, as were the distributions of these differences within each prostate.

CONCLUSIONS

Morphometric measurements from one section from a processed TURP chip, as opposed to serial sections, can be used to reliably assess the morphology of tissue within that specimen. This permits a considerable saving of resources when undertaking morphometric image analysis of resected prostatic tissue specimens.
Denudation history of the high T/P Ryoke metamorphic belt, southwest Japan: constraints from CHIME monazite ages of gneisses and granitoids
Authors: SUZUKI K. , ADACHI M.
Published: October 2004

CHIME (chemical Th–U‐total Pb isochron method) monazite ages were determined for gneisses and granitoids from the eastern and western parts of the Ryoke belt separated by about 500 km. The monazite ages for the gneisses are concentrated between 102 and 98 Ma, and are interpreted as the time of monazite formation under lower amphibolite facies conditions. The peak metamorphism seems to be contemporaneous with the emplacement of the geologically oldest plutons that are dated at c. 95 Ma in both the eastern and western parts. In the eastern part plutonism continued from c. 95 Ma to c. 68 Ma at intervals of 2–10 Ma, whereas in the western part it ceased at c. 85 Ma. The CHIME monazite ages agree well with the relative age of granitoids derived from intrusive relationships of granitoids in both parts. These lines of evidence are incompatible with a current view that the plutonometamorphism in the Ryoke belt becomes younger towards the east. The CHIME monazite ages, coupled with available data on the depth at which the Ryoke metamorphism took place and the emplacement of individual plutons, show that the western part was eroded more rapidly (about 1.5 mm year−1) than the eastern part (about 0.8 mm year−1) over the time span from 91 to 85 Ma. The denudation rates agree well with those in active orogenic belts like the Alps and Himalayas.
Pressure‐temperature path of Sanbagawa prograde metamorphism deduced from grossular zoning of garnet
Authors: ENAMI M.
Published: October 2004

The zonal structure of prograde garnet in pelitic schists from the medium‐grade garnet zone and the higher‐grade albite‐biotite zone was examined to investigate the evolution of prograde P–T  paths of the Sanbagawa metamorphism. The garnet studied shows a bell‐shaped chemical zoning of the spessartine component, which decreases in abundance from the core towards the rim. Almandine and pyrope contents and XMg [=Mg/(Mg+Fe2+)] increase monotonously outwards. The general scheme of the zonal structure for grossular content [XGrs=Ca/(Fe2++Mn+Mg+Ca)] can be summarized as: (1) XGrs increases outwards (inner segment) and reaches a maximum at an intermediate position between the crystal core and the rim, then decreases towards the outermost rim (outer segment) (2) the inner segment of garnet in the garnet zone samples tends to have a higher XGrs/XSps values for a given XSps than those in the albite–biotite zone samples (3) average XSps at the maximum XGrs position in the albite–biotite zone samples ranges from 0.02 to 0.12 and is lower than that in the garnet zone samples (0.13–0.32) (4) the maximum XGrs in the albite–biotite zone samples (0.34–0.39 on average) tends to be higher than that in the garnet zone samples (0.26–0.36), and (5) differences of XGrs between the maximum and rim in the albite–biotite zone samples are between 0.10 and 0.14 and higher than those in the garnet zone samples (< 0.11). These facts imply that albite–biotite zone materials (a) were recrystallized under lower dP/dT  conditions at an early stage of the prograde metamorphism (b) began their exhumation under higher P–T  conditions and (c) have been continuously heated during exhumation for a longer duration than the garnet zone materials. The systematic changes of prograde P–T  paths can be interpreted as documenting the evolution of the Sanbagawa subduction zone.
Progressive sequence of reactions of the Ryoke metamorphism in the Yanai district, southwest Japan: the formation of cordierite
Authors: IKEDA T.
Published: October 2004

The compositions of biotite and muscovite were examined in terms of the paragenesis and the metamorphic grade in low‐ to medium‐grade pelitic rocks of the Ryoke metamorphism in the Yanai district, southwest Japan. The biotite and muscovite that coexist with K‐feldspar have a higher K component in an A′KF diagram than those in rocks lacking K‐feldspar. This fact reflects an increase in the K2O content in muscovite, but in biotite it reflects an increase of not only the K2O content but also of the octahedral vacancy.

At higher metamorphic grade beyond the cordierite isograd, where cordierite coexists with neither chlorite nor K‐feldspar, the biotite shows an increase in illite, K Aliv □xii−1 Si−1, and Tschermak components, Alvi Aliv R+−1 Si−1, where □xii and R+ denote the interlayer vacancy and (Fe+Mg+Mn), respectively. A reaction to define the cordierite isograd is proposed by treating this chemical change as being responsible for the first appearance of cordierite, i.e. K,Al‐poor biotite+phengitic muscovite=K,Al‐rich biotite+cordierite+quartz+water .By treating this as a key reaction in medium‐grade metamorphism, a set of reaction in a progressive metamorphism is established for the Ryoke metamorphism, a typical low‐pressure type metamorphism. Some textures in one of the high‐grade areas, the K‐feldspar‐cordierite zone, suggest that a further two prograde reactions have taken place, i.e. andalusite+biotite+quartz=cordierite+K‐feldspar+water

and  andalusite=sillimanite.quartz=cordierite+K‐feldspar+water

This implies that this zone probably has a P–T  path involving isobaric heating.
Sapphirine‐bearing granulites and related high‐temperature metamorphic rocks from the Higo metamorphic terrane, west‐central Kyushu, Japan
Authors: OSANAI Y. , HAMAMOTO T. , MAISHIMA O. , KAGAMI H.
Published: October 2004

The Higo metamorphic unit in west‐central Kyushu island, southwest Japan is an imbricated crustal section in which a sequence of units with increasing metamorphic grade from high (northern part) to low (southern part) structural levels is exposed. The basal part of the metamorphic sequence representing an original depth of 23–24 km consists mainly of garnet–cordierite–biotite gneiss, garnet–orthopyroxene gneiss, orthopyroxene‐bearing amphibolite and orthopyroxene‐bearing S‐type tonalite. These metamorphic rocks underwent high amphibolite‐facies up to granulite facies metamorphism with peak P–T  conditions of 720 MPa, 870 °C. In addition sapphirine‐bearing granulites and related high‐temperature metamorphic rocks also occur as tectonic blocks in a metamorphosed peridotite intrusion. The sapphirine‐bearing granulites and their related high‐temperature metamorphic rocks can be subdivided into five types of mineral assemblages reflecting their bulk chemical compositions as follows: (1) sapphirine–corundum–spinel–cordierite (2) corundum–spinel–cordierite (3) garnet–corundum–spinel–cordierite (4) garnet–spinel–gedrite–corundum, and (5) orthopyroxene–spinel–gedrite. These metamorphic rocks are characterized by unusually high Al2O3 and low SiO2 contents, which could represent a restitic nature remaining after partial melting of pelitic granulite under the ultra high‐temperature contact metamorphism at the peak metamorphic event of the Higo metamorphic unit. The metamorphic conditions are estimated to be about 800 MPa and above 950 °C which took place at about 250 Ma as a result of the thermal effect of the regional gabbroic rock intrusions.
Exhuming the Sanbagawa metamorphic belt: the importance of tectonic discontinuities
Authors: WALLIS S.
Published: October 2004

Tectonic processes that have been proposed to explain the transport to the surface of regional metamorphic belts can be broadly divided into two types. (i) Corner‐flow within a convergent margin bounded by two essentially rigid plates associated with extension at shallow levels. This type of model assumes deformation is distributed throughout the margin and that any discontinuities are of secondary importance. (ii) Expulsion or extrusion of coherent metamorphic nappes. In this second idea, tectonic discontinuities are fundamental in the transport to the surface of metamorphic rocks. The wealth of geological data available from a variety of studies in the Sanbagawa metamorphic belt, southwest Japan makes it well‐suited for studying the relative importance of continuous vs. discontinuous deformation in the process of exhumation. In the Sanbagawa belt a sudden decrease in metamorphic pressure going down section of several kilobars suggests the presence of a major tectonic contact separating two major regional nappes: an overlying higher‐pressure Besshi nappe and an underlying lower‐pressure Oboke nappe. Major tectonic discontinuities have also been proposed within the Besshi nappe, however, indicators of metamorphic temperature, the results of radiometric age dating, and microstructural studies all suggest that post‐metamorphic discontinuities are minor and that this nappe formed and remained as an essentially coherent unit. Lithological associations and petrological studies suggest the following positions for the two nappes. The Besshi nappe formed deep within the former accretionary wedge, adjacent to the overlying mantle wedge, and with a dip of roughly 30 °C. In contrast, the Oboke nappe formed at moderate depths within the accretionary wedge, was distant from the mantle wedge, and was roughly horizontal. Penetrative deformation that post‐dates the peak of metamorphism has affected nearly all of the Sanbagawa belt and has played an important role in its exhumation. However, the presence of a broad coherent Besshi nappe overlying the lower‐pressure Oboke nappe suggests that some process such as buoyancy‐driven extrusion was also important in the exhumation process and in forming the structure of the Sanbagawa metamorphic belt.
SHRIMP monazite and zircon geochronology of high‐grade metamorphism in New Zealand
Authors: IREL T. R. , GIBSON G. M.
Published: October 2004

Ion microprobe dating of zircon and monazite from high‐grade gneisses has been used to (1) determine the timing of metamorphism in the Western Province of New Zealand, and (2) constrain the age of the protoliths from which the metamorphic rocks were derived. The Western Province comprises Westland, where mainly upper crustal rocks are exposed, and Fiordland, where middle to lower crustal levels crop out. In Westland, the oldest recognisable metamorphic event occurred at 360–370 Ma, penecontemporaneously with intrusion of the mid‐Palaeozoic Karamea Batholith (c. 375 Ma). Metamorphism took place under low‐pressure/high‐temperature conditions, resulting in upper‐amphibolite sillimanite‐grade metamorphism of Lower Palaeozoic pelites (Greenland Group). Orthogneisses of younger (Cretaceous) age formed during emplacement of the Rahu Suite granite intrusives (c. 110 Ma) and were derived from protoliths including Cretaceous Separation Point suite and Devonian Karamea suite granites. In Fiordland, high‐grade paragneisses with Greenland Group zircon age patterns were metamorphosed (M1) to sillimanite grade at 360 Ma. Concomitant with crustal thickening and further granite emplacement, M1 mineral assemblages were overprinted by higher‐pressure kyanite‐grade metamorphism (M2) at 330 Ma. It remains unclear whether the M2 event in Fiordland was primarily due to tectonic burial, as suggested by regional recumbent isoclinal folding, or whether it was due to magmatic loading, in keeping with the significant volumes of granite magma intruded at higher structural levels in the formerly contiguous Westland region. Metamorphism in Fiordland accompanied and outlasted emplacement of the Western Fiordland Orthogneiss (WFO) at 110–125 Ma. The WFO equilibrated under granulite facies conditions, whereas cover rocks underwent more limited recrystallization except for high‐strain shear zones where conditions of lower to middle amphibolite facies were met. The juxtaposition of Palaeozoic kyanite‐grade rocks against Cretaceous WFO granulites resulted from late Mesozoic extensional deformation and development of metamorphic core complexes in the Western Province.
Fluid infiltration and volume change during mid‐crustal mylonitization of Proterozoic granite, King Island, Tasmania
Authors: STREIT* J. E. , COX* S. F.
Published: October 2004

The development of 10–30 m wide mylonite zones at mid‐crustal depths in late Proterozoic granitoids on King Island, Tasmania, was associated with pervasive infiltration of low δ18O‐fluids (+5 to +7) on the scale of the shear zones. Syndeformational fluid–rock interaction produced substantial differences in mineral composition and bulk rock chemistry among several adjacent shear zones which are hosted by the same granite. In a shear zone at Cape Wickham with a normal slip component, changes in whole‐rock chemistry between granite and mylonites indicate a gain of Ca, and losses of K and Na during deformation, which was nearly isovolumetric. Notable losses of K, Rb and Si occurred during partial retrograde alteration of mylonites near the western margin of this shear zone. The alteration suggests a component of up‐temperature fluid flow. In contrast, 3 km to the south east, in a strike‐slip shear zone at Disappointment Bay, complete albitization of plagioclase was associated with Na‐gain and Ca‐loss. Deformation also involved losses of Mg and Fe. Up to 60% volume gain occurred during the formation of closely spaced mesoscopic to microscopic quartz veins during mylonitization. The substantial silica‐gain in this, as well as in two mylonite zones further south east, is interpreted to have been associated with upward flow of aqueous fluids along these shear zones. On the basis of a gradient reaction model, minimum time‐integrated fluid‐fluxes of 106 m3/m2 are estimated for the Disappointment Bay (West) Shear Zone.
Singularities in NCKFMASH (Na2O–CaO–K2O–FeO–MgO–Al2O3–SiO2–H2O)
Authors: WORLEY* B. , POWELL R.
Published: October 2004

A new petrogenetic grid is presented for the system NCKFMASH (Na2O–CaO–K2O–FeO–MgO–Al2O3–SiO2–H2O), in which Ca is incorporated in garnet, and CaAlNa−1Si−1 solid solution is considered for both the plagioclase and white‐mica structures. A compatibility diagram for plagioclase‐bearing metapelitic assemblages within the NCKFMASH system also has been derived. A dominant feature of the NCKFMASH grid is the singularities and associated singular reactions which occur along plagioclase+margarite‐ and plagioclase+paragonite‐bearing univariant equilibria. The singularities represent compositional coplanarities which occur in response to the CaAlNa−1Si−1 substitution occurring at different rates in plagioclase and white‐mica. This is controlled by a fundamental difference in the mixing within the two mineral structures. The singularities give rise to a number of intriguing phase diagram features, including azeotropes. From the results presented here, it is predicted that the occurrence of margarite and paragonite in pelitic rocks is controlled by equilibria related to the singularities. The presence of these white‐micas is strongly dependent upon bulk composition, and plagioclase‐bearing, margarite/paragonite‐free assemblages, typical of Barrovian‐type terranes, are predicted for bulk compositions of Mg/(Mg+Fe)≈0.4 and Ca/(Ca+Na)≈0.4 at for example 5.5 kbar.
Structural boundaries and biotite and garnet ‘isograds’ in the Otago and Alpine Schists, New Zealand
Authors: CRAW D.
Published: October 2004

The Otago and Alpine Schist belts of southern New Zealand have traditionally been treated as structurally continuous metamorphic belts with minor modification by brittle faulting. Mapping of biotite and garnet isograds has been hindered by rock types unfavourable for index mineral growth. Closer examination of well‐exposed boundaries between metamorphic zones shows that they juxtapose rocks of different type and structural history. Apparent structural continuity across these zones is due to development of a locally pervasive boundary‐parallel foliation on both sides of the boundary, in a broad boundary zone (up to 2 km wide). This feature has implications for mapping and metamorphic petrology in other metamorphic belts, where structural continuity has traditionally been assumed. True metamorphic isograds may be rare, and metamorphic zones may more commonly represent structural slices of complex, tectonically disrupted metamorphic piles.
Dating synmagmatic folds: a case study of Schlingen structures in the Strona‐Ceneri Zone (Southern Alps, northern Italy)
Authors: ZURBRIGGEN R. , KAMBER B. S. , HANDY M. R. , NÄGLER T. F.
Published: October 2004

The Strona‐Ceneri Zone (Southern Alps) contains folds with moderately to steeply inclined axial planes and fold axes, and amplitudes of up to several kilometres (so‐called ‘Schlingen’). These amphibolite facies folds deform the main schistosity of Late Ordovician metagranitoids and are discordantly overlain by unmetamorphic Permian sedimentary rocks. Mutually cross‐cutting relationships between these folds and garnet‐bearing leucotonalitic dykes indicate that these dykes were emplaced during folding. Sm–Nd systematics and the strongly peraluminous composition of these dykes point to an anatectic origin. Pb step leaching of magmatic garnet from a leucotonalitic dyke yielded a 321.3±2.3 Ma intrusive age. Rb–Sr ages on muscovites from leucotonalitic dykes range from 307 to 298 Ma, interpreted as cooling ages during retrograde amphibolite facies metamorphism. Conventional U–Pb data of zircons from an older granodioritic dyke that pre‐dates the Schlingen folds yielded discordant U–Pb ages ranging from 371 to 294 Ma. These ages reflect a more complicated multi‐episodic growth history which is consistent with the observed polyphase structural overprint of this dyke. Schlingen folding was accompanied by prograde amphibolite facies metamorphism, during the thermal peak of which the leucotonalitic dyke material was generated by partial melting in a deeper source region from where these S‐type magmas intruded the presently exposed level. Because partial melting may occur in a relatively late stage of a clockwise P–T–t path, or even during decompression on the retrograde path, we do not exclude the possibility that Schlingen folding had already started in Early Carboniferous time. Schlingen folds also occur in Penninic and Austroalpine basement units with a very similar pre‐Alpine history, indicating that Variscan folding affected large segments of the future Alpine realm.
Early Tertiary eclogite facies metamorphism in the Monviso Ophiolite
Authors: CLIFF (email: ) R. A. , BARNICOAT A. C. , INGER S.
Published: October 2004

Although crucial for the construction of tectonic models of the Alps the timing of high pressure metamorphism is still poorly determined and controversial. It is likely to vary from one tectonic unit to another depending on when each became involved in subduction. This in turn relates to palaeogeographic position with respect to the active ocean basin. Well defined, reliable geochronological data are too few to test this hypothesis. This paper extends the database by determining Sm–Nd mineral isochrons on two samples from the Monviso Ophiolite in the Piemonte Zone, carefully selected to minimize the problems of Sm–Nd dating of eclogites encountered elsewhere in the Alps. The dated samples have eclogite facies mineral assemblages typical of the Lago Superiore unit of the ophiolite; mineral compositions are similar to previously reported samples and indicate pressures of around 2 GPa and temperatures of 400–500 °C. Sm–Nd isochron ages of 60±12 and 62±9 Ma are defined by garnet and clinopyroxene, while the Rb–Sr age on phengite which is part of the high‐P assemblage is 40±1 Ma. The new data fit an emerging pattern of ages in which high‐P metamorphism in the oceanic realm is Early Tertiary, with slightly older ages in the overlying Sesia Zone and younger, Oligocene ages in the underlying internal basement massifs which only became involved in subduction when closure of the Piemont ocean was complete.
Calculating phase diagrams involving solid solutions via non‐linear equations, with examples using THERMOCALC
Authors: POWELL R , HOLLAND T. , WORLEY B.
Published: October 2004

Phase diagrams involving solid solutions are calculated by solving sets of non‐linear equations. In calculating P–T  projections and compatibility diagrams, the equations used for each equilibrium are the equilibrium relationships for an independent set of reactions between the end‐members of the phases in the equilibrium. Invariant points and univariant lines in P–T  projections can be calculated directly, as can coordinates in compatibility diagrams. In calculating P–T  and T–x/P–x pseudosections – diagrams drawn for particular bulk compositions – the equilibrium relationship equations are augmented by mass balance equations. Lines in pseudosections, where the mode of one phase in the lower variance equilibrium is zero, and points, where the modes of two phases are zero, can then be calculated directly. The software, THERMOCALC, allows the calculation of these and a range of other types of phase diagram. Examples of phase diagrams and phase diagram movies, with instructions for their production, along with the THERMOCALC input and output files, and the MathematicaTM functions for assembling them, are presented in this paper, partly in hard copy and partly on the JMG web sites (http://www.gly.bris.ac.uk/www/jmg/jmg.html, or equivalent Australian or USA sites).
Prograde eclogite in the Gföhl Nappe, Czech Republic: new evidence on Variscan high‐pressure metamorphism
Authors: MEDARIS L. G. , FOURNELLE J. H. , GHENT E. D. , JELÍNEK E. , MÍSAŘ Z.
Published: October 2004

A layer of relict, high‐temperature, prograde eclogite has been discovered within felsic granulite of the Gföhl Nappe, which is the uppermost tectonic unit in the Moldanubian Zone of the Bohemian Massif, the easternmost of the European Variscan massifs. Pressure‐temperature conditions for eclogite (≥890 °C, 18.0 kbar) and felsic granulite (c. 1000 °C, 16 kbar) place early metamorphism of the polymetamorphic Gföhl crustal rocks within the eclogite facies, and preservation of prograde compositional zoning in small garnet grains in high‐temperature eclogite requires very rapid heating, as well as cooling. Mantle‐derived garnet and spinel–garnet peridotites are associated with the high temperature‐high pressure crustal rocks in the Gföhl Nappe, and this distinctive lithological suite appears to be unique among European Phanerozoic orogenic belts, implying that tectonic processes during the late stages in evolution of the Variscan belt were different from those in the Caledonian and Alpine belts. The unusually high temperatures and pressures in Gföhl crustal rocks, mineralogical evidence for rapid heating and cooling, juxtaposition of lithospheric and asthenospheric mantle with crustal rocks, and widespread production of late‐stage granites indicate that culmination of the Variscan Orogeny may have been driven by lithospheric delamination and asthenospheric upwelling.
Exosome Secretion: The Art of Reutilizing Nonrecycled Proteins?
Authors: de Gassart Aude , Géminard Charles , Hoekstra Dick , Vidal Michel
Published: October 2004

Multivesicular bodies contain membrane vesicles which either undergo lysosomal digestion or are released in the extracellular environment as exosomes. Evidence is accumulating that supports a physiological role for exosomes in, for example, antigen presentation or removal of transferrin receptor during reticulocyte development. Here, inspired by observations on exosomal release from reticulocytes, we discuss the potential involvement of the so‐called ESCRT mechanism in the entrapment of both lysosomal and exosomal cargo within the intralumenal vesicles of multivesicular bodies. We propose that this mechanism operates at different sites in the endocytic itinerary in different cells, thereby providing a tool for directional sorting. We also explore the possibility that the efficiency of sorting of molecules into exosomes increases when the recycling kinetics of molecules decreases, exosomal sorting being favored by intermolecular interactions occurring within lipid domains, or with protein webs, that slow lateral mobility. These considerations are mirrored in the context of current knowledge on the mechanism of protein sorting for degradation in lysosomes, and the hijacking of such mechanisms by some retroviruses for particle budding.
A Cure for Traffic Jams: Small Molecule Chaperones in the Endoplasmic Reticulum
Authors: Römisch Karin
Published: October 2004

Folding in the endoplasmic reticulum is the limiting step for the biogenesis of most secretory pathway cargo proteins; proteins which fail to fold are initially retained in the endoplasmic reticulum and subsequently often degraded. Mutations that affect secretory protein folding have profound phenotypes irrespective of their direct impact on protein function, because they prevent secretory proteins from reaching their final destination. When unicellular organisms are stressed by fluctuation of temperature or ionic strength, they synthesize high concentrations of small molecules such as trehalose or glycerol to prevent protein denaturation. These osmolytes can also stabilize mutant secretory proteins and allow them to pass secretory protein quality control in the endoplasmic reticulum. Specific ligands and cofactors such as ions, sugars, or peptides have similar effects on specific defective proteins and are beginning to be used as therapeutic agents for protein trafficking diseases.
Accessibility of mid‐segment domain IV S6 residues of the voltage‐gated Na+ channel to methanethiosulfonate reagents
Authors: Sunami Akihiko , Tracey Arlene , Glaaser Ian W. , Lipkind Gregory M. , Hanck Dorothy A. , Fozzard Harry A.
Published: October 2004

The inner pore of the voltage‐gated Na+ channel is predicted by the structure of bacterial potassium channels to be lined with the four S6 α‐helical segments. Our previously published model of the closed pore based on the KcsA structure, and our new model of the open pore based on the MthK structure predict which residues in the mid‐portion of S6 face the pore. We produced cysteine mutants of the mid‐portion of domain IV‐S6 (Ile‐1575–Leu‐1591) in NaV1.4 and tested their accessibility to intracellularly and extracellularly placed positively charged methanethiosulfonate (MTS) reagents. We found that only two mutants, F1579C and V1583C, were accessible to both outside and inside 2‐(aminoethyl)‐methanethiosulfonate hydrobromide (MTSEA) Further study of those mutants showed that efficient closure of the fast inactivation gate prevented block by inside [2‐(trimethylammonium)ethyl]methanethiosulfonate bromide (MTSET) at slow stimulation rates. When fast inactivation was inhibited by exposure to anthropleurin B (ApB), increasing channel open time, both mutants were blocked by inside MTSET at a rate that depended on the amount of time the channel was open. Consistent with the fast inactivation gate limiting access to the pore, in the absence of ApB, inside MTSET produced block when the cells were stimulated at 5 or 20 Hz. We therefore suggest that the middle of IV‐S6 is an α‐helix, and we propose a model of the open channel, based on MthK, in which Phe‐1579 and Val‐1583 face the pore.