Carbon-11-NNC 112: a radioligand for PET examination of striatal and neocortical D1-dopamine receptors

The aim of this work was to explore the potential of a selective D1-dopamine receptor antagonist as a new radioligand for PET examination of striatal and neocortical D1-dopamine receptors.

METHODS

The active (+)- and inactive (-)-enantiomers of [11C]NNC 112 were radiolabeled using the N-methylation approach and were examined by PET in cynomolgus monkeys and healthy men. Metabolite levels in plasma were measured by gradient high-performance liquid chromatography (HPLC).

RESULTS

N-methylation of the corresponding desmethyl precursors with [11C]methyl triflate gave high total radiochemical yield (50%-60%) and specific radioactivity (110 GBq/micromol). (+)-[11C]NNC 112 binding in cynomolgus monkeys was 5.77+/-0.31 and 2.36+/-0.14 times higher in the striatum and neocortex, respectively, than in the cerebellum at a transient equilibrium that appeared 40-50 min after injection. The binding of (+)-[11C]NNC 112 is stereoselective, because the brain distribution of the inactive (-)-enantiomer was on an equally low level for all brain regions. Displacement and pretreatment experiments using unlabeled SCH 23390 and ketanserin confirms that (+)-[11C]NNC 112 binds specifically and reversibly to D1-dopamine receptors. The radioactivity ratios of the striatum, frontal cortex and nucleus accumbens to the cerebellum were 3.8-4.0, 1.7-2.0 and 2.8-3.1, respectively, at a transient equilibrium that appeared 40-50 min after injection in four healthy human subjects. Linear graphical analysis gave distribution volume ratios of 3.9 and 1.5 in the putamen and frontal cortex, respectively. The fraction of the total radioactivity in human plasma representing unchanged (+)-[11C]NNC 112 was 85% at 5 min and 25% at 75 min after injection.

CONCLUSION

(+)-[11C]NNC 112 should be a useful PET radioligand for quantitative examination of not only striatal but neocortical D1-dopamine receptors in man.

Cubital tunnel syndrome: diagnosis by high-resolution ultrasonography

The purpose of this study was to evaluate the morphologic changes in the ulnar nerve in cubital tunnel syndrome with high-resolution ultrasonography. The mean values of the short axis (cm) x long axis (cm) at the arm, epicondyle, and forearm levels were 0.057 +/- 0.01, 0.068 +/- 0.019, and 0.062 +/- 0.01 in control group; 0.069 +/- 0.04, 0.139 +/- 0.06, and 0.066 +/- 0.023 in the symptomatic side in patients with cubital tunnel syndrome; and 0.063 +/- 0.029, 0.068 +/- 0.029, and 0.057 +/- 0.012 in the normal side in patients with cubital tunnel syndrome. No significant difference was found in the area (short axis x long axis) of the ulnar nerve at the arm, epicondyle and forearm levels between the left and right ulnar nerve in the control group and between the control group and the normal side in symptomatic patients. However, the mean value of the area of the ulnar nerve at the epicondyle level in symptomatic patients was significantly larger than that of the control group and that of the contralateral side in patients, and the P value was less than 0.001. High resolution ultrasonography can detect morphologic changes in the ulnar nerve accurately, and it could therefore be useful as a screening and even follow-up modality in patients with cubital tunnel syndrome.

Thyroid dysfunction and nodular goiter in hemodialysis and peritoneal dialysis patients

OBJECTIVE

To investigate the prevalence of nodular goiter and thyroid dysfunction in uremic patients undergoing hemodialysis (HD) and peritoneal dialysis.

DESIGN

Cross-sectional study.

SETTING

Single dialysis unit and outpatient clinic.

PATIENTS

The study included 221 patients [143 HD and 78 continuous ambulatory peritoneal dialysis (CAPD) patients] along with 135 consecutively selected outpatients as controls.

MAIN OUTCOME MEASURES

Ultrasonography was used to detect patients' thyroid function and nodular goiter.

RESULTS

Nodular goiter was detected in 54.8% of the uremic patients and in 21.5% of the controls. Uremic patients had higher prevalence of thyroid dysfunction, which included reduced serum concentration of total T3, total T4, and free T4, and increased serum level of TSH. Hypothyroidism was also observed more frequently in uremic patients than in the control group (5.4% vs 0.7%, p < 0.05). Nodular goiter was more frequently found in females than in males (63.5% vs 48%, p < 0.05). Moreover, the prevalence of nodular goiter increased with age (p < 0.02) in uremic patients. Hemodialysis patients had a higher frequency of reduced total T3 level (46.9% vs 29.5%, p < 0.02). However, CAPD patients had lower T4 levels (6.23+/-1.82 microg/dL vs 7.15+/-1.99 microg/dL, p < 0.05).

CONCLUSION

Because of the high incidence of hypothyroidism and nodular goiter in uremic patients, screening of thyroid function and goiter detection with ultrasound should be considered in evaluation of end-stage renal disease patients.

Ultrasound-guided interventional procedures in splenic abscesses

The results of ultrasound (US)-guided interventional procedures over a period of 12 years in 21 consecutive patients with splenic abscess were reviewed. The interventional procedures were done with 21- or 18-gauge needles for aspiration of relatively small abscesses (< 3.5 cm) in eight patients and with an 8.3-9.0 French pigtail catheter for continuous drainage in 13 patients with larger abscesses (> or = 3.5 cm). In some patients, multiple abscesses were treated separately according to their various sizes. More than one catheterization were done in three patients because of detached catheter or recurrent abscesses. The interventional procedures were followed by at least eight weeks of appropriate antibiotic therapy. Only one patient had the complication of minimal subcapsular hematoma which needed no further treatment. All the patients had uneventful clinical courses. US-guided interventional procedure proved to be a treatment-of-choice for splenic abscess, and may avoid splenectomy by conserving the spleen.

Association of fungal colonization and invasive disease in very low birth weight infants

BACKGROUND

Fungi are common pathogens of nosocomial infections in the very low birth weight (VLBW) infants. The purpose of this study was to investigate the fungal colonization rate in VLBW infants and the association between fungal colonization and systemic fungal diseases.

MATERIALS

Between January 1, 1996, and December 31, 1996, 116 infants with birth weight < 1500 g admitted to the neonatal intensive care unit of Chang Gung Children's Hospital in the first day of life were included in this prospective study.

METHODS

Cultures from oropharynx, rectum, skin (groin and axilla), bag urine and endotracheal aspirates were obtained in the first 24 h after birth and weekly thereafter throughout their neonatal intensive care unit stay. Medical records were reviewed weekly.

RESULTS

Fungal colonization was detected in 25 infants, among whom 17 infants developed colonization by 2 weeks of life. Candida albicans (61%) and Candida parapsilosis (29%) were the 2 most common organisms. The rectum (76%) was the most frequent site of colonization. Factors significantly associated with colonization were prolonged administration of antibiotic therapy, parenteral nutrition and intralipid emulsion. Three of 116 infants developed fungemia. The association between colonization and subsequent fungemia was demonstrated in 1 infant, representing 4% of colonized infants.

CONCLUSION

Fungal colonization was detected in one-fifth of VLBW infants and represents a risk factor for fungemia. Because disease occurred in the absence of apparent colonization, factors other than colonization may contribute to invasive candidiasis.

K-ras codon 12 mutation determines the polypoid growth of colorectral cancer

Colorectal carcinogenesis is widely thought to follow the adenoma-adenocarcinoma sequence. However, there are two morphologically distinct subtypes of colorectal cancer (CRC), polypoid and ulcerative. We conducted a comparative study to clarify whether different combinations of some commonly involved genetic alterations (including mutations in K-ras, p53, DCC, APC, and Rb genes) may exist between polypoid- and ulcerative-type CRCs, the two morphologically distinct types of CRC. By using PCR-based RFLP, single-strand conformational polymorphism, and loss of heterozygosity analysis, we found that K-ras codon 12 mutation was preferentially involved in polypoid tumor (P < 0.0001). There were no other significant correlations with p53 point mutation or loss of heterozygosity in chromosomes 5q, 17p, and 18q and Rb gene, which have been suggested to be involved in the progression of CRC of both morphological types. Therefore, different combinations of molecular genetic alterations may be involved in morphologically distinct types of colorectal carcinogenesis, and the K-ras codon 12 mutations may play an important role in polypoid growth of CRC. These results shed light on the function of K-ras oncogenes involved in colorectal carcinogenesis and may be important in the future design of genetic screening programs, determination of prognosis, and treatment for patients with CRC.

Clinical application of the measurement of cord plasma lactate and pyruvate in the assessment of high-risk neonates

Lactate levels in combination with lactate/pyruvate (L/P) ratio have been used to measure altered cellular redox states. We measured the cord plasma lactate levels and L/P ratios in 70 normal neonates (40 full-term and 30 preterm neonates) to set up the normal (control) ranges. The control cord plasma lactate levels and L/P ratios were 2660 [700 (SD)] micromol/l, 16 (3) in full-term neonates and 2750 (740) micromol/l, 17 (3) in preterm neonates, respectively. We also measured the lactate levels and L/P ratios in the high-risk full-term (n = 23) and preterm (n = 35) neonates, the results were 4500 (2600) micromol/l, 19 (13), and 5100 (2700) micromol/l, 26 (12), respectively. With the aid of elevated lactate levels and L/P ratios, the occurrence of neonatal encephalopathy can be predicted with a sensitivity of 100% and a specificity of 94.5% in this patient group. In our study, the six cases with abnormal neurodevelopment at 6-9 months of age all had both elevated lactate levels and L/P ratios at birth. We conclude that the measurement of lactate levels in combination with L/P ratios is a useful quantitative tool in assessing the existence and severity of perinatal hypoxia in the high-risk neonates.

Differential effects of phorbol ester on growth and protein kinase C isoenzyme regulation in human hepatoma Hep3B cells

PMA has both mitogenic and antiproliferative effects on human hepatoma Hep3B cells. In response to low PMA concentration (10 nM), Hep3B cells displayed an increasing proliferation potentiation. At high PMA concentration (1 microM) Hep3B cells exhibited modest cytostatic effects. Determinations of protein kinase C (PKC) activity in PMA-treated cells revealed that alterations in PKC activity are associated with proliferative capacity. The decrease in PKC activity mediated by a high dose of PMA was accompanied by cell growth inhibition. Increases in PKC activity mediated by a low dose of PMA were consistent with proliferation stimulation. Immunoblot analysis showed that there are at least six PKC isoenzymes: alpha, delta, epsilon, mu, zeta and iota/lambda, constitutively expressed in Hep3B cells. Cellular fractionation and immunocytochemical staining results demonstrated that both 10 nM and 1 microM PMA treatments induced a marked translocation of PKC-alpha from cytosol to membrane or nuclear fraction within 5-30 min. At the same time PKC-delta and epsilon were translocated from the membrane to nuclear fraction. In addition, prolonged treatment with 1 microM PMA, but not with 10 nM PMA, selectively mediated the down-regulation of these three PKC isoenzymes. The distinct effects of different concentrations of PMA on cell proliferation and PKC-alpha, delta and epsilon isoenzyme modulation support the involvement of these three PKC isotypes in the mechanism of action of Hep3B cells in cell growth events.

Torsion of a malignant undescended testis

Cryptorchid testis have a greater risk of malignant change than do normally descended testis. The undescended testis would also be susceptible to torsion by the mechanism of increase in testicular size. A 36-year-old man of torsion of malignant undescended testis is presented. He was diagnosed as having incarcerated inguinal hernia on his first visit to general surgeon due to acute left lower abdominal pain. At laparotomy, a 7.5 x 5.5 x 3.0 cm3, greyish tan color mass was found. The pathological diagnosis is choricarcinoma and teratoma, mixed germ cell tumor. We would emphasise that in any patient presenting with acute abdominal symptoms and an absent scrotal testis, the possibility of a complication of torsion of undescended testis should be considered.

Verifying complete obliteration of carotid artery-cavernous sinus fistula: role of color Doppler ultrasonography

The purpose of this study was to evaluate the role of color Doppler ultrasonography in verifying obliteration of carotid artery-cavernous sinus fistula before and after therapeutic embolization or gamma knife radiosurgery. Before treatment, carotid artery-cavernous sinus fistula showed the following data on color Doppler ultrasonography: (1) increased blood flow in the common carotid artery (220 to 1264 ml/min with mean+/-SD of 728+/-378 ml/min); internal carotid artery (435 to 1097 ml/min with mean+/-SD of 834+/-216 ml/min) in fistulas of the direct type; and external carotid artery (85 to 257 ml/min with mean+/-SD of 170+/-75 ml/min) in fistulas of the indirect type in comparison to the contralateral side; (2) reverse pulsatile flow or spiculated wave form with turbulent flow in the engorged superior ophthalmic vein on the lesion side in all patients. All of the above abnormal hemodynamic changes became normal in six patients immediately after first embolization, in two patients with balloon embolization combined with subsequent direct embolization by direct puncture through the superior orbital fissure or internal carotid artery embolization, and in five patients after gamma knife radiosurgery at 4, 4, 8, 9, and 9 months, respectively. Color Doppler ultrasonography might be a good modality in long-term follow-up of carotid artery-cavernous sinus fistula after gamma knife radiosurgery and embolization.

Retrobulbar haemodynamic changes studied by colour Doppler imaging in glaucoma

PURPOSE

To determine the effect of spontaneously elevated intraocular pressure (IOP) on the ocular circulation, and evaluate the result of IOP-lowering procedures in terms of haemodynamics.

METHODS

Colour Doppler imaging (CDI) was employed to determine the peak systolic velocity (PSV), end-diastolic velocity (EDV) and time average maximal velocity (TAMV), as well as the Pourcelot ratio (PR) and pulsatility index (PI), of the central retinal artery (CRA), posterior ciliary arteries (PCA) and ophthalmic artery. Various CDI parameters of the eyes with elevated IOP were compared with those of the clinically healthy fellow eyes and the control eyes, separately. Also, data from CDI of glaucoma eyes obtained during the period of elevated IOP and then following IOP-lowering procedures were compared, deliberately avoiding the influence of glaucoma medications.

RESULTS

Eyes (n = 12) with elevated IOP showed significantly decreased flow velocities of the CRA and significantly increased PR and PI of the nasal and temporal PCA, compared with the fellow and control eyes, respectively. Following IOP-lowering procedures, the PR and PI of the nasal PCA decreased significantly.

CONCLUSION

Spontaneously elevated IOP may induce haemodynamic changes in the CRA and PCA, but no significant change is identified in the ophthalmic artery. Flow velocities tend to decrease while the resistance indices tend to increase with elevated IOP. Such haemodynamic changes may reverse following normalisation of IOP.

Successful resection of sigmoid colon cancer in a patient with factor XI deficiency

A 42-year-old-women with sigmoid colon adenocarcinoma was found to have isolated prolonged activated partial thromboplastin time (aPTT 102.5 s, normal range 24-36 s) preoperatively. Her medical history included an episode of prolonged postdelivery uterine bleeding 16 years previously. A mixed aPTT test showed immediate correction of the prolonged aPTT, indicating a coagulation factor deficiency in the intrinsic pathway. Factor assays showed factor XI was below 1% of average normal value whereas factor VIII, IX and XII activities were normal. Family screening revealed one sister among the three siblings also had isolated prolonged aPTT. The patient was transfused with four units (5mL/kg) of fresh frozen plasma the day before surgery, then with two units during surgery. The operation was uneventful with no bleeding problems. The patient recovered smoothly and is currently undergoing adjuvant chemotherapy. This is the first formal report of a patient with factor XI deficiency undergoing major surgery in Taiwan. Careful monitoring of aPTT, with fresh frozen plasma transfusion, when needed, may safely overcome bleeding problems during surgery.

Frequent allelic loss on chromosomes 4q and 16q associated with human hepatocellular carcinoma in Taiwan

To define the critical region of liver-specific tumor suppressor genes in human hepatocellular carcinoma (HCC), we analyzed 30 cases of hepatocellular carcinoma using nine 4q and six 16q microsatellite polymorphic DNA markers. We observed one major common deleted region which was flanked by D4S175-D4S1625 and there may be two tumor suppressor genes on chromosome 16q associated with HCC. An extensive study of allelotyping of human HCC was therefore carried out in the candidate region on arms of chromosome 4q with additional tumor tissues and more informative microsatellite DNA markers. These data imply that at least one putative tumor suppressor gene is located in the human chromosome 4q26-q27 region and provides very useful information for further construction of a long-range physical restriction map and thereafter cloning of the putative tumor suppressor gene.

Radiologic and pathologic correlation of adenomyomatosis of the gallbladder

BACKGROUND

To demonstrate the radiologic-pathologic correlation of adenomyomatosis of gallbladder (GBA) and emphasize the role of high-resolution real-time ultrasound (RTUS) in the diagnosis of GBA.

METHODS

Ten (four male and six female, mean age = 49 years) patients with proven GBA (three diffuse, three segmental, and four fundal) diagnosed by histopathology or confirmed by oral cholecystography (OCG) were reviewed. Radiologic studies included OCG (n = 8), RTUS (n = 8), and computed tomography (CT; n = 4). Six patients subsequently underwent cholecystectomy.

RESULTS

Histopathologic correlation between pathologic specimens and OCG, RTUS, and CT was possible in six patients. The diagnostic criteria with ultrasound included numerous tiny intramural cysts containing echogenic foci with reverberation artifacts and associated segmental or diffuse gallbladder wall thickening. OCG with fatty meal demonstrated intramural diverticula. Localized fundal GBA was better visualized on RTUS and CT scan than on OCG.

CONCLUSION

Accurate diagnosis of GBA may be made by either OCG or high-resolution RTUS preoperatively. CT scan may used as an alternative method to help make the diagnosis in equivocal cases.

Triangular fibrocartilage of wrist: presentation on high resolution ultrasonography

This study consisted of two parts. Part I is for detection of the normal triangular fibrocartilage by high resolution ultrasonography and Part II is a preliminary study to evaluate high resolution ultrasonography in the diagnosis of tears of the triangular fibrocartilage. Normally, the triangular fibrocartilage was seen in all cases in Part I as an inverse triangular structure of homogeneous hyperechogenicity on transverse and oblique sagittal scans at the level of the distal radioulnar joint. At its waist it measured from 2.3 to 4.2 mm (mean, 3.0 +/- 0.5 mm) on oblique sagittal scan and from 2.5 to 3.7 mm (mean, 3.2 +/- 0.4 mm) on transverse scan. Under normal conditions, the triangular fibrocartilage is thicker than 2.5 mm on both transverse and oblique sagittal sections with a confidence level of 95%. In Part II, eight of the 47 wrists were found to be hypoechoic in the triangular fibrocartilage region, which proved to be tears by arthrography. Six cases showed a homogeneous hyperchoic triangular fibrocartilage measuring from 1.8 to 2.8 mm (mean, 2.3 +/- 0.5 mm) in transverse section and from 0 to 2.2 mm (mean 1.2 +/- 1.1 mm) in oblique sagittal section; five of these proved to be tears by arthrography. In contrast, 33 wrists had a homogeneous hyperechoic triangular fibrocartilage measuring from 2.5 to 4 mm (mean, 3.1 +/- 0.4 mm) and 2.5 to 4.2 mm (mean, 3.1 +/- 0.6 mm) on transverse and oblique sagittal sections, respectively; 27 proved to be normal triangular fibrocartilage by arthrography. The sensitivity, specificity, positive predictive value, negative predictive value, and accuracy were 68.4%, 96.4%, 92.9%, 81.8%, and 85.1%, respectively. HRUS can display the normal triangular fibrocartilage as a homogeneous hyperechoic and inverted triangular structure. The torn triangular fibrocartilage appears as a hypoechoic region or as thinning (< 2.5 mm) of the hyperechoic structure on either transverse or oblique sagittal section. HRUS has an acceptable accuracy in the diagnosis of triangular fibrocartilage tear.

The correlation between ultrasound-detected renal parenchymal thickness and isotope-detected individual renal function

Ultrasound has been used as a convenient examination method to obtain an estimate of the kidney size and parenchymal thickness. The aim of this study was to determine the relationship between the renal parenchymal thickness and individual renal function. Renal ultrasonography to determine parenchymal thickness and 99mTc-DTPA renal scan to detect individual renal function were carried out on 30 patients. The statistic analysis showed poor correlation between these two factors. The correlation coefficients is 0.1 only. However, the correlation coefficients of the difference of bilateral renal parenchymal thickness and the difference of bilateral renal function in the same patient is much higher (r = 0.67). So, it is unreliable to predict the random single renal function based on parenchymal thickness only. However, in the same patient, it is sometimes worthwhile to differentiate bilateral renal function based on the difference of renal parenchymal thickness between the two kidneys.

Migration of a central venous catheter into pulmonary vein complicated with lung edema in a premature infant

In this paper, we present a preterm infant with acute focal lung edema due to central venous catheter migration into the right pulmonary vein. The substances aspirated from the endotracheal tube contained the parenteral nutrition fluid. Thus, parenteral nutrition fluid extravasation into the lung or a vasculopulmonary fistula was suspected. The course of complication was smooth after the catheter was withdrawn into the right atrium. This unusual presentation during TPN hyperalimentation was described in order to prevent a potentially dangerous event.

Percutaneous drainage in the treatment of emphysematous pyelonephritis: 10-year experience

PURPOSE

We investigated the effect of percutaneous drainage for the treatment of emphysematous pyelonephritis.

MATERIALS AND METHODS

A retrospective analysis was done of 25 patients with emphysematous pyelonephritis who were treated initially with computerized tomography (CT) guided percutaneous drainage during a 10-year period. The patients were concomitantly treated with antibiotics, fluids, and correcting blood glucose and/or ureteral obstruction. We also compared our results of percutaneous drainage to CT findings.

RESULTS

CT identified 12 patients with emphysematous pyelonephritis who had gas with little fluid and 13 who had gas with renal or perirenal fluid collections. In 20 of 25 patients (80%) antibiotic therapy combined with percutaneous drainage constituted the only treatment required. Three patients (12%) whose clinical status improved after percutaneous drainage subsequently underwent elective nephrectomy without further complications. Two patients (8%) died of multiple organ failure. There was no correlation between the gas patterns of emphysematous pyelonephritis and initial success with the antibiotics and percutaneous drainage. There were no recurrences and no complications during a followup of 1 to 10 years (mean 5). Mean duration of treatment was 5.54 weeks (range 1 to 12.6).

CONCLUSIONS

CT is an efficient imaging method for diagnosis, guiding the drainage procedures and monitoring response to percutaneous drainage of emphysematous pyelonephritis. Antibiotic therapy combined with CT guided percutaneous drainage of emphysematous pyelonephritis is an acceptable alternative to antibiotic therapy with surgical intervention.

Intermediate filaments and cytoplasmic networking: new connections and more functions

Recent research highlights the roles of cytoskeletal intermediate filaments (IFs) and their interactions with both the cell surface and other cytoskeletal systems in maintaining cellular integrity and the mechanical properties of cytoplasm. This has been demonstrated by analyses of mutations in IF-associated proteins (IFAPs) that are involved in connecting IFs to cell surface junctions. New data also point to the role of IFAPs as molecular 'nuts and bolts' in the construction of an integrated cytoplasmic architecture. This is highlighted by the initial descriptions of a family of multifunctional molecules that are capable of bridging IFs to other cytoskeletal elements. These findings, together with the development of specific peptide inhibitors capable of disassembling IF networks in vivo, are paving the way to the identification of new cellular functions for IFs and IFAPs.

Breast mass due to alveolar soft part sarcoma of the pectoris major muscle

We present a case of alveolar soft part sarcoma (ASPS) of the pectoris major muscle in a 20-year-old female. She felt a mass in her right side breast for 7 years. The lesion was almost the same size with occasional throbbing pain and tenderness. Fine needle aspiration of the tumor was performed in the OPD and suspicious abnormal cells were reported. Ultrasound (US) examination of the breast revealed a large heterogeneously hypoechoic lesion contiguous to the pectoris major muscle. Profound color flow signals were evident in both central and peripheral regions of the mass. Spectral Doppler US showed high flow velocity in the tumor vessels with resistivity index of 0.73. Surgical intervention was performed and the histological examination yielded a diagnosis of ASPS.

Sonographic signs of complete rotator cuff tears

BACKGROUND

To evaluate the usefulness of high resolution ultrasound (HRUS) in the examination of complete rotator cuff tear (RCT).

METHODS

A prospective study of 157 patients with sonographic examination of shoulder was performed. All of them complained of chronic shoulder pain and were referred by clinician for suspicion of RCT. Their age ranged from 30 to 76 years. The ultrasonic scanners we used were Acuson 128 XP 10 with 7MHz linear transducer, or Diasonics VST master series using 10MHz linear transducer. Examination positions included external rotation of shoulder for scanning biceps tendon and subscapularis tendon, and internal rotation for supraspinatus tendon and lateral scan of infraspinatus tendon and teres minor tendon. Sonographic criteria of complete RCT included 1. complete absence of rotator cuff (RC); 2. focal thinning of RC; 3. focal hypoechoic cleft of RC; 4. focal depression of RC; and 5. heterogeneous hypoechoic RC with subdeltoid bursa fluid. Arthrography was performed after sonography examination on the same day.

RESULTS

Among 49 complete RCTs diagnosed by sonography, 46 were proved to be complete RCT by arthrography; only 3 were false positive. In 108 patients with normal rotator cuff diagnosed by sonography, 104 had compatible results with arthrography; only 4 patients turned out to be complete RCT. The sensitivity, specificity, positive predictive values, negative predictive values and accuracy were 92%, 97.2%, 93.9%, 96.3% and 95.5%, respectively.

CONCLUSIONS

HRUS can directly demonstrate the morphological changes of RC. It has a high sensitivity and specificity in the diagnosis of complete RCT, and can be used as a firstline screening modality for complete RCT in patients with chronic shoulder pain.

Neighborhood Effects in Bird Distributions, Navarre, Spain

This study examines the role of neighborhood effects in the spatial distributions of selected bird species in Navarre, Spain. We employed a geographic information system (GIS) to organize the data on bird distributions and relevant environmental variables and to analyze their spatial patterns. Three bird species were selected for analysis: the European honey-buzzard (Pernis apivorus), the Eurasian hobby (Falco subbuteo), and the European pied flycatcher (Ficedula hypoleuca). Selected environmental variables of the study area were digitized to create a comprehensive data base and logistic regression models were used to evaluate the significance of each variable in the spatial distribution. The spatial patterns of bird distributions were used to extract topological relationships and to identify neighborhood effects. Although all the selected species illustrate a pattern of positive spatial autocorrelation in their distributions, the significance of neighborhood effects varies from species to species. Among the selected species, neighborhood effects are most evident in the distribution of the European pied flycatcher and are significant for the Eurasian hobby. The distribution of the European honey-buzzard is not much affected by neighborhood effects. The results suggest that examination of neighborhood effects is a prerequisite for modeling bird distributions.KEY WORDS: neighborhood effects, spatial autocorrelation, logistic regression, bird distributions.

The function of intermediate filaments in cell shape and cytoskeletal integrity

This study describes the development and use of a specific method for disassembling intermediate filament (IF) networks in living cells. It takes advantage of the disruptive effects of mimetic peptides derived from the amino acid sequence of the helix initiation 1A domain of IF protein chains. The results demonstrate that at 1:1 molar ratios, these peptides disassemble vimentin IF into small oligomeric complexes and monomers within 30 min at room temperature in vitro. Upon microinjection into cultured fibroblasts, these same peptides induce the rapid disassembly of IF networks. The disassembly process is accompanied by a dramatic alteration in cell shape and the destabilization of microtubule and actin-stress fiber networks. These changes in cell shape and IF assembly states are reversible. The results are discussed with respect to the roles of IF in cell shape and the maintenance of the integrity and mechanical properties of the cytoplasm, as well as the stability of the other major cytoskeletal systems.

The relative roles of specific N- and C-terminal phosphorylation sites in the disassembly of intermediate filament in mitotic BHK-21 cells

Previously we identified p34cdc2 as one of two protein kinases mediating the hyperphosphorylation and disassembly of vimentin in mitotic BHK-21 cells. In this paper, we identify the second kinase as a 37 kDa protein. This p37 protein kinase phosphorylates vimentin on two adjacent residues (thr-457 and ser-458) which are located in the C-terminal non-alpha-helical domain. Contrary to the p34cdc2 mediated N-terminal phosphorylation (at ser-55) which can disassemble vimentin intermediate filaments (IF) in vitro, p37 protein kinase phosphorylates vimentin-IF without obviously affecting its structure in vitro. We have further examined the in vivo role(s) of vimentin phosphorylation in the disassembly of the IF network in mitotic BHK cells by transient transfection assays. In untransfected BHK cells, the interphase vimentin IF networks are disassembled into non-filamentous aggregates when cells enter mitosis. Transfection of cells with vimentin cDNA lacking the p34cdc2 phosphorylation site (ser55:ala) effectively prevents mitotic cells from disassembling their IF. In contrast, apparently normal disassembly takes place in cells transfected with cDNA containing mutated p37 kinase phosphorylation sites (thr457:ala/ser458:ala). Transfection of cells with vimentin cDNAs lacking both the N- and C-terminal phosphorylation sites yields a phenotype indistinguishable from that obtained with the single N-terminal mutant. Taken together, our results demonstrate that the site-specific phosphorylation of the N-terminal domain, but not the C-terminal domain of vimentin plays an important role in determining the state of IF polymerization and supramolecular organization in mitotic cells.