Copper uptake is required for pyrrolidine dithiocarbamate-mediated oxidation and protein level increase of p53 in cells

The p53 tumour-suppressor protein is a transcription factor that activates the expression of genes involved in cell cycle arrest, apoptosis and DNA repair. The p53 protein is vulnerable to oxidation at cysteine thiol groups. The metal-chelating dithiocarbamates, pyrrolidine dithiocarbamate (PDTC), diethyldithiocarbamate, ethylene(bis)dithiocarbamate and H(2)O(2) were tested for their oxidative effects on p53 in cultured human breast cancer cells. Only PDTC oxidized p53, although all oxidants tested increased the p53 level. Inductively coupled plasma MS analysis indicated that the addition of 60 microM PDTC increased the cellular copper concentration by 4-fold, which was the highest level of copper accumulated amongst all the oxidants tested. Bathocuproinedisulphonic acid, a membrane-impermeable Cu(I) chelator inhibited the PDTC-mediated copper accumulation. Bathocuproinedisulphonic acid as well as the hydroxyl radical scavenger d-mannitol inhibited the PDTC-dependent increase in p53 protein and oxidation. Our results show that a low level of copper accumulation in the range of 25-40 microg/g of cellular protein increases the steady-state levels of p53. At copper accumulation levels higher than 60 microg/g of cellular protein, p53 is oxidized. These results suggest that p53 is vulnerable to free radical-mediated oxidation at cysteine residues.

The correlation between pretreatment serum hormone levels and treatment outcome for patients with prostatic cancer and bony metastasis

OBJECTIVE

To evaluate whether pretreatment serum hormone levels are a prognostic factor for prostatic cancer with bony metastasis under hormonal treatment.

PATIENTS AND METHODS

Between 1980 and 1994, 96 patients with prostate cancer and bony metastasis were included for an evaluation by a retrospective review of their charts. All 96 had received hormonal treatment after a diagnosis of metastatic prostatic carcinoma. Serum testosterone, luteinizing hormone (LH), follicle-stimulating hormone (FSH) and prolactin were assessed before treatment. The patients were divided into two groups according to their response during the follow-up. Group 1 (good response) had no change or resolution of metastatic lesion(s) on the bone scan and a declining prostate-specific antigen (PSA) level. Group 2 had increased PSA or progression of metastatic lesion(s) on the bone scan. Tumours were graded as low (2-4), intermediate (5-7) and high (8-10) using the Gleason score.

RESULTS

There were 43 patients in group 1 and 53 in group 2; the overall mean (sd) age was 72.5 (6.8) years and the follow-up 29.5 (0.5) months. The respective mean (sd) levels of testosterone, LH, FSH and prolactin before treatment were 4.6 (1.6) ng/mL, 20.2 (13.3) mIU/mL, 19.6 (18.6) mIU/mL and 20.7 (12.1) ng/mL in group 1, and 2.6 (1.0) ng/mL, 27.3 (11.0) mIU/mL, 27.1 (9.8) mIU/mL and 41.3 (28.4) ng/mL in group 2. The level of testosterone was significantly higher in group 1 than in group 2, while LH, FSH and prolactin were significantly lower in group 1 than in group 2. When stratified by tumour grade, patients in group 1 still had significantly higher pretreatment testosterone and lower LH, FSH and prolactin than those in group 2.

CONCLUSION

Higher testosterone and lower LH, FSH and prolactin levels were good prognostic factors for patients with metastatic prostatic cancer under hormonal treatment, irrespective of tumour grading.

Kuntz's fiber: the scapegoat of surgical failure in sympathetic surgery

Resection of Kuntz's fiber is considered a guarantee to treat Hyperhidrosis in sympathetic surgery. The incidence of Kuntz's fiber is about 60.0% in clinical studies while the surgical failure rate is about 1.5% when Kuntz's fiber is preserved on Endoscopic Thoracic Sympathetic Block by clamping, which is performed by clamping the upper and lower end of ganglion. We found that supererogatory resection of Kuntz's fiber is inessential; clamping of upper and lower ends of the ganglia should be a complete procedure in sympathetic surgery. Kuntz's fiber plays only anatomic, and no clinical role in surgical failure of sympathetic surgery.

Endoscopic t4-sympathetic block by clamping (ESB4) in treatment of hyperhidrosis palmaris et axillaris--experiences of 165 cases

Prevention of postoperative complications becomes relatively important when surgical procedures are easy to learn and perform. Endoscopic Thoracic Sympathetic Surgery (ETS), which is now more accessible to surgeons after the 2nd International Symposium of Thoracic Sympathicotomy, would be the typical examples in surgery. Reflex sweating is one of the famous and annoying complications that surgeons endeavor to avoid but in vain in ETS. Incidentally, we found that preservation of sympathetic tone to the head is the main influential factor in avoiding reflex sweating in ETS; and with the lower sympathetic ganglion blocked, the more sympathetic tone to the head is preserved. T4-sympathetic block is an ideal procedure that can treat palmar and/or axillary hyperhidrosis and preserve most of sympathetic tone to head. We used T4-sympathetic block by clamping (ESB4) in treatment of 165 cases of Hyperhidrosis et axillaris and attained excellent operative results without reflex sweating from August 1, 2000 to February 28, 2001. We concluded, ESB4 is the method that can treat hand and axillary hyperhidrosis without inducing reflex sweating.

Species distribution of polymeric aluminium-ferrum--timed complexation colorimetric analysis method of Al-Fe-ferron

The effects of the colorimetric buffer solutions were investigated while the two colorimetric reactions of Al-ferron complex and Fe-ferron complex occurred individually, and the effects of the testing wavelength and the pH of the solutions were also investigated. A timed complexation colorimetric analysis method of Al-Fe-ferron in view of the total concentration of (Al + Fe) was then established to determine the species distribution of polymeric Al-Fe. The testing wavelength was recommended at 362 nm and the testing pH value was 5. With a comparison of the ratios of nAl/nFe, the standard adsorption curves of the polymeric Al-Fe solutions were derived from the experimental results. Furthermore, the solutions' composition were various in both the molar nAl/nFe ratios, i.e. 0/0, 5/5, 9/1 and 0/10, and the concentrations associated with the total [Al + Fe] which ranged from 10(-5) to 10(-4) mol/L.

Significance of benign endometrial cells in Pap smears from postmenopausal women

OBJECTIVE

To assess the significance of benign exfoliated endometrial epithelial or stromal cells on cervicovaginal Pap smears obtained from postmenopausal women not receiving exogenous hormones.

STUDY DESIGN

A computerized search of the cytology database at two institutions was performed for a five-year period, and all cervical cytology cases from postmenopausal patients diagnosed with benign endometrial cells were identified. Those cases with histologic follow-up within 12 months of the original cytologic evaluation were selected for analysis, and their cytology and surgical pathology slides were reviewed.

RESULTS

A total of 227 postmenopausal women with benign endometrial cells were identified. Of the 61 patients with histologic follow-up, 25 (41%) had significant endometrial diseases, including hyperplasia without atypia (11), atypical endometrial hyperplasia (5), well-differentiated adenocarcinoma (8) and high grade serous carcinoma (1). Benign diagnoses, including atrophy (15), weakly proliferative endometrium (9) and proliferative endometrium (6), were noted in 30 patients (49%). Endometrial polyp was identified in three patients (5%). There were three cases of nondiagnostic histologic specimens that lacked endometrial tissue (5%). Two of nine women (22%) with proven carcinoma were asymptomatic.

CONCLUSION

The diagnosis of endometrial cells, cytologically benign, in a postmenopausal woman not receiving hormone on Pap smears is associated with a significant number of cases of endometrial hyperplasia, atypical hyperplasia and carcinoma.

The role of nitric oxide in development of topographic precision in the retinotectal projection of chick

The axonal projection from the retina to the tectum exhibits a precise topographic order in the mature chick such that neighboring ganglion cells send axons to neighboring termination zones in the contralateral tectum. The initial pattern formed during development is much less organized and is refined to the adult pattern during a discrete period of development. Refinement includes elimination of radically aberrant projections, such as those from the temporal side of the retina to posterior regions of the tectum, as well as a more subtle improvement in the topographic precision of the projection. The enzyme that synthesizes nitric oxide is expressed at high levels in the tectum during the developmental period in which the topography improves. Pharmacological blockade of nitric oxide synthesis during this period prevented elimination of topographically inappropriate retinotectal projections in a dose-dependent manner. This effect could not be duplicated by treatment of embryos with a vasoconstrictor, indicating that vascular changes were not a factor. These results show that nitric oxide is involved in refinement of the topography of the retinotectal projection as well as in other aspects of refinement of this projection in developing chick.

Antimite activity of essential oils and their constituents from Taiwania cryptomerioides

Antimite activity of essential oils and their components obtained from Taiwania cryptomerioides Hayata heartwood against Dermatophagoides pteronyssinus (Trouessart) and Dermatophagoides farinae Hughes was investigated in this study. Results from antimite tests demonstrated that the essential oil extracted from T. cryptomerioides heartwood had miticidal activity against D. pteronyssinus and D. farinae with a mortality of 67.0 and 36.7% at the dosage of 12.6 microg/cm2 after 48 h. Alpha-cadinol possessed the strongest antimite activity compared with other components of the T. cryptomeioides heartwood essential oil. The rectified mortalities of D. pteronyssinus and D. farinae were 100% for alpha-cadinol at the dosage of 6.3 microg/cm2. The order of antimite activity of four dominant constituents was alpha-cadinol > T-muurolol > ferruginol > T-cadinol. Paired Student's t-tests showed that there were significant differences between the rectified mortality of alpha-cadinol, T-muurolol, ferruginol and that of T-cadinol at the dosage of 6.3 microg/cm2 after 48 h.

Antinociceptive effect of a genomic herpes simplex virus-based vector expressing human proenkephalin in rat dorsal root ganglion

Endogenous opiate peptides acting pre- and post-synaptically in the dorsal horn of spinal cord inhibit transmission of nociceptive stimuli. We transfected neurons of the dorsal root ganglion in vivo by footpad inoculation with 30 microl (3 x 10(7) p.f.u.) of a replication-incompetent (ICP4-deleted) herpes simplex virus (HSV) vector with a cassette containing a portion of the human proenkephalin gene coding for 5 met- and 1 leu-enkephalin molecules under the control of the human cytomegalovirus immediate-early promoter (HCMV IEp) inserted in the HSV thymidine kinase (tk) locus. Vector-directed expression of enkephalin produced a significant antinociceptive effect measured by the formalin footpad test, that was most prominent in the delayed ("tonic") phase 20-70 min after the administration of formalin. The magnitude of the antinociceptive effect diminished over 4 weeks after transduction, but reinoculation of the vector reestablished the analgesic effect, without evidence for the development of tolerance. The antinociceptive effect was blocked completely by intrathecal naltrexone. These results suggest that gene therapy with an enkephalin-producing herpes-based vector may prove useful in the treatment of pain.

Video-assisted thoracoscopic sympathetic ramicotomy for hyperhidrosis--a way to reduce the complications

Endoscopic resectional surgery of sympathetic nerves is now the most acceptable method to treat palmar hyperhidrosis, though the resection of the sympathetic trunk and ganglia can result in the irreversible compensatory hyperhidrosis. The ideal way to treat the palmar hyperhidrosis, without the undesirable complication of the compensatory hyperhidrosis, is still pending. We adapt endoscopic cutting of the second and third sympathetic rami without injury to the sympathetic ganglia and trunk, and find that it is a good way to reduce the complications. Most importantly, it has a cure rate comparable with the conventional technique. The longer operation time and the higher operation risk are the drawbacks.

Video-assisted thoracoscopic management of mediastinal tumors

BACKGROUND

Many successful attempts at removing benign mediastinal tumors with the video-assisted thoracoscopic technique have been reported, but no formal report has been published regarding malignant mediastinal tumors treated with this technique. We report our preliminary experience with video-assisted thoracoscopic removal of mediastinal tumors, benign or malignant.

METHODS

Seven patients with mediastinal tumors treated with video-assisted thoracoscopic surgery were reviewed from January 1999 to April 2000. Their tumor pathologies included benign or malignant thymoma, neurilemmoma, and teratoma.

RESULTS

The mean operation time was 240 minutes. The mean blood loss was 173 mL. The mean insertion time of chest tubes was 3 days. The mean admission time was 6 days. No deaths occurred during the study. Morbidity occurred in 2 patients. No tumor recurrence has been seen during the mean follow-up of 7 months.

CONCLUSIONS

The short-term results support the feasibility of VATS in managing technically resectable mediastinal tumors. Yet the long-term prognosis for the malignant lesions is deferred and needs further study.

Normal development of the ipsilateral retinocollicular pathway and its disruption in double endothelial and neuronal nitric oxide synthase gene knockout mice

The development of the ipsilateral retinocollicular pathway involves activity-dependent refinement in which misdirected axons retract to form a precise retinotopic map in adults. This refinement is altered by disruption of genes for the endothelial and neuronal isoforms of nitric oxide synthase (e,nNOS), but the extent of disruption during early development is not known. Therefore, we studied the refinement of this pathway in normal C57/BL6 and e,nNOS double knockouts from P4 to P21 and in adults. Anterograde tracers were injected into one eye to localize the ipsilateral retinal projection (IRP) within the superior colliculus (SC). At P4, the IRP in normal mice was distributed throughout the dorsoventral extent of the superficial gray layer (SGL) across most of the rostrocaudal axis of SC. Between P4 and P9, the pathway retracted to the rostromedial SC, and retracted further between P15 and P21, such that multiple patches of label were seen only in the rostral 200-300 microm. Refinement also began to occur between P4 and P9 in e,nNOS double knockout mice, but labeling was more extensive in P9, P15, and P21 knockout animals. This delay in refinement was confirmed quantitatively at P15 where differences in the area occupied by the pathway were statistically significant. The refinement process is therefore in progress in both normal and e,nNOS knockout mice before eye opening but is significantly delayed in the double knockouts. The IRP in normal mice is also more exuberant at early ages, and the process of refinement more protracted than has been previously reported, suggesting that there is a prolonged critical period of synaptic plasticity.

p53 protein oxidation in cultured cells in response to pyrrolidine dithiocarbamate: a novel method for relating the amount of p53 oxidation in vivo to the regulation of p53-responsive genes

A novel method was developed to determine the oxidation status of proteins in cultured cells. Methoxy-polyethylene glycol-maleimide MW 2000 (MAL-PEG) was used to covalently tag p53 protein that was oxidized at cysteine residues in cultured cells. Treatment of MCF7 breast cancer cells with pyrrolidine dithiocarbamate (PDTC), a metal chelator, resulted in a minimum of 25% oxidation of p53. The oxidized p53 had an average of one cysteine residue oxidized per p53 protein molecule. The effect of PDTC treatment on downstream components of the p53 signal-transduction pathway was tested. PDTC treatment prevented actinomycin D-mediated up-regulation of two p53 effector gene products, murine double minute clone 2 oncoprotein and p21(WAF1/CIP1) (where WAF1 corresponds to wild-type p53-activated fragment 1 and CIP1 corresponds to cyclin-dependent kinase-interacting protein 1). Actinomycin D treatment led to accumulation of p53 protein in the nucleus. However, when cells were simultaneously treated with PDTC and actinomycin D, p53 accumulated in both the nucleus and the cytoplasm. The data indicate that an average of one cysteine residue per p53 protein molecule is highly sensitive to oxidation and that p53 can be efficiently oxidized by PDTC in cultured cells. PDTC-mediated oxidation of p53 correlates with altered p53 subcellular localization and reduced activation of p53 downstream effector genes. The novel method for detecting protein oxidation detailed in the present study may be used to determine the oxidation status of specific proteins in cells.

Endometrial brush biopsy (Tao brush). Histologic diagnosis of 200 cases with complementary cytology: an accurate sampling technique for the detection of endometrial abnormalities

We examined 200 cases of endometrial brush biopsy (EBB) using the Tao brush and correlated findings with histologic findings from subsequent dilatation and curettage (D&C) or hysterectomy specimens. Diagnosis by EBB relied mainly on histologic evaluation of H&E-stained tissue sections and was complemented by additional cytologic smear examination. EBB correctly detected the following cases: endometrioid adenocarcinoma, 3; complex hyperplasia with atypia, 1; simple hyperplasia without atypia (SH), 2; and benign endometrium, 177. In 3 cases the diagnosis of atrophic endometrium was made by EBB; corresponding D&C specimens were nondiagnostic. Five cases of SH were interpreted by EBB as proliferative endometrium, and 13 endometrial polyps were not identified by EBB. Nine samples were nondiagnostic. Sensitivity and specificity were 100% for detecting atypical hyperplasia and carcinoma. However, it was difficult for EBB to distinguish SH from disordered proliferative endometrium or to diagnose endometrial polyps. We found that diagnosis by EBB is reproducible; a second pathologist blinded to histologic follow-up correctly identified all adenocarcinoma/atypical hyperplasia cases. EBB is an accurate, safe, and easy procedure that is well tolerated by patients and should be considered in the initial evaluation of high-risk outpatients.

Integrated control of the dengue vector Aedes aegypti in Liu-Chiu village, Ping-Tung County, Taiwan

Because of an inadequate supply of potable water, villagers of Small Liu-Chiu Isle, Ping-Tung County, Taiwan, store water in containers supporting a large population of Aedes aegypti. In 1989-96, integrated control measures against Ae. aegypti were implemented on the basis of community participation. These measures included release of mosquito larvivorous fish in the drinking water storage facilities, application of larvicides to the water storage facilities in vegetable gardens, removal of discarded and unused containers and tires, improvement of household water storage facilities, and increase of potable water supply. Before implementation of the integrated control measures in 1988, 74% of the water-containing vessels were water storage facilities, and 24% of those were infested by Ae. aegypti. In 1989, the Breteau index for the entire island, indicating the average distribution density for larval Ae. aegypti, was 53.9, as compared to an index of 1.2 in 1996. In 4 villages located at the southwest and middle of the island, Ae. aegypti nearly became extinct because of the enthusiastic participation of the community. Before the implementation of integrated control, Ae. aegypti was the dominant species in containers both inside and outside the household, but after the integrated control, Aedes albopictus became predominant outside.

Refinement of the ipsilateral retinocollicular projection is disrupted in double endothelial and neuronal nitric oxide synthase gene knockout mice

Development of retinal connections to the superior colliculus (SC) requires an activity dependent refinement process in which axons gradually become restricted to appropriate retinotopic locations. Nitric oxide has been implicated in this process. We tested this possibility by studying the refinement of the ipsilateral retinocollicular projections (IRP) in normal C57-BL/6 mice and in double knockout mice in which the genes for the edothelial and neuronal isoforms of nitric oxide synthase (e, nNOS) were disrupted. Mice aged between P19 and adulthood were perfused 44-48 h after anterograde injections of WGA-HRP into one eye in order to measure the distribution of the labeled IRP. In normal mice, segregation of the IRP was complete at P21, with the ipsilateral projection restricted to the rostro-medial SC. By contrast, the ipsilateral projection was spread over much more of the SC in double e, nNOS knockouts at P21 with patches of label distributed across the entire medio-lateral axis of the rostral 700 microm. Although the distribution of the ipsilateral projection became more restricted in knockout animals at later ages, it was still more extensive than that of normal mice of the same age at P28 and P42. In the adult, the distribution of axons was similar in both normal and double knockout animals. These results show that refinement of the IRP is delayed when expression of eNOS and nNOS is disrupted, presumably to axons with uncorrelated activity because nitric oxide serves as a repellant molecule during normal development.

The declining significance of race among American men during the latter half of the twentieth century

The extent to which racial minority groups face discrimination in the labor market is the subject of considerable debate. Using William J. Wilson's thesis of the declining significance of race as our theoretical context, we provide further empirical evidence about labor market discrimination by investigating wages among African American, American Indian, Chinese American, Hispanic white, Japanese American, and non-Hispanic white men. We find, during the period before the civil rights movement, that a substantively significant wage disadvantage is evident for these minority groups with controls for observed labor force characteristics. In recent data, these net disadvantages are reduced substantially for each of these groups except Hispanics. With the exception of Hispanics, the results support Wilson's thesis.

MDM2--master regulator of the p53 tumor suppressor protein

MDM2 is an oncogene that mainly functions to modulate p53 tumor suppressor activity. In normal cells the MDM2 protein binds to the p53 protein and maintains p53 at low levels by increasing its susceptibility to proteolysis by the 26S proteosome. Immediately after the application of cellular stress, the ability of MDM2 to bind to p53 is blocked or altered in a fashion that prevents MDM2-mediated degradation. As a result, p53 levels rise, causing cell cycle arrest or apoptosis. In this review, we present evidence for the existence of three highly conserved regions (CRs) shared by MDM2 proteins and MDMX proteins of different species. These highly conserved regions encompass residues 42-94 (CR1), 301-329 (CR2), and 444-483 (CR3) on human MDM2. These three domains are respectively important for binding p53, for binding the retinoblastoma protein, and for transferring ubiquitin to p53. This review discusses the major milestones uncovered in MDM2 research during the past 12 years and potential uses of this knowledge in the fight against cancer.

A wavelet-frame based image force model for active contouring algorithms

This paper proposes a directional image force (DIF) for active contouring. DIF is the inner product of the zero crossing strength (ZCS) of wavelet frame coefficients, and the normal of a snake, by representing strength and orientation of edges at multiple resolution levels. DIF markedly improves the immunity of snakes to noise and convexity.

TP53 tumor suppressor protein in normal human fibroblasts does not respond to 837 MHz microwave exposure

The TP53 tumor suppressor protein (formerly known as p53) responds to a wide variety of environmental insults. To evaluate the safety of cellular telephones, TP53 responses in human fibroblast cells were studied after exposure to 837 MHz microwaves. Cells were exposed in a temperature-controlled transverse electromagnetic (TEM) chamber to a specific absorption rate (SAR) of 0.9 or 9.0 W/kg at 837 MHz continuous-wave (CW) microwave irradiation for 2 h. The TP53 protein levels were measured by Western blot at 2, 8, 24 and 48 h after treatment. The TP53 protein levels in microwave-treated cells, sham-treated cells, and untreated cells remained unchanged relative to each other at all times tested (Fisher test and Student-Newman-Keuls test, P > 0.05). No morphological alterations were observed in microwave-treated cells compared to sham-treated cells. We conclude that TP53 protein expression levels in cultured human fibroblast cells do not change significantly during a 48-h period after exposure to 837 MHz continuous microwaves for 2 h at SAR levels of 0.9 or 9.0 W/kg.

Fine-needle aspiration cytology of well-differentiated inflammatory liposarcoma: a case report with histologic follow-up

Inflammatory liposarcoma is an unusual variant of well-differentiated liposarcoma. We report on the fine-needle aspiration (FNA) cytology findings of a retroperitoneal well-differentiated inflammatory liposarcoma from a 63-yr-old white female. The smears showed numerous dispersed inflammatory cells, with the majority being reactive lymphoid cells and plasma cells. There were scattered, large, atypical cells containing multiple or hyperlobated nuclei with coarse chromatin and abundant ill-defined cytoplasm. The large atypical cells, as well as the inflammatory cells, were also found within the fibrous tissue fragments. The follow-up surgical resection of the tumor demonstrated a well-differentiated inflammatory liposarcoma with coexistent dedifferentiated areas and lipoma-like, well-differentiated liposarcoma. With the appropriate anatomic and radiographic settings, the FNA cytology findings of abundant, reactive inflammatory cells and scattered, large, atypical tumor cells that are CD15-, CD30-, and cytokeratin-negative are highly suggestive of a well-differentiated inflammatory liposarcoma.

The role of nitric oxide in development of the patch-cluster system and retinocollicular pathways in the rodent superior colliculus

Nitric oxide (NO) has been implicated as a retrograde signal in the process of refining axonal pathways during brain development. To determine some of the factors involved in this process, we have used two model pathway systems in the rat and mouse superior colliculus (SC). The first, the patch-cluster system, consists of clusters of neurons in the intermediate gray layer (igl) which transiently express NO during development and which receive input from a cholinergic pathway from the parabrachial brainstem as well as from other pathways containing different transmitters. The second system, the retinocollicular pathway, consists of glutamatergic fibers that project to the superficial gray layer. We have used both nitric oxide synthase inhibition (nw-nitro-L-arginine, NoArg) and single (nNOS) and double (nNOS and eNOS) gene knockout mice to examine the effect that reduction in NOS has upon the development of these two systems. The onset of NOS expression in rat, as revealed by nicotinamide adenine dinucleotide phosphate diaphorase (NADPH-d) labeling, occurred in igl cells as early as postnatal day P5, with clusters being well-established by P14. Cholinergic fibers were first visible at P10 and formed obvious patches and tiers by P14. Intraperitoneal injections of NoArg from P1-P22 had no effect upon the development of these cholinergic patches. The pathway also developed normally in both single and double-knockout mice. In contrast, the ipsilateral retinocollicular pathway was altered in the double, but not in the single knockout mouse. This pathway is exuberant during the first week of life, being distributed across much of the mediolateral axis of the rostral SC. By P8-P15, this pathway has retracted to the most mediorostral SC. This refinement was delayed substantially in the double NOS gene knockout mouse. Ipsilateral fibers were found within 3-5 separate medio-lateral patches within the rostral 600 microns of SC at P15, and patches of abnormal size and extent were also seen at P18. We conclude from these results that NO plays a role in pathway development in the rodent SC, but only in glutamatergic pathways and only when both endothelial and neuronal forms of NOS have been deleted. The mechanism of this effect must involve pathway elimination in situations where there is non-correlated electrical activity. It is likely that NO promotes fiber retraction rather than fiber stabilization in these developing nerve fibers.

NMDA receptor-mediated refinement of a transient retinotectal projection during development requires nitric oxide

A transient ipsilateral retinotectal projection is normally eliminated during embryonic development of the chick visual system. Administration of the NMDA receptor antagonist 5-methyl-10, 11-dihydro-5H-dibenzo[a,d]cyclohepten-5,10-imine (MK-801) during the developmental period in which this projection normally disappears prevented its complete elimination. Previous studies showed that tectal cells express nitric oxide synthase during development, and blocking synthesis of nitric oxide also prevented elimination of the ipsilateral retinotectal projection. The effect of NMDA receptor blockade on nitric oxide synthase activity in tectal cells was assessed biochemically in chick embryos. Increasing concentrations of MK-801 resulted in a dose-dependent decrease in nitric oxide synthase activity. This result suggests that NMDA receptor activation can regulate nitric oxide synthase activity in the tectum. The degree of rescue of the ipsilateral retinotectal projection was compared in embryos treated either with MK-801 or with an inhibitor of nitric oxide synthesis, Nomega-nitro-L-arginine (L-NoArg). At comparable levels of inhibition of nitric oxide synthesis, no significant difference was observed in the degree of rescue mediated by NMDA receptor blockade or nitric oxide synthesis blockade. These results suggest that NMDA receptor-mediated elimination of the ipsilateral retinotectal projection is completely mediated via nitric oxide.

Complicated urinary tract infection: analysis of 179 patients

BACKGROUND

The aim of our study was to investigate the incidence, bacteriology, management and outcome of complicated urinary tract infections (UTIs) at the Veterans General Hospital-Taipei.

METHODS

Between June, 1993, and July, 1994, medical records of 2,566 patients admitted to the Division of Urology, Veterans General Hospital-Taipei, were retrospectively reviewed. Of these patient, 1,322 had a diagnosis of benign prostatic hyperplasia (BPH), 607 were admitted for renal stones, 496 for ureteral stones, 75 for transitional cell carcinoma (TCC) of the urinary bladder, 47 for renal tumors and 19 for TCC of the ureter. Among all patients studied, 179 (6.98%) acquired a complicated UTI. Of these, 81 were admitted for BPH, 46 for renal stones, 42 for ureteral stones, five for TCC of the urinary bladder, three for renal tumors and two for TCC of the ureter.

RESULTS

Of the 179 patients with complicated UTIs, 155 were men and 24 were women. The urine culture positive rate was 76.0% (136/179) and the most common bacteria were Escherichia coli, Proteus mirabilis and Pseudomonas aeruginosa. The principle mode of treatment included parenteral antibiotics and urinary diversion (percutaneous nephrostomy and Foley catheterization), when necessary. The infection control rate for these complicated UTIs was 96.3% for BPH, 95.5% for renal stone, 97.6% for ureteral stone, 80% for TCC of the urinary bladder, 100% for renal tumor and 100% for TCC of the ureter. Mortality due to complicated UTI was 3.9% (7/179).

CONCLUSIONS

We concluded that the prognosis of complicated UTI is good if diagnosis and appropriate treatment are given promptly. Early drainage to relieve obstruction and intravenous antibiotics are initially necessary. Surgical intervention is required to resolve functional or structural abnormalities after the UTI has been controlled.