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Over the past decade, there has been a concerted effort to surgically relieve the bladder outlet obstructive symptoms in men with benign pro-static hypertrophy (BPH) by using a laser. Recent improvements in laser technology have led to the development of promising new treatment modalities. The potassium-titanyl-phosphate photoselective laser vaporization of the prostate procedure effectively vaporizes the obstructing prostatic adenoma in a 1-day surgery procedure. Current results show that this procedure provides a feasible option for men seeking long-term relief of bladder outlet obstructive symptoms due to BPH. [ABSTRACT FROM AUTHOR]

Antibody-mediated receptor activation is successfully used to develop medical treatments. If the activation induces a pathological response, such antibodies are also excellent tools for defining molecular mechanisms of target receptor malfunction and designing rescue therapies. Prominent examples are naturally occurring autoantibodies inducing the severe blistering disease pemphigus vulgaris (PV). In the great majority of patients, the antibodies bind to the adhesion receptor desmoglein 3 (Dsg3) and interfere with cell signaling to provoke severe blistering in the mucous membranes and/or skin. The identification of a comprehensive causative signaling network downstream of antibody-targeted Dsg3 receptors (e.g., shown by pharmacological activators or inhibitors) is currently being discussed as a basis to develop urgently needed first-line treatments for PV patients. Although polyclonal PV IgG antibodies have been used as proof of principle for pathological signal activation, monospecific anti-Dsg3 antibodies are necessary and have been developed to identify pathological Dsg3 receptor-mediated signal transduction. The experimental monospecific PV antibody AK23, produced from hybridoma cells, was extensively tested in our laboratory in both in vitro and in vivo models for PV and proved to recapitulate the clinicopathological features of PV when generated using the standardized production and purification protocols described herein. © 2024 The Author(s). Current Protocols published by Wiley Periodicals LLC. Basic Protocol 1: Bovine IgG stripping from FBS and quality control Basic Protocol 2: AK23 hybridoma expansion and IgG production Basic Protocol 3: AK23 IgG purification Basic Protocol 4: AK23 IgG quality control Support Protocol 1: Detection of endotoxin levels Support Protocol 2: Detection and removal of mycoplasma., (© 2024 The Author(s). Current Protocols published by Wiley Periodicals LLC.)

Background/objective: To compare the prehospital treatment modalities and intervention regimens for major trauma patients with comparable injury patterns between Austria and Germany., Patients and Methods: This analysis is based on data retrieved from the TraumaRegister DGU®. Data included severely injured trauma patients with an injury severity score (ISS) ≥ 16, an age ≥ 16 years, and who were primarily admitted to an Austrian (n = 4186) or German (n = 41,484) level I trauma center (TC) from 2008 to 2017. Investigated endpoints included prehospital times and interventions performed until final hospital admission., Results: The cumulative time for transportation from the site of the accident to the hospital did not significantly differ between the countries (62 min in Austria, 65 min in Germany). Overall, 53% of all trauma patients in Austria were transported to the hospital with a helicopter compared to 37% in Germany (p < 0.001). The rate of intubation was 48% in both countries, the number of chest tubes placed (5.7% Germany, 4.9% Austria), and the frequency of administered catecholamines (13.4% Germany, 12.3% Austria) were comparable (Φ = 0.00). Hemodynamic instability (systolic blood pressure, BP ≤ 90 mmHg) upon arrival in the TC was higher in Austria (20.6% vs. 14.7% in Germany; p < 0.001). A median of 500 mL of fluid was administered in Austria, whereas in Germany 1000 mL was infused (p < 0.001). Patient demographics did not reveal a relationship (Φ = 0.00) between both countries, and the majority of patients sustained a blunt trauma (96%). The observed ASA score of 3-4 was 16.8% in Germany versus 11.9% in Austria., Conclusion: Significantly more helicopter EMS transportations (HEMS) were carried out in Austria. The authors suggest implementing international guidelines to explicitly use the HEMS system for trauma patients only a) for the rescue/care of people who have had an accident or are in life-threatening situations, b) for the transport of emergency patients with ISS > 16, c) for transportation of rescue or recovery personnel to hard to reach regions or, d) for the transport of medicinal products, especially blood products, organ transplants or medical devices., (© 2023. The Author(s).)

Neighborhoods, as built and social environments, have significant implications for mental health. Children raised in high-poverty neighborhoods, who are disproportionately Black, Indigenous, and people of color, have a greater risk of adverse life outcomes. Neighborhood gentrification is also salient when examining mental health outcomes as neighborhood economic contexts shift around a child. This review scopes, describes, synthesizes, and critiques the existing literature on the relationship between neighborhood poverty/gentrification and mood disorder symptoms among children ages 3-17 in the United States (U.S.). Given the history of structural racism in the creation of U.S. neighborhoods, inclusion criteria required that study samples be racially diverse. Following Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines for scoping reviews, seven databases and grey literature were searched; 17 studies were included (total n = 122,089). Fourteen studies found significant associations between neighborhood poverty/gentrification and child depression. Three longitudinal studies found significant results suggesting that childhood neighborhood poverty/gentrification may have a lagged effect, with depression emerging later in life. Neighborhood poverty and gentrification require further examination as social determinants of mental health. Researchers should examine neighborhood poverty and gentrification as social determinants of mental health. Policies that reduce neighborhood economic disparities are needed across the U.S.

Evidence of fluctuations in transport have long been predicted in 3 He. They are expected to contribute only within 100μK of T c and play a vital role in the theoretical modeling of ordering; they encode details about the Fermi liquid parameters, pairing symmetry, and scattering phase shifts. It is expected that they will be of crucial importance for transport probes of the topologically nontrivial features of superfluid 3 He under strong confinement. Here we characterize the temperature and pressure dependence of the fluctuation signature, by monitoring the quality factor of a quartz tuning fork oscillator. We have observed a fluctuation-driven reduction in the viscosity of bulk 3 He, finding data collapse consistent with the predicted theoretical behavior., (© 2023. Springer Nature Limited.)

The aim of this current study was to establish a metaphyseal femoral non-union model in osteoporotic rats by comparing a power tool versus a manual tool for fracture creation. Twelve adult female Sprague Dawley rats were ovariectomized (OVX) and received a special diet for 6 weeks. Biweekly pQCT measurements confirmed a significant reduction in the cancellous and total bone mineral density in OVX rats compared to control (CTRL) animals. After 6 weeks, OVX rats underwent surgery creating a distal metaphyseal osteotomy, either using a piezoelectric- (n = 6) or a manual Gigli wire (n = 6) saw. Fractures were stabilized with a Y-shaped mini-locking plate. Within each group, three rats received Alginate directly into the fracture gap. OVX animals gained more weight over 8 weeks compared to CTRL animals. pQCT analysis showed a significant difference in the volumetric cancellous bone mineral density between OVX and CTRL rats. A histological examination of the osteoporotic phenotype was completed. Radiographic evaluation and Masson-Goldner trichrome staining with the piezoelectric saw failed to demonstrate bony bridging or a callus formation. New bone formation and complete healing were seen after 6 weeks in the Gigli group. For the creation of a metaphyseal atrophic non-union in the osteoporotic bone, a piezoelectric saw should be used.

Objectives: We carried out a retrospective cohort study to differentiate geriatric odontoid fractures into stable and unstable and correlated it with fracture fusion rates. Results are based on the literature and on our own experience. The authors propose that the simple Anderson and D'Alonzo classification may not be sufficient for geriatric patients., Methods: There were 89 patients ≥ 65 years who presented at our institution with type II and III odontoid fractures from 2003 until 2017 and were included in this study. Each patient was categorized with CT scans to evaluate the type of fracture, fracture gap (mm), fracture angulation (°), fracture displacement (mm) and direction (ventral, dorsal). Fractures were categorized as stable [SF] or unstable [UF] distinguished by the parameters of its angulation (< / > 11°) and displacement (< / > 5 mm) with a follow-up time of 6 months. SFs were treated with a semi-rigid immobilization for 6 weeks, UFs surgically-preferably with a C1-C2 posterior fusion., Results: The classification into SFs and UFs was significant for its angulation (P = 0.0006) and displacement (P < 0.0001). SF group (n = 57): A primary stable union was observed in 35, a stable non-union in 10, and an unstable non-union in 8 patients of which 4 were treated with a C1/2 fixation. The overall consolidation rate was 79%. UF group (n = 32): A posterior C1-C2 fusion was carried out in 23 patients, a C0 onto C4 stabilization in 7 and an anterior odontoid screw fixation in 2. The union rate was 100%. Twenty-one type II SFs (91%) consolidated with a nonoperative management (P < 0.001). A primary non-union occurred more often in type II than in type III fractures (P = 0.0023). There was no significant difference in the 30-day overall case fatality (P = 0.3786)., Conclusion: To separate dens fractures into SFs and UFs is feasible. For SFs, semi-rigid immobilization provides a high consolidation rate. Stable non-unions are acceptable, and the authors suggest a posterior transarticular C1-C2 fixation as the preferred surgical treatment for UFs., Level of Evidence: Level III., (© 2022. The Author(s).)

We introduce a versatile and practical framework for applying matrix product state techniques to continuous quantum systems. We divide space into multiple segments and generate continuous basis functions for the many-body state in each segment. By combining this mapping with existing numerical density matrix renormalization group routines, we show how one can accurately obtain the ground-state wave function, spatial correlations, and spatial entanglement entropy directly in the continuum. For a prototypical mesoscopic system of strongly interacting bosons we demonstrate faster convergence than standard grid-based discretization. We illustrate the power of our approach by studying a superfluid-insulator transition in an external potential. We outline how one can directly apply or generalize this technique to a wide variety of experimentally relevant problems across condensed matter physics and quantum field theory.

We present a case of a secondary injury to the femoral artery in a geriatric male patient who sustained a pertrochanteric femoral fracture. Six days after closed fracture reduction and intramedullary femoral nailing, the patient presented with persistent hematocrit level drops, femoral swelling and pain. A computed tomography angiography of the femur revealed a perforation of the profunda femoris artery through the dislocated lesser trochanter fragment, and immediate surgical revision was induced. The patient returned to his pre-injury mobilization level without any peripheral vascular or neurological deficiencies. A literature review suggests that the occurrence of vascular damage in proximal femoral fractures is rare but mainly presents in geriatric patients due to atherosclerosis and brittle bone mass.

We analyze an experimentally realizable model of bosons in a zigzag optical lattice, showing that, by rapidly modulating the magnetic field, one can tune interaction parameters and realize an analog of the Haldane phase. We explain how quantum gas microscopy can be used to detect this phase's nonlocal string order and its topological edge states. We model the detection process. We also find that this model can display supersolid correlations, but argue that they only occur at parameter values which would be challenging to realize in an experiment.

A central challenge in modern condensed matter physics is developing the tools for understanding nontrivial yet unordered states of matter. One important idea to emerge in this context is that of a 'pseudogap': the fact that under appropriate circumstances the normal state displays a suppression of the single particle spectral density near the Fermi level, reminiscent of the gaps seen in ordered states of matter. While these concepts arose in a solid state context, they are now being explored in cold gases. This article reviews the current experimental and theoretical understanding of the normal state of strongly interacting Fermi gases, with particular focus on the phenomonology which is traditionally associated with the pseudogap.

We characterize the collective modes of a soliton train in a quasi-one-dimensional Fermi superfluid, using a mean-field formalism. In addition to the expected Goldstone and Higgs modes, we find novel long-lived gapped modes associated with oscillations of the soliton cores. The soliton train has an instability that depends strongly on the interaction strength and the spacing of solitons. It can be stabilized by filling each soliton with an unpaired fermion, thus forming a commensurate Fulde-Ferrell-Larkin-Ovchinnikov (FFLO) phase. We find that such a state is always dynamically stable, which paves the way for realizing long-lived FFLO states in experiments via phase imprinting.

In bulk superfluid 3 He at zero magnetic field, two phases emerge with the B-phase stable everywhere except at high pressures and temperatures, where the A-phase is favoured. Aerogels with nanostructure smaller than the superfluid coherence length are the only means to introduce disorder into the superfluid. Here we use a torsion pendulum to study 3 He confined in an extremely anisotropic, nematically ordered aerogel consisting of ∼10 nm-thick alumina strands, spaced by ∼100 nm, and aligned parallel to the pendulum axis. Kinks in the development of the superfluid fraction (at various pressures) as the temperature is varied correspond to phase transitions. Two such transitions are seen in the superfluid state, and we identify the superfluid phase closest to T c at low pressure as the polar state, a phase that is not seen in bulk 3 He.

We study the vortex structures of a (pseudo)spin-1/2 Fermi gas experiencing a uniform effective magnetic field in an anisotropic trap that interpolates between quasi-one dimensional (1D) and quasi-two dimensional (2D). At a fixed chemical potential, reducing the anisotropy (or equivalently increasing the attractive interactions or increasing the magnetic field) leads to instabilities towards pair density waves and vortex lattices. Reducing the chemical potential stabilizes the system. We calculate the phase diagram and explore the density and pair density. The structures are similar to those predicted for superfluid Bose gases. We further calculate the paired fraction, showing how it depends on the chemical potential and anisotropy.

We study the time scales for adiabaticity of trapped cold bosons subject to a time-varying lattice potential using a dynamic Gutzwiller mean-field theory. We explain apparently contradictory experimental observations by demonstrating a clear separation of time scales for local dynamics (~ ms) and global mass redistribution (~1 s). We provide a simple explanation for the short and fast time scales, finding that while density or energy transport is dominated by low energy phonons, particle-hole excitations set the adiabaticity time for fast ramps. We show how mass transport shuts off within Mott-insulator domains, leading to a chemical potential gradient that fails to equilibrate on experimental time scales.

Superconductivity and magnetism generally do not coexist. Changing the relative number of up and down spin electrons disrupts the basic mechanism of superconductivity, where atoms of opposite momentum and spin form Cooper pairs. Nearly forty years ago Fulde and Ferrell and Larkin and Ovchinnikov (FFLO) proposed an exotic pairing mechanism in which magnetism is accommodated by the formation of pairs with finite momentum. Despite intense theoretical and experimental efforts, however, polarized superconductivity remains largely elusive. Unlike the three-dimensional (3D) case, theories predict that in one dimension (1D) a state with FFLO correlations occupies a major part of the phase diagram. Here we report experimental measurements of density profiles of a two-spin mixture of ultracold (6)Li atoms trapped in an array of 1D tubes (a system analogous to electrons in 1D wires). At finite spin imbalance, the system phase separates with an inverted phase profile, as compared to the 3D case. In 1D, we find a partially polarized core surrounded by wings which, depending on the degree of polarization, are composed of either a completely paired or a fully polarized Fermi gas. Our work paves the way to direct observation and characterization of FFLO pairing.

Objectives: To illustrate the correlations and effects of age, gender and cause of accident on the type of vertebral fracture and fracture distribution, as well as on the likelihood to sustain an associated injury or neurological deficit., Design: Retrospective analysis of 562 patients with a traumatic fracture of the spine. Each patient was analysed by reviewing the medical records, the initial radiographs and CT-scans., Setting: Level 1 trauma centre from 01/1996 to 12/2000., Results: The most common cause of accident was a high-energy fall (39%), followed by traffic accidents (26.5%). While fall related fractures were evenly distributed over the whole spine, traffic accidents induced significantly more fractures of the cervical and thoracic spine. Sixty-five percent of all cervical spine fractures and 80% of the multisegmental injuries were accompanied by an associated injury. The highest incidence of associated injuries was observed in patients with multilevel fractures (96.5%). Patients with a concomitant injury were more likely to sustain a spinal cord lesion. Sixty-three (11.2%) patients exhibited a complete motor and sensory deficit, 76 (13.5%) an incomplete and 423 (75.3%) no neurological deficit. The highest number of complete motor and sensory neurological deficits was found in cervical spine fractures (19.7%). The majority of patients, 308 (54.8%), sustained a compression fracture, 95 (16.9%) a distraction fracture, and 104 (18.5%) patients experienced a rotational fracture., Conclusions: This study demonstrates correlations between the cause of accident, the type of spinal fracture and the fracture distribution. Using the AO classification, the likelihood to sustain either associated and/or spinal cord injuries, is predictable.

We argue that helium film-mediated hydrogen-hydrogen interactions strongly reduce the magnitude of cold collision shifts in spin-polarized hydrogen adsorbed on a helium film. With plausible assumptions about experimental parameters this can explain (i) the 2 orders of magnitude discrepancy between previous theory and recent experiments and (ii) the anomalous dependence of the cold collision frequency shifts on the film's 3He covering. The mediated interaction is attractive, suggesting that in current experiments the gas will become unstable before reaching the Kosterlitz-Thouless transition.

We model the impact of final-state interactions on the radio frequency spectrum of a strongly interacting two-component superfluid Fermi gas. In addition to a broad asymmetric peak coming from the breakup of Cooper pairs, we find that, for appropriate parameters, one can observe a sharp symmetric "bound-bound" spectral line coming from the conversion of Cooper pairs in one channel to pairs or molecules in another.

We calculate the zero-temperature (T=0) phase diagram of a polarized two-component Fermi gas in an array of weakly coupled parallel one-dimensional (1D) "tubes" produced by a two-dimensional optical lattice. Increasing the lattice strength drives a crossover from three-dimensional (3D) to 1D behavior, stabilizing the Fulde-Ferrell-Larkin-Ovchinnikov (FFLO) modulated superfluid phase. We argue that the most promising regime for observing the FFLO phase is in the quasi-1D regime, where the atomic motion is largely 1D but there is weak tunneling in the other directions that stabilizes long-range order. In the FFLO phase, we describe a phase transition where the quasiparticle spectrum changes from gapless near the 3D regime to gapped in quasi-1D.

We study the effects of surface tension between normal and superfluid regions of a trapped Fermi gas at unitarity. We find that surface tension causes notable distortions in the shape of large aspect ratio clouds. Including these distortions in our theories resolves many of the apparent discrepancies among different experiments and between theory and experiments.

Closed-form analytic expressions are derived for the density profile of a harmonically trapped noninteracting Fermi gas in d dimensions. Shell structure effects are included to leading order in 1/N, where N is the number of particles. These corrections to the local density approximation scale as deltan/n approximately N-alpha, where alpha=(1+1/d)/2.

We show that, apart from a difference in scale, all of the surprising recently observed properties of a degenerate Fermi gas near a Feshbach resonance persist in the high temperature Boltzmann regime. In this regime, the Feshbach resonance is unshifted. By sweeping across the resonance, a thermal distribution of bound states (molecules) can be reversibly generated. Throughout this process, the interaction energy is negative and continuous. We also show that this behavior must persist at lower temperatures unless there is a phase transition as the temperature is lowered. We rigorously demonstrate universal behavior near the resonance.

We propose a simple scheme for generating rotating atomic clusters in an optical lattice which produces states with quantum Hall and spin liquid properties. As the rotation frequencies increase, the ground state of a rotating cluster of spin-1 Bose atoms undergoes a sequence of (spin and orbit) transitions, which terminates at an angular momentum L(*) substantially lower than that of the boson Laughlin state. The spin-orbit correlations reflect "fermionization" of bosons facilitated by their spin degrees of freedom. We also show that the density of an expanding group of clusters has a scaling form which reveals the quantum Hall and spin structure of a single cluster.

We consider the condensate wave function of a rapidly rotating two-component Bose gas with an equal number of particles in each component. If the interactions between like and unlike species are very similar (as occurs for two hyperfine states of (87)Rb or (23)Na) we find that the two components contain identical rectangular vortex lattices, where the unit cell has an aspect ratio of sqrt[3], and one lattice is displaced to the center of the unit cell of the other. Our results are based on an exact evaluation of the vortex lattice energy in the large angular momentum (or quantum Hall) regime.

The patient with marked bladder outlet obstructive symptoms who is taking anticoagulant medication presents a challenge to the urologist. This report consists of six such patients requiring full anticoagulation with oral warfarin. All patients were treated with the Surgical Laser Technologies neodymium: YAG contact laser using the sapphire tip, while they were fully anticoagulated. All patients had their catheters removed the morning following surgery, and were discharged that same morning. On follow-up all are voiding with excellent streams and have marked reduction in their bladder outlet obstructive symptoms. Contact laser vaporization of the prostate provides an efficient and cost-effective therapeutic option in the management of these high-risk patients.

Objective: To determine whether early removal of the indwelling Foley catheter after transurethral resection of the prostate (TURP) significantly shortens the hospital stay without causing additional morbidity and thus saves costs., Patients and Methods: For the year commencing 1 July 1991, 119 patients who had undergone TURP had their indwelling catheter removed on the first day after surgery. The results and morbidity of this group of patients were compared with those in 152 patients undergoing TURP during the previous year. The economic consequences of this protocol were calculated using both Medicare and CHAMPUS data., Results: The demographics of the patients in both groups were similar. Post-operative complications occurred in 5% of the study patients and in 6.6% of controls; a transfusion was required in 2.5% and 1.3%, clot retention developed in 1.7% and 3.3% and the hospital stay was reduced from 3.1 to 1.28 days in the study and control patients, respectively. Using Medicare data, the mean cost saving of early catheter removal would be $829 and $1406 for patients aged < 70 and > 70 years, respectively. For CHAMPUS patients, the cost saving would be $1983., Conclusion: Early removal of the catheter after TURP did not increase morbidity and maintained the efficacy of the procedure. If this practice was adopted nationally, the savings resulting from the reduction in hospital stay would be considerable.

The purpose of this study was to evaluate the efficacy of contact laser vaporization of the prostate as an alternative method of performing transurethral prostatectomy. Fifty patients with bladder outlet obstruction underwent contact laser vaporization of the prostate. Preoperative AUA symptom scores were compared with 3-month postoperative AUA symptom scores. Bleeding, catheter time, average length of hospital stay, and hospital cost are compared to the "gold standard" electrocautery TURP. Prostatic vaporization was performed using a contact laser MTRL-6 round probe, 5 mm in diameter, with the SLT neodymium:YAG (Nd:Yag) contact laser set at 50 W. Procedure time was comparable to that for electrocautery TURP. Average AUA symptom scores were reduced from 22.9 (range, 14-30) preoperatively to 2.1 (range, 0-8) postoperatively. All patients had the foley catheter removed within 24 h; no recatheterizations were required. Of all the patients, 96% were discharged within 24 h; two patients (4%) were not discharged within 24 h because of unrelated coexistent medical problems. All patients were allowed to return to full unrestricted activity within 24 h of discharge. Bleeding was minimal in all cases, with no transfusions required, including three patients in the series on anticoagulant therapy. Hospital costs for the procedure compare favorably to electrocautery TURP. Contact laser TURP using the SLT contact Nd:Yag laser relieved the symptoms of an obstructing prostate comparable to electrocautery TURP. However, these results were achieved with a much shorter hospitalization, a quicker return to full activity, and at a comparable cost.

Alternative treatments for benign prostatic hyperplasia are under intense scrutiny. Initial reports on balloon dilation therapy showed success rates of 60% to 90%, although follow-up was brief. We present a prospective non-blinded study assessing the efficacy of an investigational balloon dilatation catheter (105 Fr at 3 atm) as well as the MRI findings preoperatively and postoperatively. Twenty-seven men underwent balloon dilation and have been followed for at least 1 year. Twelve patients (44%) ultimately required definitive transurethral prostatectomy during follow-up. A mild improvement was noted in the symptom score and flow rate in the responder group. Fracture of the anterior commissure was accomplished in only 5 patients (18%) despite diligent efforts. The MRI scans showed no change in the prostate in any patients. Intraoperative transrectal ultrasound scanning suggested that proximal balloon migration can occur. Our experience with this balloon system leads us to recommend that it remain an investigational procedure.

Prostate specific antigen (PSA) has become an important method for early detection of prostate cancer. It has been suggested that prostate specific antigen density (PSAD) may be a more efficient test for early detection than PSA alone. A series of 327 men undergoing prostate biopsy were evaluated by PSA and PSAD. When the receiver operating characteristic curves of both tests were compared, they demonstrated little improvement in the efficiency of detection with the use of PSAD. The five-fold increase in the cost of PSAD over PSA alone does not justify its inclusion in a plan for early detection for carcinoma of the prostate.

A comparative investigation of the substrate requirements for the enzyme 5-aminoimidazole ribonucleotide (AIR) carboxylase from E. coli and G. gallus has been conducted using in vivo and in vitro studies. In Escherichia coli, two enzymes PurK and PurE are required for the transformation of AIR to 4-carboxy-5-aminoimidazole ribonucleotide (CAIR). The Gallus gallus PurCE is a bifunctional enzyme containing AIR carboxylase and 4-[(N-succinylamino)carbonyl]-5-aminoimidazole ribonucleotide (SAICAR) synthetase. The E. coli PurE and the C-terminal domain of the G. gallus PurCE protein maintain a significant degree of amino acid sequence identity and also share CAIR as a product of their enzymatic activities. The substrate requirements of AIR carboxylases from E. coli and G. gallus have been compared by a series of in vitro experiments. The carbamic acid, N5-carboxyaminoimidazole ribonucleotide (N5-CAIR) is a substrate for the E. coli PurE (Mueller et al., 1994) but not for the G. gallus AIR carboxylase. In contrast, AIR and CO2 are substrates for the G. gallus AIR carboxylase. The recognition properties of the two proteins were also compared using inhibition studies with 4-nitro-5- aminoimidazole ribonucleotide (NAIR). NAIR is a tight-binding inhibitor of the G. gallus AIR carboxylase (K(i) = 0.34 nM) but only a steady-state inhibitor (K(i) = 0.5 microM) of the E. coli PurE. These data suggest significant differences in the transition states for the reactions catalyzed by these two evolutionarily related enzymes.(ABSTRACT TRUNCATED AT 250 WORDS)

Conversion of aminoimidazole ribonucleotide (AIR) to 4-carboxyaminoimidazole ribonucleotide (CAIR) in Escherichia coli requires two proteins, PurE and PurK, previously thought to be subunits of a single enzyme, AIR carboxylase. Past studies revealing an ATP requirement for this reaction (Meyer et al., 1992), in conjunction with present studies, reveal that PurE and PurK possess independent catalytic activities. PurK is shown, by NMR spectroscopy, to catalyze the conversion of AIR in the presence of HCO3- and ATP to ADP, P(i), and the carbamate of AIR (designated N5-CAIR). PurE has been shown by NMR spectroscopy and kinetic analysis, to catalyze the reversible conversion of N5-CAIR and CAIR. N5-CAIR has a half-life of 0.9 min at pH 7.8 and 30 degrees C. Thus, two new enzymatic activities and a new intermediate have been discovered in the de novo purine biosynthetic pathway of E. coli.

To determine the incidence of complications associated with contemporary prostate biopsy, a review of 670 men undergoing transrectal prostate biopsy using 18 gauge biopsy needles was conducted. Of the men 580 received 1 to 3 days of ciprofloxacin antibiotic prophylaxis. A total of 16 patients (2.1%) suffered complications of whom 4 (0.6%) required hospitalization. These data demonstrate the low morbidity associated with contemporary transrectal prostate biopsy.

As testicular ultrasound has evolved, nonpalpable masses have been detected for which an evaluation and treatment protocol has not been established. Our experience with nonpalpable testis masses detected only by ultrasound in 5 patients is presented, with all patients found to have nonmalignant lesions. We recommend that such cases with negative serum tumor markers and normal chest radiographs be followed with serial ultrasounds. Benign masses will resolve completely, while stable or enlarging masses can be locally excised and inguinal orchiectomy completed only if cancer is found by frozen section. A modified staging system to follow these patients is proposed to determine these patients' prognoses: Stage Ia for inguinally removed nonpalpable cancers, Stage Ib for excised nonpalpable cancers without orchiectomy (false-negative frozen section), and Stage Ic for inguinally removed palpable cancers.

Radionuclide cystography and renal scintigraphy are the diagnostic procedures of choice in conjunction with ultrasonography in the workup of pediatric urologic or nephrologic patients. Two interesting case reports--a six-month old and a three-month old--are presented.

Bypass of large segments of the small intestine to produce weight loss in morbidly obese human subjects has been associated with increased lipid accumulation in the liver. Congenital and nutritional obese rat models were employed to evaluate hepatic lipid accumulation following bypass of 90% of the small intestine. When small intestinal bypass was performed on nutritionally obese rats ingesting a high-fat diet (17%) supplemented with choline dihydrogen citrate (3,4 g/kg diet), a 59% loss of weight at 1 mo was unassociated with increased hepatic lipid accumulation when compared to sham-operated controls. When small intestinal bypass was performed on a nutritionally obese rat fed a relative choline-methionine-deficient diet following intestinal bypass, marked increases in total hepatic lipid and hepatic triglyceride content were evident when compared to the lipid content in sham-operated controls ingesting a similar choline-deficient diet. Hepatic steatosis following small intestinal bypass could be produced in a rat model only by a deficiency in a required substrate for triglyceride conversion to phospholipid and suggests that similar deficiencies may contribute to the increased hepatic lipid accumulation occurring in human subjects following intestinal bypass.

Exercise-induced hematuria is becoming a common diagnosis for postexercise hematuria. However, a number of genitourinary tract diseases also may cause gross or microscopic hematuria in some physically active patients. Four cases of postexercise hematuria in patients with transitional cell carcinoma of the bladder are presented. The authors recommend urologic evaluation with excretory urography and cystoscopy for all patients with postexercise hematuria.

We report on 2 patients in whom intractable hematuria was caused by carcinoma of the prostate. Since the hematuria failed to respond to conservative measures, intravesical 1 per cent alum irrigation was used. Hematuria resolved in both patients and no toxicity was observed. Intravesical alum irrigation should be considered in any patient with significant hematuria secondary to carcinoma of the prostate in whom conservative therapy has failed.