PubMed Health⌕ Search

Biomedical subjects

J R Wagner

Publications and source records attributed to J R Wagner.

At least 55 records · Page 3Linked to original sources

Management of gunshot injuries to the penis and anterior urethra.

OBJECTIVE: To verify the appropriate methods of diagnosis and treatment of gunshot injuries to the penis and anterior urethra. DESIGN: Retrospective study. MATERIALS AND METHODS: Fourteen patients presented over 5 years with gunshot wounds to the male genitalia with injuries involving the penis and or the anterior urethra. All patients underwent a full physical examination and retrograde urethrogram to fully stage suspected injuries. RESULTS: Of the nine patients sustaining penile wounds, four were superficial, requiring only debridement, and five involved the corpus cavernosum, necessitating formal repair. Physical findings of an expanding hematoma, a palpable corporeal defect, and excessive bleeding via the wounds were indicative of cavernosal injury and warranted a penile exploration. All patients were potent in follow-up, although two patients with extensive injuries did complain of curvatures. Retrograde urethrograms noted anterior urethral injuries in eight patients, three of whom also had sustained cavernosal injuries. Five were repaired primarily, and three were treated by urinary diversion via a suprapubic tube. Three patients developed urethral strictures: one in the primary repair group and two in the diversion group. CONCLUSIONS: The preferred method of handling low-velocity gunshot wounds to the penis and anterior urethral includes debridement of superficial wounds, repair of cavernosal defects, and primary repair of urethral injuries wherein tissue loss is not extensive to result in high-potency rates and lower rates of urethral stricture disease.

Adolescent↗

Cost-effective health information systems: user-driven internal development at the University of Iowa.

GOALS: The Information Network For Online Retrieval & Medical Management (INFORMM), health information system (HIS) for the University of Iowa Hospitals and Clinics (UIHC), was analyzed with regard to development of a Computer-Based Patient Record (CBPR) in a cost-effective manner. The analysis: i) profiles INFORMM system functionality; ii) displays INFORMM use and satisfaction among physicians, nurses, and other hospital employees; iii) characterizes dynamics affecting INFORMM growth; and iv) evaluates the cost of a system of internal-development of software. DATA SOURCES: INFORMM utilization for 1989, 1994, and 1995; service requests from users for the years 1985, 1990, and 1994; 1994 MECON-PEERx data; gap analysis user survey conducted by an independent consulting firm. MAIN RESULTS: 1) Physician use has been dominated by a single function: retrieval of laboratory results. 2) Nurse use of the system was more diverse. A recent surge of nurse and physician use resulted from the introduction of online documentation of nursing care. 3) Overall use has been predominantly by non-clinician users, no one function dominating their pattern of use. 4) User service requests were predominantly from the non-clinician group of users. Requests from non-physician groups have been coordinated by a limited number of representatives of those groups, unlike requests from physicians. 5) The UIHC HIS ranked high in user satisfaction. 6) The overall cost of the UIHC HIS system is relatively low as a percentage of the gross operating budget or as a ratio to the volume of patient activities in this medical center. CONCLUSIONS: Internal development of INFORMM has been a cost-effective solution to the information demands of nursing staff and other users. INFORMM system composition reflects the quantity and organization of user requests. Satisfying the needs of physicians requires a change in the manner in which physician needs are assessed.

Attitude to Computers↗

DNA strand scission and base release photosensitized by metallo-phthalocyanines.

Photoirradiation of aqueous solutions of DNA in the presence of Al- or Zn-tetrasulphonated phthalocyanines (AIPcS4 and ZnPcS4) causes formation of strand breaks and liberation of nucleobases. The effect of added D2O, which enhances singlet oxygen (1O2) lifetime, radical scavengers including alcohols and the spin-trap DMPO, as well as superoxide dismutase, indicates that both singlet oxygen (1O2) and free radicals contribute to the production of strand breaks. However, in the case of base release, only free radicals, such as the hydroxyl radical (.OH), appear to be involved in the degradation process. Detection of the characteristic free-radical oxidation products of deoxyribose provides evidence that .OH are involved in the photosensitized DNA damage. EPR and spin trapping data suggest that superoxide (O2.-) is the most likely precursor of .OH and a Fenton-type mechanism is proposed for their formation.

DNA↗

The oxidation of blood plasma and low density lipoprotein components by chemically generated singlet oxygen.

Human blood plasma and freshly isolated LDL were exposed to singlet oxygen (1O2) by thermal decomposition of synthetic endoperoxides. Exposure of blood plasma to 20 mM water-soluble 1O2 generator resulted in the depletion of ascorbate (100%), urate (75%), ubiquinol-10 (65%), protein thiols (50%), and bilirubin (25%), whereas under these conditions the levels of alpha-tocopherol, beta-carotene, and lycopene remained unchanged. The following rates of depletion were obtained by kinetic analysis (moles depleted per 100 mol of 1O2 consumed): protein thiols (5), urate (5), ascorbate (4), bilirubin (1), and ubiquinol-10 (0.008). In contrast, the rates of depletion using the lipid-soluble 1O2 generator were faster for bilirubin (13-fold), protein thiols (9-fold), ubiquinol-10 (8-fold), and ascorbate (5-fold), and slower for urate (2-fold). The formation of lipid hydroperoxides, including mostly cholesteryl linoleate hydroperoxide, was observed in 1O2-treated plasma (0.007-0.009 mol/100 mol 1O2) and LDL solutions (0.086 mol/100 mol 1O2). Based on competition kinetics, we estimate that 98% of 1O2 generated in the aqueous phase of plasma is quenched by components in this phase, mostly by plasma protein (63%; 6% by protein thiols), urate (9%; 5% by chemical quenching), and bilirubin (5%; 1% by chemical quenching). Ascorbate and ubiquinol-10 do not contribute to 1O2 quenching in plasma, and their oxidation is probably mediated secondary species. The remaining 1O2 generated in plasma (2%) diffuses into lipoprotein leading to the formation of lipid hydroperoxides with an efficiency of about 100-fold greater than that compared to aqueous generated 1O2. The principal 1O2 quenchers in LDL include apoB (42%), lycopene and beta-carotene (40%), and alpha-tocopherol (17%). The importance of carotenoids in the quenching of 1O2 in lipoprotein suggest that the beneficial effects of these compounds in health may in part be due to the elimination of this species in biology and medicine.

Adult↗

Non-Hodgkin's lymphoma can mimic renal adenocarcinoma with inferior vena caval involvement.

Genitourinary involvement in both Hodgkin's and non-Hodgkin's lymphomas is common and can be confused with other benign and malignant urologic conditions. While lymphoma commonly produces vascular and ureteral encasement, intraluminal vascular involvement is rare. Indeed, there are no previous reports of renal lymphoma with tumor thrombus extending into both the renal vein and inferior vena cava. We describe the first reported case of lymphoma mimicking a Stage IIIA renal adenocarcinoma with tumor thrombus in the renal vein and the inferior vena cava. Renal lymphoma should be considered in the differential diagnosis even when tumor thrombus is present in the renal vein or vena cava.

Adenocarcinoma↗

Management of implant-related problems and infections.

Problem-solving and treating various types of infections that can cause alveolar bone loss or inferior alveolar nerve dehiscences by failed implants or teeth are discussed. The reasons why implants fail from either surgical or prosthetic errors are reviewed. Treatment remedies which have solved numerous implant-related problems are offered. The eclectic, multi-modal implant surgical and prosthetic abilities of the clinician necessary today for successfully treating patients presenting with troubled or infected implants are reviewed.

Blade Implantation↗

Endogenous oxidative damage of deoxycytidine in DNA.

Three major oxidation products of 2'-deoxycytidine (dC)--5-hydroxy-2'-deoxycytidine (oh5dC), 5-hydroxy-2'-deoxyuridine (oh5dU), and 5,6-dihydroxy-5,6-dihydro-2'-deoxyuridine (dUg)--were analyzed from enzymatically hydrolyzed DNA with reversed-phase high-performance liquid chromatography coupled to electrochemical detection. oh5dC and oh5dU can be detected with high sensitivity (50 fmol) and selectivity (0-0.2 V) from hydrolyzed DNA. dUg is not electrochemically active but can be measured by dehydrating it into oh5dU. The quantities of oh5dC, dUg, and oh5dU in untreated commercial-grade calf thymus DNA are 10, 10, and 0.75 fmol/micrograms of DNA, respectively. These levels increased substantially when calf thymus DNA was exposed to ionizing radiation, H2O2 alone, H2O2 and combinations of Fe3+ or Cu2+ and ascorbate, near-UV light (365 nm), near-UV light in the presence of menadione, and OsO4, indicating that oh5dC, oh5dU, and dUg are major oxidative DNA damage products. The steady-state levels of these products were determined from freshly extracted rat tissues and ranged from less than 0.5 fmol/micrograms of DNA for oh5dU to about 10 fmol/micrograms of DNA for oh5dC and dUg in liver and kidney and 22 fmol/micrograms of DNA for oh5dC in brain. The levels of oxo8dG were also determined and in general were somewhat lower than the levels of oh5dC. These findings reinforce the link between DNA damage induced by oxidative metabolism and spontaneous mutagenesis leading to cancer and aging.

Animals↗

Portable ultrasonography in critical care.

A 2-year retrospective analysis of portable ultrasound examinations in the intensive care unit was conducted to evaluate the indications and efficacy of portable sonography. A total of 86 examinations were performed on 79 patients. Of these, 22 per cent of the examinations supported the suspected diagnosis and contributed to treatment. Seventy per cent of the examinations excluded the suspected diagnosis. There was a 9 per cent incidence that yielded unsuspected information that contributed to treatment. Only 8 per cent of the examinations were misleading or proven false. The authors found that with an overall sensitivity of 79 per cent and specificity of 97 per cent, portable ultrasonography is a valuable, relatively inexpensive test in the critical care setting.

Abscess↗

Sinus lift grafts and endosseous implants. Treatment of the atrophic posterior maxilla.

Patients from multicenters were treated with sinus lift graft operations and placement of implants. Surgical procedures healed uneventfully with minimum pain, swelling, or morbidity. Grafts healed with few complications or failures. Implants placed into the grafts support prosthetic reconstruction and are predictable over time. The question of what graft material to use is discussed. Grafts of non-resorbable HA (Interpore 200), bovine cortical HA (Bio-Oss), resorbable HA (OsteoGen), and freeze-dried demineralized bone powder and granules are presented. Results of biopsy, histometry, backscattered electron microscopy, cell labeling, and special stain suggest consistent bone growth into a variety of graft materials. In the authors' opinion investigation must continue to 1. Determine the healing time for different graft materials. At present, anecdotal evidence suggests that sinus grafts of autogenous bone heal for 4 to 6 months; freeze-dried demineralized bone heals for 12 to 16 months; and alloplastic materials with freeze-dried demineralized bone heal for 9 to 11 months. 2. Evaluate histologic evidence of bone growth into different bone replacement graft materials. 3. Evaluate the long-term follow-up and success of implants placed within sinus grafts. 4. Determine the remodeling potential of different hard tissue graft materials under implant functional loads.

Atrophy↗

Quinone sensitized electron transfer photooxidation of nucleic acids: chemistry of thymine and thymidine radical cations in aqueous solution.

The 2-methyl-1,4-naphthoquinone (MQ) sensitized photooxidation of nucleic acid derivatives has been studied by laser flash photolysis and steady state methods. Thymine and thymidine, as well as other DNA model compounds, quench triplet MQ by electron transfer to give MQ radical anions and pyrimidine or purine radical cations. Although the pyrimidine radical cations cannot be directly observed by flash photolysis, the addition of N,N,N',N'-tetramethyl-1,4-phenylenediamine (TMPD) results in the formation of the TMPD radical cation via scavenging of the pyrimidine radical cation. The photooxidation products for thymine and thymidine are shown to result from subsequent chemical reactions of the radical cations in oxygenated aqueous solution. The quantum yield for substrate loss at limiting substrate concentrations is 0.38 for thymine and 0.66 for thymidine. The chemistry of the radical cations involves hydration by water leading to C(6)-OH adduct radicals of the pyrimidine and deprotonation from the N(1) position in thymine and the C(5) methyl group for thymidine. Superoxide ions produced via quenching of the quinone radical anion with oxygen appear to be involved in the formation of thymine and thymidine hydroperoxides and in the reaction with N(1)-thyminyl radicals to regenerate thymine. The effects of pH were examined in the range pH 5-8 in both the presence and absence of superoxide dismutase. Initial C(6)-OH thymine adducts are suggested to dehydrate to give N(1)-thyminyl radicals.

Cations↗

A new osteoconductive resorbable hydroxylapatite graft material that restores bony defects with viable bone.

The reconstruction and repair of a large mandibular bony defect following an extraction was accomplished using resorbable hydroxylapatite OsteoGen (HA RESORB). The complete repair of the defect and alveolar architecture with dense regenerated bone was achieved prior to the surgical insertion of an endosseous titanium implant. The implant was used for additional support for a long span fixed prosthesis. Histological studies of harvested bone core specimens of the resorbable hydroxylapatite grafts at four months and 14 months are compared and discussed in this report.

Aged↗