Modified bar superstructure for an implant-retained orbital prosthesis

The success of a bar superstructure for an orbital prosthesis may be compromised by the placement and angulation of implants. The following technique describes a modification to a bar superstructure that provided the advantages of convenience, security, and consistent positioning even though one implant was lost and the angulation of implants limited accuracy.

Molecular heterogeneity of the type I GABAA/benzodiazepine receptor complex

We have investigated the presence of alpha 1, gamma 2 and beta 2-3 subunits as part of the type I (high affinity for [3H]zolpidem) GABAA/benzodiazepine receptor from rat cerebral cortex. Three subunit specific antibodies have been used (anti-alpha 1, to the C-terminal of rat alpha 1 subunit; anti-gamma 2, to the large intracellular loop of the gamma 2 subunit short form and the monoclonal 62-3G1, specific to beta 2-3 subunits) in immunoprecipitation experiments of the [3H]zolpidem binding activity or the 51,000 Da [3H]Ro 15-4513 photoaffinity labeled peptide (P51). The results indicated that alpha 1 subunit was present in the whole population (90%) of the GABAA/benzodiazepine receptors with high affinity for [3H]zolpidem. We cannot exclude the presence of other alpha subunits co-localized with alpha 1. On the one hand, 70-75% of type I GABAA/benzodiazepine receptor from rat cortex have co-existing alpha 1, beta 2-3 and gamma 2 subunits. We call this type Ia. On the other hand, 20-25% of the type I GABAA/benzodiazepine receptor complex should be constructed by the association of alpha 1 with subunits other than beta 2-3 and gamma 2. We call this type Ib. The identity of these subunits is currently unknown.

Clinical applications of a polyphosphazene-based resilient denture liner

The use of resilient denture liners provides an invaluable modality in removable prosthodontic treatment. Treatment of atrophic mandibles, preoperative and postoperative soft tissue management, and retention of removable prosthesis are a few applications of these materials. This article describes the clinical application of a polyphosphazene-based liner (Novus, Hygenic Corp, Dayton, OH) as a denture liner and retentive material in conventional and implant overdenture rehabilitation.

RadioVisioGraphy of the temporomandibular joint: comparisons with transcranial radiography

RadioVisioGraphy (RVG), a new digital imaging technique, is compared to conventional transcranial radiographic imaging of the temporomandibular joint. The results of this study using fixed human cadaver specimens revealed an excellent correlation between the recorded images and the actual anatomic specimens. Dosimetry, using a beryllium-windowed ionization chamber, showed a 64% dose reduction with charge-coupled device (CCD) when compared to standard film-screen combination.

Isolation and identification of N-terminally extended forms of 5-oxoprolylglutamylprolinamide (Glp-Glu-Pro-NH2), a thyrotropin-releasing-hormone (TRH)-like peptide present in human semen

N-terminally extended forms of 5-oxoprolylglutamylprolinamide (Glp-Glu-Pro-NH2), a thyrotropin-releasing-hormone(TRH)-like peptide associated with the male reproductive system, were isolated from human semen by gel exclusion on Sephadex G50, ion-exchange chromatography on SP-Sephade C25 and QAE-Sephadex A25, and by HPLC. The peptides were located by trypsin-catalysed release of their C-terminal fragments which were detected by RIA with a TRH-specific antibody. A series of overlapping peptides containing 16, 18, 22 and 25 residues was obtained in homogeneous form and their sequences were determined by automatic Edman degradation. The peptides all terminated in -Lys-Gln-Glu-Pro-NH2 and were found to correspond to sequences occurring between residues 350-374 of semenogelin, a protein present in human semen. In semenogelin, however, the Gln-Glu-Pro sequence is followed by tryptophan and not glycine which is normally essential for formation of the C-terminal amide group. Model experiments with the synthetic peptide Glp-Glu-Pro-Trp showed that under a range of experimental conditions the tetrapeptide did not undergo conversion to Glp-Glu-Pro-NH2. This would indicate that the tripeptide and its extended forms are generated from a precursor that is related to semenogelin but in which Trp375 is replaced by glycine.

Role of detrusor instability in primary enuresis

We studied 50 enuretic boys and girls by supine cystometry. Detrusor instability was found in 74 percent of the cases. The mean threshold volume at which detrusor instability was demonstrated was 200 mL. The mean bladder capacity of age-matched nonenuretic children was 325 mL. We consider detrusor instability at this reduced threshold volume to be the main cause of primary enuresis.

One-appointment construction of an immediate transitional complete denture using visible light-cured resin

A technique is described for construction of an immediate transitional complete denture in one appointment using self-curing tooth color and visible light-cured resins. Conventional immediate denture therapy may be too prolonged for medically or physically compromised patients. This alternative treatment reduces laboratory, dentist, and patient time, thereby providing a fast and economical service.

Neurogenic bladder in acquired immune deficiency syndrome (AIDS)

This is the first report of incidence of neurogenic bladder in patients with acquired immune deficiency syndrome (AIDS) and emphasizes that it is a significant cause of various voiding dysfunctions in these patients. Neurologic disease occurs in about one third of patients with AIDS. Both central and peripheral nervous systems may be involved. Urodynamic evaluation is necessary for assessment and management of neurogenic voiding disorders in this group of patients.

Isolation and identification of two neutral thyrotropin releasing hormone-like peptides, pyroglutamylphenylalanineproline amide and pyroglutamylglutamineproline amide, from human seminal fluid

Two tripeptide amides with stuctures similar to thyrotropin releasing hormone were isolated from human seminal fluid and their amino acid sequences determined. The peptides were purified by gel exclusion from Sephadex G50 and were detected by radioimmunoassay with thyrotropin releasing hormone antibody; in addition, N-terminally extended forms were demonstrated by radioimmunoassay after trypsin digestion. Further purification of the tripeptides was by chromatography on SP-Sephadex C25 and by high performance liquid chromatography on C18 Microbondapak using an HCl/acetonitrile gradient. After exclusion from mini-columns of SP-Sephadex C25 and DEAE-Sephadex A25, two neutral peptides were obtained in homogeneous form by high performance liquid chromatography with an HCl/methanol gradient. Amino acid analysis gave the following compositions: Glu, 0.74, Phe, 1.0, Pro, 1.0; and Glu, 1.72, Pro, 1.0. Both peptides possessed a blocked N terminus, but after opening the pyroglutamyl ring the sequences Glu-Phe-Pro and Glu-Glx-Pro were demonstrated. The chromatographic properties of the endogenous peptides were identical to the properties of the corresponding synthetic peptides. The structure of pGlu-Phe-Pro (where p-indicates pyro-) amide was confirmed by fast atom bombardment mass spectrometry. The presence in human semen of three structurally related peptides, pGlu-Phe-Pro amide, pGlu-Gln-Pro amide, and the previously reported pGlu-Glu-Pro amide (Cockle, S. M., Aitken, A., Beg, F., and Smyth, D. G. (1989) J. Biol. Chem. 264, 7788-7791), suggests that this series of peptides may have evolved to fulfil complementary biological roles.

Oral commissure expansion prosthesis

An expansion prosthesis to stretch commissures and fibrotic muscles is often essential for patients recovering from head and neck trauma or burns. The prosthesis is easily made in one appointment using Triad resin and a 7 mm expansion screw. Depending on the frequency of use, varying degrees of opening of the jaws can be obtained. The prosthesis is inexpensive to make and can easily be modified as needed. It is convenient for use because the patient controls the pressure that is applied by the prosthesis.

Post-prostatectomy incontinence. A urodynamic and fluoroscopic point of view

Sixty-three male patients suffering from post-prostatectomy incontinence were studied by urodynamics and fluoroscopy. In almost half the patients (49%) the sole cause of incontinence was detrusor instability. Incontinence due to damage of the sphincter mechanism was present in less than half of the patients (47%). However, almost half of these patients (53%) had concomitant detrusor instability. Only a small number of patients (4%) had incontinence due to other causes. It appears that post-prostatectomy incontinence is not always due to a surgical misadventure. Many older patients may have preexisting neurologic disorders (e.g., Parkinson disease, diabetic autonomic neuropathy, alcoholic neuropathy, and various spinal cord disorders) which can profoundly affect the outcome of prostatic surgery. Detrusor instability should be considered when evaluating post-prostatectomy incontinence.

Hospital and other influences on the uptake and maintenance of breast feeding: the development of infant feeding policy in a district

Hospital practices in the post-natal period are now recognised as one of a wide range of influences affecting the success of breast feeding. A study of 48 non-medical maternity unit staff and 250 recently delivered mothers at a District General Hospital was carried out in order to identify obstacles and sources of support in the establishment and maintenance of breast feeding. This study formed part of an evaluation of local policy development which included the appointment of a Baby Feeding Adviser. Eighty-two percent of mothers (95% confidence interval; 87.0-96.4) began breast feeding, and this fell to 57.4% (50.6-64.2) at 6 weeks. A majority of mothers reported that advice was at least partly conflicting, and of those who began breast feeding 92.7% had used supplements within 2 days. In multivariate analysis, factors significantly associated with a lower rate of initial breast feeding were: non-attendance at antenatal classes, Caucasian ethnicity, social class and religious denomination. Social factors were much less important in the maintenance of breast feeding, but mothers who had undergone Caesarian section were more likely to give up breast feeding by 6 weeks. The reported quality of advice and support from the hospital and community were not associated with the maintenance of breast feeding. Many of the maternity unit midwifery staff reported inadequate time for discussion of feeding with mothers. Although two-thirds of the staff felt that there should be an infant feeding policy or were not sure, most of those favouring a policy felt that it should not actively promote breast feeding. Their main reason for this view was the fear of inducing guilt in bottle-feeding mothers. The social and service-related factors associated with the initiation and maintenance of breast feeding may be useful for targeting additional support for some mothers. The ambivalence and concerns among maternity unit midwifery staff about promoting breast feeding must be addressed if successful policy implementation is to be achieved. Plans for implementing change and evaluation are described.

Neurogenic bladder in neuroleptic malignant syndrome

Urinary retention or incontinence is not an infrequent clinical finding in patients with neuroleptic malignant syndrome. We studied the pathophysiology of this voiding disorder by urodynamic testing. It revealed involuntary bladder contraction and rigidity of external sphincter (dyskinesia). These findings are analogous to those in Parkinson disease patients and support the dopamine deficiency theory as the cause of neuroleptic malignant syndrome.

The bond strength of a visible light-cured reline resin to acrylic resin denture base material

The introduction of Triad visible light-cured denture resin has led to several applications. Among them is direct intraoral relining of complete and partial dentures. This study investigated the bonding characteristics of Triad reline resin to four commonly used heat-cured denture base resins. The shear and tensile bond strengths of Triad resin and four denture base resins were determined and compared with intact tensile strengths. The findings of this study indicate that the bond strength of Triad resin to denture base resin is sufficiently high to suggest its clinical applicability.

Analysis of voiding disorders in patients with cerebrovascular accidents

Urodynamic evaluation was undertaken in 33 patients (15 males and 18 females, age range 48-90 years) with voiding problems following cerebrovascular accidents. In the majority of these patients (26) cystometry revealed involuntary contractions of the bladder. The critical volume for involuntary bladder contractions was approximately 200 mL. The majority of patients with cerebral cortex and/or internal capsule lesions had uninhibited relaxation of the sphincter during involuntary bladder contractions, while all of the patients with lesions only in the basal ganglia or thalamus had normal sphincter function. The remaining 7 patients had poor bladder contractions. Correlation of bladder dysfunction with the area of brain injury was not conclusive, but was suggestive of directions to be taken in future research.

Soft palate obturator prosthesis made with visible light-cured resin

A technique is described using a visible light-cured resin system for the fabrication of a soft palate obturator prosthesis. This method is easy to use and saves time for both the patient and maxillofacial prosthodontist by eliminating some laboratory procedures.

Shoulder preparations for collarless metal ceramic crowns: hand-planning as opposed to rotary instrumentation

This study was undertaken to determine whether hand-planning the gingival facial floor improved the overall fit and marginal adaptation of a collarless metal ceramic crown. An extracted central incisor was prepared conventionally. Separate impressions were made of the tooth with custom trays and poured in stone. Crowns were constructed and cemented with silicone impression material as the luting agent. The silicone film was captured in stone and sectioned. Film thickness was measured at six points on the buccal and lingual surfaces. The tooth was then modified at the gingival floor by hand-planning the margin to a smooth, flat finish, and the above procedures repeated. It was found that the fit of crowns as measured by the cement film thickness was significantly better (p less than 0.05) at the facial margin, facial, lingual incisal, and lingual surfaces for the hand-planned margins.

Urinary incontinence after transurethral resection of prostate in myasthenia gravis patients

An unusually high incidence of urinary incontinence following transurethral resection of the prostate has been reported in patients with myasthenia gravis who were operated on for prostatism. It has been documented that this may be due to the vulnerability of the external sphincter to the electrothermal changes during transurethral resection of the prostate. In the case we studied, neuropathic changes were observed in the external sphincter; thus transvesical prostatectomy was performed instead, and no compromise of continence occurred.

Adhesion characteristics of visible light-cured denture base material bonded to resilient lining materials

This investigation compared the adhesion of resilient lining materials to Triad visible light-cured denture base material. The liners used were Tru-Soft, Molloplast-B, and Esscheem. Cylindrical samples were made from Triad VLC material and were sectioned to produce a flat bonding surface, which was roughened and treated with Triad bonding agent. Resilient liners 3 mm thick were processed according to the manufacturer's recommendations and samples were stored at 37 degrees +/- 1 degree C in distilled water for 48 hours and 30 days. Tensile bond strength was determined by using an Instron Universal testing machine for the three resilient liners.

Urinary incontinence in female Parkinson disease patients. Pitfalls of diagnosis

There are many causes of urinary incontinence in the female, with stress incontinence reported as the most common. However, a high incidence of detrusor instability has been described in incontinent patients with Parkinson disease. To assess this further, urodynamic studies were performed on 17 female patients with Parkinson disease and complaints of urinary dysfunction. Detrusor instability was demonstrated in the majority of the patients (70.6%). Of the 8 patients with specific symptoms of stress incontinence, 2 were found to have a stable bladder, 3 had a hyporeflexic bladder, and 3 had detrusor instability. Surgical therapy may not be appropriate for all patients in this group. Since it is difficult to determine the causation of urinary incontinence on the basis of symptoms alone, urodynamic studies can be helpful in the evaluation of incontinent patients. This is especially important in female patients with Parkinson disease who may have detrusor instability alone or in addition to anatomic stress incontinence.

Diagnosis and grading of outflow obstruction

Urodynamic data from 66 male patients with obstruction due to benign prostatic hyperplasia were analyzed. Criteria for grading the severity of outflow obstruction based on uroflowmetry, post void residual urine, maximum bladder contraction (Pmax), and pressure during voiding (Pvoid) were developed. In selected cases, voiding cystourethrography also may be needed. These criteria help determine the need for prostatectomy. Unnecessary prostatectomies can then be avoided and can lead to significant reduction in mortality, morbidity, and health care expenses.

Relative usefulness of physical examination, urodynamics and roentgenography in the diagnosis of urinary stress incontinence

Stress urinary incontinence is a common problem in women. Accurate diagnosis of this condition is necessary for successful surgical treatment. Currently, many tests are popular. The relative value of these tests, in terms of usefulness, accuracy and practicality, has not been tested in the past. With this aim, we have compared the results from three of the most commonly performed tests, namely physical examination, urodynamics and roentgenography. It is our opinion that physical examination in the standing position is the simplest and most accurate test. Cystometrogram is important, although the yield is small. We do not advise the routine use of urethral pressure profile. For accurate determination of anatomic deformity, roentgenographic examination is the most accurate test.

Bursting strength in CO2 laser-assisted microvascular anastomoses

Iliac artery end-to-end anastomoses were performed in 42 Sprague-Dawley rats, divided into seven groups, to determine the welding effects of CO2 laser radiation in microvascular anastomoses. Conventional suture techniques were performed on right iliac arteries, and left iliac arteries were anastomosed with a laser-assisted technique. Bursting strength and diameters of the anastomotic sites were measured at different intervals (from one day to five weeks) post surgery. The anastomotic patency rate was 100 percent in both groups, and the aneurysm rate was only 2 percent in the laser group. Bursting strength was low at one and three days post surgery in both groups; then, it increased gradually until both groups could withstand higher than physiologic pressures. Results of high patency rates, low aneurysm formation, and the ability to withstand pressures higher than physiologic, suggest that the laser-assisted anastomotic technique can play an important role in microvascular surgery.

The disc-macula distance to disc diameter ratio: a new test for confirming optic nerve hypoplasia in young children

The disc-macula: disc diameter (DM:DD) ratio is the ratio of the horizontal distance between the center of the optic disc and the macula to the mean diameter of the optic disc, as evaluated from fundus photographs. The diagnosis of optic nerve hypoplasia may be difficult in cases in which the optic discs are slightly reduced in size, or when the double ring sign is absent and the condition is bilateral. The DM:DD ratio was calculated for six eyes of five children with ophthalmoscopically obvious optic nerve hypoplasia, 12 eyes of six children in whom the diagnosis of optic nerve hypoplasia was equivocal (but established by visual field examination and retinal red free photography), 13 eyes of eight children with optic atrophy, and 25 eyes of 17 children with normal optic discs. The DM:DD ratio was found to be significantly higher for both groups with optic nerve hypoplasia than for those with optic atrophy and the normal controls. For practical purposes, when the DM:DD ratio is greater than 3.0, the diagnosis of optic nerve hypoplasia should be seriously considered.

Urinary incontinence during orgasm

Urinary incontinence occurring during orgasm in women is an infrequently volunteered symptom. We studied 3 such patients to understand the mechanism behind such leakage. Urodynamic studies were performed prior to and during orgasm. It was found that during orgasm, there was involuntary bladder contraction with simultaneous urethral relaxation, resulting in leakage. Similar studies performed prior to orgasm did not reveal any involuntary bladder contraction. We believe that incontinence during orgasm is multifactorial: the most important causes are sphincter incompetence, neuropathic hyperreflexic bladder, and non-neuropathic idiopathic bladder instability.

Evidence for the involvement of DNA topoisomerase II in neutrophil-granulocyte differentiation

Agents that slow cellular proliferation usually stimulate myeloid differentiation. The demonstration in this report of an anomalous inhibitory behavior of the epipodophyllotoxin VP16-213, an agent known to inhibit the enzyme DNA topoisomerase II, prompted us to investigate the role of this enzyme in both changes in DNA supercoiling and in DNA strand breakage and reunion events occurring during the induction of neutrophil-granulocyte differentiation. We recently reported that retinoic acid, an inducer of granulocytic differentiation, stimulates transient relaxation of DNA supercoiling. We now show that this is associated with the formation of small numbers of protein-linked DNA breaks (a characteristic of topoisomerase reactions). Both events are perturbed by VP16-213, and since this agent inhibits subsequent differentiation, these observations raise the possibility of a role for DNA topoisomerase II in granulocytic differentiation. The possible relevance of these findings to mechanisms of leukemogenesis is discussed.

Contrasting patterns of DNA strand breakage and ADP-ribosylation-dependent DNA ligation during granulocyte and monocyte differentiation

Previous studies have shown that structural changes in DNA, including the ligation of pre-existing DNA breaks and the opening and closure of new breaks, occur shortly after exposure of granulomonocytic precursors (CFU-GM) to granulocyte-macrophage colony stimulating activity (GM-CSA). Monocytic differentiation of CFU-GM is selectively inhibited by compounds known to inhibit the nuclear enzyme ADP-ribosyl transferase (ADPRT). Since this enzyme, which transfers ADP-ribose units to chromatin proteins, is known to activate DNA ligase, we attempted to determine whether ligation of one or both types of DNA break is required for monocytic differentiation. Breaks in DNA were examined using the nucleoid sedimentation technique in which DNA breaks cause loss of DNA supercoiling in nucleoids and concomitant changes in their sedimentation through neutral sucrose gradients. We here report that two distinct patterns of DNA strand breakage and ligation are associated with differentiation to the granulocyte and monocyte lineages. Monocytic inducers (phorbolester and vitamin D3) predominantly produce closure of pre-existing strand breaks, whereas granulocytic inducers (granulocyte colony stimulating activity, G-CSA; retinoic acid) cause opening and closure of new breaks. Only ligation of the pre-existing breaks is highly sensitive to inhibition by 3-methoxybenzamide (a potent ADPRT inhibitor), and only monocytic differentiation is impaired by addition of this compound. These findings suggest that DNA structural changes may be directly involved in granulocyte-macrophage switching.