Search PubMed⌕ Search

Biomedical subjects

D Sims

Publications and source records attributed to D Sims.

At least 19 recordsLinked to original sources
PubMed2004

Disease modifying agent related skin reactions in multiple sclerosis: prevention, assessment, and management.

BACKGROUND: The objective for this article is to highlight some of the adverse skin manifestations associated with injectable disease modifying therapy for multiple sclerosis (MS). Early identification and intervention can often lead to minimal consequences and prolonged patient tolerance and compliance with these agents. At the University of Texas Southwestern Medical Center at Dallas and Texas Neurology in Dallas we actively follow approximately 5000 MS patients. The majority of our patients with relapsing-remitting MS (RRMS) or secondary progressive MS (SPMS) are treated with one of the currently available disease modifying agents (DMAs). Our experience with these patients, and the challenges they face in continuing long-term treatment, constitutes the basis of our proposed treatment strategies. CONCLUSION: Skin reactions in response to injectable DMA therapy in MS are generally mild. However, some reactions can evolve into potentially serious lesions culminating in infection, necrosis, and in some circumstances requiring surgical repair.

Adjuvants, Immunologic↗
PubMed2001

The human auditory brainstem response to high click rates: aging effects.

In 1999 J. Walton, M. Orlando, & R. Burkard (Hearing Research, 127, 86-94) investigated aging effects on auditory brainstem response (ABR) wave V latency using a tone-on-toneburst forward-masking paradigm. They found that at short forward-masking intervals, wave V latency shift was greater in normal-hearing older adults than in normal-hearing young adults for moderate level, high-frequency toneburst maskers and probes. It was not possible to evaluate wave I latency because stimulation and recording procedures did not produce a consistently observable wave I. In order to optimize the recording of wave I, the present study used a high-level (115 dB pSPL) click stimulus, combined with a tympanic membrane inverting electrode, and investigated the latencies and amplitudes of waves I and V across click rate. Young adults had hearing thresholds within normal limits, whereas older adults had normal hearing or mild threshold elevation. All data were collected and analyzed with a Nicolet Bravo. Using conventional recording procedures, ABRs were obtained at click rates of 11, 25, 50, and 75 Hz. Using maximum length sequences (MLSs), ABRs were obtained at 100, 200, 300, 400, and 500 Hz. Results across age groups were very similar. With increasing click rate, peak latencies increased, the I-V interval increased and peak amplitudes decreased. The most notable difference between age groups was that wave I amplitude was substantially smaller in the older subjects. It appears that changes in the ABR with increasing rate are remarkably similar in young and older adults when audiometric thresholds are normal or near-normal in both age groups.

Adult↗
PubMed2001

Drosophila transcription factor AP-2 in proboscis, leg and brain central complex development.

We report loss- and gain-of-function analyses that identify essential roles in development for Drosophila transcription factor AP-2. A mutagenesis screen yielded 16 lethal point mutant alleles of dAP-2. Null mutants die as adults or late pupae with a reduced proboscis, severely shortened legs (approximately 30% of normal length) lacking tarsal joints, and disruptions in the protocerebral central complex, a brain region critical for locomotion. Seven hypomorphic alleles constitute a phenotypic series yielding hemizygous adults with legs ranging from 40-95% of normal length. Hypomorphic alleles show additive effects with respect to leg length and viability; and several heteroallelic lines were established. Heteroallelic adults have moderately penetrant defects that include necrotic leg joints and ectopic growths (sometimes supernumerary antennae) invading medial eye territory. Several dAP-2 alleles with DNA binding domain missense mutations are null in hemizygotes but have dominant negative effects when paired with hypomorphic alleles. In wild-type leg primordia, dAP-2 is restricted to presumptive joints. Ectopic dAP-2 in leg discs can inhibit but not enhance leg elongation indicating that functions of dAP-2 in leg outgrowth are region restricted. In wing discs, ectopic dAP-2 cell autonomously transforms presumptive wing vein epithelium to ectopic sensory bristles, consistent with an instructive role in sensory organ development. These findings reveal multiple functions for dAP-2 during morphogenesis of feeding and locomotor appendages and their neural circuitry, and provide a new paradigm for understanding AP-2 family transcription factors.

Alleles↗
PubMed1999

Transdermal photopolymerization for minimally invasive implantation.

Photopolymerizations are widely used in medicine to create polymer networks for use in applications such as bone restorations and coatings for artificial implants. These photopolymerizations occur by directly exposing materials to light in "open" environments such as the oral cavity or during invasive procedures such as surgery. We hypothesized that light, which penetrates tissue including skin, could cause a photopolymerization indirectly. Liquid materials then could be injected s.c. and solidified by exposing the exterior surface of the skin to light. To test this hypothesis, the penetration of UVA and visible light through skin was studied. Modeling predicted the feasibility of transdermal polymerization with only 2 min of light exposure required to photopolymerize an implant underneath human skin. To establish the validity of these modeling studies, transdermal photopolymerization first was applied to tissue engineering by using "injectable" cartilage as a model system. Polymer/chondrocyte constructs were injected s.c. and transdermally photopolymerized. Implants harvested at 2, 4, and 7 weeks demonstrated collagen and proteoglycan production and histology with tissue structure comparable to native neocartilage. To further examine this phenomenon and test the applicability of transdermal photopolymerization for drug release devices, albumin, a model protein, was released for 1 week from photopolymerized hydrogels. With further study, transdermal photpolymerization potentially could be used to create a variety of new, minimally invasive surgical procedures in applications ranging from plastic and orthopedic surgery to tissue engineering and drug delivery.

Animals↗
PubMed1999

Transdermal photopolymerization of poly(ethylene oxide)-based injectable hydrogels for tissue-engineered cartilage.

Transdermal photopolymerization, a minimally invasive method for implantation, was used to subcutaneously place a mixture of polymer and isolated chondrocytes to regenerate cartilage tissue in vivo. Semi-interpenetrating networks of varying proportions of poly(ethylene oxide)-dimethacrylate and poly(ethylene oxide) and primary bovine articular chondrocytes were implanted in athymic mice. Four mice (12 implants) were harvested at 2, 4, and 7 weeks. Chondrocytes survived implantation and photopolymerization and formed neocartilage containing 1.5 to 2.9% wet weight collagen and 4 to 7% glycosaminoglycan. Thirty-five percent of the total collagen was type II collagen. Histologic analysis exhibited tissue structure resembling neocartilage, and safranin O staining demonstrated glycosaminoglycan distribution throughout the hydrogels. This study demonstrates the potential use of transdermal photopolymerization for minimally invasive subcutaneous implantation of hydrogels and chondrocytes for in vivo cartilage regeneration.

Animals↗
PubMed1999

Antibody response to accelerated Hib immunisation in preterm infants receiving dexamethasone for chronic lung disease.

AIM: To study the effect of dexamethasone on the routine immunisation of preterm infants with chronic lung disease. METHODS: Serum samples were obtained before and after immunisation from an unselected cohort of 59 preterm infants. Haemophilus influenzae antibodies were measured using an ELISA method and differences in the geometric mean values between the two groups of babies analysed. RESULTS: Sixteen infants received no dexamethasone. Before and after immunisation antibody titres for those receiving no dexamethasone were 0.16 and 4.63 mcg IgG/ml. Corresponding values for those receiving dexamethasone were 0.10 and 0.51 mcg IgG/ml, respectively. CONCLUSION: Dexamethasone used in the treatment of chronic lung disease seems to significantly affect the antibody response of preterm infants to immunisation against Haemophilus influenzae.

Anti-Inflammatory Agents↗
PubMed1999

A personal triumph.

Explore the source record for details and available documents.

Awards and Prizes↗
PubMed1998

The phenomenology of post-traumatic stress disorder. A symptomatic study of 70 victims of psychological trauma.

This study analyses and categorises the subjective experiences and psychological symptoms of those involved in a major disaster but not themselves physically injured. It examines the concept of post-traumatic stress disorder (PTSD) and relates it to other psychiatric diagnoses and also to the particular nature of the disaster. 70 police officers are the subjects of this study, 59 men and 11 women, all of them involved in the Hills-borough Football Stadium Disaster. Assessment included detailed psychiatric history and examination with an account of the events experienced by the informants and their psychological reaction to this at the time and subsequently. Psychiatric diagnosis was made and quantified measurements were also recorded, including a rating scale for the criteria of PTSD, the General Health Questionnaire and rating scales for depression and anxiety. Severity of PTSD symptoms was associated with higher scores on rating scales for both depressive and anxiety symptomatology. Subjective depressive symptoms and depersonalisation were associated with severity of PTSD. Frustrated helplessness was a recurring theme in the psychopathology. Alcohol consumption of those who were already drinkers increased. Social functioning at work and in marriage deteriorated with increased severity of PTSD. Although PTSD has features that distinguish it from other conditions, the degree of distress and long-term disability is more related to depressive symptomatology than to the severity of PTSD itself.

Adaptation, Psychological↗
PubMed1995

Negative laparotomy in abdominal gunshot wounds: potential impact of laparoscopy.

OBJECTIVE: To evaluate the morbidity and hospital stay resultant from negative exploratory laparotomy (NL) for abdominal gunshot wounds (ABGSWs) and the potential impact the use of diagnostic laparoscopy (DL) could have on these variables. DESIGN: A retrospective study was conducted. MATERIALS AND METHODS: The charts of all patients with ABGSWs over a 4-year period were reviewed. Data was collected on injuries, rate of NL, morbidity and hospital stay. This was compared to a subsequent group of patients with ABGSWs managed with a DL protocol. MEASUREMENTS AND MAIN RESULTS: Over a 4-year period, 817 patients had exploratory laparotomy (EL) for ABGSWs. The NL rate was 12.4% (101 of 817); 69 of these patients had no associated injury or other procedures. They had a 22% morbidity and an average hospital stay of 5.1 days. Subsequently, 85 patients with ABGSWs underwent DL. This group was similar to the EL group and would have undergone EL prior to the introduction of DL at our institution. In this group, 34 patients had no associated injury or other procedures. They had a 3% morbidity, and their average hospital stay was 1.4 days. The morbidity and hospital stay were statistically significantly reduced (p < 0.01) in patients with negative DL versus NL. CONCLUSIONS: These data demonstrate that NL is associated with a high morbidity and long hospital stay. The use of DL can reduce the rate of NL, and result in lower morbidity and shorter hospital stay in patients with ABGSWs.

Abdominal Injuries↗
PubMed1994

Heterogeneity of pericyte populations in equine skeletal muscle and dermal microvessels: a quantitative study.

The objective of this ultrastructural investigation was to determine if populations of pericytes in equine dermal and skeletal muscle capillaries increase in a head-to-foot direction, as has been reported in human skeletal muscles. Samples of equine microvessels were obtained from the longissimus dorsi skeletal muscle 150 cm. from the ground, from the dermis above this muscle, from the extensor carpi radiali muscle at 55 cm. from the ground, from the dermis adjacent to that muscle, and from dermis 15 cm. from the ground, just above the hoof wall. Tissues were processed for transmission electron microscopy. Electron micrographs were analyzed with a digitizing tablet and computer, to determine the ratios of endothelial cell outer circumference and pericyte inner lengths. Pericytes were separated into two classes; those closest to the endothelial cells were defined as covering capillaries. Those separated from endothelial cells by another layer of pericytes were termed enveloping pericytes. There was much greater coverage and envelopment of dermal capillaries (85% and 135%) than skeletal muscle capillaries (27% and 31%). Regression analysis of the pericyte coverage and envelopment of dermal capillaries revealed a significant increase in pericytes toward the ground. Similarly, the two skeletal muscle tissues differed significantly in their pericyte coverage and envelopment (25/27% at 150 cm., 31/35 at 55 cm.). The data indicate that, as in humans, capillary pericytes are not homogeneously distributed within the same tissues, but are more numerous closer to the ground. Differences in pericyte populations could affect studies of microvessel function.

Analysis of Variance↗
PubMed1993

Top teams.

Explore the source record for details and available documents.

Medicine↗
PubMed1993

Clinical management. The case of the consultant psychiatrist.

Review the management role of consultant psychiatrists in the light of recent NHS reforms. Tries to identify the needs of clinicians and their patients and what is causing dissatisfaction within the profession. Examines various reforms. Concludes that although difficult, the care leadership within the psychiatric area should lie with the consultant psychiatrist who should have the experience necessary in order to define the qualifications and care necessary for each patient.

Mental Health Services↗
PubMed1992

Laparoscopic evaluation of tangential abdominal gunshot wounds.

The use of laparoscopy in abdominal trauma has been proposed for several decades; however, it has not been widely used. With the advent of laparoscopic cholecystectomy, general surgeons are realizing the potential of this technique. This should result in an expanded role for laparoscopy, including the evaluation of abdominal trauma. We present a series in which laparoscopy was used in the evaluation of tangential gunshot wounds to the abdomen. Laparoscopy enabled us to demonstrate whether the missile had violated the peritoneal cavity and to avoid laparotomy in cases without peritoneal penetration.

Abdominal Injuries↗
PubMed1987

Efficacy of levamisole and netobimin against Haemonchus contortus in lambs in Louisiana.

Efficacy of levamisole was evaluated in a suspected levamisole-resistant population of Haemonchus contortus in the Louisiana State University sheep flock. The efficacy of netobimin also was evaluated against this population of Haemonchus. In trial 1, 5 lambs naturally infected with H contortus were given 8 mg of levamisole/kg of body weight as a drench, and 5 lambs were not treated (controls). Nematode recovery after slaughter indicated 0% efficacy against H contortus. In trial 2, 30 nematode-free lambs were each given 8,300 F1 generation infective larvae of H contortus, which were derived from parent H contortus that survived 2 levamisole treatments in lambs being maintained in a nematode-free environment. Ten lambs were treated with 8 mg of levamisole/kg as a drench, 10 were treated with 20 mg of netobimin/kg as a drench, and 10 were not treated (control). Nematode recovery after slaughter revealed 62.3% and 99.8% efficacy for levamisole and netobimin, respectively, against H contortus.

Animals↗
PubMed1986

A prospective study of inhibitive casting as an adjunct to physiotherapy for cerebral-palsied children.

The effect of a three-week course of inhibitive casting and neurodevelopmental therapy on the static muscle tonus, developmental skills, passive range of ankle dorsiflexion and gait pattern was determined in 32 cerebral-palsied children. Two weeks after treatment, passive range of ankle dorsiflexion and foot-floor contact in walking had improved significantly but there was no significant change in the static muscle tone or developmental skills. After five months the improvements in ankle dorsiflexion and walking pattern were no longer evident. Further objective studies to determine the effect of 'inhibitive casting' are necessary before the modality is used indiscriminately.

Ankle↗