Biomedical subjects

J P Newman

Publications and source records attributed to J P Newman.

At least 19 recordsLinked to original sources

PubMed2000

Review of closed dressings after laser resurfacing.

BACKGROUND: Laser skin resurfacing has become an accepted technique for the treatment of facial rhytides and associated solar skin damage. Achieving a successful result is directly related to proper postoperative wound care during the reepithelialization process. There are open and closed approaches to the treatment of the post-laser resurfacing patient with distinct advantages and disadvantages. OBJECTIVE: To review the most commonly used closed dressings after facial laser skin resurfacing and compare their advantages and disadvantages. To compare clinical findings with a group of patients treated exclusively with an open technique. METHODS: Review of composite foams, polymer film, polymer mesh, and hydrogel products and prospective observations of clinical outcomes of patients treated with each dressing category after facial laser skin resurfacing. We perform a retrospective chart review of a group of patients treated exclusively with an open technique comparing crust formation, comfort, and pruritus with the prospective group of patients treated with closed dressings. RESULTS: The closed dressings available today each have unique structural configurations and adhesive properties intended to maintain an occlusive wound environment. Patient acceptance of these dressings was favorable, with improved comfort compared to the open dressing group. Complications of bacterial infections and contact dermatitis were not observed when closed dressings were used with a protocol for dressing changes performed at 48 hours. Rates of reepithelialization did not vary according to dressing category. Crust formation and postoperative pruritus occurred less frequently when closed occlusive dressings were worn by patients. CONCLUSIONS: When used properly, these dressings improve patient comfort, simplify their postoperative wound care, and do not increase the risk of infection or contact dermatitis. Overall satisfaction was highest with perforated mesh and polymer dressings for full-face wounds.

Adult↗

PubMed2000

Hemodynamic and metabolic responses to moderate asphyxia in brain and skeletal muscle of late-gestation fetal sheep.

The purpose of this study was to investigate metabolic and hemodynamic responses in two fetal tissues, hindlimb muscle and brain, to an episode of acute moderate asphyxia. Near-infrared spectroscopy was used to measure changes in total hemoglobin concentration ([tHb]) and the redox state of cytochrome oxidase (COX) simultaneously in the brain and hindlimb of near-term unanesthetized fetal sheep in utero. Oxygen delivery (DO(2)) to, and consumption (VO(2)) by, each tissue was derived from the arteriovenous difference in oxygen content and blood flow, measured by implanted flow probes. One hour of moderate asphyxia (n = 11), caused by occlusion of the maternal common internal iliac artery, led to a significant fall in DO(2) to both tissues and to a significant drop in VO(2) by the head. This was associated with an initial fall in redox state COX in the leg but an increase in the brain. [tHb], and therefore blood volume, fell in the leg and increased in the brain. These data suggest the presence of a fetal metabolic response to hypoxia, which, in the brain, occurs rapidly and could be neuroprotective.

Acid-Base Equilibrium↗

PubMed2000

Generality of Psychopathy Checklist-Revised factors over prisoners and substance-dependent patients.

The Psychopathy Checklist-Revised (PCL-R; R. D. Hare, 1991) is an often-used device for assessment of adult antisociality. This research examined generalizability by replicating the 2-factor model for a sample of 326 male prisoners and assessing its congruence and relative reliability and specificity among 620 substance-dependent patients. Generality was assessed also across addiction subtypes (opioid, cocaine, and alcohol), age, gender, and ethnicity. The 2-factor model was found inappropriate for the substance-dependent samples, whereas a unidimensional model represented by the PCL-R total score was found generalizable across prison and substance-dependent samples.

Adolescent↗

PubMed1999

Are all psychopathic individuals low-anxious?

Theorists commonly assume that true or primary psychopathic individuals experience little anxiety or neurotic conflict. This study examined the relationship between psychopathy and anxiety in 104 Caucasian and 113 African American incarcerated men using the Psychopathy Checklist--Revised (PCL-R; R. D. Hare, 1991) and multiple self-report measures to tap diverse interpretations of the anxiety construct (i.e., neuroticism, traditional definitions of anxiety, and fear). Analyses involving zero-order, semipartial, and point-biserial correlations indicate that PCL-R psychopathy and the anxiety construct are essentially independent. These findings suggest that either (a) the traditional belief that all psychopathic individuals are low-anxious is incorrect or (b) the PCL-R is not an adequate measure of primary psychopathy.

Adult↗

PubMed1999

Testing Damasio's somatic marker hypothesis with psychopathic individuals: risk takers or risk averse?

Damasio and colleagues (A. R. Damasio, 1994; A. R. Damasio, D. Tranel, & H. Damasio, 1990) have theorized about a possible relationship between somatic markers and the behavior of psychopathic individuals (Ps), but, to date, there are no published data regarding the proposed relationship. The authors assessed 86 Caucasian and 71 African American male offenders using R. D. Hare's (1991) Psychopathy Checklist--Revised and used a modified version of Bechara and colleagues' (A. Bechara, A. R. Damasio, H. Damasio, & S. W. Anderson, 1994; A. Bechara, H. Damasio, D. Tranel, & A. R. Damasio, 1997) gambling task to test the hypothesis that Ps would, consistent with the somatic marker hypothesis, fail to become risk averse. Results indicated that level of anxiety, but not psychopathy, was predictive of response choices. Several limitations and implications of the study are noted.

Adult↗

PubMed1998

Open channel block and open channel destabilization: contrasting effects of phenol, TEA+ and local anaesthetics on Kv1.1 K+ channels.

(1) Voltage-gated K+ channels are inhibited by a variety of clinical and experimental drugs. (2) Complex changes in channel gating suggest mechanisms in which drug affinity depends on channel state. (3) Here, we use the effects of external TEA+, two local anaesthetics (lidocaine and bupivacaine), and phenol on rat brain Kv1.1 K+ channels expressed in Xenopus oocytes to illustrate three mechanisms. (4) The open state has the highest affinity in the local anaesthetic model but the lowest in the phenol model, and while local anaesthetics simply block the open channel, phenol can produce a conducting but destabilized open state. (5) All states have equal affinity for external TEA+.

Anesthetics, Local↗

PubMed1998

Closed dressings after laser skin resurfacing.

OBJECTIVE: To evaluate the safety, efficacy, and patient acceptance of closed dressings after full facial resurfacing with the carbon dioxide laser. DESIGN: Prospective cohort of men and women undergoing full facial carbon dioxide laser resurfacing. SETTING: Ambulatory surgical center at a university hospital. PATIENTS: Forty consecutive patients randomized to 1 of 4 dressing groups. INTERVENTIONS: All patients underwent full facial resurfacing with a carbon dioxide laser system. One of 5 closed dressings (single- or 3-layer composite foam, plastic mesh, hydrogel, or polymer film) was placed immediately after the procedure. Closed dressings were changed on postoperative day 2 and removed on postoperative day 4. OUTCOME MEASURES: Objective postoperative criteria of erythema, scarring, reepithelialization, and surface irregularities were recorded and photodocumented. Comparisons were made among the closed dressing groups as well as with a group of historical control subjects treated with open dressings. The ease of application, office time for preparation and application, and cost of the individual dressings were collected. Patient characteristics of overall acceptance, comfort, and ease of maintenance were recorded with a visual analog scale. RESULTS: There were no complications of scarring, surface irregularities, or contact dermatitis from the application or maintenance of the closed dressings. There were no significant differences in the number of days of postoperative erythema or in the rate of facial reepithelialization among the groups. Most patients preferred not to continue with the closed dressings past 2 days. Positive features from the use of closed dressings included reduction in crust formation, decreased pruritus, decreased erythema, and decreased postoperative pain, compared with historical controls. Negative features included time in preparation and application of the dressings. Costs ranged from $9.79 to $50 per dressing change. CONCLUSIONS: Closed dressings are safe and offer benefits noted during the first 4 postoperative days. Patients can be expected to maintain a closed dressing for at least 24 hours but no longer than 4 days. The positive features of closed dressings and patient acceptance outweigh the cost and office time involved with their application and maintenance.

Adult↗

PubMed1998

Management of the clinically positive neck in organ preservation for advanced head and neck cancer.

BACKGROUND: To investigate clinicopathologic predictive criteria for the optimal management of neck metastases in patients with advanced head and neck cancers treated with combined chemoradiotherapy. METHODS: Prospective study, 48 patients. Mean length follow-up, 23 months. RESULTS: Neck stage predicted neck response to chemoradiotherapy; N3 necks showed more partial responses (P = 0.04), and N1 necks showed more complete responses (P = 0.12). Primary tumor site strongly predicted the pathologic response found on neck dissection in patients with a clinical partial response (cPR) following chemoradiotherapy. There was no difference in survival between patients with a clinical complete response (cCR) after chemoradiotherapy, and patients with a pathologic complete response (pCR) after neck dissection (P = 0.20); however, when grouped together, these patients survived longer than did patients with a pPR at neck dissection (P = 0.06). CONCLUSIONS: Clinical response to induction chemotherapy is a poor predictor of ultimate neck control. Induction chemotherapy followed by chemoradiotherapy, and planned neck dissection for patients with persistent cervical lymphadenopathy, provides good regional control.

Adult↗

PubMed1998

Passive avoidance in psychopathic offenders: a replication and extension.

A passive avoidance task was administered to 97 Caucasian and 110 African American offenders to (a) replicate prior research demonstrating poor passive avoidance in psychopathic individuals (Ps) with low anxiety, (b) compare the effects of anxiety, neuroticism, and fear in identifying subgroups of Ps and controls who differ in passive avoidance, and (c) reevaluate the generalizability of this finding to African American offenders. Replicating past research with Caucasian offenders, low-anxious Ps committed significantly more passive avoidance errors than low-anxious controls. Although this difference was also found in Ps and controls with low neuroticism scores, the comparison involving low-fear offenders failed to reach significance. As in past research, comparable comparisons involving African American offenders were not statistically significant.

Adult↗

PubMed1998

Advantages and disadvantages of computer imaging in cosmetic surgery.

BACKGROUND: Despite the growing popularity of computer imaging systems, it is not clear whether the medical and legal advantages of using such a system outweigh the disadvantages. OBJECTIVE: The purpose of this report is to evaluate these aspects, and provide some protective guidelines in the use of computer imaging in cosmetic surgery. METHODS: The positive and negative aspects of computer imaging from a medical and legal perspective are reviewed. Also, specific issues are examined by a legal panel. RESULTS: The greatest advantages are potential problem patient exclusion, and enhanced physician-patient communication. Disadvantages include cost, user learning curve, and potential liability. CONCLUSION: Careful use of computer imaging should actually reduce one's liability when all aspects are considered. Recommendations for such use and specific legal issues are discussed.

Communication↗

PubMed1997

Transcalvarial suture fixation for endoscopic brow and forehead lifts.

OBJECTIVE: To evaluate the safety and effectiveness of transcalvarial suture fixation during endoscopic repair of brow ptosis. DESIGN: Case series. SETTINGS: A private ambulatory surgicenter and a Veterans Affairs Hospital. PARTICIPANTS: Fifty patients with brow ptosis with minimum follow-up of 12 months. RESULTS: Patients had improvement in brow position in all cases. There were no adverse effects of performing cortical tunnels and suture fixation. CONCLUSION: Transcalvarial suture fixation can be performed safely with good to excellent results and avoids the need for screw or plate fixation.

Endoscopy↗

PubMed1997

Distortion of the auriculocephalic angle following rhytidectomy. Recognition and prevention.

Distortion of ear protrusion after rhytidectomy results in an aesthetically unfavorable appearance. We have seen cases in which the auriculocephalic angle has widened postoperatively, producing a noticeable deformity. Herein, we report 3 cases that resulted in abnormal postsurgical ear protrusion. We also discuss prevention through the use of conchal setback sutures.

Adult↗

PubMed1997

The impact of motivationally neutral cues on psychopathic individuals: assessing the generality of the response modulation hypothesis.

Psychopathic individuals' lack of responsiveness to punishment cues and poor self-regulation have been attributed to fearlessness (D. T. Lykken, 1957, 1982, 1995). Alternatively, deficient response modulation (RM) may hinder the psychopathic individual's processing of peripheral information and self-regulation when they are engaged in goal-directed behavior (C. M. Patterson & J. P. Newman, 1993). Although more specific than the fearlessness hypothesis in some respects, the RM hypothesis makes the more general prediction that psychopathic individuals will have difficulty processing motivationally neutral as well as fear-related stimuli. The authors assessed this prediction by using psychopathic and nonpsychopathic male inmates subdivided by level of anxiety/negative affectivity (NA). As predicted by the RM hypothesis, peripheral presentation of motivationally neutral cues produced significantly less interference in low-NA psychopathic individuals than in low-NA controls.

Adult↗

PubMed1997

Approach and avoidance motivation in psychopathic criminal offenders during passive avoidance.

The authors evaluated competing theories that attribute psychopathic individuals' poor passive avoidance to a strong activating system, a weak inhibitory system, or poor modulation of behavioral activation when inhibitory cues appear. In Study 1, the continuous motor task involved a reward phase to elicit the activating system followed by a passive avoidance phase. Study 2 tested the generality of the theories by using an active avoidance phase to elicit the activating system. Heart rate and response speed results from Study 1 best supported the strong activating system and poor response modulation models in low-anxiety psychopathic offenders. Study 2 results did not clearly support any of the models. Further research is needed to determine if excessive activation by reward and poor response modulation are associated with passive avoidance deficits and other characteristics of low-anxiety psychopathic offenders.

Adult↗

PubMed1997

Legal issues of computer imaging in plastic surgery: a primer.

Although plastic surgeons are increasingly incorporating computer imaging techniques into their practices, many fear the possibility of legally binding themselves to achieve surgical results identical to those reflected in computer images. Computer imaging allows surgeons to manipulate digital photographs of patients to project possible surgical outcomes. Some of the many benefits imaging techniques pose include improving doctor-patient communication, facilitating the education and training of residents, and reducing administrative and storage costs. Despite the many advantages computer imaging systems offer, however, surgeons understandably worry that imaging systems expose them to immense legal liability. The possible exploitation of computer imaging by novice surgeons as a marketing tool, coupled with the lack of consensus regarding the treatment of computer images, adds to the concern of surgeons. A careful analysis of the law, however, reveals that surgeons who use computer imaging carefully and conservatively, and adopt a few simple precautions, substantially reduce their vulnerability to legal claims. In particular, surgeons face possible claims of implied contract, failure to instruct, and malpractice from their use or failure to use computer imaging. Nevertheless, legal and practical obstacles frustrate each of those causes of actions. Moreover, surgeons who incorporate a few simple safeguards into their practice may further reduce their legal susceptibility.

Communication↗

PubMed1997

Surgical morbidity of neck dissection after chemoradiotherapy in advanced head and neck cancer.

The use of chemotherapy and irradiation for organ preservation attempts to eliminate the need for extensive surgery in patients with advanced squamous cell carcinoma of the head and neck (SCCHN). We sought to characterize the morbidity of surgery in patients who needed surgery after treatment with induction chemotherapy followed by simultaneous chemotherapy and radiotherapy (chemoradiotherapy). The surgical morbidity within the first 30 postoperative days of 17 patients treated in an organ preservation approach between July 1991 and December 1994 was compared with a control group of patients undergoing similar surgical procedures during the same period. The organ preservation study patients underwent surgical procedures consisting of 18 neck dissections and 5 resections of the primary site. Six patients in the organ preservation study group experienced 8 surgical complications within the first 30 postoperative days, and most complications were minor. There was no significant difference in the duration of surgery or length of hospitalization between study patients and matched controls. Our surgical complication rate (35.3%) was higher but not statistically different from that of the control group, and compared favorably to reports of surgical morbidity (44% to 61%) in the literature on patients treated with chemoradiotherapy. The lower complication rate seen in this study may be a reflection of early surgical intervention as part of our organ preservation study scheme, the preponderance of neck dissections performed, and the limited number of pharyngeal procedures performed.

Adult↗

PubMed1996

Ciliary neurotrophic factors enhances peripheral nerve regeneration.

BACKGROUND: Adjunctive measures to enhance nerve repair have focused on a variety of trophic factors that alter the physiologic response to nerve injury through Schwann cell-axonal interactions. OBJECTIVE: To evaluate the effects of two trophic factors, ciliary neurotrophic factor and nerve growth factor, on axonal response to injury. DESIGN: A prospective, randomized, blinded animal study with a placebo control using lactated Ringer's solution. INTERVENTION: Rat sciatic nerves were transected and repaired as a model of injury following which experimental factors were delivered in vivo through an implantable osmotic pump. OUTCOME MEASURES: Functional nerve recovery, muscle mass, and gene expression in the three experimental groups were evaluated. RESULTS: The ciliary neurotrophic factor group (n=6) showed a higher sciatic functional recovery (P=.003) and preservation of affected muscle mass (P=.03) compared with the nerve growth factor (n=8) and control (n=8) groups. Molecular analysis of injured nerves showed no difference in expression of ciliary neurotrophic factor, myelin basic protein, or low-affinity neurotrophin receptor messenger RNA among the three groups. CONCLUSION: These data suggest that ciliary neurotrophic factor may serve as an important neurocytokine for axonal regrowth during peripheral nerve regeneration.

Animals↗

PubMed1996

Combined use of superpulsed carbon dioxide laser and cryotherapy for treatment of facial rhytids.

OBJECTIVE: To compare the effect of superpulsed carbon dioxide (CO2) laser alone with that of cryotherapy in combination with CO2 laser in treatment of facial rhytids. DESIGN: A randomized prospective study. SETTING: Facial Plastic Surgery Clinic at Standford University Medical Center, Standford, Calif. PATIENTS: Twenty patients with perioral rhytids were randomized in the study, 11 in the laser group and 9 in the cryotherapy and laser group. INTERVENTION: Patients in the laser group were treated with superpulsed CO2 laser. Initially, the shoulders of rhytids were spot treated. The area was then wiped and rehydrated. The entire surface was then treated with a second pass. A third pass, if deemed necessary, was then used to treat the shoulders. Patients in the combined group underwent cryotherapy of the entire perioral region followed by CO2 laser treatment similar to that previously described. MAIN OUTCOME MEASURE: Improvement in facial rhytids with laser treatment alone was compared with improvement using cryotherapy and laser. A skin wrinkle grading system was used and patients were graded by 3 independent observers. Close-up photographs were obtained preoperatively and postoperatively. A questionnaire was filled out by each patient 1 month following treatment and was used to rate overall patient satisfaction. RESULTS: There was no statistically significant difference between the 2 groups regarding final outcome, amount of anesthetic agents required for each patient, or rate of complications. CONCLUSION: Superpulsed CO2 skin resurfacing alone is as effective as combined cryotherapy and superpulsed CO2 laser for treatment of perioral rhytids.

Cryotherapy↗