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J Schwab

Publications and source records attributed to J Schwab.

At least 19 recordsLinked to original sources
PubMed2004

[Craniotomy and the temporal branch of the facial nerve].

The surgical anatomy of the temporal branch of the facial nerve was studied in the anatomical laboratory. The temporal branch divides into an anterior, middle (frontal), and a posterior ramus after it pierces the parotid fascia. The anterior ramus innervates orbicularis oculi and corrugator supercilii muscles; the middle branch is for the ipsilateral frontalis muscle. The posterior branch innervates the anterior and superior auricular and tragus muscles. Below the zygomatic arch, the temporal branch of the facial nerve is located in the subcutaneous tissue. Above the arch, it continues in the subgaleal space with the superficial temporal fascia deeply. The terminal twigs of the temporal branch penetrate the galea to reach their target muscles that are all located superficial to the galea. There is a significant variability in the course of the temporal branch of the facial nerve. Occasionally, the terminal twigs of the middle ramus may penetrate superficial layer of superficial temporal fascia and run in the intrafascial fat pad before entering the frontalis muscle. There are four available operative techniques in this anatomical location. The subgaleal dissection of a temporofrontal scalp flap is associated with a high incidence of postoperative palsy of the temporal branch of the facial nerve and cosmetically bothersome results. Reflecting the scalp and temporalis muscle together as a single layer is the safest procedure. Unfortunately, this technique can not be used for the transzygomatic approaches and the bulky temporalis muscle may compromise basal exposure in the pterional route. Third technique was described and propagated by Yasargil. He proposed a subgaleal dissection up to the anterior one-fourth of the temporalis muscle where the dissection has to be deepened between the two layers of the superficial temporal fascia (in the interfascial fat pad). This approach may also infrequently injure the temporal branch in case of anatomical variation. The last available operative technique raises the superficial temporal fascia together with the scalp.

Craniotomy↗
PubMed2003

Improved functional cardiac MR imaging using the intravascular contrast agent CLARISCAN.

PURPOSE: Using segmented k-space turbo gradient echo MR techniques (TGE) contrast between blood and myocardium is often reduced in long axis views due to reduced in plane spin-refreshment, particularly in patients with low ejection fraction. The application of an intravascular contrast agent (CA) may improve endocardial border delineation. MATERIALS AND METHODS: In 15 patients cardiac cine loops in two long axis and two short axis views were acquired during breath hold using a TGE sequence without and with increasing doses of CA (0.75, 2.0, 5.0 mg Fe/kg). Two independent observers evaluated left ventricular function (LVEF, modified Simpson's rule) and assigned a visual score (range: 0 = 'not visualized' to 6 = 'excellent visualization') for endocardial border delineation. Signal- and contrast-to-noise ratios (SNR; CNR) were determined. RESULTS: Endocardial border delineation score for TGE was 1.7 +/- 0.6 and 3.9 +/- 0.6**, 4.4 +/- 0.5**, 4.6 +/- 0.4** for 0.75, 2.0, 5.0 mg Fe/kg of CA, respectively (**p < 0.01 vs. TGE). SNR of blood increased significantly with any dose of CA with a mild drop of myocardial SNR resulting in a significant increase of CNR blood/myocardium. The maximum effect with 2.0 mg Fe/kg was a >2-fold CNR increase. Inter- and intraobserver variability assessed according to the method of Bland-Altmann was reduced at 2.0 mg Fe/kg for determination of LVEF and reached statistical significance for LVEF <50%. CONCLUSION: Intravascular CA increased CNR between blood and myocardium by a factor >2 and significantly improved the determination of cardiac volumes. The benefit in accuracy was most for patients with left ventricular ejection fraction <50%.

Aged↗
PubMed2001

Transient in vivo activation of rat brain macrophages/microglial cells and astrocytes by immunostimulatory multiple CpG oligonucleotides.

Certain DNA sequences containing motifs of unmethylated CpG nucleotides are immunostimulatory and might contribute to the development of inflammatory lesions after infections. CpG motifs might further contribute to side effects of oligonucleotide-based therapeutic approaches. Here we have analyzed the effects of intracranial injections of synthetic CpG oligonucleotides. We observed that oligonucleotides with several unmethylated CpG motifs, but not methylated or inverted GpC motifs, stimulated microglial cells and astrocytes of the rat brain. This transient, self-limiting response is maximal at day 3 after injection and subsides until day 5. Activated microglial cells could be identified to produce two novel monocytic peptides, the allograft inflammatory factor-1 (AIF-1) and endothelial monocyte activating polypeptide II (EMAP II). Astrocytes were similarly activated as shown by expression of the enzyme heme-oxygenase-1 (HO-1). Glial cell proliferation (expression of PCNA) or aptosis was not observed. Thus immunostimulatory DNA activates the local innate immune defense system of the brain, and might contribute transiently to infectious, inflammatory and degenerative responses of the central nervous system.

Animals↗
PubMed2001

Pediatric residency training on tobacco: training director tobacco survey.

BACKGROUND: Statements from the American Academy of Pediatrics encourage pediatricians to address tobacco. However, most fail to do so and little is known about the preparation to intervene on tobacco they receive during residency training. METHODS: The Pediatric Residency Training Director Tobacco Survey was mailed to all pediatric residency training directors in the United States. The survey assessed the nature of training and supervision on tobacco, barriers to training, and factors that influence the inclusion of tobacco in the residency training curriculum. RESULTS: Seventy percent of the training directors returned the surveys. Relatively few offered training/supervision on tobacco on a formal basis. Training directors were reluctant to treat parents who smoke, were skeptical about third party payer reimbursement, and did not believe that office-based interventions for treating tobacco use among patients were effective. Key barriers to training were competing priorities, lack of training resources, and lack of faculty with expertise on tobacco. CONCLUSION: Residency training is an excellent time to train future pediatricians to intervene on tobacco, but too few pediatric training programs have taken up this charge. Much needs to be done to correct this situation and to prepare future pediatricians to meet the tobacco challenge.

Attitude of Health Personnel↗
PubMed2001

Silencing of CD21 expression in synovial lymphocytes is independent of methylation of the CD21 promoter CpG island.

The complement receptor II (CD21) recognises the complement component C3d of immune complexes. Expression of the CD21 gene is tightly regulated during B lymphocyte differentiation. Only mature B lymphocytes express CD21 but not pro-, pre-, or plasma B lymphocytes. Previously we found that pro-, pre-, and intermediate B lymphocytes contain a methylated CpG island and do not express CD21. CD21-expressing mature B lymphocytes, plasma B lymphocytes, and nonlymphoid cells carried a demethylated CD21 CpG island. Furthermore, we found that synovial lymphocytes from patients with rheumatic disease show reduced expression of CD21. This observation tempted us to analyse the methylation status of the CD21 CpG island in peripheral blood mononuclear cells and synovial fluid mononuclear cells derived from these patients. While methylation is involved in silencing CD21 in early types of B lymphocytes, we found the CD21-CpG island to be demethylated in peripheral blood mononuclear cells and synovial fluid mononuclear cells of patient DNA.

Aged↗
PubMed2001

Jejunal manometry predicts tube feeding intolerance in the postoperative period.

Postoperative nutrition is best provided enterally; however, patients often develop intolerance to enteral feedings. Our aim was to prospectively identify abdominal examination and jejunal pressure activity associated with postoperative intolerance of enteral feedings. Twenty-nine patients underwent abdominal operation and needle catheter jejunostomy placement. Elemental tube feedings were started on the day after surgery and advanced to the caloric goal rate over three days. Patients whose feedings were slowed at the attending surgeon's discretion were defined as intolerant. Jejunal manometry and a standardized abdominal exam were performed on postoperative days 1, 3, and 5. Fifteen patients (52%) were intolerant of tube feedings and had decreased jejunal motor activity but more active bowel sounds prior to feedings. After feedings, intolerant patients developed abdominal distension, but other abdominal findings were inconsistent. A marked decrease in phase II of the migrating motility complex (MMC) and the lack of a fed response were present in both groups. The overall jejunal motility present on day 1 following surgery identifies patients that will not tolerate enteral feedings. The abdominal examination, MMC parameters, and motor response to feeding did not predict feeding intolerance.

Colectomy↗
PubMed2001

Regulation of CD21 expression by DNA methylation and histone deacetylation.

The complement receptor II (CD21) serves as a receptor for the complement component C3d of immune complexes on B lymphocytes. Expression of the CD21 gene is tightly regulated during B lymphocyte differentiation. Only mature B lymphocytes, but not pro-, pre- or plasma B lymphocytes, express CD21. There is evidence that cell type-specific expression is mediated by a silencer element located in the first intron. The CD21 promoter region contains a CpG island adjacent to the ATG start codon. We have analyzed the methylation status of this CpG island in B lymphoid cell lines representing the various differentiation stages of B lymphocyte development and primary lymphocytes. We found that the pro-, pre- and intermediate B lymphocytes contain a methylated CpG island and do not express CD21, whereas CD21-expressing mature B lymphocytes, plasma B lymphocytes and non-lymphoid cells carry a demethylated CD21 CpG island. To analyze whether the lack of CD21 expression in early B lymphocytes is due to inhibition by CpG methylation we have used 5-aza-2'-deoxycytidine to inhibit DNA methyltransferase activity. Treatment of pro-B lymphocytes with the drug resulted in expression of CD21. We have also applied Trichostatin A (TSA), an inhibitor of histone deacetylation, to determine whether the state of histone deacetylation affects the expression of CD21. We found that TSA induces expression of CD21 in early B lymphocytes. Thus CD21 expression is controlled by both methylation of the CD21 CpG island and chromatin modification through histone deacetylation in early B lymphocyte development.

Acetylation↗
PubMed2001

Pediatric residency training on tobacco.

OBJECTIVE: Pediatricians have a unique role to play in the antismoking arena. However, few pediatric residency training programs prepare residents to meet the tobacco challenge. This study evaluates the effects of a comprehensive pediatric residency training program on tobacco on resident tobacco intervention behaviors, as well as on changes in the behavior of patients and their parents/guardians. METHODS: Pediatric residents were exposed to a comprehensive training program on tobacco. Baseline and follow-up surveys of residents, parents/guardians, and patients were used to assess the effects of the training program. A quasi-experimental design permitted unambiguous evaluation of the program's effects on resident intervention behaviors. RESULTS: The comprehensive training program on tobacco led to marked and significant changes in resident intervention on tobacco. Many of these changes were supported by parents' and patients' reports. In turn, resident intervention on tobacco led to a significant increase in the likelihood that parents would maintain a "smoke-free household." Significant changes in the prevalence of parental smoking were not found, although the trend during 3 years of follow-up was in the desired direction. A high proportion of residents reported that they intervened on tobacco in patients at baseline and follow-up, but too few patients were sampled to permit analysis of the impact on changes in smoking. CONCLUSIONS: Comprehensive training on tobacco had a positive and powerful effect on the tobacco intervention behavior of pediatric residents. In turn, intervention on tobacco by pediatric residents may have a significant impact on patients and their parents. These findings underscore the efficacy of pediatric residency training on tobacco, and it is hoped that they will serve as an impetus for other pediatric residency programs to introduce training on tobacco.

Adolescent↗
PubMed2000

Antibiotic prophylaxis in percutaneous endoscopic gastrostomy (PEG)--results from a prospective randomized multicenter trial.

OBJECTIVE: To determine the efficacy of antibiotic prophylaxis in percutaneous endoscopic gastrostomy (PEG) as a part of a standardized regimen. METHODS: An open prospective randomised multicenter study in 216 patients. 106 received ceftriaxone 1 g i.v. 30 min preinterventionally and 110 no study medication. A standardized protocol was followed for PEG preparation, insertion, and aftercare; all patients received a 15 French gastrostomy tube. Follow-up of local and systemic infection and clinical course was continued to postintervention day 10. An aggregate erythema and exudation score > 3 or the presence of pus was taken as indicative of peristomal infection. The pharmacoeconomics of antibiotic use were also examined. RESULTS: In no-prophylaxis patients, wound infection rates were 23.6% on day 4 and 24.5% on day 10 vs. 7.6% (p < 0.05) and 11.4% (p < 0.05), respectively, in prophylaxis patients. Results were disproportionally better in tumor patients in comparison with neurological patients. Patients systemic infection rates were 11.8% vs. 1.9% in noprophylaxis vs. prophylaxis (p < 0.05), and overall infection rates 36.3% vs. 13.3%, respectively (p < 0.05). Pneumonia was more frequent in patients with underlying neurological disease and reduced in the prophylaxis group. Antibiotic and application costs were similar in both groups (p = 0.400). CONCLUSIONS: Single-dose ceftriaxone 1 g is a effective prophylaxis against local and systemic infection after PEG and should be a part of a standard regimen.

Aged↗
PubMed2000

The pediatrician's role in reducing tobacco exposure in children.

OBJECTIVE: Pediatricians have a unique and important role to play in the prevention and treatment of childhood and adolescent tobacco use, the protection of patients from the harmful effects of environmental tobacco smoke, and the encouragement of smoking cessation among parents. However, because recent research indicates that physician training in tobacco dependence is woefully weak and lacks a model for training, this article constructs a useful approach to this problem. METHODOLOGY: A comprehensive review of the literature served as the basis for the development of a new model for pediatrician training in tobacco dependence. RESULTS: A comprehensive model is presented for training pediatricians in the areas of reducing infant and child exposure to environmental tobacco smoke, preventing youth smoking initiation, and providing smoking cessation assistance for adolescents and parents. CONCLUSIONS: Pediatricians have been called on to play an active role in the antitobacco arena. Because of their unique opportunity to interact with children, adolescents, and parents, pediatricians can and should be antitobacco interventionists. For this to occur, however, additional guidance should be provided to pediatricians during their training to better prepare them to carry out effective assessment and intervention practices. smoking initiation, smoking prevention, smoking cessation, environmental tobacco smoke, pediatricians.

Adolescent↗
PubMed1999

Self-assessment of physical sexual maturation in boys and girls with delayed puberty.

We studied 49 boys and girls with delayed physical sexual maturation during treatment with sex steroids. We found significant agreements, but also some disagreements between physicians' and subjects' Tanner sexual maturity ratings. We found neither effects of treatment with sex steroids nor gender differences, comparing ratings between physicians and patients.

Adolescent↗
PubMed1999

Comparison of laparoscopic and open ventral herniorrhaphy.

The repair of large and/or recurrent ventral hernias is associated with significant complications and a recurrence rate that can be more than 50 per cent. Laparoscopic ventral herniorrhaphy, a recent development, has been shown to be safe and effective in the repair of ventral hernias. This study retrospectively reviews all ventral hernia repairs over a 3-year period, November 1995 through December 1998, at a community-based teaching hospital. The purpose of the study was to compare open and laparoscopic repairs. A total of 253 ventral hernia repairs were performed during this time, 174 open and 79 laparoscopic. The age, weight, and sex distribution was similar for each group. The hernias in the open group averaged 34.1 cm2 in size, and mesh used averaged 47.3 cm2. In the laparoscopic group, the hernia defect averaged 73.0 cm2, and the mesh size averaged 287.4 cm2. Operative time was longer in the open group, 82.0 versus 58.0 minutes. In the open group, there were 38 (21.8%) minor and 8 (4.6%) major complications, compared with 13 (16.5%) minor and 2 (2.5%) major complications in the laparoscopic group. Hospital stay was shorter for the laparoscopic group, 1.7 versus 2.8 days. At an average follow-up of 21 months (range, 2-40 months), there have been 36 recurrences in the open group (20.7%) compared with 2 recurrences in the laparoscopic group (2.5%). In this series, laparoscopic ventral herniorrhaphy compares favorably to open ventral herniorrhaphy with respect to wound complications, hospital stay, operative time, and recurrence rate.

Abdomen↗