Biomedical subjects

John Gaughan

Publications and source records attributed to John Gaughan.

27 records · Page 2Linked to original sources

PubMed2004

Laparoscopic esophagomyotomy for achalasia: does anterior hemifundoplication affect clinical outcome?

OBJECTIVE: To determine whether the addition of anterior hemifundoplication to laparoscopic esophagomyotomy for achalasia yields better clinical outcomes than laparoscopic esophagomyotomy alone. SUMMARY BACKGROUND DATA: Although hemifundoplication may prevent gastroesophageal reflux after esophagomyotomy for achalasia, it may also lead to persistent dysphagia in these patients with esophageal aperistalsis. METHODS: This is a retrospective study of 51 consecutive patients (mean age 47.5 +/- 12.6 years) who had laparoscopic esophagomyotomy for achalasia by our group between August 1995 and January 2001. In 29 patients (57%) an anterior hemifundoplication was added to the esophagomyotomy. In 22 patients (43%), no wrap was added. Patients scored (0 = none; 1 = mild; 2 = moderate; 3 = severe) symptom severity (dysphagia, regurgitation, heartburn, chest pain) preoperatively and postoperatively. Weight gain, use of gastrointestinal (GI) medication, tolerance to food, and patient satisfaction were also assessed. RESULTS: Mean patient follow-up was 33 months, and there were no operative deaths. Four patients were converted to open operation (8%). The wrap and no wrap groups were similar in terms of esophageal dilation, preoperative symptom severity and duration (5.7 +/- 7.1 versus 6.1 +/- 7.0 years), and preoperative weight loss (18 +/- 15 versus 20 +/- 20 pounds). Both groups had similar improvement in symptom grade postoperatively and equivalent satisfaction rates (86%). Postoperative weight gain, GI medication use, and food intolerance was also similar. Postoperatively, patients in the wrap group did not have higher dysphagia scores or lower heartburn scores than the no wrap group. CONCLUSION: The addition of anterior hemifundoplication to esophagomyotomy for achalasia does not improve or worsen clinical results.

Adult↗

PubMed2004

Decreased expression of the CD3zeta chain in T cells infiltrating the synovial membrane of patients with osteoarthritis.

Osteoarthritis (OA) is a heterogeneous disease which rheumatologists consider to be noninflammatory. However, recent studies suggest that, at least in certain patients, OA is an inflammatory disease and that patients often exhibit inflammatory infiltrates in the synovial membranes (SMs) of macrophages and activated T cells expressing proinflammatory cytokines. We report here that the expression of CD3zeta is significantly decreased in T cells infiltrating the SMs of patients with OA. The CD3zeta chain is involved in the T-cell signal transduction cascade, which is initiated by the engagement of the T-cell antigen receptor and which culminates in T-cell activation. Double immunofluorescence of single-cell suspensions derived from the SMs from nine patients with OA revealed significantly increased proportions of CD3epsilon-positive (CD3epsilon+) cells compared with the proportions of CD3zeta-positive (CD3zeta+) T cells (means +/- standard errors of the means, 80.48% +/- 3.92% and 69.02% +/- 6.51%, respectively; P = 0.0096), whereas there were no differences in the proportions of these cells in peripheral blood mononuclear cells (PBMCs) from healthy donors (94.73% +/- 1.39% and 93.79% +/- 1.08%, respectively; not significant). The CD3zeta+ cell/CD3epsilon+ cell ratio was also significantly decreased for T cells from the SMs of patients with OA compared with that for T cells from the PBMCs of healthy donors (0.84 +/- 0.17 and 0.99 +/- 0.01, respectively; P = 0.0302). The proportions of CD3epsilon+ CD3zeta+ cells were lower in the SMs of patients with OA than in the PBMCs of healthy donors (65.04% +/- 6.7% and 90.81% +/- 1.99%, respectively; P = 0.0047). Substantial proportions (about 15%) of CD3epsilon+ CD3zeta-negative (CD3zeta-) and CD3epsilon-negative (CD3epsilon-) CD3zeta- cells were found in the SMs of patients with OA. Amplification of the CD3zeta and CD3delta transcripts from the SMs of patients with OA by reverse transcriptase PCR consistently exhibited stronger bands for CD3delta cDNA than for CD3zeta cDNA The CD3zeta/CD3delta transcript ratio in the SMs of patients with OA was significantly lower than that in PBMCs from healthy controls (P < 0.0001). These results were confirmed by competitive MIMIC PCR. Immunoreactivities for the CD3zeta protein were detected in the SMs of 10 of 19 patients with OA, and they were of various intensities, whereas SMs from all patients were CD3epsilon+ (P = 0.0023). The decreased expression of the CD3zeta transcript and protein in T cells from the SMs of patients with OA relative to that of the CD3epsilon transcript is suggestive of chronic T-cell stimulation and supports the concept of T-cell involvement in OA.

Adult↗

PubMed2004

The effects of high-flow vs low-flow oxygen on exercise in advanced obstructive airways disease.

STUDY OBJECTIVES: Current options to enhance exercise performance in patients with COPD are limited. This study compared the effects of high flows of humidified oxygen to conventional low-flow oxygen (LFO) delivery at rest and during exercise in patients with COPD. DESIGN: Prospective, nonrandomized, nonblinded study. SETTING: Outpatient exercise laboratory. PATIENTS: Ten patients with COPD, stable with no exacerbation, and advanced airflow obstruction (age, 54 +/- 6 years; FEV(1), 23 +/- 6% predicted [mean +/- SD]). INTERVENTIONS: After a period of rest and baseline recordings, patients were asked to exercise on a cycle ergometer for up to 12 min. Exercising was started on LFO first; after another period of rest, the patients repeated exercising using the high-flow oxygen (HFO) system, set at 20 L/min and matched to deliver the same fraction of inspired oxygen (Fio(2)) as that of LFO delivery. MEASUREMENTS AND RESULTS: Work of breathing and ventilatory parameters (tidal volume, respiratory rate, inspiratory time fraction, rapid shallow breathing index, pressure-time product) were measured and obtained from a pulmonary mechanics monitor. Borg dyspnea scores, pulse oximetry, blood gases, vital signs were also recorded and compared between the two delivery modes. Patients were able to exercise longer on high flows (10.0 +/- 2.4 min vs 8.2 +/- 4.3 min) with less dyspnea, better breathing pattern, and lower arterial pressure compared to LFO delivery. In addition, oxygenation was higher while receiving HFO at rest and exercise despite the matching of Fio(2). CONCLUSION: High flows of humidified oxygen improved exercise performance in patients with COPD and severe oxygen dependency, in part by enhancing oxygenation.

Exercise Test↗

PubMed2003

Apoptosis of infiltrating T cells in the central nervous system of mice infected with Theiler's murine encephalomyelitis virus.

Theiler murine encephalomyelitis virus (TMEV), DA strain, induces in susceptible strain of mice a biphasic disease consisting of early acute disease followed by late chronic demyelinating disease. Both phases of the disease are associated with inflammatory infiltrates of the central nervous system (CNS). Late chronic demyelinating disease induced by TMEV serves as an excellent model to study human demyelinating disease, multiple sclerosis. During early acute disease, the virus is partially cleared from the CNS by CD3(+) T cells. These T cells express Fas, FasL, negligible levels of Bcl-2 proteins and undergo activation-induced cell death as determined by TUNEL assay leading to resolution of the inflammatory response. In contrast, during late chronic demyelinating disease, and despite dense perivascular and leptomeningeal infiltrates, only very few cells undergo apoptosis. Mononuclear cells infiltrating the CNS express Bcl-2. It appears that the lack of apoptosis of T cells during late chronic demyelinating disease leads to the accumulation of these cells in the CNS. These cells may play a role in the pathogenesis of the demyelinating disease.

Acute Disease↗

PubMed2003

Is there a seasonal difference in the detection of Trichomonas vaginalis by cervical cytology?

This objective of our study was to determine the prevalence of a Trichomonas vaginalis diagnosis in routine Papanicolaou smears and whether it is seasonal. We reviewed the diagnosis rendered for 93,681 Papanicolaou smears evaluated at a medical school hospital laboratory between 1992 and 1997. The occurrence of a diagnosis of T. vaginalis was analyzed by year, by quarter, and by month using a generalized linear regression model. The prevalence of a T. vaginalis diagnosis during the 6-year study period was 3.1%. The between-month and between-quarter comparisons of prevalence were not statistically different. In the population reported here, the prevalence of a Papanicolaou smear diagnosis of T. vaginalis was low and no seasonal difference in making this diagnosis was identified.

Animals↗

PubMed2003

Identical alpha-chain T-cell receptor transcripts are present on T cells infiltrating coronary arteries of human cardiac allografts with chronic rejection.

Chronic cardiac allograft rejection is characterized by graft arteriopathy and is a major obstacle of graft survival. We investigated T-cell receptor (TCR) alpha-chain transcripts of T cells infiltrating human epicardial coronary arteries from cardiac allografts with chronic rejection. The non-palindromic adaptor-polymerase chain reaction (NPA-PCR) was used to specifically amplify TCR alpha-chain transcripts from five explanted cardiac allografts with chronic rejection. The amplified products were cloned and sequenced to obtain the entire ValphaJalpha region. Immuno-histochemistry was used to identify the mononuclear cell infiltrates in the coronary arteries. All the five coronary artery specimens exhibited large populations of infiltrating mononuclear cells, which were primarily comprised of T cells and macrophages. In three specimens, high proportions ( approximately 80%) of identical alpha-chain TCR transcripts were detected. In peripheral blood mononuclear cells from a healthy individual, alpha-chain TCR transcripts were unique when compared to each other. Endomyocardial biopsies collected from one patient six months before the allograft was explanted, contained identical alpha-chain TCR transcripts to those found to be clonally expanded in the coronary arteries from this patient. These results indicate that T cells infiltrating the epicardial arteries of cardiac allografts with chronic rejection undergo proliferation and clonal expansion in response to a specific antigen, which very likely is an (allo)antigen(s).

Cell Movement↗

PubMed2002

Lead awareness: North Philly Style.

Lead poisoning in children has been associated with reduced intelligence, shortened memory, slowed reaction times, poor hand-eye coordination, and antisocial behavior. The cost to society includes not only medical treatment and special education but also higher high-school drop-out rates, which are associated with crime and low earning potential.

Adult↗

PubMedDate not supplied

Incidence of distal femoral and distal tibial deformities in infantile and adolescent blount disease.

The purpose of this study was to assess distal femoral and tibial deformity in patients with infantile and adolescent Blount disease. This was a retrospective review of patients at the authors' institution diagnosed with Blount disease. Thirty-eight patients (21 in the infantile group and 17 in the adolescent group) met the study criteria. Measurements of the anatomic lateral distal femoral angle (aLDFA), anatomic lateral distal tibial angle (aLDTA), and tibiofemoral angle (TFA) were made from long-leg radiographs. The results of the infantile and adolescent measurements were compared with each other and to a normal database. Intraobserver and interobserver error was determined. The adolescent aLDFA measurements were significantly greater (more varus) than for the infantile group and normal database. The aLDTA (ankle) measurements were not statistically different between the two groups, or from the normal database. Analysis of both intraobserver and interobserver error for the aLDFA and aLDTA showed good reliability.

Abnormalities, Multiple↗

PubMedDate not supplied

An inexpensive ex-vivo porcine laparoscopic Nissen fundoplication training model.

BACKGROUND: We recently implemented the use of an ex-vivo porcine model to teach residents the fundamentals of performing a laparoscopic Nissen fundoplication. METHODS: Residents were trained using intact porcine esophagus, stomach, and spleen placed in a standard video-trainer. They were later asked to complete a survey containing a course evaluation. RESULTS: Sixteen residents (R1-R4) completed the survey. They agreed that (1) the exercise was a valuable use of their limited time, (2) repeating the exercise will be of additional benefit, (3) it will improve their ability to perform or assist in an actual case in the OR, and (4) the surgical principles learned using the model will transfer to other laparoscopic cases. Significant subjective improvements were reported in resident comfort level in assisting in or performing a laparoscopic Nissen fundoplication. CONCLUSIONS: The use of an inexpensive ex-vivo porcine training model increases resident comfort level in performing a Nissen fundoplication in the operating room.

Animals↗