The role of skin-homing T cells in extrinsic atopic dermatitis.

BACKGROUND: T cells that express Cutaneous Lymphocyte-Associated antigen (CLA) have the potential of migrating to the skin, and are hypothesized to play a role in cutaneous atopic disease. AIM: To investigate the immune phenotype and cytokine responses to Der p 1 stimulation of CLA+ T cells in extrinsic atopic dermatitis (EAD). DESIGN: In vitro testing, with controls. METHODS: Peripheral blood mononuclear cells (PBMC) were obtained from EAD patients (n=27) and non-atopic healthy individuals (n=22). Phenotypic analysis of naive, CLA+ and non-CLA+ memory/effector CD4+ and CD8+ T cells used markers of cell activation, differentiation, adhesion, apoptosis and chemokine receptor expression. Cytokine responses in these cells were studied following Der p 1 stimulation. RESULTS: CLA+ T cells from EAD patients expressed significantly higher levels of CD25, HLA-DR, CD38, CD71, CXCR1, CXCR2 and lower levels of bcl2, CCR5, CCR7, CXCR3, and CD62L (p<0.05). DISCUSSION: In EAD patients, CLA+ T cells express increased levels of markers associated with activation, adhesion and apoptosis, show differences in the level of expression of differentiation markers and display a distinct chemokine receptor preference, compared with cells from healthy controls. These data suggest a significant role for CLA+ T cells in the pathogenesis of cutaneous atopic disease.

Reliability of echocardiographic measurements of myocardial perfusion using commercially produced sonicated serum albumin (Albunex).

OBJECTIVES: The purpose of this study was to assess the reproducibility and pitfalls of intracoronary and aortic root sonicated albumin injections, using time-intensity curves, in a large sample of normal dogs. BACKGROUND: The utility of a new myocardial contrast echocardiographic agent, sonicated serum albumin (Albunex), is currently under investigation. However, the reproducibility, injection techniques and general pitfalls of this contrast agent have not been well characterized. METHODS: We administered sequential intracoronary and aortic root injections (518 injections) of sonicated albumin in 25 closed chest normal dogs to measure the effectiveness and reproducibility of this product. Time-intensity curves, as a measure of myocardial perfusion, were derived and quantified using an on-line videodensitometric analysis system and two-dimensional echocardiography. Measurements included peak intensity, area under the curve, half-time of descent, alpha-parameter and transit time within a 31- x 31-pixel "region of interest" in the anterior septum. Analyses provided 80% power and a type I error protection of 95%. RESULTS: The best reproducibility of the variables was half-time of descent for aortic root injections (coefficient of variation [CV] 20%) and peak intensity for intracoronary injections (CV 25%), whereas aortic root area under the curve showed the most variability (CV 41%). Analysis of variance for repeated measures of serial intracoronary and aortic root injections showed no significant systematic variability within subjects for the measured variables. In a comparison between intracoronary and aortic root injection sites, paired t tests showed no significant difference for mean values between these two techniques. There was also no statistically significant difference between manual versus power intracoronary injections. Finally, there was no significant difference among three injection rates (1, 2 and 3 ml/s) in paired intracoronary injections, nor was there a difference among injection rates in paired aortic root injections, except for a lower peak intensity with a 1-ml/s injection rate compared with a 2-ml/s injection rate (p = 0.01). Potential pitfalls include preparation of sonicated albumin, delivery techniques and measurement variables. CONCLUSIONS: We conclude that the results of serial injections of sonicated albumin show no systemic change or trend in normal dogs. Both intracoronary and aortic root injections at standard injection rates by hand or power injector can be used to quantify time-intensity curves, as measure of myocardial perfusion, with similar variability ranging from 20% to 41%. These results are important in the human model, especially after coronary interventions.

Effects of mitral regurgitation on pulmonary venous flow and left atrial pressure: an intraoperative transesophageal echocardiographic study.

OBJECTIVES AND BACKGROUND: Pulmonary venous flows recorded by pulsed wave Doppler transesophageal echocardiography examination can be used to assess the severity of mitral regurgitation. Pulmonary venous flows are also related to left atrial pressures; however, the determinants of these flows have yet to be characterized in the presence of mitral regurgitation. METHODS: We simultaneously recorded intraoperative pulmonary venous flows by transesophageal echocardiography and left atrial pressures by direct left atrial puncture in 16 patients with different grades of mitral regurgitation: 2+ (n = 5), 3+ (n = 4) and 4+ (n = 7). Pulmonary venous peak systolic and diastolic flow velocities and peak reversed systolic flow velocities were compared with left atrial pressure a and v waves, a-x and v-y descent values and left atrial volumes. RESULTS: Pulmonary venous systolic to diastolic flow ratios correlated with decreases in left atrial pressure a/v ratios and with increases in the v waves of patients with higher grades of mitral regurgitation. Univariate analysis revealed that the best determinants of the pulmonary venous systolic to diastolic flow ratio were the left atrial pressure v wave (r = -0.76), the v-y descent value (r = -0.73) and the a/v ratio (r = 0.71). Lower correlations were found for left atrial end-systolic (r = -0.48) and end-diastolic (r = -0.42) volumes. Reversed systolic flow was present in patients with 4+ mitral regurgitation, despite left atrial enlargement. CONCLUSIONS: Pulmonary venous flow can be used to assess the severity of mitral regurgitation and reflects the effects of mitral regurgitation severity on the left atrial pressure a and v waves.

Adenovirus polymerase chain reaction assay for rapid diagnosis of conjunctivitis.

PURPOSE: To evaluate newly designed primers in a polymerase chain reaction (PCR) for the detection of adenovirus DNA in conjunctival swabs. METHODS: Oligonucleotides were derived from the adenovirus hexon gene and modified such that a maximum of only two mismatches occurred with adenovirus types 2 through 5, 7, and 16. Specificity was determined against adenovirus types 2 through 4, 7, 8 through 11, 14, 19, 37, 40, and 41 and from non-adenoviral DNA and the sensitivity by PCR amplification of purified adenovirus type 2 DNA. The assay was compared retrospectively with cell culture and a PCR with different primers on 59 stored conjunctival swab samples. The new PCR also was used prospectively in comparison with cell culture on 2743 conjunctival swabs. RESULTS: The 140-bp product was amplified from all the adenovirus serotypes tested except types 40 and 41, which have not been isolated from the eye. There were no amplified products from the non-adenoviral DNA tested. With adenovirus type 2 DNA, despite two deliberate mismatches, 40 copies of the target were detectable after PCR and ethidium bromide-staining. In the retrospective study, 51 of 55 (92.7%) were positive by this new PCR compared with 42 of 55 (76.4%) by the older PCR and 40 of 55 (72.7%) by cell culture. In the prospective study, the new PCR detected 386 of 415 (93%) adenovirus-positive specimens compared with 248 of 415 (59.8%) by cell culture. Of 167 specimens positive for herpes simplex virus by cell culture, none were positive by the adenovirus PCR. CONCLUSIONS: PCR with the newly designed primers shows a much increased sensitivity over cell culture and previous PCRs for the detection of adenoviruses in conjunctival swabs.

Effects of mitral stenosis on pulmonary venous flow as measured by Doppler transesophageal echocardiography.

Pulmonary venous flow as assessed by transesophageal echocardiography (TEE) is influenced by changes in left atrial pressure and function. In mitral stenosis (MS), normal left atrial hemodynamics are altered because there is a prolonged decay in diastolic pressure from the left atrium to the left ventricle and atrial function may be altered because of atrial fibrillation. To assess the effect of the prolonged atrial diastolic pressure decay caused by MS on pulmonary venous flow, we studied 27 patients with MS (mitral valve range 0.7 to 2.4 cm2) by pulsed-wave Doppler TEE of the left or right upper pulmonary vein, and compared results with those of 13 normal subjects. Of the 27 subjects with MS, 61% showed a blunted systolic flow pattern and 39% showed a normal flow pattern with greater systolic to diastolic flow ratio. Patients with atrial fibrillation had a predominantly blunted pattern, whereas patients with normal sinus rhythm exhibited both blunted and normal flow patterns. Patients with MS had a lower pulmonary venous peak systolic flow velocity and a longer diastolic pressure halftime than control subjects. Pulmonary venous peak systolic flow velocity was significantly decreased in the presence of atrial fibrillation (p = 0.004). The mitral valve pressure halftime significantly correlated with pulmonary venous diastolic pressure halftime (r = 0.54; p = 0.004) mitral valve area (r = -0.46; p = 0.02). In conclusion, it was found that MS alters pulmonary venous flow patterns, showing a decreased pulmonary venous systolic flow and a prolonged diastolic flow, which may be useful in assessing the hemodynamics of MS.

An immune dot-blot technique for the diagnosis of ocular adenovirus infection.

The development of a monoclonal antibody based radio-immune dot-blot technique (IDBT) for the rapid detection of adenovirus is described. 718 conjunctival swabs from patients with acute keratoconjunctivitis were examined by conventional cell culture isolation techniques and IDBT. IDBT identified adenovirus in 64 of 75 culture positive samples and also in a further 34 culture negative samples [Sensitivity (IDBT versus culture) 85.3%; Specificity 92.2%]. IDBT is considered to be a simple, clinically relevant, technique for the rapid identification of adenovirus infection of the eye.

Multiplex polymerase chain reaction for adenovirus and herpes simplex virus in eye swabs.

Adenoviruses and herpes simplex virus (HSV) can cause clinically indistinguishable episodes of acute eye disease. Adenovirus infection is associated with nosocomial outbreaks and HSV may result in episodes of recurrent ocular inflammation. In a comparison of multiplex PCR for the two viral DNAs and virus isolation in cell culture, identical results were obtained for 18 of 20 specimens (positive for adenovirus in 5, HSV in 5, and negative in 8). One specimen was falsely negative for each viral DNA. Inclusion of human beta-globin primers in the adenovirus-HSV reaction was precluded by a consequential 10--100-fold reduction in sensitivity for the two viral targets and by the failure of beta-globin DNA amplification at the annealing temperature (45 degrees C) required to ensure detection of adenoviruses of serotypes 7 and 11 with the selected adenovirus primers. A single-target beta-globin PCR gave positive results with 19 of the 20 specimens prepared by treatment with proteinase K lysis buffer, indicating the effectiveness of this simple DNA extraction procedure. Nonetheless, the availability of effective antiviral therapy for HSV made monitoring for extraction failure using human primers crucial to avoid false-negative results for HSV DNA. Adenovirus-HSV PCR has considerable potential for the rapid diagnosis of viral eye disease particularly if beta-globin primers can be included in the reaction.

The effect of technical factors on the quality of pulmonary venous flow from the transverse and longitudinal imaging planes with transesophageal echocardiography.

Right and left upper pulmonary venous flow is usually assessed with monoplane transesophageal echocardiography (TEE) in the transverse imaging plane. Pulmonary venous flow in the transverse imaging plane may be relatively difficult to record because of the larger angle between the pulmonary vein and the transducer beam. To compare the quality of echocardiographically derived Doppler flows of the right and left upper pulmonary veins between the longitudinal and transverse imaging planes with TEE, we performed pulsed-wave Doppler TEE of both upper pulmonary veins in transverse and longitudinal imaging planes in 36 patients with various diseases. We also recorded a quality index for each flow profile and the angle between the transducer beam and the pulmonary vein. The quality index of the left pulmonary venous flow assessed with the longitudinal and transverse imaging planes was similar in 35 (95%) of 36 patients, whereas the longitudinal imaging plane was superior to the transverse plane in one patient (3%). In contrast, the quality index of the right pulmonary venous flow assessed with the longitudinal and transverse imaging planes was similar in only 19 (53%) of 36 patients, whereas in 17 patients (47%) the longitudinal imaging plane was superior to the transverse imaging plane. The quality index had a significant effect on the Doppler flow recordings; suboptimal-quality flow recordings significantly underestimated the pulmonary venous diastolic flow integrals. The left atrium was larger in those patients with unobtainable flows than in those patients with exclusively obtainable flows (p < 0.001). The angle between the sample volume and the right pulmonary vein was larger in the transverse imaging plane than in the longitudinal plane (p < 0.001). In conclusion, the longitudinal imaging plane is generally superior to the transverse imaging plane for assessing right pulmonary venous flow and is recommended for performing a comprehensive assessment of pulmonary venous flow. The ability to obtain quality images and accurate assessment of flow may be related to the size of the left atrium and angle of the pulmonary vein.

Importance of sampling both pulmonary veins in grading mitral regurgitation by transesophageal echocardiography.

Pulmonary venous flow patterns have been used to assess severity of mitral regurgitation; however, the issue of which pulmonary veins to sample has not been determined. We performed pulsed wave Doppler transesophageal echocardiography of both the left and right upper pulmonary veins in 80 patients who had mitral regurgitation determined by independent transesophageal echocardiography color flow mapping. Pulmonary venous flow patterns, peak systolic and diastolic flow, and the presence of reversed systolic flow were compared between the left and right pulmonary veins for each grade of mitral regurgitation. Flow patterns were discordant in 20 (25%) of the 80 patients. Of the 43 patients with 4+ mitral regurgitation, there was discordant flow in 16 (37%) of the patients with mainly reversed systolic flow in the right upper vein, while there was blunted or normal systolic flow in the left upper vein. Of the 16 patients with discordant flows, 14 had eccentric jets, mainly anteromedial jets. We conclude that if discordant flow can occur in 25% of patients with mitral regurgitation and in 37% of patients with 4+ mitral regurgitation, then both pulmonary veins must be evaluated when assessing the severity of mitral regurgitation with pulsed wave Doppler transesophageal echocardiography.

Polymerase chain reaction for rapid diagnosis of respiratory adenovirus infection.

Endemic (type 1, 2, 5 and 6) and epidemic (type 3, 4 and 7) respiratory adenovirus infections are associated with upper respiratory tract symptoms, pharyngoconjunctival fever, and pneumonia. Improved methods of diagnosis are needed, particularly in immunocompromized patients. We examined 93 throat swabs or nasopharyngeal aspirates from patients with acute respiratory disease using virus isolation and an adenovirus-specific polymerase chain reaction (PCR) based on consensus primers H1 and H2 derived from the hexon region DNA sequences of serotypes 2 and 5. Specimens which yielded viruses other than adenovirus in cell culture (n = 23) or which were negative for infectious viruses (n = 25) were negative in the PCR. The sensitivity of DNA amplification was 76% (34/45) in comparison with virus culture, being markedly lower with subgenus B (types 3 and 7) strains than with subgenus C (type 1, 2, 5 and 6) isolates (8/16 (50%)) vs. 26/28 (93%). P = 0.004) despite the use of a low annealing temperature to maximize detection of adenoviruses belonging to subgenera other than C. Of the 11 samples falsely negative in a single-round PCR but yielding adenovirus type 1 (n = 1), type 2 (n = 1). type 3 (n = 7), type 7 (n = 1), or untyped isolates (n = 1) in cell culture, nine (82%) gave positive results after nested DNA amplification. Possible approaches to further improving the performance of adenovirus PCR with respiratory specimens are discussed.

The polymerase chain reaction for detecting adenovirus DNA in formalin-fixed, paraffin-embedded tissue obtained post mortem.

The polymerase chain reaction (PCR) was used to detect adenovirus DNA in formalin-fixed, paraffin-embedded tissue obtained post mortem. Adenovirus DNA was successfully amplified from specimens of lung and liver from two patients with disseminated adenovirus infection confirmed by virus isolation, electron microscopy and/or immunohistochemistry. Negative results were obtained for specimens of lung from two patients with cytomegalovirus pneumonia. The specificity of the adenovirus PCR was confirmed by means of a digoxigenin-labelled probe generated in a separate PCR. Detection of viral nucleic acid by PCR in tissues obtained post mortem has considerable diagnostic potential.

Meningo-encephalitis caused by Coxsackievirus group B type 2. Diagnosis confirmed by measuring intrathecal antibody.

We describe a case of meningo-encephalitis caused by Coxsackievirus group B type 2. Diagnosis was suggested by isolation of virus from faeces and high titres of serum antibody in which Coxsackie virus B2 specific IgM antibody was detected. Evidence of intrathecal production of antibody confirmed the diagnosis.

Fatal disseminated adenovirus type 2 infection following bone marrow transplantation for Hurler's syndrome: a primary infection.

A 5-month-old girl given an allogeneic bone marrow transplant for Hurler's syndrome succumbed to fatal pneumonia 5 weeks after the transplant. Adenovirus type 2 was isolated from her urine before she died. Immunoperoxidase and electron microscopical studies of liver and lungs post mortem confirmed a disseminated adenovirus infection. The serological findings and the patient's young age suggested that the infection was a primary one. The importance of considering exogenous sources of adenovirus infection in bone marrow transplant recipients is discussed.

Detection of male genital infection with Chlamydia trachomatis and Neisseria gonorrhoeae using an automated multiplex PCR system (Cobas Amplicor).

We evaluated Cobas Amplicor, a highly automated polymerase chain reaction (PCR) system, to test first-void urine (FVU) and urethral swab specimens for Chlamydia trachomatis and Neisseria gonorrhoeae in men attending a sexually transmitted infection (STI) clinic. Results were compared against an in-house radioimmune dot blot (DB) test for C. trachomatis and selective culture for N. gonorrhoeae. Three hundred and ninety sets of specimens were obtained from 378 consecutive new and returned-new patients. Gonorrhoea prevalence was 9.49%, with no significant difference in sensitivity or specificity between culture and PCR. Chlamydia prevalence was 15.4%, with sensitivities of: DB 55%, PCR of FVU 86.7%, urethral swab PCR 90%. The specificity of PCR on FVU and urethral swabs was 100%. We have shown that Cobas Amplicor PCR is highly sensitive and specific in the diagnosis of chlamydia and gonorrhoea in men attending an STI clinic. Further economic and scientific studies are needed to determine the cost-effectiveness of this technique for screening in primary care settings.

A comparison between bipedal and quadrupedal rats: do bipedal rats actually assume an upright posture?

STUDY DESIGN: A basic science animal investigation. OBJECTIVES: To determine if bipedal rats differ in upright posture compared with quadrupedal rats. SUMMARY OF BACKGROUND DATA: It has been reported that surgically induced bipedalism in the rat leads to habitual upright posture. Based on this finding, bipedal rats have been used to study the changes erect posture induces in bone, ligament, muscle, and intervertebral discs. Previous studies have used direct observation as a means to describe posture. This study is the first to quantify postural differences between bipedal and quadrupedal rats. METHODS: Eleven bipedal rats were created by forelimb and tail amputation within 24 hours of birth. Eleven quadrupedal rats served as controls. Specialized cages were used with infrared sensors, and a computer program measured the total amount of time in the upright stance, the number of stands, and the amount of horizontal movement in the upright stance. Statistical comparisons were made between bipedal and quadrupedal rats hourly and over a 24-hour period of time. RESULTS: Quadrupedal rats assumed an upright posture for a significantly greater amount of time than bipedal rats when monitored over 24 hours (P = 0.016). Quadrupedal and bipedal rats did not differ in the number of stands (P = 0.63) or in the amount of horizontal movement in the upright stance (P = 0.34) over 24 hours. Similar results were obtained when comparing hourly intervals. CONCLUSION: This study quantifiably indicates that bipedal rats do not assume a more erect posture and spend no more time in an upright position compared with quadrupedal rats. The upright posture may not be the cause of some previously reported anatomic changes observed in the bipedal rat.

Morphometric evaluation of the cervico-thoracic junction. Practical considerations for posterior fixation of the spine.

STUDY DESIGN: Linear and angular measurements were performed on 128 vertebrae (16 spines) from C5 to T5. OBJECTIVES: Vertebrae were studied to characterize vertebral shape and size changes in the cervico-thoracic region. SUMMARY OF BACKGROUND DATA: Analysis of vertebral anatomy has been extensive and well characterized. Regions of transitional anatomy necessitate further study due to the often abrupt changes in anatomic relationships. METHODS: Two observers performed linear and angular measurements including pedicle width, height, and length, as well as pedicle-body, pedicle-lamina, lamina-transverse process, and pedicle-lamina angular measurements. Pedicle axis projection on the posterior aspect of the lamina was also calculated. RESULTS: The mean pedicle width ranged from 7.8 mm (T1) to 4.4 mm (T5). The body-pedicle angle decreased > 4 degrees per level in the transverse plane, from 50 degrees (C5) to 11 degrees (T5). The axial projection of the pedicle changed throughout the region (compared with level above) and was significant for T1. CONCLUSIONS: Because of the complexities of the cervico-thoracic junction, additional characterization increases the knowledge of the anatomic relationships in this region.

Anatomic relationships of the cervicothoracic junction.

STUDY DESIGN: This study analyzed the anatomic relationships between bony structures and soft tissues of the cervicothoracic junction. OBJECTIVES: To provide composite reference data for intrasegmental and intersegmental gradients of anatomic variation within the cervical-thoracic junction. SUMMARY OF BACKGROUND DATA: Because the risk of soft tissue damage during posterior spinal stabilization, an understanding of bony and soft tissue changes in the cervicothoracic junction is necessary. METHODS: Three-hundred-twenty-four cross-sectional spinal segments from nine spines were analyzed to characterize cervicothoracic junctional anatomy. RESULTS: There were predictable cranial-to-caudal alterations in both bone and soft tissue anatomy of the cervicothoracic junction. Neural and vascular structures directly anterior to the lateral mass or transverse process and lateral to the pedicle tend to decrease in frequency, whereas measured parameters of the vertebrae increase in size from C5-T3, except for pedicle dimensions that tend to increase at the C7-T1 junction. CONCLUSION: The anatomic changes that occur within the cervicothoracic junction are consistent and predictable, and their recognition should lead to a better appreciation of their clinical implications.

Herpesvirus simplex in chronic human stromal keratitis.

A method is described for the isolation of Herpesvirus simplex (HSV) from corneal discs of patients suffering from chronic stromal keratitis. The discs were removed during penetrating keratoplasty. Virus was successfully isolated from 2 out of 8 discs maintained in vitro.

Recent respiratory and enteric adenovirus infection in children in the Manchester area.

Seventy-three group B adenoviruses (29 type 3 and 44 type 7) identified in a recent community outbreak were analysed with restriction endonucleases. Considerable genetic heterogeneity was identified, particularly amongst the type 3 isolates, but this genome variation could not be correlated with either clinical or epidemiological findings. Group F adenoviruses were found in 132 (4.1%) of 3202 stool specimens from children with gastroenteritis and, after rotaviruses, they were the most common viruses identified. Unlike rotaviruses, these enteric adenoviruses were endemic throughout the 3-year study period and the greatest proportion of infections (47.6%) were found in babies under 6 months old.

Surgical anatomy of the radial nerve in the arm: practical considerations of the branching patterns to the triceps brachii.

Thirty-three cadaveric dissections were performed to identify radial nerve branching patterns to the triceps brachii. Radial innervation of the long head of the triceps originated in the axilla in 88% of the cases and the brachio-axillary angle in 12%. Innervation of the medial head of the triceps originated in the spiral groove in 52% of the cases, the brachio-axillary angle in 39%, and the axilla in 9%. The lateral head was innervated by branches arising in the spiral groove in 70% of the cases, the brachio-axillary angle in 24%, and the axilla in 6%. On average, the radial nerve crossed the midline in the proximal 45% of the arm, 3 cm superior to the level of the deltoid insertion. An intramuscular tendon was present in the medial head of the triceps. The tendon, located medial to the midline of the arm, was seen in all specimens. This tendon serves as an interneural plane with nerve branches descending on either side, but never crossing from one side to the other. Due to the complexity of radial nerve branching, this tendon may be used as a reference plane for longitudinal splitting of the medial head minimizing the risk of nerve damage.