Response to strict and liberalized specific carbohydrate diet in pediatric Crohn’s disease

AIM: To investigate the specific carbohydrate diet(SCD) as nutritional therapy for maintenance of remission in pediatric Crohn's disease(CD). METHODS: Retrospective chart review was conducted in 11 pediatric patients with CD who initiated the SCD as therapy at time of diagnosis or flare. Two groups defined as SCD simple(diet alone, antibiotics or 5-ASA) or SCD with immunomodulators(corticosteroids and/or stable thiopurine dosing) were followed for one year and compared on disease characteristics, laboratory values and anthropometrics.RESULTS: The mean age at start of the SCD was 11.8 ± 3.0 years(range 6.6-17.6 years) with five patients starting the SCD within 5 wk of diagnosis. Three patients maintained a strict SCD diet for the study period and the mean time for liberalization was 7.7 ± 4.0 mo(range 1-12) for the remaining patients. In both groups, hematocrit, albumin and ESR values improved while on strict SCD and appeared stable after liberalization(P-value 0.006, 0.002, 0.002 respectively). The majority of children gained in weight and height percentile while on strict SCD, with small loss in weight percentile documented with liberalization. CONCLUSION: Disease control may be attainable with the SCD in pediatric CD. Further studies are needed to assess adherence, impact on mucosal healing and growth.     

Matrix metalloproteinases and their natural inhibitors in fibrovascular membranes of proliferative diabetic retinopathy

AIM: To examine epiretinal membranes of proliferative diabetic retinopathy (PDR) for the presence of selective matrix metalloproteinases (MMPs) and their natural inhibitors (TIMPs), in order to determine whether neovascularisation and fibrosis, characteristic of this complication of diabetes mellitus, are associated with specific anomalies of MMP or TIMP expression. METHODS: The presence of selected MMPs and TIMPs was investigated in 24 fibrovascular epiretinal membranes of PDR, and the findings compared with that observed in 21 avascular epiretinal membranes of proliferative vitreoretinopathy (PVR) and five normal retinas. Specimens were examined for deposition of interstitial collagenase (MMP-1), stromelysin-1 (MMP-3), gelatinase A (MMP-2), gelatinase B (MMP-9), and three tissue inhibitors of metalloproteinases (TIMP-1, TIMP-2, and TIMP-3). RESULTS: The results showed that unlike normal retina, which constitutively expresses MMP-1 and TIMP-2, a large proportion of PDR membranes (> 62%) stained for MMP-1, MMP-2, MMP-3, MMP-9, TIMP-1, TIMP-2, and TIMP-3. There were no differences in the expression of these molecules when compared with PVR membranes. A characteristic staining for MMP-9 was observed within the perivascular matrix of PDR membranes, and there was a significant increase in TIMP-2 expression by PDR membranes (p= 0.036) when compared with PVR membranes. CONCLUSIONS: The findings that MMPs involved in degradation of fibrovascular tissue matrix, as well as TIMP-1 and TIMP-2, are found in a large proportion of PDR membranes, and that their expression does not differ from that of PVR membranes, suggest the existence of common pathways of extracellular matrix degradation in pathological processes leading to retinal neovascularisation and fibrosis.     

Wound healing modulation after glaucoma surgery

Recent developments in molecular and cell biology have made a major impact on our understanding of the wound healing process and its modification. In this article, the spectrum of therapies that are either currently available or have potential application as modulators of the scarring response following glaucoma surgery are reviewed. Refinement of existing antimetabolite regimens can improve surgical results, especially in carefully selected patient groups. However, the most promising new approach appears to be using molecular-based therapies, such as fully human neutralizing monoclonal antibodies, designed to target specific molecules in the scarring response. Such strategies ultimately offer the potential of safer, more specific, focal, and titratable treatment, with far-reaching clinical applications.     

A randomised,controlled trial of cemented versus cementless press-fit condylar total knee replacement. Ten-year survival analysis

We have carried out a long-term survival analysis of a prospective, randomised trial comparing cemented with cementless fixation of press-fit condylar primary total knee replacements. A consecutive series of 501 replacements received either cemented (219 patients, 277 implants) or cementless (177 patients, 224 implants) fixation. The patients were contacted at a mean follow-up of 7.4 years (2.7 to 13.0) to establish the rate of survival of the implant. The ten-year survival was compared using life-table and Cox's proportional hazard analysis. No patient was lost to follow-up. The survival at ten years was 95.3% (95% CI 90.3 to 97.8) and 95.6% (95% CI 89.5 to 98.2) in the cemented and cementless groups, respectively. The hazard ratio for failure in cemented compared with cementless prostheses was 0.97 (95% CI 0.36 to 2.6). A comparison of the clinical outcome at ten years in 80 knees showed no difference between the two groups. The survival of the press-fit condylar total knee replacement at ten years is good irrespective of the method of fixation and brings into question the use of more expensive cementless implants.     

In vivo production of interferon beta by human Tenon's fibroblasts; a possible mediator for the development of chronic conjunctival inflammation

BACKGROUND: Chronic inflammation may develop from failure of the immune system to deactivate itself during resolution of the wound healing response, and is recognised as a major risk factor for trabeculectomy failure. Fibroblast/T cell interactions may contribute to aggressive scarring. Our previous research showed that in vitro human Tenon's fibroblast produced interferon beta was responsible for preventing T cell apoptosis, suggesting that this interaction could contribute to the development of chronic inflammation. METHODS: Immunohistological techniques were used to investigate the in vivo components of this particular fibroblast/T cell interaction in conjunctival biopsies from glaucoma patients undergoing filtration surgery. RESULTS: Fibroblast produced interferon beta and T lymphocytes were identified in human conjunctiva. CONCLUSION: The components of fibroblast mediated prevention of T cell apoptosis were identified in vivo, suggesting that the development of this interaction is possible and that it may contribute to the development of chronic inflammation and excessive scarring.     

The corneal thickness and intraocular pressure story: where are we now?

A review of the current literature was conducted regarding the effect of corneal thickness on the diagnosis of glaucoma, and the influence of excimer laser refractive surgery on intraocular pressure (IOP) measurement with Goldmann applanation tonometry. In general, normals and primary open angle glaucoma patients have a similar distribution of corneal thickness; however, there is a wide variation, ranging from 427 to 716 micro m. Normal tension glaucoma patients have a tendency towards thinner corneas than normals; however, there is an overlap of thickness measurements of more than two-thirds in 95% of patients. There is a trend for ocular hypertensives to have thicker corneas than normals, but again there is an overlap of about one-third in 95% of patients. The general trend after excimer laser refractive surgery is for a decrease in IOP, with a mean fall in IOP measured of 0.63 mmHg per dioptre correction. There is, however, a large scatter of values with some patients having the same or lower IOP post-laser, but with other patients measuring higher pressures. Corneal thickness can influence IOP measurement by Goldmann applanation tonometry; however, the magnitude of the effect is subject to much individual variation.     

Randomized,double-blind comparison of different inspired oxygen fractions during general anaesthesia for Caesarean section

Background. The optimal inspired oxygen fraction FI_O2 for fetaloxygenation during general anaesthesia for Caesarean sectionis not known. Methods. We randomized patients having elective Caesarean sectionto receive one of the following: FI_O2 0.3, FI_N2O 0.7 and end-tidalsevoflurane 0.6% (Group 30, n=20); FI_O2 0.5, FI_N2O 0.5 and end-tidalsevoflurane 1.0% (Group 50, n=20), or FI_O2 1.0 and end-tidalsevoflurane 2.0% (Group 100, n=20) until delivery. Neonataloutcome was compared biochemically and clinically. Results. At delivery, for umbilical venous blood, mean PO₂ wasgreater in Group 100 (7.6 (SD 3.7) kPa) compared with both Group30 (4.0 (1.1) kPa, P<0.0001) and Group 50 (4.7 (0.9) kPa,P=0.002) and oxygen content was greater in Group 100 (17.2 (1.6)ml dl^–1) compared with both Group 30 (12.8 (3.6) ml dl^–1,P=0.0001) and Group 50 (13.8 (2.6) ml dl^–1, P=0.0001).For umbilical arterial blood, PO₂ was greater in Group 100 (3.2(0.4) kPa) compared with Group 30 (2.4 (0.7) kPa, P=0.003),and in Group 50 (2.9 (0.8) kPa) compared with Group 30 (2.4(0.7) kPa, P=0.04); oxygen content was greater in Group 100(10.8 (3.5) ml dl^–1) than in Group 30 (7.0 (3.0) ml dl^–1,P<0.01). Apgar scores, neonatal neurologic and adaptive capacityscores, and maternal arterial plasma concentrations of epinephrineand norepinephrine before induction and at delivery were similaramong groups. No patient reported intraoperative awareness. Conclusions. Use of FI_O2 1.0 during general anaesthesia forelective Caesarean section increased fetal oxygenation. Br J Anaesth 2002; 89: 556–61     

Uptake of 111In-Z2D3 on SPECT imaging in a swine model of coronary stent restenosis correlated with cell proliferation.

Small targets such as cell proliferation in the coronary arteries may potentially be detected with single-photon imaging using high-radiotracer-specific activity. We hypothesized that an antibody linked to polymers to increase specific radioactivity can be visualized on SPECT images and that counts in the target will correlate with the strength of the biologic signal. METHODS: Twenty-four stents were placed using the balloon overexpansion technique in the coronary arteries of 14 juvenile domestic swine. One week later, the animals received 74 MBq of (111)In-diethylenetriaminepentaacetic acid-polylysine Z2D3-F(ab')(2), and SPECT imaging was performed at 24 h. The coronary vessels were removed, and the stented vessels were processed with plastic embedding and sectioning. Medial and neointimal areas, percentage of vessel stenosis, and cell proliferation indices were quantified using a 5-bromo-2-deoxyuridine (BrdU) labeling index. Reconstructed SPECT images were interpreted for tracer uptake in coronary vessels. RESULTS: Sixteen of the vessels were positive on SPECT imaging and 10 were negative. The percentage injected dose was 0.85 +/- 0.28 x 10(-3) in scan-positive vessels and 0.34 +/- 0.11 x 10(-3) in scan-negative vessels (P < 0.001). The medial-plus-neointimal proliferative index was 42 +/- 11 in scan-positive vessels and 11 +/- 11 in scan-negative vessels (P < 0.0001). The percentage stenoses were 21% +/- 22% versus 19% +/- 15% (not statistically significant). When individual values for the stented-to-control vessel counts were plotted against BrdU labeling index, a significant relationship was found (r(2) = 0.441; P = 0.0014). CONCLUSION: These data indicate that small targets relevant to human coronary vascular disease may be detected using polymer-modified radiolabeled antibodies.