Preoperative CT-Based Three-Dimensional Templating in Robot-Assisted Total Knee Arthroplasty More Accurately Predicts Implant Sizes than Two-Dimensional Templating

Patient dissatisfaction after total knee arthroplasty (TKA) is a concern. Surgical error is a common, avoidable cause of failed TKA. Correct femoral and tibial component sizing improves implant longevity, clinical outcomes, knee balance, and pain scores. We hypothesized that preoperative three-dimensional (3D) templating for robot-assisted TKA (RA-TKA) is more accurate than two-dimensional (2D) digital templating. Prospectively collected data from 31 RA-TKAs were assessed to determine accuracy pertaining to implant sizing and positioning. All cases undergoing RA-TKA undergo preoperative CT-scans as per protocol. Three blinded observers retrospectively templated these knees for TKA using standard radiographs. We compared whether 2D templating was as accurate as CT-guided templating. Postoperative radiographs were then evaluated for sizing and positioning. Intraclass correlation coefficients (ICCs) and the effect of learning curve were assessed. Preoperative femoral component 3D templating and retrospective blinded 2D templating accuracies were 96.6% and 52.9%, respectively (χ ²: 17.965; odds ratio [OR]: 24.957, 3.250-191.661; p < 0.001). Tibial component 3D and 2D templating accuracies were 93.1% and 28.7%, respectively (χ ^2: 36.436; OR: 33.480, 7.400-151.481; p < 0.001). ICC for the three radiograph observers was 0.920 (95% confidence interval [CI]: 0.652-0.890; p < 0.001) for the femur and 0.833 (0.717-0.911; p < 0.001) for the tibia, showing excellent agreement. We conclude that preoperative CT-based templating for RA-TKA more accurately predicts the size of implants compared with traditional 2D digital templating. This may improve operating room efficiency and cost containment.

Proteomic analysis of filaggrin deficiency identifies molecular signatures characteristic of atopic eczema

BACKGROUND

Atopic eczema (AE) is characterized by skin barrier and immune dysfunction. Null mutations in filaggrin (FLG), a key epidermal barrier protein, strongly predispose to AE; however, the precise role of FLG deficiency in AE pathogenesis remains incompletely understood.

OBJECTIVES

We sought to identify global proteomic changes downstream of FLG deficiency in human epidermal living skin-equivalent (LSE) models and validate findings in skin of patients with AE.

METHODS

Differentially expressed proteins from paired control (nontargeting control short hairpin RNA [shNT]) and FLG knockdown (FLG knockdown short hairpin RNA [shFLG]) LSEs were identified by means of proteomic analysis (liquid chromatography-mass spectrometry) and Ingenuity Pathway Analysis. Expression of key targets was validated in independent LSE samples (quantitative RT-PCR and Western blotting) and in normal and AE skin biopsy specimens (immunofluorescence).

RESULTS

Proteomic analysis identified 17 (P ≤ .05) differentially expressed proteins after FLG knockdown, including kallikrein-7 (KLK7; 2.2-fold), cyclophilin A (PPIA; 0.9-fold), and cofilin-1 (CFL1, 1.3-fold). Differential protein expression was confirmed in shNT/shFLG LSEs; however, only KLK7 was transcriptionally dysregulated. Molecular pathways overrepresented after FLG knockdown included inflammation, protease activity, cell structure, and stress. Furthermore, KLK7 (1.8-fold) and PPIA (0.65-fold) proteins were differentially expressed in lesional biopsy specimens from patients with AE relative to normal skin.

CONCLUSIONS

For the first time, we show that loss of FLG in the absence of inflammation is sufficient to alter the expression level of proteins relevant to the pathogenesis of AE. These include proteins regulating inflammatory, proteolytic, and cytoskeletal functions. We identify PPIA as a novel protein with levels that are decreased in clinically active AE skin and show that the characteristic upregulation of KLK7 expression in patients with AE occurs downstream of FLG loss. Importantly, we highlight disconnect between the epidermal proteome and transcriptome, emphasizing the utility of global proteomic studies.

Intraocular use of rituximab

PURPOSE

To evaluate the toxicity of 1 mg of intraocular rituximab and to present a small case-series of patients treated with intravitreal rituximab.

METHODS

Rituximab (1 mg/0.1 ml) was injected in the vitreous of one eye of three Dutch-belted rabbits. Two animals were injected with balanced salt solution as controls. At 1 month the rabbits were killed and the eyes examined by light microscopy. Three patients (five eyes) with intraocular lymphoma were also treated with a 1 mg injection of rituximab.

RESULTS

The treated rabbit eyes and the control eyes showed no light microscopic evidence of ocular toxicity at 1 month following injection. The five human eyes of three patients have shown no evidence of intraocular toxicity with a median follow-up time of 3.6 months (range 2.0-6.4 months). One patient received a total of four injections in the right eye and three injections in the left eye.

CONCLUSION

Intravitreal rituximab at a dose of 1 mg does not appear to cause toxicity in rabbit eyes and in the five eyes of three patients.

Birth resulting from transfer of blastocysts cryopreserved with propanediol after spontaneous hatching

This paper reports the birth of a healthy baby resulting from transfer of blastocysts that were cryopreserved using propanediol after spontaneous hatching. A young infertile couple underwent IVF treatment in the clinic. After several IVF attempts, two births resulted; the first one with fresh embryos in 1996 after three IVF cycles, and the second one in 1999 (after a new IVF cycle in 1998) with frozen blastocysts that had remained cryopreserved in 1.5 mol/l propanediol and 0.1 mol/l sucrose after spontaneous hatching. This report of a healthy baby following transfer of hatched blastocysts frozen in propanediol supports further exploration of this approach.

Squamous cell carcinoma of the eyelids

AIM

To review the clinical features, management, and outcomes of surgical treatment of eyelid squamous cell carcinoma (SCC).

METHODS

A retrospective review of all eyelid SCCs treated between 1992 and 2001.

RESULTS

51 cases were identified in 50 patients. Patient ages ranged from 26 to 93 years, with a mean age of 65 years. 33 patients were male and 17 were female. The lesion was found on the lower lid in 31 cases, upper lid in five cases, lateral canthus in six cases, and medial canthus in nine cases. Perineural invasion was found in four patients, and orbital invasion in three patients. Recurrence occurred in one patient. Treatment was by complete excision with histological confirmation of clear margins. Exenteration was required in three patients. No patients developed lymph node or distant metastases. One patient, who declined treatment, died as a result of the tumour. Mean follow up was 31.1 months.

CONCLUSIONS

Eyelid SCC is a relatively uncommon, but potentially fatal disease. However, if detected early and treated adequately, the prognosis is generally excellent. Treatment by complete excision with histological confirmation of tumour clearance is recommended. Perineural spread is an adverse prognostic sign, which may require postoperative radiotherapy. Orbital invasion is a rare complication but, if recognised early, can be treated effectively with exenteration. Because presentation varies and histological examination is required for accurate diagnosis, any suspicious lesion occurring on the eyelids should be excised or biopsied. All patients with eyelid SCC should be advised of the risk of recurrent or new tumours and encouraged to attend lifelong follow up. Prevention remains of prime importance in minimising the morbidity and mortality of these lesions.

XR3054, structurally related to limonene, is a novel inhibitor of farnesyl protein transferase

In this report, a novel inhibitor of farnesyl protein transferase (FPTase) is described. The compound, XR3054, is structurally similar to farnesol, a component of the reaction in which FPTase catalyses transfer of farnesol pyrophosphate to the CAAX recognition motif on proteins. The compound was selected initially because of its ability to inhibit in vitro farnesylation of CAAX recognition peptides with an IC50 of 50 microM. The farnesylation of p21 ras was reduced in a dose-dependent manner in the presence of XR3054. Similarly XR3054 was able to reduce the anchorage-independent growth of V12 H-ras transformed NIH 3T3 cells in a focus formation assay in soft agar, with an IC50 value of 30 microM, whilst not affecting the anchorage-independent growth of v-raf transformed cells. XR3054 reduced the phosphorylation of p42 mitogen activated protein (MAP) kinase in parental NIH 3T3 cells and V12 H-ras transformed NIH 3T3 cells, but constitutively active v-raf transformed cells showed no reduction in phosphorylation of ERK2 in the presence of XR3054. XR3054 inhibited the proliferation of the prostatic cancer cell lines LnCAP and PC3 and the colon carcinoma SW480 and HT1080 (IC50 values of 12.4, 12.2, 21.4 and 8.8 microM, respectively) but was relatively inactive when tested against a panel of breast carcinoma cell lines. The activity did not relate to the presence of mutant or wild-type ras in the cell lines tested. In conclusion XR3054 inhibits ras farnesylation, MAP kinase activation and anchorage-independent growth in NIH 3T3 transformed with v12 H-ras. Since the antiproliferative effect of the compound is not related to the ras phenotype, XR3054 may also have effects on other cell signalling mechanisms.

Empty follicle syndrome due to human errors: its occurrence in an in-vitro fertilization programme

We report five cases in which no oocytes were retrieved after standard ovarian stimulation for in-vitro fertilization (IVF), and in which it was found that mistakes had been made at the time of human chorionic gonadotrophin (HCG) administration. In all five cases, oocyte retrieval was achieved after injecting HCG, when necessary, and reprogramming aspiration 24-36 h later. A mean of 7+/-3.2 MII oocytes were recovered per patient and 3.2+/-0.8 embryos were transferred. Three clinical pregnancies were obtained, and four healthy infants were born. In our programme, these were the only cases of empty follicle syndrome (EFS) that appeared over a total of 1118 cycles, and were all explained by human error in the administration of HCG. Our experience shows that human error could be considered a significant factor in the aetiology of empty follicle syndrome, and that EFS may be in part avoided by taking simple preventive measures.

[Pregnancy obtained by intracytoplasmic oocyte injection of spermatozoa retrieved from a cryopreserved testicular biopsy]

We have obtained a clinical pregnancy in a 26 year old patient by means of in vitro oocyte fertilization by intracytoplasmic injection of spermatozoa obtained from a cryopreserved testicular biopsy. In a first attempt performed with fresh biopsy material, the woman became pregnant, but the pregnancy ended in a spontaneous abortion. In a second cycle, the spermatozoa were retrieved from a cryopreserved sample saved from the first attempt. Twelve metaphase II oocytes were collected and injected; from these, nine became fertilized, three preembryos were transferred at the eighth-cell stage and the other six were cryopreserved. An ongoing clinical pregnancy was obtained with two gestational sacs.

Analysis of delta-L-alpha-aminoadipyl-L-cysteinyl-D-valine by ion chromatography and pulsed amperometric detection

A novel high-performance liquid chromatography (HPLC) method is presented for the detection and trace level determination of the tripeptide delta-L-alpha-aminoadipyl-L-cysteinyl-D-valine (ACV). The tripeptide, an intermediate in penicillin production, is derived from fungal fermentation. The technique relies on ion-exchange separation of the tripeptide on an anion-exchange column followed by detection by reduction on a gold electrode using pulsed amperometry. The sensitivity of direct determination of ACV is increased by employing pulsed amperometric detection (PAD) over direct ultraviolet detection. Choice of the working electrode and optimisation of electrode potentials was based on cyclic voltammograms recorded for the tripeptide in the mobile phase. A linear regression equation was obtained over the range 0-100 micrograms ml-1. The detection limit in fermentation broths was found to be 0.1 micrograms ml-1 whereas in buffer the detection limit was found to be 10 ng ml-1. A good correlation coefficient was observed when ACV concentrations determined by ion chromatography-PAD were compared with measurements obtained by pre-column derivatisation with fluoromethylorthochloroformate followed by HPLC separation on a reversed-phase C18 silica column with UV detection. The procedure has been applied to the measurement of natural levels of ACV in fermentation broths of selected strains of Aspergillus nidulans and Penicillin chrysogenum.