Short-term results of the uncemented triathlon total knee arthroplasty: a large cohort single-centre comparative study.

BACKGROUND: The purpose of this study is to assess the short-term survivorship of a new uncemented TKA design in a high-volume centre to evaluate the safety of this design prior to widespread adoption. METHODS: We performed a retrospective cohort study of all primary TKAs (cemented and uncemented) between May 2018 and May 2019. Primary outcome variables included aseptic revision, all-cause revision, time to revision, operative time and radiological outcomes. Predictor variables considered included age, gender, BMI, ASA, implant type (cruciate-retaining, posterior-stabilised or totally-stabilised) and the use of cemented or uncemented implants. RESULTS: There were 300 cemented TKAs and 249 uncemented TKAs (Triathlon, Stryker Inc., Mahwah, NJ) implanted. The mean follow-up for all cases was 31.6 months (minimum follow-up 2 years). Of the entire 549 implants only 4 were revised. Two of these were for infection, 1 was for patellar maltracking and 1 was for knee stiffness. All 4 revisions occurred in the cemented cohort. The aseptic revision rate in the cemented cohort was 0.7% compared to 0.0% in the uncemented cohort (p = 0.298). Operative times were significantly reduced in the uncemented cohort from 57.9 to 51.7 min (p < 0.001). There were 8/300 (2.6%) patients with RLLs in the cemented cohort and 4/249 (1.6%) patients with RLLs in the uncemented cohort (p = 0.56). CONCLUSION: The uncemented Triathlon TKA demonstrates excellent survivorship at short-term follow-up when compared to the cemented Triathlon TKA, thus eliminating any potential clinical concerns with this novel implant in the early post-operative phase.

Transmission of human immunodeficiency virus by heterosexual contact with reference to antenatal screening.

Twenty-seven women all of childbearing age, eight of whom were pregnant, were identified as human immunodeficiency virus (HIV-1) antibody positive in the genitourinary medicine clinics of East Riverside up to March 1987. Of these 27 women 11 had acquired the virus by heterosexual contact. Between 1 March 1987 and 29 February 1988, all 1328 women attending the antenatal clinic were offered an HIV screening test, 982 accepted and the other 346 declined to be tested. Two of the 982 tested women were found to be HIV-1 antibody positive. Two other pregnant HIV-1-positive women were identified during this time, one was tested in the genitourinary medicine clinic and the other whilst an in-patient for drug withdrawal. All except one of the 12 HIV-1-antibody-positive pregnant women were in known high-risk groups. In addition up to March 1988, 32 heterosexual men were identified as HIV-1 antibody positive and 22 of these were intravenous drug abusers. If the present trend continues, more women will become infected, often unaware that they are at risk and this may not be detected unless HIV testing is offered to all pregnant women and widely accepted. Decisions on local policy should be based on the available estimates of prevalence of HIV infection in that community.

Enzymatic and chemical modifications of lipopeptide antibiotic A21978C: the synthesis and evaluation of daptomycin (LY146032).

The novel lipopeptide antibiotic A21978C complex is active against Gram-positive organisms. This complex consists of a common peptide nucleus with various lipid acyl groups at the N-terminus characteristic of each individual factor. The fatty acid acyl group is removed by incubation of the A21978C complex with Actinoplanes utahensis to give the peptide nucleus. This peptide nucleus has the same amino acid sequence as A21978C. New analogs of A21978C were synthesized by acylation of the N-terminus of a tert-butoxycarbonyl (tert-BOC)-protected nucleus and subsequent deprotection. 1H NMR showed that the newly introduced acyl group was at the desired N-terminus. Three major groups of analogs were synthesized bearing fatty acid acyl, amino-aroyl and extended peptide side chains. Each analog was evaluated for antimicrobial activity and acute toxicity. Of these analogs, the n-decanoyl analog of A21978C (LY146032) gave the best survival in the mouse acute toxicity test at a high dose of 1,000 mg/kg, iv and was chosen for further study. This analog has been named daptomycin.

Squamous carcinoma of the anus in young homosexual men with T helper cell depletion.

Two cases of squamous carcinoma of the anus in white homosexual men aged 36 and 47 years are reported, each with a short history of rapidly enlarging perianal lesions. Immunological studies showed that both men had pronounced T helper lymphocyte depletion, and antibody to human T cell lymphotropic virus type III (HTLV-III) was detected in both patients. In addition one patient had a long history of wart virus infection of the anal canal. The diminished cellular immunity associated with HTLV-III may have been responsible for the development of the squamous carcinoma, either directly or by its association with human papilloma virus infection.

In vitro and in vivo anti-Candida activity and toxicology of LY121019.

LY121019 (N-p-octyloxybenzoylechinocandin B nucleus) is a semisynthetic antifungal antibiotic that possesses potent anti-Candida activity. The MIC50 and the MIC90 for both LY121019 and amphotericin B were 0.625 and 1.25 micrograms/ml, respectively. Only an 8-fold increase in the MIC against C. albicans occurred during 34-day exposure to subinhibitory concentrations indicating that LY121019 has a low potential for causing resistance development. Scanning electron microscopic studies revealed that LY121019 caused severe damage to the C. albicans cell. The ED50's for LY121019 and amphotericin B administered parenterally to mice were 7.4 and 2.5 mg/kg, respectively. Parenterally administered LY121019 at doses of 6.25 mg/kg significantly reduced the recovery of C. albicans from infected mouse kidneys. Orally administered 50 and 100 mg/kg doses of LY121019 were effective in eliminating C. albicans from the gastrointestinal tract of infected mice. Topical application of 5% LY121019 was as effective as 3% nystatin in the treatment of superficial C. albicans infections. Local administration of LY121019, nystatin, or miconazole was effective against rat vaginal candidiasis. LY121019 was administered intravenously to dogs at doses up to 100 mg/kg/day, 5 days a week for 3 months; all dogs survived. Compound related effects included a histamine-like reaction, increased serum alkaline phosphatase and SGPT, fatty vacuolization of the liver, and some tissue damage at the injection site. The no effect dose in dog was 10 mg/kg. LY121019 had no more than 1/20 the toxicity of amphotericin B in the dog.

Comparative toxicology of monensin sodium in laboratory animals.

The toxicology of monensin has been studied in several laboratory animal species. There was considerable species variation in acute oral LD50 values. The consistent signs of acute toxicity were: anorexia, hypoactivity, skeletal muscle weakness, ataxia, diarrhea, decreased weight gain and delayed deaths. The 3-mo study in rats fed diets containing 0, 50, 150 or 500 ppm monensin resulted in no effects at the lowest dose level, slight reduction of body weight gain in the middle-dose group and severe depression in body weight gain, skeletal and cardiac lesions, and deaths in the highest dose group. The 3-mo study in dogs given daily oral doses of 0, 5, 15 or 50 mg/kg monensin resulted in no effects at the lowest dose level. Dogs in the 15 and 50 mg/kg groups developed, during test wk 1 to 4, anorexia, weakness, ataxia, labored respiration, body weight loss, increased serum muscle enzyme values, severe skeletal muscle degeneration and necrosis with less severe heart lesions and deaths. Mice fed diets containing 0, 37.5, 75, 150 or 300 ppm monensin for 3 mo had reduced body weight gain in all test groups but no other physical signs. Serum creatine phosphokinase (CPK) values were increased in mice in the two highest dose groups and minimal heart lesions were found in the highest dose group. Dogs given daily oral doses of 0, 1.25, 2.5, 5 or 7.5 mg/kg monensin for 1 yr survived with no evidence of toxicity in the two lowest dose groups.(ABSTRACT TRUNCATED AT 250 WORDS)