Use of stem cells in the biological repair of articular cartilage

IMPORTANCE OF THE FIELD

Articular cartilage is avascular, aneural, and renowned for its poor capacity to repair after damage. For decades scientists and clinicians have deliberated over the potential to repair or regenerate articular cartilage and to date many techniques have been used in an attempt to create the best possible repair tissue.

AREAS COVERED IN THIS REVIEW

This review article summarises surgical interventions that have been developed since the late 1940's; covering conservative strategies, invasive techniques and touching upon latest advancements involving stem cells and tissue engineering.

WHAT WILL THE READER GAIN

The reader will gain a sound understanding into the history and background of strategies that have developed in attempts to reverse clinical symptoms of damaged or diseased articular cartilage. The article provides an insight into the plethora of potential repair mechanisms, and reviews future developments involving stem cells and biomaterials.

TAKE HOME MESSAGE

Although work is still in its infancy, the use of stem cells in the biological repair of articular cartilage provides a promising outlook onto future developments; advancing from strategies and techniques that are already in use.

Factors associated with positive tuberculin skin test results among HIV-infected persons in Orel Oblast, Russia

BACKGROUND

The treatment of persons living with human immunodeficiency virus/acquired immune-deficiency syndrome (PLWHAs) for latent tuberculosis infection (LTBI) reduces tuberculosis (TB) morbidity. Despite a high TB burden and an expanding human immunodeficiency virus epidemic, Russia had limited data on the utility of the tuberculin skin test (TST) for LTBI diagnosis in PLWHAs.

OBJECTIVE

To determine the prevalence and predictors of positive TSTs in PLWHAs in Orel Oblast.

METHODS

A total of 150 consenting PLWHAs being followed up at the AIDS Center were administered a TST and a questionnaire for risk factors for LTBI. A positive TST result was defined as >or=5 mm induration.

RESULTS

Of the 150 subjects, 67% were male and 74% were aged <30 years. Of the PLWHAs tested, 26% had a positive TST result, while among PLWHAs with CD4(+) >500 cells/ml, 36% were TST-positive. TST positivity varied inversely with CD4(+) cell count. Among PLWHAs with a history of injection drug use, the primary risk factor for HIV, 29 (31.9%) were positive.

CONCLUSIONS

A high proportion of tested PLWHAs had a positive TST and could benefit from preventive therapy (PT) to reduce the risk of TB. A TB control programme in Russia should therefore include TST screening among PLWHAs and PT, besides active TB case finding and treatment.

Second-trimester genetic sonogram for detection of fetal chromosomal abnormalities in a community-based antenatal testing unit

OBJECTIVE

To evaluate the efficacy of the second-trimester genetic sonogram for the detection of Down syndrome and other chromosomal abnormalities in a community-based antenatal testing unit.

METHODS

This was a retrospective study using data from two community hospital antenatal ultrasound units. Six hundred and sixty fetal ultrasound examinations in both at-risk (n = 581) and low-risk (n = 79) pregnancies were performed from 15 + 0 to 22 + 6 weeks' gestation and all cases were verified for outcome data. The sonographic detection of a major congenital anomaly or a sonographic marker (increased nuchal skinfold, short humerus, short femur, echogenic bowel, pyelectasis, echogenic intracardiac focus, absence or hypoplasia of fifth mid phalanx or choroid plexus cyst) was recorded. The entire group of 660 ultrasound examinations as well as subgroups with and without non-ultrasound risk factors for a fetal chromosomal abnormality were analyzed to determine the sensitivity, specificity, positive and negative predictive values and positive likelihood ratio for the detection of Down syndrome and other fetal chromosomal abnormalities.

RESULTS

There were 32 (4.85%) chromosomal abnormalities in our study population. Twelve (3.75%) of these were Down syndrome, of which eight (66.6%) had a positive ultrasound examination in the second trimester. Six of seven (85.7%) of the trisomy 18 fetuses, 2/2 of the trisomy 13 fetuses and 2/3 of the non-mosaic 45,X fetuses had positive sonograms. The overall detection rate for chromosomal abnormalities was 20/32 (sensitivity, 62.5%; specificity, 80.7%; negative predictive value, 97.7%; positive predictive value, 14.2%; positive likelihood ratio, 3.24). Major structural defects and sonographic markers, excluding hypoplastic fifth digit and choroid plexus cyst, occurred significantly more frequently in Down syndrome cases compared with normal ones.

CONCLUSIONS

In a community-based antenatal testing unit we have demonstrated a detection rate for fetal Down syndrome with the second-trimester genetic sonogram that is comparable to the range of sensitivities reported by larger centers involving primarily high-risk patients. However, only 12 of the 32 fetal chromosomal abnormalities that we encountered were Down syndrome.

Plastic surgical options for HIV-associated lipodystrophy

With the reported prevalence of HIV-associated lipodystrophy approaching 80%, this patient group presents an increasing challenge to plastic surgeons. Based on a literature search conducted using OVID Medline, this review shall describe the various treatment options employed by plastic surgeons to deal with the problems of fat distribution in patients suffering from HIV-lipodystrophy, and examine the evidence for each treatment.

Experience in the treatment of HIV-associated lipodystrophy

AIM

To evaluate the outcome of patients with HIV-associated lipodystrophy treated within the Edinburgh unit to date.

METHODS

Information was collected from the medical case notes on the clinical features, method of treatment, postoperative complications, and length of follow up for each patient. A questionnaire was devised to assess patient satisfaction and facial volume was evaluated using three-dimensional imaging.

RESULTS

Forty-six patients with HIV-associated lipodystrophy were treated over a 3-year period. Twenty-six patients received Coleman fat injections, 10 patients were treated with Newfill, eight patients were treated with Bio-alcamid, 21 patients received liposuction, and three patients had a minimal access cranial suspension facelift. Follow up ranged from 1 to 14 months. Patient and surgeon satisfaction was high with autologous fat injections although fat resorption occurred in nine patients. Aesthetic improvement with Newfill was moderate and required up to seven treatment sessions. The results of treatment with Bio-alcamid were good immediately postoperatively, although two patients required further corrective procedures. Two patients who had liposuction to the dorso-cervical fat pad reported recurrence at 5 and 9 months, respectively.

CONCLUSIONS

Based on our experience, a treatment algorithm has been devised to aid management decisions. We favour the use of autologous fat injections for facial lipoatrophy but have found fillers to be useful in patients with inadequate fat reserves.