Hip Labral Reconstruction: Techniques and Outcomes.

PURPOSE OF REVIEW: With increased understanding of the biomechanical function of the acetabular labrum, more attention has been directed towards surgical techniques that preserve or restore normal joint anatomy. While labral repair has been shown to produce superior outcomes to labral debridement, repair is not always possible in the setting of severe labral intrasubstance tearing or deficiency. These patients were previously left without suitable arthroscopic treatment options. RECENT FINDINGS: Labral reconstruction is an emerging procedure that has been shown to offer promising outcomes for traditionally difficult-to-treat hip pathology. Short- and mid-term follow-up studies have consistently demonstrated significant improvement in patient-reported outcomes, function, and patient satisfaction postoperatively, often despite less favorable preoperative characteristics. Labral reconstruction is a viable arthroscopic treatment option that has been shown to reliably produce clinically meaningful results in patients with severe labral pathology that is not amenable to repair/refixation or augmentation.

Topical retinoic acid (tretinoin) for melasma in black patients. A vehicle-controlled clinical trial.

BACKGROUND AND DESIGN: Melasma is an acquired, masklike, facial hyperpigmentation. The pathogenesis and treatment of melasma in black (African-American) patients is poorly understood. We investigated the efficacy of topical 0.1% all-trans-retinoic acid (tretinoin) in the treatment of melasma in black patients. Twenty-eight of 30 black patients with melasma completed a 10-month, randomized, vehicle-controlled clinical trial in which they applied either 0.1% tretinoin or vehicle cream daily to the entire face. They were evaluated clinically (using our Melasma Area and Severity Index), colorimetrically, and histologically. RESULTS: After 40 weeks, there was a 32% improvement in the Melasma Area and Severity Index score in the tretinoin treatment group compared with a 10% improvement in the vehicle group. Colorimetric measurements showed lightening of melasma after 40 weeks of tretinoin treatment vs vehicle. Lightening of melasma, as determined clinically, correlated well with colorimetric measurements. Histologic examination of involved skin revealed a significant decrease in epidermal pigmentation in the tretinoin group compared with the vehicle group. Side effects were limited to a mild "retinoid dermatitis" occurring in 67% of tretinoin-treated patients. Among the patients in this study in comparison with comparably recruited white patients, melasma was reported to have begun at a later age and was more likely to be in a malar distribution. CONCLUSIONS: This controlled study demonstrates that topical 0.1% tretinoin lightens melasma in black patients, with only mild side effects.

Topical tretinoin (retinoic acid) therapy for hyperpigmented lesions caused by inflammation of the skin in black patients.

BACKGROUND AND METHODS: Irregular disfiguring skin hyperpigmentation due to inflammation may develop in black persons. We investigated the treatment of this hyperpigmentation with topical tretinoin (0.1 percent retinoic acid cream). Fifty-four subjects completed a 40-week randomized, double-blind, vehicle-controlled study. Twenty-four subjects applied tretinoin daily to the face, arms, or both areas, and 30 subjects applied vehicle cream. At base line and after 40 weeks of treatment, each subject's post-inflammatory hyperpigmented lesions and normal skin were assessed by clinical and colorimetric evaluations and by analysis of biopsy specimens. RESULTS: The facial post-inflammatory hyperpigmented lesions of the tretinoin-treated subjects were significantly lighter after the 40 weeks of therapy than those of the vehicle-treated subjects (P < 0.001); overall improvement was first noted after four weeks of tretinoin treatment. At the end of treatment, colorimetry demonstrated a 40 percent lightening of the lesions toward normal skin color in the tretinoin-treated lesions, as compared with an 18 percent lightening in vehicle-treated lesions (P = 0.05). The epidermal melanin content in the lesions decreased by 23 percent with tretinoin and by 3 percent with vehicle (P = 0.24). Normal skin was minimally lightened by tretinoin as compared with vehicle, according to both clinical evaluation (0.1 vs. -0.1 unit change on an 8-point scale; P = 0.055) and colorimetry (P < 0.001). Retinoid dermatitis developed in 12 of the 24 tretinoin-treated subjects who completed the study (50 percent) and in 1 tretinoin-treated subject who withdrew from the study, but diminished as the study progressed. CONCLUSIONS: Topical application of tretinoin significantly lightens post-inflammatory hyperpigmentation and, to a clinically minimal but statistically significant degree, lightens normal skin in black persons.

Guanylyl cyclase is a heat-stable enterotoxin receptor.

Plasma membrane forms of guanylyl cyclase have been shown to function as natriuretic peptide receptors. We describe a new clone (GC-C) encoding a guanylyl cyclase receptor for heat-stable enterotoxin. GC-C encodes a protein containing an extracellular amino acid sequence divergent from that of previously cloned guanylyl cyclases; however, the protein retains the intracellular protein kinase-like and cyclase catalytic domains. Expression of GC-C in COS-7 cells results in high guanylyl cyclase activity. In addition, heat-stable enterotoxin from E. coli, but not natriuretic peptides, causes marked elevations of cyclic GMP and is specifically bound by cells transfected with GC-C. The enterotoxin fails to elevate cyclic GMP in nontransfected cells or in cells transfected with the natriuretic peptide/guanylyl cyclase receptors. These results show that a heat-stable enterotoxin receptor responsible for acute diarrhea is a plasma membrane form of guanylyl cyclase.

Genetic variation in Cumbrians.

Regional variation in the genetic constitution of the Cumbrian population is demonstrated in a survey of blood groups, red cell enzymes, and secretor status in a large sample of schoolchildren. In particular, the south and centre appear to be distinct from the remainder of Cumbria, but in different directions. The features of the central Lake District, tending towards gene frequencies observed in Norway, suggest that it may be a region in which the presence of a relict population is still detectable.