When should patients begin ambulating following lower limb split skin graft surgery? A systematic review

Pretibial lacerations and lower limb wounds are referred to plastic surgery teams for split skin graft surgery. Traditionally, these patients have been immobilised on bedrest following surgery. More recently, patients have commenced ambulation earlier to avoid medical complications and facilitate discharge. The objective of this literature review was to determine when such patients should begin walking. A literature search was undertaken using the electronic databases AMED, Cinahl, Embase, Medline (via Ovid), PEDro and Pubmed. Clinical trials using human subjects, written in English, were included. Seventeen (of 1137) papers met the inclusion criteria and were reviewed. The literature suggested that patients should begin walking immediately or at the earliest possible opportunity after lower limb skin graft surgery. Although the literature advocated early ambulation, the evidence base presented with a number of recurrent methodological limitations, including small sample sizes, lack of a control sample, and limited follow-up. Accordingly, further research employing large, well-designed, randomised controlled trials is recommended. It will then be possible to understand with greater certainty when patients should begin walking after lower extremity split skin graft surgery.     

Genome scan for loci involved in nonsyndromic cleft lip with or without cleft palate in families from West Bengal, India

In order to identify genes or regions involved in nonsyndromic cleft lip with or without cleft palate (CL/P) in families from India, we analyzed 38 multiplex families (DNA from 272 individuals, 82 affected with CL/P, 190 unaffected) for 285 genome-wide markers (average spacing 12.6 cM), including markers in six candidate loci or regions on chromosomes 2, 4, 6, 14, 17, and 19 that have been implicated in other studies of CL/P. LOD scores (two-point and multipoint), and model-free association (TDT) and linkage (NPL) statistics, were calculated between each of the markers and a hypothetical CL/P susceptibility locus. The most statistically significant two-point linkage results were with markers on chromosome 7 (LOD = 1.89 with D7S435, 7p15, 47 cM), chromosome 5 (LOD = 1.76 with D5S407, 5q11, 65 cM), chromosome 15 (LOD = 1.55 with D15S652, 15q26, 90 cM), and chromosome 20 (LOD = 1.46 with STS155130, 20q13, 54 cM). The most significant multipoint linkage result was on chromosome 5q, again near D5S407 (HLOD = 1.40). Regions on chromosomes 1p, 1q, 7q, 12q, 16q, 18q, and Xp also had a LOD or HLOD > or = 1.0. Of seven candidate markers and regions with previous positive reports in the literature (TGFA, MSX1, D4S175, F13A1, TGFB3, D17S250, and APOC2), none had a significant linkage result, but one (the APOC2 region) had a significant association result and three others (TGFA, MSX1, F13A1) had suggestive results. The results are consistent with the involvement of multiple loci in CL/P expression in this West Bengal population, which concurs with results found in other CL/P study populations.     

MR properties of excised neural tissue following experimentally induced demyelination

Changes in the magnetic resonance (MR) parameters of demyelinated neural tissue were measured in vitro using an experimental animal model. A tellurium (Te) diet was applied to weanling rats to induce the demyelination process in the sciatic nerve. The quantitative MR parameters, such as T(1), T(2) relaxation time constants and magnetization transfer (MT) were measured each day after applying the Te diet (up to 7 days) and were found to be substantially different from those of normal nerves. An increase in the average T(1) and T(2) was observed along with a decrease in the MT ratio (MTR) and the quantitative MT parameter M(0B), which describes the semisolid pool of protons. Most of the MR parameters correlated very well with the myelin fraction of neural tissue evaluated by quantitative histopathology. The T(2) relaxation spectrum provided the most efficient quantitative assessment of changes in neural tissue microstructure and its analysis resulted in a powerful tool to distinguish the processes of demyelination and inflammation. In comparison, the MT measurements were less successful.     

Effect of Down syndrome on the dimensions of dental crowns and tissues

Abnormal growth in Down syndrome (DS) is reflected by variable reduction in size and simplification in form of many physical traits. This study aimed to compare the thickness of enamel and dentine in deciduous and permanent mandibular incisor teeth between DS and non‐DS individuals and to clarify how these tissues contribute to altered tooth size in DS. Sample groups comprised 61 mandibular incisors (29 permanent and 32 deciduous) from DS individuals and 55 mandibular incisors (29 permanent and 26 deciduous) from non‐DS individuals. Maximum mesiodistal and labiolingual crown dimensions were measured initially, then the crowns were sectioned midsagittally and photographed using a stereomicroscope. Linear measurements of enamel and dentine thickness were obtained on the labial and lingual surfaces of the crowns, together with enamel and dentine–pulp areas and lengths of the dentino‐enamel junction. Reduced permanent crown size in DS was associated with a reduction in both enamel and dentine thickness. After adjustments were made for tooth size, DS permanent incisors had significantly thinner enamel than non‐DS permanent teeth. The DS permanent teeth also exhibited significant differences in shape and greater variability in dimensions than the non‐DS permanent teeth. Crown dimensions of deciduous incisors were similar in size or larger in DS compared with non‐DS deciduous teeth. Enamel and dentine thicknesses of the deciduous teeth were similar in DS and non‐DS individuals. The findings indicate that growth retardation in DS reduces both enamel and dentine deposition in the permanent incisors but not in the earlier‐forming deciduous predecessors. The results are also consistent with the concept of amplified developmental instability for dental traits in DS. Am. J. Hum. Biol. 13:690–698, 2001. © 2001 Wiley‐Liss, Inc.     

Disorientation following stroke: Frequency,course, and clinical correlates

To investigate the frequency, course, and clinical correlates of disorientation following stroke, we administered the Mini-Mental State Examination orientation subtest to 177 alert patients 7–10 days and 3 months after stroke and 240 stroke-free nondemented subjects. Disorientation was defined as a score 8/10. Seventy-two (40.7%) of the patients were disoriented 7–10 days after stroke and 39 patients (22.0% of the sample) remained disoriented 3 months later. A logistic regression analysis determined that persistent disorientation was significantly related to stroke status [odds ratio (OR)=5.8], after adjusting for memory and attentional deficits and demographic variables. Among stroke patients, disorientation was associated with severe hemispheral stroke syndromes (OR=7.7), but not infarct location or vascular risk factor history, after adjusting for memory and attentional deficits and demographic variables. Sensitivity and specificity analyses determined that disorientation was an inaccurate marker for dementia or deficits in memory or attention, while intact orientation was associated with a low probability of dementia or memory dysfunction in most patients but not preserved attention. We conclude that disorientation is common and persistent following stroke and associated with severe hemispheral stroke syndromes but not infarct location. While disorientation is a poor marker for dementia or deficits in memory or attention, intact orientation should suggest that cognitive functions are likely to be preserved.Presented in part at the 118th Annual Meeting of the American Neurological Association, Boston, Massachusetts, October 1993     

Altered neural control of micturition in the aged F344 rat

The purpose of this study was to determine whether micturition reflexes are altered in aged rats. Voiding frequencies and awake cystometrograms (CMGs) were measured in young (3–5 months old) and aged (24 months) F344 male rats. Bladder contractions induced by subcutaneous apomorphine and intravesical capsaicin stimulation were measured using awake CMGs. Urodynamic parameters were compared. Aged rats voided less frequently (4.1 vs 6.9 times/18 h, P=0.006), with a higher volume per void (1.1 vs 0.7 ml, P=0.02) and had a higher micturitional threshold pressure (8.7 vs 4.6 mmHg, P=0.0001) than the young rats. Apomorphine induced a higher frequency of bladder contractions in aged animals compared to young animals (5.5 vs 3.1 contractions/min, P=0.03). Intravesical capsaicin caused a lower pressure bladder response in the aged rats (38.5 vs 70.6 mmHg, P=0.01) compared to the young rats. Bladder afferents and central micturition pathways may be altered in aged rats. Impaired bladder contractility in the elderly may be exacerbated by reduced sensory input, whereas the propensity for detrusor instability could result from altered central processing. This study demonstrated the utility of the F344 animal model to study micturitional changes resulting from aging. Received: 14 April 2000 / Accepted: 4 July 2000