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Intra-lesional injections of collagenase are ineffective in the treatment of keloid and hypertrophic scars. 总被引:2,自引:0,他引:2
Norbert Kang Branavan Sivakumar Roy Sanders Charles Nduka David Gault 《Journal of plastic, reconstructive & aesthetic surgery》2006,59(7):693-699
The treatment of keloid and hypertrophic scars remains difficult. Enzymatic digestion of keloid scars has been previously proposed as an effective treatment strategy for reducing the volume of keloid scars. To test this, we administered intra-lesional injections of pure collagenase (between 600 and 4500 units for each scar) into the keloid and hypertrophic scars of seven human volunteers (five keloid and two hypertrophic scars). Five patients (three keloid and two hypertrophic) received more than one injection of collagenase. The treatment resulted in a temporary reduction in scar volume for three of the patients with keloid scars. However, scar volumes for these three patients returned to the same (or greater) levels after 6 months of follow-up. Treatment with collagenase produced no change in scar volume for the two patients with hypertrophic scar. Side effects were numerous and severe including; pain, swelling, blistering, ulceration and ecchymosis at the site of injection. One patient required admission to hospital for 48 h after the first injection. Maximum length of follow-up was 6 months. None of the seven patients completed the study and returned for final follow-up at 2 years. This pilot study suggests that treatment of keloid and hypertrophic scars with intra-lesional injections of collagenase is ineffective. 相似文献
4.
Premature fusion of cranial sutures in craniosynostosis has been thought to lead to craniostenosis, which in turn may lead to increased intracranial pressures. In 41 consecutive patients with craniosynostosis, intracranial pressure and intracranial volume were measured. Of the 41 patients, 38 (92.6%) had raised intracranial pressure but only 4 (9.7%) had a decreased skull volume. In the present study, there is no correlation between intracranial volume and intracranial pressure. This study confirms that the measurement of intracranial volume, a non invasive procedure, cannot be used to assess intracranial pressure and to avoid an invasive procedure. 相似文献
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We showed previously that nonimmune human milk (NHM) kills Giardia lamblia trophozoites in vitro and presented evidence that killing requires the bile salt-stimulated lipase of milk. Since this enzyme is activated by bile salts, killing should be dependent on the presence of bile salts. We now show that killing by fresh NHM or NHM stored at -70 degrees C is totally dependent on sodium cholate (a bile salt). With less than 0.4 mM cholate, no parasites were killed, whereas with 1 mM cholate, greater than 99.7% were killed by 5% NHM in 30 min. Moreover, killing activity was completely heat labile. The G. lamblia-killing activity of human milk was greatly altered by storage at -10 or -20 degrees C. In less than 23 days, the 50% lethal dose decreased, cholate dependence was lost, and killing activity became heat stable. In contrast, the activity of milk stored at -70 degrees C remained unchanged. Milk lipase activity, like killing activity, became cholate independent during storage at -10 or -20 degrees C. On the basis of these results, we hypothesize that killing of G. lamblia by fresh NHM or NHM stored at -70 degrees C depends on bile salt-stimulated lipase, which must be activated by bile salts. In contrast, NHM stored at -20 degrees C accumulated free fatty acids which kill G. lamblia. In support of this thesis, milk stored at -10 degrees C had a concentration of 18.7 mM free fatty acids compared with only 1.1 mM in an identical sample stored at -70 degrees C. 相似文献
7.
乳腺管状小叶癌(Tubulolobular carcinoma,TLC)最初是被作为小叶癌的管状变型。作者总结了27例TLC的组织学、免疫表型和临床特征,并与纯小管癌和经典型小叶癌进行了比较。此组患者年龄43-79岁(中位年龄60岁)。1例双侧乳腺受累,5例病变为多灶性。肿瘤直径0.5-2.5cm,色灰褐,质硬。组织学观察:TLC的肿瘤细胞形成管状和条索状两种结构模式并相互混杂,且两者比例相当(统称为管状小叶模式)。 相似文献
8.
Germline mutations of the CDKN2 gene in UK melanoma families 总被引:4,自引:1,他引:4
Harland M; Meloni R; Gruis N; Pinney E; Brookes S; Spurr NK; Frischauf AM; Bataille V; Peters G; Cuzick J; Selby P; Bishop DT; Bishop JN 《Human molecular genetics》1997,6(12):2061-2067
Germline mutations in CDKN2 on chromosome 9p21, which codes for the cyclin
D kinase inhibitor p16, and more rarely, mutations in the gene coding for
CDK4, the protein to which p16 binds, underlie susceptibility in some
melanoma families. We have sequenced all exons of CDKN2 and analysed the
CDK4 gene for mutations in 27 UK families showing evidence of
predisposition to melanoma. Five different germline mutations in CDKN2 were
found in six families. Three of the mutations (Met53Ile, Arg24Pro and
23ins24) have been reported previously. We have identified two novel CDKN2
mutations (88delG and Ala118Thr) which are likely to be associated with the
development of melanoma, because of their co-segregation with the disease
and their likely functional effect on the CDKN2 protein. In binding assays
the protein expressed from the previously described mutation, Met53Ile, did
not bind to CDK4/CDK6, confirming its role as a causal mutation in the
development of melanoma. Ala118Thr appeared to be functional in this assay.
Arg24Pro appeared to bind to CDK6, but not to CDK4. No mutations were
detected in exon 2 of CDK4, suggesting that causal mutations in this gene
are uncommon. The penetrance of these mutant CDKN2 genes is not yet
established, nor is the risk of non-melanoma cancer to gene carriers.
相似文献
9.
Three triploid infants, two male (69,XXY) and one female (69,XXX) all of which survived beyond 35 weeks' gestation are described. One was stillborn due to a difficult delivery, the other two survived for a few hours only. Two were of relatively low birth weight, the other was normal. There was no evidence of mosaicism in the tissue examined.
In keeping with previously reported triploid infants they showed a variety of abnormalities. From a total of 13 cases now reported the more frequent associated anomalies are low set ears, coloboma of the iris, syndactyly of the hands, a single palmar crease, abnormal male genitalia in XXY individuals, polycystic kidney, and congenital heart defect. The most common anomaly, however, is hydatidiform degeneration of a large placenta.
相似文献10.
Drazinic CM Ercan-Sencicek AG Gault LM Hisama FM Qumsiyeh MB Nowak NJ Cubells JF State MW 《American journal of medical genetics. Part A》2005,134(3):282-289
Array-based copy number analysis has recently emerged as a rapid means of mapping complex and/or subtle chromosomal abnormalities. We have compared two such techniques, using bacterial artificial chromosome (BAC) and single nucleotide polymorphism (SNP) arrays in the evaluation of a 45-year-old woman with dysmorphic features, mental retardation, psychosis, and an unbalanced derivative chromosome 18, (46,XX, der(18)t(18;?)(p12;?)). Both array-based methods demonstrated that the additional material on chromosome 18 was of 5p origin. The 5p duplication mapped telomeric to 25.320 Mb (BAC array) and 25.607 Mb (SNP array), corresponding to the band 5p14.1. Both BAC and SNP arrays also showed a deletion involving chromosome 18p extending telomeric from 8.437 Mb (BAC array) and 8.352 Mb (SNP array), corresponding to the band 18p11.23. Molecular cytogenetic mapping using fluorescence in situ hybridization (FISH) supported the array findings and further refined the breakpoint regions, confirming that the BAC and SNP chips were both useful in this regard. Both case reports and linkage analyses have implicated these chromosomal intervals in psychosis. The array-based experiments were completed over the course of several days. While these methods do not eliminate the requirement for traditional fine-mapping, they provide an efficient approach to identifying the origin and extent of deleted and duplicated material in chromosomal rearrangements. 相似文献