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H Shen

Publications and source records attributed to H Shen.

At least 37 records · Page 2Linked to original sources
PubMed2005

Lateral supraorbital approach as an alternative to the classical pterional approach.

OBJECTIVE: The standard pterional approach has been used to approach aneurysms of the anterior circulation and the basilar tip, suprasellar tumors, cavernous lesions. The senior author (JH) established a lateral supraorbital approach as an alternative to the pterional approach after continuous trial and error. We describe the techniques of this approach based on clinical experiences. METHODS: The lateral supraorbital approach is more subfrontal and anterior than the pterional approach. This approach has been regularly used by the senior author (JH) in the last decade in more than 2000 operations for mostly aneurysms of anterior circulation, but also for tumors of the anterior fossa and parasellar area as well as the sphenoid wing area. RESULTS: This approach can be used to operate on most cases, in which the classical pterional approach would be used. There are almost no craniotomy-related complications with this approach. This approach is not suitable in certain lesions which need to be exposed from a more temporal perspective. CONCLUSION: This approach is simpler, faster, safer and less invasive than the classical pterional approach.

Humans↗
PubMed2005

Subtemporal approach to basilar bifurcation aneurysms: advanced technique and clinical experience.

OBJECTIVE: The surgical treatment of basilar bifurcation aneurysms is challenging, and many of these aneurysms are currently treated by endovascular means. However, the complete closure of the aneurysm by surgical clipping still remains the best and most permanent cure for the aneurysm. The "gold standard", subtemporal approach was established and introduced by Drake and it has been adapted by the senior author Hernesniemi. We describe our present modified technique of this approach based on clinical experience. METHODS: The subtemporal approach to basilar bifurcation aneurysms has been regularly used by the senior author Hernesniemi in recent 15 years in over 200 operations in Kuopio and Helsinki, Finland. RESULTS: This approach is suitable in most basilar bifurcation aneurysms except for those high above the posterior clinoid process. To avoid temporal lobe damage, cerebrospinal fluid drainage is necessary. Benefits of subtemporal approach are short operative and retraction times, and no need for skull base resection. CONCLUSION: The subtemporal approach is simple and safe in experienced hands, and should be considered the standard method to approach most basilar bifurcation aneurysms.

Basilar Artery↗
PubMed2005

A common polymorphism in the 3'UTR of cyclooxygenase 2/prostaglandin synthase 2 gene and risk of lung cancer in a Chinese population.

Cyclooxygenases (COXs) are key enzymes that convert arachidonic acid to prostaglandins. Overexpression of COX-2, one of the COX isozymes, has been shown to be an early event in lung carcinogenesis and may play an important role in lung cancer development. A common single nucleotide polymorphism, T8473C, located within a potential functional region in the 3'UTR of COX-2 gene was identified and we hypothesized that this COX-2 variant is associated with lung cancer risk. To test this hypothesis, we genotyped this variant in a case-control study of 322 histologically-confirmed lung cancer patients and 323 age and sex frequency-matched cancer-free controls in a Chinese population. The results showed that the frequencies of variant genotypes 8473CT/CC were significantly less common in the cases (27.3%) than in the controls (35.3%) (P=0.034), suggesting that the 8473C allele was protective against lung cancer. Multivariate logistic regression analyses revealed that the COX-2 variant genotypes (8473CT/CC) were associated with a significantly decreased risk of lung cancer compared with the 8473TT wild-type homozygotes (OR=0.64, 95% CI=0.45-0.92). When we defined the reference group as non-smokers having the 8473CT/CC variant genotypes, the smokers with the 8473TT wild-type genotype had the greatest risk (adjusted OR=5.28, 95% CI=3.10-9.00). These findings indicate that the COX-2 T8473C polymorphism may contribute to lung cancer susceptibility in the Chinese population. Further larger molecular epidemiological studies are warranted to confirm these findings.

3' Untranslated Regions↗
PubMed2005

Vitamin D receptor gene polymorphisms are linked to and associated with adult height.

BACKGROUND: The vitamin D receptor (VDR) gene is important to human stature, as it mediates metabolic pathways, calcium homeostasis, and phosphate homeostasis, which influence growth. METHODS: We examined the relationship between VDR and adult height in 1873 white subjects from 406 nuclear families. Four SNPs, namely -4817A/G at intron 1, FokI C/T at exon 2 start codon, BsmI A/G at intron 8, and TaqI T/C at exon 9 in VDR were tested for linkage and association with adult height variation by the program QTDT (quantitative transmission disequilibrium test). The bT haplotype of the BsmI and TaqI loci was further tested for its association with height in unrelated samples randomly chosen from the 406 nuclear families by traditional population association methods. RESULTS: All four tested SNPs were linked to adult height. Within family associations with height were detected at BsmI and TaqI loci (p = 0.048 and 0.039, respectively). Analyses based on BsmI/TaqI haplotypes also revealed evidence for linkage (p = 0.05) and association (p = 0.001) with height. The bT haplotype was significantly associated with higher adult height (p = 0.033, within family association test). Such an association might be female specific and influenced by menstrual status. CONCLUSIONS: Our results strongly suggest that VDR may be linked to and associated with adult height variation in white populations.

Adult↗
PubMed2005

A survey of haplotype variants at several disease candidate genes: the importance of rare variants for complex diseases.

BACKGROUND: The haplotype based association method offers a powerful approach to complex disease gene mapping. In this method, a few common haplotypes that account for the vast majority of chromosomes in the populations are usually examined for association with disease phenotypes. This brings us to a critical question of whether rare haplotypes play an important role in influencing disease susceptibility and thus should not be ignored in the design and execution of association studies. METHODS: To address this question we surveyed, in a large sample of 1873 white subjects, six candidate genes for osteoporosis (a common late onset bone disorder), which had 29 SNPs, an average marker density of 13 kb, and covered a total of 377 kb of the DNA sequence. RESULTS: Our empirical data demonstrated that two rare haplotypes of the parathyroid hormone (PTH)/PTH related peptide receptor type 1 and vitamin D receptor genes (PTHR1 and VDR) with frequencies of 1.1% and 2.9%, respectively, had significant effects on osteoporosis phenotypes (p = 4.2 x 10(-6) and p = 1.6 x 10(-4), respectively). Large phenotypic differences (4.0 approximately 5.0%) were observed between carriers of these rare haplotypes and non-carriers. Carriers of the two rare haplotypes showed quantitatively continuous variation in the population and were derived from a wide spectrum rather than from one extreme tail of the population phenotype distribution. CONCLUSIONS: These findings indicate that rare haplotypes/variants are important for disease susceptibility and cannot be ignored in genetics studies of complex diseases. The study has profound implications for association studies and applications of the HapMap project.

Apolipoproteins E↗
PubMed2004

Fragile X premutation alleles in SCA, ET, and parkinsonism in an Asian cohort.

Among 367 subjects, the authors analyzed 167 patients with essential tremor, sporadic progressive cerebellar ataxia, multiple-system atrophy, and atypical parkinsonism and 200 healthy control subjects for FMR1 premutation alleles. None of the subjects carried alleles within the premutation range. These findings suggest that in the absence of other supportive clinical or imaging features, the cost-effectiveness of routine fragile X tremor/ataxia syndrome screening in this Asian cohort with movement disorders was low.

Adult↗
PubMed2004

A second-stage genome scan for QTLs influencing BMD variation.

Low bone mineral density (BMD) is a major risk factor for osteoporotic fracture. To identify genomic regions harboring quantitative trait loci (QTLs) contributing to BMD variation, we performed a two-stage genome screen. The first stage involved genotyping of a sample of 53 pedigrees with 630 individuals using 400 microsatellite markers spaced at approximately 10-cM intervals throughout the genome. Ten genomic regions with multi- and/or two-point LOD scores greater than 1.5 were observed. In the present second-stage study, 60 microsatellite markers, with a mean spacing of about 5 cM, were genotyped in these regions in an expanded sample of 79 pedigrees that contained 1816 subjects. Each pedigree was ascertained through a proband with extreme BMD at the hip or spine. BMD at the spine (L1-4), hip (the femoral neck, trochanter, and intertrochanteric region), and wrist (the ultradistal region) was measured by dual-energy X-ray absorptiometry (DXA) and was adjusted for age, sex, height, and weight. Two-point and multipoint linkage analyses were performed for each BMD site using statistical genetic methods that are implemented in the computer package SOLAR. Several regions (7q11, 10q26, 12q13, and 12q24) achieved LOD scores in excess of 1 in the second-stage followup study. The current results replicate some of our previous linkage findings and also highlight some of the difficulties facing microsatellite linkage mapping for complex human diseases.

Absorptiometry, Photon↗
PubMed2004

Alpha-synuclein haplotypes implicated in risk of Parkinson's disease.

The authors examined four- and six-loci haplotype constructs (from five single nucleotide polymorphisms and three microsatellite regions) of the alpha-synuclein gene in patients with Parkinson's disease (PD) and controls in an ethnic Chinese population. Logistic regression analysis demonstrated an association of NACP-Rep1 (p = 0.002) and L478 (p < 0.0001) with risk of PD after correction for the effects of age, sex, and the other polymorphic loci. Specific four-loci and six-loci haplotypes were significantly associated with an increased or decreased risk of PD.

Adult↗