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Despite recent advances in surgical technique using laparoscopic and robotic approaches for the management of early organ-confined prostate cancer, most contemporary reports demonstrate significant rates of erectile dysfunction comparable to standard open approaches. Controversy remains related to many of the pre-and postoperative management strategies, including agents to enhance nerve recovery, erectogenic drugs, antioxidants, vasoactive injectables, vacuum erection devices and nerve grafting procedures. Additionally, the optimal timing of these interventions and their duration, dose, frequency and outcome thresholds remain ill-defined. In our paper, we provide a comprehensive literature review involving both the basic and clinical data surrounding rehabilitative approaches. 相似文献
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The dragon lizard <Emphasis Type="Italic">Pogona vitticeps</Emphasis> has ZZ/ZW micro-sex chromosomes 总被引:1,自引:0,他引:1
Tariq?EzazEmail author Alexander?E.?Quinn Ikuo?Miura Stephen?D.?Sarre Arthur?Georges Jennifer?A.?Marshall Graves 《Chromosome research》2005,13(8):763-776
The bearded dragon, Pogona vitticeps (Agamidae: Reptilia) is an agamid lizard endemic to Australia. Like crocodilians and many turtles, temperature-dependent
sex determination (TSD) is common in agamid lizards, although many species have genotypic sex determination (GSD). P. vitticeps is reported to have GSD, but no detectable sex chromosomes. Here we used molecular cytogenetic and differential banding techniques
to reveal sex chromosomes in this species. Comparative genomic hybridization (CGH), GTG- and C-banding identified a highly
heterochromatic microchromosome specific to females, demonstrating female heterogamety (ZZ/ZW) in this species. We isolated
the P. vitticeps W chromosome by microdissection, re-amplified the DNA and used it to paint the W. No unpaired bivalents were detected in
male synaptonemal complexes at meiotic pachytene, confirming male homogamety. We conclude that P. vitticeps has differentiated previously unidentifable W and Z micro-sex chromosomes, the first to be demonstrated in an agamid lizard.
Our finding implies that heterochromatinization of the heterogametic chromosome occurred during sex chromosome differentiation
in this species, as is the case in some lizards and many snakes, as well as in birds and mammals. Many GSD reptiles with cryptic
sex chromosomes may also prove to have micro-sex chromosomes. Reptile microchromosomes, long dismissed as non-functional minutiae
and often omitted from karyotypes, therefore deserve closer scrutiny with new and more sensitive techniques. 相似文献
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Ameyaw MM Tayeb M Thornton N Folayan G Tariq M Mobarek A Evans DA Ofori-Adjei D McLead HL 《Journal of human genetics》2002,47(4):172-175
HER-2, a protooncogene located on chromosome 17q21, encodes a transmembrane glycoprotein (p185) with tyrosine kinase activity.
Alterations of the HER-2 gene have been implicated in the carcinogenesis and prognosis of breast cancer and other solid tumors. It is also a cancer-therapeutic
target for antibody-based therapy against the HER-2 protein. A single-nucleotide polymorphism (SNP) at codon 655, resulting in a G-to-A transition (Ile655Val) in the transmembrane
domain-coding region of this gene has been associated with an increased risk of breast cancer, particularly among younger
women. To understand the importance of this finding throughout the world, we evaluated this polymorphism in Ghanaian, Kenyan,
Sudanese, Caucasian, African–American, Saudi, and Filipino subjects using a polymerase chain reaction-restriction fragment
length polymorphism assay. The frequency of the Val allele, which is associated with increased breast cancer risk, was highly
variable between populations (0%–24%). Continental African populations had a lower frequency of the Val allele than did Saudi,
Chinese, Filipino, Caucasian, and African–American subjects. The data suggest that this SNP has variable frequency in different
ethnic groups. The findings in this study correspond with the lower incidence and lower risk of breast cancer in African women
compared with Caucasian and African–American women.
Received: December 13, 2001 / Accepted: January 16, 2002 相似文献
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Haseeb Khan Ahmad Saleh Al Deeb Khalaf Al Moutaery Mohammad Tariq 《Experimental and toxicologic pathology》2003,55(2-3):181-186
A direct association between aging and drug-induced dyskinesia has been reported by several investigators. Iminiodipropionitrile (IDPN), a prototype nitrile compound produces a motor syndrome in rodents, which resembles neuroleptic drug induced dyskinesia. In this investigation attempt has been made to study the effect of age on IDPN induced vestibular hair cell degeneration and resulting dyskinetic syndrome. Male Wistar rats aged 3, 6 and 12 weeks received IDPN in the doses of 0, 200 and 400 mg/kg, intraperitoneally for 3 consecutive days. IDPN-induced dyskinesia was assessed using a behavioral testing battery on days 3, 4, 5, 6, 7, 14, 21 and 28. The rats were sacrificed on day 28; temporal bones were excised for vestibular histopathology and sera were collected for measuring the indices of oxidative stress (glutathione and conjugated dienes). IDPN in the dose of 200 mg/kg produced dyskinesia in 12 weeks old rats, but failed to do so in 3 and 6 weeks old rats. The high dose of IDPN (400 mg/kg) caused dyskinesia in all age groups, however, its onset and severity were age-dependent. Older rats showed an early onset and significantly high incidence of dyskinesia as compared to younger rats. The susceptibility of rats to IDPN-induced behavioral deficits was proportional to oxidative stress and degeneration of sensory hair cells in the crista ampullaris. 相似文献
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Ectodermal dysplasias (EDs) are developmental disorders affecting tissues of ectodermal origin including hair, nails, teeth and sweat glands. Ectodermal dysplasia of hair, nails and teeth is a rare type of congenital disorder characterized by sparse and thin hair, dystrophic finger-and toenails and missing and abnormal teeth. In an effort to understand the molecular basis of this form of ED a family of Pakistani origin with an autosomal recessive pattern of inheritance was ascertained from a remote region in Pakistan. The clinical features of the affected individuals included thin and fine hair on the scalp, dystrophic and flat nails, absent or sparse eyebrows and eyelashes, missing and abnormal teeth, and thin body hair. A human genome scan carried out using microsatellite markers mapped the disease locus in this family to chromosome 18q22.1–18q22.3. A maximum two-point LOD score of 2.73 (θ= 0.0) was obtained at marker D18S541. Multipoint linkage analysis resulted in a maximum LOD score of 3.42 obtained with several markers, including D18S1125, ATA82B02, D18S848, D18S488, D18S1091, and D18S485, which supported the linkage. The linkage interval is flanked by markers D18S857 and D18S815, which corresponds to a region of 17.32 cM according to Rutgers combined linkage and physical map (build 36). This region covers 8.63 Mb according to the sequence-based physical map. Three candidate genes, CDH7, CDH19 and ZNF407 , from the linkage interval were sequenced and found to be negative for functional sequence variants. This study is the first step towards the identification of a gene involved in hair, nails and teeth type ED. 相似文献
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Modelling and simulation methods can play an important role in guiding public health responses to infectious diseases and emerging health threats by projecting the plausible outcomes of decisions and interventions. The 2003 SARS epidemic marked a new chapter in disease modelling in Canada as it triggered a national discussion on the utility and uptake of modelling research in local and pandemic outbreaks. However, integration and application of model-based outcomes in public health requires knowledge translation and contextualization. We reviewed the history and performance of Pan-InfORM (Pandemic Influenza Outbreak Research Modelling), which created a national infrastructure in Canada with a mandate to develop innovative knowledge translation methodologies to inform policy makers through modelling frameworks that bridge the gaps between theory, policy, and practice. This review demonstrates the importance of a collaborative infrastructure as a “Community of Practice” to guide public health responses, especially in the context of emerging diseases with substantial uncertainty, such as the COVID-19 pandemic. Dedicated resources to modelling and knowledge translation activities can help create synergistic strategies at the global scale and optimize public health responses to protect at-risk populations and quell socioeconomic and health burden. 相似文献