Association of CXCL1 promoter polymorphism with ischaemic stroke in Korean population

This is a pilot study analysing association of chemokine gene polymorphisms (CXCL1, rs3117604; CXCL2, rs3806792; CCL2, rs2857656 and rs3760396; CCL5, rs2107538) in Korean patients with ischemic stroke (IS) (n = 120) and age-matched controls (n = 267). The CXCL1 gene and particularly T allele of rs3117604 was associated with IS.

Effects of alpha(1)-adrenoceptor (alpha(1)-AR) antagonists on cell proliferation and apoptosis in the prostate: therapeutic implications in prostatic disease

BACKGROUND

Benign prostate hyperplasia (BPH) and prostate cancer established that disruption of the molecular mechanisms that regulate apoptosis and cell proliferation among the stromal and epithelial cell populations, may underlie the neoplastic development that characterizes the aging gland. This work examined the effects of selected alpha(1)-adrenoceptor (alpha(1)-AR) antagonists (blockers) on cellular dynamics to determine whether induction of apoptosis or inhibition of proliferation could contribute to the overall clinical profile.

METHODS

Our efforts were focused on investigating whether alpha(1)-AR antagonists of two different chemical classes affect prostate pathophysiology via mechanisms other than smooth muscle contraction. In in vitro experiments, the two clinically used quinazoline alpha(1)-adrenoceptor antagonists terazosin and doxazosin and the chemically-distinct sulphonamide, tamsulosin, were examined for effects on prostatic tumor growth, by inhibiting cell proliferation and'or inducing apoptosis.

RESULTS

Our findings suggest that alpha(1)-AR antagonists, terazosin and doxazosin, suppress prostatic growth by inducing apoptosis in a dose-dependent manner and without affecting cell proliferation. Tamsulosin exerted no effect on prostate cancer cell growth. The apoptotic effect of terazosin and doxazosin appears to be independent of the alpha(1)-adrenoceptor block.

CONCLUSIONS

Taken together, our findings demonstrate the ability of the quinazoline alpha-blockers, terazosin and doxazosin, but not the sulphonamide, tamsulosin, to suppress prostate growth by inducing apoptosis among the epithelial cells in the benign and malignant prostate. These studies underwrite the durability of the response seen in long-term studies with terazosin, and suggest the potential of this drug in the treatment of prostate carcinoma.

Effects of alpha(1)-adrenoceptor (alpha(1)-AR) antagonists on cell proliferation and apoptosis in the prostate: therapeutic implications in prostatic disease

BACKGROUND

Benign prostate hyperplasia (BPH) and prostate cancer established that disruption of the molecular mechanisms that regulate apoptosis and cell proliferation among the stromal and epithelial cell populations, may underlie the neoplastic development that characterizes the aging gland. This work examined the effects of selected alpha(1)-adrenoceptor (alpha(1)-AR) antagonists (blockers) on cellular dynamics to determine whether induction of apoptosis or inhibition of proliferation could contribute to the overall clinical profile.

METHODS

Our efforts were focused on investigating whether alpha(1)-AR antagonists of two different chemical classes affect prostate pathophysiology via mechanisms other than smooth muscle contraction. In in vitro experiments, the two clinically used quinazoline alpha(1)-adrenoceptor antagonists terazosin and doxazosin and the chemically-distinct sulphonamide, tamsulosin, were examined for effects on prostatic tumor growth, by inhibiting cell proliferation and'or inducing apoptosis.

RESULTS

Our findings suggest that alpha(1)-AR antagonists, terazosin and doxazosin, suppress prostatic growth by inducing apoptosis in a dose-dependent manner and without affecting cell proliferation. Tamsulosin exerted no effect on prostate cancer cell growth. The apoptotic effect of terazosin and doxazosin appears to be independent of the alpha(1)-adrenoceptor block.

CONCLUSIONS

Taken together, our findings demonstrate the ability of the quinazoline alpha-blockers, terazosin and doxazosin, but not the sulphonamide, tamsulosin, to suppress prostate growth by inducing apoptosis among the epithelial cells in the benign and malignant prostate. These studies underwrite the durability of the response seen in long-term studies with terazosin, and suggest the potential of this drug in the treatment of prostate carcinoma.

High copy number suppression of the meiotic arrest caused by a dmc1 mutation: REC114 imposes an early recombination block and RAD54 promotes a DMC1-independent DSB repair pathway

BACKGROUND

DMC1, the meiosis-specific eukaryotic homologue of bacterial recA, is required for completion of meiotic recombination and cell cycle progression past prophase. In a dmc1 mutant, double strand break recombination intermediates accumulate and cells arrest in prophase. We isolated genes which, when present at high copy numbers, suppress the meiotic arrest phenotype conferred by dmc1 mutations.

RESULTS

Among the genes isolated were two which suppress arrest by altering the recombination process. REC114 suppresses formation of double strand break (DSB) recombination intermediates. The low viability of spores produced by dmc1 mutants carrying high copy numbers of REC114 is rescued when reductional segregation is bypassed by mutation of spo13. High copy numbers of RAD54 suppress dmc1 arrest, promote DSB repair, and allow formation of viable spores following reductional segregation. Analysis of the combined effects of a null mutation in RED1, a gene required for meiotic chromosome structure, with null mutations in RAD54 and DMC1 shows that RAD54, while not normally important for repair of DSBs during meiosis, is required for efficient repair of breaks by the intersister recombination pathway that operates in red1 dmc1 double mutants.

CONCLUSIONS

Over-expression of REC114 suppresses meiotic arrest by preventing formation of DSBs. High copy numbers of RAD54 activate a DMC1-independent mechanism that promotes repair of DSBs by homology-mediated recombination. The ability of RAD54 to promote DMC1-independent recombination is proposed to involve suppression of a constraint that normally promotes recombination between homologous chromatids rather than sisters.

Effects of cocaine-induced seizures during pregnancy in the rabbit

The effects of chronic administration of cocaine to pregnant rabbits on maternal seizures and on pregnancy outcome were studied. Cocaine (2, 3 or 4 mg/kg/injection) or saline was administered, I.V., twice daily, from gestation Day 8 (G8) to G29. There were no significant differences in maternal weight gain or pregnancy outcome between saline control animals and animals given a cocaine dose of 2, 3 or 4 mg/kg/injection. Generalized tonic-clonic seizures (GTCSs) were occasionally elicited by the highest dose (4 mg/kg). There were significant individual differences in vulnerability to cocaine-elicited GTCSs in animals given 4 mg/kg/injection. Of this group, 18% were classified as having high vulnerability to seizures, and they experienced a range from 3 to 27 GTCSs. Postnatal mortality of their offspring was significantly increased. The incidence and temporal patterns of GTCSs elicited by chronic, I.V. cocaine in rabbits, at the doses used, are similar to those reported in human cocaine use. These GTCSs may involve different mechanisms from seizures elicited in other animal studies, in which high doses of cocaine are administered I.P. or S.C. Nevertheless, in our animal model, the GTCSs elicited by prenatal cocaine exposure had no detectable effects on pregnancy outcome (except in the highly vulnerable subgroup).

Reconstruction with tenodesis in an adult flatfoot model. A biomechanical evaluation of four methods

Six fresh-frozen adult cadaveric specimens were mounted in an Instron materials testing machine with use of a cemented intramedullary rod. Angular relationships between the first metatarsal and the talus were recorded with a sonic digitizer. A flatfoot deformity was created by dividing the talonavicular joint capsule (superiorly, medially, and inferiorly), the spring ligament, the anteromedial aspect of the subtalar joint capsule, and the plantar fascia. Angular displacement in the sagittal and transverse planes was recorded at no load and at 100, 350, and 700-newton plantar loads. Each specimen was subjected to four different reconstructions with tenodesis, and the angular relationship between the first metatarsal and the talus was measured at the four levels of load. A reconstruction with use of the peroneus longus tendon was performed by preserving its insertion into the first metatarsal, rerouting the tendon and passing it from medial to lateral through a calcaneal bone tunnel, and anchoring it to the lateral aspect of the calcaneus. A reconstruction with the tibialis tendon was performed by passing the medial third of the tendon from dorsal to plantar through the navicular and from medial to lateral through the calcaneal bone tunnel and securing it to the lateral aspect of the calcaneus. The reconstruction with the tibialis anterior tendon was repeated with the tendon graft routed along the medial aspect of the navicular, directly through the calcaneal bone tunnel. The fourth reconstruction was done with use of an Achilles tendon allograft.(ABSTRACT TRUNCATED AT 250 WORDS)

Dynamic support of the human longitudinal arch. A biomechanical evaluation

This study was designed to evaluate the dynamic support provided to the human longitudinal arch by the leg muscles active in the stance phase of gait and by the plantar aponeurosis. Ten fresh adult cadaveric specimens were mounted in a materials testing machine. The tendons of the posterior tibialis, flexor digitorum longus, flexor hallucis longus, peroneus longus, peroneus brevis, and Achilles tendon were attached to force transducers. Plantar loads of 0, 350 and 700 N were applied, and the tendons were tensioned individually. The Achilles tendon was tensioned an amount equal to the plantar load; the posterior tibialis, flexor digitorum longus, flexor hallucis longus, peroneus longus, and peroneus brevis were tensioned a fractional amount (depending on the proportion of the cross-sectional area to the gastrocsoleus complex). The angular relationships between the first metatarsal, navicular, and talus were recorded using a 3-dimensional movement analysis system. An additional series of measurements was obtained by positioning the ankle plantarflexed 10 degrees under a plantar load of 350 N. Dorsiflexing the toes with the ankle in a neutral position and loading the foot to 350 N and 700 N permitted an evaluation of the effect of the plantar aponeurosis. The plantar aponeurosis, via dorsiflexion of the toes, contributed the most significant arch support in the sagittal plane with a 3.6 degrees increase between the first metatarsal and talus at 350 N and a 2.3 degrees increase at 700 N. The posterior tibialis tendon consistently provided arch support at plantar loads of 350 N and 700 N. The peroneus longus consistently abducted the forefoot in the transverse plane at 350-N and 700-N load levels. The study provides further insight into the dynamic supporting and deforming forces of the longitudinal arch.

Results of bone grafting for infected tibial nonunion

Thirty-two patients with infected tibial nonunions were treated, including 24 men and 8 women whose ages ranged from 21 to 72 years (mean, 40 years). Thirty of 32 patients had bone defects < 3 cm. Using the Cierney-Mader classification of osteomyelitis, 11 of 32 (35%) patients were Stage 4A, and 21 of 32 (65%) patients were Stage 4B. All patients had irrigation, debridement, and stabilization using an external fixation device. Twenty-seven (84%) patients had muscle transfers. The time between initial debridement and muscle transfer ranged from 3 to 24 days (mean, 4 days). Bone grafting was performed between 6 weeks and 8 months (mean, 8 weeks) after soft tissue coverage. Patients received intravenous antibiotics for 2 to 6 weeks (mean, 6 weeks). Twenty patients received anterior grafting, 10 received posterolateral grafting, and 2 received both. Followup times ranged from 12 to 49 months (mean, 28 months). Twenty-nine of the 32 (91%) patients had tibial unions between 3 to 10 months (mean, 5.5 months) after bone grafting. The 3 failed tibias united after posterolateral grafting. Infection was controlled in all 32 patients. Autogenous cancellous bone grafting using infection control principles is an effective means to treat infected tibial nonunions.