The objective of this study was to determine the effects of transvenous regional guanethidine blo... more The objective of this study was to determine the effects of transvenous regional guanethidine block in the treatment of patients with critical finger ischemia. Twenty-seven patients (17 collagen vascular disease, four thromboangiitis obliterans, three embolism, three atherothrombosis) presenting with ischemic rest pain and/or ulcerations of the fingers received a single block with 5 mg guanethidine injected in 60 mL into the clinically more affected hand under 30 minutes of arterial arrest. Marked hyperemia was induced in the treated upper limb, increases (p < 0.01) in finger blood flow, finger skin temperature, and laser Doppler flux were higher and longer lasting than in forearm blood flow, persisting for a whole month. Effects in patients with ischemic finger ulcers were less pronounced than in those without, yet statistically significant increases of all evaluated parameters were observed in these patients too. No effects were seen in the contralateral untreated upper limb or in systemic blood pressure. Subjective symptoms (reduction of rest pain, numbness, vasospastic attacks) were improved in 25/27 (92.6%) patients, ischemic rest pain disappeared in 20/27 (74.1%), and complete healing of finger tip ulcerations within 1 month was achieved in 10/12 (83.3%) affected patients. No side effects were observed. This described method combines good clinical efficacy with lack of undesirable side effects and can be repeated easily. Therefore, this technique is recommended for broader clinical use.
Choriocarcinoma is a highly malignant tumor of the testis and usually occurs as a component of mi... more Choriocarcinoma is a highly malignant tumor of the testis and usually occurs as a component of mixed germ cell tumor. The testicular enlargement may be subtle, and the patient may present with metastasis, the neck being one of its least reported locations. A case of testicular choriocarcinoma in a 24-year-old man who presented for the first time with metastatic neck mass is reported here. This presentation, although very rare, can be a great diagnostic and therapeutic challenge and should be considered in the differential diagnosis of cervical masses occurring in young males.
The hemodynamic effects of acute mitral regurgitation (MR) were investigated using a newly design... more The hemodynamic effects of acute mitral regurgitation (MR) were investigated using a newly designed adjustable mitral ring prosthesis with remote control mechanism, implanted in mongrel dogs. The prosthesis allows to dilate the mitral annulus from outside the beating heart, and to create reversible MR of any desired degree without injuring the mitral valve apparatus. Dilatation of the mitral annulus by 25% of its circumference led to MR of angiographic grade 3+. Left ventricular systolic pressure (LVSP) dropped by 20%; dp/dtmax of the left ventricle by 16% and forward cardiac output (CO) by 31%. Left ventricular enddiastolic pressure (LVEDP) rose by 41%. The amplitude of the v-wave of the left atrium (LA) doubled, and mean LA pressure rose by 33%. If correction was carried out within one hour, then all parameters returned to normal. Maintaining the same degree of annular dilatation for two hours led to a further marked deterioration of the hemodynamics. LVSP dropped by 40%, dp/dtmax by 32% and CO by 58%. LVEDP rose by 160%. The amplitude of the v-wave of the LA increased by 300% and mean LA pressure doubled. MR, as determined by contrast 2-dimensional echocardiography (2DCE) intraoperatively, further increased in severity during the second hour, though annular size remained unchanged. In contrast to correction after one hour, correction carried out after two hours led to a slow, and, even after 12 hours, incomplete recovery. Electron microscope studies suggest papillary muscle dysfunction as a major cause of these late and partially irreversible changes.
To report procedure-related complications and neurological adverse events of unprotected over-the... more To report procedure-related complications and neurological adverse events of unprotected over-the-wire (OTW) and protected rapid exchange (RX) carotid artery stenting (CAS) in a single-center patient series during an 8-year period. Between 1997 and 2004, 651 consecutive patients (445 men; median age 72 years, interquartile range 64-77) were enrolled in a registry database of carotid stent procedures; from 1997 to 2002, 471 patients underwent unprotected CAS using an OTW technique, while the other 180 patients were treated with protected CAS using RX monorail systems from 2003 to 2004. Technical success and complications (neurological, hemodynamic instability, and access site) up to 30 days post intervention were analyzed. Technical success improved from 95% with unprotected OTW CAS to 99% with protected RX CAS (p=0.025). Procedure-related complications occurred in 86 (18.3%) of 471 unprotected OTW CAS versus 18 (10.0%) of 180 protected RX CAS procedures (p=0.010). Transient ischemic attacks (3.2% versus 2.8%), minor stroke (1.7% versus 0.6%), and major stroke (2.1% versus 0.6%) showed a trend toward a difference between unprotected OTW and protected RX CAS (p=0.076); combined 30-day stroke/death rates were 3.8% for OTW versus 1.2% for RX CAS (p=0.073). During the 8-year period from 1997 to 2004, the annual rates of procedure-related complications (p=0.002), neurological events (p=0.040), and stroke and death (p=0.14) markedly decreased. Carotid stenting became substantially safer in the era of protected RX technology. In addition to a reduction in neurological complications, which may be due to cerebral protection devices, the improved technical success and reduced non-neurological procedure-related complications are likely due to recent technical advances unrelated to cerebral protection.
Abstract—The authors describe the design and performance of an ultrafast optical clock recovery s... more Abstract—The authors describe the design and performance of an ultrafast optical clock recovery system that is based on two-photon absorption (TPA) in a silicon avalanche photodi-ode. Unlike many other optical clock recovery techniques, the system is shown to be polarization ...
Sixty multiparous Holstein-Friesian cows were utilized in a randomized complete block design expe... more Sixty multiparous Holstein-Friesian cows were utilized in a randomized complete block design experiment to evaluate effects of feeding a yeast culture (Saccharomyces cerevisiae), monensin, or both, on their rumen fermentation patterns and performance. The basal diet was a total mixed ration (TMR) containing 383Â g/kg alfalfa hay and 617Â g/kg concentrates (dry matter (DM) basis). Treatments were: (1) control diet (C), (2) control diet plus 2550Â ppm (DM basis) of a yeast culture (YC), (3) control plus 10Â ppm (DM basis) of monensin (M) and (4) control plus 2550Â ppm (DM basis) of a YC plus 10Â ppm (DM basis) of monensin. Cows were fed their TMR twice daily at 07:00 and 16:00Â h from 3 weeks prepartum until 8 weeks postpartum. Cows were milked twice daily at 06:00 and 17:00Â h. Compared to C, all treatments increased mean postpartum ruminal propionate concentration and decreased the ratio of acetate:propionate. Mean postpartum rumen pH and ammonia N concentrations were not affected by treatment, although pH and ammonia N progressively decreased with either YC or M as the level of pH or ammonia N in the cows increased. Mean milk yield, milk composition and body weight change of treatment groups did not differ from those of the C group, although milk crude protein (CP) yield progressively increased with YC, and decreased with M, as the level of milk CP production of the cows increased. Mean DM intake (DMI) varied between 20.8Â kg/day (M) and 22.2Â kg/day (C), with DMI progressively increased with YC, and decreased with M, as the DMI level of the cows increased. Results suggest a modest complimentary effect between YC and M, as YC tended to alleviate the depression in mean DMI caused by M. However, results can also be interpreted to suggest that YC may be a better choice than M in cows with high DMI potential, and/or inherent milk production capability, whereas M may be a better choice than YC in cows with lower DMI potential, and/or inherent milk protein production potential.
Purpose: To investigate initial and long-term success rate after percutaneous treatment of iliac ... more Purpose: To investigate initial and long-term success rate after percutaneous treatment of iliac artery occlusion with angioplasty and stent deployment. To investigate the influence of vascular comorbidity, lesion length, stent placement and lesion coverage as possible predictors of outcome. Methods: Between January 1994 and December 1999, 80 iliac recanalizations were performed on 78 patients, median age 61.1 ± 11.5 (SD) years. All patients were followed up by clinical examinations, duplex ultrasound and intravenous digital subtraction angiography. Mean follow-up time was 2.0 ± 1.53 (SD) years. Multivariate Cox regression analysis was used to determine the influence of cofactors on patency. Results: One, 2 and 4 years after recanalization, primary patency was 78.1%, 74.5% and 64.0%; secondary patency was 88.8%, 88.8% and 77.9%, respectively. Patients with shorter occlusions, complete lesion coverage and patent ipsilateral femoral arteries had significantly longer patency rates. Complications included inguinal hematoma (n=1), technical failure (n=3) aortic dissection (n=1), embolic occlusions (n=7), gluteal claudication (n=1) and genital necrosis after subsequent urethral surgery in one patient with contralateral occlusion and ipsilateral overstenting of the internal iliac artery with subsequent stenosis. Complications were of permanent clinical significance in seven of 78 (9%) of the patients. In 17 (22%) cases, percutaneous reintervention was performed with angioplasty in the stent (n=16) or deployment of a new stent (n=1). Conclusion: Endoluminal stent placement has its place in an interdisciplinary therapeutic approach as a viable therapeutic alternative to major transabdominal bypass surgery and can be performed with comparable complication rates. Patients with short occlusions, patent femoral arteries, and stents covering the entire occlusion have significant longer patency.
Considering the thermodynamic aspects and reaction pathways of chemical adsorption of NH3 molecul... more Considering the thermodynamic aspects and reaction pathways of chemical adsorption of NH3 molecule at the open ends of boron nitride nanotubes (BNNTs), theoretically, it was found that the open-ended BNNTs are able to cleave the N–H bond of NH3 via a one- or two-stepwise mechanism. The N-enriched and B-enriched open-ended BNNTs show a nucleophilic and electrophilic behavior toward the NH3,
... formaldehyde. Ali Ahmadi a , Nasser L. Hadipour a , Corresponding Author Contact Information ... more ... formaldehyde. Ali Ahmadi a , Nasser L. Hadipour a , Corresponding Author Contact Information , E-mail The Corresponding Author , E-mail The Corresponding Author , Mohammad Kamfiroozi b , Zargham Bagheri c. [Author vitae]. ...
The biological control strain Agrobacterium rhizogenes K84 is an effective agent in the control o... more The biological control strain Agrobacterium rhizogenes K84 is an effective agent in the control of Agrobacterium pathogens, the causative agents of crown gall disease. A number of factors are thought to play a role in the control process, including production of the specific agrocins 84 and 434, which differ in the spectra of pathogenic strains that they inhibit in vitro. A range of derivatives of strain K84 has been developed with every combination of the three resident plasmids, pAgK84, pAgK434, and pAtK84b, including a plasmid-free strain. These derivatives produced either both, one, or neither of the characterized agrocins 84 and 434 and were isolated by plasmid curing, conjugation, and Tn5 transposon mutagenesis. The ability of the derivative strains to inhibit gall formation on almond roots was compared to that of the wild-type K84 parent. Treatment with the plasmid-free derivative did not result in a significant level of control of an A. rhizogenes pathogen based on numbers or dry weight of galls formed on injured almond roots. The presence of plasmid pAgK84, pAgK434, or pAtK84b significantly enhanced the biological control efficacy of K84 derivatives, and the highest level of control was observed with strains harboring two or more plasmids. The results observed with strains deficient in agrocin 434 production suggest that this product may play an important role in the biological control of A. rhizogenes pathogens. The involvement of plasmid pAgK84b in biological control has not previously been reported. This study supports the conclusion that multiple factors are involved in the success of strain K84 as a biological control agent.
To develop a technique for the selection of viable sperm for intracytoplasmic sperm injection (IC... more To develop a technique for the selection of viable sperm for intracytoplasmic sperm injection (ICSI), based on the phenomenon of sperm tail curling in a hypo-osmotic environment, through modification of the hypo-osmotic swelling test. Individual sperm were exposed to single sperm curling (SSC) medium and then injected into hamster oocytes to study the effect of SSC medium on fertilization. All materials were collected from the National University Hospital in Singapore. Semen of proven donors and hamster oocytes with intact zonae were used. ICSI and the SSC test. Sperm head decondensation and male pronucleus formation. Sperm head decondensation and male pronucleus formation were present in 59.4% and 42.4%, respectively, of the oocytes injected with sperm that had been exposed to SSC medium. These rates were 70% and 48.8%, respectively, when the sperm were washed thoroughly after exposure to SSC medium. In the control group (sperm that were not exposed to SSC medium), these rates were 68.8% and 46.2%, respectively. The SSC test is useful for the selection of viable sperm for ICSI. It allows the behavioral study of a single sperm in hypo-osmotic conditions. Thorough washing of the exposed sperm is important. This procedure would be of benefit especially in testicular biopsies or very severe cases of low sperm count in which only a few sperm are found among many other cells and artifact.
The objective of this study was to determine the effects of transvenous regional guanethidine blo... more The objective of this study was to determine the effects of transvenous regional guanethidine block in the treatment of patients with critical finger ischemia. Twenty-seven patients (17 collagen vascular disease, four thromboangiitis obliterans, three embolism, three atherothrombosis) presenting with ischemic rest pain and/or ulcerations of the fingers received a single block with 5 mg guanethidine injected in 60 mL into the clinically more affected hand under 30 minutes of arterial arrest. Marked hyperemia was induced in the treated upper limb, increases (p < 0.01) in finger blood flow, finger skin temperature, and laser Doppler flux were higher and longer lasting than in forearm blood flow, persisting for a whole month. Effects in patients with ischemic finger ulcers were less pronounced than in those without, yet statistically significant increases of all evaluated parameters were observed in these patients too. No effects were seen in the contralateral untreated upper limb or in systemic blood pressure. Subjective symptoms (reduction of rest pain, numbness, vasospastic attacks) were improved in 25/27 (92.6%) patients, ischemic rest pain disappeared in 20/27 (74.1%), and complete healing of finger tip ulcerations within 1 month was achieved in 10/12 (83.3%) affected patients. No side effects were observed. This described method combines good clinical efficacy with lack of undesirable side effects and can be repeated easily. Therefore, this technique is recommended for broader clinical use.
Choriocarcinoma is a highly malignant tumor of the testis and usually occurs as a component of mi... more Choriocarcinoma is a highly malignant tumor of the testis and usually occurs as a component of mixed germ cell tumor. The testicular enlargement may be subtle, and the patient may present with metastasis, the neck being one of its least reported locations. A case of testicular choriocarcinoma in a 24-year-old man who presented for the first time with metastatic neck mass is reported here. This presentation, although very rare, can be a great diagnostic and therapeutic challenge and should be considered in the differential diagnosis of cervical masses occurring in young males.
The hemodynamic effects of acute mitral regurgitation (MR) were investigated using a newly design... more The hemodynamic effects of acute mitral regurgitation (MR) were investigated using a newly designed adjustable mitral ring prosthesis with remote control mechanism, implanted in mongrel dogs. The prosthesis allows to dilate the mitral annulus from outside the beating heart, and to create reversible MR of any desired degree without injuring the mitral valve apparatus. Dilatation of the mitral annulus by 25% of its circumference led to MR of angiographic grade 3+. Left ventricular systolic pressure (LVSP) dropped by 20%; dp/dtmax of the left ventricle by 16% and forward cardiac output (CO) by 31%. Left ventricular enddiastolic pressure (LVEDP) rose by 41%. The amplitude of the v-wave of the left atrium (LA) doubled, and mean LA pressure rose by 33%. If correction was carried out within one hour, then all parameters returned to normal. Maintaining the same degree of annular dilatation for two hours led to a further marked deterioration of the hemodynamics. LVSP dropped by 40%, dp/dtmax by 32% and CO by 58%. LVEDP rose by 160%. The amplitude of the v-wave of the LA increased by 300% and mean LA pressure doubled. MR, as determined by contrast 2-dimensional echocardiography (2DCE) intraoperatively, further increased in severity during the second hour, though annular size remained unchanged. In contrast to correction after one hour, correction carried out after two hours led to a slow, and, even after 12 hours, incomplete recovery. Electron microscope studies suggest papillary muscle dysfunction as a major cause of these late and partially irreversible changes.
To report procedure-related complications and neurological adverse events of unprotected over-the... more To report procedure-related complications and neurological adverse events of unprotected over-the-wire (OTW) and protected rapid exchange (RX) carotid artery stenting (CAS) in a single-center patient series during an 8-year period. Between 1997 and 2004, 651 consecutive patients (445 men; median age 72 years, interquartile range 64-77) were enrolled in a registry database of carotid stent procedures; from 1997 to 2002, 471 patients underwent unprotected CAS using an OTW technique, while the other 180 patients were treated with protected CAS using RX monorail systems from 2003 to 2004. Technical success and complications (neurological, hemodynamic instability, and access site) up to 30 days post intervention were analyzed. Technical success improved from 95% with unprotected OTW CAS to 99% with protected RX CAS (p=0.025). Procedure-related complications occurred in 86 (18.3%) of 471 unprotected OTW CAS versus 18 (10.0%) of 180 protected RX CAS procedures (p=0.010). Transient ischemic attacks (3.2% versus 2.8%), minor stroke (1.7% versus 0.6%), and major stroke (2.1% versus 0.6%) showed a trend toward a difference between unprotected OTW and protected RX CAS (p=0.076); combined 30-day stroke/death rates were 3.8% for OTW versus 1.2% for RX CAS (p=0.073). During the 8-year period from 1997 to 2004, the annual rates of procedure-related complications (p=0.002), neurological events (p=0.040), and stroke and death (p=0.14) markedly decreased. Carotid stenting became substantially safer in the era of protected RX technology. In addition to a reduction in neurological complications, which may be due to cerebral protection devices, the improved technical success and reduced non-neurological procedure-related complications are likely due to recent technical advances unrelated to cerebral protection.
Abstract—The authors describe the design and performance of an ultrafast optical clock recovery s... more Abstract—The authors describe the design and performance of an ultrafast optical clock recovery system that is based on two-photon absorption (TPA) in a silicon avalanche photodi-ode. Unlike many other optical clock recovery techniques, the system is shown to be polarization ...
Sixty multiparous Holstein-Friesian cows were utilized in a randomized complete block design expe... more Sixty multiparous Holstein-Friesian cows were utilized in a randomized complete block design experiment to evaluate effects of feeding a yeast culture (Saccharomyces cerevisiae), monensin, or both, on their rumen fermentation patterns and performance. The basal diet was a total mixed ration (TMR) containing 383Â g/kg alfalfa hay and 617Â g/kg concentrates (dry matter (DM) basis). Treatments were: (1) control diet (C), (2) control diet plus 2550Â ppm (DM basis) of a yeast culture (YC), (3) control plus 10Â ppm (DM basis) of monensin (M) and (4) control plus 2550Â ppm (DM basis) of a YC plus 10Â ppm (DM basis) of monensin. Cows were fed their TMR twice daily at 07:00 and 16:00Â h from 3 weeks prepartum until 8 weeks postpartum. Cows were milked twice daily at 06:00 and 17:00Â h. Compared to C, all treatments increased mean postpartum ruminal propionate concentration and decreased the ratio of acetate:propionate. Mean postpartum rumen pH and ammonia N concentrations were not affected by treatment, although pH and ammonia N progressively decreased with either YC or M as the level of pH or ammonia N in the cows increased. Mean milk yield, milk composition and body weight change of treatment groups did not differ from those of the C group, although milk crude protein (CP) yield progressively increased with YC, and decreased with M, as the level of milk CP production of the cows increased. Mean DM intake (DMI) varied between 20.8Â kg/day (M) and 22.2Â kg/day (C), with DMI progressively increased with YC, and decreased with M, as the DMI level of the cows increased. Results suggest a modest complimentary effect between YC and M, as YC tended to alleviate the depression in mean DMI caused by M. However, results can also be interpreted to suggest that YC may be a better choice than M in cows with high DMI potential, and/or inherent milk production capability, whereas M may be a better choice than YC in cows with lower DMI potential, and/or inherent milk protein production potential.
Purpose: To investigate initial and long-term success rate after percutaneous treatment of iliac ... more Purpose: To investigate initial and long-term success rate after percutaneous treatment of iliac artery occlusion with angioplasty and stent deployment. To investigate the influence of vascular comorbidity, lesion length, stent placement and lesion coverage as possible predictors of outcome. Methods: Between January 1994 and December 1999, 80 iliac recanalizations were performed on 78 patients, median age 61.1 ± 11.5 (SD) years. All patients were followed up by clinical examinations, duplex ultrasound and intravenous digital subtraction angiography. Mean follow-up time was 2.0 ± 1.53 (SD) years. Multivariate Cox regression analysis was used to determine the influence of cofactors on patency. Results: One, 2 and 4 years after recanalization, primary patency was 78.1%, 74.5% and 64.0%; secondary patency was 88.8%, 88.8% and 77.9%, respectively. Patients with shorter occlusions, complete lesion coverage and patent ipsilateral femoral arteries had significantly longer patency rates. Complications included inguinal hematoma (n=1), technical failure (n=3) aortic dissection (n=1), embolic occlusions (n=7), gluteal claudication (n=1) and genital necrosis after subsequent urethral surgery in one patient with contralateral occlusion and ipsilateral overstenting of the internal iliac artery with subsequent stenosis. Complications were of permanent clinical significance in seven of 78 (9%) of the patients. In 17 (22%) cases, percutaneous reintervention was performed with angioplasty in the stent (n=16) or deployment of a new stent (n=1). Conclusion: Endoluminal stent placement has its place in an interdisciplinary therapeutic approach as a viable therapeutic alternative to major transabdominal bypass surgery and can be performed with comparable complication rates. Patients with short occlusions, patent femoral arteries, and stents covering the entire occlusion have significant longer patency.
Considering the thermodynamic aspects and reaction pathways of chemical adsorption of NH3 molecul... more Considering the thermodynamic aspects and reaction pathways of chemical adsorption of NH3 molecule at the open ends of boron nitride nanotubes (BNNTs), theoretically, it was found that the open-ended BNNTs are able to cleave the N–H bond of NH3 via a one- or two-stepwise mechanism. The N-enriched and B-enriched open-ended BNNTs show a nucleophilic and electrophilic behavior toward the NH3,
... formaldehyde. Ali Ahmadi a , Nasser L. Hadipour a , Corresponding Author Contact Information ... more ... formaldehyde. Ali Ahmadi a , Nasser L. Hadipour a , Corresponding Author Contact Information , E-mail The Corresponding Author , E-mail The Corresponding Author , Mohammad Kamfiroozi b , Zargham Bagheri c. [Author vitae]. ...
The biological control strain Agrobacterium rhizogenes K84 is an effective agent in the control o... more The biological control strain Agrobacterium rhizogenes K84 is an effective agent in the control of Agrobacterium pathogens, the causative agents of crown gall disease. A number of factors are thought to play a role in the control process, including production of the specific agrocins 84 and 434, which differ in the spectra of pathogenic strains that they inhibit in vitro. A range of derivatives of strain K84 has been developed with every combination of the three resident plasmids, pAgK84, pAgK434, and pAtK84b, including a plasmid-free strain. These derivatives produced either both, one, or neither of the characterized agrocins 84 and 434 and were isolated by plasmid curing, conjugation, and Tn5 transposon mutagenesis. The ability of the derivative strains to inhibit gall formation on almond roots was compared to that of the wild-type K84 parent. Treatment with the plasmid-free derivative did not result in a significant level of control of an A. rhizogenes pathogen based on numbers or dry weight of galls formed on injured almond roots. The presence of plasmid pAgK84, pAgK434, or pAtK84b significantly enhanced the biological control efficacy of K84 derivatives, and the highest level of control was observed with strains harboring two or more plasmids. The results observed with strains deficient in agrocin 434 production suggest that this product may play an important role in the biological control of A. rhizogenes pathogens. The involvement of plasmid pAgK84b in biological control has not previously been reported. This study supports the conclusion that multiple factors are involved in the success of strain K84 as a biological control agent.
To develop a technique for the selection of viable sperm for intracytoplasmic sperm injection (IC... more To develop a technique for the selection of viable sperm for intracytoplasmic sperm injection (ICSI), based on the phenomenon of sperm tail curling in a hypo-osmotic environment, through modification of the hypo-osmotic swelling test. Individual sperm were exposed to single sperm curling (SSC) medium and then injected into hamster oocytes to study the effect of SSC medium on fertilization. All materials were collected from the National University Hospital in Singapore. Semen of proven donors and hamster oocytes with intact zonae were used. ICSI and the SSC test. Sperm head decondensation and male pronucleus formation. Sperm head decondensation and male pronucleus formation were present in 59.4% and 42.4%, respectively, of the oocytes injected with sperm that had been exposed to SSC medium. These rates were 70% and 48.8%, respectively, when the sperm were washed thoroughly after exposure to SSC medium. In the control group (sperm that were not exposed to SSC medium), these rates were 68.8% and 46.2%, respectively. The SSC test is useful for the selection of viable sperm for ICSI. It allows the behavioral study of a single sperm in hypo-osmotic conditions. Thorough washing of the exposed sperm is important. This procedure would be of benefit especially in testicular biopsies or very severe cases of low sperm count in which only a few sperm are found among many other cells and artifact.
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