The content and accuracy of radiographic interpretations by radiologists was assessed to determin... more The content and accuracy of radiographic interpretations by radiologists was assessed to determine the reports' ability to provide sufficient information necessary to make clinical treatment decisions. A retrospective review was performed of 371 radiographic studies (211 consecutive patients) and their reports which had been generated by three Board-certified radiologists. Data were collected regarding fracture assessment and description as well as the description and assessment of orthopedic implants. These descriptions were categorized by their ability to be used clinically (precise) or not (general). Fracture descriptions were considered complete for 85% of reports, while their assessment of alignment and displacement (necessary to determine fracture care) was complete on only 9%. Orthopedic implants were described precisely on 12% of reports with 7% of the descriptions in error. The effect and position of orthopedic implants were described precisely for only 27% and 25% of cases, respectively, while implant stability was assessed precisely in only 4% of cases. For 61% of preoperative studies, the radiologist's report was not available until after the surgical procedure had already been performed. For all variables considered, an average of 3% of descriptions contained an error. Radiologists' reports of radiographs of these patients undergoing orthopedic procedures did not contain sufficient descriptive information to be used clinically, were not promptly available, and contained an error for 3% of variables studied. The attending orthopedic surgeon has traditionally interpreted such radiographs and should continue to do so to provide patients with more immediate and complete clinical evaluation and management.
The Journal of Heart and Lung Transplantation, 2017
Purpose: Limited data exist evaluating the impact of anemia pre-durable mechanical circulatory su... more Purpose: Limited data exist evaluating the impact of anemia pre-durable mechanical circulatory support devices (MCSDs) on post-MCSD survival. Methods: We performed post-hoc analysis of 302 patients undergoing durable MCSD implantation between April 2009 and august 2016 in this single center study. Pre-MCSD hemoglobin (Hgb) was analyzed as both continuous and categorical variables. Pre-MCSD anemia was defined as blood hemoglobin (Hgb) level < 13 g/dL for male and < 12 g/dL for female. Kaplan-Meier survival estimates were compared using log-rank test for those with and without anemia. Cox-proportional hazard analyses were performed to assess relationship between anemia and post-MCSD mortality. Results: Anemia was highly prevalent at baseline (69.9%). Those with anemia were more likely to have lower body mass index (kg/m 2 ; 28.8±5.6 versus (vs) 30.4±6.0), ischemic heart failure (52.1% vs 37.4%) and on intra-aortic balloon pump (22.3% vs 12.1%) at the time of MCSD implantation (p< 0.05 for all). Total of 83 deaths were observed over median follow up of 1 year. In the adjusted analysis, those with anemia were at significantly higher risk of post-MCSD mortality (see table 1 and figure 1) Conclusion: Pre-MCSD anemia was identified as significant risk marker for post-MCSD mortality. Future studies are required to assess impact of interventions aimed at correcting anemia and their relationship with post-MCSD mortality.
Seminars in cardiothoracic and vascular anesthesia, 2010
Thyroid or parathyroid surgery may be performed using general anesthesia or regional anesthesia. ... more Thyroid or parathyroid surgery may be performed using general anesthesia or regional anesthesia. Ninety-five (95) patients underwent thyroid or parathyroid surgery using general anesthesia (n=64) or bilateral superficial cervical plexus block with sedation (n=31) and completed a postoperative questionnaire regarding the perioperative experience. Patients undergoing parathyroid surgery under regional anesthesia (n=24) were more likely to experience better energy levels (p=0.012) and earlier return to work (p=0.045) postoperatively. Overall, 96% of patients undergoing either type of surgery with either type of anesthetic reported satisfaction with the anesthetic.
The Journal of pharmacology and experimental therapeutics, 1998
We examined the protective effects of GM2941, a sulfated glycomimetic of the complex carbohydrate... more We examined the protective effects of GM2941, a sulfated glycomimetic of the complex carbohydrate sialyl Lewis(x), in a model of pulmonary granuloma development. This study was based on the rationale that formation of glucan-induced lung granulomas is dependent on neutrophils and that sialyl Lewis(x) glycomimetic (GM2941) interferes, in vitro, with P-selectin-dependent neutrophil-endothelial adhesive interactions. Infusion of particulate yeast cell wall glucan into rats results in the rapid (48 hr) formation of monocyte/macrophage-rich angiocentric pulmonary granulomas. Development of granulomas exhibits a temporal pattern characterized by the early, transient influx of neutrophils into blood vessel walls at sites of glucan embolization, followed by accumulation of monocytes and macrophages that constitute the definitive angiocentric lesions. Within 1 hr after the infusion of glucan, immunohistochemical analysis revealed up-regulation of blood vessel wall-associated P-selectin. Prev...
During the last 20 years, asymptomatic patients with high-grade carotid stenosis have been treate... more During the last 20 years, asymptomatic patients with high-grade carotid stenosis have been treated with carotid endarterectomy and more recently with carotid artery stenting in order to prevent stroke. New, best medical treatment including statins, beta-blockers, antiplatelet therapies, and better diabetes and blood pressure control might reduce the incidence of stroke in this patient population making invasive treatment unnecessary. However, patients with asymptomatic carotid stenosis cannot be considered a homogenous population, and therefore, the therapeutic approach should take into consideration a subgroup of patients with greater risk of cerebrovascular event. Unfortunately, these risk factors are not well categorized thus far, although multiple publications have addressed each one of these factors individually. Recognizing these risk factors is essential for optimizing surveillance and therapeutic approach based on individual risk. The purpose of this article is to review suc...
This article, written by Assistant Technology Editor Karen Bybee, contains highlights of paper SP... more This article, written by Assistant Technology Editor Karen Bybee, contains highlights of paper SPE 83978, "Promoting Real-Time Optimization of Hydrocarbon Producing Systems," by L.A. Saputelli, SPE, U. of Houston; S. Mochizuki, ExxonMobil; L. Hutchins, SPE, BP; R. Cramer, SPE, Shell; M.B. Anderson, SPE, and J.B. Mueller, SPE, Schlumberger; A. Escorcia, SPE, Halliburton; A.L. Harms, SPE, ConocoPhillips; C.D. Sisk, SPE, BP; S. Pennebaker, SPE, Baker Hughes; J.T. Han, SPE, Welldynamics; A. Brown, SPE, EPS; C.S. Kabir, SPE, ChevronTexaco; R.D. Reese, SPE, Case Services; G.J. Nunez, SPE, ITSVE; K.M. Landgren, SPE, Schlumberger; and C.J. McKie, SPE, and C. Airlie, EPS, prepared for the 2003 Offshore Europe, Aberdeen, 2-5 September.
Irradiation of etiolated Arabidopsis or pea, or dim-red-light-grown pea seedlings with a single, ... more Irradiation of etiolated Arabidopsis or pea, or dim-red-light-grown pea seedlings with a single, short (under 10 s) pulse of blue light (threshold at 0.1 µmol/m2) is sufficient to induce the expression of specific members of the Lhcb gene family including the pea Lhcb1*4 gene and the Arabidopsis Lhcb1*3 gene. Other Lhcb genes, such as the pea Lhcb1*3 gene and the
Pea seedlings grown in continuous red light accumulate significant levels of Lhcb1 RNA. When trea... more Pea seedlings grown in continuous red light accumulate significant levels of Lhcb1 RNA. When treated with a single pulse of blue light with a total fluence Ͼ 10 4 mol m ؊ 2 , the rate of Lhcb1 transcription is increased, whereas the level of Lhcb1 RNA is unchanged from that in control seedlings. This RNA destabilization response occurs in developing leaves but not in the apical bud. The data presented here indicate that the same response occurs in the cotyledons of etiolated Arabidopsis seedlings. The blue light-induced destabilization response persists in long hypocotyl hy4 and phytochrome phyA , phyB , and hy1 mutants as well as in far-red light-grown seedlings, indicating that neither CRY1 (encoded by the hy4 locus) nor phytochrome is the sole photoreceptor. Studies with transgenic plants indicate that the destabilization element in the pea Lhcb1*4 transcript resides completely in the 5 Ј untranslated region.
Abstract Three methods for the regeneration of α-sulfonyl anions from α-silyl sulfones and α-stan... more Abstract Three methods for the regeneration of α-sulfonyl anions from α-silyl sulfones and α-stannyl sulfones are investigated. These methods include: (1) treatment of α-silyl sulfones with electrophiles (aldehydes and acid halides) in the presence of fluoride ion; (2) reaction of α-silyl sulfones with n-butyllithium which produces an α-silyl anion via a migration of the -SiMe3 group from the α-position to the ortho-position of the phenyl sulfones; and (3) direct transmetalation of α-stannyl sulfone by treatment with n-butyllithium. The addition of cerium [III] chloride is shown to substantially decrease enolization problems associated with addition of α-sulfonyl anions to carbonyl compounds bearing enolizable protons.
The purpose of this study was to determine if toxic effects of cobalt on the murine testis could ... more The purpose of this study was to determine if toxic effects of cobalt on the murine testis could be prevented by zinc, an essential metal for spermatogenesis. CD-1 male mice were administered one of the following in their drinking water: 1) 400 ppm CoC12, 2) 800 ppm ZnCI~, 3) 400 ppm CoCI: + 800 ppm ZnCi2, or 4) distilled water. After 13 weeks, animals were sacrificed and testes were excised, weighed, and processed for histologic study. Comparison of testicular weights revealed no difference between the control and zinc-treated groups, while there was a small but significant reduction in the zinc/cobalt-treated group, and a large reduction in the cobalttreated group. Histologic evaluation of testes confirmed the degenerative effects of cobalt, as well as the normal morphology in the zinc-treated group. Furthermore, 900/o of the animals in the zinc/cobalt-treated group exhibited complete or partial protection as demonstrated by tubular morphology. This study indicates that zinc prevents cobalt-induced testicular damage.
Many complex dynamical systems in ecology, economics, neurology, and elsewhere, in which agents c... more Many complex dynamical systems in ecology, economics, neurology, and elsewhere, in which agents compete for limited resources, exhibit apparently chaotic fluctuations. This Letter proposes a purely deterministic mechanism for evolving robustly but weakly chaotic systems that exhibit adaptation, self-organization, sporadic volatility, and punctuated equilibria.
Gonadal cysts of spotted gar (Lepisosteus oculatus), an air-breathing teleost commonly found in L... more Gonadal cysts of spotted gar (Lepisosteus oculatus), an air-breathing teleost commonly found in Louisiana waters, are described. Fish were collected from two sites: Bayou Trepagnier, a petroleum-contaminated site (30 males and 42 females), and Bayou Traverse, a control site (17 males and 15 females). After ®sh were evaluated for gross abnormalities, they were necropsied and the gonads, gonadal ducts, and gonadal cysts were evaluated histologically. Multilocular¯uid-®lled cysts were noted in the testes, or spermatic ducts of four spotted gars from the Bayou Trepagnier. Unilateral ovarian cystadenomas were present in one female from Bayou Trepagnier. No cysts were observed in the gonads of spotted gar from the control site.
Cardiac surgery is perceived to be maximally invasive and fraught with complications. Secondary t... more Cardiac surgery is perceived to be maximally invasive and fraught with complications. Secondary to this, cardiothoracic surgeons have been re®ning traditional techniques to minimize their invasive nature. Epidural anesthesia has been utilized safely and effectively for numerous surgical procedures to reduce the associated morbidity. In hopes of achieving a similar result, we utilized thoracic epidural anesthesia for a coronary artery bypass via a left anterior thoracotomy, in an awake, spontaneously breathing patient. To the best of our knowledge, this is the ®rst reported case utilizing this approach. Herein we report the results and technique utilized.
Red swamp crayfish (Procambarus clarkii) were placed for a period of 7 days in Bayou Trepagnier, ... more Red swamp crayfish (Procambarus clarkii) were placed for a period of 7 days in Bayou Trepagnier, a Louisiana waterway which received petroleum-laden effluents from a manufacturing complex several decades ago. However, coolant water from the plant continued to be released into the bayou until 1995. Analyses of sediments at the exposure site revealed heavy contamination by lead, chromium, and copper, while concentrations of arsenic and cadmium were very low. Significant bioaccumulation of lead was observed in the hepatopancreas and gills of 7-day-exposed crayfish, whereas chromium accumulated the most in the gills and blood. Concentrations of copper in the crayfish did not change during the course of the study, suggesting that this essential metal constituent of the respiratory pigment is successfully regulated even when crayfish are exposed to relatively high levels of copper in the sediments. There was no metal accumulation in the abdominal muscle of the crayfish. That damage to the hepatopancreas occurred during the exposure is suggested by histopathological studies which revealed swollen and vacuolated R cells and an increase in the pH of the digestive juices. Blood glucose levels, as well as ovarian and hepatopancreatic indices, were unchanged. This study demonstrates that accumulation of nonessential metals in crayfish tissues in a wetland environment contaminated by mixed pollution (metals and hydrocarbons) reflects the concentrations of metals in the sediment.
Our laboratory has demonstrated that treatment of MCF-7 breast cancer cells with melatonin (Mlt) ... more Our laboratory has demonstrated that treatment of MCF-7 breast cancer cells with melatonin (Mlt) followed 24 h later with physiological concentrations of all-trans retinoic acid (atRA) results in apoptosis. These studies were extended into trials using the N-nitroso-N-methylurea (NMU)-induced rat mammary tumor model. Initial studies conducted by feeding the animals 9-cis-retinoic acid (9cRA in the chow) and administering melatonin by subcutaneous injection in the late afternoon demonstrated that the combination of Mlt and 9cRA was able to significantly prevent tumor development, and that the combination was more efficacious that either Mlt or 9cRA alone. In this report, we conducted studies to determine if lower doses of 9cRA could be used in combination with Mlt while still maintaining anti-tumor activity and if the route of administration of 9cRA (bolus (gavage) v.s. chronic (chow) routes) affected its interaction with Mlt. The studies presented here demonstrate that significantly reduced doses of 9cRA can be used in combination with Mlt while maintaining anti-tumor efficacy. Furthermore, our studies demonstrate that 9cRA is equally effective when it is administered chronically (chow) or as a bolus (gavage). These data demonstrate that the combined use of Mlt and 9cRA produces additive or synergistic effects, which are more efficacious than 9cRA alone. This combination of Mlt and 9cRA could be a potentially useful clinical treatment regimen for breast cancer since it allows the use of lower doses of retinoic acid, thus, avoiding the toxic side effects associated with the use of high dose retinoids.
The role of strain dierences in cadmium tissue distribution was studied using sensitive (129/J) a... more The role of strain dierences in cadmium tissue distribution was studied using sensitive (129/J) and resistant (A/J) mice. These murine strains have previously been shown to dier in their susceptibility to cadmium-induced testicular toxicity. Cadmium concentration was measured in testis, epididymis, seminal vesicle, liver, and kidney at 24 h after cadmium chloride exposure (4, 10, and 20 lmol/kg CdCl 2). The 129/J mice exhibited a signi®cant increase in cadmium concentration in testis, epididymis, and seminal vesicle at all cadmium doses used, compared to A/J mice. However, cadmium concentrations in liver and kidney were not dierent between the strains, at any dose, indicating that cadmium uptake is similar in these organs at 24 h. These murine strains demonstrate similar hepatic and renal cadmium uptake but signi®cantly dierent cadmium accumulation in the reproductive organs at 24 h. The mechanism of the protective eect of zinc on cadmium toxicity was studied by assessing the impact of zinc acetate (ZnAc) treatment on cadmium concentrations in 129/J mice after 24 h. Zinc pretreatment (250 lmol/kg ZnAc), given 24 h prior to 20 lmol/kg CdCl 2 administration, signi®cantly decreased the amount of cadmium in the testis, epididymis, and seminal vesicle of 129/J mice, and signi®cantly increased the cadmium content of the liver after 24 h. Cadmium levels in the kidney were unaected at this time. Zinc pretreatment also prevented the cadmium-induced decrease in testicular sperm concentration and epididymal sperm motility seen in 129/J mice. These ®ndings suggest that the dierences in the two murine strains may be attributed partly to the differential accumulation of cadmium in murine gonads. This may be caused by strain dierences in the speci®city of cadmium transport mechanisms. The protective role of zinc in cadmium-induced testicular toxicity in the sensitive strain may be due to an interference in the cadmium uptake by susceptible reproductive organs.
The content and accuracy of radiographic interpretations by radiologists was assessed to determin... more The content and accuracy of radiographic interpretations by radiologists was assessed to determine the reports&#39; ability to provide sufficient information necessary to make clinical treatment decisions. A retrospective review was performed of 371 radiographic studies (211 consecutive patients) and their reports which had been generated by three Board-certified radiologists. Data were collected regarding fracture assessment and description as well as the description and assessment of orthopedic implants. These descriptions were categorized by their ability to be used clinically (precise) or not (general). Fracture descriptions were considered complete for 85% of reports, while their assessment of alignment and displacement (necessary to determine fracture care) was complete on only 9%. Orthopedic implants were described precisely on 12% of reports with 7% of the descriptions in error. The effect and position of orthopedic implants were described precisely for only 27% and 25% of cases, respectively, while implant stability was assessed precisely in only 4% of cases. For 61% of preoperative studies, the radiologist&#39;s report was not available until after the surgical procedure had already been performed. For all variables considered, an average of 3% of descriptions contained an error. Radiologists&#39; reports of radiographs of these patients undergoing orthopedic procedures did not contain sufficient descriptive information to be used clinically, were not promptly available, and contained an error for 3% of variables studied. The attending orthopedic surgeon has traditionally interpreted such radiographs and should continue to do so to provide patients with more immediate and complete clinical evaluation and management.
The Journal of Heart and Lung Transplantation, 2017
Purpose: Limited data exist evaluating the impact of anemia pre-durable mechanical circulatory su... more Purpose: Limited data exist evaluating the impact of anemia pre-durable mechanical circulatory support devices (MCSDs) on post-MCSD survival. Methods: We performed post-hoc analysis of 302 patients undergoing durable MCSD implantation between April 2009 and august 2016 in this single center study. Pre-MCSD hemoglobin (Hgb) was analyzed as both continuous and categorical variables. Pre-MCSD anemia was defined as blood hemoglobin (Hgb) level < 13 g/dL for male and < 12 g/dL for female. Kaplan-Meier survival estimates were compared using log-rank test for those with and without anemia. Cox-proportional hazard analyses were performed to assess relationship between anemia and post-MCSD mortality. Results: Anemia was highly prevalent at baseline (69.9%). Those with anemia were more likely to have lower body mass index (kg/m 2 ; 28.8±5.6 versus (vs) 30.4±6.0), ischemic heart failure (52.1% vs 37.4%) and on intra-aortic balloon pump (22.3% vs 12.1%) at the time of MCSD implantation (p< 0.05 for all). Total of 83 deaths were observed over median follow up of 1 year. In the adjusted analysis, those with anemia were at significantly higher risk of post-MCSD mortality (see table 1 and figure 1) Conclusion: Pre-MCSD anemia was identified as significant risk marker for post-MCSD mortality. Future studies are required to assess impact of interventions aimed at correcting anemia and their relationship with post-MCSD mortality.
Seminars in cardiothoracic and vascular anesthesia, 2010
Thyroid or parathyroid surgery may be performed using general anesthesia or regional anesthesia. ... more Thyroid or parathyroid surgery may be performed using general anesthesia or regional anesthesia. Ninety-five (95) patients underwent thyroid or parathyroid surgery using general anesthesia (n=64) or bilateral superficial cervical plexus block with sedation (n=31) and completed a postoperative questionnaire regarding the perioperative experience. Patients undergoing parathyroid surgery under regional anesthesia (n=24) were more likely to experience better energy levels (p=0.012) and earlier return to work (p=0.045) postoperatively. Overall, 96% of patients undergoing either type of surgery with either type of anesthetic reported satisfaction with the anesthetic.
The Journal of pharmacology and experimental therapeutics, 1998
We examined the protective effects of GM2941, a sulfated glycomimetic of the complex carbohydrate... more We examined the protective effects of GM2941, a sulfated glycomimetic of the complex carbohydrate sialyl Lewis(x), in a model of pulmonary granuloma development. This study was based on the rationale that formation of glucan-induced lung granulomas is dependent on neutrophils and that sialyl Lewis(x) glycomimetic (GM2941) interferes, in vitro, with P-selectin-dependent neutrophil-endothelial adhesive interactions. Infusion of particulate yeast cell wall glucan into rats results in the rapid (48 hr) formation of monocyte/macrophage-rich angiocentric pulmonary granulomas. Development of granulomas exhibits a temporal pattern characterized by the early, transient influx of neutrophils into blood vessel walls at sites of glucan embolization, followed by accumulation of monocytes and macrophages that constitute the definitive angiocentric lesions. Within 1 hr after the infusion of glucan, immunohistochemical analysis revealed up-regulation of blood vessel wall-associated P-selectin. Prev...
During the last 20 years, asymptomatic patients with high-grade carotid stenosis have been treate... more During the last 20 years, asymptomatic patients with high-grade carotid stenosis have been treated with carotid endarterectomy and more recently with carotid artery stenting in order to prevent stroke. New, best medical treatment including statins, beta-blockers, antiplatelet therapies, and better diabetes and blood pressure control might reduce the incidence of stroke in this patient population making invasive treatment unnecessary. However, patients with asymptomatic carotid stenosis cannot be considered a homogenous population, and therefore, the therapeutic approach should take into consideration a subgroup of patients with greater risk of cerebrovascular event. Unfortunately, these risk factors are not well categorized thus far, although multiple publications have addressed each one of these factors individually. Recognizing these risk factors is essential for optimizing surveillance and therapeutic approach based on individual risk. The purpose of this article is to review suc...
This article, written by Assistant Technology Editor Karen Bybee, contains highlights of paper SP... more This article, written by Assistant Technology Editor Karen Bybee, contains highlights of paper SPE 83978, "Promoting Real-Time Optimization of Hydrocarbon Producing Systems," by L.A. Saputelli, SPE, U. of Houston; S. Mochizuki, ExxonMobil; L. Hutchins, SPE, BP; R. Cramer, SPE, Shell; M.B. Anderson, SPE, and J.B. Mueller, SPE, Schlumberger; A. Escorcia, SPE, Halliburton; A.L. Harms, SPE, ConocoPhillips; C.D. Sisk, SPE, BP; S. Pennebaker, SPE, Baker Hughes; J.T. Han, SPE, Welldynamics; A. Brown, SPE, EPS; C.S. Kabir, SPE, ChevronTexaco; R.D. Reese, SPE, Case Services; G.J. Nunez, SPE, ITSVE; K.M. Landgren, SPE, Schlumberger; and C.J. McKie, SPE, and C. Airlie, EPS, prepared for the 2003 Offshore Europe, Aberdeen, 2-5 September.
Irradiation of etiolated Arabidopsis or pea, or dim-red-light-grown pea seedlings with a single, ... more Irradiation of etiolated Arabidopsis or pea, or dim-red-light-grown pea seedlings with a single, short (under 10 s) pulse of blue light (threshold at 0.1 µmol/m2) is sufficient to induce the expression of specific members of the Lhcb gene family including the pea Lhcb1*4 gene and the Arabidopsis Lhcb1*3 gene. Other Lhcb genes, such as the pea Lhcb1*3 gene and the
Pea seedlings grown in continuous red light accumulate significant levels of Lhcb1 RNA. When trea... more Pea seedlings grown in continuous red light accumulate significant levels of Lhcb1 RNA. When treated with a single pulse of blue light with a total fluence Ͼ 10 4 mol m ؊ 2 , the rate of Lhcb1 transcription is increased, whereas the level of Lhcb1 RNA is unchanged from that in control seedlings. This RNA destabilization response occurs in developing leaves but not in the apical bud. The data presented here indicate that the same response occurs in the cotyledons of etiolated Arabidopsis seedlings. The blue light-induced destabilization response persists in long hypocotyl hy4 and phytochrome phyA , phyB , and hy1 mutants as well as in far-red light-grown seedlings, indicating that neither CRY1 (encoded by the hy4 locus) nor phytochrome is the sole photoreceptor. Studies with transgenic plants indicate that the destabilization element in the pea Lhcb1*4 transcript resides completely in the 5 Ј untranslated region.
Abstract Three methods for the regeneration of α-sulfonyl anions from α-silyl sulfones and α-stan... more Abstract Three methods for the regeneration of α-sulfonyl anions from α-silyl sulfones and α-stannyl sulfones are investigated. These methods include: (1) treatment of α-silyl sulfones with electrophiles (aldehydes and acid halides) in the presence of fluoride ion; (2) reaction of α-silyl sulfones with n-butyllithium which produces an α-silyl anion via a migration of the -SiMe3 group from the α-position to the ortho-position of the phenyl sulfones; and (3) direct transmetalation of α-stannyl sulfone by treatment with n-butyllithium. The addition of cerium [III] chloride is shown to substantially decrease enolization problems associated with addition of α-sulfonyl anions to carbonyl compounds bearing enolizable protons.
The purpose of this study was to determine if toxic effects of cobalt on the murine testis could ... more The purpose of this study was to determine if toxic effects of cobalt on the murine testis could be prevented by zinc, an essential metal for spermatogenesis. CD-1 male mice were administered one of the following in their drinking water: 1) 400 ppm CoC12, 2) 800 ppm ZnCI~, 3) 400 ppm CoCI: + 800 ppm ZnCi2, or 4) distilled water. After 13 weeks, animals were sacrificed and testes were excised, weighed, and processed for histologic study. Comparison of testicular weights revealed no difference between the control and zinc-treated groups, while there was a small but significant reduction in the zinc/cobalt-treated group, and a large reduction in the cobalttreated group. Histologic evaluation of testes confirmed the degenerative effects of cobalt, as well as the normal morphology in the zinc-treated group. Furthermore, 900/o of the animals in the zinc/cobalt-treated group exhibited complete or partial protection as demonstrated by tubular morphology. This study indicates that zinc prevents cobalt-induced testicular damage.
Many complex dynamical systems in ecology, economics, neurology, and elsewhere, in which agents c... more Many complex dynamical systems in ecology, economics, neurology, and elsewhere, in which agents compete for limited resources, exhibit apparently chaotic fluctuations. This Letter proposes a purely deterministic mechanism for evolving robustly but weakly chaotic systems that exhibit adaptation, self-organization, sporadic volatility, and punctuated equilibria.
Gonadal cysts of spotted gar (Lepisosteus oculatus), an air-breathing teleost commonly found in L... more Gonadal cysts of spotted gar (Lepisosteus oculatus), an air-breathing teleost commonly found in Louisiana waters, are described. Fish were collected from two sites: Bayou Trepagnier, a petroleum-contaminated site (30 males and 42 females), and Bayou Traverse, a control site (17 males and 15 females). After ®sh were evaluated for gross abnormalities, they were necropsied and the gonads, gonadal ducts, and gonadal cysts were evaluated histologically. Multilocular¯uid-®lled cysts were noted in the testes, or spermatic ducts of four spotted gars from the Bayou Trepagnier. Unilateral ovarian cystadenomas were present in one female from Bayou Trepagnier. No cysts were observed in the gonads of spotted gar from the control site.
Cardiac surgery is perceived to be maximally invasive and fraught with complications. Secondary t... more Cardiac surgery is perceived to be maximally invasive and fraught with complications. Secondary to this, cardiothoracic surgeons have been re®ning traditional techniques to minimize their invasive nature. Epidural anesthesia has been utilized safely and effectively for numerous surgical procedures to reduce the associated morbidity. In hopes of achieving a similar result, we utilized thoracic epidural anesthesia for a coronary artery bypass via a left anterior thoracotomy, in an awake, spontaneously breathing patient. To the best of our knowledge, this is the ®rst reported case utilizing this approach. Herein we report the results and technique utilized.
Red swamp crayfish (Procambarus clarkii) were placed for a period of 7 days in Bayou Trepagnier, ... more Red swamp crayfish (Procambarus clarkii) were placed for a period of 7 days in Bayou Trepagnier, a Louisiana waterway which received petroleum-laden effluents from a manufacturing complex several decades ago. However, coolant water from the plant continued to be released into the bayou until 1995. Analyses of sediments at the exposure site revealed heavy contamination by lead, chromium, and copper, while concentrations of arsenic and cadmium were very low. Significant bioaccumulation of lead was observed in the hepatopancreas and gills of 7-day-exposed crayfish, whereas chromium accumulated the most in the gills and blood. Concentrations of copper in the crayfish did not change during the course of the study, suggesting that this essential metal constituent of the respiratory pigment is successfully regulated even when crayfish are exposed to relatively high levels of copper in the sediments. There was no metal accumulation in the abdominal muscle of the crayfish. That damage to the hepatopancreas occurred during the exposure is suggested by histopathological studies which revealed swollen and vacuolated R cells and an increase in the pH of the digestive juices. Blood glucose levels, as well as ovarian and hepatopancreatic indices, were unchanged. This study demonstrates that accumulation of nonessential metals in crayfish tissues in a wetland environment contaminated by mixed pollution (metals and hydrocarbons) reflects the concentrations of metals in the sediment.
Our laboratory has demonstrated that treatment of MCF-7 breast cancer cells with melatonin (Mlt) ... more Our laboratory has demonstrated that treatment of MCF-7 breast cancer cells with melatonin (Mlt) followed 24 h later with physiological concentrations of all-trans retinoic acid (atRA) results in apoptosis. These studies were extended into trials using the N-nitroso-N-methylurea (NMU)-induced rat mammary tumor model. Initial studies conducted by feeding the animals 9-cis-retinoic acid (9cRA in the chow) and administering melatonin by subcutaneous injection in the late afternoon demonstrated that the combination of Mlt and 9cRA was able to significantly prevent tumor development, and that the combination was more efficacious that either Mlt or 9cRA alone. In this report, we conducted studies to determine if lower doses of 9cRA could be used in combination with Mlt while still maintaining anti-tumor activity and if the route of administration of 9cRA (bolus (gavage) v.s. chronic (chow) routes) affected its interaction with Mlt. The studies presented here demonstrate that significantly reduced doses of 9cRA can be used in combination with Mlt while maintaining anti-tumor efficacy. Furthermore, our studies demonstrate that 9cRA is equally effective when it is administered chronically (chow) or as a bolus (gavage). These data demonstrate that the combined use of Mlt and 9cRA produces additive or synergistic effects, which are more efficacious than 9cRA alone. This combination of Mlt and 9cRA could be a potentially useful clinical treatment regimen for breast cancer since it allows the use of lower doses of retinoic acid, thus, avoiding the toxic side effects associated with the use of high dose retinoids.
The role of strain dierences in cadmium tissue distribution was studied using sensitive (129/J) a... more The role of strain dierences in cadmium tissue distribution was studied using sensitive (129/J) and resistant (A/J) mice. These murine strains have previously been shown to dier in their susceptibility to cadmium-induced testicular toxicity. Cadmium concentration was measured in testis, epididymis, seminal vesicle, liver, and kidney at 24 h after cadmium chloride exposure (4, 10, and 20 lmol/kg CdCl 2). The 129/J mice exhibited a signi®cant increase in cadmium concentration in testis, epididymis, and seminal vesicle at all cadmium doses used, compared to A/J mice. However, cadmium concentrations in liver and kidney were not dierent between the strains, at any dose, indicating that cadmium uptake is similar in these organs at 24 h. These murine strains demonstrate similar hepatic and renal cadmium uptake but signi®cantly dierent cadmium accumulation in the reproductive organs at 24 h. The mechanism of the protective eect of zinc on cadmium toxicity was studied by assessing the impact of zinc acetate (ZnAc) treatment on cadmium concentrations in 129/J mice after 24 h. Zinc pretreatment (250 lmol/kg ZnAc), given 24 h prior to 20 lmol/kg CdCl 2 administration, signi®cantly decreased the amount of cadmium in the testis, epididymis, and seminal vesicle of 129/J mice, and signi®cantly increased the cadmium content of the liver after 24 h. Cadmium levels in the kidney were unaected at this time. Zinc pretreatment also prevented the cadmium-induced decrease in testicular sperm concentration and epididymal sperm motility seen in 129/J mice. These ®ndings suggest that the dierences in the two murine strains may be attributed partly to the differential accumulation of cadmium in murine gonads. This may be caused by strain dierences in the speci®city of cadmium transport mechanisms. The protective role of zinc in cadmium-induced testicular toxicity in the sensitive strain may be due to an interference in the cadmium uptake by susceptible reproductive organs.
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Papers by M.B Anderson