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1.
Contemp Clin Trials ; 123: 106965, 2022 12.
Article in English | MEDLINE | ID: mdl-36252936

ABSTRACT

BACKGROUND: Nearly 2 million youth seek acute medical care following concussion in the U.S. each year. Current standard of care recommends rest for the first 48 h after a concussion. However, research suggests that prolonged rest may lengthen recovery time especially for patients with certain risk profiles. Research indicates that physical activity and behavioral management interventions (sleep, stress management) may enhance recovery. To date, there is limited empirical evidence to inform acute (<72 h) concussion recommendations for physical activity and behavioral management in adolescents. OBJECTIVE: To determine the effectiveness of physical activity and behavioral management for acute concussion in adolescents and young adults, and to evaluate the role of patient characteristics on treatment response. METHODS: This multicenter prospective randomized controlled trial will determine which combination of physical activity and behavioral management is most effective for patients 11-24 years old who present to the emergency department or concussion clinic within 72 h of injury. Participants are randomized into: 1) rest, 2) physical activity, 3) mobile health application (mHealth) behavioral management, or 4) physical activity and mHealth app conditions. Assessments at enrollment, 3-5 days, 14 days, 1 month, and 2 months include: concussion symptoms, balance, vestibular-ocular and cognitive assessments, quality of life, and recovery time. Somatic symptoms and other risk factors are evaluated at enrollment. Compliance with treatment and symptoms are assessed daily using actigraph and daily self-report. The primary study outcome is symptoms at 14 days. CONCLUSION: Prescribed physical activity and behavioral management may improve outcomes in youth following acute concussion.


Subject(s)
Brain Concussion , Post-Concussion Syndrome , Young Adult , Humans , Adolescent , Child , Adult , Post-Concussion Syndrome/therapy , Post-Concussion Syndrome/diagnosis , Post-Concussion Syndrome/etiology , Prospective Studies , Quality of Life , Brain Concussion/therapy , Exercise
2.
J Dairy Sci ; 101(8): 6730-6741, 2018 Aug.
Article in English | MEDLINE | ID: mdl-29803426

ABSTRACT

Bovine milk glycomacropeptide (GMP) is derived from κ-casein, with exclusively o-linked glycosylation. Glycomacropeptide promoted the growth of Bifidobacterium longum ssp. infantis in a concentration-dependent manner, and this activity was lost following periodate treatment of the GMP (GMP-P), which disables biological recognition of the conjugated oligosaccharides. Transcriptional analysis of B. longum ssp. infantis following exposure to GMP revealed a substantial response to GMP relative to bacteria treated with GMP-P, with a greater number of differentially expressed transcripts and larger fold changes versus the control. Therefore, stimulation of B. longum ssp. infantis growth by GMP is intrinsically linked to the peptide's O-linked glycosylation. The pool of differentially expressed transcripts included 2 glycoside hydrolase (family 25) genes, which were substantially upregulated following exposure to GMP, but not GMP-P. These GH25 genes were present in duplicated genomic islands that also contained genes encoding fibronectin type III binding domain proteins and numerous phage-related proteins, all of which were also upregulated. Homologs of this genomic arrangement were present in other Bifidobacterium species, which suggest it may be a conserved domain for the utilization of glycosylated peptides. This study provides insights into the molecular basis for the prebiotic effect of bovine milk GMP on B. longum ssp. infantis.


Subject(s)
Bifidobacterium longum subspecies infantis/growth & development , Bifidobacterium longum subspecies infantis/genetics , Caseins/pharmacology , Gene Expression Regulation, Bacterial , Peptide Fragments/pharmacology , Animals , Cattle , Oligosaccharides
3.
Biomed Mater ; 11(1): 015014, 2016 Feb 19.
Article in English | MEDLINE | ID: mdl-26894472

ABSTRACT

We show that femtosecond laser irradiation of polydimethylsiloxane (PDMS) enables selective and patterned cell growth by altering the wetting properties of the surface associated with chemical and/or topographical changes. In the low pulse energy regime, the surface becomes less hydrophobic and exhibits a low water contact angle compared to the pristine material. X-ray photoelectron spectroscopy (XPS) also reveals an increased oxygen content in the irradiated regions, to which the C2C12 cells and rabbit anti-mouse protein were found to attach preferentially. In the high pulse energy regime, the laser-modified regions exhibit superhydrophobicity and were found to inhibit cell adhesion, whereas cells were found to attach to the surrounding regions due to the presence of nanoscale debris generated by the ablation process.


Subject(s)
Cell Adhesion/physiology , Dimethylpolysiloxanes/chemistry , Lasers , Molecular Imprinting/methods , Myoblasts/cytology , Myoblasts/physiology , Animals , Biocompatible Materials/chemistry , Biocompatible Materials/radiation effects , Cell Line , Dimethylpolysiloxanes/radiation effects , Materials Testing , Mice , Surface Properties/radiation effects
4.
Cell Death Dis ; 6: e1966, 2015 Nov 05.
Article in English | MEDLINE | ID: mdl-26539913

ABSTRACT

Cyclopentenone prostaglandins (CyPGs), such as 15-deoxy-Δ(12,14)-prostaglandin J2 (15dPGJ2), are reactive prostaglandin metabolites exerting a variety of biological effects. CyPGs are produced in ischemic brain and disrupt the ubiquitin-proteasome system (UPS). Ubiquitin-C-terminal hydrolase L1 (UCH-L1) is a brain-specific deubiquitinating enzyme that has been linked to neurodegenerative diseases. Using tandem mass spectrometry (MS) analyses, we found that the C152 site of UCH-L1 is adducted by CyPGs. Mutation of C152 to alanine (C152A) inhibited CyPG modification and conserved recombinant UCH-L1 protein hydrolase activity after 15dPGJ2 treatment. A knock-in (KI) mouse expressing the UCH-L1 C152A mutation was constructed with the bacterial artificial chromosome (BAC) technique. Brain expression and distribution of UCH-L1 in the KI mouse was similar to that of wild type (WT) as determined by western blotting. Primary cortical neurons derived from KI mice were resistant to 15dPGJ2 cytotoxicity compared with neurons from WT mice as detected by the WST-1 cell viability assay and caspase-3 and poly ADP ribose polymerase (PARP) cleavage. This protective effect was accompanied with significantly less ubiquitinated protein accumulation and aggregation as well as less UCH-L1 aggregation in C152A KI primary neurons after 15dPGJ2 treatment. Additionally, 15dPGJ2-induced axonal injury was also significantly attenuated in KI neurons as compared with WT. Taken together, these studies indicate that UCH-L1 function is important in hypoxic neuronal death, and the C152 site of UCH-L1 has a significant role in neuronal survival after hypoxic/ischemic injury.


Subject(s)
Brain Ischemia/genetics , Cyclopentanes/toxicity , Neurons/drug effects , Neurons/physiology , Point Mutation , Prostaglandins/toxicity , Ubiquitin Thiolesterase/genetics , Animals , Binding Sites , Brain Ischemia/enzymology , Brain Ischemia/pathology , Female , Male , Mice , Mice, Inbred C57BL , Mice, Transgenic , Neurons/enzymology , Neurons/metabolism , Rats , Ubiquitin Thiolesterase/biosynthesis
5.
Can Commun Dis Rep ; 41(Suppl 6): 3-8, 2015 Dec 17.
Article in English | MEDLINE | ID: mdl-29769971

ABSTRACT

BACKGROUND: The global spread of communicable diseases is a growing concern largely as a result of increased international travel. In Canada, although most public health management of communicable diseases occurs at the front line, the federal government also takes actions to prevent and mitigate their importation. OBJECTIVE: To describe the role of the Public Health Agency of Canada (PHAC) in minimizing the importation of communicable diseases through preventive measures taken before travellers leave Canada and through early detection and prompt containment measures taken when travellers arrive in the country with a potential communicable disease. INTERVENTIONS: PHAC works to minimize the importation of communicable diseases into Canada by developing evidence-based travel health advice and targeted outreach activities geared to the public and to health care professionals. On the basis of the Quarantine Act and the International Health Regulations (2005), PHAC also conducts inspections of conveyances such as aircraft and boats and works with partners to conduct border screening to assess ill travellers entering the country. CONCLUSION: PHAC plays an important role in preventing and minimizing the importation of communicable diseases into Canada in conjunction with clinicians, public health authorities at all levels of government and other federal government departments.

6.
BJOG ; 120(6): 695-704; discussion 704-6, 2013 May.
Article in English | MEDLINE | ID: mdl-23398859

ABSTRACT

OBJECTIVE: To investigate the influence of menses on the vaginal microbiota and determine whether tampons that differ in material composition influence these bacterial communities in different ways. DESIGN: A single-centre trial with randomised, complete block design. SETTING: Procter & Gamble facility. SAMPLE: Seven self-declared healthy, female volunteers of reproductive age. METHODS: Volunteers used a pad and two types of tampons during the study, one product exclusively each month for three sequential menstrual cycles. During menses and once each mid-cycle, vaginal bacterial community composition was characterised by cultivation-independent methods based on pyrosequencing of V1-V2 variable regions of 16S ribosomal RNA genes. MAIN OUTCOME MEASURES: Changes in the species composition, abundance and diversity in vaginal bacterial communities over time and between treatments. RESULTS: The vaginal microbiotas of all seven women were dominated by Lactobacillus spp. at mid-cycle, and the compositions of those communities were largely consistent between cycles. Community dynamic patterns during menses varied considerably and were more or less individualised. In three of the seven women the community diversity during pad use was significantly different from at least one tampon cycle. CONCLUSIONS: Changes in the composition of the vaginal microbiota during menses were common, but the magnitude of change varied between women. Despite these changes, most communities were capable of resuming a composition similar to previous mid-cycle sampling times following menstruation. Overall we conclude that the two tampons tested do not significantly impact the vaginal microbiota in different ways; however, larger studies should be performed to confirm these findings.


Subject(s)
Bacteria/classification , Menstrual Hygiene Products , Menstruation , Metagenome , Vagina/microbiology , Adolescent , Adult , Bacteria/genetics , Bacteria/isolation & purification , Female , Humans , Middle Aged , RNA, Ribosomal, 16S/genetics , Sequence Analysis, DNA , Young Adult
7.
Oncogene ; 31(27): 3244-53, 2012 Jul 05.
Article in English | MEDLINE | ID: mdl-22081068

ABSTRACT

Many tumors exhibit elevated chromosome mis-segregation termed chromosome instability (CIN), which is likely to be a potent driver of tumor progression and drug resistance. Causes of CIN are poorly understood but probably include prior genome tetraploidization, centrosome amplification and mitotic checkpoint defects. This study identifies epigenetic alteration of the centromere as a potential contributor to the CIN phenotype. The centromere controls chromosome segregation and consists of higher-order repeat (HOR) alpha-satellite DNA packaged into two chromatin domains: the kinetochore, harboring the centromere-specific H3 variant centromere protein A (CENP-A), and the pericentromeric heterochromatin, considered important for cohesion. Perturbation of centromeric chromatin in model systems causes CIN. As cancer cells exhibit widespread chromatin changes, we hypothesized that pericentromeric chromatin structure could also be affected, contributing to CIN. Cytological and chromatin immunoprecipitation and PCR (ChIP-PCR)-based analyses of HT1080 cancer cells showed that only one of the two HORs on chromosomes 5 and 7 incorporate CENP-A, an organization conserved in all normal and cancer-derived cells examined. Contrastingly, the heterochromatin marker H3K9me3 (trimethylation of H3 lysine 9) mapped to all four HORs and ChIP-PCR showed an altered pattern of H3K9me3 in cancer cell lines and breast tumors, consistent with a reduction on the kinetochore-forming HORs. The JMJD2B demethylase is overexpressed in breast tumors with a CIN phenotype, and overexpression of exogenous JMJD2B in cultured breast epithelial cells caused loss of centromere-associated H3K9me3 and increased CIN. These findings suggest that impaired maintenance of pericentromeric heterochromatin may contribute to CIN in cancer and be a novel therapeutic target.


Subject(s)
Breast Neoplasms/genetics , Breast Neoplasms/metabolism , Centromere/genetics , Centromere/metabolism , Chromosomal Instability , Heterochromatin/metabolism , Breast Neoplasms/pathology , Carcinoma, Ductal, Breast/genetics , Carcinoma, Ductal, Breast/metabolism , Carcinoma, Ductal, Breast/pathology , Cell Line, Tumor , Chromosomes, Human, Pair 5/genetics , Female , Histones/metabolism , Humans , Jumonji Domain-Containing Histone Demethylases/metabolism , Kinetochores/metabolism , Neoplasm Invasiveness
8.
Int J Proteomics ; 2011: 373816, 2011.
Article in English | MEDLINE | ID: mdl-22084686

ABSTRACT

Repair of double-stranded breaks (DSBs) is vital to maintaining genomic stability. In mammalian cells, DSBs are resolved in one of the following complex repair pathways: nonhomologous end-joining (NHEJ), homologous recombination (HR), or the inclusive DNA damage response (DDR). These repair pathways rely on factors that utilize reversible phosphorylation of proteins as molecular switches to regulate DNA repair. Many of these molecular switches overlap and play key roles in multiple pathways. For example, the NHEJ pathway and the DDR both utilize DNA-PK phosphorylation, whereas the HR pathway mediates repair with phosphorylation of RPA2, BRCA1, and BRCA2. Also, the DDR pathway utilizes the kinases ATM and ATR, as well as the phosphorylation of H2AX and MDC1. Together, these molecular switches regulate repair of DSBs by aiding in DSB recognition, pathway initiation, recruitment of repair factors, and the maintenance of repair mechanisms.

9.
J Integr Plant Biol ; 50(6): 653-8, 2008 Jun.
Article in English | MEDLINE | ID: mdl-18713405

ABSTRACT

Herbivory with crypsis is not well documented in ferns. The present record of cryptic coloration of coccid Saissetia filicum Boisduval (Homoptera: Coccidae) to the sori of a fern species Asplenium nidus L. (Aspleniaceae) is unique. Predatory beetles (Jauravia sp., Coleoptera: Coccinellidae) that feed on the coccids, are suggested to be selective pressure for the development of the present homopteran soral crypsis. A higher rate of effective predation is noticed in the vegetative leaves than the fertile leaves. Aggressive ants were found harvesting honeydew secretions from the coccids and defending the trophobionts as well as the host fern from their natural enemies. In addition, a possible three-way mutualistic relationship among the coccids, its host fern and the tending ant is suggested. Differential numbers of coccids on vegetative and fertile leaves is correlated with their phenol content and degree of predation by beetles. Such coloration mimicry by the coccids may enable them to obtain the necessary blend of sorus of the host fern needed to evade beetle detection and attack.


Subject(s)
Coccidia/physiology , Ferns/parasitology , Plant Leaves/parasitology , Animals , Coleoptera/physiology , India , Phenols/analysis , Predatory Behavior
10.
J Plast Reconstr Aesthet Surg ; 61(5): 566-72, 2008.
Article in English | MEDLINE | ID: mdl-17369010

ABSTRACT

OBJECTIVE: Complex wounds of the lower extremity with concomitant Achilles tendon injury can be difficult to reconstruct. We favour the reverse sural artery fasciocutaneous flap because in a single step, flap elevation affords Achilles tendon exposure and adequate soft tissue for reconstruction. It also provides significant time and resource savings for both plastic and orthopaedic surgical teams. MATERIALS AND METHODS: Our case series involved four consecutive patients who presented with Achilles tendon injuries and concomitant complex soft tissue defects. The reverse sural artery flap was planned in conjunction with the orthopaedic service to facilitate their approach for Achilles tendon repair. Outcome was measured as flap survival, time for flap elevation and total operative time. RESULTS: Partial flap loss occurred in one patient. The Achilles repair was performed successfully in all cases. The mean time for flap elevation and Achilles exposure was 43 min (range, 37-52 min). Total operative time was 287 min (range, 211-347 min). CONCLUSION: The reverse sural artery fasciocutaneous flap is a durable, efficient option for simultaneous Achilles tendon reconstruction and wound coverage. Simple flap elevation provides necessary exposure of the Achilles tendon for repair while the flap itself provides ample soft tissue with a reliable blood supply. In our experience, the reverse sural artery fasciocutaneous flap affords a practical method to address two reconstructive challenges in a single procedure.


Subject(s)
Achilles Tendon/injuries , Leg Injuries/surgery , Plastic Surgery Procedures/methods , Surgical Flaps/blood supply , Tendon Injuries/surgery , Accidents, Traffic , Achilles Tendon/surgery , Adult , Child, Preschool , Female , Humans , Male , Microcirculation , Middle Aged , Multiple Trauma/surgery , Soft Tissue Injuries/surgery
11.
Ann Oncol ; 17(1): 97-103, 2006 Jan.
Article in English | MEDLINE | ID: mdl-16282244

ABSTRACT

BACKGROUND: Recombinant human angiostatin (rhAngiostatin) functions as a potent inhibitor of angiogenesis. This study combined rhAngiostatin with a standard chemotherapy regimen in patients with advanced non-small-cell lung cancer (NSCLC). PATIENTS AND METHODS: Eligible patients had chemotherapy-naïve stage IIIB (with pleural effusion) or IV NSCLC, performance status (PS) 0 or 1, no history of bleeding, brain metastasis or requirements for anti-coagulation. Patients received carboplatin (AUC 5) intravenously and paclitaxel (175 mg/m2) intravenously day 1 + subcutaneous rhAngiostatin at either 15 mg or 60 mg twice daily. Cycles were repeated every 3 weeks, for up to six cycles. Patients without progression after completing at least four cycles were continued on maintenance rhAngiostatin until disease progression. RESULTS: Patient characteristics (n = 24) were: 16 males, median age 66 years (range 45-78), 54% PS 1, 83.3% stage IV and 62.5% adenocarcinoma. Grade 3/4 toxicities included: fatigue 47.8%, neutropenia 39.1%, dyspnea 39.1%, vascular 26.1% and infection 17.4%. The overall response rate was 39.1%, 39.1% stable disease and 21.7% progressive disease. Median time to progression was 144 days, and 1-year survival was 45.8%. CONCLUSIONS: rhAngiostatin in combination with paclitaxel and carboplatin is feasible and results in a high disease control rate in patients with advanced NSCLC.


Subject(s)
Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Carcinoma, Non-Small-Cell Lung/drug therapy , Lung Neoplasms/drug therapy , Recombinant Proteins/therapeutic use , Aged , Angiostatins/administration & dosage , Brain Neoplasms/drug therapy , Brain Neoplasms/metabolism , Brain Neoplasms/secondary , Carboplatin/administration & dosage , Carcinoma, Non-Small-Cell Lung/metabolism , Disease Progression , Disease-Free Survival , Feasibility Studies , Female , Humans , Lung Neoplasms/metabolism , Male , Maximum Tolerated Dose , Middle Aged , Neoplasm Staging , Paclitaxel/administration & dosage , Proteomics , Survival Rate , Time Factors
12.
Appl Microbiol Biotechnol ; 71(5): 748-60, 2006 Aug.
Article in English | MEDLINE | ID: mdl-16292532

ABSTRACT

High levels of nitrate are present in groundwater migrating from the former waste disposal ponds at the Y-12 National Security Complex in Oak Ridge, TN. A field-scale denitrifying fluidized bed reactor (FBR) was designed, constructed, and operated with ethanol as an electron donor for the removal of nitrate. After inoculation, biofilms developed on the granular activated carbon particles. Changes in the bacterial community of the FBR were evaluated with clone libraries (n = 500 partial sequences) of the small-subunit rRNA gene for samples taken over a 4-month start-up period. Early phases of start-up operation were characterized by a period of selection, followed by low diversity and predominance by Azoarcus-like sequences. Possible explanations were high pH and nutrient limitations. After amelioration of these conditions, diversification increased rapidly, with the appearance of Dechloromonas, Pseudomonas, and Hydrogenophaga sequences. Changes in NO3, SO4, and pH also likely contributed to shifts in community composition. The detection of sulfate-reducing-bacteria-like sequences closely related to Desulfovibrio and Desulfuromonas in the FBR have important implications for downstream applications at the field site.


Subject(s)
Bacteria/growth & development , Bioreactors , Ecosystem , Water Pollutants, Chemical/metabolism , Bacteria/classification , Bacteria/genetics , Charcoal , Nitrates/metabolism , Phylogeny , Pseudomonas , RNA, Ribosomal, 16S/genetics , Sequence Analysis, DNA , Sulfur-Reducing Bacteria , Uranium , Water Purification/methods
14.
J Appl Microbiol ; 95(2): 390-7, 2003.
Article in English | MEDLINE | ID: mdl-12859773

ABSTRACT

AIMS: To exploit the enterocin regulatory system for regulated expression of genes in Enterococcus. METHODS AND RESULTS: Production of some pediocin-like bacteriocins such as enterocin A in Enterococcus is regulated by a three-component system comprising a histidine kinase (entK ), a response regulator (entR) and an induction factor (entF ). Exposure to the induction factor results in the transcription of gene(s) under the control of the enterocin A promoter, including entA which encodes the bacteriocin. In an effort to exploit this system for expression of genes in Enterococcus, a number of vectors were constructed which contain the entA promoter followed by convenient cloning sites to introduce gene(s) of interest. These vectors were used in an enterococcal background which does not produce induction factor but does produce both the kinase and regulator proteins. The system was tested using the reporter genes ltnI (lacticin 3147 immunity) and gusA (beta-glucuronidase) under the control of the entA promoter. CONCLUSIONS: Upon addition of the induction factor, the beta-glucuronidase activity increased 20-fold when compared with uninduced cells. In addition, concentrations of as little as 0.2 nm synthetic EntF were sufficient to give maximal expression. SIGNIFICANCE AND IMPACT OF THE STUDY: The potential benefit of having an expression system based on EntF is that gene expression can be finely controlled upon addition of low concentrations of a peptide that can easily be artificially synthesized.


Subject(s)
Bacteriocins/biosynthesis , Enterococcus faecium/genetics , Gene Expression Regulation, Bacterial/physiology , Anti-Bacterial Agents/immunology , Bacterial Proteins/immunology , DNA, Bacterial/genetics , Escherichia coli/enzymology , Genes, Bacterial , Genes, Regulator , Genes, Reporter , Genetic Vectors , Glucuronidase/biosynthesis , Plasmids/genetics , Transformation, Genetic
16.
Biol Reprod ; 66(4): 917-23, 2002 Apr.
Article in English | MEDLINE | ID: mdl-11906909

ABSTRACT

Although Smad 3 is known to serve as a signaling intermediate for the transforming growth factor beta (TGFbeta) family in nonreproductive tissues, its role in the ovary is unknown. Thus, we used a recently generated Smad 3-deficient (Smad 3-/-) mouse model to test the hypothesis that Smad 3 alters female fertility and regulates the growth of ovarian follicles from the primordial stage to the antral stage. In addition, we tested whether Smad 3 affects the levels of proteins that control apoptosis, survival, and proliferation in the ovarian follicle. To test this hypothesis, breeding studies were conducted using Smad 3-/- and wild-type mice. In addition, ovaries were collected from Smad 3-/- and wild-type mice on Postnatal Days 2-90. One ovary from each animal was used to estimate the total number of primordial, primary, and antral follicles. The other ovary was used for immunohistochemical analysis of selected members of the B-cell lymphoma/leukemia-2 family of protooncogenes (Bax, Bcl-2, Bcl-x), proliferating cell nuclear antigen (PCNA), and cyclin-dependent kinase 2 (Cdk-2). The results indicate that Smad 3-/- mice have reduced fertility compared with wild type mice. The results also indicate that Smad 3 may not affect the size of the primordial follicle pool at birth, but it may regulate growth of primordial follicles to the antral stage. Further, the results indicate that Smad 3 may regulate the expression of Bax and Bcl-2, but not Bcl-x, Cdk-2, and PCNA. Collectively, these data suggest that Smad 3 may play an important role in the regulation of ovarian follicle growth and female fertility.


Subject(s)
CDC2-CDC28 Kinases , DNA-Binding Proteins/physiology , Ovarian Follicle/growth & development , Trans-Activators/physiology , Animals , Apoptosis , Body Weight , Cell Division , Cell Survival , Cyclin-Dependent Kinase 2 , Cyclin-Dependent Kinases/analysis , DNA-Binding Proteins/deficiency , Female , Fertility , Immunohistochemistry , Male , Mice , Mice, Knockout , Ovarian Follicle/cytology , Ovary/anatomy & histology , Ovary/chemistry , Ovary/physiology , Proliferating Cell Nuclear Antigen/analysis , Protein Serine-Threonine Kinases/analysis , Proto-Oncogene Proteins/analysis , Proto-Oncogene Proteins c-bcl-2/analysis , Smad3 Protein , Trans-Activators/deficiency , bcl-2-Associated X Protein , bcl-X Protein
17.
Am J Bot ; 89(9): 1373-87, 2002 Sep.
Article in English | MEDLINE | ID: mdl-21665739

ABSTRACT

The breeding system and the embryology of Consolea spinosissima, a tree-like opuntioid endemic to Jamaica, were investigated. Morphological and embryological studies revealed that the species is subdioecious, with three sexual morphs present in the 150 × 120 m plot studied at Hellshire Hills, Jamaica. The female morph has pistillate flowers with open stigma lobes, no pollen grains, and sets fruit. The male morph has cryptic staminate flowers with closed stigma lobes, viable pollen grains, and a nonfunctional gynoecium that does not set seed. The weak hermaphrodite morph has low fruit set and "perfect" flowers that superficially resemble the functionally staminate flowers of the male morph. These perfect flowers reach anthesis with viable pollen grains, with no or only a few functional ovules, and with the style supporting pollen tube growth. Embryological studies showed that the critical stage for sex determination occurs earlier in pistillate than in staminate and perfect flowers. Anthers of pistillate flowers abort prior to microspore tetrad formation, whereas ovules of the staminate and perfect flowers degenerate after the complete maturation of the embryo sac. Based on flower structure and embryological data, we hypothesize that the ancestor of C. spinosissima is/was hermaphroditic.

18.
Appl Microbiol Biotechnol ; 56(3-4): 531-8, 2001 Aug.
Article in English | MEDLINE | ID: mdl-11549033

ABSTRACT

We compared carbon flow under constant low-substrate conditions (below 20 microM glucose in situ) in laboratory-scale glucose-fed methanogenic bioreactors containing two very different microbial communities that removed chemical oxygen demand at similar rates. One community contained approximately equal proportions of spiral and cocci morphologies, while the other community was dominated by cocci. In the former bioreactor, over 50% of the cloned SSU rRNA genes and the most common SSU rDNA terminal restriction fragment corresponded to Spirochaetaceae-related sequences, while in the latter bioreactor over 50% of the cloned SSU rRNA genes and the most common SSU rDNA terminal restriction fragment corresponded to Streptococcus-related sequences. Carbon flow was assessed by measuring 14C-labeled metabolites derived from a feeding of [U-14C]glucose that did not alter the concentration of glucose in the bioreactors. Acetate and ethanol were detected in the Spirochaetaceae-dominated reactor, whereas acetate and propionate were detected in the Streptococcus-dominated reactor. A spirochete isolated from a Spirochaetaceae-dominated reactor fermented glucose to acetate, ethanol, and small amounts of lactate. Maximum substrate utilization assays carried out on fluid from the same reactor indicated that acetate and ethanol were rapidly utilized by this community. These data indicate that an acetate- and ethanol-based food chain was present in the Spirochaetaceae-dominated bioreactor, while the typical acetate- and propionate-based food chain was prevalent in the Streptococcus-dominated bioreactor.


Subject(s)
Bioreactors , Carbon/metabolism , Methane/metabolism , Spirochaetaceae/isolation & purification , Streptococcus/isolation & purification , Acetates/metabolism , DNA, Ribosomal/analysis , Ecosystem , Ethanol/metabolism , Fermentation , Glucose/metabolism , Molecular Sequence Data , Polymorphism, Restriction Fragment Length , Propionates/metabolism , RNA, Ribosomal, 16S/genetics , Sequence Analysis, DNA , Spirochaetaceae/classification , Spirochaetaceae/genetics , Spirochaetaceae/metabolism , Streptococcus/classification , Streptococcus/genetics , Streptococcus/metabolism
19.
Anesth Analg ; 93(2): 313-8, 2nd contents page, 2001 Aug.
Article in English | MEDLINE | ID: mdl-11473851

ABSTRACT

UNLABELLED: Faculty clinical time is an extremely valuable commodity. Most departments quantify faculty clinical time on an "availability" basis (e.g., number of days in the operating room or nights on call). We hypothesize that a productivity measure (i.e., determination of actual clinical care delivered rather than availability of such care) would produce different results than the availability system. The "billable hour" was chosen as the measurement device. It was defined as time that anesthesia was actually given, as obtained from the anesthetic record. After collecting data for a year, we found that despite parity using the availability system, the billable hour system detected significant differences between faculty within and between groups. We conclude that "availability" and "productivity" systems produce different conclusions regarding the relative contributions of an individual faculty or subspecialty group. IMPLICATIONS: Accountability of clinical activities by faculty is crucial to the financial status of any department of anesthesia. We hypothesized that methods of availability (e.g., amount of time scheduled for clinical activities) versus productivity measure (actual amount of clinical care delivered) would be quite different between faculty and differing subspecialty groups. Even though the availability system distributed clinical time on an equal basis, there was a wide difference of clinical productivity within and between specialty groups. We conclude that a productivity measure (i.e., billable hours) is a more accurate reflection of faculty productivity than an availability system and is more in line with departmental sources of financial income.


Subject(s)
Anesthesiology , Efficiency , Humans
20.
Proc Natl Acad Sci U S A ; 98(10): 5780-5, 2001 May 08.
Article in English | MEDLINE | ID: mdl-11331753

ABSTRACT

The role of the cardiac myocyte as a mediator of paracrine signaling in the heart has remained unclear. To address this issue, we generated mice with cardiac myocyte-specific deletion of the vascular endothelial growth factor gene, thereby producing a cardiomyocyte-specific knockout of a secreted factor. The hearts of these mice had fewer coronary microvessels, thinned ventricular walls, depressed basal contractile function, induction of hypoxia-responsive genes involved in energy metabolism, and an abnormal response to beta-adrenergic stimulation. These findings establish the critical importance of cardiac myocyte-derived vascular endothelial growth factor in cardiac morphogenesis and determination of heart function. Further, they establish an adult murine model of hypovascular nonnecrotic cardiac contractile dysfunction.


Subject(s)
Endothelial Growth Factors/metabolism , Heart/physiology , Lymphokines/metabolism , Myocardium/metabolism , Animals , Endothelial Growth Factors/genetics , Gene Expression Profiling , Immunohistochemistry , In Situ Hybridization , Lymphokines/genetics , Mice , Mice, Knockout , Models, Animal , Vascular Endothelial Growth Factor A , Vascular Endothelial Growth Factors
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