The Reproductive Biology of Two Species of Diplusodon Pohl (Lythraceae) from Serra do Cipó, Southeastern Brazil

Abstract: The reproductive biology of two shrub species of Diplusodon (Lythraceae), D. hirsutus and D. orbicularis, was studied. Their distribution is restricted, mainly associated with "campos rupestres", a montane biome in SE Brazil. Both species proved to be self-compatible but because of herkogamy they are greatly dependent on visitors to effect pollination. The main pollinators are medium-sized bees. In experiments where pollinators were excluded or discouraged the percentage of abscised fruits was total or extremely high; most of these fruits dropped within the first two weeks after pollination in D. orbicularis and three weeks in D. hirsutus. The percentage of surviving fruits from control or manual pollination was higher in D. orbicularis ( ca. 70 %) than in D. hirsutus ( ca. 50 %). Seed set was very variable, with slightly lower means in D. hirsutus. Within each species the mean seed set was similar in self-, cross-pollinated fruits, and controls. In both species, the similarity between control and manual pollination fruit survival curves suggests that factors other than pollen limitation are the cause of abortion in the study area. The high rate of abscission, which was also observed in unmanipulated fruits, was attributed to resource limitation. In D. hirsutus this was caused by drought during seed development. In D. orbicularis it was enhanced by nutrient drain by shoot-galling flies. The lack of selective abortion of either selfed fruits or fruits with a small number of seeds may be a useful mechanism to overcome this detrimental effect which is felt later during fruit development.     

Environmental transmission of a sulfur-oxidizing bacterial gill endosymbiont in the tropical lucinid bivalve Codakia orbicularis.

Codakia orbicularis is a large tropical member of the bivalve mollusk family Lucinidae which inhabits shallow-water sea-grass beds (Thalassia testudinum environment) and harbors sulfur-oxidixing endosymbiotic bacteria within bacteriocytes of its gill filaments. When a C. orbicularis-specific 16S rDNA (DNA encoding rRNA) primer is used with a bacterium-specific 16S rDNA reverse primer in amplifications by PCR, the primer set was unsuccessful in amplifying symbiont DNA targets from ovaries, eggs, veligers, and metamorphosed juveniles (600 microns to 1 mm in shell length) cultivated in sterile sand, whereas successful amplifications were obtained from gill tissue of adult specimens and from metamorphosed juveniles (600 microns to 1 mm in shell length) cultivated in unsterilized sea-grass bed sand. To ascertain the presence of the symbiont target in juveniles, restriction fragment length polymorphism analysis, Southern blotting, and transmission electron microscopy were used. Specific hybridizations and observation of endosymbiotic bacteria in the gills of numerous juveniles cultivated in unsterilized sea-grass bed sand showed that the sulfur-oxidizing endosymbionts of C. orbicularis are environmentally transmitted to the new generation after larval metamorphosis.     

The resection of orbicularis oculi muscle from the upper eyelid in experimental surgery on the monkey

The purpose of this study was to determine the maximum amount of orbicularis oculi muscle that may safely be resected from the upper eyelid without causing functional abnormalities. Measured amounts of that muscle were surgically excised from both upper eyelids in six cynomolgus monkeys. All the eyelids were photographed and videotaped at progressively increased intervals to permit the evaluation of wound healing, scarring, and function. Our preliminary results revealed that the excision of preseptal and partial supraorbital orbicularis oculi muscle, preseptal and complete supraorbital muscle, or pretarsal muscle only did not result in lagophthalmos. Complete resection of pretarsal, preseptal, and supraorbital orbicularis oculi did result in lagophthalmos but caused no corneal injury. The orbicularis oculi muscle in the cynomolgus monkey is similar to that in humans, but it is not yet clear whether our findings in the monkey are applicable in humans. A determination of the maximum amount of orbicularis oculi muscle that can safely be excised in humans would enable plastic surgeons to better understand and develop techniques for eyelid reconstruction and blepharoplasty.     

Development of the orbicularis oris muscle in normal and cleft lip and palate human fetuses using three-dimensional computer reconstruction

As part of an ongoing study of cleft lip and palate fetal morphology, normal and dysmorphic development of the human fetal orbicularis oris muscle was studied in a cross-sectional sample of 29 human fetuses (20 "normal" and 9 cleft lip and palate) ranging in age from 8 to 21 postmenstrual weeks. The specimens were embedded in celloidin and sectioned at 20 microns, and every tenth section was stained with hematoxylin and eosin. A computer reconstruction technique was applied to produce three-dimensional representations of the orbicularis oris muscle. The orbicularis oris muscle in the normal fetal sample with discernible lip fibers (N = 15) increased symmetrically in both fiber density and complexity from 12 to 21 weeks. Metrically, muscle volume and thickness growth curves were consistent with qualitative observations. In contrast, the unilateral cleft lip and palate fetal specimens with discernible lip fibers (N = 3) exhibited a 3.5-week delay in overall muscle development, asymmetrical fiber distribution, and abnormal fiber insertions. However, quantitatively, no significant (p greater than 0.05) differences were noted in orbicularis oris muscle thickness or volume between the normal and cleft lip and palate fetal specimens through 21 weeks. Findings suggest that orbicularis muscle deficiency, noted clinically in cleft lip and palate neonates, may be a result of perinatal functional dysmorphogenesis rather than congenital mesenchymal reduction or deficiency.     

Repositioning the orbicularis oculi muscle in the composite rhytidectomy.

While blepharoplasties are routinely done with face lift procedures, the improvement is accomplished by removing excess orbital fat with eyelid skin and muscle along the incisional line. The orbicularis oculi muscle remains intact as its inferior border, which has become ptotic and redundant with aging, and actually remains in the same position following a conventional lower lid blepharoplasty and rhytidectomy. However, by elevating the orbicularis oculi with the cheek fat and platysma in a composite face lift flap, and by excising the redundant inferior border of the orbicularis muscle, a total rejuvenation of the malar area is accomplished. The descent of the orbicularis oculi muscle is in an inferolateral vector, whereas the vector of facial aging is inferomedial. Thus, repositioning the orbicularis oculi is in a superomedial vector and is obligatory in a composite rhytidectomy.     

烟碱型乙酰胆碱受体在面神经支配的口轮匝肌和躯体神经支配的腓肠肌中的表达差异研究

目的:研究烟碱型乙酰胆碱受体在在面神经支配的口轮匝肌和躯体神经支配的腓肠肌运动终板处的表达差异及可能的原因。方法:分离SD大鼠的口轮匝肌和腓肠肌,通过免疫共沉淀技术计算口轮匝肌和腓肠肌肌肉特异性激酶(Muscle Specific Kinase,MuSK)的表达以及MuSK磷酸化水平。对MuSK的上游信号通路中能使其发生磷酸化的集聚蛋白Agrin、低密度脂蛋白受体相关蛋白4(low-density lipoprotein receptor-related protein 4,Lrp4)以及表皮生长因子家族受体ErbB2、ErbB3和ErbB4(epidermal growth factor receptor)免疫荧光染色,计算这两条不同通路中的蛋白在运动终板处的表达水平。结果:口轮匝肌中MuSK磷酸化水平显著高于腓肠肌(P<0.05)。口轮匝肌与腓肠肌的运动终板处的Agrin和Lrp4表达没有显著差异(P>0.05)。口轮匝肌ErbB2、ErbB3、ErbB4的表达显著高于其在腓肠肌运动终板处的表达(P<0.01)。结论:口轮匝肌和腓肠肌运动终板ErbB、ErbB3、ErbB4的差异表达造成MuSK磷酸化水平不同,可能是两种肌肉运动终板处烟碱型乙酰胆碱亚基表达量不同的原因。     

Partial lip resection with orbicularis oris transposition for lower lip correction in unilateral facial paralysis.

Malfunction of the marginal mandibular nerve, either in combination with a generalized facial palsy or in isolation, can cause an unpleasant and disturbing appearance around the mouth. In total palsy, a cross-facial nerve graft combined with a free vascularized muscle transplant will usually deal with this problem successfully; however, all older procedures used in this situation are unpredictable. For the isolated palsy, procedures such as digastric muscle transfer or sling suspension are not uniformly successful. A method using the contralateral, nonaffected lower lip orbicularis muscle is described. A wedge is removed from the paralyzed lower lip and the orbicularis is advanced to the modiolus to provide a functional orbicularis all the way across the lower lip up to the angle of the mouth. This is a simple outpatient procedure that has produced satisfactory results in most cases.     

Intraoperative injection of botulinum toxin A into orbicularis oculi muscle for the treatment of crow's feet

The purpose of this investigation was to evaluate the degree of efficacy of eliminating crow's feet by means of direct injection of botulinum toxin A into orbicularis oculi muscles under direct surgical vision during either blepharoplasty or face lift operations. Eighteen patients were injected with Botox A-14 in each orbicularis oculi muscle. Dilution was obtained by adding 4 ml of preservative-free saline to 100 IU of Botox A. Doses ranged from 15 to 50 IU in each muscle, varying according to the severity of wrinkles and intensity of muscle contraction. In 10 patients (56 percent), the Botox was injected throughout the outer surface of both orbicularis oculi dissected during a face-lift operation. In eight other patients (44 percent), the toxin was injected into the inner surface of both orbicularis oculi exposed during classic blepharoplasty procedures. Most authors have demonstrated that the effect produced by transcutaneous Botox lasts between 4 and 6 months; the paralysis obtained by direct muscular injection was effective for 9 months in 14 patients (78 percent) and 10 months in the other 4 patients (22 percent). Results were documented by means of preinjection and postinjection photographs, videotapes, and electromyographs. Neither local nor general adverse effects were noted. The improvement obtained in crow's feet was satisfactory to the patient and to us. The use of Botox intraoperatively permitted at the same time not only the treatment of crow's feet by paralysis of orbicularis oculi muscles but also the correction of senile changes in the lids and face by means of either blepharoplasty or face-lift operations.     

Festoons of orbicularis muscle as a cause of baggy eyelids

Occasionally, baggy eyelids are caused by a laxity of the orbicularis oculi muscle. The extent of these orbicularis festoons is evaluated by a careful examination--including the "squinch" and the "pinch" tests. We excise such festoons of excess muscle and then support the orbicularis oculi of the lower lid by using periosteal and muscular sutures. (Orbicularis plication is an alternate procedure for the lower lid). Any muscle festoons of the upper lid are simply excised.     

Detection of the free-living forms of sulfide-oxidizing gill endosymbionts in the lucinid habitat (Thalassia testudinum environment)

Target DNA from the uncultivable Codakia orbicularis endosymbiont was PCR amplified from sea-grass sediment. To confirm that such amplifications originated from intact bacterial cells rather than free DNA, whole-cell hybridization (fluorescence in situ hybridization technique) with the specific probe Symco2 was performed along with experimental infection of aposymbiotic juveniles placed in contact with the same sediment. Taken together, the data demonstrate that the sulfide-oxidizing gill endosymbiont of Codakia orbicularis is present in the environment as a free-living uncultivable form.     

Phylomark, a tool to identify conserved phylogenetic markers from whole-genome alignments

The sequencing and analysis of multiple housekeeping genes has been routinely used to phylogenetically compare closely related bacterial isolates. Recent studies using whole-genome alignment (WGA) and phylogenetics from >100 Escherichia coli genomes has demonstrated that tree topologies from WGA and multilocus sequence typing (MLST) markers differ significantly. A nonrepresentative phylogeny can lead to incorrect conclusions regarding important evolutionary relationships. In this study, the Phylomark algorithm was developed to identify a minimal number of useful phylogenetic markers that recapitulate the WGA phylogeny. To test the algorithm, we used a set of diverse draft and complete E. coli genomes. The algorithm identified more than 100,000 potential markers of different fragment lengths (500 to 900 nucleotides). Three molecular markers were ultimately chosen to determine the phylogeny based on a low Robinson-Foulds (RF) distance compared to the WGA phylogeny. A phylogenetic analysis demonstrated that a more representative phylogeny was inferred for a concatenation of these markers compared to all other MLST schemes for E. coli. As a functional test of the algorithm, the three markers (genomic guided E. coli markers, or GIG-EM) were amplified and sequenced from a set of environmental E. coli strains (ECOR collection) and informatically extracted from a set of 78 diarrheagenic E. coli strains (DECA collection). In the instances of the 40-genome test set and the DECA collection, the GIG-EM system outperformed other E. coli MLST systems in terms of recapitulating the WGA phylogeny. This algorithm can be employed to determine the minimal marker set for any organism that has sufficient genome sequencing.     

Antimutagenic mechanisms of Phyllanthus orbicularis when hydrogen peroxide is tested using Salmonella assay

Phyllanthus orbicularis is a medicinal plant, endemic to Cuba, whose aqueous extract has proven antiviral properties and antimutagenic activities against aromatic amines and hydrogen peroxide. In addition, this plant extract presents antioxidant activity. In this paper, using the Salmonella assay with the experimental approaches of co-incubation, pre- and post-treatments, it is shown that the P. orbicularis extract protects bacterial cells from oxidative damage and mutation by some intracellular mechanism, irrespective of its antioxidant activity.     

Composite rhytidectomy.

Signs of aging in the face reflect the change in position of deep anatomic elements, which are the platysma muscle, cheek fat, and the orbicularis oculi muscle. These changes occur from progressive ptosis of these elements, which continue to keep their intimate relationship with each other throughout the aging process. Conventional face lift procedures disrupt this normal relationship by separating the skin from these elements. All SMAS techniques reposition only the platysma muscle without repositioning the cheek fat and orbicularis muscle. This composite rhytidectomy allows elevation of a composite musculocutaneous flap containing all three elements for repositioning while maintaining their intimate relationship with each other and with the skin. One-hundred and sixty-seven composite rhytidectomies have been done with impressive results and minimal complications.     

Variable number of tandem repeat markers in the genome sequence of Mycosphaerella fijiensis, the causal agent of black leaf streak disease of banana (Musa spp)

We searched the genome of Mycosphaerella fijiensis for molecular markers that would allow population genetics analysis of this plant pathogen. M. fijiensis, the causal agent of banana leaf streak disease, also known as black Sigatoka, is the most devastating pathogen attacking bananas (Musa spp). Recently, the entire genome sequence of M. fijiensis became available. We screened this database for VNTR markers. Forty-two primer pairs were selected for validation, based on repeat type and length and the number of repeat units. Five VNTR markers showing multiple alleles were validated with a reference set of isolates from different parts of the world and a population from a banana plantation in Costa Rica. Polymorphism information content values varied from 0.6414 to 0.7544 for the reference set and from 0.0400 and 0.7373 for the population set. Eighty percent of the polymorphism information content values were above 0.60, indicating that the markers are highly informative. These markers allowed robust scoring of agarose gels and proved to be useful for variability and population genetics studies. In conclusion, the strategy we developed to identify and validate VNTR markers is an efficient means to incorporate markers that can be used for fungicide resistance management and to develop breeding strategies to control banana black leaf streak disease. This is the first report of VNTR-minisatellites from the M. fijiensis genome sequence.     

Laser blepharoplasty with transconjunctival orbicularis muscle/septum tightening and periocular skin resurfacing: a safe and advantageous technique

Carbon dioxide (CO2) laser blepharoplasty with orbicularis oculi muscle tightening and periorbital skin resurfacing is a safe procedure that produces excellent aesthetic results and diminishes the occurrence of complications associated with skin and muscle resection in the lower lid, particularly permanent scleral show and ectropion. The authors present a review of 196 cases of carbon dioxide laser blepharoplasty and periocular laser skin resurfacing performed at their center from April of 1994 to September of 1998. Of these cases, 113 patients underwent four-lid blepharoplasty, 59 underwent upper lid blepharoplasty only, and 24 underwent lower lid blepharoplasty only. Prophylactic lateral canthopexy was performed in 24 patients. Concomitant procedures (brow lift/rhytidectomy/rhinoplasty) were performed in 92 patients. The carbon dioxide laser blepharoplasty procedure resulted in no injuries to the globe, cornea, or eyelashes. Combined with laser tightening of the orbicularis oculi muscle and septum and periocular skin resurfacing, the transconjunctival approach to lower blepharoplasty preserves lower lid skin and muscle. Elimination of the traditional scalpel skin/muscle flap procedure results in a dramatically lower complication rate, particularly with regard to permanent ectropion and scleral show. Laser shrinkage of the orbicularis muscle and septum through the transconjunctival incision enables the correction of muscle aging changes such as orbicularis hypertrophy and malar festoons. The addition of periocular resurfacing enables the correction of skin aging changes of the eyelid that are not addressed by traditional scalpel blepharoplasty. In addition, lateral canthopexy constitutes an important adjunct to the laser blepharoplasty procedure for the correction of lower lid canthal laxity.     

A set of 37 microsatellite DNA markers for genetic diversity and structure analysis of Atlantic salmon Salmo salar populations

Atlantic salmon Salmo salar microsatellite markers from a large database were analysed and selected with technical, economic and genetic criteria to provide an optimized set of polymorphic DNA markers for the analysis of the genetic diversity and the structure of anadromous Atlantic salmon populations. A set of 37 microsatellite markers was identified that are easy to use and provide a high level of differentiation power.     

Construction of a genetic linkage map in tetraploid species using molecular markers

This article presents methodology for the construction of a linkage map in an autotetraploid species, using either codominant or dominant molecular markers scored on two parents and their full-sib progeny. The steps of the analysis are as follows: identification of parental genotypes from the parental and offspring phenotypes; testing for independent segregation of markers; partition of markers into linkage groups using cluster analysis; maximum-likelihood estimation of the phase, recombination frequency, and LOD score for all pairs of markers in the same linkage group using the EM algorithm; ordering the markers and estimating distances between them; and reconstructing their linkage phases. The information from different marker configurations about the recombination frequency is examined and found to vary considerably, depending on the number of different alleles, the number of alleles shared by the parents, and the phase of the markers. The methods are applied to a simulated data set and to a small set of SSR and AFLP markers scored in a full-sib population of tetraploid potato.     

Assessing the power of informative subsets of loci for population assignment: standard methods are upwardly biased

It is well known that statistical classification procedures should be assessed using data that are separate from those used to train the classifier. This principle is commonly overlooked when the classification procedure in question is population assignment using a set of genetic markers that were chosen specifically on the basis of their allele frequencies from amongst a larger number of candidate markers. This oversight leads to a systematic upward bias in the predicted accuracy of the chosen set of markers for population assignment. Three widely used software programs for selecting markers informative for population assignment suffer from this bias. The extent of this bias is documented through a small set of simulations. The relative effect of the bias is largest when screening many candidate loci from poorly differentiated populations. Simple unbiased methods are presented and their use encouraged.