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PubMed2000

Use of the neisserial lipoprotein (Lip) for subtyping Neisseria gonorrhoeae.

The pathogenic Neisseria species N. meningitidis and N. gonorrhoeae possess an outer membrane lipoprotein, designated Lip, which is present in all strains tested. The predicted protein sequence of Lip consists of a consensus AAEAP amino acid repeat. The objective of this study was to determine the feasibility of using the Lip repeat number and sequence for subtyping of Neisseria gonorrhoeae. The lip genes of each isolate were amplified by PCR and sequenced to determine the repeat number and sequence. Among the 46 strains we examined, eight different Lip repeat numbers were identified, with lengths of 11 (1 strain), 12 (14 strains), 13 (2 strains), 14 (10 strains), 15 (5 strains), 16 (10 strains), 17 (3 strains), and 20 (1 strain) repeats. Analysis indicated differences in the sequences within the repeats that resulted in amino acid alterations in repeat classes that contained multiple strains. Among the 46 isolates examined, we were able to identify 17 unique Lip subtyping patterns.

Amino Acid Sequence↗
PubMed1997

Respiratory morbidity from lymphocytic interstitial pneumonitis (LIP) in vertically acquired HIV infection.

The aim of the study was to define the respiratory morbidity caused by lymphocytic interstitial pneumonitis (LIP) in children with vertically acquired HIV infection. A retrospective case note review was performed on 95 children attending three London hospitals. Clinical and radiological evidence of LIP, acute lower respiratory tract infections, and chronic lung disease was obtained using a structured protocol. A diagnosis of LIP had been made in 33%, and an acute admission due to acute lower respiratory tract infection had occurred in 42% of all children (despite 99% taking regular cotrimoxazole prophylaxis). Admission rates because of acute lower respiratory tract infection were significantly higher in the LIP group (0.38 admissions/child year) than in the non-LIP group (0.17 admissions/child year) (p = 0.0002). Encapsulated bacteria (Streptococcus pneumoniae, Haemophilus influenzae) were most frequently isolated. Improved methods of prevention of acute lower respiratory tract infection may help to reduce the severe respiratory morbidity seen in children with LIP and HIV infection.

Acute Disease↗
PubMed2005

Dynamic circuitry for updating spatial representations. II. Physiological evidence for interhemispheric transfer in area LIP of the split-brain macaque.

With each eye movement, a new image impinges on the retina, yet we do not notice any shift in visual perception. This perceptual stability indicates that the brain must be able to update visual representations to take our eye movements into account. Neurons in the lateral intraparietal area (LIP) update visual representations when the eyes move. The circuitry that supports these updated representations remains unknown, however. In this experiment, we asked whether the forebrain commissures are necessary for updating in area LIP when stimulus representations must be updated from one visual hemifield to the other. We addressed this question by recording from LIP neurons in split-brain monkeys during two conditions: stimulus traces were updated either across or within hemifields. Our expectation was that across-hemifield updating activity in LIP would be reduced or abolished after transection of the forebrain commissures. Our principal finding is that LIP neurons can update stimulus traces from one hemifield to the other even in the absence of the forebrain commissures. This finding provides the first evidence that representations in parietal cortex can be updated without the use of direct cortico-cortical links. The second main finding is that updating activity in LIP is modified in the split-brain monkey: across-hemifield signals are reduced in magnitude and delayed in onset compared with within-hemifield signals, which indicates that the pathways for across-hemifield updating are less effective in the absence of the forebrain commissures. Together these findings reveal a dynamic circuit that contributes to updating spatial representations.

Animals↗
PubMed1996

Spatially tuned auditory responses in area LIP of macaques performing delayed memory saccades to acoustic targets.

1. The lateral intraparietal area (area LIP) of the macaque's posterior parietal cortex (PPC) lies in the dorsal stream of extrastriate visual areas. It receives extensive visual inputs and sends outputs to several eye movement centers. It contains neurons with visual and saccade-related responses suggesting a role of area LIP in programming saccadic eye movements to visual targets. Because primates can also orient to nonvisual stimuli, we investigated whether LIP neurons process stimuli of other modalities besides the visual one by comparing their activity in auditory and visual saccade tasks. 2. We recorded the activity of single neurons of Macaca mulatta monkeys while they performed memory saccades to acoustic and visual targets. We analyzed the activity during stimulus presentation (stimulus period, S) and during the delay (memory period, M) between stimulus presentation and the saccade to its remembered location. 3. Among 80 area LIP neurons tested, we found 44 that had S period and/or M period responses following presentation of the auditory stimulus. Most of these responses were spatially tuned, i.e., selective for the left or right stimulus location (27 of 29 S responses; 25 of 29 M responses). 4. The majority of neurons with responses in the auditory memory saccade task also responded in the visual version of the task. Eighty-nine percent (24/27) were clearly bimodal in the S period, and 88% (23/26) were bimodal in the M period. 5. Almost all the neurons with spatially tuned auditory responses that were bimodal were also spatially tuned in their visual responses (20/22 for S responses; 18/19 for M responses). The spatial tuning for the two modalities was the same in 85% (17/20) of the tested neurons for the S responses, and in 83% (15/18) of the tested neurons for the M responses. 6. Area LIP contains a population of neurons that respond to both visual and auditory stimuli. This result is consistent with our finding that the memory activity of many LIP cells encodes the next planned saccade. If cells are coding planned movements, they should be active independently of the sensory modality of the target for the movement, as was the case for most of the neurons described in the present study.

Acoustic Stimulation↗
PubMed2001

Neural basis of a perceptual decision in the parietal cortex (area LIP) of the rhesus monkey.

We recorded the activity of single neurons in the posterior parietal cortex (area LIP) of two rhesus monkeys while they discriminated the direction of motion in random-dot visual stimuli. The visual task was similar to a motion discrimination task that has been used in previous investigations of motion-sensitive regions of the extrastriate cortex. The monkeys were trained to decide whether the direction of motion was toward one of two choice targets that appeared on either side of the random-dot stimulus. At the end of the trial, the monkeys reported their direction judgment by making an eye movement to the appropriate target. We studied neurons in LIP that exhibited spatially selective persistent activity during delayed saccadic eye movement tasks. These neurons are thought to carry high-level signals appropriate for identifying salient visual targets and for guiding saccadic eye movements. We arranged the motion discrimination task so that one of the choice targets was in the LIP neuron's response field (RF) while the other target was positioned well away from the RF. During motion viewing, neurons in LIP altered their firing rate in a manner that predicted the saccadic eye movement that the monkey would make at the end of the trial. The activity thus predicted the monkey's judgment of motion direction. This predictive activity began early in the motion-viewing period and became increasingly reliable as the monkey viewed the random-dot motion. The neural activity predicted the monkey's direction judgment on both easy and difficult trials (strong and weak motion), whether or not the judgment was correct. In addition, the timing and magnitude of the response was affected by the strength of the motion signal in the stimulus. When the direction of motion was toward the RF, stronger motion led to larger neural responses earlier in the motion-viewing period. When motion was away from the RF, stronger motion led to greater suppression of ongoing activity. Thus the activity of single neurons in area LIP reflects both the direction of an impending gaze shift and the quality of the sensory information that instructs such a response. The time course of the neural response suggests that LIP accumulates sensory signals relevant to the selection of a target for an eye movement.

Action Potentials↗
PubMed1990

The role of the dorsal lip in the induction of heart mesoderm in Xenopus laevis.

We have examined the tissue interactions responsible for the expression of heart-forming potency during gastrulation. By comparing the specification of different regions of the marginal zone, we show that heart-forming potency is expressed only in explants containing both the dorsal lip of the blastopore and deep mesoderm between 30 degrees and 45 degrees lateral to the dorsal midline. Embryos from which both of these 30 degrees-45 degrees dorsolateral regions have been removed undergo heart formation in two thirds of cases, as long as the dorsal lip is left intact. If the dorsal lip is removed along with the 30 degrees-45 degrees regions, heart formation does not occur. These results indicate that the dorsolateral deep mesoderm must interact with the dorsal lip in order to express heart-forming potency. Transplantation of the dorsal lip into the ventral marginal zone of host embryos results in the formation of a secondary axis; in over half of cases, this secondary axis includes a heart derived from the host mesoderm. These findings suggest that the establishment of heart mesoderm is initiated by a dorsalizing signal from the dorsal lip of the blastopore.

Animals↗
PubMed2002

Laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS): comparison of different internal standardization methods using laser-induced plasma (LIP) emission and LA-ICP-MS signals.

The source of signal variations that governs the analytical performance of laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) was investigated in this study. In order to specify the source of signal variations of LA-ICP-MS, laser-induced plasma (LIP) Fe emission, LA-ICP-MS Fe+ and LA-ICP-MS Ni+ signals were used as internal standards for the determination of trace elements in low-alloy steel certified reference materials (BS 50D and JSS 1005-1008). Fe 1373.5 nm emission signals from LIP were measured, while trace element LA-ICP-MS signals were collected. After that, the LIP emission signals, LA-ICP-MS Fe+ and LA-ICP-MS Ni+ signals were used as internal standards, and the analytical performance was evaluated by the RSDs and the correlation coefficients (r) of the calibration curves. The improvement factors were dependent on the internal standardization methods. Analytical precisions (RSDs) of trace element LA-ICP-MS signals were improved by factors of 1.5-3.3 using LIP Fe emission signals as an internal standard. The improvement factors of 2.5 - 5.9 and 4.1 - 17 were obtained by using LA-ICP-MS Fe+ and LA-ICP-MS Ni+ signals as internal standards, respectively. Better correlation coefficients (r) were also obtained using the LA-ICP-MS signal compensation (0.9985 by LA-ICP-MS Fe+ and 0.9996 by LA-ICP-MS Ni+) rather than the LIP Fe emission compensation (0.9932). In this paper we compare and discuss the analytical performance achieved by LA-ICP-MS using LIP Fe emission, LA-ICP-MS Fe+ and LA-ICP-MS Ni+ signals as internal standards.

Journal Article↗
PubMed2000

[The design, functions and clinic applications of lip bumper].

OBJECTIVE: This paper introduced the principle of design, methods of fabrication, indications and functions of lip bumper, and advocated the application of lip bumper in orthodontic clinic. METHODS: Two typical cases treated with lip bumper were introduced. Some notices and experiences of applying lip bumpers were summed up. RESULTS: There were following functions of lip bumper: as a space maintainer, Fränkel effect, headgear effect, post-maxillary expansion retention, derotation of molars, and combined using with headgear. CONCLUSION: The advantages of lip bumper are inclusions of a wide range of indication, wearing for 24 hours per day, easily fabricating and prefabricating, comfortable and hidden for patients.

Child↗
PubMedDate not supplied

[Bite jumping appliance with lower lip bumper].

The removable bite jumping appliance with lower lip bumper is a new orthodontic appliance designed to correct the abnormal habit of lower lip biting children with mentalis muscle hyperactivity. Upper anterior teeth protrusion, mandible retrusion, lower anterior teeth lingual collapse and anterior deep bite usually are found in association with this lower lip biting habit, especially in the mixed dentition period (7-12 yrs). The function of this appliance is similar to the partial functional appliance. It is made into two parts: upper removable plate with anterior inclined bite plane and lower lip bumper attached to the upper plate. Three cases are discussed and compared before and after treatment. Changes in both skeletal and dental pattern were recorded in the following aspects: increase in the posterior rotation of mandible (increased SN-MP), stimulation of forward growth of the mandible (the increase is SNB value overcomes the increase in SNA, through reduction ANB), retroclination of upper maxillary teeth (reduced 1-NA), proclination of lower anterior teeth (increased 1-NB), the reduction of overjet. Additionally, the normal position of the lower lip provided by this appliance effectively corrects the lip biting with mentalis muscle hyperactivity.

Activator Appliances↗
PubMed2006

Development of the upper lip: morphogenetic and molecular mechanisms.

The vertebrate upper lip forms from initially freely projecting maxillary, medial nasal, and lateral nasal prominences at the rostral and lateral boundaries of the primitive oral cavity. These facial prominences arise during early embryogenesis from ventrally migrating neural crest cells in combination with the head ectoderm and mesoderm and undergo directed growth and expansion around the nasal pits to actively fuse with each other. Initial fusion is between lateral and medial nasal processes and is followed by fusion between maxillary and medial nasal processes. Fusion between these prominences involves active epithelial filopodial and adhering interactions as well as programmed cell death. Slight defects in growth and patterning of the facial mesenchyme or epithelial fusion result in cleft lip with or without cleft palate, the most common and disfiguring craniofacial birth defect. Recent studies of craniofacial development in animal models have identified components of several major signaling pathways, including Bmp, Fgf, Shh, and Wnt signaling, that are critical for proper midfacial morphogenesis and/or lip fusion. There is also accumulating evidence that these signaling pathways cross-regulate genetically as well as crosstalk intracellularly to control cell proliferation and tissue patterning. This review will summarize the current understanding of the basic morphogenetic processes and molecular mechanisms underlying upper lip development and discuss the complex interactions of the various signaling pathways and challenges for understanding cleft lip pathogenesis.

Animals↗
PubMedDate not supplied

Reconstruction of small- and medium-sized defects of the lower lip.

Defects of up to one third of the lower lip can usually be closed primarily, using one of the excision shapes described above. Defects of 30% to 50% of the lower lip can be closed with a stair-step or lip-switch flap. In most circumstances, stair-step reconstruction attains good function more quickly than the lip switch flap and has a better aesthetic result. Defects of 50% to 75% of the lower lip can be closed with a fan flap or a Karapandzic flap; the Karapandzic flap generally provides a better functional result. Both of these flaps cause rounding of the corner of the mouth that compromise the aesthetic result.

Age Factors↗
PubMedDate not supplied

A familial occurrence of lip anomaly.

Lip pits are among the rarest congenital deformities recorded. Initially reported in 1845, its familial occurrence has been reported just once. These developmental anomalies occur either as an isolated defect or in association with other developmental deformities, including cleft lip, cleft palate, or both. They may be located at the commissures of the lips or at the midline of the lower lip. Lip pits are often inherited as an autosomal dominant trait with variable penetrance. Our report of a family in which all of the 3 children (2 girls and 1 boy) and their father were involved is in concert with the latter statement.

Adolescent↗
PubMed2005

Craniofacial development in children with unilateral cleft lip and palate.

Unilateral cleft lip and palate is the most common cleft in humans. We investigated the craniofacial morphology of Turkish children with unilateral complete cleft lip and palate who had operations to close the cleft lip when they were 3 months old and to close the palate at 12 months. They were not given orthopaedic or orthodontic treatment. We compared 42 patients with unilateral complete cleft lip and palate (UCCLP) with 45 control children without UCCLP at mean ages of 13 and 15 years. The children with UCCLP had considerable morphological deviations compared with the matched children without clefts. They had significantly shorter and more posteriorly positioned maxillas (p<0.01). There was also an increase in cranial base angle (p<0.05), mandibular plane and gonial angle (p<0.01). There was a reduction in the posterior facial height (p<0.05) and an increase in the anterior facial height (p<0.01). The profile of the soft tissue was more convex (p<0.001) and the upper lip was thinner than in the children in the control group (p<0.01), and their noses were relatively further backwards and downwards (p<0.01).

Adolescent↗
PubMed2004

Secondary reconstruction of asymmetric volume deficits of the lips: a transverse twist flap technique.

The reconstructive surgeon, dealing with both congenital anomalies such as clefts, and post-surgical or post-traumatic defects, may, on occasion be faced with a situation where there is either a unilateral deficit or excess of lip volume, or an asymmetry with bilateral volume inequalities. The classic examples of this are the characteristic whistle notch deformities sometimes seen after cleft-lip repairs. This paper presents another useful solution to such problems. The method involves the transposition of a transversely-oriented flap of mucosa, elevated on a connective tissue/muscle pedicle, and twisted or rotated 180 degrees from the contralateral side of the lip, to help fill the defect. The flap is asymmetrical, thus enabling transposition of more tissue into the primary defect than is lost from the donor site. The principal advantage is that in a lip in which there is already an overall paucity of tissue, nothing further is discarded, while at the same time, tissue is replaced where it is most needed. A secondary benefit is that with proper design, the lip can be shortened from side to side and therefore filled out in the antero-posterior dimension. Technical details of the method are explained and the versatility of the technique is illustrated.

Adolescent↗
PubMed2006

Lip defects due to tumor excision: apropos of 899 cases.

Reconstructive surgery of the lips after resection of tumors requires a complete understanding of the anatomy of this region. Most lip cancers remain localized and grow slowly, with a propensity for superficial rather than vertical spread. From January 1983 to December of 2005, 899 patients underwent reconstructive surgery for skin tumors involving the lips. SCCs were the most frequent skin tumors on male patients whereas BCCs were most common on the female patients. The lower lip was the anatomic zone most frequently involved in our series. Preoperative evaluation of the patients was performed in all cases. In the last five-years, we have performed preoperative fine needle aspiration (FNA) biopsy of the tumor. The FNA sample was then examined by ThinPrep technique (Cytolyt; Cytyc, Co, Boxborough, MA, USA). In our series, from the 550 patients who had a five-year follow-up we observed 62 recurrences of the primary tumor. The five-year recurrence rate was 11.28%. The aim of this retrospective study is to report our experience in the treatment of lips tumors with selective combination of treatment modalities.

Adult↗
PubMed2006

Denervated or innervated flaps for the lower lip reconstruction? Are they really different to get a good result?

OBJECTIVE: This study compares innervated and denervated flaps for the lower lip reconstruction in terms of oral sphincter function and sensation. STUDY DESIGN AND SETTING: A prospective trial. METHODS: This study was carried out on 31 patients with lower lip carcinoma. They were divided in 2 groups: 18 patients with denervated local flaps and 13 patients with innervated flaps. During the follow-up period, all patients were evaluated by electromyography tests and an assessment of the sensation on the lower lip and sphincter function was undertaken by clinical parameters. RESULTS: Compound muscle action potential (CMAP) was obtained in all patients. The amplitudes of CMAP were below normal and the values for distal motor latency (DML) were slightly longer than normal values. Interference patterns were observed on whistling in all cases. There were no differences in terms of sphincteric function in each group. CONCLUSIONS: The denervated random local flaps used for the lower lip reconstruction have no functional inferiority when compared to the innervated-pedicled local flaps. SIGNIFICANCE: This study demonstrates that denervated flaps can be employed for a functional lip reconstruction. EBM RATING: B-2b.

Adult↗
PubMed1979

Primary reconstruction of defects in the upper and lower lips following tumor excision.

Three cases of basal cell carcinoma and epithelioma in the upper and lower lips are reported. The defects in the upper lip following tumor excision were repaired with an application of Burow's technique. Martin's method, after modification of Bernard cheiloplasty, was used for the repair of the lower lip defect. The methods proved to be quite effective in providing excellent aesthetic results. No disturbance was noted in the activity of the repaired upper lips. The labial function, however, associated with the orbicularis oris was left impaired in the newly formed lower lip.

Adult↗
PubMed1979

The arrangement of muscle fibres in cleft lips.

A total of 63 laterally situated partial clefts of the lip were studied. The biopsies obtained during the first operation were evaluated histologically. With a special stain, the fibre of the orbicularis oris muscle were demonstrated and their arrangement in relation to the cleft lip was recorded. The results indicate a close relationship between type and degree of the cleft and the arrangement of the muscle bundles: In microforms like lip indentations and minor clefts of the lip the natural anatomy is almost unaltered. The muscle "flows" around the "obstacle". But the larger the cleft the more often the muscle fibres end right at the border of the cleft and insertions are often found here. In the remaining skin bridge the number of muscle fibres decreases and their arrangement deteriorates. In the extreme forms, i.e. the band of Simonart and the completely cleft lip, we must assume that most of the fibres stop at the border of the cleft as muscle no longer crosses the defect.

Cleft Lip↗