Phospholipase D (PLD) is present in Leishmania donovani and its activity increases in response to acute osmotic stress

We report here that the signaling molecule phospholipase D (PLD) is present in the parasitic protozoan Leishmania donovani. In vitro enzymatic activity is dependent on Ca2+ and Mg2+ ions, its basal activity is stimulated by phosphatidyl-inositol-4,5-bisphosphate (PIP2) and its pH optima are pH 8.0 and pH 6.0. PLD activity increases 3-fold about 5 min after an abrupt decrease in osmolality from 317 mOsm (isosmotic) to 155 mOsm and increases 1.5-fold in response to an abrupt increase in osmolality to 617 mOsM. Cells grown for > 24 h under the anisosmotic conditions showed only marginal changes in activity compared to the controls grown under isosmotic conditions, indicating an adaptation to long-term exposure to hypo- or hyper-osmolarity. Immunologically, two isoforms, PLD1 and PLD2, are present. An analysis of in vitro PLD activity in anti-PLD immunocomplexes revealed that either hypotonic (cell swelling) or hypertonic stress (cell shrinking) causes an increase in PLD1 activation but a reduction in PLD2 activity. The interplay between these two isoforms results in a predominance for PLD1 in the observed increase when measuring total PLD activity. Finally, the increase in enzymatic activity in acute hyposmotic shock is accompanied by tyrosyl phosphorylation of the PLD1 isoform, suggesting a role for protein tyrosine kinase in the control of PLD activity in response to osmotic stress.

MAP kinase upregulation after hematopoietic differentiation: role of chemotaxis

Mitogen-activated protein kinase (MAPK) isoform p42 is known to be active in exponentially growing cells at several points of the cell cycle. A high basal activity was present in three cell lines representative of immature myeloid cells tested: uHL-60, AML-14, and MPD. However, DMSO-induced differentiation of HL-60 cells (dHL-60) and subsequent expression of the neutrophilic phenotype occurred with a concomitant reduction on the basal level of MAPK activity. Simultaneously, extracellular stimuli like the cytokine granulocyte/macrophage colony-stimulating factor (GM-CSF) induced a fast (<10 min) and robust response. In terms of MAPK activity, the more mature the cell was, the higher the corresponding activity, in the three differentiation series considered: AML-14 < 3D10; MPD < G-MPD; uHL-60 < dHL-60 < neutrophils. Interestingly, peripheral blood neutrophils expressed the highest (16-fold) MAPK activation level in response to GM-CSF. Finally, using the specific MAPK inhibitor PD-98059, we demonstrated that MAPK activation is needed for neutrophil chemotaxis toward interleukin-8 and its priming by GM-CSF. Since neutrophils are terminally differentiated cells, GM-CSF does not serve a purpose in proliferation, and it must trigger the recruitment of selective signal transduction pathways particular to that final stage that includes enhanced physiological functions such as chemotaxis.

Human cell line that differentiates to all myeloid lineages and expresses neutrophil secondary granule genes

The aim of this study was to characterize a human leukemic cell line that appears capable of spontaneous differentiation to all myeloid lineages. The MPD cell line was derived using standard tissue culture techniques from the peripheral blood of a patient with an aggressive nonchronic myelogenous leukemia myeloproliferative disorder. Immunophenotyping, cytogenetic analysis, reverse transcriptase polymerase chain reaction, Northern blotting, immunoblotting, and colony assays were used to characterize the line and to assess its ability to express lineage-specific genes representative of advanced differentiation.Light microscopic morphologic analysis of the MPD cell line suggests that it has the unique property of spontaneous differentiation to mature-appearing neutrophils, macrophages, eosinophils, and basophils in proportions that approximate those found in normal bone marrow or peripheral blood. It was demonstrated that this cell line is capable of producing lineage-specific mRNA and granule proteins of at least two myeloid lineages, neutrophil and eosinophil, including neutrophil secondary granule proteins, which are not expressed in other available human cell lines. MPD cells were found to be capable of producing differentiated myeloid colonies (neutrophil, eosinophil, macrophge, mixed) in semisolid medium. The ability of MPD cells to express genetic programs associated with advanced differentiation of multiple myeloid lineages will make it a valuable tool for the study of the processes underlying lineage commitment and the regulation of expression of lineage-specific genes.

Direct inhibition of in vitro PLD activity by 4-(2-aminoethyl)-benzenesulfonyl fluoride

While conducting a purification protocol of phospholipase D (PLD) from human granulocytes, we observed that PLD activity was inhibited by a commonly-used protease inhibitor cocktail. Of the six inhibitors present in the cocktail, the serine protease inhibitor, 4-(2-aminoethyl)-benezensulfonyl fluoride (AEBSF), was found to be the sole inhibitor of PLD. AEBSF caused a loss of neutrophil and purified plant PLD activities in vitro, but not in intact cells at the concentrations used, nor did it affect the related phospholipases A(2) and C, that were utilized as specificity controls. The compound AEBSNH(2), which has the fluoride replaced by an -NH(2) group, failed to affect PLD activity as did other compounds structurally related to AEBSF with known protease inhibitory capabilities. Finally, basal- and agonist-stimulated PLD activity was inhibited in phosphatidylcholine-specific anti-PLD immunoprecipitates (IC(50) = 75 microM). These results suggest that AEBSF, in an effect probably unrelated to its anti-proteolytic ability, directly interferes with PLD enzymatic activity, making it a significant compound to begin analyzing the role of PLD in mammalian cell signaling.

Lung herniation into the neck associated with congenital absence of the sternocleidomastoid muscle

This is a case report and literature review involving congenital absence of the sternocleidomastoid muscle (SCM) and simultaneous herniation of the left lung into the neck. To date there have been eight cases of absence of the SCM muscle, but no records of lung herniation alone or in combination with SCM muscle absence. Included is the management course taken to correct this patient's defect, CAT scans of the neck, fluoroscopic imaging of the lung and neck, and photographic documentation of the defect.

Reduction mammaplasty: an outcome analysis

Reduction mammaplasty is usually performed to relieve painful symptoms and physical signs of macromastia. Justification for reduction mammaplasty should be based on the probability of relieving these clinical signs and symptoms. This retrospective study involved four surgeons who performed a variety of breast reduction procedures and was designed to determine if preoperative symptoms were resolved after reduction mammaplasty. We surveyed 285 women who had reduction mammaplasties from 1988 to 1993. Data from these surveys and the patients' charts were reviewed. A total of 185 patients (65%) returned completed surveys and were included in this study for analysis. Mean age was 40 years with an average follow-up of 3 years. The most common preoperative complaint was shoulder grooving (90%), followed by back pain (82%), shoulder pain (78%), and neck pain (65%). Average amount of breast tissue removed was 855 gm from each breast. Preoperative complaints were substantially reduced after surgery, regardless of the presurgical body mass. Most patients (97%) had improvement of symptoms, and 59% were asymptomatic. Only 3% had no change in their symptoms and none were worse. The complication rate was 45% with fat necrosis/infection being the most common complication (22%). The majority of patients (95%) were either happy or very happy with the surgery, and 98% would recommend surgery to a friend. Our data indicate that reduction mammaplasty relieves preoperative symptoms associated with macromastia.

Treatment of cleft palate associated with Robin sequence: appraisal of risk factors

Mandibular hypoplasia, airway obstruction, and a typical wide U-shaped cleft palate comprise the Robin sequence. Although much has been written regarding the treatment of these patients in the neonatal period, the literature reveals little information regarding later care of the cleft palate in these patients. The purpose of this study is to examine patients with the Robin sequence and evaluate the risk of postsurgical problems and outcome related to the neonatal period. Thirty-six patients with the Robin sequence presenting from 1972 through 1990 were reviewed. A majority of patients had feeding and respiratory difficulties, to varying degrees, following birth. These problems were treated successfully by maneuvers ranging from positioning to two infants who eventually required tracheostomy. Thirty-four patients had palate repair. Age at repair averaged 16.2 months, and one third of patients had associated anomalies. Infants who experienced problems following palatoplasty were those who had histories of severe difficulties and complications in the early months of life. In addition, patients with associated congenital anomalies has significantly more problems at the time of palate repair than those without anomalies. Those patients with the Robin sequence, who historically had minimal difficulty following birth, experienced few complications at the time of palate repair. Of the 34 patients with repaired palates, 23 demonstrated sufficient follow-up to allow for evaluation of speech outcome. Satisfactory or normal speech production was noted in 65.4%. This is not significantly different from that observed in all patients undergoing cleft palate repair during this same time period (74.9%). Secondary pharyngoplasty procedures were required in 17.4%.(ABSTRACT TRUNCATED AT 250 WORDS)

Orthognathic surgery in the cleft lip and palate patient

Orthognathic surgery for the cleft lip and palate patient should be designed to achieve good facial aesthetics and a stable, functional occlusion. Maxillary and mandibular osteotomies, which benefit cleft lip and palate patients with associated dentofacial deformities, should be modified to meet the needs of the individual patient. Soft-tissue correction of the upper lip and nose adds to the overall aesthetic result, but should be performed as a separate procedure.

Comparison of Nasometer and listener judgments of nasality in the assessment of velopharyngeal function after pharyngeal flap surgery

This study examined the relationship between nasalance scores as derived from the Model 6200 Nasometer and listener judgments of perceived nasality for individuals with pharyngeal flaps. Sixteen individuals with pharyngeal flaps read a speech sample consisting of seven sentences for which associated nasalance scores were obtained. In addition, 10 trained listeners were asked to judge the subjects' audiorecorded speech samples for the degree of both hypernasality and hyponasality using two 6-point scales. The mean judges' ratings of hypernasality did not increase systematically with increasing nasalance scores or with decreasing hyponasality ratings. However, as the nasalance scores associated with nasal loaded sentences increased, a systematic decrease in listener perception of hyponasality occurred.

One-stage closure of the entire primary palate

Timing of the closure of the anterior palate and alveolus is a subject of debate. Late repair of this defect is complicated by high fistula formation and subjects the patient to the problems of palate fistula for extended periods of time. We have utilized a single procedure performed when the child is 3 months of age that completely closes the anterior hard palate and alveolus along with the cleft lip. Our series consisted of 61 consecutive patients with unilateral clefts of the primary and secondary palate. Mucosal turnover flaps from the vomer along with lateral nasal mucosal flaps provide the nasal lining. A buccal sulcus flap with a Veau flap completes the oral repair. Ninety-five percent (58 of 61) of the patients had complete and stable closure of their anterior palate and alveolus after 1 year. The incidence of fistula formation in our series (3 of 61) is much lower than that reported with the utilization of other protocols. Excellent exposure of the anterior palate and alveolar defect during lip repair, early restoration of anatomic relationships, establishment of a good nostril floor and sill, and very low fistula formation are among the benefits of this procedure. The increase in operative time is considered minimal in light of aforementioned advantages.

Surgical-orthodontic correction of transverse maxillary deficiency

A conservative osteotomy of the zygomaticomaxillary buttress in combination with a rapid palatal expansion appliance is a dependable technique for the treatment of horizontal maxillary deficiency in adults. This procedure has been used successfully in 56 patients in our series, but 17 patients (30 per cent) required a midpalatal osteotomy. In two patients, overexpansion was not achieved because of necrosis of the mucosa. In three other patients, expansion had to proceed at a slower pace because of mucosal ulceration. There have been no other complications. The procedure is indicated mainly in those patients with a horizontal deficiency who do not require subsequent surgery, but for some patients it may be the preliminary procedure. Twelve patients (21 per cent) had subsequent orthognathic surgery. Follow-up has been from 1 to 12 years and there has been no relapse. In our opinion, the zygomaticomaxillary buttress is the primary area of resistance to lateral movement of the maxilla by rapid maxillary expansion appliances.

Surgical-orthodontic correction of transverse maxillary deficiency

A conservative osteotomy of the zygomaticomaxillary buttress in combination with a rapid palatal expansion appliance is a dependable technique for the treatment of horizontal maxillary deficiency in adults. This procedure has been used successfully in 56 patients in our series, but 17 patients (30 percent) required a midpalatal osteotomy. In two patients, overexpansion was not achieved because of necrosis of the mucosa. In three other patients, expansion had to proceed at a slower pace because of mucosal ulceration. There have been no other complications. The procedure is indicated mainly in those patients with a horizontal deficiency who do not require subsequent surgery, but for some patients it may be the preliminary procedure. Twelve patients (21 per cent) had subsequent orthognathic surgery. Follow-up has been from 1 to 12 years and there has been no relapse. In our opinion, the zygomaticomaxillary buttress is the primary area of resistance to lateral movement of the maxilla by rapid maxillary expansion appliances.

Mandibular prognathism

The use of the vertical subcondylar osteotomy for correction of uncomplicated mandibular prognathism is reviewed. Techniques for use in more complicated cases such as when a set back of greater than 10 mm is required are also described.

Soft-tissue manifestations of aesthetic defects of the jaws: diagnosis and treatment

Treatment planning for patients with dentofacial deformities should include a skeletal and a soft-tissue analysis. This article collates and summarizes several different soft-tissue analyses. In addition, it correlates the anticipated soft-tissue profile changes with various skeletal and soft-tissue surgical procedures.

Management of dog bite avulsions of the lip vermilion

A conservative approach allowing the wounds to heal by secondary intention has been used in 14 patients. The results have been very satisfactory, and only six of the 14 patients required minor scar revisions.

The syndrome of inappropriate secretion of antidiuretic hormone in the pharyngeal flap operation

A prospective study was undertaken to determine whether there was a relationship between the pharyngeal flap operation and the syndrome of inappropriate secretion of antidiuretic hormone (SIADH). From August 1982 to November 1983, 25 patients underwent pharyngeal flap procedures. They were compared to a control group made up of five patients who underwent major cleft lip revisions. Twelve of the twenty-five patients (48%) who underwent pharyngeal flap procedures had inappropriately elevated serum ADH levels, low serum osmolality, and hyponatremia in the postoperative period. There was a statistically significant (p less than 0.001) drop in the serum sodium levels in the pharyngeal flap group from the preoperative to postoperative period. There was neither a statistically significant change in the serum sodium levels nor inappropriate elevation of ADH levels in the control group. Two patients who underwent pharyngeal flap procedures developed SIADH. To our knowledge this complication has not been reported in association with the pharyngeal flap operation. No specific causes were found that would explain why SIADH developed.

Surgical orthodontic correction of transverse maxillary deficiency: a simplified approach

Osteotomy of the zygomaticomaxillary buttress in combination with a rapid palatal exapnsion appliance is a dependable technique for the treatment of horizontal maxillary deficiency in adults. This procedure has been used in 18 patients with excellent expansion in 17. In one patient, expansion was discontinued prior to overcorrection because of pressure necrosis on the palate related to the appliance. This was the only complication. The procedure is indicated mainly in those patients with a horizontal deficiency who do not require subsequent surgery, but for some patients it may be the preliminary procedure. Three patients in this series had subsequent orthognathic surgery. Follow-up has been from 1 to 6 years, and there has been no relapse. In our opinion, the zygomaticomaxillary buttress is the primary area of resistance to lateral movement of the maxilla by rapid maxillary expansion appliances.

The combined surgical and orthodontic treatment of mandibular prognathism

Patients with severe mandibular prognathism are best managed with a combined orthodontic-surgical approach. In our patients, the orthodontic treatment consisted of six to eighteen months of presurgical preparation, which in some patients may accentuate the dental deformity. This is done to provide two well-aligned dental arches that will fit accurately at surgery. The surgical procedure used was an oblique subcondylar osteotomy. This was followed by six to eight months of orthodontic treatment to complete dental alignment. Thirty patients were treated using this combined approach, with excellent results and few complications.

Does infection play a role in breast capsular contracture?

The formation of capsular contracture around silicone implants continues to be the most common complication of augmentation mammaplasty. To date, the etiologic factors in the formation of capsular contractures have remained inconclusive. In the present study, the role of subclinical infection with S. epidermidis as a cause of capsular contracture was evaluated in 16 rabbits using miniature silicone implants. All the implants on the side contaminated with varying concentrations of S. epidermidis developed breast capsular contractures. Using Baker's classification, they were graded III or IV, while the controls were all considered to be either grade I or II. Grossly, the capsules on the contaminated side were firm, fibrous, and 2 to 3 times thicker than the controls, and this was confirmed histologically using micrometry. Implants contaminated with 10(7) bacteria uniformly extruded. The present study seems to indicate that subclinical infection with Staphylococcus epidermidis may be one of the causes of capsular contracture around breast implants.

Surgical intervention in complications of acute leukemia

Aggressive chemotherapy has dramatically increased the number and duration of remissions in acute leukemia. Concomitant with improved survival has been an increased incidence of complications necessitating surgery in patients with chemotherapy-induced pancytopenia. In the past, patients such as the three described here rarely survived, whether managed conservatively or surgically. All three of these achieved partial or complete remisson. In view of our experience plus reports in the literature, we feel that aggressive surgical intervantion can result in a greater percentage of patients surviving the complications of therapy, and this in turn can lead to a higher incidence of complete remission.

The effects of Surgicel on bone formation

The subperiosteal implantation of Surgicel has been advocated for the stimulation of bone formation by some authors. A clinical trial in five patients demonstrated no radiographic evidence of bone formation after 12 months. An experimental model was designed in the rabbit. This study also demonstrated no radiographic or histologic evidence of bone formation with the use of subperiosteal Surgicel. The further use of Surgicel for the stimulation of bone formation is not recommended.