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Biomedical subjects

J B Robinson

Publications and source records attributed to J B Robinson.

At least 19 recordsLinked to original sources
PubMed2001

Hypersensitivity reactions and the utility of oral and intravenous desensitization in patients with gynecologic malignancies.

OBJECTIVES: The aims of this study were to characterize hypersensitivity reactions to chemotherapy in patients with gynecologic malignancies and to determine the utility of oral and intravenous desensitization. METHODS: We retrospectively reviewed patients with hypersensitivity reactions identified by direct physician query and by review of charts with ICD9 code E933.1 (Adverse Effect Anti-Neoplastic). RESULTS: Thirty-two patients were identified: 27 with ovarian cancer, 4 with primary peritoneal cancer, and 1 with cervical cancer. Nine patients experienced hypersensitivity reactions during the primary regimen and 23 during chemotherapy for recurrent disease. Hypersensitivity occurred following an average of nine courses. Hypersensitivity occurred secondary to paclitaxel (10) carboplatin (16), cisplatin (4), bleomycin (1), and paclitaxel/carboplatin combination therapy (1). Patients had previously received the agent in 93.8% of carboplatin reactions, in 54.5% of paclitaxel reactions, and in all other agent reactions. Hypersensitivity reactions most commonly included flushing, dyspnea/bronchospasm, back pain, chest discomfort, pruritus, erythema, and nausea and occasionally included alterations in blood pressure or pulse rate. Reactions were successfully treated in 96.9% of patients by interrupting the infusion and administering steroids, antihistamines, benzodiazepines, nebulized beta-agonists, and/or pressors. Seventeen patients underwent desensitization, one to two agents, with 94% success. Nine of ten patients had successful iv desensitization, and 8/10 patients had successful oral desensitization. One failure on the oral regimen had previous successful iv desensitization. CONCLUSIONS: Hypersensitivity reactions to chemotherapeutic agents do not necessarily require exclusion of a compound from the treatment regimen. Intravenous and oral desensitization protocols are useful for successful and safe administration of paclitaxel and platinum compounds in patients with prior hypersensitivity reactions.

Administration, Oral↗
PubMed2000

Blockade of nuclear factor-kappaB signaling inhibits angiogenesis and tumorigenicity of human ovarian cancer cells by suppressing expression of vascular endothelial growth factor and interleukin 8.

We determined whether blockade of nuclear factor (NF)-kappaB/relA activity in human ovarian cancer cells can suppress angiogenesis and growth in an orthotopic nude mouse model. The human ovarian cancer cells SKOV3ip.1 and HEY-A8 were transfected with a mutated IkappaBalpha (IkappaBalphaM), ie., resistant to phosphorylation and degradation, and hence blocks NF-kappaB activity. NF-kappaB signaling blockade significantly inhibited in vitro and in vivo expression of two major proangiogenic molecules, vascular endothelial growth factor and interleukin 8, in cultured cells and in cells implanted into the peritoneal cavity of nude mice. The decreased expression of vascular endothelial growth factor and interleukin 8 directly correlated with decreased tumorigenicity, decreased vascularization of lesions, decreased formation of malignant ascites, and prolonged survival of mice. These findings suggest that inhibition of NF-kappaB/relA activity in ovarian cancer cells can suppress angiogenesis and progressive growth.

Animals↗
PubMed2000

The use of paclitaxel and cisplatin in a patient with epithelial ovarian cancer and human immunodeficiency virus.

OBJECTIVE: Several spots exist of human immunodeficiency virus (HIV)-positive patients developing epithelial ovarian cancer. The optimal chemotherapeutic regimen has been unclear due to potential immunotoxicity from chemotherapy in these already immunocompromised patients. This is the first report of paclitaxel-based combination chemotherapy in an HIV-positive patient with ovarian cancer. METHOD: A 39-year-old woman with HIV was diagnosed with poorly differentiated serous carcinoma. She underwent optimal cytoreductive surgery and received six courses of paclitaxel and cisplatin. RESULTS: The patient experienced a complete clinical response to therapy with no adverse effect on surrogate markers for human immunodeficiency virus (CD4 count, beta2 microglobulin, neopterin, p24 antigen, and viral load). CONCLUSION: Paclitaxel- and platinum-based chemotherapy, the standard of care for adjuvant chemotherapy in advanced ovarian carcinoma, is appropriate therapy for ovarian cancer patients with HIV. There is no evidence that the paclitaxel/cisplatin regimen is associated with progression of HIV or increased chemotherapy-associated morbidity.

Adult↗
PubMed2000

Cavitational ultrasonic surgical aspiration for the treatment of vaginal intraepithelial neoplasia.

OBJECTIVE: The aim of this study is to determine whether cavitational ultrasonic surgical aspiration (CUSA) is effective and safe for treating vaginal intraepithelial neoplasia (VAIN). METHODS: We conducted a retrospective chart review of 46 patients who were treated with CUSA for VAIN in a single gynecologic oncology practice between 1981 and 1999. RESULTS: At initial presentation, 39% of treated patients had grade I VAIN, 20% had grade II, and 41% had grade III. The mean duration of follow-up from initial CUSA treatment was 21 months. Twenty-nine patients (63%) were initially treated with CUSA, 7 patients (15%) with laser vaporization, 7 patients (15%) with surveillance by Papanicolaou smear, 1 patient (2%) with partial vaginectomy, 1 patient (2%) with 5-fluorouracil, and 1 patient (2%) with loop excision. Patients initially treated with CUSA had a higher percentage of grade III VAIN at diagnosis (48%) than did patients initially treated with other methods (29%). A significantly greater proportion of patients initially treated with CUSA had no recurrence of VAIN (66%) compared with patients initially treated with other methods (0%) (P < 0.0001). A significantly greater proportion of patients who were treated for recurrent disease with CUSA had no further recurrence (52%) compared with patients treated for recurrent disease with other methods (9%) (P < 0.001). No patient treated with CUSA reported adverse effects; 7 patients treated with other methods reported dysuria, burning, and pain. CONCLUSION: These initial data suggest that CUSA is a safe and effective method for treating VAIN and may be an appropriate treatment for many patients.

Adolescent↗
PubMed2000

Plants secrete substances that mimic bacterial N-acyl homoserine lactone signal activities and affect population density-dependent behaviors in associated bacteria.

In gram-negative bacteria, many important changes in gene expression and behavior are regulated in a population density-dependent fashion by N-acyl homoserine lactone (AHL) signal molecules. Exudates from pea (Pisum sativum) seedlings were found to contain several separable activities that mimicked AHL signals in well-characterized bacterial reporter strains, stimulating AHL-regulated behaviors in some strains while inhibiting such behaviors in others. The chemical nature of the active mimic compounds is currently unknown, but all extracted differently into organic solvents than common bacterial AHLs. Various species of higher plants in addition to pea were found to secrete AHL mimic activities. The AHL signal-mimic compounds could prove to be important in determining the outcome of interactions between higher plants and a diversity of pathogenic, symbiotic, and saprophytic bacteria.

4-Butyrolactone↗
PubMed2000

Patency of different arterial and venous end-to-side microanastomosis techniques in a rat model.

Microvascular anastomotic patency is the most important factor in determining a successful outcome in free-flap transfers. End-to-end and end-to-side techniques have been shown to provide equivalent arterial patency rates in clinical and basic science studies, and end-to-side anastomoses have been used extensively in microsurgical reconstruction. Nevertheless, the effect of venotomy shape on the patency of venous end-to-side anastomoses has not been previously reported. The purpose of this study was to compare the patency rates of end-to-side anastomoses using different techniques in both arteries and veins. In total, 104 Sprague-Dawley rats were subdivided into four groups. The rats were anesthetized, and anastomosis was performed on either the femoral artery or vein on the right with the left used as control. Vesselotomy was varied between an end-to-side hole and an end-to-side slit with patency measured immediately following surgery and at 2 weeks. No significant difference in patency or histology between these techniques was demonstrated in any group. We conclude there is no difference in patency rate between the two techniques in arterial or venous vesselotomies; however, in small vessels < 1.5 mm, the slit technique is technically easier, and clinical recommendations are given.

Anastomosis, Surgical↗
PubMed2000

Importance of the depressor septi nasi muscle in rhinoplasty: anatomic study and clinical application.

An active depressor septi muscle can accentuate a drooping nasal tip and shorten the upper lip on animation. We have found that dissection and transposition of the depressor septi muscle during rhinoplasty can improve the tip-upper lip relationship in appropriately selected patients. Although the anatomy of the depressor septi muscle has been described, the anatomic variations of this muscle have not been previously reported. The goals of this study were two-fold: (1) to define the anatomic variations of the depressor septi muscle using 55 fresh cadaver dissections and (2) to develop a clinically applicable algorithm for modification of this muscle during rhinoplasty in those patients with a short upper lip and/or tip-upper lip imbalance. Fifty-five fresh cadavers were dissected, and the anatomic variations of the depressor septi muscle were recorded. Three variations of the depressor septi muscle were delineated: type I inserted fully into the orbicularis oris (62 percent); type II inserted into the periosteum and incompletely into the orbicularis oris (22 percent); and type III showed no, or rudimentary, depressor septi muscle (16 percent). Sixty-two patients over a 4-year period (from 1995 to 1999) were identified preoperatively with a hyperactive depressor septi diagnosed by a descending nasal tip and shortened upper lip on animation. These patients underwent dissection and transposition (not resection) of the paired depressor septi during rhinoplasty with improvement or correction of the tip-upper lip imbalance in 88 percent of cases. The anatomic study, surgical indications, rationale for the operative technique, and clinical cases are presented. Dissection and transposition of the depressor septi is a valuable adjunct to rhinoplasty in patients with a type I or II muscle variant.

Adult↗
PubMed1999

Extraovarian granulosa cell tumor.

OBJECTIVE: The aim of this study was to report a case of extraovarian granulosa cell tumor and to describe its relevance to the histologic origin of granulosa cell tumors and to clinical practice. METHODS: The clinical course and histopathology of the case were reviewed, and a literature search for other reported cases was performed. RESULTS: A 67-year-old woman presented with postmenopausal bleeding and a pelvic mass. Laparotomy revealed a 16-cm mass arising from the right pelvic sidewall, filling the pelvis, and involving the bladder and rectosigmoid colon. Both ovaries appeared normal and were separate from the mass. Pathologic examination revealed granulosa cell tumor. A literature search revealed no recently reported cases of extraovarian granulosa cell tumor. CONCLUSIONS: Granulosa cell tumors can arise in locations other than the ovary and may be derived from the mesenchyme of the genital ridge. Women who have undergone oophorectomy may have the potential to develop granulosa cell tumors.

Aged↗
PubMed1999

The rate of warping in irradiated and nonirradiated homograft rib cartilage: a controlled comparison and clinical implications.

Irradiated homograft costal cartilage reportedly warps less than autologous cartilage based on clinical observation; however, no controlled, experimental studies on the warping characteristics of irradiated homograft costal cartilage have been done. Fresh cadaver costal cartilage (ribs 5 through 8) was prepared and irradiated using a standardized technique. A specially designed cartilage-cutting device was used to cut the cartilage into a reproducible size. The irradiated (n = 23) and nonirradiated (n = 20) groups were incubated in vitro and assessed over a 4-week period. There was no significant difference in warping between the irradiated and nonirradiated groups (p = 0.1). The centrally cut pieces of cartilage in each group warped less than peripherally cut blocks in each group. Peripherally cut pieces of both the irradiated and nonirradiated groups warped at a faster rate compared with the nonirradiated groups. All cartilage exhibited continued warping over the 4-week study period. We concluded that there was no difference in warping characteristics between irradiated and nonirradiated homograft rib cartilage. Furthermore, unlike previous studies, cartilage grafts continued warping over time for at least 4 weeks, and this phenomenon may be extrapolated as a causative factor in delayed postoperative nasal deviation after rhinoplasty and nasal reconstruction where rib grafts are used.

Adult↗
PubMed1999

The blood supply of the reverse temporalis muscle flap: anatomic study and clinical implications.

Although the reverse temporalis muscle flap has been used clinically, the exact vascular connection between the superficial and deep temporal vessels has not been clearly defined. The purpose of this study was to investigate the vascular territory of the reverse temporalis muscle supplied by the superficial temporal vessels. Six cadaver heads were studied using a colored lead oxide injection through the superficial temporal artery. The specimens were examined macroscopically and radiographically. The reverse temporalis muscle flap was then applied to a clinical case presenting with traumatic anterior skull base defect communicating with the nasal cavity. The cadaver specimens demonstrated that the superficial temporal artery formed an average 1.3 +/- 0.2 cm in width of dense vascular zone, which was located within 1.8 cm below the superior temporal line. The dense vascular network further perfused the anterior and posterior deep temporal arteries and the muscular branch of the middle temporal artery to supply the temporalis muscle. The mean perfused area of the temporalis muscle was 83 percent, ranging from 79 to 89 percent, in five cadaver heads. One cadaver revealed only 55 percent of perfused area in the absence of the muscular branch of the middle temporal artery. The consistent area without perfusion was located in the distal third of the posterior portion of the reverse temporalis muscle. In clinical cases, the reverse temporalis muscle flap was used successfully to obliterate the anterior skull base defect without evidence of muscle flap necrosis. The exact blood supply to the distal third of the posterior portion of the reverse temporalis muscle flap needs to be investigated further in vivo. Particular attention was paid to the inclusion of the muscular branch of the middle temporal artery in this flap to augment the blood supply to the temporalis muscle.

Adult↗
PubMed1999

Sensory changes after traditional and ultrasound-assisted liposuction using computer-assisted analysis.

Postoperative sensory changes (i.e., hypesthesias) that occur after suction-assisted lipoplasty (SAL) are expected clinical sequelae. These disturbances usually return to normal within several weeks to months postoperatively. The presumed mechanism of injury is direct trauma to the peripheral nerves from the suction cannula. In addition, the potential for demyelination of peripheral nerves secondary to cavitation during ultrasound-assisted liposuction (UAL) is well known. Quantitative data describing hypesthesia after both procedures are limited. The purpose of this study was to objectively evaluate the severity and duration of postoperative hypesthesia after liposuction to better educate patients preoperatively. Furthermore, the authors use the three-stage UAL technique and wanted to determine whether a clinical difference in sensory return existed between suction- and ultrasound-treated areas. A total of 21 patients underwent liposuction performed by the senior author (RJ.R.). The abdomen, flanks, thighs, and medial knees were tested for objective sensation with the Pressure Specified Sensory Device preoperatively and at 2, 6, and 10 weeks postoperatively. A total of 102 sites were tested. On average, the SAL-treated areas improved to normal sensation by 6 weeks, whereas the UAL-treated areas took, on average, 10 weeks to recover. The severity of the hypesthesia was not correlated with larger aspiration volumes or longer UAL exposure time per site. At 10 weeks, 90 percent of UAL-treated patients and 89 percent of liposuction patients overall had recovered normal sensation. This study provides the body-contouring surgeon with good, objective data with which to educate patients regarding sensory return after liposuction.

Abdomen↗
PubMed1999

Factors predictive of quality of life after silicone-implant explanation.

'Medical records of 180 patients who underwent silicone gel-filled breast implant explanation were retrospectively reviewed. The goal of this study was to determine if any patient variable(s) had predictive value for positive quality of life after explanation. The medical complaints, symptoms, and established diagnoses were considered equally and were referred to as self-reported medical problems. The study revealed that no single problem or pairing of problems was associated with or predictive of outcome. The results show, however, that the number of medical problems was significantly predictive of patient perception of quality of life. A total of 50 explanation patients completed quality-of-life surveys. Specifically, those patients who reported five or fewer medical problems that predated explantation were significantly more likely to perceive an increased quality of life after surgery than those who reported nine or more medical problems (p < 0.04). In conclusion, it is difficult to correlate subjective patient symptoms with postoperative improvements in quality of life after explantation.

Attitude to Health↗
PubMed1999

Roles of Pseudomonas aeruginosa las and rhl quorum-sensing systems in control of twitching motility.

Pseudomonas aeruginosa is a ubiquitous environmental bacterium and an important human pathogen. The production of several virulence factors by P. aeruginosa is controlled through two quorum-sensing systems, las and rhl. We have obtained evidence that both the las and rhl quorum-sensing systems are also required for type 4 pilus-dependent twitching motility and infection by the pilus-specific phage D3112cts. Mutants which lack the ability to synthesize PAI-1, PAI-2, or both autoinducers were significantly or greatly impaired in twitching motility and in susceptibility to D3112cts. Twitching motility and phage susceptibility in the autoinducer-deficient mutants were partially restored by exposure to exogenous PAI-1 and PAI-2. Both twitching motility and infection by pilus-specific phage are believed to be dependent on the extension and retraction of polar type 4 pili. Western blot analysis of whole-cell lysates and enzyme-linked immunosorbent assays of intact cells were used to measure the amounts of pilin on the cell surfaces of las and rhl mutants relative to that of the wild type. It appears that PAI-2 plays a crucial role in twitching motility and phage infection by affecting the export and assembly of surface type 4 pili. The ability of P. aeruginosa cells to adhere to human bronchial epithelial cells was also found to be dependent on the rhl quorum-sensing system. Microscopic analysis of twitching motility indicated that mutants which were unable to synthesize PAI-1 were defective in the maintenance of cellular monolayers and migrating packs of cells. Thus, PAI-1 appears to have an essential role in maintaining cell-cell spacing and associations required for effective twitching motility.

Bacterial Adhesion↗
PubMed1999

Vulvar porokeratosis: case report and review of the literature.

We report the first case of vulvar porokeratosis that occurred in a 39-year-old woman with a 30-year history of vulvar pruritus and disfiguring vulvar lesions. Ultrasonic surgical aspiration resulted in resolution of her pruritus and excellent cosmesis. Light microscopy revealed characteristic cornoid lamellae and electron microscopy confirmed the diagnosis of vulvar porokeratosis.

Adult↗
PubMed1999

Stem cell function and engraftment is not affected by "in vivo purging" with rituximab for autologous stem cell treatment for patients with low-grade non-Hodgkin's lymphoma.

The chimeric anti-CD20 monoclonal antibody rituximab (Rituxan; IDEC Pharmaceuticals, San Diego, CA, and Genentech, Inc, San Francisco, CA) has recently been approved by the US Food and Drug Administration as single-agent treatment of relapsed/refractory low-grade or follicular non-Hodgkin's lymphoma. Initial results from the pivotal clinical trial revealed that response rates to rituximab were higher in patients who previously had high-dose therapy and autologous stem cell transplantation. We have initiated a clinical trial that combines the use of rituximab with high-dose chemotherapy followed by autologous stem cell transplantation for patients with chemosensitive relapsed follicular small cleaved or mantle cell lymphoma. A unique feature of this study is that in addition to eight maintenance infusions of rituximab after autologous stem cell transplantation, patients also received rituximab 375 mg/m2 2 days before a granulocyte colony-stimulating factor-mobilized stem cell collection as "in vivo purge." We report on preliminary results demonstrating the safety and efficacy of the in vivo purge on 10 patients undergoing stem cell mobilization, nine of whom have already undergone transplantation. The peripheral blood CD34+ counts were 14.92 and 20 x 10(6)/L on day 4 and day 5, respectively, of the stem cell mobilization with granulocyte colony-stimulating factor. This compares with 11.7 and 11.8 x 10(6)/L, respectively, for the control population. The median CD34 stem cell yield in the graft collection was 3.7 x 10(6)/kg in patients receiving rituximab in vivo purge compared with 3.1 x 10(6)/kg in the control population. The target stem cell collection was successfully collected in six of 10 patients in a 1-day single large-volume leukapheresis collection, while two patients required 2 days and the last two patients required 3 days. Functional assays revealed the stem cell colony-forming unit-granulocyte monocyte and burst-forming unit-erythrocyte to be 55 and 44 colonies per plate, respectively, for the patients receiving the in vivo rituximab purge. This compares favorably with 37 and 38.5 colonies per plate, respectively, for the control population. Neutrophil engraftment took a median of 11 days for both cohorts; platelet independence was achieved in 8 days compared with 10 days for the control population. The median number of platelet transfusions was two for patients receiving rituximab and 2.5 for the control group. Assessment of serum cytokines immediately before the rituximab infusion during the stem cell mobilization and immediately after revealed a twofold to sevenfold increase in interleukin-1beta, tumor necrosis factor-alpha, and interleukin-6. The polymerase chain reaction analysis for minimal residual disease in stem cell collections and in peripheral blood and bone marrow samples of these patients will help to determine the efficacy of rituximab in vivo purge on disease progression.

Adult↗
PubMed1998

Lipid infiltration as a possible biologic cause of silicone gel breast implant aging.

The cause of silicone gel implant aging and rupture is not known. Recent reports indicate the failure rate is higher than previously published, and implant aging and rupture may be due to progressive mechanical deterioration of the outer vulcanized silicone shell. It is known that lipids are absorbed by the hydrophobic silicone elastomer, and lipid infiltration causes mechanical attenuation and possible failure of the elastomer. The purposes of this article are to analyze the silicone envelope/gel of explanted prostheses and the silicone elastomer of other medical grade silicone devices for lipid content and to suggest its possible role in implant aging and rupture. We assayed 33 ruptured silicone breast implant shells (mean age 13.1 years; range 8 to 26 years) and 8 medical grade silicone elastomer devices (mean age 3.7 years; range 3 months to 12 years) for evidence of lipid infiltration using thin layer chromatography. These were compared with control group assays from two nonimplanted silicone gel implants and one unused Silastic catheter. Ninety-eight percent of implants and other previously implanted silicone devices were found to have evidence of lipid infiltration compared with none in nonimplanted controls (p < 0.005). We conclude that lipids infiltrate the outer silicone shell and may be a factor related to breast implant aging and rupture due to progressive mechanical weakening of the outer silicone shell.

Breast Implantation↗