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Biomedical subjects

L Martin

Publications and source records attributed to L Martin.

At least 289 records · Page 16Linked to original sources
PubMed1996

Laparoscopic fibrin glue ureteral anastomosis: experimental study in the porcine model.

Laparoscopic suturing is still difficult and time-consuming. The aim of this study, using the porcine model, was to evaluate the feasibility, safety, and efficacy of laparoscopic fibrin glue ureteral anastomosis without stay sutures for approximating the ureteral ends. In five pigs, after bilateral cystoscopic insertion of a 7F ureteral catheter, each upper ureter was laparoscopically dissected free and transected with scissors. The ureteral ends were then approximated with two atraumatic grasping forceps, and the fibrin glue was applied over the anastomotic site using a specially designed catheter (Duplocath). After waiting 5 minutes for the sealant to adhere, the forceps were removed, and the anastomotic site was examined for any early disruption. The ureteral stents were then pulled back to the distal ureter, and retrograde ureteropyelography was accomplished bilaterally in order to assess the immediate patency of the anastomoses. The animals were sacrificed and the ureteral anastomoses surgically removed for histologic examination. The operative time after insertion of the trocars averaged 15 minutes for each anastomosis, and no early disruption was observed after withdrawal of the grasping forceps. Immediate ureteral fluoroscopic patency was achieved in all 10 ureteral anastomoses, without leakage in 8 and with minimal leakage in 2. Histologic examination revealed a mild inflammatory reaction in the serosa with no modifications of the mucosa or the muscularis. Subsequently, two pigs were subjected to the same procedure bilaterally and not sacrificed. These two animals died with enormous urinomas on postoperative days 6 and 8. In each case, the anastomotic site was completely disrupted on one side, while the other side remained grossly patent. However, histologic examination of these latter anastomoses revealed no real coaptation of the ureteral ends, while demonstrating complete eversion of the mucosa. In conclusion, fibrin glue ureteroureterostomies, although easy to accomplish, are not safe enough to be used without stay sutures in laparoscopic surgery.

Anastomosis, Surgical↗
PubMed1996

Construction and expression of bi-functional proteins of single-chain Fv with effector domains.

We fused various polypeptide extensions to the C-termini of single chain Fv (scFv) and disulfide-stabilized Fv (dsFv) fragments to facilitate detection of bi-functional proteins or to add biological effector domains, which included the human metallothionein (HMT) motif and biotin mimetic sequence. These bi-functional proteins were expressed and secreted in a recombinant Pichia pastoris system and showed specific anti-idiotype binding activity, as determined by competitive radioimmunoassaying. However, the fusion protein constructed with dsFv- HMT, but not scFv-HMT, had lost this binding activity. The interruption of the structural conformation as a result in dsFv-HMT may be explained by the interactions between the cysteines engineered in dsFv domains and the cysteines in the HMT region.

Amino Acid Sequence↗
PubMed1996

Single-blind study of the effects of intravenous dolasetron mesylate versus ondansetron on electrocardiographic parameters in normal volunteers.

A single-blind, randomized, five-way cross-over, safety and tolerability trial was conducted to determine whether intravenous (i.v.) dolasetron mesylate at varying single doses induces changes in ECG intervals in healthy volunteers and to compare these changes with a single intravenous dose of ondansetron or placebo. Thirty healthy male volunteers received 1.2, 1.8, and 2.4 mg/kg i.v. dolasetron mesylate, 32 mg i.v. ondansetron, and placebo on 5 separate days. ECGs were recorded at intervals during the 24 h after study drug administration. The changes in ECG intervals observed after dolasetron mesylate or ondansetron were acute, transient, and asymptomatic. Dolasetron mesylate resulted in slight but statistically significant dose-related increases in heart rate (HR) and PR and QRS intervals (between h 0 and 4). A statistically significant increase in QTc interval was detected with both dolasetron mesylate (2.4 mg/kg) and ondansetron. Ondansetron also produced a slight but statistically significant increase in JT interval and a decrease in HR. These changes in ECG intervals were usually observed between h 0 and 4; all parameters returned to baseline within 8 h of treatment. The results demonstrate that both dolasetron mesylate and ondansetron prolong the QTc interval. However, dolasetron mesylate predominantly altered ECG parameters indicative of ventricular depolarization (QRS duration), whereas ondansetron predominantly affected ventricular repolarization as measured by a prolongation in the JT interval. Both dolasetron and ondansetron were well tolerated. The adverse event (AE) rate was 13.3% (4 of 30); all AE were of mild or moderate severity and were distributed across all dose arms.

Adult↗
PubMed1996

1,000 consecutive ultrasounds for blunt abdominal trauma.

Diagnostic peritoneal lavage (DPL) and computed tomography (CT) are the primary diagnostic modalities used in the evaluation of patients with suspected blunt abdominal trauma (BAT). DPL is fast and accurate but is associated with complications. CT is also accurate, yet requires stability and transportability of the patients. Ultrasound (US) has been suggested as an aid in evaluating BAT. We evaluated US in the initial assessment of BAT in 1000 patients. Patients were eligible for the study if they met specified trauma criteria and had suspected BAT. We then followed the outcome of the patients and their further work-up. US showed a sensitivity of 88%, a specificity of 99%, and an accuracy of 97% for detecting intraabdominal injuries. We conclude that emergency ultrasound may be used as the initial diagnostic modality for suspected blunt abdominal trauma.

Abdominal Injuries↗
PubMed1996

Congenital nasal comedones--report of three cases.

We report on three patients with black or white comedones arranged along the nasal groove in the distal third of the nose between the alar and triangular cartilages. This peculiar disorder is probably more common than would appear from the small number of cases so far reported in the literature.

Acne Vulgaris↗
PubMed1996

Cytokine mRNA changes during the treatment of hypertrophic scars with silicone and nonsilicone gel dressings.

BACKGROUND: Treatment of hypertrophic scars can be difficult for both patients and physicians. Silicone-containing gel dressings have been reported to be an effective alternative treatment for hypertrophic scars, yet the mechanism of action of these dressings is unknown. OBJECTIVE: To determine whether silicone is an essential factor in the treatment of hypertrophic scars and investigate the effects of occlusive dressing therapy on the expression of key wound healing mediators. METHODS: A pilot paired comparison, nonrandomized study was conducted comparing a silicone gel sheeting (Silastic [SGS]) with a hydrogel dressing (ClearSite). The effects of the dressings were compared side by side in the treatment of 15 hypertrophic scars at both the clinical and molecular levels through the use of reverse transcriptase/polymerase chain reaction to evaluate effects on the expression of interleukin 8 (IL-8), basic fibroblast growth factor (bFGF), granulocyte-macrophage colony-stimulating factor (GMCSF), epidermal growth factor (EGF), transforming growth factor beta (TGF-beta), and fibronectin. RESULTS: Comparable clinical improvement of the hypertrophic scars was obtained with both dressings. Treatment of hypertrophic scars resulted in increased mean levels of IL-8, bFGF, and GMCSF mRNA; while mean TGF beta and fibronectin mRNAs decreased after treatment with both dressings. Comparison between the two dressings revealed significant changes in IL-8 and fibronectin mRNA levels after treatment with ClearSite, while only fibronectin changes were significant after treatment with SGS with respect to normal skin. Only ClearSite induced significant changes in IL-8 and bFGF levels when untreated scars were compared with posttreatment lesions, suggesting that the hydrogel augments collagenolysis via promotion of inflammation. CONCLUSIONS: This study demonstrates that silicone is not a necessary component of occlusive dressings in the treatment of hypertrophic scars. The pathogenesis of hypertrophic scars is further elucidated by demonstrating that there is molecular evidence for extensive connective tissue remodeling occurring during occlusive dressing therapy.

Adult↗
PubMed1996

Will it be feasible to insert endoprostheses under interventional MRI?

PURPOSE: Recent advances in magnetic resonance imaging (MRI) technology may provide a safer and more sensitive monitoring modality than X-ray imaging for endovascular surgical procedures. The purpose of this study was to investigate the feasibility of using MRI to monitor the insertion of endoprostheses. METHODS: The endoprostheses we studied were composed of a nitinol stent encased in a polyester sheath. These were characterized with four different MRI techniques: the fast spin-echo; spin-echo; gradient-recalled echo; and the spoiled gradient-recalled echo. The deployment of the endoprosthesis into an artery was simulated in an in vitro model and viewed using a fast spin-echo MRI technique. RESULTS: Image artifacts produced by the nitinol framework in these endoprostheses were minimal when fast spin-echo or spin-echo imaging techniques were used, improving the visibility of the device. In in vitro tests, the catheters and endoprostheses were visualized by MRI with sufficient clarity to guide the placement of a device in the model artery. CONCLUSIONS: Insertion of this type of endoprosthesis under interventional MRI guidance is feasible. The convenience and improved safety provided by interventional MR systems and "real-time" imaging capabilities are expected to make this technology an attractive alternative to X-ray imaging techniques.

Alloys↗
PubMed1996

Evaluating blunt abdominal trauma:role for ultrasonography.

Patients in unstable condition with suspected blunt abdominal trauma require rapid evaluation to assess the need for laparotomy. Ultrasonography is fast and uses portable equipment, and it can be used in the resuscitation area to detect free intraperitoneal fluid as an indication of intraabdominal injury in the patient in unstable condition. To determine the utility of emergency abdominal sonography for evaluating patients with blunt abdominal trauma, a prospective study was designed to compare ultrasonography to diagnostic peritoneal lavage. Emergency sonography was performed prior to diagnostic peritoneal lavage on 54 acutely injured patients in the resuscitation area. Our results reveal that ultrasonography has a sensitivity of 87%, a specificity of 100%, and an overall accuracy of 96% for detecting free intraperitoneal fluid. We conclude that ultrasonography is a reliable method for the emergent evaluation of blunt abdominal trauma and can be used in place of diagnostic peritoneal lavage as the initial indicator of significant intraperitoneal injury requiring surgical intervention.

Abdominal Injuries↗
PubMed1996

Pseudoatrophic macules: a variant of neurofibroma.

A 19-year-old man with neurofibromatosis type 1 showed a cutaneous plaque on the right scapular area with grayish coloration and atrophic appearance. Histopathologic examination demonstrated features of neurofibroma. Dermatologists should be aware of this uncommon clinical variant of neurofibroma in order to diagnose neurofibromatosis.

Adult↗
PubMed1996

Parastomal hernia.

Parastomal herniation is a common complication after stoma formation. The incidence can be reduced by using an extraperitoneal technique, limiting the size of the trephine to 1.5-2.0 cm or by strengthening with a mesh. If an intraperitoneal technique is used the intestine should be brought out through the rectus muscle. Generally, the symptoms are easily controlled with a support belt. Various techniques have been advocated for surgical repair. Fascial repair alone should no longer be performed owing to an unacceptably high recurrence rate, but should be combined with a prosthetic mesh. Relocation of the stoma should be performed for primary repairs.

Enterostomy↗
PubMed1996

The measurement of childhood trauma among male and female soldiers in the U.S. Army.

One thousand three hundred sixty-five soldiers from the U.S. Army completed a 30-item version of the Childhood Trauma Questionnaire (CTQ) together with four questions on sexual abuse developed for a national survey of U.S. adults. A four-factor solution to the CTQ produced four subscales that were similar to those found in the original study, namely (1) emotional neglect, (2) physical and emotional abuse, (3) sexual abuse, and (4) physical neglect. We found that half of female soldiers reported a childhood history of sexual abuse, compared with one-sixth of male soldiers. Half of both male and female soldiers reported a childhood history of physical abuse. Combined abuse histories were noted in 34% of female and 11% of male soldiers. Abused soldiers reported more psychological symptoms on the Brief Symptom Inventory than nonabused soldiers. The CTQ and screening questions are discussed as possible tools for eliciting histories of abuse from soldiers.

Adult↗
PubMed1996

An exercise program in the treatment of fibromyalgia.

OBJECTIVE: To assess the utility of an exercise program, which included aerobic, flexibility and strengthening elements, in the treatment of fibromyalgia (FM). FM is a chronic musculoskeletal condition characterized by diffuse musculoskeletal pain and aching. It has been suggested that aerobic exercise is helpful in its treatment. METHODS: We studied 60 patients who met American College of Rheumatology criteria for FM and had no significant comorbidities. Measurements performed on each patient at the pre and poststudy assessment included the number of tender points (TP), total myalgic scores (TM), aerobic fitness (AF), flexibility and isokinetic strength. After initial evaluation patients were randomly assigned to either an exercise or a relaxation group. Each group met 3 times per week for 6 weeks for 1 h of supervised exercise or relaxation. All patients data were stored in a computerized database and statistical analysis was performed on all pre and poststudy assessments. RESULTS: Thirty-eight patients (18 exercise and 20 relaxation) completed the study. Analysis of our data showed no significant difference between the groups in their prestudy assessment. Poststudy assessments, however, showed a significant improvement between the exercise and relaxation groups in TP (p < 0.05), TM (p < 0.05), and AF (p < 0.05). Similar improvements were also found when the pre and poststudy assessment of the exercise group were compared. CONCLUSION: Exercise is helpful in the management of FM in the short term. It also shows that FM patients can undertake an exercise program which includes aerobic, flexibility, and strength training exercises without adverse effects. The long term utility of this type of exercise requires further evaluation.

Adult↗
PubMed1996

Evaluation of minor penetrating duodenal injuries.

Penetrating duodenal injuries can present a confusing picture for the surgeon. A variety of treatment modalities exist including primary repair alone, primary repair with pyloric exclusion, duodenal resection, duodenal diverticulization, and the Whipple procedure. We reviewed 40 consecutive penetrating duodenal injuries in order to determine factors that led to complications of duodenal injuries, and to determine the most appropriate way to treat these injuries. Fourteen patients had combined pancreaticoduodenal injuries, five of whom developed pancreatitis. None of the patients without a combined pancreaticoduodenal injury developed pancreatitis (P < 0.05). Sixteen patients with minor duodenal injuries were treated by primary repair alone. In this group, five had combined pancreaticoduodenal injuries. Two of these five patients developed a suture line dehiscence and leak (P < 0.05). None of the 11 patients without a combined pancreaticoduodenal injury that were treated by primary repair alone developed a leak. Three patients with combined intermediate pancreaticoduodenal injuries were treated by primary repair with pyloric exclusion. None of these three patients developed a suture line dehiscence or leak. We conclude that combined pancreaticoduodenal injuries are more likely to develop pancreatitis, and that minor or intermediate combined pancreaticoduodenal injuries are more likely to develop a suture line dehiscence and leak. We recommend that the treatment of duodenal injuries be based on severity, location, and the presence of associated injuries. Minor injuries can be treated by primary repair alone, adding pyloric exclusion if there is a concomitant pancreatic injury.

Adolescent↗
PubMed1996

Childhood antecedents of psychological adaptation to military life.

This study examined the impact of a history of childhood abuse and neglect on soldiers' adaptation to Army life including commitment to the Army, confidence in leaders, and perceptions of unit cohesion and readiness. Childhood abuse and neglect were measured by the 30-item Childhood Trauma Questionnaire (CTQ) which comprises four subscales-sexual abuse, physical-emotional abuse, emotional neglect, and physical neglect. Information was obtained through a survey of 1,051 male soldiers and 305 female soldiers from combat support and combat service support units located at three different Army posts in the United States. The study found that of the four CTQ subscales, emotional neglect was the only variable predicting lower unit cohesion and lower confidence in leaders for both male and female soldiers even after controlling for concurrent psychological symptoms and sociodemographic variables. Emotional neglect during childhood may have a negative impact on soldiers' ability to access social support within their units, a factor that has been shown to prevent psychological breakdown in combat.

Analysis of Variance↗
PubMed1995

Association between tumour angiogenesis and tumour cell shedding into effluent venous blood during breast cancer surgery.

Tumour angiogenesis is a powerful prognostic indicator in breast cancer. Shedding of tumour cells into the bloodstream is essential for haematogenous metastasis. The relation between cell shedding and angiogenesis in human cancer is not known. We studied vascular density and cell shedding in 16 women undergoing breast cancer surgery. Circulating cells were found in one patient before, in six during, and none after operation. Vascular density was related to detection of circulating tumour cells during surgery (correlation coefficient for first intraoperative sampling = 0.56, p = 0.024, 95% CI 0.08 to 0.83). Tumour cell shedding during surgery is related to vascular density; the relevance of this relation to the prognostic significance of vascular density in breast cancer merits further study.

Breast Neoplasms↗