Constitutive expression and structural diversity of inducible isoform of nitric oxide synthase in human tissues

Nitric oxide (NO) produced by inducible nitric oxide synthase (iNOS) plays a major role in immune responses to bacteria and tumors, and the gene is induced by endotoxin and cytokines. However, we have detected iNOS cDNA sequences expressed constitutively at low level from human retinal, cerebellar and skeletal muscle tissues using northern-blot and RT-PCR analyses. In northern-blot analysis, two types (4.5 kb and 4.2 kb) of iNOS mRNA have been observed in retinal tissue, whereas only one type of mRNA was observed in cerebellum (4.5 kb) and skeletal muscle (4.2 kb). This result indicates that the presence of differential expression and/or structural diversity of the iNOS gene in various tissues, and some cells can express iNOS gene constitutively. We have also demonstrated a structural diversity formed by alternative splicing in the open reading frame sequence of the iNOS cDNA cloned from retinal tissue, which may reflect functional differences of iNOS gene.

Ifosfamide treatment of recurrent or metastatic endometrial stromal sarcomas previously unexposed to chemotherapy: a study of the Gynecologic Oncology Group

OBJECTIVE

To determine the effectiveness and toxicity of ifosfamide chemotherapy in women with metastatic or recurrent endometrial stromal sarcomas unexposed to other chemotherapy.

METHODS

In a prospective, multi-institutional phase II study conducted by the Gynecology Oncology Group, the starting dose of ifosfamide was 1.5 g/m2 given daily intravenously (i.v.) for 5 days (reduced to 1.2 g/m2 daily in patients who had previously received radiotherapy). Mesna (2 mercaptoethane sodium sulfonate) was given i.v. immediately and at 4 and 8 hours after the administration of ifosfamide. Each dose of mesna was 20% of the total daily dose of ifosfamide. Patients were treated every 3 weeks if blood counts permitted. Therapy was discontinued if there was progression of the cancer or unacceptable toxicity.

RESULTS

Twenty-two patients were entered into this study. One was excluded from analysis because of the wrong histologic type, leaving 21 evaluable for response and toxicity. Gynecologic Oncology Group grade 3 or 4 granulocytopenia occurred in four patients (19%), and one patient each experienced Gynecologic Oncology Group grade 4 anemia and genitourinary toxicity. Three patients experienced complete tumor responses and four had partial responses, for an overall response rate of 33.3%.

CONCLUSION

Ifosfamide is active in the therapy of women with chemotherapy-naive metastatic or recurrent endometrial stromal sarcomas.

Percutaneous balloon aortic valvuloplasty in high-risk elderly patients

From 1987 to mid-1994 we performed 16 percutaneous balloon aortic valvuloplasties. All patients (mean age 80 years; 53% female, 47% male) had significant congestive heart failure from aortic valve stenosis; the majority were categorized as New York Heart Association Class IV (shortness of breath at rest). Twelve patients were not surgical candidates; four patients refused surgery. After valvuloplasty, all patients became asymptomatic (NYHA Class I & II), the average preprocedure valvular gradient of 59 mm Hg decreased to 31 mm Hg, and valve area increased from 0.8 cm2 (0.3 cm2-0.98 cm2) to 1.3 cm2 (0.6 cm2-1.44 cm2). The only complications were two minor groin hematomas (2 patients). Within 6 months, 50% of the patients were symptomatic again; the overall survival rate was 23 months. We conclude that in the proper environment this procedure can be effective and safe--even in high-risk elderly patients. Although symptom improvement is transient, valvuloplasty provides a valuable opportunity to treat intercurrent medical conditions and possibly follow up with surgery.

Mortality at an automotive stamping and assembly complex

Mortality among workers with 2 or more years employment at an automotive stamping and assembly complex was analyzed using standardized mortality ratio (SMR), proportional mortality ratio (PMR), and mortality odds ratio (MOR) methods. The stamping plant all-cause SMR was considerably less than expected (for white men, SMR = 0.65, 95% confidence interval [CI] = 0.54, 0.79; for black men, SMR = 0.73, 95% CI = 0.45, 1.13), indicating a strong "healthy worker effect." However, six stomach cancer deaths produced an SMR of 4.4 (95% CI = 1.62, 9.6) and a PMR of 6.8 (95% CI = 2.5, 15). Based on small numbers of cases, stomach cancer risk increased with duration in stamping and tool and die departments where exposures included drawing compound and other metalworking fluids. Stamping plant lung cancer mortality was elevated among production welders (MOR = 2.7, 95% CI = 1.2, 6.3), and increased with duration. Welding was performed on sheet metal sometimes coated with drawing compound, primer, or epoxy resin adhesive. As was observed for the stamping plant, the all-cause SMR for the two assembly plants was unusually low (for white men, SMR = 0.64, 95% CI = 0.56, 0.73; for black men, SMR = 0.57, 95% CI = 0.43, 0.75). The lung cancer SMR was not elevated but the MOR was (MOR = 1.58, 95% CI = 1.1, 2.4) and increased with assembly plant duration (MOR = 1.78, 95% CI = 1.02, 3.1, at mean duration of cases). In the assembly plants, paint oven stack emissions had been reintroduced into the plant by the ventilation system.

Excitatory and inhibitory effects of serotonin on spinal axons

We studied the effects of serotonin on compound action potentials in dorsal columns isolated from young (nine to 13 days old) rats. Conducting action potentials were activated by submaximal (50%) and supramaximal constant current electrical stimuli and recorded with glass micropipettes. At 10 microM and 100 microM concentrations, serotonin significantly increased mean action potential amplitudes by 9.6 +/- 6.5% (+/- S.D., P < 0.05) and 16.6 +/- 12.2% (+/- S.D., P < 0.005), respectively. Likewise, 10 microM and 100 microM of quipazine (a serotonin2A agonist) increased the amplitudes by 9.6 +/- 2.5% (+/- S.D., P < 0.0005) and 37.7 +/- 8.7% (+/- S.D., P < 0.0005), respectively. In contrast, 10 microM and 100 microM concentrations of 8-hydroxy-dipropylaminotetralin-hydrobromide (a serotonin 1A agonist) reduced axonal excitability by -9.4 +/- 5.5% (+/- S.D., P < 0.05) and -32.9 +/- 10.6% (+/- S.D., P < 0.0005), respectively. At 50 microM concentration, mianserin (a serotonin2A and serotonin2C antagonist) eliminated the excitatory effects of 100 microM quipazine dimaleate. The combination of 50 microM mianserin and 100 microM serotonin reduced action potential amplitudes by -5.6 +/- 4.9% (+/- S.D., P < 0.05). These results suggest that serotonin1A and serotonin2A receptor subtypes are present on spinal dorsal column axons. These two receptor subtypes have opposing effects on axonal excitability. The ratios and sensitivities of these two axonal receptor subtypes may modulate axonal excitability in rat dorsal column axons and have important implications for both development and injury of axons.

A dominant Stargardt's macular dystrophy locus maps to chromosome 13q34

OBJECTIVE

To identify the chromosomal location of a mutated gene that causes an autosomal dominant Stargardt's macular dystrophy.

METHODS

Ocular examinations were performed on 67 members of a large kindred to identify those with macular dystrophy. DNA analyses defined the genotype of all family members at 49 polymorphic loci. Linkage between the gene defect responsible for this macular dystrophy and each polymorphic locus was assessed by lodscore calculations.

RESULTS

Diminished visual acuity and funduscopic abnormalities were found in 29 family members, which was diagnostic of macular dystrophy. Genetic analyses demonstrated that polymorphic loci from chromosome 13 band q34 were linked to the gene defect in this family. Haplotype analyses localized the disease locus to an 8-centimorgan interval between loci D13S159 and D13S158/D13S174.

CONCLUSION

A disease locus responsible for an autosomal dominant Stargardt's macular dystrophy is located on chromosome 13 band q34. Identification of the mutated gene at this locus will lead to a better understanding of macular degeneration.

Clinical stage IB endometrial adenocarcinoma with an isolated small bowel metastasis

Although patients with widely disseminated endometrial adenocarcinoma can have tumor involving the intestine, a focal metastasis to the small bowel with no other evidence of extra-uterine spread has not been reported. A patient with a clinical stage IB, grade 2 superficially invasive endometrial adenocarcinoma was found to have an isolated distant metastasis to the small intestine. The patient has been asymptomatic and disease free for almost 4 years following postoperative treatment with whole abdominal radiation therapy on a Gynecologic Oncology Group protocol. The finding of a solitary small bowel metastasis was not predictable based on the current understanding of the biologic behavior of endometrial adenocarcinomas. This case emphasizes the need for a thorough abdominal exploration in patients with endometrial adenocarcinoma by surgeons trained to detect and resect abdominopelvic tumors, and it validates the need for innovative treatment protocols for women with gynecologic malignancies.

Management of advanced ovarian epithelial cancer in the renal transplant patient

Stage IIIC, grade 1 papillary serous adenocarcinoma of the ovary was diagnosed in a 28-year-old renal transplant recipient. She had been treated with the immunosuppressive agents azathioprine and methylprednisolone for 7 years prior to the discovery of the ovarian cancer. Surgical excision of the tumor was suboptimal due to involvement of the allograft; however, the patient achieved a complete clinical response after eight courses of cisplatin and cyclophosphamide. Since multiagent immunosuppressant therapy may have contributed to the development of the ovarian carcinoma, the intensity of immunosuppression was decreased by discontinuing the azathioprine as soon as the diagnosis of ovarian cancer was made. The methylprednisolone, however, was continued to decrease the possibility of organ rejection. After completion of chemotherapy, the patient was started on a daily regimen of low-dose oral cyclophosphamide as an immunosuppressant. Four months following the completion of cytotoxic therapy, she developed clinically evident disease in the pelvis. Subsequent salvage therapy with carboplatin failed. The patient died from progressive disease 26 months after initial diagnosis. She never developed evidence of renal rejection. Combined modality cancer therapy, preservation of allograft function, and modification of immunosuppressant therapy are important goals in the renal transplant patient with advanced ovarian carcinoma.

Etiology of the sexual dimorphism in renal peripheral benzodiazepine receptor response to stress in rats

A sexual dimorphism in stress-induced alterations in renal peripheral benzodiazepine receptors (PBR) was recently reported. The present paper includes five experiments examining the etiology of this sex difference. Surgical removal of ovaries and testes was ineffective in altering the renal PBR stress response in both male and female rats. A diurnal variation in the sexual dimorphism was observed; the difference was seen in the early part of the light cycle, while the two sexes were indistinguishable at the end of the light cycle. Finally, based on recent data indicating the importance of the renin-angiotensin system in the stress-induced decrease in renal PBR, we examined both stress-induced plasma renin activity and renal PBR reactivity to exogenous angiotensin II (AII) administration in both sexes. Female rats show both an attenuated elevation of plasma renin levels in response to inescapable shock stress and a reduced PBR response to AII administration in comparison to males. The present data indicate that the renin-angiotensin system may be a critical factor in the sexual dimorphism in the renal PBR response to stress. The possibility of this difference in the renin-angiotensin system contributing to sex differences in susceptibility to escape deficits following inescapable shock is entertained. The implications for these findings regarding the physiological function of the PBR are also discussed.

Ovarian management during radical hysterectomy in the premenopausal patient

OBJECTIVE

To determine whether the ovaries should be retained or removed in premenopausal women undergoing radical hysterectomies for cervical carcinoma.

METHODS

Questionnaires were sent to all women who had radical hysterectomies without further therapy for cervical carcinoma at our institution over a 16-year period. Those who had retained ovarian tissue were asked to have serum gonadotropin levels measured.

RESULTS

Eighty-four of 124 eligible women (68%) responded. Sixty-eight respondents were premenopausal at the time of surgery. Thirty-eight had a bilateral salpingo-oophorectomy (BSO), 20 had one ovary preserved, and ten retained both ovaries. Six of 30 (20%) who retained ovaries developed early hormonal failure. Two of these 30 (7%) required oophorectomies subsequently. Twenty-seven of 38 BSO patients (71%) were compliant with their hormone replacement regimens. Fourteen of 15 women (93%) age 40 or younger were compliant, whereas 13 of 23 (57%) over age 40 were compliant (P < .05). Twenty-three of 34 BSO respondents (68%) reported improved or unchanged sexual relations, compared with 24 of 27 (89%) who retained ovaries (P > .05).

CONCLUSIONS

Twenty-seven percent of our premenopausal women with retained ovaries have experienced early loss of hormonal function or required subsequent oophorectomies. For an accurate estimate of ovarian longevity, all patients would have to be followed through menopause. Compliance in taking hormone medication was high in our young patients. Sexual function was not adversely affected following castration. A hypothetical cost comparison favored removing, rather than retaining, the ovaries. We recommend that elective BSO be performed on most premenopausal women undergoing radical hysterectomies for cervical carcinoma.

Intestinal invasion by a dysgerminoma in a patient with Swyer syndrome

An unusual case is presented of advanced dysgerminoma in a patient with Swyer syndrome, 46,XY pure gonadal dysgenesis. Unexpected regional invasion necessitated bowel resection, total abdominal hysterectomy, and bilateral salpingogonadectomy for a complete en bloc excision of the primary tumor mass and the dysgenetic gonads. This report illustrates the possible need for extensive operative resection in patients with Swyer syndrome.

Clinical surveillance of gynecologic cancer patients

A survey of gynecologic oncologists was used to determine the optimum follow-up plan for asymptomatic, disease-free patients previously treated for a gynecologic malignancy. Ninety-four (91%) of 103 questionnaires were completed and returned. The majority of respondents recommended a clinic visit for these patients every 3 months for the first year after the completion of therapy, every 3 or 4 months for the second year, every 6 months for the following 3 years, and then annually after this initial 5-year period. Breast, abdominal, lymph node, and pelvic examinations, as well as a pap smear and stool guaiac, were done at each of these clinic visits. A yearly chest X ray was performed by the majority of the survey respondents for the first 3 years following initial treatment. Determinations of serum CA-125 and ovarian germ cell tumor markers were done at each follow-up appointment during the first 5 years after therapy if they were previously elevated. The patients' smoking habits were discussed with them by the majority of respondents. Mammograms were performed periodically before age 50 and then yearly after age 50 by most respondents. Serum cholesterol determinations were accomplished every 5 years or more frequently if indicated. Calcium supplementation was recommended for postmenopausal patients. The majority of respondents did not recommend routine vitamin supplementation or surveillance sigmoidoscopy.

Stress resistance of Drosophila transgenic for bovine CuZn superoxide dismutase

Several oxidative and non-oxidative stresses were applied to two transgenic strains of Drosophila melanogaster (designated P(bSOD)5 and P(bSOD)11) that express superoxide dismutase (SOD) at elevated levels, and control strains that express normal SOD levels. Transgenic strain P(bSOD)5 exposed to paraquat (1,1'-dimethyl-4,4'-bipyridinium dichloride), a redox cycling agent that generates superoxide anion when metabolized in vivo, was significantly more resistant to this xenobiotic than control flies. When test flies were subjected to 100% oxygen for 20 min each day, the mean lifespan was 3.62 days for control strain 25, but 4.35 days for both transgenic strains. The mortality curves of strains fed 1% H2O2 were similar, but the median lifespan of 72 h for controls and 64 h for transgenics suggests that the transgenic flies were slightly more sensitive to H2O2. The activity of catalase was the same for all strains. Using starvation resistance as a non-oxidative stress, flies maintained on water without any food had identical survival curves; for all strains, the median lifespan was 72 h. Throughout the lifespan, no statistically significant difference in physical activity was displayed for transgenic versus control flies. Collectively, these data suggest that the increased lifespan previously observed in SOD transgenics is specifically related to resistance to oxidative stresses.

Nongenital pelvic leiomyosarcoma metastatic to the heart

A patient who had a 5-year history of a low-grade nongenital pelvic leiomyosarcoma was evaluated for worsening dyspnea, hypertension, and jugular venous distension. An echocardiogram revealed a large right atrial mass. At surgical exploration, metastatic leiomyosarcoma was found within the inferior vena cava extending from below the renal veins up into the right atrium. Using cardiopulmonary bypass with profound hypothermia and circulatory arrest, the inferior vena cava was opened below the renal veins, and the tumor was transected. That portion of the tumor above this transection was then extracted through a right atriotomy. Resection of the pelvic tumor was not thought to be feasible. The patient remains asymptomatic with stable pelvic tumor 1 year after the procedure.

A technique for managing terminally ill ovarian carcinoma patients

A patient with terminal ovarian carcinoma was admitted with malnutrition, abdominopelvic pain, and an inoperable complete small bowel obstruction after failing standard therapy and several experimental regimens for her disease. Despite this serious situation, she had an overall high performance status. Instead of administering intravenous narcotics, providing nasogastric suction, and giving other supportive care to make her apparently imminent death as comfortable as possible, her malnutrition was treated with total parenteral nutrition administered through an indwelling central venous catheter during the night hours only. The pain was successfully treated with an indwelling epidural catheter with the continuous infusion of morphine through a portable pump carried by a shoulder strap. The intestinal obstruction was relieved by a percutaneous endogastric tube which drained spontaneously into a leg bag. This regimen allowed the patient complete daytime mobility. She remained active, largely at home, with slowly progressing tumor until her death 9 months after the institution of this supportive care.

Radical vulvectomy with partial rectal resection and temporary colostomy as primary therapy for selected patients with vulvar carcinoma

The patient with carcinoma of the vulva may present with tumor involvement of the perirectal area. Traditional treatment has often involved ultraradical therapy including a radical vulvectomy with posterior or total pelvic exenteration in an effort to obtain adequate surgical margins. Five-year survival rates for these patients range from 20-50%, and major operative morbidity as well as psychological problems are associated with this extensive surgery. Five patients treated for a locally advanced vulvar carcinoma involving the perirectal area were thought to be candidates for a rectum-sparing procedure. They underwent a radical vulvectomy, bilateral inguinal lymphadenectomy, partial rectal resection, and a diverting colostomy. Four of the five patients agreed to a colostomy closure 6 months after their primary therapy; these four patients have resumed normal bowel function. All patients remain clinically free of tumor.

Indwelling epidural catheters for pain control in gynecologic cancer patients

Seven patients with severe pain caused by an advanced, incurable gynecologic malignancy were treated with an indwelling epidural catheter connected to an implantable subcutaneous port through which morphine was infused. There were few major complications associated with insertion or maintenance of the system. The average usage was 60 days, although the system functioned continuously for 6 months in one patient. Pain distribution in these women ranged from the upper abdomen to the lower extremities. All patients, including one with liver metastases, reported good to excellent pain control with the epidural narcotics. Two subjects with upper abdominal pain occasionally required supplemental oral oxycodone, but the other five patients had adequate pain relief with the epidural system alone. The indwelling epidural system provides excellent analgesia for patients with advanced, incurable gynecologic cancer.

Osseous metaplasia in ovarian papillary serous cystadenocarcinoma

The finding of osseous metaplasia within an ovarian papillary serous cystadenocarcinoma is very rare. A review of the medical literature reveals only two previously published cases where mature bone was found in an ovarian serous cystadenocarcinoma. This report presents an additional case of this unusual phenomenon whose clinical significance remains uncertain.

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Long sentences, medical terms and small print make hospital information brochures and consent forms difficult for many patients to understand. There are, however, things nurses can do to make written information for patients more accessible.