Intermediates and products of the reaction of Zn(ii) organyls with tetrel element Zintl ions: cluster extension versus complexation.

The discovery of low-valent Zn compounds resulted in the renaissance of organometallic Zn complexes. Polyhedral clusters of tetrel elements can interact with Zn atoms either as Lewis donors or by incorporation of the Zn atoms as additional cluster vertices. Herein we report the reactions of ZnR2 (R = ethyl (Et), pentamethylcyclopentadiene (Cp*), phenyl (Ph) and 1,3,5-trimethylbenzene (Mes)) with Zintl ions of the types [E4]4- (E = Ge, Sn) and [Ge9]4- in liquid ammonia. Besides the desired Zintl ion complexes, intermediates were isolated that give insight into the reaction of organo Zn compounds in liquid ammonia. Three ions, [(η3:η3-Ge4)(ZnEt)2]2- (1a), [(η2-Sn4)Zn(η2-Sn4)]6- (2a) and [(η4-Ge9)(ZnEt)]3- (3a), were obtained and characterized by means of single crystal X-ray diffraction analysis. Furthermore, amides [(ZnPh2)2(µ2-NH2)2]2- (4a) and {[Zn(µ2-NH2)4][(ZnEt)2(µ2-NH2)2]2}2- (5a) were formed during the reactions, together with the addition products [ZnPh3]- (6a) and [ZnMes3]- (7a) and an anion [Cp*]- (8a), suggesting the following reaction sequence: in liquid ammonia the Zintl anions form amides, which then serve as ligands for ZnR2 molecules. The NH2- ligands weaken the corresponding Zn-R bonds, and thus bond cleavage and the addition of the Zintl anion to the Zn ion can take place, additionally promoted by the trapping of the leaving group R- by unreacted Zn organyls with the formation of [ZnR3]-.

Electrochemical therapy of pelvic pain: effects of pulsed electromagnetic fields (PEMF) on tissue trauma.

Unusually effective and long-lasting relief of pelvic pain of gynaecological origin has been obtained consistently by short exposures of affected areas to the application of a magnetic induction device producing short, sharp, magnetic-field pulses of a minimal amplitude to initiate the electrochemical phenomenon of electroporation within a 25 cm2 focal area. Treatments are short, fasting-acting, economical and in many instances have obviated surgery. This report describes typical cases such as dysmenorrhoea, endometriosis, ruptured ovarian cyst, acute lower urinary tract infection, post-operative haematoma, and persistent dyspareunia in which pulsed magnetic field treatment has not, in most cases, been supplemented by analgesic medication. Of 17 female patients presenting with a total of 20 episodes of pelvic pain, of which 11 episodes were acute, seven chronic and two acute as well as chronic, 16 patients representing 18 episodes (90%) experienced marked, even dramatic relief, while two patients representing two episodes reported less than complete pain relief.

Gastrointestinal cancer in the elderly.

The older patient population, aged 70 years and greater, represent a large proportion of patients diagnosed with gastrointestinal malignancies. Surgery remains the mainstay of treatment for these malignancy sites. Chronologic age alone should not determine the extent of surgical or medical management. The authors describe those aspects of gastrointestinal cancer detection and therapy that are unique to the aging population.

Skin-level gastrostomies and jejunostomies for long-term enteral feeding.

Skin level gastrostomies and jejunostomies were used in 17 patients for long-term enteral feeding. These devices offer greater comfort to the patient and less potential complications and dysfunction compared to tube gastrostomies and jejunostomies. Placement of the skin level devices requires "mature" gastrocutaneous and jejunocutaneous fistulas. These fistulas can be created by initial placement of percutaneous endoscopic gastrostomies and jejunostomies.

Locally advanced breast carcinoma: results with combined regional therapy.

To define optimal regional treatment as initial management of locally advanced (Stage III & IV) breast cancer, 509 patients treated from 1966-1982 were reviewed. All patients received comprehensive postoperative irradiation of the peripheral lymphatics and chest wall, following surgical procedures varying from incisional biopsy to classical radical mastectomy. Patients were followed from 1 to over 16 years. The survival rate at 5 and 10 years for the entire series is 41% and 26%. Fifty-eight patients having radical surgery for T3 tumors and subsequently found to have negative axillary lymph nodes showed the highest rates of survival, 72% at 5 years and 57% at 10 years. This was significantly better (p less than .01) than patients with T3N+ disease, (5 year survival 44%; 10 year, 29%) and T4N+ disease (44%, 39%). Four hundred seventy patients with non-inflammatory carcinoma and no supraclavicular metastases were considered technically resectable. Three hundred eighty-one of these patients underwent a definitive surgical procedure removing all gross cancer prior to irradiation and, as expected, showed higher rates of local disease control than patients having lesser surgery (79% versus 45%, p less than .01). These patients also showed markedly better rates of survival and relapse-free survival with 50% alive and 38% disease free, versus 14 and 8%, at 5 years (p less than .01). There were no 10 year survivors among the 89 technically resectable patients having less than total gross resection. Long term relapse-free survival of locally advanced breast cancer can be achieved with aggressive combined local-regional therapy. Total resection of all gross cancer prior to irradiation is recommended. Modifications of postoperative radiation therapy techniques are suggested to further improve local control rates for these advanced tumors. This large series provides a baseline for evaluation of current programs adding adjuvant systemic therapy to regional treatment.

Myometrial penetration of endometrial carcinoma as a prognostic factor for patients receiving pre- or postoperative radiation therapy.

From 1966-1980, 227 patients with Stage I endometrial carcinoma were treated by total abdominal hysterectomy, bilateral salpingo-oophorectomy, and either pre- or postoperative external beam pelvic irradiation. All therapy was delivered with megavoltage equipment. There was at least a 4-week interval between irradiation and surgery for 164 patients treated preoperatively. No significant differences were found in subsequent survival or local control at 5 years for those patients left with no residual tumor (81% survival/97% local control), disease confined to the mucosa (83% survival/93% local control), or invasion of the inner half of the myometrium (81% survival/93% local control). However, patients left with deeper myometrial penetration showed a significantly poorer survival rate of 57% (p = 0.02) and a local control rate of only 65% (p = 0.006). For 63 patients treated postoperatively, there was no significant difference in 5-year survival or local control for those patients with disease limited to the inner 1/2 of the myometrium (80% survival/93% local control) compared with more extensive myometrial invasion (75% survival/86% local control). As patients with deep myometrial penetration irradiated postoperatively showed survival rates comparable to patients with lesser extent of invasion, the adverse prognostic effect of deep penetration appears to have been attenuated by subsequent pelvic irradiation. By contrast, residual deep myometrial invasion remained a significant adverse prognostic indicator for patients treated preoperatively. For this group, further treatment seems necessary and postoperative vaginal brachytherapy and/or adjuvant chemotherapy should be considered.

The significance of local recurrence of carcinoma of the breast.

One hundred twenty-one patients with local or regional recurrence of carcinoma of the breast without evidence of distant metastases were treated with megavoltage radiation therapy. All patients had radical or modified radical mastectomy as their initial treatment. The 10 year survival probability of this group of patients is 26%, with a local control probability of 46%. Within this group of patients with recurrent disease, factors found to be associated with a poorer prognosis include peripheral nodal recurrence, advanced initial disease stage and short disease free interval. Contrary to expectation, patients with recurrence within the mastectomy scar (as opposed to chest wall recurrence wide of the scar) or a history of previous radiotherapy had poorer local control rates (although not statistically significant), without effect upon overall survival. Comprehensive radiation therapy (peripheral lymphatic plus chest wall) enhanced the local control rate for the entire group and the survival probability for patients with isolated chest wall recurrence compared with limited radiation therapy fields. (Five year survival probability: chest wall irradiation only = 27%; chest wall and peripheral lymphatic = 54%). Patients given systemic therapy at the time of local recurrence showed no survival benefit. Aggressive, comprehensive radiation therapy is indicated for locally recurrent breast cancer. More effective systemic therapy is needed, especially for higher risk patients.

Exposure duration as a confounding methodological factor in projective testing.

Exposure duration has been found to have a strong impact on the affective value attributed to a variety of stimuli. The purpose of the study reported here was to examine the impact of this variable in projective testing, and im particular in the affective value subjects attribute to the TAT cards. Using 34 undergraduate students, a linear decrease in pleasantness was found as a function of exposure duration. Factors leading to variation in exposure duration might therefore be confounded with the interpretations made of a subject's protocol. It was suggested that the time a subject views a projective test stimulus should be controlled in the administration.