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Objective: Our objective was to elucidate the pathophysiologic effects and potential reversibility of terbutaline-induced changes in carbohydrate metabolism., Study Design: We prospectively evaluated serum glucose, insulin, glucagon, C-peptide, and pancreatic polypeptide levels in response to a 100 gm glucose challenge (oral 3-hour glucose tolerance test) in 17 obstetric patients without complications who were given terbutaline (5 mg orally every 4 hours) for 5 consecutive days between 24 and 32 weeks' gestation. Each patient served as her own control, with day 1 representing pretreatment, day 7 the treatment phase, and day 14 the posttreatment evaluation. Body mass index and posttreatment serum terbutaline levels were also measured., Results: A significant initial treatment effect (day 1 versus 7) was observed for glucose (elevated), insulin (elevated), insulin/glucose ratio (elevated), and pancreatic polypeptide (elevated). A significant delayed treatment effect (day 1 versus 14) was also observed for insulin (elevated), insulin/glucose ratio (elevated), and pancreatic polypeptide (elevated). Body mass index directly correlated with postchallenge measures of insulin, insulin/glucose ratio, pancreatic polypeptide, and C-peptide. Posttreatment serum terbutaline levels directly correlated with pancreatic polypeptide, but not with other parameters., Conclusions: Our data support a dose-independent, terbutaline-induced glucose intolerance mediated by glucagon and caused by diminished insulin sensitivity.

From Jan 1, 1983 to April 30, 1989, 32 patients underwent 38 endobronchial treatments with 192Ir, bronchoscopically inserted for treatment of endobronchial obstructions secondary to bronchogenic carcinoma. Thirty-four of the 38 treatments were far enough apart to allow separate response analysis. Thirty of the 34 patients were symptomatically improved or stable; 22 of 24 patients who could be evaluated roentgenographically showed improved or stable chest roentgenograms, and ten of 12 patients evaluated bronchoscopically demonstrated improved patency of bronchial lumen.

Twenty patients (aged 50 +/- 21 years and mean left ventricular ejection fraction 37 +/- 17%) with recurrent ventricular arrhythmias were treated with an investigational, implantable combined antitachycardia-pacing cardioverter defibrillator. The device's telemetry capabilities include both stored (1-second snapshots) and real-time display of endocardial and device-circuit signals. The device can store these before, during and after up to 50 tachycardia and antitachycardia pacing episodes. All stored events are indexed to a 24-hour internal clock. During 10.1 +/- 5.1 months of follow-up, the device was used in 11 of 20 patients. In the entire group, antitachycardia pacing was activated on 44 +/- 14 occasions per patient (total 874) and shock delivery occurred on 8 +/- 14 occasions per patient (total 156). Reconstruction by stored telemetry of all device-therapy episodes was possible. Twenty-six percent of all shocks delivered were not appropriate and were due to atrial arrhythmias in 2 patients and dysfunction of the sensing lead in 3. The absence of a relation between symptoms and appropriate shock delivery was documented in 1 patient. Antitachycardia pace acceleration occurred in 5.3% of cases; 7% of attempts at pacing were unsuccessful and needed shock therapy. It is concluded that the enhanced telemetry available in newer antitachycardia devices enables more accurate assessment of device use and enhances diagnosis of inappropriate therapy delivery.

Vasodepressor reactions were induced in 27 rats by a combination of inferior vena caval occlusion and an infusion of isoproterenol. A vasodepressor reaction was defined as paradoxical heart rate slowing during inferior vena caval occlusion. The R-R intervals were measured at 5-s intervals before, during, and after 60 s of inferior vena caval occlusion. The purpose of this study was to examine the role of the right and left vagus nerve and the right and left stellate ganglia in this reflex. Under control conditions inferior vena caval occlusion accelerated the rate (R-R, -15.9 +/- 0.9 ms). During an infusion of isoproterenol (0.5-1.0 micrograms.min-1), inferior vena caval occlusion produced paradoxical rate slowing, i.e., a vasodepressor reaction (R-R, +75.0 +/- 2.2 ms). The vasodepressor reaction was examined during inferior vena caval occlusion and isoproterenol under the following additional states: atropine methyl bromide or right vagotomy did not alter the reaction; left vagotomy eliminated the reaction; and right or left stellectomy greatly reduced the vasodepressor reaction. We conclude the following: (1) left vagal afferents mediate the vasodepressor reaction; (2) cardiac sympathetic fibers participate in the vasodepressor reaction by withdrawing efferent tone through the right stellate ganglion, and by generating the afferent signal, which triggers the vasodepressor reaction through the left stellate ganglion.

Ventricular tachycardia or ventricular fibrillation was electrically induced in 38 normal rats (group 1) and 24 sympathetically denervated rats (6-hydroxydopamine) (group 2). The time for spontaneous reversion to sinus rhythm was measured during (1) control, (2) isoproterenol, and (3) the combination of isoproterenol and phenylephrine. The time for spontaneous reversion was the same in both groups in the three states. The reversion time was prolonged threefold by isoproterenol, and restored to control values when phenylephrine was added to the infusion of isoproterenol. The tachycardia duration and the refractory period were inversely related: log10 (tachycardia duration) = 3.466-0.091 (refractory period). Ventricular tachycardia/fibrillation induction was examined as follows: (i) Ventricular tachycardia/fibrillation was induced in 100% of normal rats (group 1), but only 42% of the denervated rats (group 2, p less than 0.001); (ii) during isoproterenol, ventricular tachycardia/fibrillation was induced in 100% of rats of both groups; and (iii) when phenylephrine was added to isoproterenol, ventricular tachycardia/fibrillation was induced in 100% of group 1 rats versus 82% of group 2 rats, (p = NS). These observations suggest (1) the induction of ventricular tachycardia/fibrillation is highly dependent on intact sympathetic innervation, and (2) exogenous adrenergic agonists modulate the duration of ventricular fibrillation through their effects on ventricular refractory period, independent of sympathetic innervation.

Unlabelled: Testing for the susceptibility for vasodepressor reaction in humans involves the combination of restriction of venous return by passive upright tilting and the administration of isoproterenol. To explore the basis of the vasodepressor test in humans, the present experiment examined whether a reduced cardiac volume coupled with adrenergic stimulation causes a vasodepressor reaction in rats. Vasodepressor reaction was defined as paradoxical heart rate slowing in conjunction with hypotension during inferior vena caval occlusion. Inferior vena caval occlusion was performed for 60 s and the maximum changes in R-R were measured during seven states as follows. (A) Under control conditions inferior vena caval occlusion alone accelerated the rate in 32 of 32 rats (delta R-R, -13.9 +/- 1.7 ms, p less than 0.001). (B) When inferior vena caval occlusion was performed during an infusion of isoproterenol (0.5-1.0 micrograms.min-1), a vasodepressor reaction was observed in all rats as the heart rate slowed (delta R-R, +138.1 +/- 14.8 ms, p less than 0.001). The vasodepressor reaction was further examined during isoproterenol and inferior vena caval occlusion under five additional states. (C) After atropine the vasodepressor reaction was unchanged (delta R-R, +132.7 +/- 24.8 ms, p less than 0.001). (D) After bilateral vagotomy the paradoxical slowing was eliminated. (E) After intrapericardial lidocaine the paradoxic slowing was eliminated. (F) After bilateral stellectomy nonsignificant slowing was still present, but this was markedly reduced when compared with B (p less than 0.001). (G) Following chronic chemical sympathetic denervation with 6-hydroxydopamine the paradoxic bradycardia was eliminated., Conclusions: (1) Reduced cardiac volume combined with adrenergic stimulation can stimulate a vasodepressor reaction; (2) the vasodepressor reaction requires signalling by the afferent but not efferent vagal fibers; (3) the bradycardia is mainly due to withdrawal of sympathetic efferent tone.

Descriptive data are presented on the employment patterns of youths with mild disabilities who participated in a transition program with an intensive postsecondary component. Data on employment rates, positive and negative job changes, participation in continuing education, and access to benefit packages are reported for 94 youths who participated in the program over a 4-year period. Program participants had favorable outcomes when compared with a national sample, but they stabilized at an entry level of work participation. Their rates of entry into postsecondary education were also greater than the national sample, but advances were nominal.

The effects of passive upright tilting from 0 degrees to +60 degrees (n = 27), Valsalva maneuver (n = 16) and respiration (n = 10) on the rate of atrial flutter were studied in 27 patients. After tilting to +60 degrees, the atrial flutter cycle length shortened in all patients from 247.5 +/- 7 to 236.7 +/- 6.9 ms (range of shortening 1 to 21 ms, p less than 0.001). The Valsalva maneuver (strain of 40 mm Hg) shortened the flutter cycle length during the strain (phase 2) from 242.2 +/- 4.6 to 230.5 +/- 5 ms (range of shortening 2 to 19 ms, p less than 0.001). In 10 patients whose respiration was monitored, the flutter cycle length consistently prolonged during inspiration and shortened during expiration. Combined beta-adrenergic and muscarinic receptor blockade in six patients did not significantly alter the flutter cycle length at rest or the effects of the various maneuvers on the changes in flutter cycle length. This study revealed that the atrial flutter cycle length can be shortened by passive upright tilting, the strain phase of the Valsalva maneuver and expiration. Changes in flutter cycle length were independent of autonomic tone, implying that by decreasing cardiac volume, these maneuvers affect characteristics of the atrial flutter circuit, thereby producing dynamic changes in the rate of atrial flutter.

Objective: The purpose of our study was to examine the cardiopulmonary complications of a group of patients who had undergone implantation of adrenal medullary tissue into the caudate nucleus for treatment of neurologic disease., Design: Prospective study with partially matched historical controls., Setting: Tertiary care community medical center., Patients and Methods: Seven patients with advanced Parkinson's disease and three patients with progressive supranuclear palsy underwent implantation of adrenal medullary tissue into the caudate nucleus. These patients were compared with respect to their cardiopulmonary complications with a control group who had undergone craniotomy and then compared with a control group who had undergone only abdominal surgery., Results: In the study group, six patients developed major postoperative complications including development of large pleural effusions, lobar atelectasis, pneumonia, upper airway obstruction, and cardiac arrest. Three patients had minor complications including development of small pleural effusions, subsegmental atelectasis, purulent bronchitis, mild congestive heart failure, and atrial flutter/fibrillation. One patient had an unremarkable postoperative course. The first control group, whose only surgery was a craniotomy, had only one major complication. The second control group, the abdominal surgery control group, had one major and five minor complications., Conclusion: The particular neurologic disease, its severity, and the type of surgery performed appear to be causative factors in the high incidence of complications in the study group.

Human amnion cells synthesize and release prostaglandin E2 in response to epidermal growth factor. The protein kinase C activator, phorbol 12-myristate, 13-acetate also stimulates amnion cell prostaglandin E2 synthesis. We used a human amnion cell line (WISH) to conduct in vitro experiments to investigate a potential role of protein kinase C in the signal transduction pathway leading to epidermal growth factor-induced prostaglandin E2 production. Pretreatment of cultured amnion cells with a low, nonstimulating dose of phorbol 12-myristate, 13-acetate potentiated the action of epidermal growth factor in causing prostaglandin E2 production as measured by radioimmunoassay. The protein kinase C-selective inhibitor staurosporine inhibited epidermal growth factor-induced prostaglandin E2 production, further suggesting a role for protein kinase C in epidermal growth factor action. Experiments were conducted in which amnion cells were rendered protein kinase C-deficient by chronic exposure to phorbol ester, which has been shown to down-regulate the enzyme. In these cells, epidermal growth factor caused prostaglandin E2 synthesis at levels comparable to native (non-protein kinase C-deficient) cells. We conclude that protein kinase C plays a more modulatory than direct role in the epidermal growth factor signal transduction cascade that leads to prostaglandin E2 production by amnion cells. We propose a bifurcating transduction scheme in which, under conditions of protein kinase C inactivation, epidermal growth factor alone causes prostaglandin E2 synthesis. When protein kinase C is activated by as yet unknown endogenous substances, the epidermal growth factor responsiveness of the amnion cells is greatly enhanced. This pathway could have important implications in a feed-forward mechanism regulating the level of prostaglandin E2 production during the onset of labor.

Seven patients with Parkinson's disease and three patients with progressive supranuclear palsy underwent adrenal medullary transplant to the caudate nucleus for treatment of their neurologic disease. Preoperative nutritional assessment demonstrated that a significant number of the Parkinson's patients had mild to moderate nutritional depletion. Motility problems, manifest by dysphagia and delayed gastric emptying causing problems over a number of years, were probably responsible. Of the 10 patients studied, 6 were studied by videofluoroscopy. All patients had variable dysphagia of variable servility with or without aspiration. Etiologic factors included the basic underlying neurologic disease, delay in resumption of anti-parkinsonian medications, use of metoclopramide, and postoperative medical complications leading to a debilitated clinical state.

The mechanism of atrial flutter alternans was investigated by observing the effects of ventricular systole on flutter intervals in a patient with atrioventricular dissociation. Interval measurements were made both from atrial electrograms recorded from an esophageal electrode, and from surface ECG recordings. Flutter cycle intervals that occurred during a well-defined period subsequent to ventricular systole were consistently prolonged by up to 30 msec relative to the baseline flutter cycle interval. This prolongation was observed in two vastly different electrode configurations, implying that motion artifact was not predominantly responsible. We concluded that, by altering the characteristics of the flutter reentry circuit, transient increases in atrial volume and/or pressure arising during ventricular systole were responsible for the lengthening of the flutter cycle intervals.

Double lung transplantation has been successfully introduced for patients with end-stage pulmonary disease and preserved cardiac function. An advantage of this operation compared with heart-lung transplantation is retention of the recipient's heart. The operative dissection, however, may lead to interruption of sympathetic and parasympathetic pathways to the heart and consequent denervation of the native heart. The cardiac innervation of seven double lung transplant recipients was investigated by the heart rate response to carotid sinus massage, the Valsalva maneuver, intravenous injection of atropine, and exercise. Five single lung and two heart-lung transplant recipients were studied for comparison. Of the seven double lung transplant recipients, three had abnormal responses to carotid sinus massage, six to the strain phase of the Valsalva maneuver, and five to the release phase of the Valsalva maneuver. Three of six double lung transplant recipients tested had no response to intravenous injection of atropine, and five of seven patients had an abnormal recovery of heart rate after maximal exercise. No patient had a normal response to all interventions, and three patients had responses compatible with complete cardiac denervation. It is concluded that cardiac denervation may occur after double lung transplantation, most likely caused by surgical interruption of sympathetic and parasympathetic pathways during dissection of the recipient's trachea.

The testes of an autopsy sample of 56 patients with acquired immunodeficiency syndrome (AIDS) and systemic opportunistic infections were studied for the presence and type of testicular infection. Light-microscopic evidence of opportunistic organisms (cytomegalovirus, Mycobacterium avium-intracellulare, and Toxoplasma) was present in 22 cases (39%). Based on the prevalence and histologic features of the testicular infections and the biological characteristics of the specific organisms, the possible sexual transmission of opportunistic organisms in AIDS is discussed.

Malignant lymphoma of the heart was found at autopsy of two homosexual men with acquired immune deficiency syndrome (AIDS). Both patients had symptoms and signs of cardiac dysfunction, and it is likely that the immediate cause of their deaths was related to the cardiac tumors. In both cases, there was lymphomatous involvement of other organs, but the heart was the predominant site of disease. There was prominent endocardial and myocardial involvement, and both tumors were high grade large cell lymphomas with plasmacytoid features. In both instances, the lymphomas were diagnosed only at the autopsy, despite extensive antemortem cardiac evaluation in one patient. The clinicopathologic correlation, gross pathologic and histologic findings of the tumor, and their pattern and distribution suggest a de novo origin of the lymphoma in the heart in these two patients. Lymphomatous infiltration of the heart should be suspected in patients with AIDS who have cardiac symptoms.

A simple analog circuit is described which is capable of measuring on a beat-to-beat basis P-R, R-P, P-P, and R-R intervals during sinus rhythm and paroxysmal supraventricular tachycardia. In addition the circuit will emit a pulse when the consecutively alternating P and R wave sequence is interrupted thereby signalling a trigger problem or a change in rhythm. The operation of the device requires proper P and R wave sensing and provides outputs which are linear over a range of rates which are applicable to the human heart.

Two homosexual men presented with primary malignant lymphomas of the anorectum. Each patient presented with a painful mass, diagnosed by biopsy and immunologic cell marker studies. One patient, who had a reversed T4/T8 cell ratio, developed a local relapse of the tumor 11 months after radiotherapy, and Pneumocystis carinii pneumonia. The other patient, with a normal T4/T8 ratio, remained lymphoma-free and without evidence of opportunistic infection 25 months after combined chemotherapy and radiotherapy. Anorectal pathologic findings in homosexual men includes proctitis, inflammatory stricture, fissure, or anal warts. Malignant anorectal diseases, such as Kaposi's sarcoma, and cloacogenic or squamous cell carcinomas have been described in homosexual men. Primary malignant lymphoma of the anorectum is rare in both the homosexual and general populations.

We reviewed the records of 501 patients with ectopic pregnancy (EP) seen at the Kings County Hospital during a five-year period (January 1973-December 1977). Our population characteristics and anamnestic data correlated well with those reported in the literature, except for lower incidence of a previous pelvic infection. Abdominal pain, amenorrhea, and vaginal bleeding were the most common presenting symptoms. While the ultrasound studies demonstrated adnexal masses of a non-specific nature, the laparoscopy constituted an accurate diagnostic tool. Ruptured EP was found in 339 patients (67.6%). Salpingectomy only was the mode of treatment in 369 cases (73.6%). In 28.4% of the cases there a microscopic evidence of chronic inflammatory changes of the tube. There were two fatalities. This study appears to indicate an increasing incidence of EP in our institution, along with, and despite, a decreasing frequency of chronic pelvic inflammatory disease in these patients.

A 523-year-old man with recurrent ventricular tachycardia two months post myocardial infarction is described. The tachycardia resulted in low output and heart failure at the time of presentation. Following electrocardioversion of ventricular tachycardia, sinus rhythm would last for only a few seconds, and ventricular tachycardia could not be terminated or prevented by drugs, nor by overdrive pacing. Over a 20-hour period, asynchronous right ventricular pacing at 30/min resulted in repeated random interruption of successive paroxysms of ventricular tachycardia, resulting in maintenance of sinus rhythm about 60 to 70% of the time. This produced marked hemodynamic improvement and a decrease in the frequency of paroxysms of tachycardia which, however, continued to recur once every few days. Despite their reduced frequency, these paroxysms continued to be resistant to drugs and had to be terminated by cardioversion. At this point it was discovered that rapid atrial pacing was able to terminate the patient's tachycardia reliably and reproducibly. A permanent right atrial externally activated radio frequency pacemaker device was inserted and over the ensuing eighteen-month period the patient self-terminated over fifty discrete episodes of ventricular tachycardia.

A three-factor cross of Saccharomyces cerevisiae involving the cap1, ery1, and oli1 loci was done, with partial pedigree analyses of 117 zygotes. First, second, and third buds were removed and the genotypes of their diploid progeny determined, along with those of the residual zygote mother cell. Results were analyzed in terms of frequencies of individual alleles and of recombinant genotypes in the dividing cells. There is a gradual increase in the frequency of homoplasmic cells and in gene frequency variance during these three generations, as would result from stochastic partitioning of mtDNA molecules between mother and bud, probably coupled with random drift of gene frequencies in interphase cells. These phenomena are more pronounced for buds than for mothers, suggesting that buds receive a smaller sample of molecules. End buds are more likely to be homoplasmic and have a lower frequency of recombinant genotypes than do central buds; an end bud is particularly enriched in alleles contributed by the parent that formed that end of the zygote. Zygotes with first central buds produce clones with a higher recombination frequency than do those with first end buds. These results confirm previous studies and suggest that mixing of parental genotypes occurs first in the center of the zygote. If segregation were strictly random, the number of segregating units would have to be much smaller than the number of mtDNA molecules in the zygote. On the other hand, there is no evidence for a region of the molecule ("attachment point") which segregates deterministically.

We present a case of an 18-year-old man with a history of palpitations in whom episodes of paroxysmal supraventricular tachycardia were easily initiated by administered atrial premature beats. In all 15 control episodes of tachycardia, functional left bundle branch block (LBBB) seen at the onset, resolved within 10-20 cycles (mean, 13.1 +/- 0.95). The tachycardia ended with the normalized QRS complex in each episode. Eleven episodes ended because of block within the antegrade pathway (ended with a P-wave), and four episodes stopped because of block within the retrograde pathway (ended without a P-wave). During the administration of isoproterenol (1 mg/min IV) all six episodes of tachycardia had LBBB but these did not end when LBBB disappeared spontaneously. When LBBB subsided, the mean tachycardia cycle interval shortened from 328.5 +/- 1.4 to 264.2 +/- 2.1 ms (p less than 0.001). Each episode of tachycardia was then terminated by carotid sinus massage. The disappearance of LBBB in control conditions presented the retrograde and antegrade limbs of the reentrant circuit with an early impulse that stopped the tachycardia. After isoproterenol administration, the tachycardia did not end following disappearance of LBBB, thus enabling the tachycardia cycle interval to shorten by a mean of 64.3 +/- 1.9 ms. This extent of tachycardia acceleration is diagnostic of the participation of a concealed, left free-wall bypass tract.

An immunopathologic analysis of the testes of 20 homosexual acquired immune deficiency syndrome (AIDS) patients was performed to investigate the hypothesis that the testicular atrophy of these patients represents an immune-mediated process. The findings were compared to those in a control group of heterosexual men without AIDS. The testes of the homosexual AIDS patients showed an overall lower degree of spermatogenesis with more prominent interstitial inflammation and thickening of the tubular basement membrane. However, direct immunofluorescence and immunoperoxidase studies failed to demonstrate significant differences in the prevalence of immune complex deposits along the tubular basement membrane in the two study groups. No electron-dense deposits were demonstrated in cases examined ultrastructurally. Therefore, this study does not support the hypothesis that the testicular atrophy of homosexual AIDS patients is a manifestation of autoimmune orchitis. Further studies are needed to elucidate the pathogenesis of the testicular atrophy in AIDS, as this appears to be a specific manifestation of the disease.

Studies were performed to determine the chronotropic effect of acetylstrophanthidin during constant infusion through cannulation of the sinus nodal artery. Ten mongrel dogs weighing 13.5 to 18 kg were studied under sodium thiamylal anesthesia. Epicardial atrial and ventricular electrograms were recorded. The sinus nodal artery was cannulated and infused for 20 minutes at a rate of 2 cc/min with a solution containing acetylstrophanthidin, 0.5 microng/cc. Mean results for the group of 10 animals were determined. There was a gradual acceleration of the atrial rate of 45 beats/min after 6 to 8 minutes of infusion. The peak atrial rate of 175 beats/min was achieved by 10 to 12 minutes. This tachycardia persisted for 2 to 4 minutes without atrioventricular block or premature beats. By 12 to 14 minutes, there was a gradual slowing of atrial rate followed by bradycardia, sinus pauses and atrial arrest. Sinus nodal arterial infusion of acetylstrophanthidin produces an initial positive chronotropic effect and, if maintained, a depression of atrial rate and, terminally, atrial arrest. The gradual time course of development and decline of the tachycardia suggests that the "paroxysmal" atrial tachycardia caused by digitalis excess is the result of enhanced pacemaker automatically rather than reentry, and thus is not truly paroxysmal.

Four cases of paroxysmal atrial tachycardia are described in whom rate related left bundle branch block (LBBB) was often present which persisted indefintely and showed no signs of spontaneous disappearance. Transient slowing of the tachycardia by carotid sinus massage in each case eliminated LBBB and this led to tachycardia acceleration. The tachycardia acceleration was traceable to a shortening in ventriculoatrial conduction. These observations proved the participation of a left sided bypass tract in the tachycardia circuit in each of these cases.

Crosses were made between strains carrying a nuclear control factor (NC) and strains classified with respect to their omega allele (omega+ or omega-). The characteristic asymmetrical transmission was always observed (as was seen) in crosses not involving the omega factor. The analysis of functional recombinants in a cross involving an NC factor has indicated that the absence of the omega effect may be caused by a restriction in the zygote of the recombination of mitochondrial DNA molecules.

The pertinent clinical data and histologic features of the testes in 57 autopsied acquired immunodeficiency syndrome (AIDS) patients were analyzed and compared with those of 55 age-matched control patients without AIDS. The testes of the AIDS patients showed a significantly lower degree of spermatogenesis (determined by a testicular score count), as well as more prominent thickening of the basement membrane and interstitial fibrosis when compared with the controls. While the precise cause of testicular atrophy in AIDS patients remains to be determined, the chronicity of the disease, prolonged fever, malnutrition, testicular infection, and chemotherapy are all contributing factors. Since the vast majority of the studied AIDS patients were homosexual and most control patients were heterosexual, the observed testicular changes can be ascribed to AIDS and/or homosexuality. Because of a high prevalence of sexually transmitted diseases, antisperm antibodies, and possible zinc deficiency and endocrine disorders, homosexual men appear predisposed to tubular atrophy. Conversely, AIDS-related factors, such as a direct toxic effect of the human immunodeficiency virus on germinal epithelium or as yet undetermined endocrine imbalances might exert a detrimental effect on the testis independent of homosexuality.

We describe a unique case of products of conception retained in the myometrium, and producing masses which were misdiagnosed as uterine myomas. To our knowledge, no similar case has been reported previously. The etiology of this phenomenon is thought to be an artificial implantation of the placental tissue at the time of curettage.

A large polypoid uterine mas was composed to two distinct and separate parts: a malignant mixed müllerian tumor (MMMT) and a benign mixed mesenchymal tumor (BMMT). It was considered a collision of two neoplasms rather than a malignant degeneration of the BMMT. Malignant transformation of benign mesenchymal uterine tumors is a controversial concept which is difficult to prove or disprove. Concerning the histogenesis of MMMT it appears, at least in some cases, that they originate not from a single multipotential mullerian cell, but rather from two, a stromal cell and an epithelial cell. It is suggested furthermore, that in certain instances presence of one neoplastic component, e.g., adenocarcinoma, can incite proliferation of the second, sarcomatous element of the MMMT.

Malignant lymphoma developed in the dorsum of the hand in a patient with a long-standing postmastectomy lymphedema. The tumor subsequently spread to involve skin of the forearm and arm. Growth and spread of malignant cells within the stagnant dilated lymphatics are the likely cause of the characteristic nodular dissemination of the tumor in a lymphedematous extremity, regardless of the type of neoplasm.

A 56-year-old woman had paroxysmal atrial tachycardia (PAT) that was recurrent, drug-resistant and required frequent electroversion. The mode of onset and termination of initiated episodes of PAT suggested an AV junctional reentrant mechanism. The problem was successfully managed by a permanent electrode implanted transvenously in the coronary sinus and connected to a subcutaneous radio frequency receiver. For the past 24 months the patient has successfully terminated all episodes of PAT (at least 60) by activating an external radio frequency transmitter that transmits impulses to the implanted receiver and electrode catheter. Conversion to sinus rhythm requires 5 seconds or less of pacing.

Bowel necrosis is an uncommon complication of pancreatitis. Two patients are reported who developed ileocecal and descending colon changes as a result of ischemia following severe pancreatitis. Arteriography in one patient confirmed the presence of intraluminal thrombi.

We describe a patient with peptic ulcer of the stomach penetrating into the liver, in whom diagnosis was made by histological examination of the gastroscopic biopsy. The liver tissue affected by this local "peptic hepatitis" displayed marked inflammatory and regeneratory atypia that could raise suspicion of an adenocarcinoma. The possibility of finding liver cells and tissue (or pancreatic and splenic tissues) in the gastric biopsy and brushing/washing material should be kept in mind in cases of large peptic ulcers.

Dantrolene sodium is a drug used in the treatment of spasticity and malignant hyperthermia. It is known to have a myorelaxant effect related to inhibition of the "release" of calcium by the sarcoplasmic reticulum of striated skeletal muscle. A direct cardiac effect which has only recently been suspected was demonstrated in vitro on isolated preparations of sheep Purkinje fibres and ventricular myocardium. Dantrolene caused a spectacular lengthening of the duration of the action potential of Purkinje fibres. This could be due either to an action on the slow calcium current or to stimulation of an ingoing sodium current sensitive to tetrodotoxin (TTX). This effect on the cardiac action potentials could explain the antiarrhythmic properties of dantrolene sodium during attacks of malignant hyperthermia.

We report two cirrhotic patients who succumbed to massive rectal bleeding. The source of this hemorrhage remained undiscovered clinically despite endoscopy, a bleeding scan, and celiac angiogram in one patient. Autopsy revealed that the source of the bleeding was rectal varices in both cases.