Climate effects on late-season flight times of Massachusetts butterflies.

Although the responses of living organisms to climate change are being widely investigated, little attention has been given to such effects late in the growing season. We studied the late-season flight times of 20 species of butterflies in a geographically limited region, the state of Massachusetts in the USA, by examining change in dates of flight over a 22-year period and in response to average monthly temperature and precipitation. By analyzing the last 10% of each year's observations reported by observers of the Massachusetts Butterfly Club, we found that seven species remain in flight significantly later into the fall than they did two decades earlier, while two species show reduced late-season flight. Life history characteristics of the species, particularly voltinism and average fall flight dates, influenced whether warmer fall months led to increases or decreases in fall flight. Warmer Novembers often led to later fall flight, and wetter Augusts usually extended fall flight. These results document the effects of climate on late-season flight times of butterflies, add to an understanding of how warmer autumn conditions alter the phenology of different butterfly species, and show the usefulness of citizen science data.

Aldose reductase expression in human diabetic retina and retinal pigment epithelium.

The conversion of glucose to sorbitol by aldose reductase (AR) and its subsequent intracellular accumulation have been implicated in the pathogenesis of diabetic cataracts. There is also evidence linking AR activity with retinal capillary basement membrane thickening in galactosemic rats, suggesting a possible role in diabetic retinopathy. In this study, we explored one feature of this issue by examining diabetic and nondiabetic eyes for immunoreactive AR. AR was immunohistochemically undetectable in the retinal pigment epithelia (RPE) and neural retinas of nondiabetic human eyes. Weak, focal staining for AR was present unilaterally in the RPE of 1 of 11 diabetic patients without pathologic ocular findings and in 43% of diabetic patients with mild ocular findings. Retinal positivity was found (unilaterally) in only 2 of 19 individuals from either of these mildly affected groups. Fifty-five percent of patients with background retinopathy demonstrated AR positivity in the RPE, and half of these expressed AR in the RPE of both eyes. Of the individuals with proliferative diabetic retinopathy, 87.5% showed bilateral staining in the RPE. Retinal positivity was present in 36% of background retinopathy and 75% of proliferative retinopathy cases, demonstrating a positive correlation between AR expression and the severity of the disorder. In weakly staining retinas, only the ganglion cell bodies, nerve fibers, and Müller cells were positive, whereas in intensely staining cases, virtually the entire retina, except for the rod outer segments, was positive. Eyes from patients who had had diabetes less than or equal to 6 yr were negative for AR, but those from long- term-diabetic patients (14-45 yr) manifested positively.(ABSTRACT TRUNCATED AT 250 WORDS)

Highly diverged homologs of Saccharomyces cerevisiae mitochondrial mRNA-specific translational activators have orthologous functions in other budding yeasts.

Translation of mitochondrially coded mRNAs in Saccharomyces cerevisiae depends on membrane-bound mRNA-specific activator proteins, whose targets lie in the mRNA 5'-untranslated leaders (5'-UTLs). In at least some cases, the activators function to localize translation of hydrophobic proteins on the inner membrane and are rate limiting for gene expression. We searched unsuccessfully in divergent budding yeasts for orthologs of the COX2- and COX3-specific translational activator genes, PET111, PET54, PET122, and PET494, by direct complementation. However, by screening for complementation of mutations in genes adjacent to the PET genes in S. cerevisiae, we obtained chromosomal segments containing highly diverged homologs of PET111 and PET122 from Saccharomyces kluyveri and of PET111 from Kluyveromyces lactis. All three of these genes failed to function in S. cerevisiae. We also found that the 5'-UTLs of the COX2 and COX3 mRNAs of S. kluyveri and K. lactis have little similarity to each other or to those of S. cerevisiae. To determine whether the PET111 and PET122 homologs carry out orthologous functions, we deleted them from the S. kluyveri genome and deleted PET111 from the K. lactis genome. The pet111 mutations in both species prevented COX2 translation, and the S. kluyveri pet122 mutation prevented COX3 translation. Thus, while the sequences of these translational activator proteins and their 5'-UTL targets are highly diverged, their mRNA-specific functions are orthologous.

Symptomatic deep venous thrombosis of the arm associated with permanent transvenous pacing electrodes.

From October 1970 to May 1977, a total of 212 pacemakers were implanted at the Milton S. Hershey Medical Center of Pennsylvania State University, Hershey. During this period, we encountered five patients with symptomatic thrombosis of the subclavian vein, a rate for this complication of approximately 2 percent. Although this complication was reported only rarely prior to 1976, we believe that symptomatic subclavian thrombosis after insertion of a transvenous pacemaker electrode occurs more frequently than previously suspected. The etiology, pathogenesis, and treatment of this interesting condition are discussed.

Effect of temperature during potassium arrest on myocardial metabolism and function.

Past studies have not established the optimal myocardial temperature range for hyperkalemic arrest but have generated controversy regarding the safety of exposing the myocardium to more profound levels of hypothermia. We therefore used the isolated working rat heart model of ischemic arrest to study the metabolic and functional effects of cardioplegia at the full range of temperatures pertinent clinically. Experimental conditions were designed to reliably control and maintain myocardial temperature during the 60 minute arrest period. We found that nearly full recovery of function occurred when hearts were arrested at or below 16 degrees C. High-energy phosphate levels measured immediately after arrest were better maintained at 4 degrees and 8 degrees C, despite evidence of decreased anaerobic glycolysis. When measured after the recovery period, high-energy phosphate levels returned to somewhat less than control levels in all groups arrested at or below 24 degrees C. Myocardial glucose utilization was best preserved in hearts arrested at or below 12 degrees C. We found no evidence that greater myocardial edema resulted from arrest at colder temperatures. Severe and permanent damage was observed when hearts were arrested at or above 28 degrees C. In this model, therefore, the best overall metabolic and functional protection occurred when hearts were maintained at 12 degrees C or below potassium-induced cardioplegia. Our results support the idea that cold injury to the heart does not occur and that colder temperatures provide better protection from ischemic myocardial injury.

Human pulmonary dirofilariasis presenting as a solitary pulmonary nodule.

A case of human pulmonary dirofilariasis had positive serologic testing postoperatively. Increased awareness of this entity as a cause of solitary pulmonary nodules may lead to preoperative serologic and intradermal testing, and to the possibility of arriving at a preoperative diagnosis.

Effect of perfusate temperature on myocardial protection from ischemia.

During reperfusion, functional and metabolic recovery of the isolated working rat heart from one hour of ischemia was best in hearts selectively cooled at the onset of the ischemic interval by perfusion with 5 to 10 ml. of 10 degrees C. or 15 degrees C. Krebs-Henseleit buffer. Hearts similarly perfused at 4 degrees C., 20 degrees C. recovered significantly less well or not at all. Immediately after the hour of ischemia and prior to reperfusion, the absolute levels of glycogen and high-energy phosphates were best in the hearts perfused at 4 degrees C. However, metabolic function was best preserved in those perfused at 10 degrees C. and 15 degrees C., as evidenced by rapid recovery of high-energy phosphates and glycogen to control levels compared to metabolic deterioration in the 4 degrees C. group.

Early calcific stenosis of aortic and mitral Ionescu-Shiley valves in a patient with bioprosthetic infection.

The clinical course of a patient with bioprosthetic failure of aortic and mitral Ionescu-Shiley valves (which contain bovine pericardial leaflets) is presented. Failure occurred in less than 4 months and was due to infection that resulted in calcification and severe stenosis. On examination of tissue specimens under light and electron microscopes, the pathological process was seen to be similar o that occurring with infected porcine prostheses.

Delayed recurrent massive thromboembolism through a vena caval clip after pulmonary embolectomy.

A case of recurrent massive pulmonary embolization through a modified Miles' clip two weeks after successful emergency pulmonary embolectomy is reported. Vena caval ligation is probably a safer alternative in these critically ill patients.

Use of cold cardioplegic solution for vein graft distention and preservation: a light and scanning electron microscopic study.

To evaluate the effect of a cardioplegic solution on the endothelium of the saphenous vein, portions of this vein were harvested from each of 5 patients undergoing coronary artery bypass operation. Each sample was divided into five segments. One segment was distended with heparinized saline solution, one with heparinized blood, and one with heparinized cardioplegic solution (25 mEq of potassium per liter). All of the distending solutions were kept at 10 degrees C, and pressure was carefully limited to 200 mm Hg. The fourth segment of vein was distended with heparinized saline solution but no effort was made to limit distending pressure, and the fifth segment was not distended. All samples were then examined with light and scanning electron microscopy. There were no great morphological differences in the endothelium of veins distended to 200 mm Hg with saline solution, blood, or cardioplegic solution. The morphology of these samples compared favorably with the control vein endothelium although scattered areas of endothelial disruption were present in every sample. Veins distended without pressure control showed massive endothelial disruption. The particular solution used to distend the sephenous veins is not as important as limiting the distending pressure.

Anterior spinal artery syndrome with chronic traumatic aortic aneurysm.

Shortly after severe blunt chest trauma, a young man experienced neurological symptoms suggestive of a spinal cord lesion at the lower thoracic level. The symptoms resolved at first, but then recurred 3 years later and progressed slowly. Neurological workup failed to define the cause until a thoracic aortogram showed an aneurysm in the middle portion of the descending aorta in close proximity to a vessel supplying the anterior spinal artery. After the operative repair with precautions taken to avoid further neurological injury, the neurologic deficit resolved partially. Because of the potential for symptomatic spinal cord ischemia resulting from lesions of the aorta, angiographic delineation of the spinal cord blood supply is valuable in planning operative repair.

Intrapleural instillation of quinacrine for treatment of recurrent spontaneous pneumothorax.

We used intrapleural instillation of quinacrine hydrochloride in 20 patients (Group A) with recurrent spontaneous pneumothorax (one bilateral) and compared their clinical course with 19 patients who underwent thoracotomy and scarification or pleurectomy (Group B) and 63 patients treated by tube thoracostomy alone (Group C). In Group A, there was one complication of treatment, a pneumothorax immediately following tube removal, which necessitated repeat tube thoracostomy, and there was one late ipsilateral recurrence 2 years after treatment. These 20 patients with 21 recurrent spontaneous pneumothoraces treated with intrapleurally administered quinacrine have been followed for from 6 months to more than 4 years with only one late recurrence on the treated side. Eight patients in Group B had postoperative complications: 2 patients who had had pleurectomy required reoperation for postoperative bleeding; lobar pneumonia developed in 3; 1 had lack of total expansion of the lung; an intrathoracic hematoma developed in 1; and an ipsilateral pneumothorax necessitating tube thoracostomy developed in 1. In Group C, the rate of recurrence of pneumothorax was 23% during the first year following treatment. Intrapleural instillation of quinacrine is a simple, low-risk, reliable, and effective treatment for recurrent spontaneous pneumothorax, and is equally as effective as thoracotomy and scarification.

Recent experience with tuberculous pericarditis.

Twelve patients with tuberculous pericarditis were found among 1,194 patients with tuberculosis treated at the University of Texas Medical Branch over a 10-year period, an incidence of 1%. Surgical treatment was undertaken in 4 patients, and the rest were treated medically. The surgically treated patients had no major complications, and none of them died. In the medically treated group, however, 1 patient died, 1 had an anaerobic empyema, and 1 experienced respiratory arrest. In addition, the average hospital stay was 33 days less in the surgically treated group. Early surgical intervention should be carried out in patients with tuberculous pericarditis who do not respond promptly to adequate antituberculosis chemotherapy.

Similarity of clinical and laboratory results obtained with microporous teflon membrane oxygenator and bubble-film hybrid oxygenator.

For 80 elective clinical cardiopulmonary bypasses we alternately used either a commercial microporous Teflon membrane oxygenator or a commercial hybrid bubble-film oxygenator. Setup time was a little longer with the membrane unit (20 minutes), but priming volume (2,250 ml) was the same. No problems were encountered with the hybrid oxygenator. However, despite our monitoring of additional variables, including shim and inlet pressure and recirculation flow, gas exchange abnormalities were encountered in 5 patients on whom the membrane oxygenator was used; in 4 of these cases the abnormalities were encountered prior to our recognition of the potential for occasional internal shunting with this device. There were no hospital deaths. When the two groups, matched except for oxygenator selection, were compared, there were no significant differences clinically or hematologically. For cardiopulmonary bypass of 2 hours or less, both oxygenators studied are definite improvements over previous silicone membrane and high-gas-flow bubble oxygenators. However, lower cost and reduced complexity favor the hybrid oxygenator.

Myocardial stimulation impedance: the effects of electrode, physiological, and stimulus variables.

With exposed metal at the electrode tissue interface (8 mm2, 28 mm2, 57 mm2), myocardial threshold stimulation impedance increased as pulse duration was lengthened, with left ventricular intramyocardial stimulation, and with the smaller surface area electrode. An 0.5 mm2 differential-current-density electrode, which eliminated direct metal-to-tissue contact at the electrode-myocardial interface, was associated with notably higher impedances than each of the three metal tip electrodes and did not show increasing impedance levels with changes in pulse duration, confirming the minimization of polarization energy losses with this device. The majority of electrode, electrode tissue interface, and myocardial variables that are characterized by high threshold stimulation impedance are associated with low threshold energy requirements for pacing and reduced pacemaker power source drain. No accurate information about sensing impedances can be derived from current knowledge of pacing impedance.

Tracheostomy in infants and young children.

Seventy-three tracheostomies performed in children three years of age and under in a 52-month period are discussed. Thirty-six were under one year of age. Forty-one were performed for upper airway obstruction, 23 for ventilation or suction, and nine for a combination of upper airway obstruction and lower bronchopulmonary disease. Operative complications developed in 10 patients, and postoperative complications in 16. The most common complication was interstitial air; the most deadly was obstruction of the cannula. There were 20 deaths. Sixteen were due to the patients' diseases; four were due to complications of tracheostomy. If serious operative and postoperative complications are avoided, the important factors determining prognosis are the patient's age and the condition for which the tracheostomy was done. The long term results in these patients show this to be true for both survival and duration of tracheostomy.

Helminths from a stranded manatee in the Dominican Republic.

Endangered West Indian manatees (Trichechus manatus) are known to be parasitized by a number of helminths and ectoparasites. Records of parasitic associations exist for Florida, Mexico, Guyana, Brazil, Cuba and recently for Puerto Rico. Parasites of manatees in other Caribbean areas have not been documented, particularly from Hispaniola. We report on the occurrence of a species of nematode and of two trematodes from a 238-cm male manatee from Portillo (19 degrees 20' N, 69 degrees 35' W), Las Terrenas, in the Dominican Republic. Three species of helminths were collected, including the opisthotrematid Cochleotrema cochleotrema, the ascarid Heterocheilus tunicatus, and the paramphistomid trematode Chiorchis fabaceus. The documentation of these helminths constitutes the first record of these parasites and host relationships for Hispaniola and the second for the northeastern Caribbean.

Pilum pilum gen. et sp. n. (Acanthocephala: Echinorhynchidae) from freshwater fishes of the southeastern United States.

Pilum pilum gen. et sp. n. is described from the warmouth, Lepomis gulosus (Cuvier); brown bullhead, Ictalurus nebulosus (Lesueur); yellow bullhead, I. natalis (Lesueur); redbreast sunfish, L. auritus (Linnaeus); bluegill, L. macrochirus Rafinesque; spotted sunfish, L. punctatus (Valenciennes); and redfin pickerel, Esox americanus (Gmelin), from the Alabama River Drainage, brown bullhead from the Mobile Bay Drainage in Alabama, and pirate perch, Aphredoderus sayanus Gilliams, from an Atlantic Coast drainage in Georgia. The new genus most closely resembles the genus Acanthocephalus; it differs from this genus in having a distinctive pear-shaped proboscis, a long neck, and hooks which abruptly differ in size.