Landscape epidemiology of Batrachochytrium dendrobatidis in central California

Amphibian chytridiomycosis (caused by Batrachochytrium dendrobatis; Bd) was first identified in 1998 and has since been implicated in numerous amphibian declines worldwide. Most researchers have since investigated broad‐scale geographic and taxonomic occurrences of the pathogen in tropical lotic or cool montane systems. In this study, we analyzed how environmental factors, land use practices, and landscape structure may affect the dynamics of the pathogen's distribution in a landscape dominated by lentic systems within a region of Mediterranean climate. We quantified the occurrence of Bd testing the six resident amphibian species that occur in 54 isolated perennial and ephemeral ponds in central California between May and June annually from 2004 to 2007. The geographic distribution of Bd within the landscape varied markedly between years. Inter‐annual variation in climate affected the pond landscape structure indicating that climate conditions indirectly influence the distribution of the pathogen. Fourteen ponds, 12 perennial and 2 ephemeral, were positive for Bd≥3 yr of the study and were treated as Bd hotpots for comparative purposes. Occurrences of Bd within the landscape were spatially autocorrelated and ponds within ~1000–1500 m of Bd hotspots were more likely to test positive. Local land use, (presence/absence of grazing or recreational activity and developed lands), did not influence Bd status of a pond, indicating that the most likely means of Bd transmission between ponds may be waterfowl and/or amphibians.     

Transurethral prostatectomies; a review of 560 cases

Spontaneous pneumoperitoneum most often occurs following ruptured peptic ulcer. In 80 to 85 per cent of cases of perforated ulcers, free intraperitoneal air is demonstrable. There have been reported three cases in which air was present without demonstrable cause, without peritoneal irritation or peritonitis. This presentation adds a fourth. Examination of a patient with acute disease of the abdomen should include not only a roentgenogram with the patient supine but films made in the left lateral decubitus position and/or upright position to demonstrate free air. The radiologist should be ready and willing to consult with the surgeon at the time of examination. Attention is called to a sign described recently by Rigler in supine films, namely, the visibility of both the inside and the outside of the intestinal lumen. Another sign in the supine film, namely the contrast of air against the peritoneal reflections, is described.     

Multiple myeloma; a review of 26 cases

Multiple myeloma is a rare, malignant disease of bone marrow which affects principally the vertebrae, ribs, pelvis and skull but may involve any part of the skeleton. Severe demineralization and destructive lesions of bones, producing severe pain and debility, are distinctive features. The disease is further distinguished by abnormalities of blood proteins and in some cases by the excretion in the urine of Bence-Jones protein, which seldom, if ever, is found in association with any other disease.X-ray examination is frequently helpful. In 22 of 24 cases (of a series of 26 cases) in which films were available, definite abnormalities were noted. Spontaneous fractures, particularly of vertebrae, are common. The diagnosis of the disease rests on the identification of the myeloma cell. This is best accomplished by aspiration of bone marrow. In several of the 26 cases in the series diagnosis was made by a neurosurgeon at the time of operation to relieve pressure on the spinal cord. The myeloma cell has a very characteristic appearance. In the present series the average duration of life after the onset of symptoms was only nine months. One patient, however, survived for at least ten years.     

Therapeutic donor insemination; a review of 440 cases

Of 399 patients inseminated therapeutically with the semen of a donor, 303 became pregnant, the great majority of them within six months of the time inseminations were begun. The average number of inseminations was 6.2 and the average number of menstrual cycles over which they were carried out was 3.55. The greatest number of pregnancies occurred between the twelfth and the fifteenth day of the menstrual cycle. Seven patients had four pregnancies by this method, 17 had three and 59 had two. Emotional problems related to children of artificial insemination were far fewer than those associated with adoption.     

Hodgkin's disease; a clinical-pathological review of 150 cases

One hundred and fifty cases of Hodgkin's disease were analyzed in an effort to detect significant clinical-pathological correlations and to elucidate any possible factors of prognostic or etiological importance.A relatively long survival for patients with Hodgkin's paragranuloma was not noted in this series. Instead the survival rate among them was closely parallel to that of patients with classical granuloma. Hodgkin's sarcoma is a more malignant disease with a patient survival rate not more than half that of patients with the granuloma variety. It is not necessarily a disease of older age groups. Great caution must be exercised to avoid including non-Hodgkin's disease tumors under the heading of Hodgkin's sarcoma or paragranuloma. The series reported corresponds with many other reported series of Hodgkin's disease as regards greater incidence in males and longer survival in females. In this series the cases in patients under the age of 15 were all in males. The predominance of initial enlargement of the cervical nodes was again noted in this series, as was the high proportion of negative reaction to tuberculin tests. The incidence of tuberculous lesions in patients who died of Hodgkin's disease was only slightly greater than in those who died of other lymphoma. Site of origin of the disease apparently affects survival time. There was statistical evidence that gonadal activity might influence the equilibrium of the disease. Lymph node bacteriological cultures were not remarkable. Brucella organisms were absent. Fertile egg passages for detecting possible viral agents revealed increased egg mortality and cutaneous sensitivity reactions to the harvested amniotic fluid.     

The influence of landscape and environmental factors on ranavirus epidemiology in a California amphibian assemblage

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Prostatectomy in a county hospital; a review of 677 cases in a six-year period

Transurethral procedures were used in 620 of 677 cases in which prostatectomy was done (principally by residents supervised by a urologist) at a county hospital in a six-year period. Open operations were used in the other 57 cases. Results were classified as "excellent" in 46.8 per cent of the transurethral cases and as "good" in 36.3 per cent.     

Prostatectomy in private practice; a review of 589 cases in a five-year period

Prostatectomy was done in 589 cases in a five-year period. The operation was done transurethrally in 530 cases of benign disease and in 50 cases of malignant lesions. In six cases of malignant disease and three of benign, open procedures were used. Results of transurethral prostatectomy were considered good or excellent in 94.4 per cent of the cases of benign hypertrophy and in 92 per cent of the cases of carcinoma. It was felt that radical perineal prostatectomy was advisable for early operable cases of carcinoma, but that the transurethral procedure was more suitable in almost all cases of benign hypertrophy.     

Decidual reaction of the cervix; a review of 27 cases

Decidual reaction of the cervix is a benign growth produced by the hormones of pregnancy. These reactions or changes in the cervix are present in about 20 per cent of normal pregnant women. They may look like cancer but are not cancer. They are benign lesions. Bleeding is a common symptom and may occur at any stage of pregnancy. The presence of decidual reaction does not predispose to spontaneous miscarriage. In most cases no treatment is required; in a few light cauterization may be needed to control bleeding. Any suspicious lesion should be biopsied to rule out malignancy. By microscopic examination any experienced pathologist can differentiate a decidual reaction from cancer. The consensus of opinion is to let the pregnant woman deliver, normally, with this benign lesion, for it disappears after the baby is born. If cancer is found during pregnancy, it should be actively treated.     

Carcinoma of the thyroid gland; a review of 106 cases

In a review of 106 cases of carcinoma of the thyroid gland, it was noted that a solitary thyroid nodule is the most outstanding single physical sign in this disease. It should be investigated by biopsy of a specimen removed at operation. Patients and physicians were sometimes guilty of delay in this regard. Papillary carcinoma involved multiple foci within the gland in at least half of the cases and there was a high incidence of regional lymph node metastasis associated with this type. Doubt was cast on conclusions by other investigators that carcinoma of the thyroid rarely is lethal in patients less than 40 years of age.     

Genetic epidemiology of the Sudden Oak Death pathogen Phytophthora ramorum in California

A total of 669 isolates of Phytophthora ramorum, the pathogen responsible for Sudden Oak Death, were collected from 34 Californian forests and from the ornamental plant-trade. Seven microsatellite markers revealed 82 multilocus genotypes (MGs) of which only three were abundant (>10%). Iteratively collapsing based upon minimum Φ_ST, yielded five meta-samples and five singleton populations. Populations in the same meta-sample were geographically contiguous, with one exception, possibly explained by the trade of infected plants from the same source into different locations. Multidimensional scaling corroborated this clustering and identified nursery populations as genetically most distant from the most recent outbreaks. A minimum-spanning network illustrated the evolutionary relationships among MGs, with common genotypes at the centre and singletons at the extremities; consistent with colonization by a few common genotypes followed by local evolution. Coalescent migration analyses used the original data set and a data set in which local genotypes were collapsed into common ancestral genotypes. Both analyses suggested that meta-samples 1 (Santa Cruz County) and 3 (Sonoma and Marin Counties), act as sources for most of the other forests. The untransformed data set best explains the first phases of the invasion, when the role of novel genotypes may have been minimal, whereas the second analysis best explains migration patterns in later phases of the invasion, when prevalence of novel genotypes was likely to have become more significant. Using this combined approach, we discuss possible migration routes based on our analyses, and compare them to historical and field observations from several case studies.