New management unit for conservation of the Endangered green turtle Chelonia mydas at the Xisha (Paracel) Islands, South China Sea

The Qilianyu cluster of the Xisha (Paracel) Islands has one of the few remaining green turtle Chelonia mydas rookeries in the China region. Genetic samples were obtained from dead green turtle embryos and hatchlings salvaged from post-hatched nests at Middle Island (n = 3), North Island (n = 9) and South Sand (n = 1) of the Qilianyu cluster in 2017-2019. The ~800 bp mitochondrial DNA control region was sequenced from the samples, and 5 haplotypes were identified belonging to 2 documented clades (clades III and VIII), including 2 new haplotypes (CmP243.1 and CmP244.1) and 3 previously reported haplotypes (CmP18.1, CmP19.1, CmP20.1). These results were combined with previously published mtDNA data for the Qilianyu cluster and nearby (~93 km) Yongle Islands indicating a lack of differentiation based on truncated 384 bp control region sequences (exact test, p = 0.0997; FST = 0.015, p = 0.2760), to represent a single Xisha Islands rookery. The rookery at the Xisha Islands was significantly differentiated (p < 0.01) from all 19 management units (MUs) documented in the Indo-Pacific and Japan regions, supporting recognition of the Xisha Islands rookery as a new independent MU. The results will help inform national and international conservation action plans by China and the countries around the South China Sea to protect green turtles in the West Pacific Ocean.

Three decades of stranding data reveal insights into endangered hawksbill sea turtles in Hawai‘i&dagger

Hawksbill sea turtles Eretmochelys imbricata inhabiting the Hawaiian Islands are extremely rare and listed as endangered under the US Endangered Species Act. The paucity of data on basic hawksbill ecology continues to hinder effective management of the species. We analyzed stranding data collected between 1984 and 2018 to gain insights into the distribution, demography, and conservation challenges facing hawksbills in Hawai‘i. In doing so, we present a comprehensive description of the population across developmental stages and rank threats that may be impeding their successful recovery. Over the >30 yr data set, we recorded a total of only 111 juvenile and adult hawksbill stranding events. Interactions with nearshore recreational fishing gear were documented for a large proportion (48.6%) of stranding events in the Hawaiian Islands, identifying this as the primary management challenge for the species. Stranding events were biased towards females (female to male sex ratio of 4.8:1.0), which may be indicative of the population as a whole. Even though the majority of hawksbills nest on the islands of Hawai‘i Moloka‘i, and Maui, the greatest number of juvenile to adult strandings was found to be on the island of Oahu (n = 47). Temporal distribution of the majority of adult hawksbill strandings (72.2%) occurred during a 4 mo period between June and September. We discuss these and other findings that help identify future research and conservation efforts to mitigate anthropogenic threats in Hawai‘i for this enigmatic population.

Active dispersal in loggerhead sea turtles (Caretta caretta) during the 'lost years'

Highly migratory marine species can travel long distances and across entire ocean basins to reach foraging and breeding grounds, yet gaps persist in our knowledge of oceanic dispersal and habitat use. This is especially true for sea turtles, whose complex life history and lengthy pelagic stage present unique conservation challenges. Few studies have explored how these young at-sea turtles navigate their environment, but advancements in satellite technology and numerical models have shown that active and passive movements are used in relation to open ocean features. Here, we provide the first study, to the best of our knowledge, to simultaneously combine a high-resolution physical forcing ocean circulation model with long-term multi-year tracking data of young, trans-oceanic North Pacific loggerhead sea turtles during their 'lost years' at sea. From 2010 to 2014, we compare simulated trajectories of passive transport with empirical data of 1-3 year old turtles released off Japan (29.7-37.5 straight carapace length cm). After several years, the at-sea distribution of simulated current-driven trajectories significantly differed from that of the observed turtle tracks. These results underscore current theories on active dispersal by young oceanic-stage sea turtles and give further weight to hypotheses of juvenile foraging strategies for this species. Such information can also provide critical geographical information for spatially explicit conservation approaches to this endangered population.

Abstract P1-07-06: Immune signatures define and affect prognosis in triple-negative breast cancer subtypes

Background: The tumor immune microenvironment is formed by many distinct and interacting cell populations, and its composition may predict patient's prognosis and response to therapies. Triple negative breast cancer (TNBC) is a heterogeneous disease in which different genomic subgroups have been described (Lehmann, et al. J Clin Invest.2011). Our aim was to integrate the composition of the tumor immune microenvironment with the molecular TNBC subtypes.

Methods: We retrospectively analyzed the composition and the functional orientation of the immune microenvironment of 963 TNBC tumors clustered in 4 main TNBC subgroups (Basal-Like [BL1/2], Immunomodulatory [IM], Mesenchymal/Mesenchymal Stem-Like [MS], Androgen Receptor [AR]) from independent cohorts using transcriptomic profiling. TNBC were stratified based on 9 different immune signatures (Natural Killer [NK], Dendritic Cells [DC], T-Cells [TC], B-Cells [BC], T-Cytotoxic [TC], Interferon [IF], Nuclear Factor-kB [NF-kB], anti-tumor Macrophages [M1] and pro-tumor Macrophages [M2]. We validated our findings using immunohistochemistry.

Results: We report that TNBC molecular subgroups and specific microenvironmental immune signatures are highly correlated. The IM was enriched of almost all the immune modules. On overall TNBC population, the TC (P = 0.01), IF (P = 0.007) and M1 (P = 0.001) signatures were associated with good prognosis. The BL subgroup with a good prognosis was characterized by overexpression of genes specific to M1-macrophages (P = 0.004) and TC-lymphocytes (P = 0.01). In contrast, the poor-prognosis MS expresses markers of cells of monocytic origin and significantly associated with the M2 signature (P = 0.01). The MS subgroup also displays an inflammatory and immunosuppressive signature. Pathological examination revealed that the MS subtype is characterized by a high density of pro-tumor macrophages that likely produce chemokines and cytokines which favor tumor-associated inflammation, resulting in a poor prognosis. In contrast, the AR exhibits low immune and inflammatory signatures.

Conclusions: The distinct immune orientations of the TNBC molecular subtypes pave the way for tailored immunotherapies.

Citation Format: Bottai G, Balazs G, Nagy A, Pusztai L, Szallasi Z, Reis-Filho JS, Santarpia L. Immune signatures define and affect prognosis in triple-negative breast cancer subtypes [abstract]. In: Proceedings of the 2016 San Antonio Breast Cancer Symposium; 2016 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2017;77(4 Suppl):Abstract nr P1-07-06.

Pediatric Sepsis: Clinical Markers

Pediatric sepsis can be caused by infection agents such as viruses, bacteria, protozoa, or their toxins. Clinical features cover a remarkably wide spectrum. Early recognition of the disease and prompt initiation of therapy substantially improve mortality and the outcome of potential complications. After an initial phase of very mild symptoms, the spread of microbes or toxins in the bloodstream presents as septic shock through vasoregulatory disturbance, absolute or relative intravascular volume loss, and consequential tachycardia and hypotension. The most common accompanying symptom is fever. In physical examination, features such as altered mental status, excess respiratory effort, tachycardia, and prolonged capillary refill time are present at an early stage of the disease. Laboratory tests for the assessment of early stage severity and subsequent monitoring of treatment efficacy include point-of-care arterial blood gas analysis and lactate assay. In early stage disease, it is imperative to promptly start adequate antimicrobial and supportive treatment once bacterial cultures have been taken. Despite the availability of a wide range of laboratory and imaging tests today, diagnosis and severity assessment of sepsis still primarily rely on medical history and clinical examination. In light of this, it is possible for trained care providers to detect the early signs of a septic child during repetitive physical examinations. This is still the mainstay of diagnosis and can provide in all care settings a significant reduction in therapeutic delay; this, in turn, helps to reduce sepsis-related mortality and morbidity.

Pediatric Sepsis: Genetic Considerations

The mortality of childhood sepsis continues to be rather high. When it comes to prevention and adequate therapy, individual differences and genetic alterations are becoming more and more important. These may affect molecules involved in pathogen recognition (e.g., lipopolysaccharide-binding protein, mannose-binding lectin, bactericidal/permeability-increasing protein, Toll-like receptors), signal transduction pathways (e.g., cRel), proinflammatory (e.g., tumor necrosis factor-α, interleukin-1 [IL-1], IL-6, IL-8) as well as anti-inflammatory cytokines (e.g., IL-4, IL-10, IL-1 receptor antagonist), members of the coagulation cascade, and other molecules active in the process of systemic inflammatory response syndrome (e.g., heat shock proteins, complement system). The most common genetic polymorphisms are the so-called single-nucleotide polymorphisms, which entail the change of a single base. Genetic mutations have an impact on susceptibility, severity, and outcome of sepsis. Understanding such mutations may improve treatment efficiency; although there is a considerably limited choice of causal treatments today, they may become available upon future developments in genetic therapy.

Dynamics of Virus Shedding and In Situ Confirmation of Chelonid Herpesvirus 5 in Hawaiian Green Turtles With Fibropapillomatosis

Cancers in humans and animals can be caused by viruses, but virus-induced tumors are considered to be poor sites for replication of intact virions (lytic replication). Fibropapillomatosis (FP) is a neoplastic disease associated with a herpesvirus, chelonid herpesvirus 5 (ChHV5), that affects green turtles globally. ChHV5 probably replicates in epidermal cells of tumors, because epidermal intranuclear inclusions (EIIs) contain herpesvirus-like particles. However, although EIIs are a sign of herpesvirus replication, they have not yet been firmly linked to ChHV5. Moreover, the dynamics of viral shedding in turtles are unknown, and there are no serological reagents to confirm actual presence of the specific ChHV5 virus in tissues. The investigators analyzed 381 FP tumors for the presence of EIIs and found that overall, about 35% of green turtles had lytic replication in skin tumors with 7% of tumors showing lytic replication. A few (11%) turtles accounted for more than 30% cases having lytic viral replication, and lytic replication was more likely in smaller tumors. To confirm that turtles were actively replicating ChHV5, a prerequisite for shedding, the investigators used antiserum raised against F-VP26, a predicted capsid protein of ChHV5 that localizes to the host cell nucleus during viral replication. This antiserum revealed F-VP26 in EIIs of tumors, thus confirming the presence of replicating ChHV5. In this light, it is proposed that unlike other virus-induced neoplastic diseases, FP is a disease that may depend on superspreaders, a few highly infectious individuals growing numerous small tumors permissive to viral production, for transmission of ChHV5.

Lymphocytes resided in the thyroid are the main source of TSH-receptor antibodies in Basedow's-Graves' disease?

The source of TSH-receptor antibodies (TRAb) in Basedow's-Graves' disease is still under debate. Previous studies by other groups had found TRAb levels in the thyroid vein higher than or equal to that in the peripheral vein. The aim of the present work was to investigate the suspected presence of this TRAb gradient in 14 Graves' patients who underwent surgery. Interestingly, in 6 patients higher levels of TRAb were measured in the antecubital vein when compared to the thyroid vein, in another 6 there was no gradient and 2 exhibited higher TRAb levels in their thyroid veins. A clear gradient of thyroid hormones in favour of the thyroid vein was also present, while no gradient of TSH, anti-thyreoglobulin and anti-microsomal antibodies, total IgG, IgA and IgM levels and no differences of the CD4+/CD8+ cell ratios were found between the two sampling sites. We conclude that cells other than lymphocytes residing in the thyroid gland must also be involved in TRAb production.

Congener-specific profile and toxicity assessment of PCBs in green turtles (Chelonia mydas) from the Hawaiian Islands

Chemical pollution may play a role in the etiology of fibropapillomatosis in green turtles (Chelonia mydas). In this preliminary study, polychlorinated biphenyls (PCBs) were measured in the livers and adipose fats of green turtles collected after they were stranded on Oahu Island, Hawaii in 1992-1993. Average concentrations of total PCBs were 45-58 ng/g dry weight and 73-665 ng/g in the liver and adipose tissues, respectively. Hexachlorobiphenyls were predominant homologues, PCBs 153 and 138 were dominant congeners in all the turtle tissues. Among the most toxic coplanar congeners, in the order of abundance, were PCB 77 > 126 > 169. Estimated toxic equivalents (TEQs) of PCBs to 2,3,7,8-tetrachlorodibenzo-p-dioxin were 8-15 pg/g in the livers and 13-48 pg/g in the adipose tissues. PCB 126 contributed 85-91% of the total TEQs.

Quantitative analysis of herpesvirus sequences from normal tissue and fibropapillomas of marine turtles with real-time PCR

Quantitative real-time PCR has been used to measure fibropapilloma-associated turtle herpesvirus (FPTHV) pol DNA loads in fibropapillomas, fibromas, and uninvolved tissues of green, loggerhead, and olive ridley turtles from Hawaii, Florida, Costa Rica, Australia, Mexico, and the West Indies. The viral DNA loads from tumors obtained from terminal animals were relatively homogeneous (range 2-20 copies/cell), whereas DNA copy numbers from biopsied tumors and skin of otherwise healthy turtles displayed a wide variation (range 0.001-170 copies/cell) and may reflect the stage of tumor development. FPTHV DNA loads in tumors were 2.5-4.5 logs higher than in uninvolved skin from the same animal regardless of geographic location, further implying a role for FPTHV in the etiology of fibropapillomatosis. Although FPTHV pol sequences amplified from tumors are highly related to each other, single signature amino acid substitutions distinguish the Australia/Hawaii, Mexico/Costa Rica, and Florida/Caribbean groups.

Immune status of free-ranging green turtles with fibropapillomatosis from Hawaii

Cell-mediated and humoral immune status of free-ranging green turtles (Chelonia mydas) in Hawaii (USA) with and without fibropapillornatosis (FP) were assessed. Tumored and non-tumored turtles from Kaneohe Bay (KB) on the island of Oahu and from FP-free areas on the west (Kona/Kohala) coast of the island of Hawaii were sampled from April 1998 through February 1999. Turtles on Oahu were grouped (0-3) for severity of tumors with 0 for absence of tumors, 1 for light, 2 for moderate, and 3 for most severe. Turtles were weighed, straight carapace length measured and the regression slope of weight to straight carapace length compared between groups (KB0, KB1, KB2, KB3, Kona). Blood was assayed for differential white blood cell count, hematocrit, in vitro peripheral blood mononuclear cell (PBMC) proliferation in the presence of concanavalin A (ConA) and phytohaemagglutinin (PHA), and protein electrophoresis. On Oahu, heterophil/lymphocyte ratio increased while eosinophil/monocyte ratio decreased with increasing tumors score. Peripheral blood mononuclear cell proliferation indices for ConA and PHA were significantly lower for turtles with tumor scores 2 and 3. Tumor score 3 turtles (KB3) had significantly lower hematocrit, total protein, alpha 1, alpha 2, and gamma globulins than the other four groups. No significant differences in immune status were seen between non-tumored (or KB1) turtles from Oahu and Hawaii. There was no significant difference between groups in regression slopes of body condition to carapace length. We conclude that turtles with severe FP are imunosuppressed. Furthermore, the lack of significant difference in immune status between non-tumored (and KB1) turtles from Oahu and Kona/Kohala indicates that immunosuppression may not be a prerequisite for development of FP.

Detection of herpesviral sequences in tissues of green turtles with fibropapilloma by polymerase chain reaction

An alpha-herpesvirus has been associated recently with green turtle fibropapilloma (FP). To further clarify the role of this newfound green turtle herpesvirus (GTHV) in the pathogenesis of FP, various normal-appearing tissues and organs (including skin, eye, brain, heart, liver, spleen, intestine, lung, kidney, nerve, gonad, tongue, gall bladder, urinary bladder, thyroid and peripheral blood mononuclear cells (PBMC) from blood) and tumor tissues from 19 green turtles (Chelonia mydas) with FP, and tissues from three green turtles without FP, collected during 1997 to 1999 in the Hawaiian Islands, were tested for GTHV sequences by nested polymerase chain reaction (PCR), using GTHV-specific oligonuclotide primers. GTHV sequences were detected in all tumors (51/51) and most tissues (133/167) of tumored turtles. By contrast, such sequences were undetectable in tissues (0/28) of three non-tumored turtles. Analysis of GTHV sequences detected in different tissues and tumors revealed a low degree of genetic diversity (<1%). The wide distribution of this newfound herpesvirus in tumors and tissues of tumored green turtles and its absence in tissues of non-tumored turtles, argues for an etiologic role in FP.

Assessing humoral and cell-mediated immune response in Hawaiian green turtles, Chelonia mydas

Seven immature green turtles, Chelonia mydas, captured from Kaneohe Bay on the island of Oahu were used to evaluate methods for assessing their immune response. Two turtles each were immunized intramuscularly with egg white lysozyme (EWL) in Freund's complete adjuvant, Gerbu, or ISA-70; a seventh turtle was immunized with saline only and served as a control. Humoral immune response was measured with an indirect enzyme linked immunosorbent assay (ELISA). Cell-mediated immune response was measured using in vitro cell proliferation assays (CPA) using whole blood or peripheral blood mononuclear cells (PBM) cultured with concanavalin A (ConA), phytohaemagglutinin (PHA), or soluble egg EWL antigen. All turtles, except for one immunized with Gerbu and the control, produced a detectable humoral immune response by 6 weeks which persisted for at least 14 weeks after a single immunization. All turtles produced an anamnestic humoral immune response after secondary immunization. Antigen specific cell-mediated immune response in PBM was seen in all turtles either after primary or secondary immunization, but it was not as consistent as humoral immune response; antigen specific cell-mediated immune response in whole blood was rarely seen. Mononuclear cells had significantly higher stimulation indices than whole blood regardless of adjuvant, however, results with whole blood had lower variability. Both Gerbu and ISA-70 appeared to potentiate the cell-mediated immune response when PBM or whole blood were cultured with PHA. This is the first time cell proliferation assays have been compared between whole blood and PBM for reptiles. This is also the first demonstration of antigen specific cell-mediated response in reptiles. Cell proliferation assays allowed us to evaluate the cell-mediated immune response of green turtles. However, CPA may be less reliable than ELISA for detecting antigen specific immune response. Either of the three adjuvants appears suitable to safely elicit a detectable immune response in green turtles.

Identification of a small, naked virus in tumor-like aggregates in cell lines derived from a green turtle, Chelonia mydas, with fibropapillomas

Serial cultivation of cell lines derived from lung, testis, periorbital and tumor tissues of a green turtle (Chelonia mydas) with fibropapillomas resulted in the in vitro formation of tumor-like cell aggregates, ranging in size from 0.5 to 2.0 mm in diameter. Successful induction of tumor-like aggregates was achieved in a cell line derived from lung tissue of healthy green turtles, following inoculation with cell-free media from these tumor-bearing cell lines, suggesting the presence of a transmissible agent. Thin-section electron microscopy of the cell aggregates revealed massive collagen deposits and intranuclear naked viral particles, measuring 50+/-5 nm in diameter. These findings, together with the morphological similarity between these tumor-like cell aggregates and the naturally occurring tumor, suggest a possible association between this novel virus and the disease. Further characterization of this small naked virus will clarify its role in etiology of green turtle fibropapilloma, a life-threatening disease of this endangered marine species.

Comparative pathology and pathogenesis of spontaneous and experimentally induced fibropapillomas of green turtles (Chelonia mydas)

Tumor biopsy samples from 25 Floridian and 15 Hawaiian green turtles (Chelonia mydas) with spontaneous green turtle fibropapillomatosis (GTFP) and from 27 captive-reared green turtles with experimentally induced GTFP were examined microscopically to differentiate the histologic features that result from GTFP pathogenesis and those that result from incidental factors that may vary according to geographic region. Common histologic features for spontaneous and experimentally induced tumors included fibroblast proliferation in the superficial dermis, epidermal acanthosis and hyperkeratosis, epidermal basal cell degeneration with dermal-epidermal cleft formation, spinous layer degeneration with intraepidermal vesicle and pustule formation, and ulceration. Visceral tumors, found in eight of 10 (80%) free-ranging turtles with cutaneous disease that were examined after death, had extensive interstitial fibrous proliferation. The presence of spirorchid trematode eggs and associated foreign body granulomas, common secondary findings within spontaneous tumors, varied by geographic location, and these findings were not observed in experimentally induced tumors. Eosinophilic intranuclear inclusions and intranuclear herpesvirus-associated antigen immunoreactivity were found in 18 of 38 (47%) experimentally induced cutaneous tumors and nine of 119 (7.5%) spontaneous tumors from Floridian but not Hawaiian turtles. The possible involvement of GTFP-associated herpesvirus in the pathogenesis of epidermal degenerative changes and GTFP pathogenesis is discussed.

Relating tumor score to hematology in green turtles with fibropapillomatosis in Hawaii

The relationship between hematologic status and severity of tumor affliction in green turtles (Chelonia mydas) with fibropapillomatosis (FP) was examined. During 1 wk periods in July 1997 and July 1998, we bled 108 free-ranging green turtles from Pala'au (Molokai, Hawaii, USA) where FP is endemic. Blood was analyzed for hematocrit, estimated total solids, total white blood cell (WBC) count and differential WBC count. Each turtle was assigned a subjective tumor score ranging from 0 (no visible external tumors) to 3 (heavily tumored) that indicated the severity of FP. There was a progressive increase in monocytes and a decrease in all other hematologic parameters except heterophils and total numbers of white blood cells as tumor score increased. These data indicate that tumor score can relate to physiologic status of green turtles afflicted with FP, and that tumor score is a useful field monitor of severity of FP in this species.

Establishment and characterization of 13 cell lines from a green turtle (Chelonia mydas) with fibropapillomas

Thirteen cell lines were established and characterized from brain, kidney, lung, spleen, heart, liver, gall bladder, urinary bladder, pancreas, testis, skin, and periorbital and tumor tissues of an immature male green turtle (Chelonia mydas) with fibropapillomas. Cell lines were optimally maintained at 30 degrees C in RPMI 1640 medium supplemented with 10% fetal bovine serum. Propagation of the turtle cell lines was serum dependent, and plating efficiencies ranged from 13 to 37%. The cell lines, which have been subcultivated more than 20 times, had a doubling time of approximately 30 to 36 h. When tested for their sensitivity to several fish viruses, most of the cell lines were susceptible to a rhabdovirus, spring viremia carp virus, but refractory to channel catfish virus (a herpesvirus), infectious pancreatic necrosis virus (a birnavirus), and two other fish rhabdoviruses, infectious hematopoietic necrosis virus and viral hemorrhagic septicemia virus. During in vitro subcultivation, tumor-like cell aggregates appeared in cell lines derived from lungs, testis, and periorbital and tumor tissues, and small, naked intranuclear virus particles were detected by thin-section electron microscopy. These cell lines are currently being used in attempts to isolate the putative etiologic virus of green turtle fibropapilloma.

Morphologic and cytochemical characteristics of blood cells from Hawaiian green turtles

OBJECTIVE

To identify and characterize blood cells from free-ranging Hawaiian green turtles, Chelonia mydas.

SAMPLE POPULATION

26 green turtles from Puako on the island of Hawaii and Kaneohe Bay on the island of Oahu.

PROCEDURE

Blood was examined, using light and electron microscopy and cytochemical stains that included benzidine peroxidase, chloroacetate esterase, alpha naphthyl butyrate esterase, acid phosphatase, Sudan black B, periodic acid-Schiff, and toluidine blue.

RESULTS

6 types of WBC were identified: lymphocytes, monocytes, thrombocytes, heterophils, basophils, and eosinophils (small and large). Morphologic characteristics of mononuclear cells and most granulocytes were similar to those of cells from other reptiles except that green turtles have both large and small eosinophils.

CONCLUSIONS

Our classification of green turtle blood cells clarifies improper nomenclature reported previously and provides a reference for future hematologic studies in this species.

Three closely related herpesviruses are associated with fibropapillomatosis in marine turtles

Green turtle fibropapillomatosis is a neoplastic disease of increasingly significant threat to the survivability of this species. Degenerate PCR primers that target highly conserved regions of genes encoding herpesvirus DNA polymerases were used to amplify a DNA sequence from fibropapillomas and fibromas from Hawaiian and Florida green turtles. All of the tumors tested (n = 23) were found to harbor viral DNA, whereas no viral DNA was detected in skin biopsies from tumor-negative turtles. The tissue distribution of the green turtle herpesvirus appears to be generally limited to tumors where viral DNA was found to accumulate at approximately two to five copies per cell and is occasionally detected, only by PCR, in some tissues normally associated with tumor development. In addition, herpesviral DNA was detected in fibropapillomas from two loggerhead and four olive ridley turtles. Nucleotide sequencing of a 483-bp fragment of the turtle herpesvirus DNA polymerase gene determined that the Florida green turtle and loggerhead turtle sequences are identical and differ from the Hawaiian green turtle sequence by five nucleotide changes, which results in two amino acid substitutions. The olive ridley sequence differs from the Florida and Hawaiian green turtle sequences by 15 and 16 nucleotide changes, respectively, resulting in four amino acid substitutions, three of which are unique to the olive ridley sequence. Our data suggest that these closely related turtle herpesviruses are intimately involved in the genesis of fibropapillomatosis.

Spirorchidiasis and fibropapillomatosis in green turtles from the Hawaiian Islands

Pathologic examination of green turtles (Chelonia mydas) from the Hawaiian Islands (USA) was performed to determine the primary cause of mortality. Lesions were associated with fibropapillomatosis (FP) and/or spirorchidiasis (SP) in 16 of 17 green turtles examined. Gross lesions included moderate to severe emaciation, lobulated fibropapillomas of different size classes, serous atrophy of fat, and edema of subcutaneous tissue and muscle. Anasarca, hydropericardium and pulmonary edema were common findings. The neoplastic lesions observed in the gastrointestinal tract, lungs, liver, and kidneys of 29% of turtles examined were histologically characterized as fibromas. A generalized thickening and hardening of major vessels and thrombosis with partial or complete lumen occlusion were observed in turtles with FP and SP. Histologically, lymphoplasmocytic endarteritis was observed in vessels of turtles with both conditions. Multifocal granulomas were associated with trematode ova in the parenchyma of most organs of all turtles with FP and SP. Spirorchidiasis and FP were considered the primary causes of mortality in the turtles examined. Further studies should focus on the pathogenic interaction of both conditions and their synergism as debilitating and fatal diseases in this threatened species.

Cryptosporidium sp. Infections in Green Turtles, Chelonia mydas, as a Potential Source of Marine Waterborne Oocysts in the Hawaiian Islands

For the first time, Cryptosporidium sp. oocysts were identified in fecal and intestinal samples from free-ranging marine turtles, Chelonia mydas, from the Hawaiian Islands. The oocysts produced positive reactions with commercial test kits recommended for the detection of human-infectious waterborne oocysts of Cryptosporidium parvum.

Detection by ELISA of circulating anti-blood fluke (Carettacola, Hapalotrema, and Learedius) immunoglobulins in Hawaiian green turtles (Chelonia mydas)

An enzyme-linked immunosorbent assay (ELISA) is described utilizing the surface glycocalyx crude antigen of adult blood trematodes Learedius learedi, Hapalotrema dorsopora, and Carettacola hawaiiensis, for the detection of circulating antibodies (Ab) in Hawaiian green turtles (Chelonia mydas) naturally infected with the parasites and with or without green turtle fibropapillomatosis (GTFP). A concentration of 10.0 micrograms/ml of antigen was optimal in terms of test specificity and sensitivity. A direct ELISA with anti-reptilian/amphibian phosphatase-labeled IgG identified C. mydas Ab at a dilution of 1/12,800. Utilizing indirect ELISA, it was possible to detect Ab to blood flukes at a dilution of 1/3,200. The gross lesions and histopathology were typical for cardiovascular spirorchidiasis in C. mydas. No significant relationship was found between the size of turtles and the degree of GTFP severity. Forty-seven of 59 (80%) samples, from 5 sites, gave a positive ELISA reaction; 6 of the 47 (13%) specimens gave significantly (P < 0.001) higher absorbance values, with 5 from the same location. All 12 (20%) ELISA-negative turtles originated from 1 site, and the absorbance values of the 41 animals from this location were significantly lower (P < 0.015) when compared with the other 4 sites. The proposed assay is fast, has the feature of visual scoring, and can be used for determination of exposure of C. mydas to the spirorchid trematodes.

Trans-Pacific migrations of the loggerhead turtle (Caretta caretta) demonstrated with mitochondrial DNA markers

Juvenile loggerhead turtles (Caretta caretta) have recently been documented in the vicinity of Baja California and thousands of these animals have been captured in oceanic fisheries of the North Pacific. The presence of loggerhead turtles in the central and eastern North Pacific is a prominent enigma in marine turtle distribution because the nearest documented nesting concentrations for this species are in Australia and Japan, over 10,000 km from Baja California. To determine the origin of the Baja California feeding aggregate and North Pacific fishery mortalities, samples from nesting areas and pelagic feeding aggregates were compared with genetic markers derived from mtDNA control region sequences. Overall, 57 of 60 pelagic samples (95%) match haplotypes seen only in Japanese nesting areas, implicating Japan as the primary source of turtles in the North Pacific Current and around Baja California. Australian nesting colonies may contribute the remaining 5% of these pelagic feeding aggregates. Juvenile loggerhead turtles apparently traverse the entire Pacific Ocean, approximately one-third of the planet, in the course of developmental migrations, but mortality in high-seas fisheries raises concern over the future of this migratory population.

Radiation-induced lung injury using a pig model. Evaluation by high-resolution computed tomography

RATIONALE AND OBJECTIVES

To assess the early phase of radiation-induced lung injury using high-resolution computed tomography (CT) under experimental conditions and to perform precise CT-pathologic correlation.

METHODS

Five Yorkshire pigs received a single dose of 12.5 Gy to the right lower lung. Computed tomographic images were obtained at 2-week intervals. The animals were killed after follow-up periods of 4-16 weeks. The lungs were removed, inflated, fixed, dried, and sliced corresponding to the CT sections. Computed tomography, specimen radiography, and histologic findings were correlated.

RESULTS

Various CT findings were observed during the first 16 weeks, including ground-glass opacity, discrete consolidation, patchy consolidation, thickened interlobular septum, and bronchovascular bundle. Ground-glass opacity was associated with thickened alveolar wall and scattered tiny fibrotic foci. Thickened interlobular septum and bronchovascular bundle were the results of fibrosis adjacent to these structures. Discrete consolidation correlated with intraalveolar edema with hemorrhage and infiltration of inflammatory cells.

CONCLUSIONS

High-resolution CT correlated well with pathology of the lung due to radiation injury as verified by precise radiologic-pathologic correlation.

Bleomycin-induced fibrosis in pigs: evaluation with CT

PURPOSE

To establish an animal model for use in evaluation of early morphologic changes of pulmonary fibrosis by means of precise correlation of findings at thin-section computed tomography (CT) and pathologic findings.

MATERIALS AND METHODS

Bleomycin (1.0-2.5 U per kilogram of body weight) was delivered selectively into the left lower lobe bronchus via balloon catheter in five Yorkshire pigs. Sequential CT examinations were performed at regular intervals. The animals were killed at follow-up of 5 days to 4 weeks. At autopsy, the lungs were removed, inflated, fixed and dried, and subsequently sliced into sections that corresponded to the CT sections. The fixed lungs were examined with thin-section CT, radiography, and histologic studies.

RESULTS

There was good correlation between pathologic findings at CT and specimen radiography. Histologic study revealed signs of pneumonitis and developing fibrosis.

CONCLUSIONS

This disease model is suitable for radiologic and pathologic evaluation of interstitial fibrosis. CT was sensitive in detection of bleomycin-induced abnormalities.

Evaluation of Hawaiian green turtles (Chelonia mydas) for potential pathogens associated with fibropapillomas

Thirty-two juvenile green turtles (Chelonia mydas) were captured alive in Kaneohe Bay, Island of Oahu, Hawaii, during September 1991. Ten of the turtles sampled were afflicted with green turtle fibropapillomatosis (GTFP) in varying degrees of severity. Virus isolation attempts were negative in all individuals. Using nasopharyngeal and cloacal swabs, we isolated 28 Gram negative bacteria, five Gram positive cocci, Bacillus spp., and diphtheroids. The most common isolates included Pseudomonas fluorescens (68%), P. putrefaciens (66%), Vibrio alginolyticus (50%), non-hemolytic Streptococcus (50%), V. damsela (47%), and V. fluvialis (47%). Chlamydial antigen was detected in four of the turtles sampled. The primary lesions in animals with GTFP were hyperplasia of squamous epithelial cells and mesodermal proliferation with a marked degree of orthokeratotic hyperkeratosis. Mites, leeches, and other organisms were associated with the surface of papilloma lesions. The etiologic agent of GTFP was not isolated.

Experimental pulmonary infarction in a pig model

RATIONALE AND OBJECTIVES

The authors sought to develop a reliable animal model for experimental pulmonary infarction, to evaluate it with radiologic-pathologic correlation, and to determine the use of high-resolution computed tomography (HRCT) in monitoring parenchymal lung damage due to infarction.

METHODS

Selective left lower lobe pulmonary artery occlusion was performed in seven Yorkshire pigs with transcatheter silicone elastomer injection. After occlusion, 99m technetium (99mTc) macroaggregated albumin perfusion lung scans and sequential in vivo HRCT lung scans were obtained from days 0 to 46. The in vivo radiologic findings were correlated with specimen radiography, specimen HRCT, and histologic findings.

RESULTS

A complete and permanent arterial occlusion was achieved, involving up to three orders of branching distal to the catheter. An anatomically defined perfusion defect was seen on 99mTc lung scans corresponding to the occluded area. HRCT changes consisted of confluent densities progressing to mixed alveolar and interstitial opacities within the first week after embolization. In the follow-up period, marked parenchymal clearing was observed. In all cases after pulmonary artery occlusion, the histologic findings were characteristic of pulmonary infarction and demonstrated alveolar edema, hemorrhage, limited alveolar wall damage, and septal thickening followed by residual fibrosis.

CONCLUSION

Using this model, it is feasible to produce pulmonary infarction in the pig which may potentially be useful to study the pathophysiologic and radiologic changes of pulmonary infarction.

Carettacola hawaiiensis n. sp. (Trematoda: Spirorchidae) from the green turtle, Chelonia mydas, in Hawaii

Carettacola hawaiiensis n. sp. (Trematoda: Spirorchidae) is described from the hepatic vessels of the green turtle, Chelonia mydas (L.), in Hawaii. The new species differs from any previously described species of Carettacola in size, placement of vitellaria, and shape and placement of Laurer's canal. The genus Haemoxenicon Martin and Bamberger, 1952, becomes a synonym of Carettacola Manter and Larson, 1950. Haemoxenicon stunkardi Martin and Bamberger, 1952, is transferred to the genus Carettacola Manter and Larson, 1950, and becomes Carettacola stunkardi n. comb. An emended generic diagnosis for Carettacola is given along with a key to the species.

Immunogenetic and immunologic studies of differentiated thyroid cancer

The authors have studied in detail human leukocyte antigen (HLA) association in 87 Hungarian patients with thyroid epithelial carcinoma. The authors also examined in a small group of patients, five parameters of cell-mediated immunity and related them to HLA as well as to lymphocytic infiltration of the tumor/normal tissue interface. HLA-DR1 was significantly associated with thyroid carcinoma; the strongest association was in patients with follicular histologic features and DR1 homozygotes were not at greater risk for thyroid cancer. The HLA-DR3 was nonsignificantly increased in patients with papillary or mixed histologic features. The HLA-DR1, 3 heterozygotes were highly associated with follicular carcinoma, carried no risk for papillary carcinoma, and an intermediate risk for tumors with mixed histologic features. Because of the small proportion of DR1, 3 heterozygotes in the follicular and mixed histologic group, its predictive value at the population level was low. Better predictive potential was shown for the phenotype DR1 and/or DR3. Neither metastatic disease nor age at diagnosis (less than 45 years) could be related to HLA phenotypes. Patients in all histologic variants showed some measure of cell-mediated immunity compared to controls. Patients with papillary carcinoma showed an overall better response than those with tumors with follicular or mixed histology. The HLA-DR could not be related to cell-mediated immune response. Patients with papillary carcinoma with a good cell-mediated immune response occurred with much lower infiltration of the tumor boundary with lymphocyte whereas the follicular carcinoma less cell-mediated immunity was associated with dense lymphocytic infiltration, suggesting the biological relevance of lymphocytic infiltration may be different for the two histologic variants.

Interaction of IgG heavy-chain allotypes (Gm) and HLA in conferring susceptibility to thyroid carcinoma

We have recently reported an increase in HLA-DR1 in 52 patients with thyroid epithelial cancer from Eastern Hungary (Juhasz et al., 1986). We have now investigated the association of IgG heavy chain markers (Gm) in 50 patients with this disease and explored possible interaction between Gm and HLA in modifying the risk for thyroid cancer. No Gm phenotype showed significant increases in the patients compared to 168 local controls. When both Gm and HLA, however, were considered, a marked heterogeneity in risk was noted. The odds ratio for DR1+fb+ homozygotes was 37.5, for DR1+fb- individuals 6.0 and for DR1-fb+ individuals 2.6 (DR1-fb- = 1.0). Thus Gm and HLA interact to enhance greatly the risk of thyroid cancer.