Low affinity E-rosette formation by the human K cell.

Human T lymphocytes were separated into two subsets on the basis of relative affinity for sheep red blood cells (E), and these T cell fractions were examined for cytotoxic reactivity against antibody-sensitized Change liver cells (ADCC). High affinity E-rosette-forming cells (E-RFC) (55 +/- 6% of peripheral blood mononuclear cells), capable of rosette formation despite elevated temperatures of incubation (29 degrees C) and a limited concentration of E, contained few antibody-dependent cytotoxic cells (K cells). In contrast, low affinity E-RFC (23+/-7% of mononuclear cell suspensions) requiring cool temperatures of incubation (4 degrees C) and an excess of E to form rosettes, were highly enriched for ADCC activity. The majority of K cells exhibited low affinity interactions with E. T cells in thymus, tonsil, and lymph node formed high affinity E-rosettes and exhibited little reactivity in ADCC. Only peripheral blood and spleen contained easily identified low affinity E-RFC and anti-body-dependent cytotoxic cells. The proportion of low affinity E-RFC in the peripheral blood of normal subjects correlated closely with reactivity in ADCC, making it possible to predict cytotoxic potential for the E-rosette pattern. These data indicate that the human K cell may belong to a previously unappreciated but functionally important subset of thymic dependent mononuclear cells.     

The effects of temperature on metabolic rates of different life stages of Calanus glacialis in the Barents Sea

Summary The effects of temperature on rates of respiration, excretion and gut evacuation were examined for copepodite stages and adult female Calanus glacialis collected in areas close to the ice-edge during the arctic summer in the Barents Sea. The various life history stages responded differently to acute temperature changes above the in situ temperature (ca.-1.7°C). Respiration rates of early copepodite stages (C I to C IV) were very variable whereas excretion rates declined with increasing temperature in the range from-1.7°C to +5°C. Rate of oxygen consumption of adult females were independent of temperature between-1.7° and +5°C, but increased as temperature increased from +5° to 10°C. Rates of excretion of copepodite stage V and adult females were independent of temperature in the range from-1.7° to +2°C, whereas excretion of copepodite stages III and IV was negatively related to temperature in the range from-1.7° to +5°C. In C IV, C V and adult females the instantaneous rate of gut evacuation increased with increasing temperature. The different response patterns of metabolic rates of small copepodite stages, copepodite stage V and adult females C. glacialis to acute temperature changes suggest that the capacity for adjustment of ammonia excretion is better developed in C V's and adult females than in the younger life stages.     

The effect of environmental variation on the reproductive development time and output of the high-shore rockpool copepod Tigriopus brevicornis

The extreme environmental changes observed in high-shore rockpools occupied by Tigriopus brevicornis, provide a significant physiological challenge that may have implications for the energetics and hence the life history characteristics of this species. The present study was designed to assess the effect of this environmental variation on the reproductive development time and output of T. brevicornis in terms of duration of the various stages in ovary and egg sac development and maturation as well as naupliar development time to the first copepodite stage and total numbers of copepodites produced.There was a significant difference in reproductive development time and output in the three test salinities with only successful development to copepodite I stage seen in normal seawater (35 psu). There was also a successful release of nauplii seen at the low salinity (5 psu), but no subsequent survival to the copepodite I stage, whilst there was not even a development of egg sacs in the high salinity test medium (70 psu). There was also a significant difference in reproductive development times in the three test temperatures with fastest ovary development in the high temperature (23 °C) and slowest development time in the lowest temperature (5 °C). However, it should be noted that the highest number of nauplii produced was actually in the mid temperature (12 °C), not the high temperature. Exposure to hypoxic and anoxic conditions had a significantly detrimental effect on reproductive development with slower development time through the reproductive stages and no individuals surviving to copepodite stage I from the hypoxic and anoxic test conditions, but good development from the normoxic conditions.The present study indicates that animals living in high-shore rockpools may incur a considerable energetic cost, due to the environmental changes that are characteristic of this habitat and the importance of resource allocation in these different physiological conditions is paramount to the species' survival.     

Results of the determination of serum markers in patients with malignant melanoma

Although there is no routine procedure for determination of serum markers in patients with malignant melanoma (MM), some markers are being studied as potentially useful prognostic tools. Serum lactate dehydrogenase (LDH), protein S-100B, melanoma-inhibiting activity (MIA) and tyrosinase may correlate with melanoma progression. In this study, the results of determination of S100 protein, LDH, MIA and tyrosinase in the serum of 50 patients with MM (stages I-IV) were determined. The increased values of MIA were found in 26% patients in stage I, while in 50% patients in stage IV Increased S-100 protein was found in 13% patients in stage I while in 50% patients in stage IV. The increased values of LDH were found in 26% patients in stage I, while in 25% patients in stage IV. The positive serum tyrosinase was noticed in 17.3% patients in stage II, while in 25% patients in stage IV. The obtained results have revealed no significant differences between the groups in higher and lower stages of the disease, indicating that blood markers are not reliable prognostic factors for MM progression.     

Developmental genetics of a temperature-sensitive RNA polymerase II mutation in Drosophila melanogaster

Summary Purified RNA polymerase II (RNA nucleotidyl-transferase; EC 2.7.7.6) extracted from flies possessing lesions in the Ultrabithorax-like (Ubl) locus of Drosophila melanogaster has altered activity in vitro (Greenleaf et al. 1979, 1980; Coulter and Greenleaf 1982). This strongly suggests that the Ubl locus encodes a subunit of RNA polymerase II. Ethyl methanesulfonate was used to induce a temperature-sensitive mutation in this locus. Flies either homozygous or hemizygous for this new X–linked mutation (Ubl ^ts) display viability comparable to that of wild-type flies at 22° C but are lethal at 29° C. The temperature-sensitive period for Ubl ^ts flies is between gastrulation (6 h, 29° C) and pupation (9–10 days, 22° C). Zygotes shifted from 22° C to 29° C die at either the late embryonic or first larval instar stage while temperature shifts of second and third instar larvae result in the lethal phase occurring at the pupal stage. Most pupae shifted from 22° C to 29° C undergo metamorphosis and eclose as adults. Adults are viable if placed at 29° C; however, all females and some males become sterile if maintained at this temperature.Somatic recombination was used to induce clones homozygous for a null allele of Ubl at different stages of development. Clones of this null allele appear to be cell lethal indicating that the Ubl ⁺ gene product is required at all stages of development. The viability of Ubl ^ts pupae and adults at 29° C may result from only a partial reduction in activity caused by the mutation at this nonpermissive temperature.     

Bionomics and population growth statistics of apterous virginoparae of woolly apple aphid, Eriosoma lanigerum, at constant temperatures

Development, survival, reproduction and population growth statistics of apterous virginoparae of woolly apple aphid, Eriosoma lanigerum (Hausmann) (Hemiptera: Aphididae) at constant temperatures of 10, 13, 15, 20, 25, 30 and 32°C are reported. The developmental times of all life stages were inversely related to temperature ranging from 10 to 30°C. Span of total development (time from birth to adulthood) decreased from 57.8 days at 10°C to 11.7 days at 30°C and increased to 16.8 days at 32°C. A good linear model fit (R²>0.96) between developmental rate and temperature in the range 10–25°C was observed for all life stages. The lower developmental threshold was estimated at 5.8°C for instar I, 4.8°C for instar II, 4.9° for instar III and 4.4°C for instar IV. The lower temperature threshold for total development was estimated at 5.2°C. The upper developmental limit was found to be 32°C. Mean degree-day accumulations required for completion of instars I, II, III, IV and total development were: 125.6, 51.0, 47.7, 50.7 and 267.6, respectively. Fecundity, larviposition period and adult longevity were reduced with increasing temperature. Net reproductive rate was greatest at 15°C whereas intrinsic rate of increase peaked at 25°C. Optimal performance, as measured by fecundity, survival and intrinsic rate of increase, ocurred in the range 13–25°C.     

Purification and partial characterization of two extracellular keratinases of Scopulariopsis brevicaulis

Two extracellular keratinases of Scopulariopsis brevicaulis were purified and partially characterized. The enzymes were isolated by the techniques of gel filtration chromatography and sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). These keratinases (K I & K II) were purified approximately 33 and 29 fold, respectively. SDS-PAGE of the products of gel filtration chromatography (K I & II) produced only one band each, suggesting homogeneity. The optimum pH for both keratinases was 7.8, while the optimum temperatures were 40°C (K I) and 35°C (K II). Estimated molecular weights were 40–45 KDa and 24–29 KDa for K I & K II respectively. Both keratinases were inhibited by phenylmethylsulfonyl fluoride which suggests a serine residue at or near an active site.     

Fine structure of flight muscles in different Notch mutants of Drosophila melanogaster reared at different temperatures

Summary The fine structure of the indirect flight muscles was studied by electron microscopy in the following Notch locus mutants of Drosophila melanogaster reared at 18° C or 29° C for 6 days after eclosion: Ax ¹⁶¹⁷²/Ax¹⁶¹⁷², Ax²⁸/ Ax²⁸, l(1)N^ts1/l(1)N^ts1,l(1)N^ts1/Y and in wild-type controls. The flies were raised up to eclosion at 25° C or 18° C. It was observed that the l(1)N^ts1 flies gradually became flightless within a few days if reared at 29° C as adults, and gross changes in the fine structure of the flight muscles were also observed in flies of this genotype. Peripheral myofilaments of myofibrils were disarranged and the mitochondria diminutive. At 18° C the flight muscles remained normal. In all of the Abruptex (Ax) combinations the flight muscles remained similar to the wild-type controls at both 18° C and 29° C, i.e. they were normal. The results suggest that the Notch gene is active in adult flies in addition to its activity during embryonic, larval and pupal stages, and is directly or indirectly involved in the adult development of the muscle tissue.     

Larval and early juvenile development of Lithodes santolla (Molina, 1782) (Decapoda: Anomura: Lithodidae) reared at different temperatures in the laboratory

The southern king crab, Lithodes santolla Molina, is distributed in cold-temperate and subantarctic waters ranging from the southeastern Pacific island of Chiloé (Chile) and the deep Atlantic waters off Uruguay, south to the Beagle Channel (Tierra del Fuego, Argentina/Chile). Recent investigations have shown that its complete larval development from hatching to metamorphosis, comprising three zoeal stages and a megalopa, is fully lecithotrophic, i.e. independent of food. In the present study, larvae were individually reared in the laboratory at seven constant temperatures ranging from 1 to 18 °C, and rates of survival and development through successive larval and early juvenile stages were monitored throughout a period of 1 year. The highest temperature (18 °C) caused complete mortality within 1 week; only a single individual moulted under this condition, 2 days after hatching, to the second zoeal stage, while all other larvae died later in the zoea I stage. At the coldest condition (1 °C), 71% of the larvae reached the zoea III stage, but none of these moulted successfully to a megalopa. A temperature of 3 °C allowed for some survival to the megalopa stage (17-33% in larvae obtained from two different females), but only a single individual passed successfully, 129 days after hatching, through metamorphosis to the first juvenile crab instar. At all other experimental conditions (6, 9, 12 and 15 °C), survival through metamorphosis varied among temperatures and two hatches from 29% to 90% without showing a consistent trend. The time of nonfeeding development from hatching to metamorphosis lasted, on average, from 19 days at 15 °C to 65 days at 6 °C. The relationship between the time of development through individual larval or juvenile stages (D) and temperature (T) was described as a power function (D=aT^b, or log[D]=log[a]blog[T]). The same model was also used to describe the temperature dependence of cumulative periods of development from hatching to later larval or juvenile stages. One year after hatching, the 7th (6 °C) to 9th (15 °C) crab instar was reached. Under natural temperature conditions in the region of origin of our material (Beagle Channel, Argentina), L. santolla should reach metamorphosis in October-December, i.e. ca. 2 months after hatching (taking place in winter and early spring). Within 1 year from hatching, the crabs should grow approximately to juvenile instars VII-VIII. Our results indicate that the early life-history stages of L. santolla tolerate moderate cold stress as well as planktonic food-limitation in winter, implying that this species is well adapted to subantarctic environments with low temperatures and a short seasonal plankton production.     

Direct endolymphatic instillation (ELI) of BCG-Tumor cell mixture

Summary A method of active immunization by direct Endolymphatic Instillation (ELI) of a mixture of BCG and Autologous Irradiated Tumor Cells (AITC) is described. ELI was performed in 36 patients with advanced breast cancer, melanoma and some other solid tumors. The procedure was well tolerated and was not associated with any untoward systemic side effects other than those often encountered in conventional BCG immunotherapy. Exposure of patients to AITC by the direct endolymphatic route proved to be superior to immunization by the intradermal route as judged by the subsequent induction of cutaneous Delayed Hypersensitivity Reaction (DHR) toward AITC. When employed as the first immunization attempt ELI was effective in 5 of 6 patients. It led to invigoration of preexisting weak DHR in 6 of 8 patients. In 15 of 22 patients conversion to a strongly positive cutaneous DHR to AITC was achieved by ELI, where previous attempts of immunization by the intradermal route had failed to elicit a positive response. Acquisition of positive cutaneous response to AITC following ELI was found to correlate with favourable prognosis in terms of longer median survival. The effect of ELI was particularly notable with respect to enhancement of in vitro lymphocyte stimulation by PPD antigen, but was not followed by increased reactivity of other in vitro parameters of cell-mediated immunity such as peripheral lymphocyte count, proportion of E-rosette forming cells, and PHA lymphocyte stimulation.Abbreviations used: ELI — Endolymphatic Instillation; AITC — Autologous Irradiated Tumor Cells; BCG — Bacillus Calmette-Guérin; DHR — Delayed Hypersensitivity Reaction; PPD — Purified Protein Derivative (tuberculin); PHA — Phytohemagglutinin; SI — Stimulation Index; E-RFC — E-Rosette Forming Cells; PBL — Peripheral Blood Lymphocytes.     

Effects of incubation temperature on growth and development of embryos ofAlligator mississippiensis

Summary Eggs ofAlligator mississippiensis were incubated at 30 °C and 33 °C throughout incubation up to hatching. Every four days several eggs were opened and the albumen, yolk and extra-embryonic fluids removed and weighed. The embryo was removed and fixed prior to being staged, weighted and measured for various morphometric criteria. Development at 33 °C was accelerated compared with 30 °C in terms of yolk and albumen utilization and embryo growth. Significant losses in yolk mass did not occur until stage 22 at 33 °C but occurred at stage 18 at 30 °C. Different patterns in growth were observed in embryos at the two temperatures at similar morphological stages: between stages 18 and 22 embryos at 33 °C were smaller (in mass and length) compared with embryos at 30 °C despite being morphologically similar. The differences in growth and physiology between embryos at 30 °C (females) and 33 °C (males) were dependent on incubation temperature but not sex. Incubation at 33 °C accelerated both growth and development inAlligator; initially morphogenesis was accelerated by the higher temperature but later, growth rate was accelerated.     

Changes in log quality at different decay stages in an alpine forest

倒木是高寒森林生态系统重要的碳(C)库和养分库,其不同分解阶段的质量变化,是认识倒木分解过程中C和养分释放的重要基础。以一个分解序列的岷江冷杉(Abies faxoniana)倒木为研究对象,研究了心材、边材和树皮在5个分解阶段的C:N:P化学计量特征,以及木质素和纤维素含量动态。结果显示:I至III分解阶段,随着分解程度加深,树皮C含量升高,而心材和边材C含量降低,从IV分解阶段开始倒木各组分C含量均开始显著降低。除III分解阶段的心材外,倒木各组分N含量总体表现为随着分解程度加深而增加的趋势,除边材N含量在V分解阶段时显著升高外,其余组分均未达到显著性水平。心材和树皮P含量表现为先降后升的变化趋势,最小值分别出现在III和II分解阶段;边材P含量表现为随着分解程度加深而增加。在同一分解阶段,树皮相对于边材和心材均具有最低的C:N:P化学计量比,易分解比例Fm也表明树皮更易于分解。边材在I和II分解阶段的C:N:P化学计量比最高,心材在III到V分解阶段C:N:P化学计量比最高。心材C:P、树皮和边材的C:N和C:P临界值与N和P的初始值成反比。纤维素含量随着倒木分解而降低,不同分解阶段的纤维素含量表现为:心材>边材>树皮;但木质素含量随着分解程度加深而增加,表现为:树皮>边材>心材;倒木3个组分纤维素含量下降均快于木质素,此外,IV和V分解阶段的树皮木质素与纤维素比值显著增高,且一直处于较高水平。统计分析结果表明:倒木N含量显著影响不同分解阶段木质素和纤维素分解。由生态化学计量学理论推测:树皮分解前期易受N限制,整个分解阶段均易受P限制,心材和边材在整个分解阶段均易受N和P限制。     

Cooling of pacu (Piaractus mesopotamicus) embryos at various stages of development for 6 or 10 hours

The objective of this research was to verify the effects of cooling embryos of pacu, Piaractus mesopotamicus, in four stages of development during two stocking periods. The stages of embryo development were at: blastoderm, ∼64 cells—1.4 h after fertilization (haf); 25% of the epiboly movement—5.2 haf; blastoporous closing—8.0 haf; and optical vesicle appearing—13.3 haf. Embryos were exposed to a cryoprotectant solution containing methanol (10%) and sucrose (0.5 M). Thereafter, embryos were submitted to a cooling curve until they reached −8 °C, and then kept cooled for 6 or 10 h. In addition, for each stage of embryonic development, a control group with uncooled embryos was used to compare hatching rates. The total number of larvae from the first two stages of ontogenetic development (1.4 and 5.2 haf) was lower compared to the other stages (0.0 and 8.0 haf). There was no significant difference between stages 8.0 and 13.3 haf for the total number of larvae (49.9 ± 6.7% and 55.2 ± 6.7%, respectively). Embryo diameter varied according to embryonic stage, providing evidence of differences in membrane permeability. There was a negative correlation between embryo diameter and the total number of larvae (r = −0.372). In conclusion, use of embryonic stages 8.0 and 13.3 haf were recommended for maintaining cooled pacu embryos at −8 °C for 6 or 10 h.     

Prognostic value of assays for circulating immune complexes and natural cytotoxicity in malignant skin melanoma (stages I and II)

Summary The aim of the present study was to determine the possible prognostic value of immune complex determinations and estimations of natural cytotoxicity in melanoma patients. Circulating immune complexes were assayed in 46 patients suffering from malignant skin melanoma (stages I and II) by a direct complement consumption (CC) test, a polyethylene glycol (PEG) precipitation CC assay and a solid-phase Clq-protein A-binding assay. The presence of both IgG- and IgM-containing complexes in IC-positive melanoma sera was confirmed by an Ig-class-specific precipitation-immunoradiometric assay. Results based on this assay and reduction-alkylation data indicated that IgM-containing IC were responsible for a major part of the IC activity recorded in the CC-assays.Soluble immune complex activity, as measured by the direct CC test and the PEG-CC assay, correlated with relapse, whereas the expected inverse relationship between natural cytotoxicity and recurrence was not established. This finding may be explained by the apparent predominance of IgM-containing immune complexes in patients subsequently showing relapse.     

Temperature-dependent activity in early life stages of the stone crab Paralomis granulosa (Decapoda, Anomura, Lithodidae): A role for ionic and magnesium regulation?

Marine brachyuran and anomuran crustaceans are completely absent from the extremely cold (− 1.8 °C) Antarctic continental shelf, but caridean shrimps are abundant. This has at least partly been attributed to low capacities for magnesium excretion in brachyuran and anomuran lithodid crabs ([Mg²⁺]_HL = 20-50 mmol L^− 1) compared to caridean shrimp species ([Mg²⁺]_HL = 5-12 mmol L^− 1). Magnesium has an anaesthetizing effect and reduces cold tolerance and activity of adult brachyuran crabs. We investigated whether the capacity for magnesium regulation is a factor that influences temperature-dependent activity of early ontogenetic stages of the Sub-Antarctic lithodid crab Paralomis granulosa. Ion composition (Na⁺, Mg²⁺, Ca²⁺, Cl⁻, SO₄²⁻) was measured in haemolymph withdrawn from larval stages, the first and second juvenile instars (crabs I and II) and adult males and females. Magnesium excretion improved during ontogeny, but haemolymph sulphate concentration was lowest in the zoeal stages. Neither haemolymph magnesium concentrations nor Ca²⁺:Mg²⁺ ratios paralleled activity levels of the life stages. Long-term (3 week) cold exposure of crab I to 1 °C caused a significant rise of haemolymph sulphate concentration and a decrease in magnesium and calcium concentrations compared to control temperature (9 °C). Spontaneous swimming activity of the zoeal stages was determined at 1, 4 and 9 °C in natural sea water (NSW, [Mg²⁺] = 51 mmol L^− 1) and in sea water enriched with magnesium (NSW + Mg²⁺, [Mg²⁺] = 97 mmol L^− 1). It declined significantly with temperature but only insignificantly with increased magnesium concentration. Spontaneous velocities were low, reflecting the demersal life style of the zoeae. Heart rate, scaphognathite beat rate and forced swimming activity (maxilliped beat rate, zoea I) or antennule beat rate (crab I) were investigated in response to acute temperature change (9, 6, 3, 1, − 1 °C) in NSW or NSW + Mg²⁺. High magnesium concentration reduced heart rates in both stages. The temperature-frequency curve of the maxilliped beat (maximum: 9.6 beats s^− 1 at 6.6 °C in NSW) of zoea I was depressed and shifted towards warmer temperatures by 2 °C in NSW + Mg²⁺, but antennule beat rate of crab I was not affected. Magnesium may therefore influence cold tolerance of highly active larvae, but it remains questionable whether the slow-moving lithodid crabs with demersal larvae would benefit from an enhanced magnesium excretion in nature.     

Influence of thymosin on E-rosette formation of lymphoid cells in leukemic and nonleukemic children.

The influence of two thymosin and two spleen control preparations on the E-rosette formation of peripheral blood lymphocytes and leukemic cells from non-leukemic children with depressed T cell values and leukemic children was investigated. Both thymosin preparations but also one of the control preparations induced a significant increase in the mean percentage of E-rosette forming PBL in the non-leukemic children with depressed T cell values. Thymosin and spleen preparations, however, did not convert the non-erythrocyte binding blasts to erythrocyte binding cells in either common or pre-T-ALL.     

Larval development ofMacrophthalmus erato De Man, 1887 (Brachyura ocypodidae)

The zoeal and megalopal stage ofMacrophthalmus erato were obtained under laboratory conditions and are described and figured. Five zoeal and one megalopal stages were reared at 25; salinity and temperature of 29°C. Their features are compared with those of known species of the genus.     

Biology of Ixodes Rubicundus Ticks under Laboratory Conditions: Observations on Oviposition and Egg Development

Observations on oviposition and egg development of Ixodes rubicundus were made under laboratory conditions. Engorged females were exposed to temperatures in the range 10–25°C and relative humidities (RHs) of 33 and 93%. The pre-oviposition period, oviposition period, incubation period, conversion efficiency index (CEI) values and fecundity were determined. The mean pre-oviposition period varied from 13.3 days (temperature 25°C and RH 33%) to 68.3 days (temperature 10°C and RH 93%). Oviposition extended from a mean of 39 days (temperature 25°C and RH 93%) to 201.7 days (temperature 10°C and RH 93%). The developmental zero temperature for the pre-oviposition period was 9.2°C. The mean total number of eggs produced by engorged I. rubicundus females varied from 2045.7 (temperature 10°C and RH 93%) to 3777.7 (temperature 20°C and RH 93%). Both female mass and RH significantly (p < 0.01) influenced the number of eggs produced. CEI values varied between 43.1–54.4% (RH 93%) and 34.1–42.5% (RH 33%). At 93% RH females produced between 14.2 and 17.7 eggs per mg body mass compared to the 13.2–14.6 eggs per mg body mass at 33% RH. The shortest mean incubation period recorded was 164.3 days (temperature 25°C and RH 93%). The developmental zero temperature for incubation was 6.5°C. Both the pre-oviposition and oviposition periods of I. rubicundus are more extended compared to other species of the genus. Ixodes rubicundus produces a large number of small eggs compared to other prostriate ticks.