Exploring novel immunotherapy biomarker candidates induced by cancer deformation

Triple-negative breast cancer (TNBC) demands urgent attention for the development of effective treatment strategies due to its aggressiveness and limited therapeutic options [1]. This research is primarily focused on identifying new biomarkers vital for immunotherapy, with the aim of developing tailored treatments specifically for TNBC, such as those targeting the PD-1/PD-L1 pathway. To achieve this, the study places a strong emphasis on investigating Ig genes, a characteristic of immune checkpoint inhibitors, particularly genes expressing Ig-like domains with altered expression levels induced by "cancer deformation," a condition associated with cancer malignancy. Human cells can express approximately 800 Ig family genes, yet only a few Ig genes, including PD-1 and PD-L1, have been developed into immunotherapy drugs thus far. Therefore, we investigated the Ig genes that were either upregulated or downregulated by the artificial metastatic environment in TNBC cell line. As a result, we confirmed the upregulation of approximately 13 Ig genes and validated them using qPCR. In summary, our study proposes an approach for identifying new biomarkers applicable to future immunotherapies aimed at addressing challenging cases of TNBC where conventional treatments fall short.

Human Motor Neurons Elicit Pathological Hallmarks of ALS and Reveal Potential Biomarkers of the Disease in Response to Prolonged IFNγ Exposure

Amyotrophic lateral sclerosis (ALS) is a debilitating neurodegenerative disorder marked by progressive motor neuron degeneration and muscle denervation. A recent transcriptomic study integrating a wide range of human ALS samples revealed that the upregulation of p53, a downstream target of inflammatory stress, is commonly detected in familial and sporadic ALS cases by a mechanism linked to a transactive response DNA-binding protein 43 (TDP-43) dysfunction. In this study, we show that prolonged interferon-gamma (IFNγ) treatment of human induced pluripotent stem cell-derived spinal motor neurons results in a severe cytoplasmic aggregation of TDP-43. TDP-43 dysfunction resulting from either IFNγ exposure or an ALS-associated TDP-43 mutation was associated with the activation of the p53 pathway. This was accompanied by the hyperactivation of neuronal firing, followed by the complete loss of their electrophysiological function. Through a comparative single-cell transcriptome analysis, we have identified significant alterations in ALS-associated genes in motor neurons exposed to IFNγ, implicating their direct involvement in ALS pathology. Interestingly, IFNγ was found to induce significant levels of programmed death-ligand 1 (PD-L1) expression in motor neurons without affecting the levels of any other immune checkpoint proteins. This finding suggests a potential role of excessive PD-L1 expression in ALS development, given that PD-L1 was recently reported to impair neuronal firing ability in mice. Our findings suggest that exposing motor neurons to IFNγ could directly derive ALS pathogenesis, even without the presence of the inherent genetic mutation or functional glia component. Furthermore, this study provides a comprehensive list of potential candidate genes for future immunotherapeutic targets with which to treat sporadic forms of ALS, which account for 90% of all reported cases.

Ultra-fast genetically encoded sensor for precise real-time monitoring of physiological and pathophysiological peroxide dynamics

Hydrogen Peroxide (H2O2) is a central oxidant in redox biology due to its pleiotropic role in physiology and pathology. However, real-time monitoring of H2O2 in living cells and tissues remains a challenge. We address this gap with the development of an optogenetic hydRogen perOxide Sensor (oROS), leveraging the bacterial peroxide binding domain OxyR. Previously engineered OxyR-based fluorescent peroxide sensors lack the necessary sensitivity and response speed for effective real-time monitoring. By structurally redesigning the fusion of Escherichia coli (E. coli) ecOxyR with a circularly permutated green fluorescent protein (cpGFP), we created a novel, green-fluorescent peroxide sensor oROS-G. oROS-G exhibits high sensitivity and fast on-and-off kinetics, ideal for monitoring intracellular H2O2 dynamics. We successfully tracked real-time transient and steady-state H2O2 levels in diverse biological systems, including human stem cell-derived neurons and cardiomyocytes, primary neurons and astrocytes, and mouse brain ex vivo and in vivo. These applications demonstrate oROS's capabilities to monitor H2O2 as a secondary response to pharmacologically induced oxidative stress and when adapting to varying metabolic stress. We showcased the increased oxidative stress in astrocytes via Aβ-putriscine-MAOB axis, highlighting the sensor's relevance in validating neurodegenerative disease models. Lastly, we demonstrated acute opioid-induced generation of H2O2 signal in vivo which highlights redox-based mechanisms of GPCR regulation. oROS is a versatile tool, offering a window into the dynamic landscape of H2O2 signaling. This advancement paves the way for a deeper understanding of redox physiology, with significant implications for understanding diseases associated with oxidative stress, such as cancer, neurodegenerative, and cardiovascular diseases.

Structure-guided engineering of a fast genetically encoded sensor for real-time H2O2 monitoring

Hydrogen Peroxide (H2O2) is a central oxidant in redox biology due to its pleiotropic role in physiology and pathology. However, real-time monitoring of H2O2 in living cells and tissues remains a challenge. We address this gap with the development of an optogenetic hydRogen perOxide Sensor (oROS), leveraging the bacterial peroxide binding domain OxyR. Previously engineered OxyR-based fluorescent peroxide sensors lack the necessary sensitivity or response speed for effective real-time monitoring. By structurally redesigning the fusion of Escherichia coli (E. coli) ecOxyR with a circularly permutated green fluorescent protein (cpGFP), we created a novel, green-fluorescent peroxide sensor oROS-G. oROS-G exhibits high sensitivity and fast on-and-off kinetics, ideal for monitoring intracellular H2O2 dynamics. We successfully tracked real-time transient and steady-state H2O2 levels in diverse biological systems, including human stem cell-derived neurons and cardiomyocytes, primary neurons and astrocytes, and mouse neurons and astrocytes in ex vivo brain slices. These applications demonstrate oROS's capabilities to monitor H2O2 as a secondary response to pharmacologically induced oxidative stress, G-protein coupled receptor (GPCR)-induced cell signaling, and when adapting to varying metabolic stress. We showcased the increased oxidative stress in astrocytes via Aβ-putriscine-MAOB axis, highlighting the sensor's relevance in validating neurodegenerative disease models. oROS is a versatile tool, offering a window into the dynamic landscape of H2O2 signaling. This advancement paves the way for a deeper understanding of redox physiology, with significant implications for diseases associated with oxidative stress, such as cancer, neurodegenerative disorders, and cardiovascular diseases.

The deformation of cancer cells through narrow micropores holds the potential to regulate genes that impact cancer malignancy

Surgery, radiation, hormonal therapy, chemotherapy, and immunotherapy are standard treatment strategies for metastatic breast cancer. However, the heterogeneous nature of the disease poses challenges and continues to make it life-threatening. It is crucial to elucidate further the underlying signaling pathways to improve treatment efficacy. Our study established two triple-negative breast cancer cell lines (TW-1 and TW-2) that were physically deformed using 3 μm pores to investigate the relationship between cancer cell deformation and metastasis within a heterogeneous population. The physical transformation of TW-1 and TW-2 cells significantly affected their growth and migration speed, as evidenced by wound healing assays for collective cell migration and microchannel assays for single-cell migration. We conducted bulk RNA sequencing to gain insights into the genes influenced by physical deformation. Additionally, we evaluated the effects of trametinib resistance on breast cancer cell metastasis by assessing cell viability and migration rates. Interestingly, TW-1 and TW-2 cells exhibited resistance to trametinib treatment. We observed a significant upregulation of GABRA-3, a protein commonly expressed in malignant breast cancer, and the critical transcription factor Myc in TW-1 and TW-2 cells compared to the control group (Ori). However, we did not observe a significant difference in Myc expression between TW-1 and TW-2 cells. In contrast, in the trametinib-resistant cell lines (TW-1-Tra and TW-2-Tra), we found increased expression of OCT4 and SOX2 rather than GABRA-3 or Myc. These findings highlight the differential expression patterns of these genes in our study, suggesting their potential role in cancer cell deformation and drug resistance. Our study presents a potential in vitro model for metastatic and drug-resistant breast cancer cells. By investigating the correlation between cancer cell deformation and metastasis, we contribute to understanding breast cancer heterogeneity and lay the groundwork for developing improved treatment strategies.

HDAC6 Inhibition Corrects Electrophysiological and Axonal Transport Deficits in a Human Stem Cell-Based Model of Charcot-Marie-Tooth Disease (Type 2D)

Charcot-Marie-Tooth disease type 2D (CMT2D), is a hereditary peripheral neuropathy caused by mutations in the gene encoding glycyl-tRNA synthetase (GARS1). Here, human induced pluripotent stem cell (hiPSC)-based models of CMT2D bearing mutations in GARS1 and their use for the identification of predictive biomarkers amenable to therapeutic efficacy screening is described. Cultures containing spinal cord motor neurons generated from this line exhibit network activity marked by significant deficiencies in spontaneous action potential firing and burst fire behavior. This result matches clinical data collected from a patient bearing a GARS1^P724H mutation and is coupled with significant decreases in acetylated α-tubulin levels and mitochondrial movement within axons. Treatment with histone deacetylase 6 inhibitors, tubastatin A and CKD504, improves mitochondrial movement and α-tubulin acetylation in these cells. Furthermore, CKD504 treatment enhances population-level electrophysiological activity, highlighting its potential as an effective treatment for CMT2D.

Human Induced Pluripotent Stem Cell-Derived TDP-43 Mutant Neurons Exhibit Consistent Functional Phenotypes Across Multiple Gene Edited Lines Despite Transcriptomic and Splicing Discrepancies

Gene editing technologies hold great potential to enhance our ability to model inheritable neurodegenerative diseases. Specifically, engineering multiple amyotrophic lateral sclerosis (ALS) mutations into isogenic cell populations facilitates determination of whether different causal mutations cause pathology via shared mechanisms, and provides the capacity to separate these mechanisms from genotype-specific effects. As gene-edited, cell-based models of human disease become more commonplace, there is an urgent need to verify that these models constitute consistent and accurate representations of native biology. Here, commercially sourced, induced pluripotent stem cell-derived motor neurons from Cellular Dynamics International, edited to express the ALS-relevant mutations TDP-43^M337V and TDP-43^Q331K were compared with in-house derived lines engineered to express the TDP-43^Q331K mutation within the WTC11 background. Our results highlight electrophysiological and mitochondrial deficits in these edited cells that correlate with patient-derived cells, suggesting a consistent cellular phenotype arising from TDP-43 mutation. However, significant differences in the transcriptomic profiles and splicing behavior of the edited cells underscores the need for careful comparison of multiple lines when attempting to use these cells as a means to better understand the onset and progression of ALS in humans.

Astrocyte-derived extracellular vesicles enhance the survival and electrophysiological function of human cortical neurons in vitro

Neurons derived from human induced pluripotent stem cells (hiPSCs) are powerful tools for modeling neural pathophysiology and preclinical efficacy/toxicity screening of novel therapeutic compounds. However, human neurons cultured in vitro typically do not fully recapitulate the physiology of the human nervous system, especially in terms of exhibiting morphological maturation, longevity, and electrochemical signaling ability comparable to that of adult human neurons. In this study, we investigated the potential for astrocyte-derived extracellular vesicles (EVs) to modulate survival and electrophysiological function of human neurons in vitro. Specifically, we demonstrate that EVs obtained from human astrocytes promote enhanced single cell electrophysiological function and anti-apoptotic behavior in a homogeneous population of human iPSC-derived cortical neurons. Furthermore, EV-proteomic analysis was performed to identify cargo proteins with the potential to promote the physiological enhancement observed. EV cargos were found to include neuroprotective proteins such as heat shock proteins, alpha-synuclein, and lipoprotein receptor-related protein 1 (LRP1), as well as apolipoprotein E (APOE), which negatively regulates neuronal apoptosis, and a peroxidasin homolog that supports neuronal oxidative stress management. Proteins that positively regulate neuronal excitability and synaptic development were also detected, such as potassium channel tetramerization domain containing 12 (KCTD12), glucose-6- phosphate dehydrogenase (G6PD), kinesin family member 5B (KIF5B), spectrin-alpha non-erythrocytic1 (SPTAN1). The remarkable improvements in electrophysiological function and evident inhibition of apoptotic signaling in cultured neurons exposed to these cargos may hold significance for improving preclinical in vitro screening modalities. In addition, our collected data highlight the potential for EV-based therapeutics as a potential class of future clinical treatment for tackling inveterate central and peripheral neuropathies.

Porphyromonas gingivalis Impairs Oral Epithelial Barrier through Targeting GRHL2

Oral mucosa provides the first line of defense against a diverse array of environmental and microbial irritants by forming the barrier of epithelial cells interconnected by multiprotein tight junctions (TJ), adherens junctions, desmosomes, and gap junction complexes. Grainyhead-like 2 (GRHL2), an epithelial-specific transcription factor, may play a role in the formation of the mucosal epithelial barrier, as it regulates the expression of the junction proteins. The current study investigated the role of GRHL2 in the Porphyromonas gingivalis (Pg)-induced impairment of epithelial barrier functions. Exposure of human oral keratinocytes (HOK-16B and OKF6 cells) to Pg or Pg-derived lipopolysaccharides (Pg LPSs) led to rapid loss of endogenous GRHL2 and the junction proteins (e.g., zonula occludens, E-cadherin, claudins, and occludin). GRHL2 directly regulated the expression levels of the junction proteins and the epithelial permeability for small molecules (e.g., dextrans and Pg bacteria). To explore the functional role of GRHL2 in oral mucosal barrier, we used a Grhl2 conditional knockout (KO) mouse model, which allows for epithelial tissue-specific Grhl2 KO in an inducible manner. Grhl2 KO impaired the expression of the junction proteins at the junctional epithelium and increased the alveolar bone loss in the ligature-induced periodontitis model. Fluorescence in situ hybridization revealed increased epithelial penetration of oral bacteria in Grhl2 KO mice compared with the wild-type mice. Also, blood loadings of oral bacteria (e.g., Bacteroides, Bacillus, Firmicutes, β-proteobacteria, and Spirochetes) were significantly elevated in Grhl2 KO mice compared to the wild-type littermates. These data indicate that Pg bacteria may enhance paracellular penetration through oral mucosa in part by targeting the expression of GRHL2 in the oral epithelial cells, which then impairs the epithelial barrier by inhibition of junction protein expression, resulting in increased alveolar tissue destruction and systemic bacteremia.

Cross-city comparison of indoor air temperatures in air-conditioned spaces

Field measurements were collected through physical measurements and observations in the cities of Seoul, Korea; Eugene and Portland, Oregon; and Yokohama, Japan, during the fall, winter, and summer seasons from 2005 to 2006. A total of 1733 data sets were collected (Seoul - 713; Oregon - 807; Yokohama - 213) in variety of multi-use buildings with the goal of examining operative temperatures and conditions encountered during everyday life. Of the four cities measured, winter and autumn indoor operative temperatures were highest in Seoul and lowest in Yokohama when normalized to outdoor conditions. In contrast, summer indoor operative temperatures were highest in Yokohama and lowest in Oregon. Clothing levels changed seasonally, and differences were observed between 'long-term occupants', 'residents', and 'transients.'

Synergistic tumoricidal effect between celecoxib and gabexate mesilate on the human breast cancer cells

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Background: Selective cyclooxygenase 2 (COX2) inhibitors, including celecoxib, has shown its antitumor effects against various cancers including breast cancer. Gabexate mesilate (GM) can be found to have anti-cancer activities against tumors such as colon cancer. We tried to determine whether synergism can exist between GM and celecoxib against human breast cancer cells. Methods: MCF7/Her18 (estrogen receptor positive) and MDA-MB-436 (estrogen receptor negative) human breast cancer cells were used. Celecoxib and GM were added into the culture media at a dose of 30 and 50 μM for estrogen receptor (ER) (+) cells and 50 and 75 μM for ER (-) cells. Cellular proliferation assays wer performed and trypan blue exclusion method was adopted to count the viable cells after culture. Cell cycle analysis and fluorescein-assorted cell sortings were done to check the cell cycle changes after treatment. Immunoblotting using Akt, phosphorylated Akt (p- Akt), β-catenin, COX2 and VEGF was done to evaluate changes in expression of these proteins. Results: Combination treatment group showed significantly enhanced tumoricidal effect than either mono-treatment group on cellular proliferation study. Combined treatment yielded more G1 phase population and G2-M phase cells. (p<0.05) The level of Akt, p-Akt, VEGF, COX2 expression were decreased more significantly than either mono-treatment group. (p<0.05) Conclusions: We think that there could be synergistic effect between GM and celecoxib on the human breast cancer cells. Either drug has been used for many cases without significant problem, and can be tried for further ex vivo studies to determine synergistic effects between them. Possible antiangiogenentic actions after the combination should be evaluated thoroughly in other cell lines to get more preclinical data.

No significant financial relationships to disclose.

Is the prophylactic use of colony stimulating factor and oral ciprofloxacin effective to prevent neutropenia in patients having docetaxel, doxorubicin, and cyclophosphamide for breast cancer as an adjuvant chemotherapy in Korea?

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Background: Recently, the combination chemotherapy including docetaxel (75 mg/m2), doxorubicin (adriamycin) (50 mg/m2), andcyclophosphamide (500 mg/m2) has been reported to be effective as an adjuvant treatment for the early breast cancer patients. Though a few studies have been published to show preventive effect of the routine use of G-CSF and oral antibiotics on the severe neutropenia. We prosepctively tried to compare the possible role of this prophylactic measure on the prevention of high-grade neutropenia in breast cancer patients having this regimen in Korea. Methods: We prospectively compared prophylactic user group (100 patients) with non-use group (100 patients). Stage II breast cancer patients were enrolled for this study. We used three-day prescription of G-CSF (150 ug/day) and oral ciprofloxacin (500 mg/day) five days after the completion of each cycle for the user-group. Results: The percentage of febrile neutropenia was strikingly decreased in the user group (p < .01). Number of patients showing grade II, III neutropenia didn’t show statistical difference between groups. Averge days required to recover from the neutropenia was 2.7days in two groups. The nadir of neutropenia was between 7–10 days after each cycle regardless of the prophylaxis. The duration of neutropenia seems to be dependent on the presence of the fever over 38’C after the chemotherapy. Once the fever developed, the neutropenia was becoming severer and more protracted. Conclusions: We think this combination chemotherapy effective to be used as an adjuvant treatment for the early breast cancer patients. But more care should be provided to prevent severe neutropenia after each cycle. Routine use of this prophylaxis failed to show significant differences in the rate of occurence of the severe neutropenia. But, we think that the prophylaxis seems to e effective to prevent febrile neutropenia. So, we suggest the routine prophylactic use of G-CSF and oral ciprofloxacin should be considered to be used in breast patients having docetaxel, adriamycin, and cyclophosphamide.

No significant financial relationships to disclose.

Trivalent inactivated influenza vaccine safety in children: Assessing the contribution of telephone encounters

We assessed the contribution of telephone medical care encounters to surveillance of adverse events (AE) following trivalent influenza vaccination in children age 6 months to 17 years. We used retrospective, self-controlled, case-series analysis to estimate adverse event incidence rate ratios for post-vaccination risk intervals relative to 15-28 days prior to vaccination. We confirmed possible vaccination reactions by medical record abstraction. Detection of 10 of 20 elevated incidence rate ratios required telephone data. We conclude that telephone encounters substantially contribute to the detection of possible influenza vaccination reactions, primarily local injection site and systemic reactions.

Incidence of herpes zoster, 1997-2002

We estimated age-specific herpes zoster (HZ) incidence rates in the Kaiser Permanente Northwest Health Plan (KPNW) during 1997-2002 and tested for secular trends and differences between residents of two states with different varicella vaccine coverage rates. The cumulative proportions of 2-year-olds vaccinated increased from 35% in 1997 to 85% in 2002 in Oregon, and from 25% in 1997 to 82% in 2002 in Washington. Age-specific HZ incidence rates in KPNW during 1997-2002 were compared with published rates in the Harvard Community Health Plan (HCHP) during 1990-1992. The overall HZ incidence rate in KPNW during 1997-2002 (369/100,000 person-years) was slightly higher than HCHP's 1990-1992 rate when adjusted for age differences. For children 6-14 years old, KPNW's rates (182 for females, 123 for males) were more than three times HCHP's rates (54 for females, 39 for males). This increase appears to be associated with increased exposure of children to oral corticosteroids. The percentage of KPNW children exposed to oral corticosteroids increased from 2.2% in 1991 to 3.6% in 2002. Oregon residents had slightly higher steroid exposure rates during 1997-2002 than Washington residents. There were significant increases in HZ incidence rates in Oregon and Washington during 1997-2002 among children aged 10-17 years, associated with increased exposure to oral steroids.

Intracanopy lighting of cowpea canopies in controlled environments

Traditional designs for plant-growth lighting in space life support systems irradiate tops of closed foliar canopies while canopy understories are light limited. "Intracanopy lighting," a technique whereby plants are allowed to grow up and around multiple layers of low-intensity lamps that irradiate interior portions of canopies, can potentially enhance productivity while reducing overall energy consumption. Intracanopy lighting of cowpea (Vigna unguiculata L. Walp) was optimized by varying stand densities and lining growth compartments with light-scattering or reflective films. Yield rates using intracanopy lighting were less than those obtained with traditional lighting strategies. However, yield efficiencies and energetic conversion efficiencies, parameters that put edible yield in terms of inedible biomass, energetic, spatial, and temporal penalties, indicate intracanopy lighting is more efficient in crop production. Single-leaf photosynthetic rates indicate all leaves participate in net carbon gain regardless of age and position within a canopy.

Pancreatic cancer cell-derived vascular endothelial growth factor is biologically active in vitro and enhances tumorigenicity in vivo

Vascular endothelial growth factor (VEGF) is a potent angiogenic stimulator that acts by binding to high-affinity transmembrane receptors. Although both VEGF and its receptors are overexpressed in human pancreatic ductal adenocarcinoma (PDAC), this malignancy is not generally considered to be highly vascular. It is not known, therefore, whether the abundance of VEGF in PDAC is biologically relevant. To address this issue, we measured the angiogenic effects of pancreatic cancer cell-derived VEGF in an in vitro endothelial cell proliferation assay and characterized the consequences of suppressing VEGF expression on pancreatic tumor growth in an athymic nude mouse model. We found that human pancreatic cancer cell lines secrete large quantities of biologically active VEGF into conditioned medium (CM). Stable transfection of an anti-sense VEGF(189) (AS-VEGF(189)) expression construct into PANC-1 pancreatic cancer cells resulted in decreased VEGF expression and secretion, a decreased capacity of the resultant CM to enhance endothelial cell proliferation and a significant attenuation of tumor cell proliferation in vitro. Furthermore, when injected into athymic nude mice, AS-VEGF(189)-expressing cells exhibited an 80% decrease in tumor growth compared with control cells. These results support the hypothesis that VEGF promotes pancreatic cancer growth in vivo and suggest that anti-VEGF therapy may be useful in the treatment of this disease.

Identification of a Drosophila brain-gut peptide related to the neuropeptide Y family

A neuropeptide F (NPF) was isolated from the fruit fly, Drosophila mellanogaster, based on a radioimmunoassay for a gut peptide from the corn earworm, Helicoverpa zea. A partial sequence was obtained from the fly peptide, and a genomic sequence coding for NPF was cloned after inverse polymerase chain reaction and shown to exist as a single genomic copy. The encoded, putative prepropeptide can be processed into an amidated NPF with 36 residues that is related to invertebrate NPF's and the neuropeptide Y family of vertebrates. In situ hybridization and immunocytochemistry showed that Drosophila NPF was expressed in the brain and midgut of fly larvae and adults.

Environmental modification of yield and nutrient composition of 'Waldmann's Green' leaf lettuce

Leaf number, dry weight, and nutrient composition of Lactuca sativa L. cv. Waldmann's Green leaves were compared following 9 days of treatment in a controlled environment room under various combinations of photosynthetic photon flux (PPF:350 vs 800 micromoles m-2 s-1), atmospheric CO2 level (ambient vs 1500 micromoles mol-1), and single-strength (1X:15 mM) vs double-strength (2X:30 mM) nitrogen (N) as NO3- alone or as NH4(+) + NO3- (1:5 molar ratio). CO2 enrichment greatly enhanced leaf number under all PPF and N conditions, but increased leaf dry weight only at high PPF. Conditions favoring high photosynthesis enhanced leaf starch content 3-fold, and protein content increased as much as 64% with 2X NH4(+)+NO3-. Free sugar content was 6 to 9% of leaf dry weight for all treatment combinations, while fat was 1.5 to 3.5%. Ash content varied from 15 to 20% of leaf dry weight. Modified controlled environments can be used to enhance the nutritional content as well as the yield of crops to be used for life support in space-deployed, self-sustaining human habitats. Leaf lettuce is a useful model crop for demonstrating the potential of nutritional value added by environmental manipulation.

Dynamic optimization of CELSS crop photosynthetic rate by computer-assisted feedback control

A procedure for dynamic optimization of net photosynthetic rate (Pn) for crop production in Controlled Ecological Life-Support Systems (CELSS) was developed using leaf lettuce as a model crop. Canopy Pn was measured in real time and fed back for environmental control. Setpoints of photosynthetic photon flux (PPF) and CO2 concentration for each hour of the crop-growth cycle were decided by computer to reach a targeted Pn each day. Decision making was based on empirical mathematical models combined with rule sets developed from recent experimental data. Comparisons showed that dynamic control resulted in better yield per unit energy input to the growth system than did static control. With comparable productivity parameters and potential for significant energy savings, dynamic control strategies will contribute greatly to the sustainability of space-deployed CELSS.

Dynamic control of photosynthetic photon flux for lettuce production in CELSS

A new dynamic control of photosynthetic photon flux (PPF) was tested using lettuce canopies growing in the Minitron II plant-growth/canopy gas-exchange system. Canopy photosynthetic rates (Pn) were measured in real time and fedback for further environment control. Pn can be manipulated by changing PPF, which is a good environmental parameter for dynamic control of crop production in a Controlled Ecological Life-Support Systems CELSS. Decision making that combines empirical mathematical models with rule sets developed from recent experimental data was tested. With comparable yield indices and potential for energy savings, dynamic control strategies will contribute greatly to the sustainability of space-deployed CELSS.

Combined radiotherapy and chemotherapy with bleomycin and methotrexate for advanced inoperable head and neck cancer: update of a Northern California Oncology Group randomized trial

Between 1978 and 1984, the Northern California Oncology Group (NCOG) conducted a randomized trial to study the efficacy of combined radiotherapy (RT) and chemotherapy (CT) for stage III or IV inoperable head and neck cancer. One hundred four patients were randomized to receive: (1) RT alone, or (2) RT plus CT. RT consisted of 7,000 cGy to the involved areas and 5,000 cGy to uninvolved neck at 180 cGy/fraction, five fractions/wk. CT consisted of bleomycin, 5 U intravenously (IV), twice weekly during RT, followed by bleomycin, 15 U IV, and methotrexate, 25 mg/m2 IV weekly for 16 weeks after completion of RT. Fifty-one patients in the RT alone group and 45 in the combined treatment group were evaluable. The local-regional complete response (CR) rate was 45% v 67% (P = .056); the 2-year local-regional control rate, including salvage surgery, was 26% v 64% (P = .001); and the incidence of distant metastasis was 24% v 38% (P greater than .25), for the RT alone and RT plus CT groups, respectively. The relapse-free survival curves were significantly different (P = .041), favoring the combined treatment. However, the survival curves were not significantly different (P = .16). Patient compliance to maintenance CT was poor. Bleomycin significantly increased the acute radiation mucositis, although the difference in late normal tissue toxicity was not statistically significant. Thus, bleomycin and concurrent RT produced a more favorable CR rate, local-regional control rate, and relapse-free survival, but the difference in survival was not statistically significant.

Influence of the original disease, race, and center on the outcome of kidney transplantation

The low graft survival rate in black recipients (36 +/- 2% at 1 year) as compared with the graft survival rate in white recipients (48 +/- 1%) might be secondary to a higher incidence of vascular lesions, inducing hypertensive disease, in blacks than in whites. The relative frequency of malignant hypertension in black recipients was six times that of white recipients, and recipients with malignant hypertension had a significant lower graft survival rate (43 +/- 2%) than recipients with glomerulonephritis (54 +/- 1%). In addition, patients with vascular lesions (diabetes, malignant hypertension, and glomerulonephritis) showed significantly lower graft survival rates in black than in white recipients, in contrast to patients with primary tubular or interstitial lesions (polycystic kidneys and pyelonephritis), who showed similar graft survival rates in blacks and whites. Only a small fraction of this racial effect could be traced back to the higher incidence of Lewis-negative phenotypes in black recipients and a similar beneficial effect of transfusions, on graft survival, was observed in both black and white recipients. The effects of graft survival of age (6%), race (9%), and transfusions (18%) were significant in good (A) and poor (B) centers. No overlap between A and B centers was observed for any of these three parameters when analyzed separately. However, when the cumulative effects of these three risk parameters were analyzed together a partial overlap appeared, i.e., higher graft survival rates were observed in low-risk recipients that received transplants in B centers than in high-risk recipients that received transplants in A centers. Consequently, the selection of the recipient may play a role in the overall results of different transplantation units, leading to their classification into A or B centers, but cannot explain all of the differences between A and B centers.

The Lewis system and kidney transplantation

A significant effect of Lewis antigens on cadaver kidney graft survival was found in 1,300 North American transplants. Lewis-negative recipients had a graft survival rate that was 8% lower than that of Lewis-positive recipients (P = 0.05). This effect of Lewis antigens was enhanced in patients at a high failure risk as determined by age, race, or transplant center. In patients older than 30 years, the effect of Lewis was 14% (P = 0.07), in non-Caucasians 12% (P = 0.07), in all grafts performed at centers with less than 50% overall 1-year graft survival 12% (P = 0.03), and in non-Caucasians that received transplants in centers with less than 50% overall graft survival it was 18% (p = 0.01). These data confirm previous results on the role of Lewis as a histocompatibility system in renal transplantation; furthermore, they demonstrate that the influence of Lewis is larger in patients at high risk.

Combined effects of HLA matching and age in renal transplantation

Recipient age and matching for the HLA-A and B antigens each influence the graft survival rate of cadaver kidney transplants by approximately 10%. These two factors are cumulative and have a combined effect of nearly 20%. Thus, other factors that have a relatively weak influence on graft success may have a combined effect that makes their clinical consideration highly relevant.