Direction of Temperature Control in the Thermal Biofeedback Treatment of Vascular Headache

In order to test for the specific therapeutic effects of thermal biofeedback (TBF) for hand warming on vascular headache (HA), 70 patients with chronic vascular HA were randomly assigned to TBF for hand warming, TBF for hand cooling, TBF for stabilization of hand temperature, or biofeedback to suppress alpha in the EEG. Patients in each condition initially had high levels of expectation of therapeutic benefit and found the treatment rationales highly credible. Participants in each condition received 12 treatment sessions on a twice-per-week basis. Based on daily HA diary data gathered for 4 weeks prior to treatment and 4 weeks after treatment, HA Index was significantly (p=.003) reduced as was HA medication consumption. There were no differential reducations in HA Index or Medication Index among the four conditions. Global self-reports of improvement gathered at the end of the post-treatment monitoring period also did not differ among the four conditions. We were unable to demonstrate a specific effect of TBF for hand warming on vascular HA activity.     

气候变化和林火干扰对大兴安岭林区地上生物量影响的动态模拟

预测森林地上生物量对气候变化和林火干扰的响应是陆地生态系统碳循环研究的重要内容,气温、降水等因素的改变和气候变暖导致林火干扰强度的变化将会影响森林生态系统的碳库动态.东北森林作为我国森林的重要组成部分,对气候变化和林火干扰的响应逐渐显现.本文运用LANDIS PRO模型,模拟气候变化对大兴安岭森林地上生物量的影响,并比较分析了气候变暖对森林地上生物量的直接影响与通过林火干扰强度改变所产生的影响.结果表明: 未来气候变暖和火干扰增强情景下,森林地上生物量增加;当前气候条件和火干扰下,研究区森林地上生物量为(97.14±5.78) t·hm^-2;在B1F2预案下,森林地上生物量均值为(97.93±5.83) t·hm^-2;在A2F3预案下,景观水平第100～150和150～200年模拟时期内的森林地上生物量均值较高,分别为(100.02±3.76)和(110.56±4.08) t·hm^-2.与当前火干扰相比,CF2预案(当前火干扰增加30%)在一定时期使景观水平地上生物量增加(0.56±1.45) t·hm^-2,CF3预案(当前火干扰增加230%)在整个模拟阶段使地上生物量减少(7.39±1.79) t·hm^-2.针叶、阔叶树种对气候变暖的响应存在差异,兴安落叶松和白桦生物量随气候变暖表现为降低趋势,而樟子松、云杉和山杨的地上生物量则随气候变暖表现出不同程度的增加;气候变暖对针阔树种的直接影响具有时滞性,针叶树种响应时间比阔叶树种迟25～50年.研究区森林对高CO₂排放情景下气候变暖和高强度火干扰的共同作用较为敏感,未来将明显改变研究区森林生态系统的树种组成和结构.     

On Interrelations between Temporal Parameters of the Calling Song of the Cricket Gryllus bimaculatus

Based on analysis of the temporal dynamics of parameters of the calling song in male crickets Gryllus bimaculatus, a conclusion has been made about the existence of a certain correlation between the number of pulses in chirps, on one hand, and chirp repetition periods and interchirp intervals, on the other hand. It is suggested that this correlation reflects a certain process running in the nervous system of a singing male with variable intensity that depends on both the external and the internal, including genetic, factors.     

Thermal feedback in Raynaud's phenomenon secondary to systemic lupus erythematosus: long-term remission of target symptoms

Thermal feedback shows promise when applied to Raynaud's phenomenon secondary to systematic lupus erythematosus (SLE). A female subject was followed over an 8-year period that included initial training, 1-year follow-up, and 8-year follow-up. Peripheral circulation was initially very poor, as evidenced by low basal fingertip temperatures and trophic lesions at the fingernails. An intensive 5-week training regimen in thermal self-regulation yielded evidence of hand warming, followed by an increase in basal finger temperature. Reported vasospasms were markedly reduced and the lesions healed in the ensuing weeks. As of the 1-year follow-up, the skill was intact. Symptoms remained in substantial remission throughout the 8-year period during which the subject practiced somatic relaxation and hand warming without electronic feedback. Objective temperature measurement at the 8-year juncture yielded results similar to the initial acquisition, gradual manifestation of control over the first 4 days. The subject also reported diminution of vascular headache, another symptom of SLE. While much of the biofeedback literature is focused on stress-related disease, research of this kind affirms the value of self-regulatory technique in illnesses whose causes are primarily physical.     

Thermal feedback in Raynaud's phenomenon secondary to systemic lupus erythematosus: Long-term remission of target symptoms

Thermal feedback shows promise when applied to Raynaud's phenomenon secondary to systematic lupus erythematosus (SLE). A female subject was followed over an 8-year period that included initial training, I-year follow-up, and 8-year follow-up. Peripheral circulation was initially very poor, as evidenced by low basal fingertip temperatures and trophic lesions at the fingernails. An intensive 5-week training regimen in thermal self-regulation yielded evidence of hand warming, followed by an increase in basal finger temperature. Reported vasospasms were markedly reduced and the lesions healed in the ensuing weeks. As of the 1-year follow-up, the skill was intact. Symptoms remained in substantial remission throughout the 8-year period during which the subject practiced somatic relaxation and hand warming without electronic feedback. Objective temperature measurement at the 8-year juncture yielded results similar to the initial acquisition, gradual manifestation of control over the first 4 days. The subject also reported diminution of vascular headache, another symptom of SLE. While much of the biofeedback literature is focused on stress-related disease, research of this kind affirms the value of self-regulatory technique in illnesses whose causes are primarily physical.     

Diurnal variation of tension-type headache intensity and exacerbation: An investigation using computerized ecological momentary assessment

ABSTRACT: BackgroundsTension-type headache is a common psychosomatic disease. However, diurnal variation of headache is yet to be clarified, perhaps due to the lack of an appropriate method to investigate it. Like other painful diseases, it would be helpful to know if there is diurnal variation in tension-type headaches, both for managing headaches and understanding their pathophysiology. The aim of this study was to determine if there is diurnal variation in the intensity and exacerbation of tension-type headache. METHODS: Patients (N = 31) with tension-type headache recorded for one week their momentary headache intensity several times a day and their acute headache exacerbations using a watch-type computer as an electronic diary (computerized ecological momentary assessment). Multilevel modeling was used to test the effects of time of day on momentary headache intensity and on the occurrence of acute exacerbations. RESULTS: A significant diurnal variation in momentary headache intensity was shown (P = 0.0005), with the weakest headaches in the morning and a peak in the late afternoon. A between-individual difference in the diurnal pattern was suggested. On-demand medication use was associated with a different diurnal pattern (P = 0.025), suggesting that headache intensity decreases earlier in the evening in subjects who used on-demand medication, while headache subtype, prophylactic medication use, and sex were not associated with the difference. The occurrence of acute headache exacerbation also showed a significant diurnal variation, with a peak after noon (P = 0.0015). CONCLUSIONS: Tension-type headache was shown to have a significant diurnal variation. The relation to pathophysiology and psychosocial aspects needs to be further explored.     

Protein SH-group concentration and RNA synthesis during the process of induction of proliferation in the stationary phase of cell culture growth]

The dynamics of intracellular protein SH-group (PSH) content was studied cytochemically in the course of stimulation of cell proliferation in stationary cultures of an established Chinese hamster cell line and of human diploid embryo fibroblasts. The results were compared with the pattern of RNA synthesis during the prereplicative period. In Chinese hamster cells immediately after medium changing in stationary cultures there is an augmentation of PSH content in parallel withe the increase in RNA synthesis rate. Later on, the rate of RNA synthesis and PSH content are seen decreasing followed by a new increase in the rate of RNA synthesis correlated with the second rise in PSH content. In stationary cultures of human diploid fibroblasts, there is also an increase in the rate of RNA synthesis and in the content of SH after medium changing, but the second wave of RNA synthesis and the second rise in PSH content are not pronounced. The variation in PSH content reflects the shift in the cell metabolism during the prereplicative period and is not attributed to changes in cell protein content.     

Same sexual system but variable sociobiology: evolution of protandric simultaneous hermaphroditism in Lysmata shrimps

The sexual system of the decapod (caridean) shrimp Lysmata isprotandric simultaneous hermaphroditism (PSH). Individuals firstmature as males (male phase = MP) and then when older (larger)change to the external phenotype of female carideans (femalephase = FP). However, unlike purely protandric carideans, LysmataFPs retain reduced male gonadal tissues and ducts, and are ableto mate nonreciprocally as males as well as to reproduce asfemales. Thus, FPs of Lysmata species are functional simultaneoushermaphrodites although most reproductive effort is devotedto embryo production and incubation. The question explored hereis, given the propensity of carideans to protandry, the apparentlow cost, and high reproductive advantage of PSH, why has notPSH evolved more frequently? The mating systems and sexual selectionof caridean shrimps, the original sex of protandric individuals,the cost of maleness, and sex allocation theory are discussedin relation to protandry and PSH. None of these factors adequatelyexplains the evolution of PSH of Lysmata species. Lysmata hasat least 2 species groups with very different sociobiologies;these groups do not appear to share current selective pressuresthat would explain PSH in both. A historical contingency hypothesis,testable in part with a phylogenetic analysis, may explain theevolution of PSH in Lysmata.     

Effect of anoxia on diapause termination in eggs of the false melon beetle, Atrachya menetriesi

The effect of anoxia on diapause development in the leaf beetle Atrachya menetriesi was investigated to elucidate the role of oxygen in regulation of egg diapause. While anoxia alone had no effect on diapause termination, it decreased diapause intensity before chilling. Such an effect reached a maximum level when anoxia lasted for about 10 days. Anoxia applied during the pre-diapause stage also reduced diapause intensity. On the other hand, anoxia terminated diapause when the diapause intensity had been lowered by sufficient duration of chilling (50 days at 7.5 degrees C). The effect of anoxia was temperature dependent; the larger effect was elicited when anoxia was combined with a higher temperature. A 50-day chilling caused more than 20% of eggs to terminate diapause upon transfer to warm conditions. However, when this chilling period was interrupted on the 20th day by a 5-day exposure to a high temperature of 20, 25 or 30 degrees C, the effect of the former chilling was cancelled partially or completely, suggesting that warming reversed diapause development. This reversing effect of a high temperature, however, was not manifested when the warming was combined with anoxia. The results suggest that anoxia inhibits diapause reversal and facilitates a certain process of diapause development. The sequence of exposure to anoxia and chilling is not important.     

The effects of ionizing radiation on DNA: the role of thiols as radioprotectors

Electron loss from N-(2-mercaptopropionyl) glycine (PSH) gave an EPR detectable radical anion, PS-.SP(-). When the PSH derivative was frozen in aqueous DNA solutions to 77 K and exposed to ionizing radiation, normal damage to the DNA was detected by EPR spectroscopy. However, on annealing above 77 K, central EPR features for the DNA base radical cations and anions gave central features assigned to PS-.SP(-) sigma*-radical anions, together with outer features for 5-6-dihydro-5-thymyl radicals, TH.. It is proposed that on freezing, the PSH molecules are constrained into a glassy region around the DNA, and that, on annealing, electron donation gives PS. radicals, with loss of quanine radical-cations, G(.+). The PS. radicals were not detectable, but on reaction with another PSH molecule, gave good EPR spectra for PS-.SP(-) radical-anions. These results indicate that PSH had little effect on the yield of the other base radicals C(.-)/T(.-). Also, growth of TH. radicals, formed from protonated thymine radical-anions, T(.-), were detected. We conclude that the primary effect of PSH is to capture the G(.+) centers, and thus could either prevent or repair radiation damage to DNA.     

Pinostilbene hydrate suppresses hepatic stellate cell activation via inhibition of miR-17–5p-mediated Wnt/β-catenin pathway

BackgroundIn the development of liver fibrosis, activated hepatic stellate cells (HSCs) contribute to the synthesis and deposition of extracellular matrix (ECM) proteins. HSC activation is considered as a central driver of liver fibrosis. Recently, microRNAs (miRNAs) have been reported to act as key regulators in HSC activation.PurposePinostilbene hydrate (PSH), a methylated derivative of resveratrol, has demonstrated anti-inflammatory, antioxidant and anti-tumour activities. However, the effects of PSH on HSC activation remain unclear.MethodsThe effects of PSH on HSC activation were examined. Moreover, the roles of WNT inhibitory factor 1 (WIF1) and miR-17–5p in the effects of PSH on HSC activation were examined.ResultsPSH induced a significant reduction in HSC proliferation. PSH also effectively inhibited HSC activation, with reduced α-SMA and collagen expression. Notably, it was found that Wnt/β-catenin signalling was involved in the effects of PSH on HSC activation. PSH resulted in Wnt/β-catenin signalling inactivation, with a reduction in TCF activity as well as β-catenin nuclear translocation. Further studies showed that PSH inhibited Wnt/β-catenin signalling via regulation of WIF1 and miR-17–5p. Reduced HSC activation caused by PSH could be restored by loss of WIF1 or miR-17–5p mimics. Luciferase reporter assays further confirmed that WIF1 was a target of miR-17–5p.ConclusionPSH has a significant protective effect against HSC activation. In addition, we demonstrate that PSH enhances WIF1 expression and inhibits Wnt/β-catenin signalling via miR-17–5p, contributing to the suppression of HSC activation.     

Pulmonary sclerosing hemangioma: report of two cases

ABSTRACT: Pulmonary sclerosing hemangioma (PSH) is a rare benign tumor of the lungs. These tumors are composed of cuboidal surface cells and polygonal stromal cells and show four histological manifestations: hemorrhagic, papillary, solid, and sclerotic. PSH predominantly affects asymptomatic middle-aged women. The tumor often occurs at the intralobar site, and less commonly in the bronchus and mediastinum. PSH is easy to be misdiagnosed preoperatively. In this study, we present in detail the treatment procedures followed for two atypical cases of PSH. Case 1 was a 62-year-old woman bearing a tumor for 15 years. The tumor lesion was found to be located in the oblique fissure of the left lung. PSH was confirmed by surgical resection and postoperative pathological diagnosis. There was no sign of recurrence and metastasis 1.5 years after surgery. Case 2 was a 54-year-old woman diagnosed with bilateral multiple nodules by physical examination. This patient was diagnosed with definite PSH through computed tomography-guided percutaneous lung biopsy. Surgical resection was not performed. The patient also showed no sign of enlarged tumor and metastasis after 2 years of follow-up. Although PSH can be cured by surgical resection, the findings in our cases indicate that surgical resection need not be considered the preferred course of treatment. If PSH is diagnosed before surgery, the patients may survive while bearing the tumor.     

Profile of mood states and stress-related biochemical indices in long-term yoga practitioners

Background

Both insufficient sleep and oversleeping have been reported as precipitating and aggravating factors of tension-type headache (TTH). However, previous studies relied on recalled self-reports, and the relationship has not been confirmed prospectively and objectively in a daily life situation. Recently, ecological momentary assessment (EMA) using electronic diaries, i.e., computerized EMA, is used to record subjective symptoms with the advantages of avoiding recall bias and faked compliance in daily settings. In addition, actigraphy has become an established method to assess sleep outside laboratories. Therefore, the aim of this study was to investigate the within-individual effect of sleep on the following momentary headache intensity in TTH patients during their daily lives utilizing EMA and actigraphy.

Methods

Twenty-seven patients with TTH wore watch-type computers as electronic diaries for seven consecutive days and recorded their momentary headache intensity using a visual analog scale of 0-100 approximately every six hours, on waking up, when going to bed, and at the time of headache exacerbations. They also recorded their self-report of sleep quality, hours of sleep and number of awakenings with the computers when they woke up. Physical activity was continuously recorded by an actigraph inside the watch-type computers. Activity data were analyzed by Cole's algorithm to obtain total sleep time, sleep efficiency, sleep latency, wake time after sleep onset and number of awakenings for each night. Multilevel modeling was used to test the effect of each subjective and objective sleep-related variable on momentary headache intensity on the following day.

Results

Objectively measured total sleep time was significantly positively associated with momentary headache intensity on the following day, while self-reported sleep quality was significantly negatively associated with momentary headache intensity on the following day.

Conclusions

Using computerized EMA and actigraphy, longer sleep and worse sleep quality were shown to be related to more intense headache intensity on within-individual basis and they may be precipitating or aggravating factors of TTH.     

Thiolation and nitrosation of cysteines in biological fluids and cells

Summary. Thiols (RSH) are potent nucleophilic agents, the rates of which depend on the pKa of the sulfhydryl. Unlike compounds having other nucleophile moieties (–OH or –NH₂), RSH are involved in reactions, such as conjugations, redox and exchange reactions. Although protein SH groups (PSH) react like non-protein thiols (NPSH), the biochemistry of proteins is much more complex for reasons such as steric hindrance, charge distribution and accessibility of PSH to the solvent (protein conformation). The reaction rates and types of end-products of PSH vary a lot from protein to protein. The biological problem is even more complex because in all compartments and tissues, there may be specific competition between thiols (namely between GSH and PSH), regulated by the properties of antioxidant enzymes. Moreover, PSH are divided biologically into essential and non-essential and their respective influence in the various biological systems is unknown. It follows that during phenomena eliciting a prompt thiol response (oxidative stress), the antioxidant PSH response and reaction mechanisms vary considerably from case to case. For example, in spite of a relatively low pKa that should guarantee good antioxidant capacity, PSH of albumin has much less propensity to form adducts with conjugating agents than NPSH; moreover, the structural characteristics of the protein prevent albumin from forming protein disulfides when exposed to oxidants (whereas protein-thiol mixed disulfides are formed in relative abundance). On the other hand, proteins with a relatively high reactivity, such rat hemoglobin, have much greater antioxidant capacity than GSH, but although human hemoglobin has a pKa similar to GSH, for structural reasons it has less antioxidant capacity than GSH.When essential PSH are involved in S-thiolation and S-nitrosation reactions, a similar change in biological activity is observed. S-thiolated proteins are a recurrent phenomenon in oxidative stress elicited by reactive oxygen species (ROS). This event may be mediated by disulfides, that exchange with PSH, or by the protein intermediate sulfenic acid that reacts with thiols to form protein-mixed disulfides. During nitrosative stress elicited by reactive nitrogen species (RNS), depending on the oxygen concentration of the system, nitrosation reactions of thiols may also be accompanied by protein S-thiolation. In this review we discuss a number of cell processes and biochemical modifications of enzymes that indicate that S-thiolation and S-nitrosation may occur simultaneously in the same protein in the presence of appropriate interactions between ROS and RNS.     

Flow cytometric analysis of protein thiol groups in relation to the cell cycle and the intracellular content of glutathione in rat hepatocytes

The relationship between protein thiols (PSH) and cell proliferation was examined in ethanol-fixed rat hepatocytes. A new protocol was developed for simultaneous measurement of protein thiol vs. DNA content by flow cytometry. The fluorescent dye o-phthalaldehyde (OPT) was used for flow cytometric measurements of protein thiol groups. The influence of nonprotein thiols was examined by monitoring the cell cycle of cells in which the glutathione content (GSH) was modified by treatment with buthionine sulphoximine (BSO). Three rat liver cell lines (IAR 20, IAR 6.1, IAR 6.1RT7) were used: these cell lines possess different growth characteristics and degrees of tumorigenicity, which made it possible to analyse changes in PSH during normal and deranged cell proliferation. The effects on the cell cycle of the changes in PSH due to the depletion of GSH were measured by 5-bromo-2'-deoxyuridine (BrdUrd) incorporation and flow cytometry. The data obtained can be summarised as follows: a) OPT fluorescence increases with increasing DNA content in all rat liver cell lines examined; b) the greatest variation in PSH content occurs in G1. There is a smaller variation in G2 + M, and PSH levels are relatively invariant throughout S-phase; c) a higher content of PSH is found in the tumorigenic cell lines; d) the amount and distribution of PSH is not affected by BSO treatment; e) kinetic studies indicate that BSO treatment has no effect on the ability of the IAR rat liver cell lines to progress through the cycle.     

Weekly headache periodicity and the effect of weather changes on headache

A weekly periodicity in the occurrence of headache was found in 53 patients with migraine and in 20 with tension headache during an observation period of four weeks. In the migraine group the frequency was highest on Thursday and on Saturday and lowest on Sunday–Monday, and in patients with tension headache it was lowest on Sunday–Tuesday and highest on Friday. During the observation period several climatic factors were recorded. After correction for the weekly periodicity a highly significant correlation was found in the migraine group between headache frequency, on the one hand, and atmospheric pressure and outdoor temperature recorded 1–3 days later, on the other.     

长期增温对树线交错带岷江冷杉幼苗异龄叶大小与出叶强度关系的影响

全球气候变暖强烈影响树线交错带植物的生活史策略,异龄叶大小-出叶强度权衡关系是常绿植物生活史策略的重要内容。以川西树线交错带的岷江冷杉（Abies faxoniana）幼苗为例,研究气候变暖对异龄叶大小与出叶强度关系的影响。通过开顶箱（Open-top chamber, OTC）对川西王朗自然保护区树线交错带的岷江冷杉进行模拟增温,采用标准化主轴估计（Standardized major axis estimation, SMA）方法研究了叶大小（单叶质量、单叶面积）与出叶强度（基于茎生物量、茎体积）间异速生长关系对长期增温的响应及其年际变化。结果表明：使用不同参数表征叶大小与出叶强度得到的结果存在差异;多年生小枝上存在单叶质量-出叶强度的负等速权衡关系,共同主轴随小枝年龄增加而向下漂移;长期增温并不影响单叶质量与出叶强度的异速生长关系,不同年龄小枝的异速生长常数对增温具有差异性响应。增温处理中当年生小枝在相同单叶质量下的出叶强度更低,以换取叶片总数的增加,使小枝具有更大的可塑性而适应增温。本研究提供了岷江冷杉幼苗协调异龄叶大小与出叶强度从而适应长期增温的证据,为评估树木生长随气候变化而加速提供了理论参考。     

The role of mitochondrial glutathione and cellular protein sulfhydryls in formaldehyde toxicity in glutathione-depleted rat hepatocytes

Depletion of cellular GSH by diethyl maleate (DEM) potentiates CH2O toxicity in isolated rat hepatocytes and it was postulated that this increase in toxicity is due to the further decrease in GSH caused by CH2O in DEM-pretreated hepatocytes (1). The present investigation was conducted to investigate further the effects of CH2O, DEM, and acrolein (a compound which is structurally related to CH2O and DEM) on subcellular GSH pools and on protein sulfhydryl groups (PSH). CH2O caused a decrease in cytosolic GSH but had no effect on mitochondrial GSH either in previously untreated hepatocytes or in DEM-pretreated hepatocytes in which GSH was approximately 25% of control. DEM decreased both cytosolic and mitochondrial GSH but it did not produce toxicity. Neither CH2O (up to 7.5 mM) nor DEM (20 mM) decreased PSH. However, in cells pretreated with 1 mM DEM, CH2O (7.5 mM) decreased PSH and this effect preceded cell death. Acrolein decreased both cytosolic and mitochondrial GSH and it also decreased PSH significantly prior to causing cell death. CH2O and acrolein stimulated phosphorylase alpha activity, indicative of an increase in cytosolic free Ca2+, by a PSH-independent and PSH-dependent mechanism, respectively. These results suggest that the further depletion of cellular GSH by CH2O in DEM-pretreated cells is not due to the depletion of mitochondrial GSH. CH2O toxicity in DEM-pretreated cells is, however, correlated with depletion of PSH. The critical sulfhydryl protein(s) responsible for cell death remain to be more clearly defined.     

Relative contribution of two mechanisms to post-stimulus hyperpolarization in leech retzius cells

• 1.1. In Retzius cells of the horse leech, Haemopis sanguisuga, intensive firing is followed by prolonged post-stimulus hyperpolarization (PSH) mediated by an increase in K-conductance and activation of the electrogenic sodium pump.
• 2.2. The recovery of membrane potential during PSH can be described by a biexponential model from which the relative contribution of the early and the late component to the peak amplitude of PSH may be calculated.
• 3.3. The time course of the calculated early component coincides with the time course of changes that occur in input membrane resistance during PSH.
• 4.4. The relative contribution of the late component increases linearly with an increase in stimulus duration. The rate constants of the two phases did not change with changes in stimulus duration.
• 5.5. It was concluded that the proposed model is useful for the estimation of the relative contribution and kinetics of two PSH mediating mechanisms (K-conductance increase and activation of an electrogenic sodium pump) in different experimental conditions.

     

Soil respiration response to climate change in Pacific Northwest prairies is mediated by a regional Mediterranean climate gradient

Soil respiration is expected to increase with rising global temperatures but the degree of response may depend on soil moisture and other local factors. Experimental climate change studies from single sites cannot discern whether an observed response is site‐dependent or generalizable. To deconvolve site‐specific vs. regional climatic controls, we examined soil respiration for 18 months along a 520 km climate gradient in three Pacific Northwest, USA prairies that represents increasingly severe Mediterranean conditions from north to south. At each site we implemented a fully factorial combination of 2.5–3 °C warming and 20% added precipitation intensity. The response of soil respiration to warming was driven primarily by the latitudinal climate gradient and not site‐specific factors. Warming increased respiration at all sites during months when soil moisture was not limiting. However, these gains were offset by reductions in respiration during seasonal transitions and summer drought due to lengthened periods of soil moisture limitation. The degree of this offset varied along the north–south climate gradient such that in 2011 warming increased cumulative annual soil respiration 28.6% in the northern site, 13.5% in the central site, and not at all in the southern site. Precipitation also stimulated soil respiration more frequently in the south, consistent with an increased duration of moisture limitation. The best predictors of soil respiration in nonlinear models were the Normalized Difference Vegetation Index (NDVI), antecedent soil moisture, and temperature but these models provided biased results at high and low soil respiration. NDVI was an effective integrator of climate and site differences in plant productivity in terms of their combined effects on soil respiration. Our results suggest that soil moisture limitation can offset the effect of warming on soil respiration, and that greater growing‐season moisture limitation would constrain cumulative annual responses to warming.