Why infest the loved ones – inherent human behaviour indicates former mutualism with head lice

Parasitology ◽  
2012 ◽  
Vol 139 (6) ◽  
pp. 696-700 ◽  
Author(s):  
LAJOS RÓZSA ◽  
PÉTER APARI
Keyword(s):  
Immune Response ◽  
The Body ◽  
Head Lice ◽  
Body Louse ◽  
Trench Fever ◽  
Epidemic Typhus ◽  
New Hosts ◽  
Cross Immunity ◽  
Lice Infestations ◽  
Body Lice

SUMMARYHead lice transmit to new hosts when people lean their heads together. Humans frequently touch their heads to express friendship or love, while this behaviour is absent in apes. We hypothesize that this behaviour was adaptive because it enabled people to acquire head lice infestations as early as possible to provoke an immune response effective against both head lice and body lice throughout the subsequent periods of their life. This cross-immunity could provide some defence against the body-louse-borne lethal diseases like epidemic typhus, trench fever, relapsing fever and the classical plague. Thus the human ‘touching heads’ behaviour probably acts as an inherent and unconscious ‘vaccination’ against body lice to reduce the threat exposed by the pathogens they may transmit. Recently, the eradication of body-louse-borne diseases rendered the transmission of head lice a maladaptive, though still widespread, behaviour in developed societies.

The ‘head’ and ‘body’ races of Pediculus humanus L.

Parasitology ◽  
1948 ◽  
Vol 39 (1-2) ◽  
pp. 1-16 ◽  
Author(s):  
J. R. Busvine
Keyword(s):  
Head Louse ◽  
Antennal Segment ◽  
Egg Laying ◽  
The Body ◽  
Head Width ◽  
Abdominal Muscles ◽  
Head Lice ◽  
Body Louse ◽  
Significant Difference ◽  
Body Lice

1. Measurements were made of the head length, head width, total body length, antenna length, length and breadth of 3rd antennal segment of head and body lice from natural infestations. In all measurements (except the last) the means were significantly different for. the two forms, but in all cases there was considerable overlap.2. Head lice reared continuously on the body for forty-three generations (over 2 years) did not change systematically in size. Body lice reared under similar conditions were likewise constant.3. There was a highly significant difference between mean measurements of all the samples of head lice reared for up to 2 years on the body when compared with body lice reared for a similar period in the same way. The means for lice worn 24 hr. per day were less than those worn 12 hr. per day in both strains. An experiment showed that this is probably due to a difference in average temperature.4. The mean live weights of head and body strains were even more distinct than linear dimensions on the several occasions when these were recorded.5. Measurements of the dimensions of the opercula of the eggs of the two races and the numbers of air cells in them were distributed in the same way as the body measurements: that is, distinct means but overlapping individuals.6. Ventral abdominal muscles in wild head lice are typically confined to segment 5. (The forty specimens examined adhered to this rule.) In wild body lice, muscles are usually also present in segment 4 as well.7. Hybrids (female body x male head louse) were fertile for several generations. In size, the F1 generation was intermediate, but the F2 and F3 generations became identical with the body louse strain.8. Eggs of the body louse strain hatched at the same time as those of the head strain, but the body strain reached a significantly higher percentage hatch.9. The times of moulting during development were studied in both races in relation to differing opportunities to feed (24, 12, 6 and 3 hr. per day). The two strains showed very similar reactions in regard to speed of development, but throughout there was a higher pre-imaginal mortality in the head strain.10. Head lice were shown to be considerably more susceptible to starvation than body lice.11. If adults of the two strains are mixed, there is no tendency towards homogeneous mating. Of the mixed matings, those between body louse males and head louse females are much more common than the reverse.12. Female head lice show a slight difference in their egg-laying preferences when offered a choice of hair, voile and tape.My thanks are due to Prof. P. A. Buxton, F.R.S., for a number of helpful suggestions based on his extensive knowledge of louse biology and to Dr J. O. Irwin for critical comments on the statistical issues.

scholarly journals The Role of Th17 Response in COVID-19

Cells ◽  
2021 ◽  
Vol 10 (6) ◽  
pp. 1550
Author(s):  
Diana Martonik ◽  
Anna Parfieniuk-Kowerda ◽  
Magdalena Rogalska ◽  
Robert Flisiak
Keyword(s):  
Immune Response ◽  
Treg Cells ◽  
The Body ◽  
System Response ◽  
Th17 Response ◽  
Monocyte Chemoattractant Protein 1 ◽  
Acute Infectious Disease ◽  
Cytokine Cascade ◽  
Necrosis Factor

COVID-19 is an acute infectious disease of the respiratory system caused by infection with the SARS-CoV-2 virus (Severe Acute Respiratory Syndrome Coronavirus 2). Transmission of SARS-CoV-2 infections occurs through droplets and contaminated objects. A rapid and well-coordinated immune system response is the first line of defense in a viral infection. However, a disturbed and over-activated immune response may be counterproductive, causing damage to the body. Severely ill patients hospitalised with COVID-19 exhibit increased levels of many cytokines, including Interleukin (IL)-1β, IL-2, IL-6, IL-7, IL-8, IL-10, IL-17, granulocyte colony stimulating factor (G-CSF), monocyte chemoattractant protein 1 (MCP-1) and tumor necrosis factor (TNF). Increasing evidence suggests that Th17 cells play an important role in the pathogenesis of COVID-19, not only by activating cytokine cascade but also by inducing Th2 responses, inhibiting Th1 differentiation and suppressing Treg cells. This review focuses on a Th17 pathway in the course of the immune response in COVID-19, and explores plausible targets for therapeutic intervention.

scholarly journals Deterministic approaches for head lice infestations and treatments

2020 ◽  
Vol 5 ◽  
pp. 386-404
Author(s):  
Noemi Castelletti ◽  
Maria Vittoria Barbarossa
Keyword(s):  
Head Lice ◽  
Lice Infestations

Effects of Moringa Oleifera Leaf Polysaccharide on Growth Performance and Immune Response of Broiler Chickens

2021 ◽  
Author(s):  
Hosameldeen Mohamed Husien ◽  
JunJie Huang ◽  
WeiLong Peng ◽  
ShuMei Zheng ◽  
JinGui Li
Keyword(s):  
Immune Response ◽  
Growth Performance ◽  
Broiler Chickens ◽  
Moringa Oleifera ◽  
The Body ◽  
Feed Consumption ◽  
Feed Additive ◽  
Control Group ◽  
High Dose ◽  
Tnf Α

Abstract Moringa oleifera (MO) is a widely used as the nutritious and non-traditional feed supplementation containing kinds of bioactive substances. However, the enhancement effect of Moringa oleifera leaf Polysaccharide (MOLP) as a feed additive in broilers growth performance and immunity remains unclear. In this study, MOLP was obtained by water extraction and alcohol precipitation method, then purified with Trichloroacetic acid (TCA) assay. Chickens were randomly divided into 4 groups, to receive different doses of MOLP (0, 0.1, 0.2, 0.4g/kg) in feed for 3 weeks. The body weight gain (BWG) and feed consumption were recorded for feed conversion ratio (FCR) and average daily feed intake (ADFI) calculation. Broiler chickens were sacrificed and sampled on day 14, 21, 28 (D 14, D 21, and D 28) respectively. Serological indicators, including total protein (TP), albumin (ALB), globulin (GLO), and creatinine (CREA) were detected. ELISA kits were applied for detecting the levels of immunoglobulin A (IgA), immunoglobulin G (IgG), interleukin-2 (IL-2), and tumor necrosis factor (TNF-α). From D 21 to D 28, the results showed that middle dose of MOLP significantly increased BWG and ADFI as well as liver and bursa indexes when compared with the control group. In addition, TP and GLO were also increased (P<0.05). All MOLP treatments enhanced the serum concentrations of IgG and IL-2 (P<0.01). Furthermore, results of quantitative RT-PCR showed that high dose of MOLP treatment significantly increased (P<0.001) the mRNA expression levels of IL-2 and TNF-α of chickens relative to the control group. In conclusion, the results showed that MOLP supplementation contributed to improve growth performance and immune response in broiler chickens, and MOLP could be considered as a promising feed additive.

Lice

1995 ◽  
Vol 16 (9) ◽  
pp. 336-337
Author(s):  
Howard C. Sonnenblick
Keyword(s):  
Direct Contact ◽  
Common Type ◽  
The Body ◽  
School Age Children ◽  
School Age ◽  
Sexually Active ◽  
Head Lice ◽  
Pediculosis Capitis ◽  
Small Children ◽  
Pediculosis Pubis

Three forms of pediculosis affect the human host, each with a predilection for certain parts of the body. Pediculosis capitis. or head lice, is the most common type and is seen primarily in preschool and school-age children, especially girls. Transmission occurs by coming into direct contact with lice or by sharing infested brushes, combs, and hats. Adult lice and their eggs (nits) are found principally in the occipital region and behind the ears. Symptoms include severe itching, often resulting in excoriation and secondary bacterial infection. Pediculosis pubis is seen most commonly in sexually active adolescents and young adults, although occasionally it may be found on the eyelashes of small children who come in contact with infected individuals.

The influence of nutrition on egg-production and longevity in unmated female body-lice (Pediculus humanus corporis: Anoplura)

Parasitology ◽  
1941 ◽  
Vol 33 (1) ◽  
pp. 40-46 ◽  
Author(s):  
A. J. Haddow
Keyword(s):  
Female Body ◽  
Egg Production ◽  
Egg Laying ◽  
The Body ◽  
Unmated Female ◽  
Pediculus Humanus ◽  
The Third ◽  
Significant Difference ◽  
The Mean ◽  
Body Lice

1. Isolated unmated female body-lice were worn in pillboxes between the skin and the clothes. They were kept constantly on the body but, by a simple device, groups of ten were permitted feeding periods of different length. These groups were fed for 4, 8, 12, 16, 20 and 24 hr. per day respectively. Another group of ten were never allowed to feed after the last moult.2. Some of the figures for egg yield were high. Lice in the 24 hr. group were able to maintain a rate of ten eggs per day for 4−5 days at a time.3. No significant difference in longevity or rate of egg-laying was found to exist between the 12, 16, 20 and 24 hr. groups nor between the 4 and 8 hr. groups but a pronounced and significant difference exists between the 8 and 12 hr. groups. Below 12 hr. there is a sharp fall in longevity and rate of egg production. The unfed group all died, without laying, on the third day.4. The rate of laying as shown by the mode increases progressively with increase in time allowed daily for feeding.5. With regard to the mean eggs per louse the position is less clear. It is felt that the 24 hr. group may differ significantly from the 12, 16 and 20 hr. groups but this is uncertain.

scholarly journals Oral Microbiome Dysbiosis Is Associated With Symptoms Severity and Local Immune/Inflammatory Response in COVID-19 Patients: A Cross-Sectional Study

2021 ◽  
Vol 12 ◽  
Author(s):  
Irene Soffritti ◽  
Maria D’Accolti ◽  
Chiara Fabbri ◽  
Angela Passaro ◽  
Roberto Manfredini ◽  
...  
Keyword(s):  
Immune Response ◽  
Microbial Community ◽  
Virus Replication ◽  
Vaccine Development ◽  
Oral Bacteria ◽  
The Body ◽  
Oral Microbiome ◽  
Local Inflammation ◽  
Viral Origin ◽  
Oral Rinse

The human oral microbiome (HOM) is the second largest microbial community after the gut and can impact the onset and progression of several localized and systemic diseases, including those of viral origin, especially for viruses entering the body via the oropharynx. However, this important aspect has not been clarified for the new pandemic human coronavirus SARS-CoV-2, causing COVID-19 disease, despite it being one of the many respiratory viruses having the oropharynx as the primary site of replication. In particular, no data are available about the non-bacterial components of the HOM (fungi, viruses), which instead has been shown to be crucial for other diseases. Consistent with this, this study aimed to define the HOM in COVID-19 patients, to evidence any association between its profile and the clinical disease. Seventy-five oral rinse samples were analyzed by Whole Genome Sequencing (WGS) to simultaneously identify oral bacteria, fungi, and viruses. To correlate the HOM profile with local virus replication, the SARS-CoV-2 amount in the oral cavity was quantified by digital droplet PCR. Moreover, local inflammation and secretory immune response were also assessed, respectively by measuring the local release of pro-inflammatory cytokines (L-6, IL-17, TNFα, and GM-CSF) and the production of secretory immunoglobulins A (sIgA). The results showed the presence of oral dysbiosis in COVID-19 patients compared to matched controls, with significantly decreased alpha-diversity value and lower species richness in COVID-19 subjects. Notably, oral dysbiosis correlated with symptom severity (p = 0.006), and increased local inflammation (p &lt; 0.01). In parallel, a decreased mucosal sIgA response was observed in more severely symptomatic patients (p = 0.02), suggesting that local immune response is important in the early control of virus infection and that its correct development is influenced by the HOM profile. In conclusion, the data presented here suggest that the HOM profile may be important in defining the individual susceptibility to SARS-CoV-2 infection, facilitating inflammation and virus replication, or rather, inducing a protective IgA response. Although it is not possible to determine whether the alteration in the microbial community is the cause or effect of the SARS-CoV-2 replication, these parameters may be considered as markers for personalized therapy and vaccine development.

scholarly journals The Mechanism of Stimulating and Mobilizing the Immune System Enhancing the Anti-Tumor Immunity

2021 ◽  
Vol 12 ◽  
Author(s):  
Zhengguo Wu ◽  
Shang Li ◽  
Xiao Zhu
Keyword(s):  
Immune Response ◽  
Immune System ◽  
Tumor Microenvironment ◽  
Cancer Immunotherapy ◽  
Tumor Immunity ◽  
Checkpoint Inhibitors ◽  
The Body ◽  
Research Progress ◽  
Effective Population ◽  
Cell Components

Cancer immunotherapy is a kind of therapy that can control and eliminate tumors by restarting and maintaining the tumor-immune cycle and restoring the body’s normal anti-tumor immune response. Although immunotherapy has great potential, it is currently only applicable to patients with certain types of tumors, such as melanoma, lung cancer, and cancer with high mutation load and microsatellite instability, and even in these types of tumors, immunotherapy is not effective for all patients. In order to enhance the effectiveness of tumor immunotherapy, this article reviews the research progress of tumor microenvironment immunotherapy, and studies the mechanism of stimulating and mobilizing immune system to enhance anti-tumor immunity. In this review, we focused on immunotherapy against tumor microenvironment (TME) and discussed the important research progress. TME is the environment for the survival and development of tumor cells, which is composed of cell components and non-cell components; immunotherapy for TME by stimulating or mobilizing the immune system of the body, enhancing the anti-tumor immunity. The checkpoint inhibitors can effectively block the inhibitory immunoregulation, indirectly strengthen the anti-tumor immune response and improve the effect of immunotherapy. We also found the checkpoint inhibitors have brought great changes to the treatment model of advanced tumors, but the clinical treatment results show great individual differences. Based on the close attention to the future development trend of immunotherapy, this study summarized the latest progress of immunotherapy and pointed out a new direction. To study the mechanism of stimulating and mobilizing the immune system to enhance anti-tumor immunity can provide new opportunities for cancer treatment, expand the clinical application scope and effective population of cancer immunotherapy, and improve the survival rate of cancer patients.

scholarly journals THE BIOLOGICAL SIGNIFICANCE OF SELENIUM AND ITS PLACE IN RNA VIRAL DISEASES

2020 ◽  
Vol 21 (4) ◽  
pp. 21-31
Author(s):  
T.M. Guseynov ◽  
◽  
R.T. Guliyeva ◽  
F.R. Yakhyayeva ◽  
◽  
...  
Keyword(s):  
Oxidative Stress ◽  
Immune Response ◽  
Viral Infections ◽  
Biological Significance ◽  
The Body ◽  
Viral Diseases ◽  
Essential Trace Element ◽  
Regulatory Processes ◽  
P Protein ◽  
Almost All

ABSTRACT. Selenium as an essential trace element takes part in the regulation of many vital processes. This is realized with the help of over 25 selenoproteins that affect oxidative stress, immune response, hormonal metabolism, cognitive function, etc. Recently (in the next 30 - 40 years), there have been reports of the effect on viral infections, which have now become widespread. It turned out that almost all RNA viruses are selenium-dependent objects, that is, their genome contains the codes of the most important selenium containing proteins, including such as glutathione peroxidase, thioredoxinreductase, selenium-P protein, etc. Their synthesis during the development of a viral infection at the expense of the host leads to a weakening of the synthesis of the body's own intracellular selenium proteins, which contributes to the development of oxidative stress and a failure of the immune response. And this leads to the devastation of the selenium depot of the body, intended for the synthesis of its selenium proteins, which participate in vital regulatory processes. This circumstance determines, to replenish the body's resources with selenium, the expediency of using selenium-containing pharmacopoeia preparations as adjuvant in the treatment of RNA viral infections.

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