You need to read “The Very Lonely Firefly,” a story book delighting children of all ages by Eric Carle (1) to get the answer. In the mean time, you can read this article to have better insight into the enchanting world of the firefly. Are they just a pleasure to our eyes, during their short lives in the summer, or do they live on in children’s books?

Fireflies, or lightning bugs, belong to the Lampyridae family. There are thousands of firefly species all over the world and none of them are actually flies. Then what are they? Well, they are beetles, who get the names “firefly” and “lightning bug” because of the flashes of light emanating from their bodies, a process called bioluminescence (2). This “cold light” does not heat up or burn its producer through infrared or ultraviolet frequencies, and is formed by the action of an enzyme called luciferase in the lower abdomen of the firefly. It may be yellow, green, or pale red, with wavelengths from 510 to 670 nanometers. The enzyme luciferase acts on the luciferin, in the presence of magnesium ions, ATP, and oxygen to produce light (3). According to Vieira et al., 2012, in the Journal of Photochemistry and Photobiology, the firefly’s luciferase is the most important and studied bioluminescence system in scientific research(4). The firefly luciferase was cloned and isolated for the purpose of constructing bioassay systems in the late 1980s (5). Since then, due to very interesting characteristics, this system has been used in numerous biomedical, pharmaceutical and bioanalytical applications (4).

In biomedical research, the ability to visualize a biological process is very important because it offers the most direct method to support or disprove any scientific claim (6). Therefore, firefly luciferase is very desirable as a reporter in this area. Typically, the luciferase gene is cloned with a DNA sequence of interest into cells and then the cells are assayed by measuring its bioluminescence. Fusing a protein with luciferase is like putting a reflective vest on a cyclist in the dark to be able to watch him. Because the firefly luciferase lights up, it helps screening for chemical biology and drug discovery applications in academia and the pharmaceutical industry (5). For example, the firefly luciferase gene was used as a reporter to screen tumor-specific promoters in lung cancer (7). Another example showing how beneficial the firefly is for scientific research is a rapid in vivo (Latin for within the living) assessment of drug efficacy against Mycobacterium tuberculosis, which is the causative agent of most cases of tuberculosis, using an improved firefly luciferase (8). In this study, Andreu et al., 2013, used a Mycobacterium tuberculosis strain carrying a red-shifted derivative of the firefly luciferase gene to infect mice, and they monitored disease progression in living animals by bioluminescence imaging before and after treatment with a frontline anti-tuberculosis drug. Furthermore, firefly luciferase was used in a research about anti-malaria drugs, an illness which affects about 5% of the world’s population and brings a death toll of 0.5–2.5 million each year (9).

Firefly luciferase is not only used in biomedical research, but also in molecular plant biology. In the early ’90s, plant scientists were already able to show the bioluminescence of a promoter fragment fused to the firefly luciferase gene and its regulation by phytochrome (a pigment that plants use to detect light) and the circadian clock (a roughly 24 hour cycle in the physiological processes of living beings) (10) in plants. Some examples for the great usage of this system among many others include a firefly luciferase complementation assay that was used to reveal the interacting partners of Open Stomata 1 protein, which is critical for plant drought responses in Brassica oleracea (cabbage) (11) and the characterization of the promoter region of an important gene encoding a copper chaperone for the copper/zinc superoxide dismutase that is involved in oxidative stress protection of the potato plant (12).

Scientists have found many ways to use the firefly light, but what is the function of it for its real owner? Marc Branham, an assistant professor in the department of entomology and nematology at the University of Florida, explains. “Fireflies seem to flash light for a variety of reasons. The larvae produce short glows and are primarily active at night, even though many species are subterranean (underground) or semi-aquatic. Fireflies produce defensive steroids in their bodies that make them unpalatable to predators. Larvae use their glows as warning displays to communicate their distastefulness. As adults, many fireflies have flash patterns distinctive to their species and use them to identify other members of their species as well as to discriminate between members of the opposite sex. Several studies have shown that female fireflies choose mates depending upon specific male flash pattern characteristics. Higher male flash rates, as well as increased flash intensity, have been shown to be more attractive to females in two different firefly species (13).”

Are there other creatures like fireflies producing light? “Besides fireflies, many other organisms, especially marine creatures, use bioluminescence for sexual selection, attracting prey and as a means of camouflage, and it has been estimated that about 90 percent of deep-sea animals are bioluminescent, according to the Scripps Institution of Oceanography,” says Remy Melina, a staff writer for “Life’s Little Mysteries.”(14)

A firefly’s glow is a theme of summer nights, romantic poems, and childhood adventures and books. However, when you enjoy a firework show done by fireflies next time, please look at them more carefully by thinking that they have more than that to offer humanity, including thrilling scientific inventions done with just a single protein from them. Who knows what else they have waiting to be discovered by us? How amazing it is that, like everything else created on earth, a firefly is also a very precious art piece decorated with intricate features, and even though it is very tiny, its service to humanity is, in many ways, enormous.

References

http://www.barnesandnoble.com/sample/read/9780399227745
National Wildlife Federation
http://en.wikipedia.org/wiki/Firefly
Vieira J, Pinto da Silva L, Esteves da Silva JC (2012) Advances in the knowledge of light emission by firefly luciferin and oxyluciferin. J Photochem Photobiol B. 117:33-9.
Thorne N, Inglese J, Auld DS (2010) Illuminating insights into firefly luciferase and other bioluminescent reporters used in chemical biology. Chem Biol. 17(6):646-57>
Brogan J, Li F, Li W, He Z, Huang Q, Li CY (2012) Imaging molecular pathways: reporter genes Radiat Res. 177(4):508-13.
Xu R, Guo LJ, Xin J, Li WM, Gao Y, Zheng YX, Guo YH, Lin YJ, Xie YH, Wu YQ, Xu RA (2013) Luciferase assay to screen tumour-specific promoters in lung cancer.Asian Pac J Cancer Prev. 14(11):6557-62.
Andreu N, Zelmer A, Sampson SL, Ikeh M, Bancroft GJ, Schaible UE, Wiles S, Robertson BD (2013) Rapid in vivo assessment of drug efficacy against Mycobacterium tuberculosis using an improved firefly luciferase. J Antimicrob Chemother. 68(9):2118-27.
Che P, Cui L, Kutsch O, Cui L, Li Q (2012) Validating a firefly luciferase-based high-throughput screening assay for antimalarial drug discovery. Assay Drug Dev Technol. 10(1):61-8.
Millar AJ, Short SR, Chua NH, Kay SA (1992) A novel circadian phenotype based on firefly luciferase expression in transgenic plants. Plant Cell.4(9):1075-87.
Wang M, Yuan F, Hao H, Zhang Y, Zhao H, Guo A, Hu J, Zhou X, Xie CG (2013) BolOST1, an ortholog of Open Stomata 1 with alternative splicing products in Brassica oleracea, positively modulates drought responses in plants. Biochem Biophys Res Commun. 442(3-4):214-20.
Trindade LM, Horvath BM, Bergervoet MJ, Visser RG (2003) Isolation of a gene encoding a copper chaperone for the copper/zinc superoxide dismutase and characterization of its promoter in potato. Plant Physiol. 133(2):618-29.
http://www.scientificamerican.com/article/how-and-why-do-fireflies/
http://www.livescience.com/32677-what-makes-fireflies-light-up.html

The problem of pulmonary tuberculosis in pregnancy has attracted the attention of doctors for many years and it is still a current issue. Modern researchers and physicians divide tuberculosis into several independent problems which have difficult solutions. On the one hand, there is the influence of tuberculosis on the course of pregnancy and child delivery as well as on the health of a mother and her child. On the other hand, there is the influence of pregnancy and childbirth, the puerperal period and lactation on the course and progress of tuberculosis.

Research on how pregnancy influences the course of tuberculosis has been carried out for many years. Even in the oldest available documents we can find instructions for “personal precautions” and preventative measures against tuberculosis, as well as thoughts about pregnancy and tuberculosis. In 1400 BC the Law of Manu from ancient India prohibited marriages to girls from families with tuberculosis. In different world religions, including Islam and Christianity, there are special restrictions concerning people who suffer from this illness.

In ancient times Hippocrates and Galen taught that pregnancy has a positive influence on the function of lungs. But the Islamic doctors, Arabian as well as Spanish, of the Cordoba Caliphate considered that the blessed process of pregnancy must not be complicated by pulmonary diseases.

With time European medical science changed its point of view. From the second part of the 17th century until the beginning of the 19th century doctors considered that pregnancy had a bad effect on the course of tuberculosis, but then the situation, for some reason, changed. Doctors began to think that pregnancy had a good influence on lung diseases. They even started to advise girls who were susceptible to tuberculosis to marry. Time passed and doctors began to change their opinion on tuberculosis in pregnancy and the extremes in views became less obvious. This happened due to the introduction of an artificial pneumothorax into the treatment of tuberculosis.

Since then the third period in the understanding of the relationship between pregnancy and tuberculosis has begun. The opinion about the course of tuberculosis in pregnant women has changed due to the successful therapy of tuberculosis with the help of the artificial pneumothorax.

During the gestation period, all the organs and tissues of the entire organism experience an increased load, as they are trying to satisfy both their own needs and that of the developing fetus. These morphological and functional changes do not lead to any pathological state in the mother if she is healthy and her course of pregnancy is normal. If the woman’s organism has been weakened by a chronic immunodeficiency due to poor environmental conditions or if she has a tuberculosis process in her organism, then functional changes and tissue dystrophies can develop in her nervous system which will lead to metabolic disorders. Changes in ergasia caused by pregnancy and connected with changes in higher nervous activity, as well as with endocrine reorganization, can influence the development and the course of the tubercular process.

Before penicillin was discovered, pregnancy usually led to the progression of the disease and in many cases even ended fatally. Nowadays due to the use of effective antituberculous medicines the attitude towards possible pregnancy of women who have active tuberculosis has considerably changed.

Tuberculosis in a pregnant woman usually starts in an acute form; at this stage infiltrative forms of the disease with necrogenic and bacterioexcretion prevail, often combined with exudative pleurisy, trachea, larynx and bronchi lesions.

Frequent consecutive pregnancies have a negative effect on the state of women who suffer from tuberculosis; they weaken the organism and can cause the recrudescence of the tuberculosis process. This is very typical of many families in poor Asian and African countries. More than half of all pregnant women suffering from an active form of tuberculosis experience a progressive iron deficiency anemia during the first three months of pregnancy and in the second trimester of pregnancy this can be observed in almost all patients. Malaria is also widespread in Asian and African countries that are situated to the south of Sahara and are the second reason for iron deficiency anemia.

According to modern views, one of the reasons for the recrudescence of the tubercular process during pregnancy is an irregular or non-systematic treatment of this illness or the absence of any treatment at all. The recrudescence of the process observed in those suffering from destructive pulmonary tuberculosis is caused by the severity of the illness itself when new conditions for the organism occur. In this case, pregnancy begins against the background of an advanced chronic immune deficiency. At the same time, due to the feto-placental complex operation, functional changes in the nervous, respiratory, cardiovascular and urinary systems, as well as hormonal changes, in the organism of a pregnant woman take place.

Moreover, the development of the fetal skeleton requires calcium which is absorbed not only via the blood of the mother, but also from the healed niduses of tuberculosis and as a result, the progression of a specific process can appear.

The reactivation of the tubercular process happens due to a decrease in the responsiveness of the organism and because of an increase in the activity of the reproductive hormones and the loosening of the connective tissues which are physiologically involved in pregnancy. The amount of plasma and extra vascular fluid increases. Due to these changes, a swelling and loosening in the inactive tubercular niduses with the mycobacteria of tuberculosis can appear. And loosening, in its turn, enables a lymphohematogenous spread of mycobacteria.

In addition to these, the delivery of a child leads to a speedy reorganization of all the functions of the organism; lactation and nursing in their turn are combined with an increased loss daily of nutritious matters and a large amount of protein and fats. In case of destructive pulmonary tuberculosis, due to the fact that the diaphragm descends (resulting in the abdominal decompression ceasing to have a therapeutic action of pneumoperitoneum) bronchogenic dissemination appears in the unaffected parts of the lungs.

A specific active process can be observed in women belonging to the high-risk group in connection with tuberculosis. The high-risk group combines women who have recently suffered from tuberculosis (less than one year after treatment), those who have just been operated on for a tuberculosis connected illness (less than one year), women with tuberculosis of different localizations younger than 20 years (for Asia and Africa) and those older than 35 years (for Europe and the USA), those with widespread forms of the tubercular process withstanding its stage, women who have had contact with people discharging bacteria or people suffering from tuberculosis but not discharging bacteria, and also those who have coexisting illnesses (diabetes, chronic nonspecific pulmonary illnesses, problems with kidneys, stomach and duodenum ulcer), and also women who use alcohol, narcotics, those who smoke and lead asocial ways of life. In these cases, the women must be properly examined during the gestation period, including X-rays.

Treatment of tuberculosis during pregnancy

All other conditions being equal, the timely detection of active tuberculosis during pregnancy allows doctors to provide a full course of treatment, allowing the woman to recover and give birth to a healthy child. Untreated active tuberculosis of the mother is much more dangerous for the fetus than anti-tuberculosis chemotherapy.

Special attention must be paid to healthy women who are in contact with bacillary patients. Quite often these women might undergo active tuberculosis for the first time during pregnancy or after the delivery itself.

In the pre-penicillin era the recrudescence of the tubercular process during pregnancy and after the delivery proceeded in an acute form with frank infiltrative changes, a necrogenic process, bloody expectoration and very often a generalization of the process. Nowadays, the clinical outlook for complications and the recrudescence of tuberculosis against the background of pregnancy is less gloomy. It more resembles the toxicosis of pregnancy or respiratory diseases.

While examining a patient, special attention must be paid to chest problems like moist or dry coughs, bloody expectoration, pain in the chest and shortness of breath. If the patient coughs with expectoration for 2 weeks then she must be examined for mycobacteria with the usage of a microscopic technique.

Another syndrome, which is also very important, is a complex of intoxication symptoms (weakness, hidrosis, anorexia, weight loss, long-lasting low grade fever and hyperirritability) which need to be detected to discover the reason for their development. While examining the anamnesis of a pregnant woman it is necessary to learn if she has ever suffered from tuberculosis before, if she has had any possible contacts with infected people, whether there are cases of tuberculosis or concomitant diseases in her family as all of these can be very useful for the verification of tuberculosis.

When active pulmonary tuberculosis is suspected an X-ray examination is necessary. When the chest is in frontal projection, the X-ray exposure of the fetus is 10 times lower than that of its mother (with compulsory use of a protective apron). Examination of the cough expectoration for the presence of tubercular mycobacteria is one of the easiest, most effective and informative diagnostic methods.

Chemotherapy, which destroys the tubercle bacillus that spread in the organism, plays a leading role in the variety of methods for tuberculosis treatment. By reducing the population of bacteria, chemotherapy supports the healing process, the dispersion of inflammatory changes, the closing of caverns, the encapsulation of the remaining loci as well as preventing the development of sclerosis. When the patient suffers from tuberculosis, the healing processes are very slow; the first stage of the recovery process of mycobacteria ceases and only after some months, in the case of a successful treatment of tuberculosis, does the healing process finish.

The necessary treatment of pregnant women who suffer from tuberculosis must start as soon as the diagnosis has been made. Chemotherapy implies taking antibacterial medicines (isoniaside, rifampicin, pyrazinamide, ethambutol, ethionamide and etc.) in different combinations. The choice of this or that combination depends on the stage of the disease as well as on any undesirable reactions to the medicines prescribed.

The treatment of tuberculosis (if there are indications) continues during the entire pregnancy and lactation period. In particular, patients with tuberculosis that has been diagnosed during the pregnancy are in need of treatment. When there is a systematic treatment, up to the moment of delivery and in the puerperal period, positive clinicoradiologic dynamics can be observed regarding the specific inflammation (stoppage of bacterioexcretion, closing of caverns, dispersion of loci, infiltration and exudate). Patients who reject treatment during the process of pregnancy suffer from an advancement of the illness.

Transplacental infection of the fetus with tuberculosis almost never occurs, but the baby can be infected from the mother in the puerperal period. There is also a possibility of contamination during delivery, but this is a rare occurrence.. God truly protects the innocent!

Permission to breast feed must be given by a joint resolution of an obstetrician, a pediatrician, and a specialist of tuberculosis taking into account the state of a woman and the form and the stage of the tubercular process. Overall precautionary measures must be taken (a nonbacterial mask of 5-6 layers covering the nose and the mouth, a kerchief covering the head and thoroughly washed hands).

A bacteriological study of the breast milk of women who suffer from tuberculosis shows that typical mycobacteria rarely vegetates (no more than 0.33%). Human milk has the ability to suppress the development of the mycobacteria of tuberculosis. This must be connected with the rich spectrum of ferments, immunoglobulins, cellular elements, macro-phages, the complement system, interferon and other factors of nonspecific protection which human milk contains.

The contraindications for nursing are as follows: tuberculosis of the lactiferous gland, an acute form of tuberculosis, active pulmonary tuberculosis with bacterioexcretion, active tuberculosis of any organs detected at the end of the pregnancy or after the delivery, and recrudescence of tuberculosis during the pregnancy. Children born to such mothers are immediately isolated after their birth and bottle fed, they are vaccinated and stay in the hospital for 6 weeks if possible (the minimum period for compulsory postvaccinal isolation).

Thus the tubercular process in the lungs, especially an active one, will have a negative influence on pregnancy and delivery. Babies born to such mothers belong to a high-risk group as far as the possibility of neonatal pathology and antenatal death of the fetus are regarded. Women with pulmonary tuberculosis must undergo regular consultations with both an obstetrician-gynecologist and a phthisiologist from the very early stages of their pregnancy. They must also receive special treatment until all the signs of active tuberculosis have been eliminated.