The history of fetal surgery features an absolute dependency upon the possibility of diagnosis before birth. Powerful new imaging methods, the techniques of sampling amniotic fluid and fetal tissue, and modern molecular genetics for the prenatal diagnosis of various congenital diseases have removed the veil of secrecy from the fetus. Even though most prenatally detected congenital malformations can be managed after maternal transport, a few simple anatomic defects require fetal surgery, albeit with predictably poor results. The understanding of intrauterine physiology and pathophysiology in several congenital malformations has been worked out in animal model study, and the natural history of congenital defects revealed by prenatal observations on human fetuses. Selection criteria for intrauterine intervention have been developed. Over the last two decades, surgical techniques for open and endoscopic fetal surgery have been defined and anesthesia and tocolysis for fetal surgery improved. As we enter the 21st century, this field of surgery will surely expand. (+info)
Prehistoric human colonization of India.
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Human colonization in India encompasses a span of at least half-a-million years and is divided into two broad periods, namely the prehistoric (before the emergence of writing) and the historic (after writing). The prehistoric period is divided into stone, bronze and iron ages. The stone age is further divided into palaeolithic, mesolithic and neolithic periods. As the name suggests, the technology in these periods was primarily based on stone. Economically, the palaeolithic and mesolithic periods represented a nomadic, hunting-gathering way of life, while the neolithic period represented a settled, food-producing way of life. Subsequently copper was introduced as a new material and this period was designated as the chalcolithic period. The invention of agriculture, which took place about 8000 years ago, brought about dramatic changes in the economy, technology and demography of human societies. Human habitat in the hunting-gathering stage was essentially on hilly, rocky and forested regions, which had ample wild plant and animal food resources. The introduction of agriculture saw it shifting to the alluvial plains which had fertile soil and perennial availability of water. Hills and forests, which had so far been areas of attraction, now turned into areas of isolation. Agriculture led to the emergence of villages and towns and brought with it the division of society into occupational groups. The first urbanization took place during the bronze age in the arid and semi-arid region of northwest India in the valleys of the Indus and the Saraswati rivers, the latter represented by the now dry Ghaggar-Hakra bed. This urbanization is known as the Indus or Harappan civilization which flourished during 3500-1500 B.C. The rest of India during this period was inhabited by neolithic and chalcolithic farmers and mesolithic hunter-gatherers. With the introduction of iron technology about 3000 years ago, the focus of development shifted eastward into the Indo-Gangetic divide and the Ganga valley. The location of the Mahabharata epic, which is set in the beginning of the first millennium B.C., is the Indo-Gangetic divide and the upper Ganga-Yamuna doab (land between two rivers). Iron technology enabled pioneering farmers to clear the dense and tangled forests of the middle and lower Ganga plains. The focus of development now shifted further eastward to eastern Uttar Pradesh and western Bihar which witnessed the events of the Ramayana epic and rise of the first political entities known as Mahajanapadas as also of Buddhism and Jainism. The second phase of urbanization of India, marked by trade, coinage, script and birth of the first Indian empire, namely Magadha, with its capital at Pataliputra (modern Patna) also took place in this region in the sixth century B.C. The imposition by Brahmin priests of the concepts of racial and ritual purity, pollution, restrictions on sharing of food, endogamy, anuloma (male of upper caste eligible to marry a female of lower caste) and pratiloma (female of upper caste ineligible to marry a male of lower caste) forms of marriage, karma (reaping the fruits of the actions of previous life in the present life), rebirth, varnashrama dharma (four stages of the expected hundred-year life span) and the sixteen sanskaras (ceremonies) on traditional occupational groups led to the birth of the caste system - a unique Indian phenomenon. As a consequence of the expansion of agriculture and loss of forests and wildlife, stone age hunter-gatherers were forced to assimilate themselves into larger agriculture-based rural and urban societies. However, some of them resisted this new economic mode. To this day they have persisted with their atavistic lifestyle, but have had to supplement their resources by producing craft items or providing entertainment to the rural population. (+info)
Ethnic populations of India as seen from an evolutionary perspective.
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It is now widely accepted that (i) modern humans, Homo sapiens sapiens, evolved in Africa, (ii) migrated out of Africa and replaced archaic humans in other parts of the world, and (iii) one of the first waves of out-of-Africa migration came into India. India, therefore, served as a major corridor for dispersal of modern humans. By studying variation at DNA level in contemporary human populations of India, we have provided evidence that mitochondrial DNA haplotypes based on RFLPs are strikingly similar across ethnic groups of India, consistent with the hypothesis that a small number of females entered India during the initial process of the peopling of India. We have also provided evidence that there may have been dispersal of humans from India to southeast Asia. In conjunction with haplotype data, nucleotide sequence data of a hypervariable segment (HVS-1) of the mitochondrial genome indicate that the ancestors of the present austro-asiatic tribal populations may have been the most ancient inhabitants of India. Based on Y-chromosomal RFLP and STRP data, we have also been able to trace footprints of human movements from west and central Asia into India. (+info)
Drug addiction. Part I. Psychoactive substances in the past and presence.
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Substances capable of changing the functions of the central nervous system are widely distributed in plant kingdom, and many of them were discovered by ancient food-gatherers at the dawn of humanity. In the Old World only a few substances producing euphoria or altered states of consciousness and having habit-forming properties are still widely used. They are the products of poppy (opium, morphine), hemp (hashish, marijuana), and of fermentation of various organic materials alkohol. This list has recently been joined by the psilocybin-containing mushrooms. The addiction-forming compounds originated in the New World and widely spread are tobacco (nicotine) and cocaine. In the 19th and 20th, century the development of medicinal chemistry resulted in several synthetic compounds, originally proposed as therapeutics, such as barbiturates, benzodiazepines and amphetamines. Due to legal problems, to avoid production of the substances already prohibited, many designer drugs were manufactured. In addition, several compounds were synthesized as recreational drugs. Also some compounds that were not regarded as drugs, such as aromatic hydrocarbons and other cleansing agents, as well as steroids were found to have properties of dangerous, habit-forming agents. The attitude of society and the pattern of use of psychoactive substances have changed with time, particularly in the last decades. The active principles are now more addictive because of concentration, purification, chemical modifications and the way of ingestion, which now favors most rapid transport to the central nervous system. The substance abuse approaches the level of global epidemics, and the recent usage of drugs of addition is also reviewed. (+info)
Phototherapy: from ancient Egypt to the new millennium.
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Phototherapy with ultraviolet light was widely and successfully used in the past for treatment of a variety of diseases. Phototherapy with visible light alone has no benefit except in the therapy and prophylaxis of unconjugated hyperbilirubinemia. For this purpose, radiation in the region of approximately 480 to 500 nm is most effective and radiation above approximately 550 nm is useless. The principle effect of the treatment is not photodegradation of bilirubin, but conversion of the pigment to structural isomers that are more polar and more readily excreted than the normal, more toxic "dark" form of the pigment. This, coupled with some photooxidation of bilirubin, diminishes the overall pool of bilirubin in the body and lowers plasma levels. In the future, phototherapy may be supplanted by pharmacologic treatment, but in the near future, the most likely advance will be the introduction of novel forms of light production and delivery. (+info)
A brief history of spa therapy.
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Bathing in thermal water has an impressive history and continuing popularity. In this paper a brief overview of the use of water in medicine over the centuries is given. (+info)
Enzymatic repair of selected cross-linked homoduplex molecules enhances nuclear gene rescue from Pompeii and Herculaneum remains.
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Ancient DNA (aDNA) samples extracted from the bone remains of six equids buried by the Vesuvius eruption in 79 AD were investigated to test pre-amplification and enzymatic repair procedures designed to enhance the rescue of nuclear genes. The extracts, which proved all positive for Equidae mtDNA amplification, proved positive only four times out of 18 when tested for single-copy Equidae nuclear genes (epsilon globin, p53 and gamma interferon). Pre-amplification did not change the number of retrieved aDNA sequences but 10 times out of 14 enzymatic repair restored the amplifiability of the genes analysed, proving that repair increases the rate of successful rescue from 22 to alpha(lambda)mu(omicron)sigma(tau) 80%. These findings support the hypothesis that some of these cross-linked aDNA molecules, which are not completely separated when DNA is extracted under denaturing conditions, become homoduplex substrates for Pol I and/or T4 ligase action upon renaturation. aDNA authenticity is proved by the homology of the nucleotide sequences of loci tested to the corresponding modern Equidae sequences. Data also indicate that cross-linked homoduplex molecules selected by denaturation of the extract are repaired without any chimera formation. The general features of aDNA amplification with and without denaturation and enzymatic repair are discussed. (+info)
Origins of cancer therapy.
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This is a brief overview of the development of cancer therapy with a focus on systemic therapy. The modern era of chemotherapy developed at Yale University Medical School during World War II, a fact that has been generally unrecognized until recently. The observations preceding and involved in the discovery of effective drugs for cancer seem particularly pertinent for this anniversary year. (+info)