Sunday, October 30, 2011

Beijing strains: New strain of tuberculosis linked to travel

By Syed Akbar
Hyderabad:  It may sound strange, but rapid growth in
information technology and frequent travel by software experts is
affecting the tuberculosis/HIV control programme in the country.
Individuals, particularly youngsters, who travel frequently across cities
are in a way helping the spread of a new strain of tuberculosis which is
more dangerous than the native ancient Indian strains, according to a
research study by the city-based Centre for DNA Fingerprinting and
Diagnostics and Ondokuz Mayis University Medical School of Turkey.
Transmission of "Beijing strains" of TB is facilitated with "recent
economic activity due to a boom in the information technology  and
communication sectors, where affordable air-travel has facilitated
frequent movement of especially younger population, across cities," the
study pointed out.
The spread of Beijing strains is slow but gradual and health planners
and experts fear that they will "out-compete" the ancestral types found
in India for over 10,000 years. The Indian native strains are less
virulent and docile as compared with the Beijing strains. And this is a
troubling news for health planners.
"The outcome could be hastened as India is witnessing a steep rise in
the number of human immunodeficiency virus cases," said Dr Niyaz
Ahmad of the CDFD and Hakan Leblebicioglue of OMUM School in
the study published in BMC Genetics, a prestigious international
scientific journal.
The study warned that synergy of TB, lead predominantly by the
Beijing strains, with HIV, threatens a series of outbreaks in several
years to come. "With fast spreading HIV, local advantages due to
ancestral bacilli, in terms of adaptation, and possibly `reduced
virulence' might be ruined. HIV through depleting the host immune
cells disregards any such advantages".
India is long known to harbour reservoirs of the ancestral TB strains,
which continue to predominate throughout the population. The TB
bacteria, M. tuberculosis is a millennia old pestilence that continues to
trouble people in the country. India also has TB bacteria diversity.
Stating that the ancestral strains bear seemingly important benefits for
the TB control programs in India, the study noted that "more
importantly, as a result of their adaptive evolution, the pathology
triggered by them may not be lethal. The Indian strains disseminate less
rapidly than the modern types like Beijing strains.
"Although Beijing strains are not an immediate threat, there is a danger
that they might predominate in due course if their dissemination
dynamics change with enhanced HIV transmission," the scientists said.
Of late the Beijing strains have been reported in different parts of the
country with Mumbai reporting as high as 30 per cent of the total TB
cases.
"It has been widely believed that India with its vast human resource in
healthcare, with DOTS coverage penetrating almost countrywide, and a
large national TB control program, is all set to tackle the pestilence. We
caution, to prepare for the threat of institutionalised outbreaks
perpetuated by newly emerging and expanding strains in synergy with
HIV, that is probably looming large," they cautioned.

A little addition of lemon juice, salt and pepper to green salad will help prevent cancer

Syed Akbar
Hyderabad: A little addition of lemon juice, salt and pepper to
green salad will help prevent cancer by increasing the anti-oxidant
activity in the body.
A research study by the city-based National Institute of Nutrition
showed that green salad prepared with lemon, salt and pepper had the
highest anti-oxidant activity among vegetable salads prepared without
these ingredients. Addition of legume sprouts to the salad will produce
the best green salad that will prevent cancer.
"Addition of lemon juice and powdered black pepper has no adverse
effect on the anti-oxidant activity of the salad prepared with legume
sprouts. In fact, the recipes developed has at least as much anti-oxidant
activity as the legume sprout per se. Indeed, the anti-oxidant activity of
salad prepared with green gram sprouts with lemon, salt and pepper
was the highest among the different salad recipes tested and the one
prepared from Bengal gram sprouts was the next best," the study
pointed out.
The NIN took up the study to generate data base on the antioxidant
properties of plant foods commonly consumed by the Indian
population.
As the sprouted legumes had the highest anti-oxidant activity among all
the processed foods studies, the NIN prepared a number of salads
using the sprouts of green gram, Bengal gram and moth beans in an
attempt to develop recipes rich in anti-oxidant activity.
In all 17 different kinds of sprouted legume salads were prepared using
different permutations and combinations of different sprouts and
vegetables. The sensory evaluation of these recipes was done by 40
normal healthy, adult, human volunteers. In general all the recipes had
comparable scores for appearance, colour, flavour, texture and taste and
their overall quality and acceptability were good.
Traditional legume sprout salad recipes had significantly lower anti-
oxidant activity than the legume sprouts per se and this was observed to
be due to the presence in them of low antioxidant foods such as
capsicum, cucumber and carrots.
"Removal of these low anti-oxidant activity foods from the recipes
improved the anti-oxidant activity of the recipe. But the AOA of such
recipes were still lower than that of legume sprouts. However, addition
of more of relatively AOA rich foods such as sprouts of groundnuts
and mustard seeds did not improve the AOA of the recipe any further.
But addition of lemon, salt and pepper increased the anti-oxidant
activity," it pointed out.

Saturday, October 29, 2011

Sambar prevents growth of cancerous cells in the body

By Syed Akbar
Hyderabad: The mouth-watering south Indian sambar has several
anti-oxidant properties which prevent the
growth of cancerous cells in the body.
The special ingredients that go into the preparation of this south Indian
patented dish help in easy digestion, provide
the much-needed energy and boost the immune system. They are also
anti-carcinogenic in nature and prevent the
development of cancer.
The Union Ministry of Health and Family Welfare, in association with the
Public Health Foundation of India, has
launched a campaign to promote traditional Indian foods as part of its
"healthy India" programme. The campaign
highlights the importance of south Indian sambar in the over all diet
balance of an individual and prevention of a
variety of diseases including carcinomas.
"Vegetables that are incorporated in dal preparations like sambar increase
the glycemic index of food and provide a
variety of nutrients and anti-oxidants. This also ensures that a number of
vegetables get consumed everyday, as
sambar is an essential food item consumed by most households," the MoHFW
points out in its campaign.
Drumsticks, onions, garlic, asafoetida, bhendi, brinjal and bottle gourd
are essential ingredients of sambar and each
of them have their own medicinal and anti-oxidant properties.
Any item that increases the glycemic index of food keeps the body healthy
and strong and free from diseases or
major health complications. A balanced glycemic index means control over
diabetes, weight and blood lipids and
improved body sensitivity to insulin and fast re-fuel of carbohydrate
stores after exercise. Sambar is the ideal kitchen
preparation to maintain the glycemic index of food.
Since sambar is prepared with less oil, it does not give much calories to
the body. Consumption of sambar and
traditional chutneys prepared from special spices provide additional
health benefits by virtue of micronutrients, anti-
oxidants and vitamins present in them in sufficiently large quantities.
"Healthy eating habits and increased physical activity alone can reduce
the risk of developing diabetes by 58 per
cent, high blood pressure by 66 per cent and heart attacks and stroke by
40-60 per cent," it points out.

Docodont: A new mammal of docodont group discovered: It is 150 million years old fossil

By Syed Akbar
Hyderabad: A new mammal belonging to the docodont group has
been discovered from the Kota Formation at Paikasigudem village in
Adilabad district.
The fossilised mammal is at least 150 million years old and this is the first
time that a docodont mammal has been found from the Southern Hemisphere.
Docodont mammals are primitive animals found during the Jurassic period
along with dinosaurs and they are considered to be the final line of
mammalian old-timers.
Scientists the world over thought that docodonts were present only in North
America and England as the remains of several species of docodont mammals
were excavated only from these parts in the Northern Hemisphere. The latest
discovery showed the presence of such animals in Southern Hemisphere too.
"It is now quite clear that docodonts were widely spread across the earth,"
says GVR Prasad, who discovered the animal remains.
The new animal has been named Gondtherium dattai in honour of the local
Gond tribal population. The find from Adilabad is of paramount importance
as it testifies to the presence of typical docodont mammals in Gondwanan
continents.
The Kota Formation, which dates back to late middle Jurassic period (150
million years ago) and lower Cretaceous period (65 million years), had
earlier
yielded mammal groups like symmetrodontan and eutriconodontan.
Bulk screen-washing of the clays and mud stones found in Kota Formation
produced an isolated mammalian upper premolar. A detailed study of the
tooth led to the discovery of the new mammal genius Gondtherium.
The premolar tooth has asymmetrical chewing/biting outline, two labial cusps
and other features very similar to the upper premolars of docodont mammals.
Detailed comparisons with the upper dentition of various known docodont
animals showed that the premolar pattern of the new specimen from Adilabad
was similar to Haldanodon, an animal found during the Mesozoic period.
The tooth of Gondtherium dattai differed from the upper molars of all known
docodont animals in having labial cusps with diverging tips that are
separated
by a broad notch. The enamel of the tooth was not preserved as also the
roots,
but from the broken dorsal surface it appeared that there were probably three
roots. The pulp chamber was widely open and had a smooth surface and
rounded edges as in permanent teeth.
Docodont mammals were earlier known only from the Upper Triassic,
Middle and Upper Jurassic, and Lower Cretaceous deposits of North America
and Europe, pointing to a typical Euramerican distribution for this group.
"The associated mammalian study helps us in reconstructing a generalised
paleobiogeographic scenario. The more recent discovery of Dyskritodon
from the Kota Formation first recorded from the Early Cretaceous of
Morocco, represents an example of faunal continuity across India and Africa.
The occurrence of closely related mammals in the Jurassic of India and Late
Triassic and Early Cretaceous of Africa, as well as Middle and Late Jurassic
of Europe points to biogeographic connections between these regions," he
points out in his study.
This is not surprising because paleogeographic maps show Europe in close
proximity of NW Africa and India adjacent to Africa in the Early/Middle
Jurassic. The cosmopolitan distribution of the Kota fauna has also been
corroborated by the non-mammalian vertebrate groups like ostracods and
charophytes.
Barapasaurus and Kotasaurus, sauropod dinosaurs from the Kota Formation,
and the Early Jurassic sauropod Vulcanodon of Zimbabwe appear to be
closely related to the Late Triassic sauropod Isanosaurus of Thailand.
"In view of this continuity of mammalian as well as non-mammalian animal
remains during the Jurassic and Early Cretaceous across Gondwanan
continents, it is predicted that early docodonts might have existed on other
southern continents as well," says Prasad.
The possible reasons for not finding Docodonts on the southern continents
until now are restricted occurrence of Jurassic continental sequences in this
part of the globe; low intensity sampling of the known deposits; and
taphonomic (decaying) factors.

XX maleness a rare syndrome


By Syed Akbar

It is a common knowledge that a person with XX chromosomes is a 
woman and the one with XY chromosomes is a man. The sex 
chromosomes XX determine the female sex of a foetus while XY 
determine the male sex of the unborn in the womb.
There are men with XX chromosomes but they do not have fully 
developed male genital organs. However, a team of scientists in 
Hyderabad recently came across with a XX man with normal genitals 
and complete masculinity. This is a very rare medical phenomenon.
The scientists' team at the Centre for Cellular and Molecular Biology 
conducted a research on this XX man with gene SRY-negative and 46 
chromosomes.
According to CCMB senior scientist Kumarasamy Thangaraj, XX 
maleness is a rare syndrome with a frequency of one in 20,000-25,000 
males. XX males exist in different clinical categories with ambiguous 
genitalia or partially to fully mature male genitalia, in combination with 
complete or incomplete masculinisation. But in the present study the 
team reported a case of SRY-negative XX male with complete 
masculinisation. The "man", however, was infertility and unable to 
conceive.
The patient had fully mature male genitalia with descended but small 
testes and no signs of undervirilisation. Polymerase chain reaction 
analysis for SRY (sex determining region Y gene) and other sex 
determination genes ZFY, amelogenin, AZFa, AZFb and AZFc as also 
other tests showed the absence of any Y-chromosome-derived material.
Genotyping with X-STR (short tandem repeat) of the chromosome 
ruled out the possibility of any deletion on X chromosome. 
"Development of the male phenotype in the absence of SRY probably 
resulted from the loss of function mutation in some unknown sex-
determining gene, which normally inhibits the male pathway, or from a 
gain of function mutation in a gene downstream to SRY in male 
pathway," Dr Thangaraj points out.
We all know that the presence or absence of Y chromosome, SRY gene 
in particular, determines the sex in human beings and other mammals. 
SRY is thought to direct the sex-determination pathway towards male 
development. The fortuitous finding of chromosomal rearrangements in 
association with a sex-reversed phenotype has led to the isolation of 
SRY gene. Careful genetic analysis of cases with abnormal sexual 
development, presented with chromosomal translocations or deletions/
duplications, has resulted in the identification of many genes playing 
role in sex determination, Dr Thangaraj says.
"Despite the identification of SRY almost 15 years ago, the pathway 
downstream to SRY remains largely unknown, although SOX9 and 
DAX1 have recently been proposed to function downstream to SRY 
gene in male sex-determination pathway," he adds.
According to the CCMB study, an increasing number of reports suggest 
that the male phenotype can develop even in the absence of SRY gene. 
Till date, many cases of XX males with or without SRY and apparently 
with no other Y-chromosome sequences have been reported.
Such persons exist in three clinical categories: XX males with normal 
genitalia; XX males with ambiguous genitalia; and XX true 
hermaphrodites with ovarian and testicular tissues.
"Based on the presence or absence of the Y-chromosome sequences, 
XX males can be divided into two categories. Approximately 90 per 
cent of the cases carry varying amount of the Y sequences due to an 
illegitimate recombination between X and Y chromosomes, whereas 10 
per cent do not have any Y-chromosome sequences. Most of the XX 
males with SRY have normal genitalia, whereas most SRY-negative 
cases have ambiguous genitalia," says Dr Thangaraj.
The cause (aetiology) of development of male phenotype in most of the 
SRY-negative 46,XX males (like the present case study) remains 
unexplained. 
He points out that development of the testis and normal male genitals in 
a significant number of SRY-negative 46,XX males gives clue to the 
existence of other autosomal or X-linked genes in the sex-determining 
pathway. Comprehensive genetic analysis of these cases may help to 
decipher new gene(s) involved in the sex-determining pathway.
A 34-year-old man attended the genetic clinic of the Institute of 
Reproductive Medicine, Kolkata, with complaints of infertility. His 
height was 156 cm and weight 64 kg. The patient had fully mature 
normal male genitalia with no symptom of undervirilisation.
The testicles were descended in the scrotum but small in size with 
volumes 4.8 ml and 5.1 ml (normal range 18-30 ml). Axillary (under 
arm) and pubic hairs were of normal pattern and density. Serum 
concentrations of reproductive hormones (LH and FSH) were elevated 
at 15.8 mIU/ml (normal range 2.0-14.0 mIU/ml) and 25.8 mIU/ml 
(normal range 1.5-12.0 mIU/ml), respectively. Testosterone hormones 
level was normal at 580 ng/dl (normal adult male range, 437-707 
ng/dl).
DNA was extracted from peripheral blood leukocytes of the patient, a 
normal fertile male and a female for analysis. Absence of PCR 
amplification of Y-STR markers further confirmed the lack of Y-
chromosome sequences in the patient DNA. X-STR analysis showed 
heterozygous alleles for 42 of 53 markers, suggesting the presence of 
two X chromosomes.
According to him, majority of the XX males carry SRY gene 
translocated to the X chromosome due to an illegitimate recombination 
between X and Y chromosomes. These patients are sterile males and 
usually have normal male genitalia.
Dr Thangaraj says XX males without SRY gene have ambiguous to 
normal genitalia, show incomplete to complete masculinisation and are 
infertile. The existence of SRY-negative males ruled out the prevailing 
notion that the mere presence of SRY determines maleness. The most 
common observation that the individuals with SRY are male shows that 
it is the presence or absence of a normal SRY gene which determines 
maleness, provided all downstream genes are functionally intact. 
In majority of the cases, XX maleness should result either from the loss 
of function mutations in a gene normally inhibiting testes formation in 
genotypic females or from the gain of function mutations in a gene 
downstream to SRY in testis determining pathway. The hypothetical 
gene may be X-linked or autosomal. If the gene is autosomal, the 
degree of the male phenotype will be dependent on the extent of the 
loss or gain of function in the mutant gene, he says.
"Because the present case had normal male phenotype, it should 
either be homozygous mutant for this hypothetical autosomal gene or 
a result of preferential inactivation of the normal copy of the X-linked 
heterozygous mutant gene," Dr Thangaraj concludes.