|
C. S. Delmonte
Abstract
Many medical research teams continue to study
the wide range of human conditions influenced by the
structure and function of Z-DNA, for example, the
differentiation of fibre cells in the adult lens1, a pox
virus which complexes with Z-DNA2, the inhibition of
transcriptional activation3, a conserved family of Z-DNA
binding proteins4, the rôle of Z-DNA in the activity of the
hippocampus in the Alzheimer Brain5, an RNA deaminase has a
binding site for Z-DNA6, 7, and a human gene codes for the
protein dlm-1 which has a Z-DNA binding domain8.
Z-DNA-forming sites have been reported within the human
genome9. New Z-DNA duplexes are being currently reported10.
While the Z form has been assigned a left-handed helical
sense11, a central difficulty about the crystallographic
identification of Z‑form oligodeoxyribonucleotides and Z-DNA
as being uniformly left‑handed is the creation of a crucial
paradox. Highly regarded crystallographers, for example
Sasisekharan & Brahmachari12 , and Leslie et al.13, record
the complete conversion of the B to the Z form inside
semi-crystalline fibres under the very mild conditions of
humidity change alone. Likewise, Mahendrasingham et al.14
studied the transition of the B to the D form under
similarly mild conditions using time-lapse data recording. These crystallographers argue strongly from
the direct experimental evidence of a clear change in
well-defined diffraction patterns that the B, D and Z forms
must have the same helical handedness to effect such changes
from one polymorph to another inside semi-crystalline fibres
with high conversions, since only small structural changes
are conceivable in these circumstances. Much earlier,
Franklin & Gosling15 had reported the complete
interconversion of the A to and from the B form, and
likewise Marvin et al.16 had reported the conversion of form
B to C inside fibres with humidity change alone. Therefore,
if they have a uniform helical handedness along their whole
molecular lengths, A, B, C, D and Z‑DNA would all have the
same uniform helical handedness because these polymorphs are
all variously interconvertible inside solid fibres.
Now, Dickerson's group17,18 claims, from a study of a true
oligodeoxyribonucleotide crystal, that B‑DNA is
right‑handed. Rich's group11 have studied a crystalline
fragment, designated Z‑DNA, which they claim is
left‑handed. If the DNA polymorphs are claimed to each have
a uniform helical handedness along their whole molecular
lengths, and if the Z form fibre in vivo is claimed to have
the same handedness as the crystalline Z-DNA fragment (a
proposition which has never been directly established), it
would seem that at least one team of crystallographers must
be wrong. Either DNA fibres of the forms A, B, C, D & Z
have the same helical handedness as suggested by their
various, ready interconversions inside fibres, or the B and
Z polymorphs have opposite handedness as deduced from the
structural solutions derived from X-ray diffraction from
true crystals of their respective oligodeoxyribonucleotides
which are then extended to the structure of the high
polymer.
Full Article
The Effects of culture Conditions on biosurfactant activity of
Pseudomonas aeruginosa 181 using response surface methodology
AL-Araji Laith, R.N.Z.A. Rahman,, M. Basri, A.B. Salleh
Abstract
Response surface methodology (RSM) was
used to study interactive effects of the parameters (pH, stirring rate,
casamino acid concentration and incubation period) on the biosurfactants
activity. It was implied that the effect of any one parameter could not,
on its own, explain the outcome of the reaction without considering the
input of the other parameters. For this reason, experiments in this
following were performed to gain some insight into their combined
interactive effects. Within the experimental range studied, optimal
conditions for the biosurfactant
activity were predicted using the optimization function of the Design
Expert software. The actual biosurfactant activities by Pseudomonas
aeruginosa 181 were 28.43 dyne / cm for surface tension and 85%
Emulsification Index (E24).
Full Article
Manora Island Project: a model primary care project in Pakistan
Amin A. Muhammad Gadit
Abstract
This community based project
which was established in an island of Karachi-Pakistan is a unique
example of health care to a deprived community on a voluntary basis. It
involves a group of dedicated medical doctors and social workers
who surveyed a local community in the island with a population of
n=5000, administered a questionnaire to assess their current health
status along with the demographic information, provided on-site health
services and reassessed their health status twice with a yearly interval
and found that there was a significant decline in the morbidity of the
local residents. It was concluded that if such projects are replicated
nation-wide, the country’s health services will have tremendous
improvement.
Full Article
Using TreeNet for Identifying Management
Thresholds of Mantled Howling Monkeys' Habitat Preferences on Ometepe
Island, Nicaragua, on a Tree and Home Range Scale
Jesse N. Popp, Denise Neubauer, Lisa M. Paciulli, Falk Huettmann
Abstract
Numerous studies have been conducted on mantled howling monkeys (Alouatta
palliata). However, very few of the studies have dealt with
explicitly quantifying spatial and habitat preferences. Thus, the exact
used and unused habitats of howling monkeys remain neither fully
investigated nor quantified. Thus, crucial thresholds for science-based
sustainable management programs continue to be unknown. Therefore, in
this paper, the presence and absence of two howling monkey groups in
different forest types on the island of Ometepe, Nicaragua were
examined. Data were collected onseveral variables including the focal
animal's tree location and measurements of that tree. Thesedata were
linked with landscape features such as proximity to man-made and natural
edges. In orderto assess the generalizability and robustness of the
findings, the data were analyzed on two scales: (i) the trees the
monkeys used were compared to random (pseudo-absence) trees and (ii)
home rangeswere estimated based on the animals locations and compared to
unused (‘absence’) areas.Resource Selection Functions (RSFs), which are
widely utilized for comparing localities used by wildlife to unused
locations, were employed. The powerful TreeNet (Salford Systems Ltd.)
algorithm wasapplied to obtain the resource functions and thresholds.
The results indicate that tree Diameter at Breast Height (DBH) and its
derivatives were the most relevant variable explaining where the howling
monkeys occurred in the island forest habitats.This study uses a
powerful TreeNet algorithm to determine resource selection functions and
thresholds of the mantled howling monkey on two habitat scales in order
to contribute to their conservation.
Full Article
Moti Nissani, Donna Hoefler-Nissani
Abstract
To date, one investigation failed to find mirror
self-referential behavior in Asian elephants while two
others reported positive results, a contradiction which
could, among other things, be ascribed to the poor visual
acuity of elephants. To throw additional light on
these contradictory reports, the present study of mirror
self-referential behavior in two captive Asian elephants
bypasses the traditional mark test, relying instead on the
elephants’ response to a far more visually conspicuous
object, and on prior habituation to the presence of this
object in their enclosure. In this study, neither
elephant engaged in self-referential behavior in front of a
mirror. Our simple experimental paradigm could serve
as a more convenient alternative to the widely used
traditional mark test, could meet some methodological
objections which have been raised against the traditional
mark test, and could profitably augment the traditional test
in difficult or controversial cases.
Full
Article
Antimicrobial
activity and micropropagation of Peperomia tetraphylla
Ingelia White,
Lora Oshima,
Nelly D. Leswara
Abstract
Peperomia tetraphylla
(G. Forst.) Hook. & Arn. (Piperaceae) or ala ala wai nui kane is
a fleshy native Hawaiian herb reputed to cure feminine ailments in
traditional Hawaiian medicine. A preliminary study on its antimicrobial
activity, palatability and micropropagation techniques was conducted at
the University of Hawaii – Windward Community College from May to
December 2003. The entire plant, including stems, leaves and spikes was
ground in 99.9% methanol with mortar and pestle, and centrifuged for 10
minutes at maximum speed to obtain its supernatant. Various
concentrations in duplicates of crude methanolic extract of P.
tetraphylla were prepared for pour plate and agar diffusion tests
against Candida albicans, Escherichia coli and Staphylococcus
aureus. Extract concentrations of 125 mg/mL (1.25 mg /10 µL)
and 250 mg/mL (2.5 mg /10 µL)
influenced the microbial growth. A highly significant colony reduction
(72%) was shown in pour plates containing 125 mg/mL of extract for C.
albicans, 57% for E. coli and 30% for S. aureus. The
disks containing 2.5 mg /10 µL
extract in agar diffusion plates yielded a 33 mm inhibition zone for
C. albicans, 9 mm for E. coli and 10 mm for S. aureus.
This study suggests the possible use of P. tetraphylla for
treatment of vaginitis, cystitis and skin infections caused by those
microorganisms. The plant can be safely ingested as a food medicine. In
vitro culture of leaves, stems and seeds produced plantlets within 28 to
30 days. Full
Article
Possible deletion of a 245 bps polymorphic marker in breast cancer cells
(MCF-7)
AKM A.
Hussain, Brian H. Crawford, Nathan M. Jideama
Abstract
A
polymorphic biomarker gene with a nucleotide sequence of 245 bps was
isolated from normal human mammary epithelial cells (MCF-10A) by using
the DNA amplification fingerprinting (DAF) technique. This marker was
absent in human breast cancer cells (MCF-7). A Genbank database search
with this gene sequence revealed it had 100% homology with the
nucleotide sequence of human chromosome 4 (BAC RP11-451F20) (bps
1613220-161564) (Genbank account: AC093844.3). The nucleotide sequence
of the biomarker was translated using Genbank CDS (account gi |11387274
|sp |P55782| PPNK_BUCAI), and revealed that this gene codes for a
probable inorganic polyphosphate/ATP-NAD kinase. In order to evaluate
the effects that the 245 bps biomarker would have on the morphology of
MCF-7 cells, the MCF-7 cells were transfected with the 245 bps
biomarker. There were observable changes in the morphology of the
transfected cells. These changes included an increase in cell
elongation and a decrease in cell aggregation.
Full Article
Abstract
Introduction:Labisia
pumila var
alata
or as known among Malay women as Kacip Fatimah
(KF), has long being recognized for its medicinal value.
Recently, researches have demonstrated its estrogenic
activity. Ovariectomy (surgical menopause) is known to
cause weight gain and increase adiposity due to estrogen
deficiency.
Objective: This study was aimed to
investigate the effect of Labisia pumila consumption
and Estrogen Replacement Therapy (ERT)
on the
morphology of adipose tissue following ovariectomy.
Methodology: 6 months old female (Sprague Dawley)
rats were ovariectomized (bilaterally) under anesthesia
using the ventral approach and randomly divided into OVXC (ovariectomized
control), KF and ERT. KF and ERT received daily oral
treatment of water extract of Labisia pumila (17.5
mg/kg/day), and ERT (64.5 µg/kg/day) respectively for a
period of three months. A group of 9 normal rats was left
intact and used as normal control (NOR). Rats were
sacrificed by cervical dislocation and tissue samples from
abdominal fat were collected and fixed immediately either in
4% paraformaldehyde for electron microscopy or in 10%
formalin for light microscopy.
Results: Light
microscopy revealed hypertrophic growth (increase in the
size of adipocytes) as well as increasing vasculature of
adipose tissue in the OVX rats compared to the normal rats.
Transmission electron microscopy (TEM) revealed thickening
of the adipocyte membrane of the OVXC rats.
KF and
ERT-treatment were demonstrated to cause adipocytes
membranes' breakage as shown by the fragmentation of the
collagen bands. Conclusion: Results implied a
possible role for Labisia pumila var alata
in modulating postmenopausal adiposity through the
initiation of the lipolysis process in adipose tissue.
Full
Article|
Abstract
Source amnesia is an explicit memory (declarative) disorder,
particularly episodic, where source or contextual
information concerning facts is severely distorted and/or
unable to be recalled. This paper reviews the literature on
source amnesia, including memory distrust syndrome, and its
accepted correlation with the medial diencephalic system and
the temporal lobes, and the suggested linkage between the
frontal lobes, including special interest with the
prefrontal cortex. Posthypnotic induction was the first
presentation of source amnesia identified in the
literature. The Wisconsin Cart Sorting Test (WCST),
Positron Emission Topography (PET), Phonemic Verbal Fluency
Test, Stroop Color Word Interference Test, and explicit and
implicit memory tests are defined and linked to empirical
research on amnesiacs. Full
Article
Amin
A. Muhammad Gadit
Abstract
There has been an alarming increase in the incidence of
mental illness the world over. Individual countries are
struggling to address this issue in terms of professional
resources, available facilities and economic burden. Both
the developing and the developed countries are facing the
dilemma under the current scenario of increasing mental
health morbidity.In order to assess the situation a
comparison is made between a developed and a developing
country in terms of the population, number of psychiatric
beds, morbidity patterns, number of psychiatrists, GDP,
average annual income, health care expenditures, waiting
times for consultation and nature of services. Data related
to population, number of psychiatric beds, morbidity
patterns, number of psychiatrists, GDP, average annual
income, health care expenditures, waiting times for
consultation and nature of services was gathered
systematically from literature search using PubMed, Google,
Medline and publications from the W.H.O., UNICEF, Canadian
Medical Association, Pakistan Medical and Dental Council,
Government of Newfoundland and Labrador and local monographs
for both cities in the developing and developed
countries. Two cities from different worlds in terms of
population, St. John’s, Canada with a significantly low
population and Karachi, Pakistan where majority of the
people are rural-based giving a picture of low population
vs. high population. Number of psychiatric beds is much
smaller compared to the population of Karachi, prevalence of
mental illnesses is of higher magnitude, low average annual
income, there is no established model for mental health care
and general health care expenditure is from out of pocket.
St. John’s has a full-fledged model with some community and
specialized services, which are government sponsored, but
the striking feature of this is the long waiting time
hindering the health care benefits to the local population.
Karachi with all its problems has practically zero to one
week’s waiting time despite low number of
psychiatrists. There are problems in service delivery for
mental health both in the developing and the developed world
and therefore, there is a room for improvement by mutual
learning and modification of available resources.
Full
Article
Ferguson D,
Cahill O.J,
Quilty B
Abstract
P.aeruginosa
is a significant pathogen associated with nosocomial and
community-acquired chronic infection. Presumptive
P.aeruginosa isolates were obtained from two Irish
hospitals. The aim of this study was to phenotypically and
genotypically characterise the isolates, and assess their
innate virulence in response to antibiotic treatment. The
clinical strains were characterised biochemically by API NE
and Biolog GN systems, and subsequently confirmed as
P.aeruginosa by 16s rRNA sequence analysis. Their
genetic relationship was established by Phylogenetic
analysis of the 16s rRNA, which confirmed individuality
amongst the strains but more significantly, genetic
similarity to known clinical isolates of P.aeruginosa
and Burkholderia cepacia, the cystic fibrosis
pathogen. Antibiotic resistance profiles were completed on
all the isolates to obtain MIC values for numerous
antibiotics. Extrapolation of the MIC profiles identified
one multi-resistant strain, characterised by high-level
resistance to gentamicin, the topically administered
treatment for invasive P.aeruginosa infection. This
strain was chosen for further study.
Biochemical
tests identified all the clinical isolates as
P.aeruginosa, which with the exception of subtle
metabolic differences were indistinguishable from each
other. Phenotypic differences were confirmed by 16s rRNA
sequencing which identified genetic relationship with other
clinical pathogens. MIC profiling identified one
multi-resistant clinical isolate, P.aeruginosa PA13,
resistant to all classes of antibiotic, specifically
aminoglycosides. This study
demonstrated that the
occurrence of chronic P.aeruginosa infection is not
restricted to one genotype, as confirmed by phylogenetic and
molecular epidemiology. It also illustrates the potential
for cross-resistance between clinical isolates in nosocomial
environments, confirming the need for more rigorous
infection control protocols.
Full
Article
Abstract
Active trypsin in blood
could severely modulate hemostasis. In the present study citrated blood
or plasma of
healthy donors was pre-incubated with trypsin. The plasma was
recalcified and specific thrombin generation was
measured. 1-10 ng/ml
trypsin enhances intrinsic thrombin generation > 2fold. Trypsin might
activate intrinsic coagulation factors or prothrombin (100 ng/ml trypsin
generates within 60 min 15 mIU/ml thrombin from 100 4g/ml prothrombin),
causing a pathologic disseminated intravascular coagulation. The
recalcified coagulation
activity assay (RECA)
allows to investigate the action of trypsin on intrinsic thrombin
generation. The RECA is a very sensitive method to detect prothrombotic
changes of blood.
Full Article
|
