MyMedR

Fulltext A menstrual anomaly: calendar cycling in a Malay population

Dobbins JG

Med J Malaysia, 1982 Sep;37(3):253-6.

Women in an urban, Malay population reported menstrual period lengths that tended to coincide with the lengths of the calendar months in which the periods began. This pattern may be related to the calendar-month pay periods for the population.

Matched MeSH terms: Periodicity*

Fulltext The Role of GnIH in Biological Rhythms and Social Behaviors

Teo CH, Phon B, Parhar I

Front Endocrinol (Lausanne), 2021;12:728862.

PMID: 34566893 DOI: 10.3389/fendo.2021.728862

Gonadotropin-inhibitory hormone (GnIH) was first discovered in the Japanese quail, and peptides with a C-terminal LPXRFamide sequence, the signature protein structure defining GnIH orthologs, are well conserved across vertebrate species, including fish, reptiles, amphibians, avians, and mammals. In the mammalian brain, three RFamide-related proteins (RFRP-1, RFRP-2, RFRP-3 = GnIH) have been identified as orthologs to the avian GnIH. GnIH is found primarily in the hypothalamus of all vertebrate species, while its receptors are distributed throughout the brain including the hypothalamus and the pituitary. The primary role of GnIH as an inhibitor of gonadotropin-releasing hormone (GnRH) and pituitary gonadotropin release is well conserved in mammalian and non-mammalian species. Circadian rhythmicity of GnIH, regulated by light and seasons, can influence reproductive activity, mating behavior, aggressive behavior, and feeding behavior. There is a potential link between circadian rhythms of GnIH, anxiety-like behavior, sleep, stress, and infertility. Therefore, in this review, we highlight the functions of GnIH in biological rhythms, social behaviors, and reproductive and non-reproductive activities across a variety of mammalian and non-mammalian vertebrate species.

Matched MeSH terms: Periodicity*

Fulltext The effectiveness of Dalcroze Music Approach in enhancing musical coordination skill among year 4 students in urban area

Md Jais Ismail

Malaysian Journal of Social Sciences and Humanities, 2017;2(1):54-65.

MyJurnal

This study is designed in qualitative form which focuses on musical coordination skill that is sing and
clapping rhythm simultaneously in meter . The researcher used one of music teaching method which
is Dalcroze Approach as an intervention in this study. Dalcroze Approach is a method which relates
musical concepts with movement. Research sample is among Year 4 students aged 10 years old from
different sex and race. Data have been collected through observation and interview. A comprehension
exam is conducted as a supplementary data collection. Findings show the students have achieved good
result in music coordination skill after the implementation of the Dalcroze Approach. Observation
revealed that all the students have increase their coordination skill in singing and clapping the rhythm simultaneously. Interview which is conducted on students found 60 percent of them are very confident
to do the skill as well. The result of comprehension exam shows 73 percent of students score A which
can be described as excellent. Researcher wish to have further study in developing the music
coordination skill by improving the intervention of the study.

Matched MeSH terms: Periodicity

Fractionally integrated time-varying volatility under structural break: evidence from Kuala Lumpur composite index

Chin WC, Zaidi Isa, Abu Hassan Shaari Mohd. Nor

Sains Malaysiana, 2008;37:233-237.

This article study the influences of structural break to the fractionally integrated time-varying volatility model in Malaysian stock markets from year 1996 to 2006. A fractionally integrated autoregressive conditional heteroscedastic (FIGARCH) model combines with sudden changes of volatility is develops to study the possibility of structural change in Asian financial crisis and currency crisis. Our empirical results evidence substantially reduction in long memory clustering volatility after the inclusion of sudden changes in the volatility. Finally, the estimation, diagnostic and model selection evaluations indicate that the fractionally integrated model with structural change is out-performed compared to the standard model.

Matched MeSH terms: Periodicity

Generalized variable projective synchronization of time delayed systems

Banerjee S, Theesar SJ, Kurths J

Chaos, 2013 Mar;23(1):013118.

PMID: 23556955 DOI: 10.1063/1.4791589

We study generalized variable projective synchronization between two unified time delayed systems with constant and modulated time delays. A novel Krasovskii-Lyapunov functional is constructed and a generalized sufficient condition for synchronization is derived analytically using the Lyapunov stability theory and adaptive techniques. The proposed scheme is valid for a system of n-numbers of first order delay differential equations. Finally, a new neural oscillator is considered as a numerical example to show the effectiveness of the proposed scheme.

Matched MeSH terms: Periodicity*

Fulltext Reliability and validity of the Chinese version of the biological rhythms interview of assessment in neuropsychiatry in patients with major depressive disorder

He S, Ding L, He K, Zheng B, Liu D, Zhang M, et al.

BMC Psychiatry, 2022 Dec 29;22(1):834.

PMID: 36581864 DOI: 10.1186/s12888-022-04487-w

BACKGROUND: Although disturbances in biological rhythms are closely related to the onset of major depressive disorder (MDD), they are not commonly assessed in Chinese clinical practice. The Biological Rhythms Interview of Assessment in Neuropsychiatry (BRIAN) has been used to evaluate disturbances in biological rhythms in MDD. We aimed to assess and confirm the reliability and validity of the Chinese version of the BRIAN (C-BRIAN) in patients with MDD.

METHODS: A total of 120 patients with MDD and 40 age- and sex-matched controls were recruited consecutively. Reliability was estimated using Cronbach's alpha, the split-half coefficient, and the test-retest coefficient; test-retest reliability was assessed using Spearman's correlation coefficient. A confirmatory factor analysis was used to determine the construct validity of the scale. The Pittsburgh Sleep Quality Index (PSQI) and the Morningness-Eveningness Questionnaire (MEQ) were used to check concurrent validity by evaluating the correlation between the C-BRIAN, PSQI, and MEQ.

RESULTS: The overall Cronbach's α value was 0.898, indicating good internal consistency. The Guttman split-half coefficient was 0.792, indicating good split-half reliability. Moreover, the test-retest reliability for both the total and individual item score was excellent. Confirmatory factor analysis revealed that construct validity was acceptable (χ2/df = 2.117, GFI = 0.80, AGFI = 0.87, CFI = 0.848, and RMSEA = 0.097). Furthermore, total BRIAN scores were found to be negatively correlated with MEQ (r = - 0.517, P

Matched MeSH terms: Periodicity

Biology of the Malaysian strain of Plasmodium juxtanucleare Versiani and Gomes, 1941. 3. Life cycle of the erythrocytic parasite in the avian host

Bennett GF, Warren M

J Parasitol, 1966 Aug;52(4):653-9.

PMID: 5969103

Matched MeSH terms: Periodicity

Plasmodium jefferyi sp. n. from Hylobates lar in Malaya

Warren M, Coatney GR, Skinner JC

J Parasitol, 1966 Feb;52(1):9-13.

PMID: 5910463

Matched MeSH terms: Periodicity

Studies on filariasis in New Guinea. Observations on periodicity

Saave JJ, Desowitz RS

Med J Malaya, 1966 Jun;20(4):335-6.

PMID: 4224350

Matched MeSH terms: Periodicity

The periodicity of the microfilariae of Brugia malayi in Cheju Island, Korea

Seo BS

Kisaengchunghak Chapchi, 1974 Dec;12(2):95-100.

PMID: 12913470

The periodicity of the microfilariae of Brugia malayi was studied in 9 human carriers from Shin-san Ri, Seong-san Myon, Cheju Island. The periodicity pattern was markedly nocturnal and the peaks were observed between 21:30 p.m. and 5:30 a.m. The average peak count was 1:30 a.m. and the percentage of peak count at this time was 95.3. The ratio of minimum of the average peak count percentage to the maximum was 8.3. The periodicity pattern of B.malayi in Cheju Island was compared with that in Inland and no differences were found between two forms. From the above observations, it was concluded that the periodicity of B. malayi in Korea is markedly nocturnal and closely resembles that in the strain of Penang, Malaya.

Matched MeSH terms: Periodicity

Studies on the Malayan forest rat filaria, Breinlia booliati: periodicity and microfilaraemic patterns during the course of infection

Yap EH, Ho BC, Singh M, Kang KL, Lim BL

J Helminthol, 1975 Dec;49(4):263-9.

PMID: 1206216

Breinlia booliati exhibited nocturnal subperiodicity in its natural host, Rattus sabanus in contrast to experimentally infected laboratory-reared albine rats which showed irregular fluctuations of microfilariae throughout the 24 hour cycle. All the infected albino rats showed a prepatent period between 11-14 weeks postinoculation. Three patterns of microfilaraemia were discerned during the course of infection 38/49 rats displayed a single peak, 4/49 displayed 2 peaks about 12-15 weeks apart and 7/49 showed a sustained high plateau-like pattern of microfilaraemia. Cortisone had no effect on microfilarial levels when administered to rats near postpatency and some at postpatency.

Matched MeSH terms: Periodicity*

Ultra-slow oscillations in cortical networks in vitro

Mok SY, Nadasdy Z, Lim YM, Goh SY

Neuroscience, 2012 Mar 29;206:17-24.

PMID: 22266346 DOI: 10.1016/j.neuroscience.2012.01.009

An ultra-slow oscillation (<0.01 Hz) in the network-wide activity of dissociated cortical networks is described in this article. This slow rhythm is characterized by the recurrence of clusters of large synchronized bursts of activity lasting approximately 1-3 min, separated by an almost equivalent interval of relatively smaller bursts. Such rhythmic activity was detected in cultures starting from the fourth week in vitro. Our analysis revealed that the propagation motifs of constituent bursts were strongly conserved across multiple oscillation cycles, and these motifs were more consistent at the electrode level compared with the neuronal level.

Matched MeSH terms: Periodicity

Fulltext Anopheles donaldi incriminated as a vector of periodic Brugia malayi in Grik, Perak, Malaysia

Vythilingam I, Hakim SL, Chan ST, Mak JW

Southeast Asian J. Trop. Med. Public Health, 1996 Sep;27(3):637-41.

PMID: 9185284

Studies were carried out to observe the species composition of mosquitos and to determine the vectors responsible for the transmission of filariasis in Grik, Perak, Malaysia. A total of 2,155 mosquitos belonging to 7 genera and 30 species were collected. Anopheles donaldi comprised 24.1% of the collection. Twelve out of 519 An. donaldi were infected with L3 larvae of Brugia malayi. The peak biting time was around 23.00-24.00 hours. The infective bites per month ranged from 0 to 6.3.

Matched MeSH terms: Periodicity

Comparative studies of firefly pacemakers

Hanson FE

Fed. Proc., 1978 Jun;37(8):2158-64.

PMID: 658456

Rhythmic flashing behavior of synchronous flashing fireflies from Malaysia and New Guinea was studied. The "circa second" firefly pacemaker has characteristics analogous to circadian rhythms, such as entrainment, phase shifting, limits of entrainment, fringe entrainment, and effects of the light:dark ratio on phase. The three species studied show different phase-response curves; a light pulse causes a large phase shift in one firefly species (Pteroptyx cribellata) but small phase shifts in others (Pteroptyx malaccae and Luciola pupilla). Comparative studies of the phase angle differences between the animal's flash and the flash of a controlled light source suggest at least two different mechanisms of attaining synchrony: 1) by cycle-to-cycle phase shifting of a stable oscillator; 2) by changing the underlying period (tau) of a variable oscillator.

Matched MeSH terms: Periodicity

Chemotherapeutic effect of CGI 18041 against subperiodic Brugia malayi infection in Presbytis cristata

Mak JW, Ngah Z, Choong MF, Navaratnam V

Trop. Med. Parasitol., 1995 Mar;46(1):6-8.

PMID: 7631131

CGI 18041, an adduct of benzothiazol isothiocyanate N-methyl piperazine, was evaluated for its antifilarial properties in subperiodic Brugia malayi infected Presbytis cristata. Animals experimentally infected with 200-400 subperiodic Brugia malayi infective larvae, were matched according to microfilaria density, infective dose, and duration of infection. They were then randomly assigned to various treatment and control groups. The compound was suspended in 1% Tween 20 in distilled water, sonicated, and then fed to monkeys using a stomach tube. Control animals received an equivalent volume of drug diluent. CGI 18041 at a single oral dose of 50 mg/kg had complete adulticidal and microfilaricidal activities against subperiodic B. malayi in P. cristata. It was also extremely effective at a single dose of 25 mg/kg, the final geometric mean microfilaria count being 1.6% of initial level, and only 1.0% of the infective dose was recovered as live adult worms at autopsy 6 weeks post-treatment. In control animals, these were 226.9% and 5.56% respectively.

Matched MeSH terms: Periodicity

Fulltext A report of Anopheles (Diptera: Culicidae) attracted to cow bait in a malaria endemic village in Peninsular Malaysia near the Thailand border

Rahman WA, Abu Hassan A, Adanan CR, Mohd Razha R

Southeast Asian J. Trop. Med. Public Health, 1995 Jun;26(2):359-63.

PMID: 8629076

Twelve species of Anopheles were collected by using cow-baited net trap in a malarial endemic village in northern Peninsular Malaysia. Anopheles maculatus which is the main malaria vector with its densities were related to drought. An. aconitus, An. kochi and An. philippinensis were less susceptible to P. falciparum and P. vivax infection, and are not considered important in falciparum or vivax malaria transmission. Biting activities of An. kochi and An. vagus were primarily active after dusk and steadily declined after midnight. An. maculatus and An. aconitus showed biting activities throughout the night but An. maculatus showed two peaks of biting activity in the first half of the night.

Matched MeSH terms: Periodicity

Parasitological and entomological studies on filariasis in seven villages, Serian District, Sarawak, East Malaysia

Rubis P, Chang MS, Nagum AJ, Jau JL

Southeast Asian J. Trop. Med. Public Health, 1981 Mar;12(1):30-5.

PMID: 6114566

A total of 82 persons have been found to be positive for microfilaria a sub-periodic Brugia malayi out of 1,613 examined in seven villages in Serian District. This represents an average microfilaria infection rate of 5.1% with a range of zero to 10.7%. It is found that males are more predominantly affected than females with a ratio of 3:1. It is also confirmed that Mansonia dives and M. bonneae are possible vectors for the transmission of the disease although Anopheles species cannot be ruled out owing to the small number of specimens examined. The study is confined to areas where indoor DDT spraying has been done since 1960 and only in two of the areas it has been terminated in 1966. Yet to be published data shows higher filaria infection rate than any of these villages.

Matched MeSH terms: Periodicity

Fulltext Hematological changes in subperiodic Brugia malayi infection of the leaf-monkey, Presbytis cristata

Choong MF, Mak JW

Southeast Asian J. Trop. Med. Public Health, 1991 Jun;22(2):168-70.

PMID: 1948274

Hematological changes were monitored in the leaf-monkey, Presbytis cristata, infected experimentally with 200 subperiodic Brugia malayi infective larvae. Prepatent periods were 54-86 days and peak microfilarial geometric mean counts (GMCs) were 1324 per ml blood. Total leukocyte and differential counts were measured at pre-infection, and then at weakly intervals before and during patency. Blood eosinophil level increased to about thrice the initial level at 3 weeks post-infection and this was maintained for the next 13 weeks before it started to rise again, increasing to more than 5 times the initial level at 20 weeks post-infection. The observed pattern of eosinophilia is probably related to the level of microfilaremia and the destruction of microfilariae in the spleen. There was no significant change in the total leukocyte counts during the period of observation.

Matched MeSH terms: Periodicity

Experimental infection of Rattus sabanus and Rattus muelleri with subperiodic Brugia malayi

Sivanandam S, Mak JW, Lai PF

Southeast Asian J. Trop. Med. Public Health, 1975 Mar;6(1):68-73.

PMID: 1145240

R. sabanus and R. muelleri are very common in the lowland forests of Malaysia. In nature they are infected with Breinlia sp. and D. ramachandrani. In an attempt to determine whether they are also susceptible to subperiodic B. malayi and thereby being potential reservoirs of infection of the disease, 24 R. muelleri and 17 R. sabanus were experimentally infected with the parasite. Results show that although they can support the full development of the parasite, they are poor hosts. This confirms the observation that in Malaysia natural infection of Rattus spp. with the parasite has not been seen. These rats therefore are probably not important in the zoonotic transmission of subperiodic B. malayi in Malaysia.

Matched MeSH terms: Periodicity

Plasmodium inui is not closely related to other quartan Plasmodium species

Kissinger JC, Collins WE, Li J, McCutchan TF

J Parasitol, 1998 Apr;84(2):278-82.

PMID: 9576499

Plasmodium inui (Halberstaedter and von Prowazek, 1907), a malarial parasite of Old World monkeys that occurs in isolated pockets throughout the Celebes, Indonesia, Malaysia, and the Philippines, has traditionally been considered to be related more closely to Plasmodium malariae of humans (and its primate counterpart Plasmodium brasilianum), than to other primate Plasmodium species. This inference was made in part because of the similarities in the periodicities or duration of the asexual cycle in the blood, the extended sporogonic cycle, and the longer period of time for development of the pre-erythrocytic stages in the liver. Both P. inui and P. malariae have quartan (72 hr) periodicities associated with their asexual cycle, whereas other primate malarias, such as Plasmodium fragile and Plasmodium cynomolgi, are associated with tertian periodicities (48 hr), and Plasmodiumn knowlesi, with a quotidian (24 hr) periodicity. Phylogenetic analyses of portions of orthologous small subunit ribosomal genes reveal that P. inui is actually more closely related to the Plasmodium species of the "vivax-type" lineage than to P. malariae. Ribosomal sequence analysis of many different, geographically isolated, antigenically distinct P. inui isolates reveals that the isolates are nearly identical in sequence and thus members of the same species.

Matched MeSH terms: Periodicity

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