Morphology and Anatomy of Leaf, Stem and Petiole of Luvunga crassifolia Tanaka (Rutaceae)

Luvunga crassifolia is an underutilized plant in the Citrus family. Other than brief morphological descriptions, there are no published reports on other identification features of this plant. Thus, the current study was aimed to investigate macroscopic and microscopic diagnostic features of L. crassifolia leaves, stems, and petioles. Macroscopic characterization, optimization of histological procedure, and histochemical analyses of differential stains were carried out on the leaves, stems, and petioles of L. crassifolia. The histological method was optimized by modifying the following parameters: number of fixation days, dehydration duration with degraded series of ethanol or butanol, clearing duration, and infiltration duration. After infiltration, embedding and sectioning of the tissues were performed. Histochemical analyses were carried out using differential stains to identify the cellular components in leaf, stem and, petiole tissue sections. This study showed that L. crassifolia leaves are amphistomatic. Pellucid dots were observed on both adaxial and abaxial leaf surfaces. Secretory cavities, xylem, phloem, and pericyclic fibers were found in the cross-sections of leaf, stem, and petiole. Calcium oxalates were present in the leaf and stem sections, while trichomes were detected in stem and petiole sections. The information obtained from this study will be helpful for the identification and future taxonomic-related studies of this plant species.

Aggregation of hepatic melanomacrophage centers in S. herzbergii (Pisces, Ariidae) as indicators of environmental change and well-being

ABSTRACT The melanomacrophage centers (MMCs) in the liver of fish are indicators of environmental conditions, as they are involved in xenobiotic biotransformation. The objective of this study was to evaluate the number of MMC in the liver of juveniles and adults of Sciades herzbergii from areas with different levels of contamination. The fish were caught at three points (reference - A1, potentially impacted - A2 and contaminated - A3), in São José bay (Maranhão, Brazil), in four samples. The livers were subjected to the standard histological procedure and 5μm sections were stained with hematoxylin-eosin. In livers of A2 adult individuals (260.50±161.50 MMCs / mm²) they presented a greater number of MMCs when compared to A3 adults (60.00 ± 30.10 MMCs / mm²). Juveniles showed considerable values in A1 (100.00 ± 0.00 MMCs/mm²) and A2 (95.33 ± 33.00 MMCs / mm²) compared to juveniles in A3 (49.00±0.00 MMCs/mm²). These high values are unexpected for young people. The average number of MMC correlated with the rainy season in the region. The use of hepatic MMCs as a biomarker of exposure to pollutants, in particular substances from fisheries systems, such as ammonia and nitrite, proved to be adequate to differentiate areas with different levels of impacts.

​The Histopathology of Alimentary Canal of Stinging Catfish Heteropneustes fossilis (Bloch, 1794), Susceptible for Trematodes Incursion

Background: Heteropneustes fossilis (Bloch, 1794) is one of the popular freshwater fish known for its food quality and nutritional value. This study was undertaken with an aim to find out histopathological changes in the intestine of freshwater fish Heteropneustes fossilis, host of trematode parasite Masenia vittatusia Agarwal, 1963. Methods: The intestine of uninfected fish used to determine normal anatomy, while infected intestine to determine pathological changes. The normal histological procedure was followed, which included fixing, rinsing, dehydrating and embedding of tissue. Tissue was cut in 4-6 µm thick sections using a rotary microtome. Haematoxylin and eosin stains were used. Result: The highest damage was observed in the mucosal layer with ruptured and fused microvilli, hyperplasia of villi, damaged columnar epithelium layer and spread of loose connective tissue into the lumen. Other degenerative modifications included hypertrophy of blood vessels in mucosa and muscularis part, some of them ruptured might be the cause of haemorrhage inside the layers. Other changes include variation in the routine shape of all three layers. The mucosal layer showed aggregation of lymphocytes and mast cells as well.

Adaptation of the Relationship in the "Parasite–Host" System with Parasitism Paramphistomum сervi in the Small Intestine of Sheeps

The purpose of the research is studying microstructural changes in the process of adaptation of components during the formation of the “parasite–host” system by the example of Paramphistomum cervi (Zeder, 1790) parasitizing in the small intestine of spontaneously infected sheep. Materials and methods. Peculiarities of changes in the microstructure of the small intestine in the “parasite–host” system were studied using parasitization of P. cervi in the intestines of sheep using well-known histological methods. Pieces of tissue of the small intestine of sheep with P. cervi, after being preserved in 70% alcohol, were processed according to the generally accepted histological procedure and embedded in paraffin. Sections 5–7 μm in thickness were stained with histological stains and examined under a light microscope. Results and discussion. Microstructural analysis of the characteristics of the relationship in the "parasite–host" system showed that the mucous membrane of the small intestine of sheep in the presence of P. cervi looks sharply thickened. Swelling of the epithelium of villi and crypts, its vacuolization and albuminoid degeneration were found. In some places, proliferation of the epithelial layer of the mucous membrane was detected, due to which epithelial hyperplasia is observed, in some cases turning into metaplasia. Proliferation and hyperplasia (metaplasia) in the endostation of the host in the presence of the parasite contribute to: 1. stability of the parasite-host system and the participation of trematodes in trophism; 2. determination of the clinical and morphological picture of trematodose; 3. predicting the effects of this pathology on the host. Adhesion in the microstructural complex “trematode tegument – epithelial tissue of the villi of the small intestine” in ovine paramphistomosis at the contact level of two glycocalyx layers – the tegument of P. cervi and the surface of the epithelial cells of the villi of the host’s intestine, as well as single histological staining of the sites of contact between the parasite and the host as a result of mixing the components of the trematode tegument and the tissue of the host’s small intestine with deep adhesion indicate the established mutual relations between the components of a single system "parasite–host".

Biología reproductiva y contenido bioquímico gonadal de la cabrilla arenera, Paralabrax maculatofasciatus en la región de Bahía de Kino, Sonora//Reproductive biology and biochemical gonadal content of the spotted sand bass, Paralabrax maculatofasciatus in Kino Bay, Sonora

A pesar de la importancia económica que representa la cabrilla arenera, Paralabrax maculatofasciatus, la información acerca de sus aspectos reproductivos es escasa, por lo que se investigó su biología reproductiva así como su composición proximal de la gónada. Para ello, se capturaron 30 organismos mensualmente de marzo 2017 a febrero 2018. Los peces se midieron, pesaron y disectaron para obtener el factor de condición (K), el índice hepatosomático (IHS) y el índice gonadosomático (IGS). Adicionalmente, se preservó tejido de gónada para llevar a cabo el proceso histológico y la tinción hematoxilina-eosina. Los resultados indicaron que el IHS y el IGS fueron afectados significativamente (P<0.05). El análisis histológico evidenció la presencia de machos maduros en abril, así como de octubre a noviembre, y para las hembras, se observó la presencia de organismos desarrollados en abril y de octubre a diciembre. Adicionalmente, se detectó la presencia de organismos en transición de hembra a macho. El análisis proximal mostró el valor máximo de grasa en abril, lo cual coincidió con el menor valor de humedad. El análisis de proporción mostró una significativa dominancia de machos. Los datos obtenidos en la presente investigación coadyuvarán en la implementación de programas de protección para la especie.ABSTRACTDespite the economic importance of sand bass, Paralabrax maculatofasciatus, little information regarding its reproductive aspects is known. In this study, gonadal maturity stage, biological indexes, proximate gonad composition and sex ratio proportion were determined. A total of 30 wild spotted sand bass were monthly obtained from March 2017 to February 2018. Organisms were measured, weighted and dissected in order to obtain the condition factor (K), hepatosomatic index (IHS) and gonadosomatic index (IGS). A small portion of gonad was preserved to perform the histological procedure, and stained with Harris´ hematoxilineosin technique. The results indicate that somatic indexes were significantly affected (P<0.05) in terms of IHS and IGS. Histological analysis showed the presence of ripe males in April and from October to November, and for females, the presence of developed organisms was observed in April and from October to December. Additionally, the presence of transitional organisms from female to male was observed. The proximate analysis showed the maximum crude fat value in April, which coincides with the lowest moisture value. Sex proportion showed a significant male dominance. These data provide valuable information for the development of protection programs to encourage a sustainable fishery of the species.

Observational Study on the Occurrence of Muscle Spindles in Human Digastric and Mylohyoideus Muscles

Although the occurrence of muscle spindles (MS) is quite high in most skeletal muscles of humans, few MS, or even absence, have been reported in digastric and mylohyoideus muscles. Even if this condition is generally accepted and quoted in many papers and books, observational studies are scarce and based on histological sections of a low number of specimens. The aim of the present study is to confirm previous data, assessing MS number in a sample of digastric and mylohyoideus muscles. We investigated 11 digastric and 6 mylohyoideus muscles from 13 donors. Muscle samples were embedded in paraffin wax, cross-sectioned in a rostrocaudal direction, and stained using haematoxylin-eosin. A mean of 5.1 ± 1.1 (range 3–7) MS was found in digastric muscles and mean of 0.5 ± 0.8 (range 0–2) in mylohyoideus muscles. A significant difference (P<0.001) was found with the control sample, confirming the correctness of the histological procedure. Our results support general belief that the absolute number of spindles is sparse in digastric and mylohyoideus muscles. External forces, such as food resistance during chewing or gravity, do not counteract jaw-opening muscles. It is conceivable that this condition gives them a limited proprioceptive importance and a reduced need for having specific receptors as MS.

Corynosoma cetaceum Johnston & Best, 1942 (Acanthocephala, Polymorphidae) in Arctocephalus australis Zimmermann, 1783 (Mammalia: Pinnipedia): Histopathology, parasitological indices, seasonality and host gender influences

The parasitological indices [Prevalence (P%), Mean Intensity (MI), Mean Abundance (MA) and the Range of Variation (Ax)] of Corynosoma cetaceum in Arctocephalus australis and the histopathology caused by this parasite are presented based on the necropsy of 32 specimens found stranded dead on the shore of Rio Grande do Sul, Brazil, from 2008 to 2010. Differences between the genders of the hosts as well as for their reproductive status [males (pups, prepubertals) and females (pups, reproductive-breeding)] were analyzed for P% (Chi-square test, X2) and MI (Bootstrap Confidence Interval, BCa , p < 0,05) and between genders of the hosts for season groups (Spring-Summer: S-S; Autumn-Winter: A-W). Abnormal tissue samplings of the stomachs (histopathology caused by the parasite) and the gonads (for analysis of the sexual maturity) of the hosts were submitted to the histological procedure of paraffin embedding and mounting of permanent slides in balsam. The infection occurred along the sampling period with low P%, MI and MA (respectively) for the genders of the hosts (males: 37.5, 2.83 and 1.5; females: 31.3, 3 and 1), for the reproductive status of the hosts (males pups: 25, 1.33 and 1; prepubertal males: 75, 4.33 and 5; female pups: 28.6, 2.5 and 1; reproductive-breeding females: 50. 5 and 5) and for season groups (S-S: 16.7, 4 and 0.67; A-W: 45, 2.78 and 1.25). Concerning to the hosts, there were no parasitological indices-related differences between genders and sexual maturation status. There were no season-related differences for P% and MI. The results suggest an accidental infection of C. cetaceum in A. australis despite the absence of severe inflammatory processes added with the parasite’s inadequate development.